drivers/char/ipmi/ipmi_msghandler.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * ipmi_msghandler.c
   4  *
   5  * Incoming and outgoing message routing for an IPMI interface.
   6  *
   7  * Author: MontaVista Software, Inc.
   8  *         Corey Minyard <minyard@mvista.com>
   9  *         source@mvista.com
  10  *
  11  * Copyright 2002 MontaVista Software Inc.
  12  */
  13
  14 #define pr_fmt(fmt) "%s" fmt, "IPMI message handler: "
  15 #define dev_fmt pr_fmt
  16
  17 #include <linux/module.h>
  18 #include <linux/errno.h>
  19 #include <linux/poll.h>
  20 #include <linux/sched.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/spinlock.h>
  23 #include <linux/mutex.h>
  24 #include <linux/slab.h>
  25 #include <linux/ipmi.h>
  26 #include <linux/ipmi_smi.h>
  27 #include <linux/notifier.h>
  28 #include <linux/init.h>
  29 #include <linux/proc_fs.h>
  30 #include <linux/rcupdate.h>
  31 #include <linux/interrupt.h>
  32 #include <linux/moduleparam.h>
  33 #include <linux/workqueue.h>
  34 #include <linux/uuid.h>
  35 #include <linux/nospec.h>
  36
  37 #define IPMI_DRIVER_VERSION "39.2"
  38
  39 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
  40 static int ipmi_init_msghandler(void);
  41 static void smi_recv_tasklet(unsigned long);
  42 static void handle_new_recv_msgs(struct ipmi_smi *intf);
  43 static void need_waiter(struct ipmi_smi *intf);
  44 static int handle_one_recv_msg(struct ipmi_smi *intf,
  45                                struct ipmi_smi_msg *msg);
  46
  47 #ifdef DEBUG
  48 static void ipmi_debug_msg(const char *title, unsigned char *data,
  49                            unsigned int len)
  50 {
  51         int i, pos;
  52         char buf[100];
  53
  54         pos = snprintf(buf, sizeof(buf), "%s: ", title);
  55         for (i = 0; i < len; i++)
  56                 pos += snprintf(buf + pos, sizeof(buf) - pos,
  57                                 " %2.2x", data[i]);
  58         pr_debug("%s\n", buf);
  59 }
  60 #else
  61 static void ipmi_debug_msg(const char *title, unsigned char *data,
  62                            unsigned int len)
  63 { }
  64 #endif
  65
  66 static bool initialized;
  67 static bool drvregistered;
  68
  69 enum ipmi_panic_event_op {
  70         IPMI_SEND_PANIC_EVENT_NONE,
  71         IPMI_SEND_PANIC_EVENT,
  72         IPMI_SEND_PANIC_EVENT_STRING
  73 };
  74 #ifdef CONFIG_IPMI_PANIC_STRING
  75 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_STRING
  76 #elif defined(CONFIG_IPMI_PANIC_EVENT)
  77 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT
  78 #else
  79 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_NONE
  80 #endif
  81 static enum ipmi_panic_event_op ipmi_send_panic_event = IPMI_PANIC_DEFAULT;
  82
  83 static int panic_op_write_handler(const char *val,
  84                                   const struct kernel_param *kp)
  85 {
  86         char valcp[16];
  87         char *s;
  88
  89         strncpy(valcp, val, 15);
  90         valcp[15] = '\0';
  91
  92         s = strstrip(valcp);
  93
  94         if (strcmp(s, "none") == 0)
  95                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_NONE;
  96         else if (strcmp(s, "event") == 0)
  97                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT;
  98         else if (strcmp(s, "string") == 0)
  99                 ipmi_send_panic_event = IPMI_SEND_PANIC_EVENT_STRING;
 100         else
 101                 return -EINVAL;
 102
 103         return 0;
 104 }
 105
 106 static int panic_op_read_handler(char *buffer, const struct kernel_param *kp)
 107 {
 108         switch (ipmi_send_panic_event) {
 109         case IPMI_SEND_PANIC_EVENT_NONE:
 110                 strcpy(buffer, "none");
 111                 break;
 112
 113         case IPMI_SEND_PANIC_EVENT:
 114                 strcpy(buffer, "event");
 115                 break;
 116
 117         case IPMI_SEND_PANIC_EVENT_STRING:
 118                 strcpy(buffer, "string");
 119                 break;
 120
 121         default:
 122                 strcpy(buffer, "???");
 123                 break;
 124         }
 125
 126         return strlen(buffer);
 127 }
 128
 129 static const struct kernel_param_ops panic_op_ops = {
 130         .set = panic_op_write_handler,
 131         .get = panic_op_read_handler
 132 };
 133 module_param_cb(panic_op, &panic_op_ops, NULL, 0600);
 134 MODULE_PARM_DESC(panic_op, "Sets if the IPMI driver will attempt to store panic information in the event log in the event of a panic.  Set to 'none' for no, 'event' for a single event, or 'string' for a generic event and the panic string in IPMI OEM events.");
 135
 136
 137 #define MAX_EVENTS_IN_QUEUE     25
 138
 139 /* Remain in auto-maintenance mode for this amount of time (in ms). */
 140 static unsigned long maintenance_mode_timeout_ms = 30000;
 141 module_param(maintenance_mode_timeout_ms, ulong, 0644);
 142 MODULE_PARM_DESC(maintenance_mode_timeout_ms,
 143                  "The time (milliseconds) after the last maintenance message that the connection stays in maintenance mode.");
 144
 145 /*
 146  * Don't let a message sit in a queue forever, always time it with at lest
 147  * the max message timer.  This is in milliseconds.
 148  */
 149 #define MAX_MSG_TIMEOUT         60000
 150
 151 /*
 152  * Timeout times below are in milliseconds, and are done off a 1
 153  * second timer.  So setting the value to 1000 would mean anything
 154  * between 0 and 1000ms.  So really the only reasonable minimum
 155  * setting it 2000ms, which is between 1 and 2 seconds.
 156  */
 157
 158 /* The default timeout for message retries. */
 159 static unsigned long default_retry_ms = 2000;
 160 module_param(default_retry_ms, ulong, 0644);
 161 MODULE_PARM_DESC(default_retry_ms,
 162                  "The time (milliseconds) between retry sends");
 163
 164 /* The default timeout for maintenance mode message retries. */
 165 static unsigned long default_maintenance_retry_ms = 3000;
 166 module_param(default_maintenance_retry_ms, ulong, 0644);
 167 MODULE_PARM_DESC(default_maintenance_retry_ms,
 168                  "The time (milliseconds) between retry sends in maintenance mode");
 169
 170 /* The default maximum number of retries */
 171 static unsigned int default_max_retries = 4;
 172 module_param(default_max_retries, uint, 0644);
 173 MODULE_PARM_DESC(default_max_retries,
 174                  "The time (milliseconds) between retry sends in maintenance mode");
 175
 176 /* Call every ~1000 ms. */
 177 #define IPMI_TIMEOUT_TIME       1000
 178
 179 /* How many jiffies does it take to get to the timeout time. */
 180 #define IPMI_TIMEOUT_JIFFIES    ((IPMI_TIMEOUT_TIME * HZ) / 1000)
 181
 182 /*
 183  * Request events from the queue every second (this is the number of
 184  * IPMI_TIMEOUT_TIMES between event requests).  Hopefully, in the
 185  * future, IPMI will add a way to know immediately if an event is in
 186  * the queue and this silliness can go away.
 187  */
 188 #define IPMI_REQUEST_EV_TIME    (1000 / (IPMI_TIMEOUT_TIME))
 189
 190 /* How long should we cache dynamic device IDs? */
 191 #define IPMI_DYN_DEV_ID_EXPIRY  (10 * HZ)
 192
 193 /*
 194  * The main "user" data structure.
 195  */
 196 struct ipmi_user {
 197         struct list_head link;
 198
 199         /*
 200          * Set to NULL when the user is destroyed, a pointer to myself
 201          * so srcu_dereference can be used on it.
 202          */
 203         struct ipmi_user *self;
 204         struct srcu_struct release_barrier;
 205
 206         struct kref refcount;
 207
 208         /* The upper layer that handles receive messages. */
 209         const struct ipmi_user_hndl *handler;
 210         void             *handler_data;
 211
 212         /* The interface this user is bound to. */
 213         struct ipmi_smi *intf;
 214
 215         /* Does this interface receive IPMI events? */
 216         bool gets_events;
 217 };
 218
 219 static struct ipmi_user *acquire_ipmi_user(struct ipmi_user *user, int *index)
 220         __acquires(user->release_barrier)
 221 {
 222         struct ipmi_user *ruser;
 223
 224         *index = srcu_read_lock(&user->release_barrier);
 225         ruser = srcu_dereference(user->self, &user->release_barrier);
 226         if (!ruser)
 227                 srcu_read_unlock(&user->release_barrier, *index);
 228         return ruser;
 229 }
 230
 231 static void release_ipmi_user(struct ipmi_user *user, int index)
 232 {
 233         srcu_read_unlock(&user->release_barrier, index);
 234 }
 235
 236 struct cmd_rcvr {
 237         struct list_head link;
 238
 239         struct ipmi_user *user;
 240         unsigned char netfn;
 241         unsigned char cmd;
 242         unsigned int  chans;
 243
 244         /*
 245          * This is used to form a linked lised during mass deletion.
 246          * Since this is in an RCU list, we cannot use the link above
 247          * or change any data until the RCU period completes.  So we
 248          * use this next variable during mass deletion so we can have
 249          * a list and don't have to wait and restart the search on
 250          * every individual deletion of a command.
 251          */
 252         struct cmd_rcvr *next;
 253 };
 254
 255 struct seq_table {
 256         unsigned int         inuse : 1;
 257         unsigned int         broadcast : 1;
 258
 259         unsigned long        timeout;
 260         unsigned long        orig_timeout;
 261         unsigned int         retries_left;
 262
 263         /*
 264          * To verify on an incoming send message response that this is
 265          * the message that the response is for, we keep a sequence id
 266          * and increment it every time we send a message.
 267          */
 268         long                 seqid;
 269
 270         /*
 271          * This is held so we can properly respond to the message on a
 272          * timeout, and it is used to hold the temporary data for
 273          * retransmission, too.
 274          */
 275         struct ipmi_recv_msg *recv_msg;
 276 };
 277
 278 /*
 279  * Store the information in a msgid (long) to allow us to find a
 280  * sequence table entry from the msgid.
 281  */
 282 #define STORE_SEQ_IN_MSGID(seq, seqid) \
 283         ((((seq) & 0x3f) << 26) | ((seqid) & 0x3ffffff))
 284
 285 #define GET_SEQ_FROM_MSGID(msgid, seq, seqid) \
 286         do {                                                            \
 287                 seq = (((msgid) >> 26) & 0x3f);                         \
 288                 seqid = ((msgid) & 0x3ffffff);                          \
 289         } while (0)
 290
 291 #define NEXT_SEQID(seqid) (((seqid) + 1) & 0x3ffffff)
 292
 293 #define IPMI_MAX_CHANNELS       16
 294 struct ipmi_channel {
 295         unsigned char medium;
 296         unsigned char protocol;
 297 };
 298
 299 struct ipmi_channel_set {
 300         struct ipmi_channel c[IPMI_MAX_CHANNELS];
 301 };
 302
 303 struct ipmi_my_addrinfo {
 304         /*
 305          * My slave address.  This is initialized to IPMI_BMC_SLAVE_ADDR,
 306          * but may be changed by the user.
 307          */
 308         unsigned char address;
 309
 310         /*
 311          * My LUN.  This should generally stay the SMS LUN, but just in
 312          * case...
 313          */
 314         unsigned char lun;
 315 };
 316
 317 /*
 318  * Note that the product id, manufacturer id, guid, and device id are
 319  * immutable in this structure, so dyn_mutex is not required for
 320  * accessing those.  If those change on a BMC, a new BMC is allocated.
 321  */
 322 struct bmc_device {
 323         struct platform_device pdev;
 324         struct list_head       intfs; /* Interfaces on this BMC. */
 325         struct ipmi_device_id  id;
 326         struct ipmi_device_id  fetch_id;
 327         int                    dyn_id_set;
 328         unsigned long          dyn_id_expiry;
 329         struct mutex           dyn_mutex; /* Protects id, intfs, & dyn* */
 330         guid_t                 guid;
 331         guid_t                 fetch_guid;
 332         int                    dyn_guid_set;
 333         struct kref            usecount;
 334         struct work_struct     remove_work;
 335 };
 336 #define to_bmc_device(x) container_of((x), struct bmc_device, pdev.dev)
 337
 338 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
 339                              struct ipmi_device_id *id,
 340                              bool *guid_set, guid_t *guid);
 341
 342 /*
 343  * Various statistics for IPMI, these index stats[] in the ipmi_smi
 344  * structure.
 345  */
 346 enum ipmi_stat_indexes {
 347         /* Commands we got from the user that were invalid. */
 348         IPMI_STAT_sent_invalid_commands = 0,
 349
 350         /* Commands we sent to the MC. */
 351         IPMI_STAT_sent_local_commands,
 352
 353         /* Responses from the MC that were delivered to a user. */
 354         IPMI_STAT_handled_local_responses,
 355
 356         /* Responses from the MC that were not delivered to a user. */
 357         IPMI_STAT_unhandled_local_responses,
 358
 359         /* Commands we sent out to the IPMB bus. */
 360         IPMI_STAT_sent_ipmb_commands,
 361
 362         /* Commands sent on the IPMB that had errors on the SEND CMD */
 363         IPMI_STAT_sent_ipmb_command_errs,
 364
 365         /* Each retransmit increments this count. */
 366         IPMI_STAT_retransmitted_ipmb_commands,
 367
 368         /*
 369          * When a message times out (runs out of retransmits) this is
 370          * incremented.
 371          */
 372         IPMI_STAT_timed_out_ipmb_commands,
 373
 374         /*
 375          * This is like above, but for broadcasts.  Broadcasts are
 376          * *not* included in the above count (they are expected to
 377          * time out).
 378          */
 379         IPMI_STAT_timed_out_ipmb_broadcasts,
 380
 381         /* Responses I have sent to the IPMB bus. */
 382         IPMI_STAT_sent_ipmb_responses,
 383
 384         /* The response was delivered to the user. */
 385         IPMI_STAT_handled_ipmb_responses,
 386
 387         /* The response had invalid data in it. */
 388         IPMI_STAT_invalid_ipmb_responses,
 389
 390         /* The response didn't have anyone waiting for it. */
 391         IPMI_STAT_unhandled_ipmb_responses,
 392
 393         /* Commands we sent out to the IPMB bus. */
 394         IPMI_STAT_sent_lan_commands,
 395
 396         /* Commands sent on the IPMB that had errors on the SEND CMD */
 397         IPMI_STAT_sent_lan_command_errs,
 398
 399         /* Each retransmit increments this count. */
 400         IPMI_STAT_retransmitted_lan_commands,
 401
 402         /*
 403          * When a message times out (runs out of retransmits) this is
 404          * incremented.
 405          */
 406         IPMI_STAT_timed_out_lan_commands,
 407
 408         /* Responses I have sent to the IPMB bus. */
 409         IPMI_STAT_sent_lan_responses,
 410
 411         /* The response was delivered to the user. */
 412         IPMI_STAT_handled_lan_responses,
 413
 414         /* The response had invalid data in it. */
 415         IPMI_STAT_invalid_lan_responses,
 416
 417         /* The response didn't have anyone waiting for it. */
 418         IPMI_STAT_unhandled_lan_responses,
 419
 420         /* The command was delivered to the user. */
 421         IPMI_STAT_handled_commands,
 422
 423         /* The command had invalid data in it. */
 424         IPMI_STAT_invalid_commands,
 425
 426         /* The command didn't have anyone waiting for it. */
 427         IPMI_STAT_unhandled_commands,
 428
 429         /* Invalid data in an event. */
 430         IPMI_STAT_invalid_events,
 431
 432         /* Events that were received with the proper format. */
 433         IPMI_STAT_events,
 434
 435         /* Retransmissions on IPMB that failed. */
 436         IPMI_STAT_dropped_rexmit_ipmb_commands,
 437
 438         /* Retransmissions on LAN that failed. */
 439         IPMI_STAT_dropped_rexmit_lan_commands,
 440
 441         /* This *must* remain last, add new values above this. */
 442         IPMI_NUM_STATS
 443 };
 444
 445
 446 #define IPMI_IPMB_NUM_SEQ       64
 447 struct ipmi_smi {
 448         /* What interface number are we? */
 449         int intf_num;
 450
 451         struct kref refcount;
 452
 453         /* Set when the interface is being unregistered. */
 454         bool in_shutdown;
 455
 456         /* Used for a list of interfaces. */
 457         struct list_head link;
 458
 459         /*
 460          * The list of upper layers that are using me.  seq_lock write
 461          * protects this.  Read protection is with srcu.
 462          */
 463         struct list_head users;
 464         struct srcu_struct users_srcu;
 465
 466         /* Used for wake ups at startup. */
 467         wait_queue_head_t waitq;
 468
 469         /*
 470          * Prevents the interface from being unregistered when the
 471          * interface is used by being looked up through the BMC
 472          * structure.
 473          */
 474         struct mutex bmc_reg_mutex;
 475
 476         struct bmc_device tmp_bmc;
 477         struct bmc_device *bmc;
 478         bool bmc_registered;
 479         struct list_head bmc_link;
 480         char *my_dev_name;
 481         bool in_bmc_register;  /* Handle recursive situations.  Yuck. */
 482         struct work_struct bmc_reg_work;
 483
 484         const struct ipmi_smi_handlers *handlers;
 485         void                     *send_info;
 486
 487         /* Driver-model device for the system interface. */
 488         struct device          *si_dev;
 489
 490         /*
 491          * A table of sequence numbers for this interface.  We use the
 492          * sequence numbers for IPMB messages that go out of the
 493          * interface to match them up with their responses.  A routine
 494          * is called periodically to time the items in this list.
 495          */
 496         spinlock_t       seq_lock;
 497         struct seq_table seq_table[IPMI_IPMB_NUM_SEQ];
 498         int curr_seq;
 499
 500         /*
 501          * Messages queued for delivery.  If delivery fails (out of memory
 502          * for instance), They will stay in here to be processed later in a
 503          * periodic timer interrupt.  The tasklet is for handling received
 504          * messages directly from the handler.
 505          */
 506         spinlock_t       waiting_rcv_msgs_lock;
 507         struct list_head waiting_rcv_msgs;
 508         atomic_t         watchdog_pretimeouts_to_deliver;
 509         struct tasklet_struct recv_tasklet;
 510
 511         spinlock_t             xmit_msgs_lock;
 512         struct list_head       xmit_msgs;
 513         struct ipmi_smi_msg    *curr_msg;
 514         struct list_head       hp_xmit_msgs;
 515
 516         /*
 517          * The list of command receivers that are registered for commands
 518          * on this interface.
 519          */
 520         struct mutex     cmd_rcvrs_mutex;
 521         struct list_head cmd_rcvrs;
 522
 523         /*
 524          * Events that were queues because no one was there to receive
 525          * them.
 526          */
 527         spinlock_t       events_lock; /* For dealing with event stuff. */
 528         struct list_head waiting_events;
 529         unsigned int     waiting_events_count; /* How many events in queue? */
 530         char             delivering_events;
 531         char             event_msg_printed;
 532         atomic_t         event_waiters;
 533         unsigned int     ticks_to_req_ev;
 534         int              last_needs_timer;
 535
 536         /*
 537          * The event receiver for my BMC, only really used at panic
 538          * shutdown as a place to store this.
 539          */
 540         unsigned char event_receiver;
 541         unsigned char event_receiver_lun;
 542         unsigned char local_sel_device;
 543         unsigned char local_event_generator;
 544
 545         /* For handling of maintenance mode. */
 546         int maintenance_mode;
 547         bool maintenance_mode_enable;
 548         int auto_maintenance_timeout;
 549         spinlock_t maintenance_mode_lock; /* Used in a timer... */
 550
 551         /*
 552          * If we are doing maintenance on something on IPMB, extend
 553          * the timeout time to avoid timeouts writing firmware and
 554          * such.
 555          */
 556         int ipmb_maintenance_mode_timeout;
 557
 558         /*
 559          * A cheap hack, if this is non-null and a message to an
 560          * interface comes in with a NULL user, call this routine with
 561          * it.  Note that the message will still be freed by the
 562          * caller.  This only works on the system interface.
 563          *
 564          * Protected by bmc_reg_mutex.
 565          */
 566         void (*null_user_handler)(struct ipmi_smi *intf,
 567                                   struct ipmi_recv_msg *msg);
 568
 569         /*
 570          * When we are scanning the channels for an SMI, this will
 571          * tell which channel we are scanning.
 572          */
 573         int curr_channel;
 574
 575         /* Channel information */
 576         struct ipmi_channel_set *channel_list;
 577         unsigned int curr_working_cset; /* First index into the following. */
 578         struct ipmi_channel_set wchannels[2];
 579         struct ipmi_my_addrinfo addrinfo[IPMI_MAX_CHANNELS];
 580         bool channels_ready;
 581
 582         atomic_t stats[IPMI_NUM_STATS];
 583
 584         /*
 585          * run_to_completion duplicate of smb_info, smi_info
 586          * and ipmi_serial_info structures. Used to decrease numbers of
 587          * parameters passed by "low" level IPMI code.
 588          */
 589         int run_to_completion;
 590 };
 591 #define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev)
 592
 593 static void __get_guid(struct ipmi_smi *intf);
 594 static void __ipmi_bmc_unregister(struct ipmi_smi *intf);
 595 static int __ipmi_bmc_register(struct ipmi_smi *intf,
 596                                struct ipmi_device_id *id,
 597                                bool guid_set, guid_t *guid, int intf_num);
 598 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id);
 599
 600
 601 /**
 602  * The driver model view of the IPMI messaging driver.
 603  */
 604 static struct platform_driver ipmidriver = {
 605         .driver = {
 606                 .name = "ipmi",
 607                 .bus = &platform_bus_type
 608         }
 609 };
 610 /*
 611  * This mutex keeps us from adding the same BMC twice.
 612  */
 613 static DEFINE_MUTEX(ipmidriver_mutex);
 614
 615 static LIST_HEAD(ipmi_interfaces);
 616 static DEFINE_MUTEX(ipmi_interfaces_mutex);
 617 struct srcu_struct ipmi_interfaces_srcu;
 618
 619 /*
 620  * List of watchers that want to know when smi's are added and deleted.
 621  */
 622 static LIST_HEAD(smi_watchers);
 623 static DEFINE_MUTEX(smi_watchers_mutex);
 624
 625 #define ipmi_inc_stat(intf, stat) \
 626         atomic_inc(&(intf)->stats[IPMI_STAT_ ## stat])
 627 #define ipmi_get_stat(intf, stat) \
 628         ((unsigned int) atomic_read(&(intf)->stats[IPMI_STAT_ ## stat]))
 629
 630 static const char * const addr_src_to_str[] = {
 631         "invalid", "hotmod", "hardcoded", "SPMI", "ACPI", "SMBIOS", "PCI",
 632         "device-tree", "platform"
 633 };
 634
 635 const char *ipmi_addr_src_to_str(enum ipmi_addr_src src)
 636 {
 637         if (src >= SI_LAST)
 638                 src = 0; /* Invalid */
 639         return addr_src_to_str[src];
 640 }
 641 EXPORT_SYMBOL(ipmi_addr_src_to_str);
 642
 643 static int is_lan_addr(struct ipmi_addr *addr)
 644 {
 645         return addr->addr_type == IPMI_LAN_ADDR_TYPE;
 646 }
 647
 648 static int is_ipmb_addr(struct ipmi_addr *addr)
 649 {
 650         return addr->addr_type == IPMI_IPMB_ADDR_TYPE;
 651 }
 652
 653 static int is_ipmb_bcast_addr(struct ipmi_addr *addr)
 654 {
 655         return addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE;
 656 }
 657
 658 static void free_recv_msg_list(struct list_head *q)
 659 {
 660         struct ipmi_recv_msg *msg, *msg2;
 661
 662         list_for_each_entry_safe(msg, msg2, q, link) {
 663                 list_del(&msg->link);
 664                 ipmi_free_recv_msg(msg);
 665         }
 666 }
 667
 668 static void free_smi_msg_list(struct list_head *q)
 669 {
 670         struct ipmi_smi_msg *msg, *msg2;
 671
 672         list_for_each_entry_safe(msg, msg2, q, link) {
 673                 list_del(&msg->link);
 674                 ipmi_free_smi_msg(msg);
 675         }
 676 }
 677
 678 static void clean_up_interface_data(struct ipmi_smi *intf)
 679 {
 680         int              i;
 681         struct cmd_rcvr  *rcvr, *rcvr2;
 682         struct list_head list;
 683
 684         tasklet_kill(&intf->recv_tasklet);
 685
 686         free_smi_msg_list(&intf->waiting_rcv_msgs);
 687         free_recv_msg_list(&intf->waiting_events);
 688
 689         /*
 690          * Wholesale remove all the entries from the list in the
 691          * interface and wait for RCU to know that none are in use.
 692          */
 693         mutex_lock(&intf->cmd_rcvrs_mutex);
 694         INIT_LIST_HEAD(&list);
 695         list_splice_init_rcu(&intf->cmd_rcvrs, &list, synchronize_rcu);
 696         mutex_unlock(&intf->cmd_rcvrs_mutex);
 697
 698         list_for_each_entry_safe(rcvr, rcvr2, &list, link)
 699                 kfree(rcvr);
 700
 701         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
 702                 if ((intf->seq_table[i].inuse)
 703                                         && (intf->seq_table[i].recv_msg))
 704                         ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
 705         }
 706 }
 707
 708 static void intf_free(struct kref *ref)
 709 {
 710         struct ipmi_smi *intf = container_of(ref, struct ipmi_smi, refcount);
 711
 712         clean_up_interface_data(intf);
 713         kfree(intf);
 714 }
 715
 716 struct watcher_entry {
 717         int              intf_num;
 718         struct ipmi_smi  *intf;
 719         struct list_head link;
 720 };
 721
 722 int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
 723 {
 724         struct ipmi_smi *intf;
 725         int index, rv;
 726
 727         /*
 728          * Make sure the driver is actually initialized, this handles
 729          * problems with initialization order.
 730          */
 731         rv = ipmi_init_msghandler();
 732         if (rv)
 733                 return rv;
 734
 735         mutex_lock(&smi_watchers_mutex);
 736
 737         list_add(&watcher->link, &smi_watchers);
 738
 739         index = srcu_read_lock(&ipmi_interfaces_srcu);
 740         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
 741                 int intf_num = READ_ONCE(intf->intf_num);
 742
 743                 if (intf_num == -1)
 744                         continue;
 745                 watcher->new_smi(intf_num, intf->si_dev);
 746         }
 747         srcu_read_unlock(&ipmi_interfaces_srcu, index);
 748
 749         mutex_unlock(&smi_watchers_mutex);
 750
 751         return 0;
 752 }
 753 EXPORT_SYMBOL(ipmi_smi_watcher_register);
 754
 755 int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher)
 756 {
 757         mutex_lock(&smi_watchers_mutex);
 758         list_del(&watcher->link);
 759         mutex_unlock(&smi_watchers_mutex);
 760         return 0;
 761 }
 762 EXPORT_SYMBOL(ipmi_smi_watcher_unregister);
 763
 764 /*
 765  * Must be called with smi_watchers_mutex held.
 766  */
 767 static void
 768 call_smi_watchers(int i, struct device *dev)
 769 {
 770         struct ipmi_smi_watcher *w;
 771
 772         mutex_lock(&smi_watchers_mutex);
 773         list_for_each_entry(w, &smi_watchers, link) {
 774                 if (try_module_get(w->owner)) {
 775                         w->new_smi(i, dev);
 776                         module_put(w->owner);
 777                 }
 778         }
 779         mutex_unlock(&smi_watchers_mutex);
 780 }
 781
 782 static int
 783 ipmi_addr_equal(struct ipmi_addr *addr1, struct ipmi_addr *addr2)
 784 {
 785         if (addr1->addr_type != addr2->addr_type)
 786                 return 0;
 787
 788         if (addr1->channel != addr2->channel)
 789                 return 0;
 790
 791         if (addr1->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
 792                 struct ipmi_system_interface_addr *smi_addr1
 793                     = (struct ipmi_system_interface_addr *) addr1;
 794                 struct ipmi_system_interface_addr *smi_addr2
 795                     = (struct ipmi_system_interface_addr *) addr2;
 796                 return (smi_addr1->lun == smi_addr2->lun);
 797         }
 798
 799         if (is_ipmb_addr(addr1) || is_ipmb_bcast_addr(addr1)) {
 800                 struct ipmi_ipmb_addr *ipmb_addr1
 801                     = (struct ipmi_ipmb_addr *) addr1;
 802                 struct ipmi_ipmb_addr *ipmb_addr2
 803                     = (struct ipmi_ipmb_addr *) addr2;
 804
 805                 return ((ipmb_addr1->slave_addr == ipmb_addr2->slave_addr)
 806                         && (ipmb_addr1->lun == ipmb_addr2->lun));
 807         }
 808
 809         if (is_lan_addr(addr1)) {
 810                 struct ipmi_lan_addr *lan_addr1
 811                         = (struct ipmi_lan_addr *) addr1;
 812                 struct ipmi_lan_addr *lan_addr2
 813                     = (struct ipmi_lan_addr *) addr2;
 814
 815                 return ((lan_addr1->remote_SWID == lan_addr2->remote_SWID)
 816                         && (lan_addr1->local_SWID == lan_addr2->local_SWID)
 817                         && (lan_addr1->session_handle
 818                             == lan_addr2->session_handle)
 819                         && (lan_addr1->lun == lan_addr2->lun));
 820         }
 821
 822         return 1;
 823 }
 824
 825 int ipmi_validate_addr(struct ipmi_addr *addr, int len)
 826 {
 827         if (len < sizeof(struct ipmi_system_interface_addr))
 828                 return -EINVAL;
 829
 830         if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
 831                 if (addr->channel != IPMI_BMC_CHANNEL)
 832                         return -EINVAL;
 833                 return 0;
 834         }
 835
 836         if ((addr->channel == IPMI_BMC_CHANNEL)
 837             || (addr->channel >= IPMI_MAX_CHANNELS)
 838             || (addr->channel < 0))
 839                 return -EINVAL;
 840
 841         if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
 842                 if (len < sizeof(struct ipmi_ipmb_addr))
 843                         return -EINVAL;
 844                 return 0;
 845         }
 846
 847         if (is_lan_addr(addr)) {
 848                 if (len < sizeof(struct ipmi_lan_addr))
 849                         return -EINVAL;
 850                 return 0;
 851         }
 852
 853         return -EINVAL;
 854 }
 855 EXPORT_SYMBOL(ipmi_validate_addr);
 856
 857 unsigned int ipmi_addr_length(int addr_type)
 858 {
 859         if (addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
 860                 return sizeof(struct ipmi_system_interface_addr);
 861
 862         if ((addr_type == IPMI_IPMB_ADDR_TYPE)
 863                         || (addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE))
 864                 return sizeof(struct ipmi_ipmb_addr);
 865
 866         if (addr_type == IPMI_LAN_ADDR_TYPE)
 867                 return sizeof(struct ipmi_lan_addr);
 868
 869         return 0;
 870 }
 871 EXPORT_SYMBOL(ipmi_addr_length);
 872
 873 static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
 874 {
 875         int rv = 0;
 876
 877         if (!msg->user) {
 878                 /* Special handling for NULL users. */
 879                 if (intf->null_user_handler) {
 880                         intf->null_user_handler(intf, msg);
 881                 } else {
 882                         /* No handler, so give up. */
 883                         rv = -EINVAL;
 884                 }
 885                 ipmi_free_recv_msg(msg);
 886         } else if (!oops_in_progress) {
 887                 /*
 888                  * If we are running in the panic context, calling the
 889                  * receive handler doesn't much meaning and has a deadlock
 890                  * risk.  At this moment, simply skip it in that case.
 891                  */
 892                 int index;
 893                 struct ipmi_user *user = acquire_ipmi_user(msg->user, &index);
 894
 895                 if (user) {
 896                         user->handler->ipmi_recv_hndl(msg, user->handler_data);
 897                         release_ipmi_user(user, index);
 898                 } else {
 899                         /* User went away, give up. */
 900                         ipmi_free_recv_msg(msg);
 901                         rv = -EINVAL;
 902                 }
 903         }
 904
 905         return rv;
 906 }
 907
 908 static void deliver_local_response(struct ipmi_smi *intf,
 909                                    struct ipmi_recv_msg *msg)
 910 {
 911         if (deliver_response(intf, msg))
 912                 ipmi_inc_stat(intf, unhandled_local_responses);
 913         else
 914                 ipmi_inc_stat(intf, handled_local_responses);
 915 }
 916
 917 static void deliver_err_response(struct ipmi_smi *intf,
 918                                  struct ipmi_recv_msg *msg, int err)
 919 {
 920         msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
 921         msg->msg_data[0] = err;
 922         msg->msg.netfn |= 1; /* Convert to a response. */
 923         msg->msg.data_len = 1;
 924         msg->msg.data = msg->msg_data;
 925         deliver_local_response(intf, msg);
 926 }
 927
 928 /*
 929  * Find the next sequence number not being used and add the given
 930  * message with the given timeout to the sequence table.  This must be
 931  * called with the interface's seq_lock held.
 932  */
 933 static int intf_next_seq(struct ipmi_smi      *intf,
 934                          struct ipmi_recv_msg *recv_msg,
 935                          unsigned long        timeout,
 936                          int                  retries,
 937                          int                  broadcast,
 938                          unsigned char        *seq,
 939                          long                 *seqid)
 940 {
 941         int          rv = 0;
 942         unsigned int i;
 943
 944         if (timeout == 0)
 945                 timeout = default_retry_ms;
 946         if (retries < 0)
 947                 retries = default_max_retries;
 948
 949         for (i = intf->curr_seq; (i+1)%IPMI_IPMB_NUM_SEQ != intf->curr_seq;
 950                                         i = (i+1)%IPMI_IPMB_NUM_SEQ) {
 951                 if (!intf->seq_table[i].inuse)
 952                         break;
 953         }
 954
 955         if (!intf->seq_table[i].inuse) {
 956                 intf->seq_table[i].recv_msg = recv_msg;
 957
 958                 /*
 959                  * Start with the maximum timeout, when the send response
 960                  * comes in we will start the real timer.
 961                  */
 962                 intf->seq_table[i].timeout = MAX_MSG_TIMEOUT;
 963                 intf->seq_table[i].orig_timeout = timeout;
 964                 intf->seq_table[i].retries_left = retries;
 965                 intf->seq_table[i].broadcast = broadcast;
 966                 intf->seq_table[i].inuse = 1;
 967                 intf->seq_table[i].seqid = NEXT_SEQID(intf->seq_table[i].seqid);
 968                 *seq = i;
 969                 *seqid = intf->seq_table[i].seqid;
 970                 intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
 971                 need_waiter(intf);
 972         } else {
 973                 rv = -EAGAIN;
 974         }
 975
 976         return rv;
 977 }
 978
 979 /*
 980  * Return the receive message for the given sequence number and
 981  * release the sequence number so it can be reused.  Some other data
 982  * is passed in to be sure the message matches up correctly (to help
 983  * guard against message coming in after their timeout and the
 984  * sequence number being reused).
 985  */
 986 static int intf_find_seq(struct ipmi_smi      *intf,
 987                          unsigned char        seq,
 988                          short                channel,
 989                          unsigned char        cmd,
 990                          unsigned char        netfn,
 991                          struct ipmi_addr     *addr,
 992                          struct ipmi_recv_msg **recv_msg)
 993 {
 994         int           rv = -ENODEV;
 995         unsigned long flags;
 996
 997         if (seq >= IPMI_IPMB_NUM_SEQ)
 998                 return -EINVAL;
 999
1000         spin_lock_irqsave(&intf->seq_lock, flags);
1001         if (intf->seq_table[seq].inuse) {
1002                 struct ipmi_recv_msg *msg = intf->seq_table[seq].recv_msg;
1003
1004                 if ((msg->addr.channel == channel) && (msg->msg.cmd == cmd)
1005                                 && (msg->msg.netfn == netfn)
1006                                 && (ipmi_addr_equal(addr, &msg->addr))) {
1007                         *recv_msg = msg;
1008                         intf->seq_table[seq].inuse = 0;
1009                         rv = 0;
1010                 }
1011         }
1012         spin_unlock_irqrestore(&intf->seq_lock, flags);
1013
1014         return rv;
1015 }
1016
1017
1018 /* Start the timer for a specific sequence table entry. */
1019 static int intf_start_seq_timer(struct ipmi_smi *intf,
1020                                 long       msgid)
1021 {
1022         int           rv = -ENODEV;
1023         unsigned long flags;
1024         unsigned char seq;
1025         unsigned long seqid;
1026
1027
1028         GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1029
1030         spin_lock_irqsave(&intf->seq_lock, flags);
1031         /*
1032          * We do this verification because the user can be deleted
1033          * while a message is outstanding.
1034          */
1035         if ((intf->seq_table[seq].inuse)
1036                                 && (intf->seq_table[seq].seqid == seqid)) {
1037                 struct seq_table *ent = &intf->seq_table[seq];
1038                 ent->timeout = ent->orig_timeout;
1039                 rv = 0;
1040         }
1041         spin_unlock_irqrestore(&intf->seq_lock, flags);
1042
1043         return rv;
1044 }
1045
1046 /* Got an error for the send message for a specific sequence number. */
1047 static int intf_err_seq(struct ipmi_smi *intf,
1048                         long         msgid,
1049                         unsigned int err)
1050 {
1051         int                  rv = -ENODEV;
1052         unsigned long        flags;
1053         unsigned char        seq;
1054         unsigned long        seqid;
1055         struct ipmi_recv_msg *msg = NULL;
1056
1057
1058         GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1059
1060         spin_lock_irqsave(&intf->seq_lock, flags);
1061         /*
1062          * We do this verification because the user can be deleted
1063          * while a message is outstanding.
1064          */
1065         if ((intf->seq_table[seq].inuse)
1066                                 && (intf->seq_table[seq].seqid == seqid)) {
1067                 struct seq_table *ent = &intf->seq_table[seq];
1068
1069                 ent->inuse = 0;
1070                 msg = ent->recv_msg;
1071                 rv = 0;
1072         }
1073         spin_unlock_irqrestore(&intf->seq_lock, flags);
1074
1075         if (msg)
1076                 deliver_err_response(intf, msg, err);
1077
1078         return rv;
1079 }
1080
1081
1082 int ipmi_create_user(unsigned int          if_num,
1083                      const struct ipmi_user_hndl *handler,
1084                      void                  *handler_data,
1085                      struct ipmi_user      **user)
1086 {
1087         unsigned long flags;
1088         struct ipmi_user *new_user;
1089         int           rv, index;
1090         struct ipmi_smi *intf;
1091
1092         /*
1093          * There is no module usecount here, because it's not
1094          * required.  Since this can only be used by and called from
1095          * other modules, they will implicitly use this module, and
1096          * thus this can't be removed unless the other modules are
1097          * removed.
1098          */
1099
1100         if (handler == NULL)
1101                 return -EINVAL;
1102
1103         /*
1104          * Make sure the driver is actually initialized, this handles
1105          * problems with initialization order.
1106          */
1107         rv = ipmi_init_msghandler();
1108         if (rv)
1109                 return rv;
1110
1111         new_user = kmalloc(sizeof(*new_user), GFP_KERNEL);
1112         if (!new_user)
1113                 return -ENOMEM;
1114
1115         index = srcu_read_lock(&ipmi_interfaces_srcu);
1116         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1117                 if (intf->intf_num == if_num)
1118                         goto found;
1119         }
1120         /* Not found, return an error */
1121         rv = -EINVAL;
1122         goto out_kfree;
1123
1124  found:
1125         rv = init_srcu_struct(&new_user->release_barrier);
1126         if (rv)
1127                 goto out_kfree;
1128
1129         /* Note that each existing user holds a refcount to the interface. */
1130         kref_get(&intf->refcount);
1131
1132         kref_init(&new_user->refcount);
1133         new_user->handler = handler;
1134         new_user->handler_data = handler_data;
1135         new_user->intf = intf;
1136         new_user->gets_events = false;
1137
1138         rcu_assign_pointer(new_user->self, new_user);
1139         spin_lock_irqsave(&intf->seq_lock, flags);
1140         list_add_rcu(&new_user->link, &intf->users);
1141         spin_unlock_irqrestore(&intf->seq_lock, flags);
1142         if (handler->ipmi_watchdog_pretimeout) {
1143                 /* User wants pretimeouts, so make sure to watch for them. */
1144                 if (atomic_inc_return(&intf->event_waiters) == 1)
1145                         need_waiter(intf);
1146         }
1147         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1148         *user = new_user;
1149         return 0;
1150
1151 out_kfree:
1152         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1153         kfree(new_user);
1154         return rv;
1155 }
1156 EXPORT_SYMBOL(ipmi_create_user);
1157
1158 int ipmi_get_smi_info(int if_num, struct ipmi_smi_info *data)
1159 {
1160         int rv, index;
1161         struct ipmi_smi *intf;
1162
1163         index = srcu_read_lock(&ipmi_interfaces_srcu);
1164         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1165                 if (intf->intf_num == if_num)
1166                         goto found;
1167         }
1168         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1169
1170         /* Not found, return an error */
1171         return -EINVAL;
1172
1173 found:
1174         if (!intf->handlers->get_smi_info)
1175                 rv = -ENOTTY;
1176         else
1177                 rv = intf->handlers->get_smi_info(intf->send_info, data);
1178         srcu_read_unlock(&ipmi_interfaces_srcu, index);
1179
1180         return rv;
1181 }
1182 EXPORT_SYMBOL(ipmi_get_smi_info);
1183
1184 static void free_user(struct kref *ref)
1185 {
1186         struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount);
1187         cleanup_srcu_struct(&user->release_barrier);
1188         kfree(user);
1189 }
1190
1191 static void _ipmi_destroy_user(struct ipmi_user *user)
1192 {
1193         struct ipmi_smi  *intf = user->intf;
1194         int              i;
1195         unsigned long    flags;
1196         struct cmd_rcvr  *rcvr;
1197         struct cmd_rcvr  *rcvrs = NULL;
1198
1199         if (!acquire_ipmi_user(user, &i)) {
1200                 /*
1201                  * The user has already been cleaned up, just make sure
1202                  * nothing is using it and return.
1203                  */
1204                 synchronize_srcu(&user->release_barrier);
1205                 return;
1206         }
1207
1208         rcu_assign_pointer(user->self, NULL);
1209         release_ipmi_user(user, i);
1210
1211         synchronize_srcu(&user->release_barrier);
1212
1213         if (user->handler->shutdown)
1214                 user->handler->shutdown(user->handler_data);
1215
1216         if (user->handler->ipmi_watchdog_pretimeout)
1217                 atomic_dec(&intf->event_waiters);
1218
1219         if (user->gets_events)
1220                 atomic_dec(&intf->event_waiters);
1221
1222         /* Remove the user from the interface's sequence table. */
1223         spin_lock_irqsave(&intf->seq_lock, flags);
1224         list_del_rcu(&user->link);
1225
1226         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
1227                 if (intf->seq_table[i].inuse
1228                     && (intf->seq_table[i].recv_msg->user == user)) {
1229                         intf->seq_table[i].inuse = 0;
1230                         ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
1231                 }
1232         }
1233         spin_unlock_irqrestore(&intf->seq_lock, flags);
1234
1235         /*
1236          * Remove the user from the command receiver's table.  First
1237          * we build a list of everything (not using the standard link,
1238          * since other things may be using it till we do
1239          * synchronize_srcu()) then free everything in that list.
1240          */
1241         mutex_lock(&intf->cmd_rcvrs_mutex);
1242         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
1243                 if (rcvr->user == user) {
1244                         list_del_rcu(&rcvr->link);
1245                         rcvr->next = rcvrs;
1246                         rcvrs = rcvr;
1247                 }
1248         }
1249         mutex_unlock(&intf->cmd_rcvrs_mutex);
1250         synchronize_rcu();
1251         while (rcvrs) {
1252                 rcvr = rcvrs;
1253                 rcvrs = rcvr->next;
1254                 kfree(rcvr);
1255         }
1256
1257         kref_put(&intf->refcount, intf_free);
1258 }
1259
1260 int ipmi_destroy_user(struct ipmi_user *user)
1261 {
1262         _ipmi_destroy_user(user);
1263
1264         kref_put(&user->refcount, free_user);
1265
1266         return 0;
1267 }
1268 EXPORT_SYMBOL(ipmi_destroy_user);
1269
1270 int ipmi_get_version(struct ipmi_user *user,
1271                      unsigned char *major,
1272                      unsigned char *minor)
1273 {
1274         struct ipmi_device_id id;
1275         int rv, index;
1276
1277         user = acquire_ipmi_user(user, &index);
1278         if (!user)
1279                 return -ENODEV;
1280
1281         rv = bmc_get_device_id(user->intf, NULL, &id, NULL, NULL);
1282         if (!rv) {
1283                 *major = ipmi_version_major(&id);
1284                 *minor = ipmi_version_minor(&id);
1285         }
1286         release_ipmi_user(user, index);
1287
1288         return rv;
1289 }
1290 EXPORT_SYMBOL(ipmi_get_version);
1291
1292 int ipmi_set_my_address(struct ipmi_user *user,
1293                         unsigned int  channel,
1294                         unsigned char address)
1295 {
1296         int index, rv = 0;
1297
1298         user = acquire_ipmi_user(user, &index);
1299         if (!user)
1300                 return -ENODEV;
1301
1302         if (channel >= IPMI_MAX_CHANNELS) {
1303                 rv = -EINVAL;
1304         } else {
1305                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1306                 user->intf->addrinfo[channel].address = address;
1307         }
1308         release_ipmi_user(user, index);
1309
1310         return rv;
1311 }
1312 EXPORT_SYMBOL(ipmi_set_my_address);
1313
1314 int ipmi_get_my_address(struct ipmi_user *user,
1315                         unsigned int  channel,
1316                         unsigned char *address)
1317 {
1318         int index, rv = 0;
1319
1320         user = acquire_ipmi_user(user, &index);
1321         if (!user)
1322                 return -ENODEV;
1323
1324         if (channel >= IPMI_MAX_CHANNELS) {
1325                 rv = -EINVAL;
1326         } else {
1327                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1328                 *address = user->intf->addrinfo[channel].address;
1329         }
1330         release_ipmi_user(user, index);
1331
1332         return rv;
1333 }
1334 EXPORT_SYMBOL(ipmi_get_my_address);
1335
1336 int ipmi_set_my_LUN(struct ipmi_user *user,
1337                     unsigned int  channel,
1338                     unsigned char LUN)
1339 {
1340         int index, rv = 0;
1341
1342         user = acquire_ipmi_user(user, &index);
1343         if (!user)
1344                 return -ENODEV;
1345
1346         if (channel >= IPMI_MAX_CHANNELS) {
1347                 rv = -EINVAL;
1348         } else {
1349                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1350                 user->intf->addrinfo[channel].lun = LUN & 0x3;
1351         }
1352         release_ipmi_user(user, index);
1353
1354         return rv;
1355 }
1356 EXPORT_SYMBOL(ipmi_set_my_LUN);
1357
1358 int ipmi_get_my_LUN(struct ipmi_user *user,
1359                     unsigned int  channel,
1360                     unsigned char *address)
1361 {
1362         int index, rv = 0;
1363
1364         user = acquire_ipmi_user(user, &index);
1365         if (!user)
1366                 return -ENODEV;
1367
1368         if (channel >= IPMI_MAX_CHANNELS) {
1369                 rv = -EINVAL;
1370         } else {
1371                 channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1372                 *address = user->intf->addrinfo[channel].lun;
1373         }
1374         release_ipmi_user(user, index);
1375
1376         return rv;
1377 }
1378 EXPORT_SYMBOL(ipmi_get_my_LUN);
1379
1380 int ipmi_get_maintenance_mode(struct ipmi_user *user)
1381 {
1382         int mode, index;
1383         unsigned long flags;
1384
1385         user = acquire_ipmi_user(user, &index);
1386         if (!user)
1387                 return -ENODEV;
1388
1389         spin_lock_irqsave(&user->intf->maintenance_mode_lock, flags);
1390         mode = user->intf->maintenance_mode;
1391         spin_unlock_irqrestore(&user->intf->maintenance_mode_lock, flags);
1392         release_ipmi_user(user, index);
1393
1394         return mode;
1395 }
1396 EXPORT_SYMBOL(ipmi_get_maintenance_mode);
1397
1398 static void maintenance_mode_update(struct ipmi_smi *intf)
1399 {
1400         if (intf->handlers->set_maintenance_mode)
1401                 intf->handlers->set_maintenance_mode(
1402                         intf->send_info, intf->maintenance_mode_enable);
1403 }
1404
1405 int ipmi_set_maintenance_mode(struct ipmi_user *user, int mode)
1406 {
1407         int rv = 0, index;
1408         unsigned long flags;
1409         struct ipmi_smi *intf = user->intf;
1410
1411         user = acquire_ipmi_user(user, &index);
1412         if (!user)
1413                 return -ENODEV;
1414
1415         spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1416         if (intf->maintenance_mode != mode) {
1417                 switch (mode) {
1418                 case IPMI_MAINTENANCE_MODE_AUTO:
1419                         intf->maintenance_mode_enable
1420                                 = (intf->auto_maintenance_timeout > 0);
1421                         break;
1422
1423                 case IPMI_MAINTENANCE_MODE_OFF:
1424                         intf->maintenance_mode_enable = false;
1425                         break;
1426
1427                 case IPMI_MAINTENANCE_MODE_ON:
1428                         intf->maintenance_mode_enable = true;
1429                         break;
1430
1431                 default:
1432                         rv = -EINVAL;
1433                         goto out_unlock;
1434                 }
1435                 intf->maintenance_mode = mode;
1436
1437                 maintenance_mode_update(intf);
1438         }
1439  out_unlock:
1440         spin_unlock_irqrestore(&intf->maintenance_mode_lock, flags);
1441         release_ipmi_user(user, index);
1442
1443         return rv;
1444 }
1445 EXPORT_SYMBOL(ipmi_set_maintenance_mode);
1446
1447 int ipmi_set_gets_events(struct ipmi_user *user, bool val)
1448 {
1449         unsigned long        flags;
1450         struct ipmi_smi      *intf = user->intf;
1451         struct ipmi_recv_msg *msg, *msg2;
1452         struct list_head     msgs;
1453         int index;
1454
1455         user = acquire_ipmi_user(user, &index);
1456         if (!user)
1457                 return -ENODEV;
1458
1459         INIT_LIST_HEAD(&msgs);
1460
1461         spin_lock_irqsave(&intf->events_lock, flags);
1462         if (user->gets_events == val)
1463                 goto out;
1464
1465         user->gets_events = val;
1466
1467         if (val) {
1468                 if (atomic_inc_return(&intf->event_waiters) == 1)
1469                         need_waiter(intf);
1470         } else {
1471                 atomic_dec(&intf->event_waiters);
1472         }
1473
1474         if (intf->delivering_events)
1475                 /*
1476                  * Another thread is delivering events for this, so
1477                  * let it handle any new events.
1478                  */
1479                 goto out;
1480
1481         /* Deliver any queued events. */
1482         while (user->gets_events && !list_empty(&intf->waiting_events)) {
1483                 list_for_each_entry_safe(msg, msg2, &intf->waiting_events, link)
1484                         list_move_tail(&msg->link, &msgs);
1485                 intf->waiting_events_count = 0;
1486                 if (intf->event_msg_printed) {
1487                         dev_warn(intf->si_dev, "Event queue no longer full\n");
1488                         intf->event_msg_printed = 0;
1489                 }
1490
1491                 intf->delivering_events = 1;
1492                 spin_unlock_irqrestore(&intf->events_lock, flags);
1493
1494                 list_for_each_entry_safe(msg, msg2, &msgs, link) {
1495                         msg->user = user;
1496                         kref_get(&user->refcount);
1497                         deliver_local_response(intf, msg);
1498                 }
1499
1500                 spin_lock_irqsave(&intf->events_lock, flags);
1501                 intf->delivering_events = 0;
1502         }
1503
1504  out:
1505         spin_unlock_irqrestore(&intf->events_lock, flags);
1506         release_ipmi_user(user, index);
1507
1508         return 0;
1509 }
1510 EXPORT_SYMBOL(ipmi_set_gets_events);
1511
1512 static struct cmd_rcvr *find_cmd_rcvr(struct ipmi_smi *intf,
1513                                       unsigned char netfn,
1514                                       unsigned char cmd,
1515                                       unsigned char chan)
1516 {
1517         struct cmd_rcvr *rcvr;
1518
1519         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
1520                 if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1521                                         && (rcvr->chans & (1 << chan)))
1522                         return rcvr;
1523         }
1524         return NULL;
1525 }
1526
1527 static int is_cmd_rcvr_exclusive(struct ipmi_smi *intf,
1528                                  unsigned char netfn,
1529                                  unsigned char cmd,
1530                                  unsigned int  chans)
1531 {
1532         struct cmd_rcvr *rcvr;
1533
1534         list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) {
1535                 if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1536                                         && (rcvr->chans & chans))
1537                         return 0;
1538         }
1539         return 1;
1540 }
1541
1542 int ipmi_register_for_cmd(struct ipmi_user *user,
1543                           unsigned char netfn,
1544                           unsigned char cmd,
1545                           unsigned int  chans)
1546 {
1547         struct ipmi_smi *intf = user->intf;
1548         struct cmd_rcvr *rcvr;
1549         int rv = 0, index;
1550
1551         user = acquire_ipmi_user(user, &index);
1552         if (!user)
1553                 return -ENODEV;
1554
1555         rcvr = kmalloc(sizeof(*rcvr), GFP_KERNEL);
1556         if (!rcvr) {
1557                 rv = -ENOMEM;
1558                 goto out_release;
1559         }
1560         rcvr->cmd = cmd;
1561         rcvr->netfn = netfn;
1562         rcvr->chans = chans;
1563         rcvr->user = user;
1564
1565         mutex_lock(&intf->cmd_rcvrs_mutex);
1566         /* Make sure the command/netfn is not already registered. */
1567         if (!is_cmd_rcvr_exclusive(intf, netfn, cmd, chans)) {
1568                 rv = -EBUSY;
1569                 goto out_unlock;
1570         }
1571
1572         if (atomic_inc_return(&intf->event_waiters) == 1)
1573                 need_waiter(intf);
1574
1575         list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
1576
1577 out_unlock:
1578         mutex_unlock(&intf->cmd_rcvrs_mutex);
1579         if (rv)
1580                 kfree(rcvr);
1581 out_release:
1582         release_ipmi_user(user, index);
1583
1584         return rv;
1585 }
1586 EXPORT_SYMBOL(ipmi_register_for_cmd);
1587
1588 int ipmi_unregister_for_cmd(struct ipmi_user *user,
1589                             unsigned char netfn,
1590                             unsigned char cmd,
1591                             unsigned int  chans)
1592 {
1593         struct ipmi_smi *intf = user->intf;
1594         struct cmd_rcvr *rcvr;
1595         struct cmd_rcvr *rcvrs = NULL;
1596         int i, rv = -ENOENT, index;
1597
1598         user = acquire_ipmi_user(user, &index);
1599         if (!user)
1600                 return -ENODEV;
1601
1602         mutex_lock(&intf->cmd_rcvrs_mutex);
1603         for (i = 0; i < IPMI_NUM_CHANNELS; i++) {
1604                 if (((1 << i) & chans) == 0)
1605                         continue;
1606                 rcvr = find_cmd_rcvr(intf, netfn, cmd, i);
1607                 if (rcvr == NULL)
1608                         continue;
1609                 if (rcvr->user == user) {
1610                         rv = 0;
1611                         rcvr->chans &= ~chans;
1612                         if (rcvr->chans == 0) {
1613                                 list_del_rcu(&rcvr->link);
1614                                 rcvr->next = rcvrs;
1615                                 rcvrs = rcvr;
1616                         }
1617                 }
1618         }
1619         mutex_unlock(&intf->cmd_rcvrs_mutex);
1620         synchronize_rcu();
1621         release_ipmi_user(user, index);
1622         while (rcvrs) {
1623                 atomic_dec(&intf->event_waiters);
1624                 rcvr = rcvrs;
1625                 rcvrs = rcvr->next;
1626                 kfree(rcvr);
1627         }
1628
1629         return rv;
1630 }
1631 EXPORT_SYMBOL(ipmi_unregister_for_cmd);
1632
1633 static unsigned char
1634 ipmb_checksum(unsigned char *data, int size)
1635 {
1636         unsigned char csum = 0;
1637
1638         for (; size > 0; size--, data++)
1639                 csum += *data;
1640
1641         return -csum;
1642 }
1643
1644 static inline void format_ipmb_msg(struct ipmi_smi_msg   *smi_msg,
1645                                    struct kernel_ipmi_msg *msg,
1646                                    struct ipmi_ipmb_addr *ipmb_addr,
1647                                    long                  msgid,
1648                                    unsigned char         ipmb_seq,
1649                                    int                   broadcast,
1650                                    unsigned char         source_address,
1651                                    unsigned char         source_lun)
1652 {
1653         int i = broadcast;
1654
1655         /* Format the IPMB header data. */
1656         smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1657         smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1658         smi_msg->data[2] = ipmb_addr->channel;
1659         if (broadcast)
1660                 smi_msg->data[3] = 0;
1661         smi_msg->data[i+3] = ipmb_addr->slave_addr;
1662         smi_msg->data[i+4] = (msg->netfn << 2) | (ipmb_addr->lun & 0x3);
1663         smi_msg->data[i+5] = ipmb_checksum(&smi_msg->data[i + 3], 2);
1664         smi_msg->data[i+6] = source_address;
1665         smi_msg->data[i+7] = (ipmb_seq << 2) | source_lun;
1666         smi_msg->data[i+8] = msg->cmd;
1667
1668         /* Now tack on the data to the message. */
1669         if (msg->data_len > 0)
1670                 memcpy(&smi_msg->data[i + 9], msg->data, msg->data_len);
1671         smi_msg->data_size = msg->data_len + 9;
1672
1673         /* Now calculate the checksum and tack it on. */
1674         smi_msg->data[i+smi_msg->data_size]
1675                 = ipmb_checksum(&smi_msg->data[i + 6], smi_msg->data_size - 6);
1676
1677         /*
1678          * Add on the checksum size and the offset from the
1679          * broadcast.
1680          */
1681         smi_msg->data_size += 1 + i;
1682
1683         smi_msg->msgid = msgid;
1684 }
1685
1686 static inline void format_lan_msg(struct ipmi_smi_msg   *smi_msg,
1687                                   struct kernel_ipmi_msg *msg,
1688                                   struct ipmi_lan_addr  *lan_addr,
1689                                   long                  msgid,
1690                                   unsigned char         ipmb_seq,
1691                                   unsigned char         source_lun)
1692 {
1693         /* Format the IPMB header data. */
1694         smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1695         smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1696         smi_msg->data[2] = lan_addr->channel;
1697         smi_msg->data[3] = lan_addr->session_handle;
1698         smi_msg->data[4] = lan_addr->remote_SWID;
1699         smi_msg->data[5] = (msg->netfn << 2) | (lan_addr->lun & 0x3);
1700         smi_msg->data[6] = ipmb_checksum(&smi_msg->data[4], 2);
1701         smi_msg->data[7] = lan_addr->local_SWID;
1702         smi_msg->data[8] = (ipmb_seq << 2) | source_lun;
1703         smi_msg->data[9] = msg->cmd;
1704
1705         /* Now tack on the data to the message. */
1706         if (msg->data_len > 0)
1707                 memcpy(&smi_msg->data[10], msg->data, msg->data_len);
1708         smi_msg->data_size = msg->data_len + 10;
1709
1710         /* Now calculate the checksum and tack it on. */
1711         smi_msg->data[smi_msg->data_size]
1712                 = ipmb_checksum(&smi_msg->data[7], smi_msg->data_size - 7);
1713
1714         /*
1715          * Add on the checksum size and the offset from the
1716          * broadcast.
1717          */
1718         smi_msg->data_size += 1;
1719
1720         smi_msg->msgid = msgid;
1721 }
1722
1723 static struct ipmi_smi_msg *smi_add_send_msg(struct ipmi_smi *intf,
1724                                              struct ipmi_smi_msg *smi_msg,
1725                                              int priority)
1726 {
1727         if (intf->curr_msg) {
1728                 if (priority > 0)
1729                         list_add_tail(&smi_msg->link, &intf->hp_xmit_msgs);
1730                 else
1731                         list_add_tail(&smi_msg->link, &intf->xmit_msgs);
1732                 smi_msg = NULL;
1733         } else {
1734                 intf->curr_msg = smi_msg;
1735         }
1736
1737         return smi_msg;
1738 }
1739
1740
1741 static void smi_send(struct ipmi_smi *intf,
1742                      const struct ipmi_smi_handlers *handlers,
1743                      struct ipmi_smi_msg *smi_msg, int priority)
1744 {
1745         int run_to_completion = intf->run_to_completion;
1746
1747         if (run_to_completion) {
1748                 smi_msg = smi_add_send_msg(intf, smi_msg, priority);
1749         } else {
1750                 unsigned long flags;
1751
1752                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
1753                 smi_msg = smi_add_send_msg(intf, smi_msg, priority);
1754                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
1755         }
1756
1757         if (smi_msg)
1758                 handlers->sender(intf->send_info, smi_msg);
1759 }
1760
1761 static bool is_maintenance_mode_cmd(struct kernel_ipmi_msg *msg)
1762 {
1763         return (((msg->netfn == IPMI_NETFN_APP_REQUEST)
1764                  && ((msg->cmd == IPMI_COLD_RESET_CMD)
1765                      || (msg->cmd == IPMI_WARM_RESET_CMD)))
1766                 || (msg->netfn == IPMI_NETFN_FIRMWARE_REQUEST));
1767 }
1768
1769 static int i_ipmi_req_sysintf(struct ipmi_smi        *intf,
1770                               struct ipmi_addr       *addr,
1771                               long                   msgid,
1772                               struct kernel_ipmi_msg *msg,
1773                               struct ipmi_smi_msg    *smi_msg,
1774                               struct ipmi_recv_msg   *recv_msg,
1775                               int                    retries,
1776                               unsigned int           retry_time_ms)
1777 {
1778         struct ipmi_system_interface_addr *smi_addr;
1779
1780         if (msg->netfn & 1)
1781                 /* Responses are not allowed to the SMI. */
1782                 return -EINVAL;
1783
1784         smi_addr = (struct ipmi_system_interface_addr *) addr;
1785         if (smi_addr->lun > 3) {
1786                 ipmi_inc_stat(intf, sent_invalid_commands);
1787                 return -EINVAL;
1788         }
1789
1790         memcpy(&recv_msg->addr, smi_addr, sizeof(*smi_addr));
1791
1792         if ((msg->netfn == IPMI_NETFN_APP_REQUEST)
1793             && ((msg->cmd == IPMI_SEND_MSG_CMD)
1794                 || (msg->cmd == IPMI_GET_MSG_CMD)
1795                 || (msg->cmd == IPMI_READ_EVENT_MSG_BUFFER_CMD))) {
1796                 /*
1797                  * We don't let the user do these, since we manage
1798                  * the sequence numbers.
1799                  */
1800                 ipmi_inc_stat(intf, sent_invalid_commands);
1801                 return -EINVAL;
1802         }
1803
1804         if (is_maintenance_mode_cmd(msg)) {
1805                 unsigned long flags;
1806
1807                 spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1808                 intf->auto_maintenance_timeout
1809                         = maintenance_mode_timeout_ms;
1810                 if (!intf->maintenance_mode
1811                     && !intf->maintenance_mode_enable) {
1812                         intf->maintenance_mode_enable = true;
1813                         maintenance_mode_update(intf);
1814                 }
1815                 spin_unlock_irqrestore(&intf->maintenance_mode_lock,
1816                                        flags);
1817         }
1818
1819         if (msg->data_len + 2 > IPMI_MAX_MSG_LENGTH) {
1820                 ipmi_inc_stat(intf, sent_invalid_commands);
1821                 return -EMSGSIZE;
1822         }
1823
1824         smi_msg->data[0] = (msg->netfn << 2) | (smi_addr->lun & 0x3);
1825         smi_msg->data[1] = msg->cmd;
1826         smi_msg->msgid = msgid;
1827         smi_msg->user_data = recv_msg;
1828         if (msg->data_len > 0)
1829                 memcpy(&smi_msg->data[2], msg->data, msg->data_len);
1830         smi_msg->data_size = msg->data_len + 2;
1831         ipmi_inc_stat(intf, sent_local_commands);
1832
1833         return 0;
1834 }
1835
1836 static int i_ipmi_req_ipmb(struct ipmi_smi        *intf,
1837                            struct ipmi_addr       *addr,
1838                            long                   msgid,
1839                            struct kernel_ipmi_msg *msg,
1840                            struct ipmi_smi_msg    *smi_msg,
1841                            struct ipmi_recv_msg   *recv_msg,
1842                            unsigned char          source_address,
1843                            unsigned char          source_lun,
1844                            int                    retries,
1845                            unsigned int           retry_time_ms)
1846 {
1847         struct ipmi_ipmb_addr *ipmb_addr;
1848         unsigned char ipmb_seq;
1849         long seqid;
1850         int broadcast = 0;
1851         struct ipmi_channel *chans;
1852         int rv = 0;
1853
1854         if (addr->channel >= IPMI_MAX_CHANNELS) {
1855                 ipmi_inc_stat(intf, sent_invalid_commands);
1856                 return -EINVAL;
1857         }
1858
1859         chans = READ_ONCE(intf->channel_list)->c;
1860
1861         if (chans[addr->channel].medium != IPMI_CHANNEL_MEDIUM_IPMB) {
1862                 ipmi_inc_stat(intf, sent_invalid_commands);
1863                 return -EINVAL;
1864         }
1865
1866         if (addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE) {
1867                 /*
1868                  * Broadcasts add a zero at the beginning of the
1869                  * message, but otherwise is the same as an IPMB
1870                  * address.
1871                  */
1872                 addr->addr_type = IPMI_IPMB_ADDR_TYPE;
1873                 broadcast = 1;
1874                 retries = 0; /* Don't retry broadcasts. */
1875         }
1876
1877         /*
1878          * 9 for the header and 1 for the checksum, plus
1879          * possibly one for the broadcast.
1880          */
1881         if ((msg->data_len + 10 + broadcast) > IPMI_MAX_MSG_LENGTH) {
1882                 ipmi_inc_stat(intf, sent_invalid_commands);
1883                 return -EMSGSIZE;
1884         }
1885
1886         ipmb_addr = (struct ipmi_ipmb_addr *) addr;
1887         if (ipmb_addr->lun > 3) {
1888                 ipmi_inc_stat(intf, sent_invalid_commands);
1889                 return -EINVAL;
1890         }
1891
1892         memcpy(&recv_msg->addr, ipmb_addr, sizeof(*ipmb_addr));
1893
1894         if (recv_msg->msg.netfn & 0x1) {
1895                 /*
1896                  * It's a response, so use the user's sequence
1897                  * from msgid.
1898                  */
1899                 ipmi_inc_stat(intf, sent_ipmb_responses);
1900                 format_ipmb_msg(smi_msg, msg, ipmb_addr, msgid,
1901                                 msgid, broadcast,
1902                                 source_address, source_lun);
1903
1904                 /*
1905                  * Save the receive message so we can use it
1906                  * to deliver the response.
1907                  */
1908                 smi_msg->user_data = recv_msg;
1909         } else {
1910                 /* It's a command, so get a sequence for it. */
1911                 unsigned long flags;
1912
1913                 spin_lock_irqsave(&intf->seq_lock, flags);
1914
1915                 if (is_maintenance_mode_cmd(msg))
1916                         intf->ipmb_maintenance_mode_timeout =
1917                                 maintenance_mode_timeout_ms;
1918
1919                 if (intf->ipmb_maintenance_mode_timeout && retry_time_ms == 0)
1920                         /* Different default in maintenance mode */
1921                         retry_time_ms = default_maintenance_retry_ms;
1922
1923                 /*
1924                  * Create a sequence number with a 1 second
1925                  * timeout and 4 retries.
1926                  */
1927                 rv = intf_next_seq(intf,
1928                                    recv_msg,
1929                                    retry_time_ms,
1930                                    retries,
1931                                    broadcast,
1932                                    &ipmb_seq,
1933                                    &seqid);
1934                 if (rv)
1935                         /*
1936                          * We have used up all the sequence numbers,
1937                          * probably, so abort.
1938                          */
1939                         goto out_err;
1940
1941                 ipmi_inc_stat(intf, sent_ipmb_commands);
1942
1943                 /*
1944                  * Store the sequence number in the message,
1945                  * so that when the send message response
1946                  * comes back we can start the timer.
1947                  */
1948                 format_ipmb_msg(smi_msg, msg, ipmb_addr,
1949                                 STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
1950                                 ipmb_seq, broadcast,
1951                                 source_address, source_lun);
1952
1953                 /*
1954                  * Copy the message into the recv message data, so we
1955                  * can retransmit it later if necessary.
1956                  */
1957                 memcpy(recv_msg->msg_data, smi_msg->data,
1958                        smi_msg->data_size);
1959                 recv_msg->msg.data = recv_msg->msg_data;
1960                 recv_msg->msg.data_len = smi_msg->data_size;
1961
1962                 /*
1963                  * We don't unlock until here, because we need
1964                  * to copy the completed message into the
1965                  * recv_msg before we release the lock.
1966                  * Otherwise, race conditions may bite us.  I
1967                  * know that's pretty paranoid, but I prefer
1968                  * to be correct.
1969                  */
1970 out_err:
1971                 spin_unlock_irqrestore(&intf->seq_lock, flags);
1972         }
1973
1974         return rv;
1975 }
1976
1977 static int i_ipmi_req_lan(struct ipmi_smi        *intf,
1978                           struct ipmi_addr       *addr,
1979                           long                   msgid,
1980                           struct kernel_ipmi_msg *msg,
1981                           struct ipmi_smi_msg    *smi_msg,
1982                           struct ipmi_recv_msg   *recv_msg,
1983                           unsigned char          source_lun,
1984                           int                    retries,
1985                           unsigned int           retry_time_ms)
1986 {
1987         struct ipmi_lan_addr  *lan_addr;
1988         unsigned char ipmb_seq;
1989         long seqid;
1990         struct ipmi_channel *chans;
1991         int rv = 0;
1992
1993         if (addr->channel >= IPMI_MAX_CHANNELS) {
1994                 ipmi_inc_stat(intf, sent_invalid_commands);
1995                 return -EINVAL;
1996         }
1997
1998         chans = READ_ONCE(intf->channel_list)->c;
1999
2000         if ((chans[addr->channel].medium
2001                                 != IPMI_CHANNEL_MEDIUM_8023LAN)
2002                         && (chans[addr->channel].medium
2003                             != IPMI_CHANNEL_MEDIUM_ASYNC)) {
2004                 ipmi_inc_stat(intf, sent_invalid_commands);
2005                 return -EINVAL;
2006         }
2007
2008         /* 11 for the header and 1 for the checksum. */
2009         if ((msg->data_len + 12) > IPMI_MAX_MSG_LENGTH) {
2010                 ipmi_inc_stat(intf, sent_invalid_commands);
2011                 return -EMSGSIZE;
2012         }
2013
2014         lan_addr = (struct ipmi_lan_addr *) addr;
2015         if (lan_addr->lun > 3) {
2016                 ipmi_inc_stat(intf, sent_invalid_commands);
2017                 return -EINVAL;
2018         }
2019
2020         memcpy(&recv_msg->addr, lan_addr, sizeof(*lan_addr));
2021
2022         if (recv_msg->msg.netfn & 0x1) {
2023                 /*
2024                  * It's a response, so use the user's sequence
2025                  * from msgid.
2026                  */
2027                 ipmi_inc_stat(intf, sent_lan_responses);
2028                 format_lan_msg(smi_msg, msg, lan_addr, msgid,
2029                                msgid, source_lun);
2030
2031                 /*
2032                  * Save the receive message so we can use it
2033                  * to deliver the response.
2034                  */
2035                 smi_msg->user_data = recv_msg;
2036         } else {
2037                 /* It's a command, so get a sequence for it. */
2038                 unsigned long flags;
2039
2040                 spin_lock_irqsave(&intf->seq_lock, flags);
2041
2042                 /*
2043                  * Create a sequence number with a 1 second
2044                  * timeout and 4 retries.
2045                  */
2046                 rv = intf_next_seq(intf,
2047                                    recv_msg,
2048                                    retry_time_ms,
2049                                    retries,
2050                                    0,
2051                                    &ipmb_seq,
2052                                    &seqid);
2053                 if (rv)
2054                         /*
2055                          * We have used up all the sequence numbers,
2056                          * probably, so abort.
2057                          */
2058                         goto out_err;
2059
2060                 ipmi_inc_stat(intf, sent_lan_commands);
2061
2062                 /*
2063                  * Store the sequence number in the message,
2064                  * so that when the send message response
2065                  * comes back we can start the timer.
2066                  */
2067                 format_lan_msg(smi_msg, msg, lan_addr,
2068                                STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
2069                                ipmb_seq, source_lun);
2070
2071                 /*
2072                  * Copy the message into the recv message data, so we
2073                  * can retransmit it later if necessary.
2074                  */
2075                 memcpy(recv_msg->msg_data, smi_msg->data,
2076                        smi_msg->data_size);
2077                 recv_msg->msg.data = recv_msg->msg_data;
2078                 recv_msg->msg.data_len = smi_msg->data_size;
2079
2080                 /*
2081                  * We don't unlock until here, because we need
2082                  * to copy the completed message into the
2083                  * recv_msg before we release the lock.
2084                  * Otherwise, race conditions may bite us.  I
2085                  * know that's pretty paranoid, but I prefer
2086                  * to be correct.
2087                  */
2088 out_err:
2089                 spin_unlock_irqrestore(&intf->seq_lock, flags);
2090         }
2091
2092         return rv;
2093 }
2094
2095 /*
2096  * Separate from ipmi_request so that the user does not have to be
2097  * supplied in certain circumstances (mainly at panic time).  If
2098  * messages are supplied, they will be freed, even if an error
2099  * occurs.
2100  */
2101 static int i_ipmi_request(struct ipmi_user     *user,
2102                           struct ipmi_smi      *intf,
2103                           struct ipmi_addr     *addr,
2104                           long                 msgid,
2105                           struct kernel_ipmi_msg *msg,
2106                           void                 *user_msg_data,
2107                           void                 *supplied_smi,
2108                           struct ipmi_recv_msg *supplied_recv,
2109                           int                  priority,
2110                           unsigned char        source_address,
2111                           unsigned char        source_lun,
2112                           int                  retries,
2113                           unsigned int         retry_time_ms)
2114 {
2115         struct ipmi_smi_msg *smi_msg;
2116         struct ipmi_recv_msg *recv_msg;
2117         int rv = 0;
2118
2119         if (supplied_recv)
2120                 recv_msg = supplied_recv;
2121         else {
2122                 recv_msg = ipmi_alloc_recv_msg();
2123                 if (recv_msg == NULL) {
2124                         rv = -ENOMEM;
2125                         goto out;
2126                 }
2127         }
2128         recv_msg->user_msg_data = user_msg_data;
2129
2130         if (supplied_smi)
2131                 smi_msg = (struct ipmi_smi_msg *) supplied_smi;
2132         else {
2133                 smi_msg = ipmi_alloc_smi_msg();
2134                 if (smi_msg == NULL) {
2135                         ipmi_free_recv_msg(recv_msg);
2136                         rv = -ENOMEM;
2137                         goto out;
2138                 }
2139         }
2140
2141         rcu_read_lock();
2142         if (intf->in_shutdown) {
2143                 rv = -ENODEV;
2144                 goto out_err;
2145         }
2146
2147         recv_msg->user = user;
2148         if (user)
2149                 /* The put happens when the message is freed. */
2150                 kref_get(&user->refcount);
2151         recv_msg->msgid = msgid;
2152         /*
2153          * Store the message to send in the receive message so timeout
2154          * responses can get the proper response data.
2155          */
2156         recv_msg->msg = *msg;
2157
2158         if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
2159                 rv = i_ipmi_req_sysintf(intf, addr, msgid, msg, smi_msg,
2160                                         recv_msg, retries, retry_time_ms);
2161         } else if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
2162                 rv = i_ipmi_req_ipmb(intf, addr, msgid, msg, smi_msg, recv_msg,
2163                                      source_address, source_lun,
2164                                      retries, retry_time_ms);
2165         } else if (is_lan_addr(addr)) {
2166                 rv = i_ipmi_req_lan(intf, addr, msgid, msg, smi_msg, recv_msg,
2167                                     source_lun, retries, retry_time_ms);
2168         } else {
2169             /* Unknown address type. */
2170                 ipmi_inc_stat(intf, sent_invalid_commands);
2171                 rv = -EINVAL;
2172         }
2173
2174         if (rv) {
2175 out_err:
2176                 ipmi_free_smi_msg(smi_msg);
2177                 ipmi_free_recv_msg(recv_msg);
2178         } else {
2179                 ipmi_debug_msg("Send", smi_msg->data, smi_msg->data_size);
2180
2181                 smi_send(intf, intf->handlers, smi_msg, priority);
2182         }
2183         rcu_read_unlock();
2184
2185 out:
2186         return rv;
2187 }
2188
2189 static int check_addr(struct ipmi_smi  *intf,
2190                       struct ipmi_addr *addr,
2191                       unsigned char    *saddr,
2192                       unsigned char    *lun)
2193 {
2194         if (addr->channel >= IPMI_MAX_CHANNELS)
2195                 return -EINVAL;
2196         addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS);
2197         *lun = intf->addrinfo[addr->channel].lun;
2198         *saddr = intf->addrinfo[addr->channel].address;
2199         return 0;
2200 }
2201
2202 int ipmi_request_settime(struct ipmi_user *user,
2203                          struct ipmi_addr *addr,
2204                          long             msgid,
2205                          struct kernel_ipmi_msg  *msg,
2206                          void             *user_msg_data,
2207                          int              priority,
2208                          int              retries,
2209                          unsigned int     retry_time_ms)
2210 {
2211         unsigned char saddr = 0, lun = 0;
2212         int rv, index;
2213
2214         if (!user)
2215                 return -EINVAL;
2216
2217         user = acquire_ipmi_user(user, &index);
2218         if (!user)
2219                 return -ENODEV;
2220
2221         rv = check_addr(user->intf, addr, &saddr, &lun);
2222         if (!rv)
2223                 rv = i_ipmi_request(user,
2224                                     user->intf,
2225                                     addr,
2226                                     msgid,
2227                                     msg,
2228                                     user_msg_data,
2229                                     NULL, NULL,
2230                                     priority,
2231                                     saddr,
2232                                     lun,
2233                                     retries,
2234                                     retry_time_ms);
2235
2236         release_ipmi_user(user, index);
2237         return rv;
2238 }
2239 EXPORT_SYMBOL(ipmi_request_settime);
2240
2241 int ipmi_request_supply_msgs(struct ipmi_user     *user,
2242                              struct ipmi_addr     *addr,
2243                              long                 msgid,
2244                              struct kernel_ipmi_msg *msg,
2245                              void                 *user_msg_data,
2246                              void                 *supplied_smi,
2247                              struct ipmi_recv_msg *supplied_recv,
2248                              int                  priority)
2249 {
2250         unsigned char saddr = 0, lun = 0;
2251         int rv, index;
2252
2253         if (!user)
2254                 return -EINVAL;
2255
2256         user = acquire_ipmi_user(user, &index);
2257         if (!user)
2258                 return -ENODEV;
2259
2260         rv = check_addr(user->intf, addr, &saddr, &lun);
2261         if (!rv)
2262                 rv = i_ipmi_request(user,
2263                                     user->intf,
2264                                     addr,
2265                                     msgid,
2266                                     msg,
2267                                     user_msg_data,
2268                                     supplied_smi,
2269                                     supplied_recv,
2270                                     priority,
2271                                     saddr,
2272                                     lun,
2273                                     -1, 0);
2274
2275         release_ipmi_user(user, index);
2276         return rv;
2277 }
2278 EXPORT_SYMBOL(ipmi_request_supply_msgs);
2279
2280 static void bmc_device_id_handler(struct ipmi_smi *intf,
2281                                   struct ipmi_recv_msg *msg)
2282 {
2283         int rv;
2284
2285         if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
2286                         || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
2287                         || (msg->msg.cmd != IPMI_GET_DEVICE_ID_CMD)) {
2288                 dev_warn(intf->si_dev,
2289                          "invalid device_id msg: addr_type=%d netfn=%x cmd=%x\n",
2290                          msg->addr.addr_type, msg->msg.netfn, msg->msg.cmd);
2291                 return;
2292         }
2293
2294         rv = ipmi_demangle_device_id(msg->msg.netfn, msg->msg.cmd,
2295                         msg->msg.data, msg->msg.data_len, &intf->bmc->fetch_id);
2296         if (rv) {
2297                 dev_warn(intf->si_dev, "device id demangle failed: %d\n", rv);
2298                 intf->bmc->dyn_id_set = 0;
2299         } else {
2300                 /*
2301                  * Make sure the id data is available before setting
2302                  * dyn_id_set.
2303                  */
2304                 smp_wmb();
2305                 intf->bmc->dyn_id_set = 1;
2306         }
2307
2308         wake_up(&intf->waitq);
2309 }
2310
2311 static int
2312 send_get_device_id_cmd(struct ipmi_smi *intf)
2313 {
2314         struct ipmi_system_interface_addr si;
2315         struct kernel_ipmi_msg msg;
2316
2317         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
2318         si.channel = IPMI_BMC_CHANNEL;
2319         si.lun = 0;
2320
2321         msg.netfn = IPMI_NETFN_APP_REQUEST;
2322         msg.cmd = IPMI_GET_DEVICE_ID_CMD;
2323         msg.data = NULL;
2324         msg.data_len = 0;
2325
2326         return i_ipmi_request(NULL,
2327                               intf,
2328                               (struct ipmi_addr *) &si,
2329                               0,
2330                               &msg,
2331                               intf,
2332                               NULL,
2333                               NULL,
2334                               0,
2335                               intf->addrinfo[0].address,
2336                               intf->addrinfo[0].lun,
2337                               -1, 0);
2338 }
2339
2340 static int __get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc)
2341 {
2342         int rv;
2343
2344         bmc->dyn_id_set = 2;
2345
2346         intf->null_user_handler = bmc_device_id_handler;
2347
2348         rv = send_get_device_id_cmd(intf);
2349         if (rv)
2350                 return rv;
2351
2352         wait_event(intf->waitq, bmc->dyn_id_set != 2);
2353
2354         if (!bmc->dyn_id_set)
2355                 rv = -EIO; /* Something went wrong in the fetch. */
2356
2357         /* dyn_id_set makes the id data available. */
2358         smp_rmb();
2359
2360         intf->null_user_handler = NULL;
2361
2362         return rv;
2363 }
2364
2365 /*
2366  * Fetch the device id for the bmc/interface.  You must pass in either
2367  * bmc or intf, this code will get the other one.  If the data has
2368  * been recently fetched, this will just use the cached data.  Otherwise
2369  * it will run a new fetch.
2370  *
2371  * Except for the first time this is called (in ipmi_register_smi()),
2372  * this will always return good data;
2373  */
2374 static int __bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2375                                struct ipmi_device_id *id,
2376                                bool *guid_set, guid_t *guid, int intf_num)
2377 {
2378         int rv = 0;
2379         int prev_dyn_id_set, prev_guid_set;
2380         bool intf_set = intf != NULL;
2381
2382         if (!intf) {
2383                 mutex_lock(&bmc->dyn_mutex);
2384 retry_bmc_lock:
2385                 if (list_empty(&bmc->intfs)) {
2386                         mutex_unlock(&bmc->dyn_mutex);
2387                         return -ENOENT;
2388                 }
2389                 intf = list_first_entry(&bmc->intfs, struct ipmi_smi,
2390                                         bmc_link);
2391                 kref_get(&intf->refcount);
2392                 mutex_unlock(&bmc->dyn_mutex);
2393                 mutex_lock(&intf->bmc_reg_mutex);
2394                 mutex_lock(&bmc->dyn_mutex);
2395                 if (intf != list_first_entry(&bmc->intfs, struct ipmi_smi,
2396                                              bmc_link)) {
2397                         mutex_unlock(&intf->bmc_reg_mutex);
2398                         kref_put(&intf->refcount, intf_free);
2399                         goto retry_bmc_lock;
2400                 }
2401         } else {
2402                 mutex_lock(&intf->bmc_reg_mutex);
2403                 bmc = intf->bmc;
2404                 mutex_lock(&bmc->dyn_mutex);
2405                 kref_get(&intf->refcount);
2406         }
2407
2408         /* If we have a valid and current ID, just return that. */
2409         if (intf->in_bmc_register ||
2410             (bmc->dyn_id_set && time_is_after_jiffies(bmc->dyn_id_expiry)))
2411                 goto out_noprocessing;
2412
2413         prev_guid_set = bmc->dyn_guid_set;
2414         __get_guid(intf);
2415
2416         prev_dyn_id_set = bmc->dyn_id_set;
2417         rv = __get_device_id(intf, bmc);
2418         if (rv)
2419                 goto out;
2420
2421         /*
2422          * The guid, device id, manufacturer id, and product id should
2423          * not change on a BMC.  If it does we have to do some dancing.
2424          */
2425         if (!intf->bmc_registered
2426             || (!prev_guid_set && bmc->dyn_guid_set)
2427             || (!prev_dyn_id_set && bmc->dyn_id_set)
2428             || (prev_guid_set && bmc->dyn_guid_set
2429                 && !guid_equal(&bmc->guid, &bmc->fetch_guid))
2430             || bmc->id.device_id != bmc->fetch_id.device_id
2431             || bmc->id.manufacturer_id != bmc->fetch_id.manufacturer_id
2432             || bmc->id.product_id != bmc->fetch_id.product_id) {
2433                 struct ipmi_device_id id = bmc->fetch_id;
2434                 int guid_set = bmc->dyn_guid_set;
2435                 guid_t guid;
2436
2437                 guid = bmc->fetch_guid;
2438                 mutex_unlock(&bmc->dyn_mutex);
2439
2440                 __ipmi_bmc_unregister(intf);
2441                 /* Fill in the temporary BMC for good measure. */
2442                 intf->bmc->id = id;
2443                 intf->bmc->dyn_guid_set = guid_set;
2444                 intf->bmc->guid = guid;
2445                 if (__ipmi_bmc_register(intf, &id, guid_set, &guid, intf_num))
2446                         need_waiter(intf); /* Retry later on an error. */
2447                 else
2448                         __scan_channels(intf, &id);
2449
2450
2451                 if (!intf_set) {
2452                         /*
2453                          * We weren't given the interface on the
2454                          * command line, so restart the operation on
2455                          * the next interface for the BMC.
2456                          */
2457                         mutex_unlock(&intf->bmc_reg_mutex);
2458                         mutex_lock(&bmc->dyn_mutex);
2459                         goto retry_bmc_lock;
2460                 }
2461
2462                 /* We have a new BMC, set it up. */
2463                 bmc = intf->bmc;
2464                 mutex_lock(&bmc->dyn_mutex);
2465                 goto out_noprocessing;
2466         } else if (memcmp(&bmc->fetch_id, &bmc->id, sizeof(bmc->id)))
2467                 /* Version info changes, scan the channels again. */
2468                 __scan_channels(intf, &bmc->fetch_id);
2469
2470         bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
2471
2472 out:
2473         if (rv && prev_dyn_id_set) {
2474                 rv = 0; /* Ignore failures if we have previous data. */
2475                 bmc->dyn_id_set = prev_dyn_id_set;
2476         }
2477         if (!rv) {
2478                 bmc->id = bmc->fetch_id;
2479                 if (bmc->dyn_guid_set)
2480                         bmc->guid = bmc->fetch_guid;
2481                 else if (prev_guid_set)
2482                         /*
2483                          * The guid used to be valid and it failed to fetch,
2484                          * just use the cached value.
2485                          */
2486                         bmc->dyn_guid_set = prev_guid_set;
2487         }
2488 out_noprocessing:
2489         if (!rv) {
2490                 if (id)
2491                         *id = bmc->id;
2492
2493                 if (guid_set)
2494                         *guid_set = bmc->dyn_guid_set;
2495
2496                 if (guid && bmc->dyn_guid_set)
2497                         *guid =  bmc->guid;
2498         }
2499
2500         mutex_unlock(&bmc->dyn_mutex);
2501         mutex_unlock(&intf->bmc_reg_mutex);
2502
2503         kref_put(&intf->refcount, intf_free);
2504         return rv;
2505 }
2506
2507 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2508                              struct ipmi_device_id *id,
2509                              bool *guid_set, guid_t *guid)
2510 {
2511         return __bmc_get_device_id(intf, bmc, id, guid_set, guid, -1);
2512 }
2513
2514 static ssize_t device_id_show(struct device *dev,
2515                               struct device_attribute *attr,
2516                               char *buf)
2517 {
2518         struct bmc_device *bmc = to_bmc_device(dev);
2519         struct ipmi_device_id id;
2520         int rv;
2521
2522         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2523         if (rv)
2524                 return rv;
2525
2526         return snprintf(buf, 10, "%u\n", id.device_id);
2527 }
2528 static DEVICE_ATTR_RO(device_id);
2529
2530 static ssize_t provides_device_sdrs_show(struct device *dev,
2531                                          struct device_attribute *attr,
2532                                          char *buf)
2533 {
2534         struct bmc_device *bmc = to_bmc_device(dev);
2535         struct ipmi_device_id id;
2536         int rv;
2537
2538         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2539         if (rv)
2540                 return rv;
2541
2542         return snprintf(buf, 10, "%u\n", (id.device_revision & 0x80) >> 7);
2543 }
2544 static DEVICE_ATTR_RO(provides_device_sdrs);
2545
2546 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
2547                              char *buf)
2548 {
2549         struct bmc_device *bmc = to_bmc_device(dev);
2550         struct ipmi_device_id id;
2551         int rv;
2552
2553         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2554         if (rv)
2555                 return rv;
2556
2557         return snprintf(buf, 20, "%u\n", id.device_revision & 0x0F);
2558 }
2559 static DEVICE_ATTR_RO(revision);
2560
2561 static ssize_t firmware_revision_show(struct device *dev,
2562                                       struct device_attribute *attr,
2563                                       char *buf)
2564 {
2565         struct bmc_device *bmc = to_bmc_device(dev);
2566         struct ipmi_device_id id;
2567         int rv;
2568
2569         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2570         if (rv)
2571                 return rv;
2572
2573         return snprintf(buf, 20, "%u.%x\n", id.firmware_revision_1,
2574                         id.firmware_revision_2);
2575 }
2576 static DEVICE_ATTR_RO(firmware_revision);
2577
2578 static ssize_t ipmi_version_show(struct device *dev,
2579                                  struct device_attribute *attr,
2580                                  char *buf)
2581 {
2582         struct bmc_device *bmc = to_bmc_device(dev);
2583         struct ipmi_device_id id;
2584         int rv;
2585
2586         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2587         if (rv)
2588                 return rv;
2589
2590         return snprintf(buf, 20, "%u.%u\n",
2591                         ipmi_version_major(&id),
2592                         ipmi_version_minor(&id));
2593 }
2594 static DEVICE_ATTR_RO(ipmi_version);
2595
2596 static ssize_t add_dev_support_show(struct device *dev,
2597                                     struct device_attribute *attr,
2598                                     char *buf)
2599 {
2600         struct bmc_device *bmc = to_bmc_device(dev);
2601         struct ipmi_device_id id;
2602         int rv;
2603
2604         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2605         if (rv)
2606                 return rv;
2607
2608         return snprintf(buf, 10, "0x%02x\n", id.additional_device_support);
2609 }
2610 static DEVICE_ATTR(additional_device_support, S_IRUGO, add_dev_support_show,
2611                    NULL);
2612
2613 static ssize_t manufacturer_id_show(struct device *dev,
2614                                     struct device_attribute *attr,
2615                                     char *buf)
2616 {
2617         struct bmc_device *bmc = to_bmc_device(dev);
2618         struct ipmi_device_id id;
2619         int rv;
2620
2621         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2622         if (rv)
2623                 return rv;
2624
2625         return snprintf(buf, 20, "0x%6.6x\n", id.manufacturer_id);
2626 }
2627 static DEVICE_ATTR_RO(manufacturer_id);
2628
2629 static ssize_t product_id_show(struct device *dev,
2630                                struct device_attribute *attr,
2631                                char *buf)
2632 {
2633         struct bmc_device *bmc = to_bmc_device(dev);
2634         struct ipmi_device_id id;
2635         int rv;
2636
2637         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2638         if (rv)
2639                 return rv;
2640
2641         return snprintf(buf, 10, "0x%4.4x\n", id.product_id);
2642 }
2643 static DEVICE_ATTR_RO(product_id);
2644
2645 static ssize_t aux_firmware_rev_show(struct device *dev,
2646                                      struct device_attribute *attr,
2647                                      char *buf)
2648 {
2649         struct bmc_device *bmc = to_bmc_device(dev);
2650         struct ipmi_device_id id;
2651         int rv;
2652
2653         rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2654         if (rv)
2655                 return rv;
2656
2657         return snprintf(buf, 21, "0x%02x 0x%02x 0x%02x 0x%02x\n",
2658                         id.aux_firmware_revision[3],
2659                         id.aux_firmware_revision[2],
2660                         id.aux_firmware_revision[1],
2661                         id.aux_firmware_revision[0]);
2662 }
2663 static DEVICE_ATTR(aux_firmware_revision, S_IRUGO, aux_firmware_rev_show, NULL);
2664
2665 static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
2666                          char *buf)
2667 {
2668         struct bmc_device *bmc = to_bmc_device(dev);
2669         bool guid_set;
2670         guid_t guid;
2671         int rv;
2672
2673         rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, &guid);
2674         if (rv)
2675                 return rv;
2676         if (!guid_set)
2677                 return -ENOENT;
2678
2679         return snprintf(buf, 38, "%pUl\n", guid.b);
2680 }
2681 static DEVICE_ATTR_RO(guid);
2682
2683 static struct attribute *bmc_dev_attrs[] = {
2684         &dev_attr_device_id.attr,
2685         &dev_attr_provides_device_sdrs.attr,
2686         &dev_attr_revision.attr,
2687         &dev_attr_firmware_revision.attr,
2688         &dev_attr_ipmi_version.attr,
2689         &dev_attr_additional_device_support.attr,
2690         &dev_attr_manufacturer_id.attr,
2691         &dev_attr_product_id.attr,
2692         &dev_attr_aux_firmware_revision.attr,
2693         &dev_attr_guid.attr,
2694         NULL
2695 };
2696
2697 static umode_t bmc_dev_attr_is_visible(struct kobject *kobj,
2698                                        struct attribute *attr, int idx)
2699 {
2700         struct device *dev = kobj_to_dev(kobj);
2701         struct bmc_device *bmc = to_bmc_device(dev);
2702         umode_t mode = attr->mode;
2703         int rv;
2704
2705         if (attr == &dev_attr_aux_firmware_revision.attr) {
2706                 struct ipmi_device_id id;
2707
2708                 rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2709                 return (!rv && id.aux_firmware_revision_set) ? mode : 0;
2710         }
2711         if (attr == &dev_attr_guid.attr) {
2712                 bool guid_set;
2713
2714                 rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, NULL);
2715                 return (!rv && guid_set) ? mode : 0;
2716         }
2717         return mode;
2718 }
2719
2720 static const struct attribute_group bmc_dev_attr_group = {
2721         .attrs          = bmc_dev_attrs,
2722         .is_visible     = bmc_dev_attr_is_visible,
2723 };
2724
2725 static const struct attribute_group *bmc_dev_attr_groups[] = {
2726         &bmc_dev_attr_group,
2727         NULL
2728 };
2729
2730 static const struct device_type bmc_device_type = {
2731         .groups         = bmc_dev_attr_groups,
2732 };
2733
2734 static int __find_bmc_guid(struct device *dev, void *data)
2735 {
2736         guid_t *guid = data;
2737         struct bmc_device *bmc;
2738         int rv;
2739
2740         if (dev->type != &bmc_device_type)
2741                 return 0;
2742
2743         bmc = to_bmc_device(dev);
2744         rv = bmc->dyn_guid_set && guid_equal(&bmc->guid, guid);
2745         if (rv)
2746                 rv = kref_get_unless_zero(&bmc->usecount);
2747         return rv;
2748 }
2749
2750 /*
2751  * Returns with the bmc's usecount incremented, if it is non-NULL.
2752  */
2753 static struct bmc_device *ipmi_find_bmc_guid(struct device_driver *drv,
2754                                              guid_t *guid)
2755 {
2756         struct device *dev;
2757         struct bmc_device *bmc = NULL;
2758
2759         dev = driver_find_device(drv, NULL, guid, __find_bmc_guid);
2760         if (dev) {
2761                 bmc = to_bmc_device(dev);
2762                 put_device(dev);
2763         }
2764         return bmc;
2765 }
2766
2767 struct prod_dev_id {
2768         unsigned int  product_id;
2769         unsigned char device_id;
2770 };
2771
2772 static int __find_bmc_prod_dev_id(struct device *dev, void *data)
2773 {
2774         struct prod_dev_id *cid = data;
2775         struct bmc_device *bmc;
2776         int rv;
2777
2778         if (dev->type != &bmc_device_type)
2779                 return 0;
2780
2781         bmc = to_bmc_device(dev);
2782         rv = (bmc->id.product_id == cid->product_id
2783               && bmc->id.device_id == cid->device_id);
2784         if (rv)
2785                 rv = kref_get_unless_zero(&bmc->usecount);
2786         return rv;
2787 }
2788
2789 /*
2790  * Returns with the bmc's usecount incremented, if it is non-NULL.
2791  */
2792 static struct bmc_device *ipmi_find_bmc_prod_dev_id(
2793         struct device_driver *drv,
2794         unsigned int product_id, unsigned char device_id)
2795 {
2796         struct prod_dev_id id = {
2797                 .product_id = product_id,
2798                 .device_id = device_id,
2799         };
2800         struct device *dev;
2801         struct bmc_device *bmc = NULL;
2802
2803         dev = driver_find_device(drv, NULL, &id, __find_bmc_prod_dev_id);
2804         if (dev) {
2805                 bmc = to_bmc_device(dev);
2806                 put_device(dev);
2807         }
2808         return bmc;
2809 }
2810
2811 static DEFINE_IDA(ipmi_bmc_ida);
2812
2813 static void
2814 release_bmc_device(struct device *dev)
2815 {
2816         kfree(to_bmc_device(dev));
2817 }
2818
2819 static void cleanup_bmc_work(struct work_struct *work)
2820 {
2821         struct bmc_device *bmc = container_of(work, struct bmc_device,
2822                                               remove_work);
2823         int id = bmc->pdev.id; /* Unregister overwrites id */
2824
2825         platform_device_unregister(&bmc->pdev);
2826         ida_simple_remove(&ipmi_bmc_ida, id);
2827 }
2828
2829 static void
2830 cleanup_bmc_device(struct kref *ref)
2831 {
2832         struct bmc_device *bmc = container_of(ref, struct bmc_device, usecount);
2833
2834         /*
2835          * Remove the platform device in a work queue to avoid issues
2836          * with removing the device attributes while reading a device
2837          * attribute.
2838          */
2839         schedule_work(&bmc->remove_work);
2840 }
2841
2842 /*
2843  * Must be called with intf->bmc_reg_mutex held.
2844  */
2845 static void __ipmi_bmc_unregister(struct ipmi_smi *intf)
2846 {
2847         struct bmc_device *bmc = intf->bmc;
2848
2849         if (!intf->bmc_registered)
2850                 return;
2851
2852         sysfs_remove_link(&intf->si_dev->kobj, "bmc");
2853         sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
2854         kfree(intf->my_dev_name);
2855         intf->my_dev_name = NULL;
2856
2857         mutex_lock(&bmc->dyn_mutex);
2858         list_del(&intf->bmc_link);
2859         mutex_unlock(&bmc->dyn_mutex);
2860         intf->bmc = &intf->tmp_bmc;
2861         kref_put(&bmc->usecount, cleanup_bmc_device);
2862         intf->bmc_registered = false;
2863 }
2864
2865 static void ipmi_bmc_unregister(struct ipmi_smi *intf)
2866 {
2867         mutex_lock(&intf->bmc_reg_mutex);
2868         __ipmi_bmc_unregister(intf);
2869         mutex_unlock(&intf->bmc_reg_mutex);
2870 }
2871
2872 /*
2873  * Must be called with intf->bmc_reg_mutex held.
2874  */
2875 static int __ipmi_bmc_register(struct ipmi_smi *intf,
2876                                struct ipmi_device_id *id,
2877                                bool guid_set, guid_t *guid, int intf_num)
2878 {
2879         int               rv;
2880         struct bmc_device *bmc;
2881         struct bmc_device *old_bmc;
2882
2883         /*
2884          * platform_device_register() can cause bmc_reg_mutex to
2885          * be claimed because of the is_visible functions of
2886          * the attributes.  Eliminate possible recursion and
2887          * release the lock.
2888          */
2889         intf->in_bmc_register = true;
2890         mutex_unlock(&intf->bmc_reg_mutex);
2891
2892         /*
2893          * Try to find if there is an bmc_device struct
2894          * representing the interfaced BMC already
2895          */
2896         mutex_lock(&ipmidriver_mutex);
2897         if (guid_set)
2898                 old_bmc = ipmi_find_bmc_guid(&ipmidriver.driver, guid);
2899         else
2900                 old_bmc = ipmi_find_bmc_prod_dev_id(&ipmidriver.driver,
2901                                                     id->product_id,
2902                                                     id->device_id);
2903
2904         /*
2905          * If there is already an bmc_device, free the new one,
2906          * otherwise register the new BMC device
2907          */
2908         if (old_bmc) {
2909                 bmc = old_bmc;
2910                 /*
2911                  * Note: old_bmc already has usecount incremented by
2912                  * the BMC find functions.
2913                  */
2914                 intf->bmc = old_bmc;
2915                 mutex_lock(&bmc->dyn_mutex);
2916                 list_add_tail(&intf->bmc_link, &bmc->intfs);
2917                 mutex_unlock(&bmc->dyn_mutex);
2918
2919                 dev_info(intf->si_dev,
2920                          "interfacing existing BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
2921                          bmc->id.manufacturer_id,
2922                          bmc->id.product_id,
2923                          bmc->id.device_id);
2924         } else {
2925                 bmc = kzalloc(sizeof(*bmc), GFP_KERNEL);
2926                 if (!bmc) {
2927                         rv = -ENOMEM;
2928                         goto out;
2929                 }
2930                 INIT_LIST_HEAD(&bmc->intfs);
2931                 mutex_init(&bmc->dyn_mutex);
2932                 INIT_WORK(&bmc->remove_work, cleanup_bmc_work);
2933
2934                 bmc->id = *id;
2935                 bmc->dyn_id_set = 1;
2936                 bmc->dyn_guid_set = guid_set;
2937                 bmc->guid = *guid;
2938                 bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
2939
2940                 bmc->pdev.name = "ipmi_bmc";
2941
2942                 rv = ida_simple_get(&ipmi_bmc_ida, 0, 0, GFP_KERNEL);
2943                 if (rv < 0)
2944                         goto out;
2945                 bmc->pdev.dev.driver = &ipmidriver.driver;
2946                 bmc->pdev.id = rv;
2947                 bmc->pdev.dev.release = release_bmc_device;
2948                 bmc->pdev.dev.type = &bmc_device_type;
2949                 kref_init(&bmc->usecount);
2950
2951                 intf->bmc = bmc;
2952                 mutex_lock(&bmc->dyn_mutex);
2953                 list_add_tail(&intf->bmc_link, &bmc->intfs);
2954                 mutex_unlock(&bmc->dyn_mutex);
2955
2956                 rv = platform_device_register(&bmc->pdev);
2957                 if (rv) {
2958                         dev_err(intf->si_dev,
2959                                 "Unable to register bmc device: %d\n",
2960                                 rv);
2961                         goto out_list_del;
2962                 }
2963
2964                 dev_info(intf->si_dev,
2965                          "Found new BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
2966                          bmc->id.manufacturer_id,
2967                          bmc->id.product_id,
2968                          bmc->id.device_id);
2969         }
2970
2971         /*
2972          * create symlink from system interface device to bmc device
2973          * and back.
2974          */
2975         rv = sysfs_create_link(&intf->si_dev->kobj, &bmc->pdev.dev.kobj, "bmc");
2976         if (rv) {
2977                 dev_err(intf->si_dev, "Unable to create bmc symlink: %d\n", rv);
2978                 goto out_put_bmc;
2979         }
2980
2981         if (intf_num == -1)
2982                 intf_num = intf->intf_num;
2983         intf->my_dev_name = kasprintf(GFP_KERNEL, "ipmi%d", intf_num);
2984         if (!intf->my_dev_name) {
2985                 rv = -ENOMEM;
2986                 dev_err(intf->si_dev, "Unable to allocate link from BMC: %d\n",
2987                         rv);
2988                 goto out_unlink1;
2989         }
2990
2991         rv = sysfs_create_link(&bmc->pdev.dev.kobj, &intf->si_dev->kobj,
2992                                intf->my_dev_name);
2993         if (rv) {
2994                 kfree(intf->my_dev_name);
2995                 intf->my_dev_name = NULL;
2996                 dev_err(intf->si_dev, "Unable to create symlink to bmc: %d\n",
2997                         rv);
2998                 goto out_free_my_dev_name;
2999         }
3000
3001         intf->bmc_registered = true;
3002
3003 out:
3004         mutex_unlock(&ipmidriver_mutex);
3005         mutex_lock(&intf->bmc_reg_mutex);
3006         intf->in_bmc_register = false;
3007         return rv;
3008
3009
3010 out_free_my_dev_name:
3011         kfree(intf->my_dev_name);
3012         intf->my_dev_name = NULL;
3013
3014 out_unlink1:
3015         sysfs_remove_link(&intf->si_dev->kobj, "bmc");
3016
3017 out_put_bmc:
3018         mutex_lock(&bmc->dyn_mutex);
3019         list_del(&intf->bmc_link);
3020         mutex_unlock(&bmc->dyn_mutex);
3021         intf->bmc = &intf->tmp_bmc;
3022         kref_put(&bmc->usecount, cleanup_bmc_device);
3023         goto out;
3024
3025 out_list_del:
3026         mutex_lock(&bmc->dyn_mutex);
3027         list_del(&intf->bmc_link);
3028         mutex_unlock(&bmc->dyn_mutex);
3029         intf->bmc = &intf->tmp_bmc;
3030         put_device(&bmc->pdev.dev);
3031         goto out;
3032 }
3033
3034 static int
3035 send_guid_cmd(struct ipmi_smi *intf, int chan)
3036 {
3037         struct kernel_ipmi_msg            msg;
3038         struct ipmi_system_interface_addr si;
3039
3040         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3041         si.channel = IPMI_BMC_CHANNEL;
3042         si.lun = 0;
3043
3044         msg.netfn = IPMI_NETFN_APP_REQUEST;
3045         msg.cmd = IPMI_GET_DEVICE_GUID_CMD;
3046         msg.data = NULL;
3047         msg.data_len = 0;
3048         return i_ipmi_request(NULL,
3049                               intf,
3050                               (struct ipmi_addr *) &si,
3051                               0,
3052                               &msg,
3053                               intf,
3054                               NULL,
3055                               NULL,
3056                               0,
3057                               intf->addrinfo[0].address,
3058                               intf->addrinfo[0].lun,
3059                               -1, 0);
3060 }
3061
3062 static void guid_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3063 {
3064         struct bmc_device *bmc = intf->bmc;
3065
3066         if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3067             || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
3068             || (msg->msg.cmd != IPMI_GET_DEVICE_GUID_CMD))
3069                 /* Not for me */
3070                 return;
3071
3072         if (msg->msg.data[0] != 0) {
3073                 /* Error from getting the GUID, the BMC doesn't have one. */
3074                 bmc->dyn_guid_set = 0;
3075                 goto out;
3076         }
3077
3078         if (msg->msg.data_len < 17) {
3079                 bmc->dyn_guid_set = 0;
3080                 dev_warn(intf->si_dev,
3081                          "The GUID response from the BMC was too short, it was %d but should have been 17.  Assuming GUID is not available.\n",
3082                          msg->msg.data_len);
3083                 goto out;
3084         }
3085
3086         memcpy(bmc->fetch_guid.b, msg->msg.data + 1, 16);
3087         /*
3088          * Make sure the guid data is available before setting
3089          * dyn_guid_set.
3090          */
3091         smp_wmb();
3092         bmc->dyn_guid_set = 1;
3093  out:
3094         wake_up(&intf->waitq);
3095 }
3096
3097 static void __get_guid(struct ipmi_smi *intf)
3098 {
3099         int rv;
3100         struct bmc_device *bmc = intf->bmc;
3101
3102         bmc->dyn_guid_set = 2;
3103         intf->null_user_handler = guid_handler;
3104         rv = send_guid_cmd(intf, 0);
3105         if (rv)
3106                 /* Send failed, no GUID available. */
3107                 bmc->dyn_guid_set = 0;
3108
3109         wait_event(intf->waitq, bmc->dyn_guid_set != 2);
3110
3111         /* dyn_guid_set makes the guid data available. */
3112         smp_rmb();
3113
3114         intf->null_user_handler = NULL;
3115 }
3116
3117 static int
3118 send_channel_info_cmd(struct ipmi_smi *intf, int chan)
3119 {
3120         struct kernel_ipmi_msg            msg;
3121         unsigned char                     data[1];
3122         struct ipmi_system_interface_addr si;
3123
3124         si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3125         si.channel = IPMI_BMC_CHANNEL;
3126         si.lun = 0;
3127
3128         msg.netfn = IPMI_NETFN_APP_REQUEST;
3129         msg.cmd = IPMI_GET_CHANNEL_INFO_CMD;
3130         msg.data = data;
3131         msg.data_len = 1;
3132         data[0] = chan;
3133         return i_ipmi_request(NULL,
3134                               intf,
3135                               (struct ipmi_addr *) &si,
3136                               0,
3137                               &msg,
3138                               intf,
3139                               NULL,
3140                               NULL,
3141                               0,
3142                               intf->addrinfo[0].address,
3143                               intf->addrinfo[0].lun,
3144                               -1, 0);
3145 }
3146
3147 static void
3148 channel_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3149 {
3150         int rv = 0;
3151         int ch;
3152         unsigned int set = intf->curr_working_cset;
3153         struct ipmi_channel *chans;
3154
3155         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3156             && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
3157             && (msg->msg.cmd == IPMI_GET_CHANNEL_INFO_CMD)) {
3158                 /* It's the one we want */
3159                 if (msg->msg.data[0] != 0) {
3160                         /* Got an error from the channel, just go on. */
3161
3162                         if (msg->msg.data[0] == IPMI_INVALID_COMMAND_ERR) {
3163                                 /*
3164                                  * If the MC does not support this
3165                                  * command, that is legal.  We just
3166                                  * assume it has one IPMB at channel
3167                                  * zero.
3168                                  */
3169                                 intf->wchannels[set].c[0].medium
3170                                         = IPMI_CHANNEL_MEDIUM_IPMB;
3171                                 intf->wchannels[set].c[0].protocol
3172                                         = IPMI_CHANNEL_PROTOCOL_IPMB;
3173
3174                                 intf->channel_list = intf->wchannels + set;
3175                                 intf->channels_ready = true;
3176                                 wake_up(&intf->waitq);
3177                                 goto out;
3178                         }
3179                         goto next_channel;
3180                 }
3181                 if (msg->msg.data_len < 4) {
3182                         /* Message not big enough, just go on. */
3183                         goto next_channel;
3184                 }
3185                 ch = intf->curr_channel;
3186                 chans = intf->wchannels[set].c;
3187                 chans[ch].medium = msg->msg.data[2] & 0x7f;
3188                 chans[ch].protocol = msg->msg.data[3] & 0x1f;
3189
3190  next_channel:
3191                 intf->curr_channel++;
3192                 if (intf->curr_channel >= IPMI_MAX_CHANNELS) {
3193                         intf->channel_list = intf->wchannels + set;
3194                         intf->channels_ready = true;
3195                         wake_up(&intf->waitq);
3196                 } else {
3197                         intf->channel_list = intf->wchannels + set;
3198                         intf->channels_ready = true;
3199                         rv = send_channel_info_cmd(intf, intf->curr_channel);
3200                 }
3201
3202                 if (rv) {
3203                         /* Got an error somehow, just give up. */
3204                         dev_warn(intf->si_dev,
3205                                  "Error sending channel information for channel %d: %d\n",
3206                                  intf->curr_channel, rv);
3207
3208                         intf->channel_list = intf->wchannels + set;
3209                         intf->channels_ready = true;
3210                         wake_up(&intf->waitq);
3211                 }
3212         }
3213  out:
3214         return;
3215 }
3216
3217 /*
3218  * Must be holding intf->bmc_reg_mutex to call this.
3219  */
3220 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id)
3221 {
3222         int rv;
3223
3224         if (ipmi_version_major(id) > 1
3225                         || (ipmi_version_major(id) == 1
3226                             && ipmi_version_minor(id) >= 5)) {
3227                 unsigned int set;
3228
3229                 /*
3230                  * Start scanning the channels to see what is
3231                  * available.
3232                  */
3233                 set = !intf->curr_working_cset;
3234                 intf->curr_working_cset = set;
3235                 memset(&intf->wchannels[set], 0,
3236                        sizeof(struct ipmi_channel_set));
3237
3238                 intf->null_user_handler = channel_handler;
3239                 intf->curr_channel = 0;
3240                 rv = send_channel_info_cmd(intf, 0);
3241                 if (rv) {
3242                         dev_warn(intf->si_dev,
3243                                  "Error sending channel information for channel 0, %d\n",
3244                                  rv);
3245                         return -EIO;
3246                 }
3247
3248                 /* Wait for the channel info to be read. */
3249                 wait_event(intf->waitq, intf->channels_ready);
3250                 intf->null_user_handler = NULL;
3251         } else {
3252                 unsigned int set = intf->curr_working_cset;
3253
3254                 /* Assume a single IPMB channel at zero. */
3255                 intf->wchannels[set].c[0].medium = IPMI_CHANNEL_MEDIUM_IPMB;
3256                 intf->wchannels[set].c[0].protocol = IPMI_CHANNEL_PROTOCOL_IPMB;
3257                 intf->channel_list = intf->wchannels + set;
3258                 intf->channels_ready = true;
3259         }
3260
3261         return 0;
3262 }
3263
3264 static void ipmi_poll(struct ipmi_smi *intf)
3265 {
3266         if (intf->handlers->poll)
3267                 intf->handlers->poll(intf->send_info);
3268         /* In case something came in */
3269         handle_new_recv_msgs(intf);
3270 }
3271
3272 void ipmi_poll_interface(struct ipmi_user *user)
3273 {
3274         ipmi_poll(user->intf);
3275 }
3276 EXPORT_SYMBOL(ipmi_poll_interface);
3277
3278 static void redo_bmc_reg(struct work_struct *work)
3279 {
3280         struct ipmi_smi *intf = container_of(work, struct ipmi_smi,
3281                                              bmc_reg_work);
3282
3283         if (!intf->in_shutdown)
3284                 bmc_get_device_id(intf, NULL, NULL, NULL, NULL);
3285
3286         kref_put(&intf->refcount, intf_free);
3287 }
3288
3289 int ipmi_register_smi(const struct ipmi_smi_handlers *handlers,
3290                       void                     *send_info,
3291                       struct device            *si_dev,
3292                       unsigned char            slave_addr)
3293 {
3294         int              i, j;
3295         int              rv;
3296         struct ipmi_smi *intf, *tintf;
3297         struct list_head *link;
3298         struct ipmi_device_id id;
3299
3300         /*
3301          * Make sure the driver is actually initialized, this handles
3302          * problems with initialization order.
3303          */
3304         rv = ipmi_init_msghandler();
3305         if (rv)
3306                 return rv;
3307
3308         intf = kzalloc(sizeof(*intf), GFP_KERNEL);
3309         if (!intf)
3310                 return -ENOMEM;
3311
3312         rv = init_srcu_struct(&intf->users_srcu);
3313         if (rv) {
3314                 kfree(intf);
3315                 return rv;
3316         }
3317
3318
3319         intf->bmc = &intf->tmp_bmc;
3320         INIT_LIST_HEAD(&intf->bmc->intfs);
3321         mutex_init(&intf->bmc->dyn_mutex);
3322         INIT_LIST_HEAD(&intf->bmc_link);
3323         mutex_init(&intf->bmc_reg_mutex);
3324         intf->intf_num = -1; /* Mark it invalid for now. */
3325         kref_init(&intf->refcount);
3326         INIT_WORK(&intf->bmc_reg_work, redo_bmc_reg);
3327         intf->si_dev = si_dev;
3328         for (j = 0; j < IPMI_MAX_CHANNELS; j++) {
3329                 intf->addrinfo[j].address = IPMI_BMC_SLAVE_ADDR;
3330                 intf->addrinfo[j].lun = 2;
3331         }
3332         if (slave_addr != 0)
3333                 intf->addrinfo[0].address = slave_addr;
3334         INIT_LIST_HEAD(&intf->users);
3335         intf->handlers = handlers;
3336         intf->send_info = send_info;
3337         spin_lock_init(&intf->seq_lock);
3338         for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) {
3339                 intf->seq_table[j].inuse = 0;
3340                 intf->seq_table[j].seqid = 0;
3341         }
3342         intf->curr_seq = 0;
3343         spin_lock_init(&intf->waiting_rcv_msgs_lock);
3344         INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
3345         tasklet_init(&intf->recv_tasklet,
3346                      smi_recv_tasklet,
3347                      (unsigned long) intf);
3348         atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0);
3349         spin_lock_init(&intf->xmit_msgs_lock);
3350         INIT_LIST_HEAD(&intf->xmit_msgs);
3351         INIT_LIST_HEAD(&intf->hp_xmit_msgs);
3352         spin_lock_init(&intf->events_lock);
3353         atomic_set(&intf->event_waiters, 0);
3354         intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
3355         INIT_LIST_HEAD(&intf->waiting_events);
3356         intf->waiting_events_count = 0;
3357         mutex_init(&intf->cmd_rcvrs_mutex);
3358         spin_lock_init(&intf->maintenance_mode_lock);
3359         INIT_LIST_HEAD(&intf->cmd_rcvrs);
3360         init_waitqueue_head(&intf->waitq);
3361         for (i = 0; i < IPMI_NUM_STATS; i++)
3362                 atomic_set(&intf->stats[i], 0);
3363
3364         mutex_lock(&ipmi_interfaces_mutex);
3365         /* Look for a hole in the numbers. */
3366         i = 0;
3367         link = &ipmi_interfaces;
3368         list_for_each_entry_rcu(tintf, &ipmi_interfaces, link) {
3369                 if (tintf->intf_num != i) {
3370                         link = &tintf->link;
3371                         break;
3372                 }
3373                 i++;
3374         }
3375         /* Add the new interface in numeric order. */
3376         if (i == 0)
3377                 list_add_rcu(&intf->link, &ipmi_interfaces);
3378         else
3379                 list_add_tail_rcu(&intf->link, link);
3380
3381         rv = handlers->start_processing(send_info, intf);
3382         if (rv)
3383                 goto out_err;
3384
3385         rv = __bmc_get_device_id(intf, NULL, &id, NULL, NULL, i);
3386         if (rv) {
3387                 dev_err(si_dev, "Unable to get the device id: %d\n", rv);
3388                 goto out_err_started;
3389         }
3390
3391         mutex_lock(&intf->bmc_reg_mutex);
3392         rv = __scan_channels(intf, &id);
3393         mutex_unlock(&intf->bmc_reg_mutex);
3394         if (rv)
3395                 goto out_err_bmc_reg;
3396
3397         /*
3398          * Keep memory order straight for RCU readers.  Make
3399          * sure everything else is committed to memory before
3400          * setting intf_num to mark the interface valid.
3401          */
3402         smp_wmb();
3403         intf->intf_num = i;
3404         mutex_unlock(&ipmi_interfaces_mutex);
3405
3406         /* After this point the interface is legal to use. */
3407         call_smi_watchers(i, intf->si_dev);
3408
3409         return 0;
3410
3411  out_err_bmc_reg:
3412         ipmi_bmc_unregister(intf);
3413  out_err_started:
3414         if (intf->handlers->shutdown)
3415                 intf->handlers->shutdown(intf->send_info);
3416  out_err:
3417         list_del_rcu(&intf->link);
3418         mutex_unlock(&ipmi_interfaces_mutex);
3419         synchronize_srcu(&ipmi_interfaces_srcu);
3420         cleanup_srcu_struct(&intf->users_srcu);
3421         kref_put(&intf->refcount, intf_free);
3422
3423         return rv;
3424 }
3425 EXPORT_SYMBOL(ipmi_register_smi);
3426
3427 static void deliver_smi_err_response(struct ipmi_smi *intf,
3428                                      struct ipmi_smi_msg *msg,
3429                                      unsigned char err)
3430 {
3431         msg->rsp[0] = msg->data[0] | 4;
3432         msg->rsp[1] = msg->data[1];
3433         msg->rsp[2] = err;
3434         msg->rsp_size = 3;
3435         /* It's an error, so it will never requeue, no need to check return. */
3436         handle_one_recv_msg(intf, msg);
3437 }
3438
3439 static void cleanup_smi_msgs(struct ipmi_smi *intf)
3440 {
3441         int              i;
3442         struct seq_table *ent;
3443         struct ipmi_smi_msg *msg;
3444         struct list_head *entry;
3445         struct list_head tmplist;
3446
3447         /* Clear out our transmit queues and hold the messages. */
3448         INIT_LIST_HEAD(&tmplist);
3449         list_splice_tail(&intf->hp_xmit_msgs, &tmplist);
3450         list_splice_tail(&intf->xmit_msgs, &tmplist);
3451
3452         /* Current message first, to preserve order */
3453         while (intf->curr_msg && !list_empty(&intf->waiting_rcv_msgs)) {
3454                 /* Wait for the message to clear out. */
3455                 schedule_timeout(1);
3456         }
3457
3458         /* No need for locks, the interface is down. */
3459
3460         /*
3461          * Return errors for all pending messages in queue and in the
3462          * tables waiting for remote responses.
3463          */
3464         while (!list_empty(&tmplist)) {
3465                 entry = tmplist.next;
3466                 list_del(entry);
3467                 msg = list_entry(entry, struct ipmi_smi_msg, link);
3468                 deliver_smi_err_response(intf, msg, IPMI_ERR_UNSPECIFIED);
3469         }
3470
3471         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
3472                 ent = &intf->seq_table[i];
3473                 if (!ent->inuse)
3474                         continue;
3475                 deliver_err_response(intf, ent->recv_msg, IPMI_ERR_UNSPECIFIED);
3476         }
3477 }
3478
3479 void ipmi_unregister_smi(struct ipmi_smi *intf)
3480 {
3481         struct ipmi_smi_watcher *w;
3482         int intf_num = intf->intf_num, index;
3483
3484         mutex_lock(&ipmi_interfaces_mutex);
3485         intf->intf_num = -1;
3486         intf->in_shutdown = true;
3487         list_del_rcu(&intf->link);
3488         mutex_unlock(&ipmi_interfaces_mutex);
3489         synchronize_srcu(&ipmi_interfaces_srcu);
3490
3491         /* At this point no users can be added to the interface. */
3492
3493         /*
3494          * Call all the watcher interfaces to tell them that
3495          * an interface is going away.
3496          */
3497         mutex_lock(&smi_watchers_mutex);
3498         list_for_each_entry(w, &smi_watchers, link)
3499                 w->smi_gone(intf_num);
3500         mutex_unlock(&smi_watchers_mutex);
3501
3502         index = srcu_read_lock(&intf->users_srcu);
3503         while (!list_empty(&intf->users)) {
3504                 struct ipmi_user *user =
3505                         container_of(list_next_rcu(&intf->users),
3506                                      struct ipmi_user, link);
3507
3508                 _ipmi_destroy_user(user);
3509         }
3510         srcu_read_unlock(&intf->users_srcu, index);
3511
3512         if (intf->handlers->shutdown)
3513                 intf->handlers->shutdown(intf->send_info);
3514
3515         cleanup_smi_msgs(intf);
3516
3517         ipmi_bmc_unregister(intf);
3518
3519         cleanup_srcu_struct(&intf->users_srcu);
3520         kref_put(&intf->refcount, intf_free);
3521 }
3522 EXPORT_SYMBOL(ipmi_unregister_smi);
3523
3524 static int handle_ipmb_get_msg_rsp(struct ipmi_smi *intf,
3525                                    struct ipmi_smi_msg *msg)
3526 {
3527         struct ipmi_ipmb_addr ipmb_addr;
3528         struct ipmi_recv_msg  *recv_msg;
3529
3530         /*
3531          * This is 11, not 10, because the response must contain a
3532          * completion code.
3533          */
3534         if (msg->rsp_size < 11) {
3535                 /* Message not big enough, just ignore it. */
3536                 ipmi_inc_stat(intf, invalid_ipmb_responses);
3537                 return 0;
3538         }
3539
3540         if (msg->rsp[2] != 0) {
3541                 /* An error getting the response, just ignore it. */
3542                 return 0;
3543         }
3544
3545         ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
3546         ipmb_addr.slave_addr = msg->rsp[6];
3547         ipmb_addr.channel = msg->rsp[3] & 0x0f;
3548         ipmb_addr.lun = msg->rsp[7] & 3;
3549
3550         /*
3551          * It's a response from a remote entity.  Look up the sequence
3552          * number and handle the response.
3553          */
3554         if (intf_find_seq(intf,
3555                           msg->rsp[7] >> 2,
3556                           msg->rsp[3] & 0x0f,
3557                           msg->rsp[8],
3558                           (msg->rsp[4] >> 2) & (~1),
3559                           (struct ipmi_addr *) &ipmb_addr,
3560                           &recv_msg)) {
3561                 /*
3562                  * We were unable to find the sequence number,
3563                  * so just nuke the message.
3564                  */
3565                 ipmi_inc_stat(intf, unhandled_ipmb_responses);
3566                 return 0;
3567         }
3568
3569         memcpy(recv_msg->msg_data, &msg->rsp[9], msg->rsp_size - 9);
3570         /*
3571          * The other fields matched, so no need to set them, except
3572          * for netfn, which needs to be the response that was
3573          * returned, not the request value.
3574          */
3575         recv_msg->msg.netfn = msg->rsp[4] >> 2;
3576         recv_msg->msg.data = recv_msg->msg_data;
3577         recv_msg->msg.data_len = msg->rsp_size - 10;
3578         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
3579         if (deliver_response(intf, recv_msg))
3580                 ipmi_inc_stat(intf, unhandled_ipmb_responses);
3581         else
3582                 ipmi_inc_stat(intf, handled_ipmb_responses);
3583
3584         return 0;
3585 }
3586
3587 static int handle_ipmb_get_msg_cmd(struct ipmi_smi *intf,
3588                                    struct ipmi_smi_msg *msg)
3589 {
3590         struct cmd_rcvr          *rcvr;
3591         int                      rv = 0;
3592         unsigned char            netfn;
3593         unsigned char            cmd;
3594         unsigned char            chan;
3595         struct ipmi_user         *user = NULL;
3596         struct ipmi_ipmb_addr    *ipmb_addr;
3597         struct ipmi_recv_msg     *recv_msg;
3598
3599         if (msg->rsp_size < 10) {
3600                 /* Message not big enough, just ignore it. */
3601                 ipmi_inc_stat(intf, invalid_commands);
3602                 return 0;
3603         }
3604
3605         if (msg->rsp[2] != 0) {
3606                 /* An error getting the response, just ignore it. */
3607                 return 0;
3608         }
3609
3610         netfn = msg->rsp[4] >> 2;
3611         cmd = msg->rsp[8];
3612         chan = msg->rsp[3] & 0xf;
3613
3614         rcu_read_lock();
3615         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3616         if (rcvr) {
3617                 user = rcvr->user;
3618                 kref_get(&user->refcount);
3619         } else
3620                 user = NULL;
3621         rcu_read_unlock();
3622
3623         if (user == NULL) {
3624                 /* We didn't find a user, deliver an error response. */
3625                 ipmi_inc_stat(intf, unhandled_commands);
3626
3627                 msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
3628                 msg->data[1] = IPMI_SEND_MSG_CMD;
3629                 msg->data[2] = msg->rsp[3];
3630                 msg->data[3] = msg->rsp[6];
3631                 msg->data[4] = ((netfn + 1) << 2) | (msg->rsp[7] & 0x3);
3632                 msg->data[5] = ipmb_checksum(&msg->data[3], 2);
3633                 msg->data[6] = intf->addrinfo[msg->rsp[3] & 0xf].address;
3634                 /* rqseq/lun */
3635                 msg->data[7] = (msg->rsp[7] & 0xfc) | (msg->rsp[4] & 0x3);
3636                 msg->data[8] = msg->rsp[8]; /* cmd */
3637                 msg->data[9] = IPMI_INVALID_CMD_COMPLETION_CODE;
3638                 msg->data[10] = ipmb_checksum(&msg->data[6], 4);
3639                 msg->data_size = 11;
3640
3641                 ipmi_debug_msg("Invalid command:", msg->data, msg->data_size);
3642
3643                 rcu_read_lock();
3644                 if (!intf->in_shutdown) {
3645                         smi_send(intf, intf->handlers, msg, 0);
3646                         /*
3647                          * We used the message, so return the value
3648                          * that causes it to not be freed or
3649                          * queued.
3650                          */
3651                         rv = -1;
3652                 }
3653                 rcu_read_unlock();
3654         } else {
3655                 recv_msg = ipmi_alloc_recv_msg();
3656                 if (!recv_msg) {
3657                         /*
3658                          * We couldn't allocate memory for the
3659                          * message, so requeue it for handling
3660                          * later.
3661                          */
3662                         rv = 1;
3663                         kref_put(&user->refcount, free_user);
3664                 } else {
3665                         /* Extract the source address from the data. */
3666                         ipmb_addr = (struct ipmi_ipmb_addr *) &recv_msg->addr;
3667                         ipmb_addr->addr_type = IPMI_IPMB_ADDR_TYPE;
3668                         ipmb_addr->slave_addr = msg->rsp[6];
3669                         ipmb_addr->lun = msg->rsp[7] & 3;
3670                         ipmb_addr->channel = msg->rsp[3] & 0xf;
3671
3672                         /*
3673                          * Extract the rest of the message information
3674                          * from the IPMB header.
3675                          */
3676                         recv_msg->user = user;
3677                         recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
3678                         recv_msg->msgid = msg->rsp[7] >> 2;
3679                         recv_msg->msg.netfn = msg->rsp[4] >> 2;
3680                         recv_msg->msg.cmd = msg->rsp[8];
3681                         recv_msg->msg.data = recv_msg->msg_data;
3682
3683                         /*
3684                          * We chop off 10, not 9 bytes because the checksum
3685                          * at the end also needs to be removed.
3686                          */
3687                         recv_msg->msg.data_len = msg->rsp_size - 10;
3688                         memcpy(recv_msg->msg_data, &msg->rsp[9],
3689                                msg->rsp_size - 10);
3690                         if (deliver_response(intf, recv_msg))
3691                                 ipmi_inc_stat(intf, unhandled_commands);
3692                         else
3693                                 ipmi_inc_stat(intf, handled_commands);
3694                 }
3695         }
3696
3697         return rv;
3698 }
3699
3700 static int handle_lan_get_msg_rsp(struct ipmi_smi *intf,
3701                                   struct ipmi_smi_msg *msg)
3702 {
3703         struct ipmi_lan_addr  lan_addr;
3704         struct ipmi_recv_msg  *recv_msg;
3705
3706
3707         /*
3708          * This is 13, not 12, because the response must contain a
3709          * completion code.
3710          */
3711         if (msg->rsp_size < 13) {
3712                 /* Message not big enough, just ignore it. */
3713                 ipmi_inc_stat(intf, invalid_lan_responses);
3714                 return 0;
3715         }
3716
3717         if (msg->rsp[2] != 0) {
3718                 /* An error getting the response, just ignore it. */
3719                 return 0;
3720         }
3721
3722         lan_addr.addr_type = IPMI_LAN_ADDR_TYPE;
3723         lan_addr.session_handle = msg->rsp[4];
3724         lan_addr.remote_SWID = msg->rsp[8];
3725         lan_addr.local_SWID = msg->rsp[5];
3726         lan_addr.channel = msg->rsp[3] & 0x0f;
3727         lan_addr.privilege = msg->rsp[3] >> 4;
3728         lan_addr.lun = msg->rsp[9] & 3;
3729
3730         /*
3731          * It's a response from a remote entity.  Look up the sequence
3732          * number and handle the response.
3733          */
3734         if (intf_find_seq(intf,
3735                           msg->rsp[9] >> 2,
3736                           msg->rsp[3] & 0x0f,
3737                           msg->rsp[10],
3738                           (msg->rsp[6] >> 2) & (~1),
3739                           (struct ipmi_addr *) &lan_addr,
3740                           &recv_msg)) {
3741                 /*
3742                  * We were unable to find the sequence number,
3743                  * so just nuke the message.
3744                  */
3745                 ipmi_inc_stat(intf, unhandled_lan_responses);
3746                 return 0;
3747         }
3748
3749         memcpy(recv_msg->msg_data, &msg->rsp[11], msg->rsp_size - 11);
3750         /*
3751          * The other fields matched, so no need to set them, except
3752          * for netfn, which needs to be the response that was
3753          * returned, not the request value.
3754          */
3755         recv_msg->msg.netfn = msg->rsp[6] >> 2;
3756         recv_msg->msg.data = recv_msg->msg_data;
3757         recv_msg->msg.data_len = msg->rsp_size - 12;
3758         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
3759         if (deliver_response(intf, recv_msg))
3760                 ipmi_inc_stat(intf, unhandled_lan_responses);
3761         else
3762                 ipmi_inc_stat(intf, handled_lan_responses);
3763
3764         return 0;
3765 }
3766
3767 static int handle_lan_get_msg_cmd(struct ipmi_smi *intf,
3768                                   struct ipmi_smi_msg *msg)
3769 {
3770         struct cmd_rcvr          *rcvr;
3771         int                      rv = 0;
3772         unsigned char            netfn;
3773         unsigned char            cmd;
3774         unsigned char            chan;
3775         struct ipmi_user         *user = NULL;
3776         struct ipmi_lan_addr     *lan_addr;
3777         struct ipmi_recv_msg     *recv_msg;
3778
3779         if (msg->rsp_size < 12) {
3780                 /* Message not big enough, just ignore it. */
3781                 ipmi_inc_stat(intf, invalid_commands);
3782                 return 0;
3783         }
3784
3785         if (msg->rsp[2] != 0) {
3786                 /* An error getting the response, just ignore it. */
3787                 return 0;
3788         }
3789
3790         netfn = msg->rsp[6] >> 2;
3791         cmd = msg->rsp[10];
3792         chan = msg->rsp[3] & 0xf;
3793
3794         rcu_read_lock();
3795         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3796         if (rcvr) {
3797                 user = rcvr->user;
3798                 kref_get(&user->refcount);
3799         } else
3800                 user = NULL;
3801         rcu_read_unlock();
3802
3803         if (user == NULL) {
3804                 /* We didn't find a user, just give up. */
3805                 ipmi_inc_stat(intf, unhandled_commands);
3806
3807                 /*
3808                  * Don't do anything with these messages, just allow
3809                  * them to be freed.
3810                  */
3811                 rv = 0;
3812         } else {
3813                 recv_msg = ipmi_alloc_recv_msg();
3814                 if (!recv_msg) {
3815                         /*
3816                          * We couldn't allocate memory for the
3817                          * message, so requeue it for handling later.
3818                          */
3819                         rv = 1;
3820                         kref_put(&user->refcount, free_user);
3821                 } else {
3822                         /* Extract the source address from the data. */
3823                         lan_addr = (struct ipmi_lan_addr *) &recv_msg->addr;
3824                         lan_addr->addr_type = IPMI_LAN_ADDR_TYPE;
3825                         lan_addr->session_handle = msg->rsp[4];
3826                         lan_addr->remote_SWID = msg->rsp[8];
3827                         lan_addr->local_SWID = msg->rsp[5];
3828                         lan_addr->lun = msg->rsp[9] & 3;
3829                         lan_addr->channel = msg->rsp[3] & 0xf;
3830                         lan_addr->privilege = msg->rsp[3] >> 4;
3831
3832                         /*
3833                          * Extract the rest of the message information
3834                          * from the IPMB header.
3835                          */
3836                         recv_msg->user = user;
3837                         recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
3838                         recv_msg->msgid = msg->rsp[9] >> 2;
3839                         recv_msg->msg.netfn = msg->rsp[6] >> 2;
3840                         recv_msg->msg.cmd = msg->rsp[10];
3841                         recv_msg->msg.data = recv_msg->msg_data;
3842
3843                         /*
3844                          * We chop off 12, not 11 bytes because the checksum
3845                          * at the end also needs to be removed.
3846                          */
3847                         recv_msg->msg.data_len = msg->rsp_size - 12;
3848                         memcpy(recv_msg->msg_data, &msg->rsp[11],
3849                                msg->rsp_size - 12);
3850                         if (deliver_response(intf, recv_msg))
3851                                 ipmi_inc_stat(intf, unhandled_commands);
3852                         else
3853                                 ipmi_inc_stat(intf, handled_commands);
3854                 }
3855         }
3856
3857         return rv;
3858 }
3859
3860 /*
3861  * This routine will handle "Get Message" command responses with
3862  * channels that use an OEM Medium. The message format belongs to
3863  * the OEM.  See IPMI 2.0 specification, Chapter 6 and
3864  * Chapter 22, sections 22.6 and 22.24 for more details.
3865  */
3866 static int handle_oem_get_msg_cmd(struct ipmi_smi *intf,
3867                                   struct ipmi_smi_msg *msg)
3868 {
3869         struct cmd_rcvr       *rcvr;
3870         int                   rv = 0;
3871         unsigned char         netfn;
3872         unsigned char         cmd;
3873         unsigned char         chan;
3874         struct ipmi_user *user = NULL;
3875         struct ipmi_system_interface_addr *smi_addr;
3876         struct ipmi_recv_msg  *recv_msg;
3877
3878         /*
3879          * We expect the OEM SW to perform error checking
3880          * so we just do some basic sanity checks
3881          */
3882         if (msg->rsp_size < 4) {
3883                 /* Message not big enough, just ignore it. */
3884                 ipmi_inc_stat(intf, invalid_commands);
3885                 return 0;
3886         }
3887
3888         if (msg->rsp[2] != 0) {
3889                 /* An error getting the response, just ignore it. */
3890                 return 0;
3891         }
3892
3893         /*
3894          * This is an OEM Message so the OEM needs to know how
3895          * handle the message. We do no interpretation.
3896          */
3897         netfn = msg->rsp[0] >> 2;
3898         cmd = msg->rsp[1];
3899         chan = msg->rsp[3] & 0xf;
3900
3901         rcu_read_lock();
3902         rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3903         if (rcvr) {
3904                 user = rcvr->user;
3905                 kref_get(&user->refcount);
3906         } else
3907                 user = NULL;
3908         rcu_read_unlock();
3909
3910         if (user == NULL) {
3911                 /* We didn't find a user, just give up. */
3912                 ipmi_inc_stat(intf, unhandled_commands);
3913
3914                 /*
3915                  * Don't do anything with these messages, just allow
3916                  * them to be freed.
3917                  */
3918
3919                 rv = 0;
3920         } else {
3921                 recv_msg = ipmi_alloc_recv_msg();
3922                 if (!recv_msg) {
3923                         /*
3924                          * We couldn't allocate memory for the
3925                          * message, so requeue it for handling
3926                          * later.
3927                          */
3928                         rv = 1;
3929                         kref_put(&user->refcount, free_user);
3930                 } else {
3931                         /*
3932                          * OEM Messages are expected to be delivered via
3933                          * the system interface to SMS software.  We might
3934                          * need to visit this again depending on OEM
3935                          * requirements
3936                          */
3937                         smi_addr = ((struct ipmi_system_interface_addr *)
3938                                     &recv_msg->addr);
3939                         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3940                         smi_addr->channel = IPMI_BMC_CHANNEL;
3941                         smi_addr->lun = msg->rsp[0] & 3;
3942
3943                         recv_msg->user = user;
3944                         recv_msg->user_msg_data = NULL;
3945                         recv_msg->recv_type = IPMI_OEM_RECV_TYPE;
3946                         recv_msg->msg.netfn = msg->rsp[0] >> 2;
3947                         recv_msg->msg.cmd = msg->rsp[1];
3948                         recv_msg->msg.data = recv_msg->msg_data;
3949
3950                         /*
3951                          * The message starts at byte 4 which follows the
3952                          * the Channel Byte in the "GET MESSAGE" command
3953                          */
3954                         recv_msg->msg.data_len = msg->rsp_size - 4;
3955                         memcpy(recv_msg->msg_data, &msg->rsp[4],
3956                                msg->rsp_size - 4);
3957                         if (deliver_response(intf, recv_msg))
3958                                 ipmi_inc_stat(intf, unhandled_commands);
3959                         else
3960                                 ipmi_inc_stat(intf, handled_commands);
3961                 }
3962         }
3963
3964         return rv;
3965 }
3966
3967 static void copy_event_into_recv_msg(struct ipmi_recv_msg *recv_msg,
3968                                      struct ipmi_smi_msg  *msg)
3969 {
3970         struct ipmi_system_interface_addr *smi_addr;
3971
3972         recv_msg->msgid = 0;
3973         smi_addr = (struct ipmi_system_interface_addr *) &recv_msg->addr;
3974         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3975         smi_addr->channel = IPMI_BMC_CHANNEL;
3976         smi_addr->lun = msg->rsp[0] & 3;
3977         recv_msg->recv_type = IPMI_ASYNC_EVENT_RECV_TYPE;
3978         recv_msg->msg.netfn = msg->rsp[0] >> 2;
3979         recv_msg->msg.cmd = msg->rsp[1];
3980         memcpy(recv_msg->msg_data, &msg->rsp[3], msg->rsp_size - 3);
3981         recv_msg->msg.data = recv_msg->msg_data;
3982         recv_msg->msg.data_len = msg->rsp_size - 3;
3983 }
3984
3985 static int handle_read_event_rsp(struct ipmi_smi *intf,
3986                                  struct ipmi_smi_msg *msg)
3987 {
3988         struct ipmi_recv_msg *recv_msg, *recv_msg2;
3989         struct list_head     msgs;
3990         struct ipmi_user     *user;
3991         int rv = 0, deliver_count = 0, index;
3992         unsigned long        flags;
3993
3994         if (msg->rsp_size < 19) {
3995                 /* Message is too small to be an IPMB event. */
3996                 ipmi_inc_stat(intf, invalid_events);
3997                 return 0;
3998         }
3999
4000         if (msg->rsp[2] != 0) {
4001                 /* An error getting the event, just ignore it. */
4002                 return 0;
4003         }
4004
4005         INIT_LIST_HEAD(&msgs);
4006
4007         spin_lock_irqsave(&intf->events_lock, flags);
4008
4009         ipmi_inc_stat(intf, events);
4010
4011         /*
4012          * Allocate and fill in one message for every user that is
4013          * getting events.
4014          */
4015         index = srcu_read_lock(&intf->users_srcu);
4016         list_for_each_entry_rcu(user, &intf->users, link) {
4017                 if (!user->gets_events)
4018                         continue;
4019
4020                 recv_msg = ipmi_alloc_recv_msg();
4021                 if (!recv_msg) {
4022                         rcu_read_unlock();
4023                         list_for_each_entry_safe(recv_msg, recv_msg2, &msgs,
4024                                                  link) {
4025                                 list_del(&recv_msg->link);
4026                                 ipmi_free_recv_msg(recv_msg);
4027                         }
4028                         /*
4029                          * We couldn't allocate memory for the
4030                          * message, so requeue it for handling
4031                          * later.
4032                          */
4033                         rv = 1;
4034                         goto out;
4035                 }
4036
4037                 deliver_count++;
4038
4039                 copy_event_into_recv_msg(recv_msg, msg);
4040                 recv_msg->user = user;
4041                 kref_get(&user->refcount);
4042                 list_add_tail(&recv_msg->link, &msgs);
4043         }
4044         srcu_read_unlock(&intf->users_srcu, index);
4045
4046         if (deliver_count) {
4047                 /* Now deliver all the messages. */
4048                 list_for_each_entry_safe(recv_msg, recv_msg2, &msgs, link) {
4049                         list_del(&recv_msg->link);
4050                         deliver_local_response(intf, recv_msg);
4051                 }
4052         } else if (intf->waiting_events_count < MAX_EVENTS_IN_QUEUE) {
4053                 /*
4054                  * No one to receive the message, put it in queue if there's
4055                  * not already too many things in the queue.
4056                  */
4057                 recv_msg = ipmi_alloc_recv_msg();
4058                 if (!recv_msg) {
4059                         /*
4060                          * We couldn't allocate memory for the
4061                          * message, so requeue it for handling
4062                          * later.
4063                          */
4064                         rv = 1;
4065                         goto out;
4066                 }
4067
4068                 copy_event_into_recv_msg(recv_msg, msg);
4069                 list_add_tail(&recv_msg->link, &intf->waiting_events);
4070                 intf->waiting_events_count++;
4071         } else if (!intf->event_msg_printed) {
4072                 /*
4073                  * There's too many things in the queue, discard this
4074                  * message.
4075                  */
4076                 dev_warn(intf->si_dev,
4077                          "Event queue full, discarding incoming events\n");
4078                 intf->event_msg_printed = 1;
4079         }
4080
4081  out:
4082         spin_unlock_irqrestore(&intf->events_lock, flags);
4083
4084         return rv;
4085 }
4086
4087 static int handle_bmc_rsp(struct ipmi_smi *intf,
4088                           struct ipmi_smi_msg *msg)
4089 {
4090         struct ipmi_recv_msg *recv_msg;
4091         struct ipmi_system_interface_addr *smi_addr;
4092
4093         recv_msg = (struct ipmi_recv_msg *) msg->user_data;
4094         if (recv_msg == NULL) {
4095                 dev_warn(intf->si_dev,
4096                          "IPMI message received with no owner. This could be because of a malformed message, or because of a hardware error.  Contact your hardware vendor for assistance.\n");
4097                 return 0;
4098         }
4099
4100         recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
4101         recv_msg->msgid = msg->msgid;
4102         smi_addr = ((struct ipmi_system_interface_addr *)
4103                     &recv_msg->addr);
4104         smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4105         smi_addr->channel = IPMI_BMC_CHANNEL;
4106         smi_addr->lun = msg->rsp[0] & 3;
4107         recv_msg->msg.netfn = msg->rsp[0] >> 2;
4108         recv_msg->msg.cmd = msg->rsp[1];
4109         memcpy(recv_msg->msg_data, &msg->rsp[2], msg->rsp_size - 2);
4110         recv_msg->msg.data = recv_msg->msg_data;
4111         recv_msg->msg.data_len = msg->rsp_size - 2;
4112         deliver_local_response(intf, recv_msg);
4113
4114         return 0;
4115 }
4116
4117 /*
4118  * Handle a received message.  Return 1 if the message should be requeued,
4119  * 0 if the message should be freed, or -1 if the message should not
4120  * be freed or requeued.
4121  */
4122 static int handle_one_recv_msg(struct ipmi_smi *intf,
4123                                struct ipmi_smi_msg *msg)
4124 {
4125         int requeue;
4126         int chan;
4127
4128         ipmi_debug_msg("Recv:", msg->rsp, msg->rsp_size);
4129         if (msg->rsp_size < 2) {
4130                 /* Message is too small to be correct. */
4131                 dev_warn(intf->si_dev,
4132                          "BMC returned too small a message for netfn %x cmd %x, got %d bytes\n",
4133                          (msg->data[0] >> 2) | 1, msg->data[1], msg->rsp_size);
4134
4135                 /* Generate an error response for the message. */
4136                 msg->rsp[0] = msg->data[0] | (1 << 2);
4137                 msg->rsp[1] = msg->data[1];
4138                 msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
4139                 msg->rsp_size = 3;
4140         } else if (((msg->rsp[0] >> 2) != ((msg->data[0] >> 2) | 1))
4141                    || (msg->rsp[1] != msg->data[1])) {
4142                 /*
4143                  * The NetFN and Command in the response is not even
4144                  * marginally correct.
4145                  */
4146                 dev_warn(intf->si_dev,
4147                          "BMC returned incorrect response, expected netfn %x cmd %x, got netfn %x cmd %x\n",
4148                          (msg->data[0] >> 2) | 1, msg->data[1],
4149                          msg->rsp[0] >> 2, msg->rsp[1]);
4150
4151                 /* Generate an error response for the message. */
4152                 msg->rsp[0] = msg->data[0] | (1 << 2);
4153                 msg->rsp[1] = msg->data[1];
4154                 msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
4155                 msg->rsp_size = 3;
4156         }
4157
4158         if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4159             && (msg->rsp[1] == IPMI_SEND_MSG_CMD)
4160             && (msg->user_data != NULL)) {
4161                 /*
4162                  * It's a response to a response we sent.  For this we
4163                  * deliver a send message response to the user.
4164                  */
4165                 struct ipmi_recv_msg *recv_msg = msg->user_data;
4166
4167                 requeue = 0;
4168                 if (msg->rsp_size < 2)
4169                         /* Message is too small to be correct. */
4170                         goto out;
4171
4172                 chan = msg->data[2] & 0x0f;
4173                 if (chan >= IPMI_MAX_CHANNELS)
4174                         /* Invalid channel number */
4175                         goto out;
4176
4177                 if (!recv_msg)
4178                         goto out;
4179
4180                 recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE;
4181                 recv_msg->msg.data = recv_msg->msg_data;
4182                 recv_msg->msg.data_len = 1;
4183                 recv_msg->msg_data[0] = msg->rsp[2];
4184                 deliver_local_response(intf, recv_msg);
4185         } else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4186                    && (msg->rsp[1] == IPMI_GET_MSG_CMD)) {
4187                 struct ipmi_channel   *chans;
4188
4189                 /* It's from the receive queue. */
4190                 chan = msg->rsp[3] & 0xf;
4191                 if (chan >= IPMI_MAX_CHANNELS) {
4192                         /* Invalid channel number */
4193                         requeue = 0;
4194                         goto out;
4195                 }
4196
4197                 /*
4198                  * We need to make sure the channels have been initialized.
4199                  * The channel_handler routine will set the "curr_channel"
4200                  * equal to or greater than IPMI_MAX_CHANNELS when all the
4201                  * channels for this interface have been initialized.
4202                  */
4203                 if (!intf->channels_ready) {
4204                         requeue = 0; /* Throw the message away */
4205                         goto out;
4206                 }
4207
4208                 chans = READ_ONCE(intf->channel_list)->c;
4209
4210                 switch (chans[chan].medium) {
4211                 case IPMI_CHANNEL_MEDIUM_IPMB:
4212                         if (msg->rsp[4] & 0x04) {
4213                                 /*
4214                                  * It's a response, so find the
4215                                  * requesting message and send it up.
4216                                  */
4217                                 requeue = handle_ipmb_get_msg_rsp(intf, msg);
4218                         } else {
4219                                 /*
4220                                  * It's a command to the SMS from some other
4221                                  * entity.  Handle that.
4222                                  */
4223                                 requeue = handle_ipmb_get_msg_cmd(intf, msg);
4224                         }
4225                         break;
4226
4227                 case IPMI_CHANNEL_MEDIUM_8023LAN:
4228                 case IPMI_CHANNEL_MEDIUM_ASYNC:
4229                         if (msg->rsp[6] & 0x04) {
4230                                 /*
4231                                  * It's a response, so find the
4232                                  * requesting message and send it up.
4233                                  */
4234                                 requeue = handle_lan_get_msg_rsp(intf, msg);
4235                         } else {
4236                                 /*
4237                                  * It's a command to the SMS from some other
4238                                  * entity.  Handle that.
4239                                  */
4240                                 requeue = handle_lan_get_msg_cmd(intf, msg);
4241                         }
4242                         break;
4243
4244                 default:
4245                         /* Check for OEM Channels.  Clients had better
4246                            register for these commands. */
4247                         if ((chans[chan].medium >= IPMI_CHANNEL_MEDIUM_OEM_MIN)
4248                             && (chans[chan].medium
4249                                 <= IPMI_CHANNEL_MEDIUM_OEM_MAX)) {
4250                                 requeue = handle_oem_get_msg_cmd(intf, msg);
4251                         } else {
4252                                 /*
4253                                  * We don't handle the channel type, so just
4254                                  * free the message.
4255                                  */
4256                                 requeue = 0;
4257                         }
4258                 }
4259
4260         } else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4261                    && (msg->rsp[1] == IPMI_READ_EVENT_MSG_BUFFER_CMD)) {
4262                 /* It's an asynchronous event. */
4263                 requeue = handle_read_event_rsp(intf, msg);
4264         } else {
4265                 /* It's a response from the local BMC. */
4266                 requeue = handle_bmc_rsp(intf, msg);
4267         }
4268
4269  out:
4270         return requeue;
4271 }
4272
4273 /*
4274  * If there are messages in the queue or pretimeouts, handle them.
4275  */
4276 static void handle_new_recv_msgs(struct ipmi_smi *intf)
4277 {
4278         struct ipmi_smi_msg  *smi_msg;
4279         unsigned long        flags = 0;
4280         int                  rv;
4281         int                  run_to_completion = intf->run_to_completion;
4282
4283         /* See if any waiting messages need to be processed. */
4284         if (!run_to_completion)
4285                 spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4286         while (!list_empty(&intf->waiting_rcv_msgs)) {
4287                 smi_msg = list_entry(intf->waiting_rcv_msgs.next,
4288                                      struct ipmi_smi_msg, link);
4289                 list_del(&smi_msg->link);
4290                 if (!run_to_completion)
4291                         spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4292                                                flags);
4293                 rv = handle_one_recv_msg(intf, smi_msg);
4294                 if (!run_to_completion)
4295                         spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4296                 if (rv > 0) {
4297                         /*
4298                          * To preserve message order, quit if we
4299                          * can't handle a message.  Add the message
4300                          * back at the head, this is safe because this
4301                          * tasklet is the only thing that pulls the
4302                          * messages.
4303                          */
4304                         list_add(&smi_msg->link, &intf->waiting_rcv_msgs);
4305                         break;
4306                 } else {
4307                         if (rv == 0)
4308                                 /* Message handled */
4309                                 ipmi_free_smi_msg(smi_msg);
4310                         /* If rv < 0, fatal error, del but don't free. */
4311                 }
4312         }
4313         if (!run_to_completion)
4314                 spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock, flags);
4315
4316         /*
4317          * If the pretimout count is non-zero, decrement one from it and
4318          * deliver pretimeouts to all the users.
4319          */
4320         if (atomic_add_unless(&intf->watchdog_pretimeouts_to_deliver, -1, 0)) {
4321                 struct ipmi_user *user;
4322                 int index;
4323
4324                 index = srcu_read_lock(&intf->users_srcu);
4325                 list_for_each_entry_rcu(user, &intf->users, link) {
4326                         if (user->handler->ipmi_watchdog_pretimeout)
4327                                 user->handler->ipmi_watchdog_pretimeout(
4328                                         user->handler_data);
4329                 }
4330                 srcu_read_unlock(&intf->users_srcu, index);
4331         }
4332 }
4333
4334 static void smi_recv_tasklet(unsigned long val)
4335 {
4336         unsigned long flags = 0; /* keep us warning-free. */
4337         struct ipmi_smi *intf = (struct ipmi_smi *) val;
4338         int run_to_completion = intf->run_to_completion;
4339         struct ipmi_smi_msg *newmsg = NULL;
4340
4341         /*
4342          * Start the next message if available.
4343          *
4344          * Do this here, not in the actual receiver, because we may deadlock
4345          * because the lower layer is allowed to hold locks while calling
4346          * message delivery.
4347          */
4348
4349         rcu_read_lock();
4350
4351         if (!run_to_completion)
4352                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4353         if (intf->curr_msg == NULL && !intf->in_shutdown) {
4354                 struct list_head *entry = NULL;
4355
4356                 /* Pick the high priority queue first. */
4357                 if (!list_empty(&intf->hp_xmit_msgs))
4358                         entry = intf->hp_xmit_msgs.next;
4359                 else if (!list_empty(&intf->xmit_msgs))
4360                         entry = intf->xmit_msgs.next;
4361
4362                 if (entry) {
4363                         list_del(entry);
4364                         newmsg = list_entry(entry, struct ipmi_smi_msg, link);
4365                         intf->curr_msg = newmsg;
4366                 }
4367         }
4368         if (!run_to_completion)
4369                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4370         if (newmsg)
4371                 intf->handlers->sender(intf->send_info, newmsg);
4372
4373         rcu_read_unlock();
4374
4375         handle_new_recv_msgs(intf);
4376 }
4377
4378 /* Handle a new message from the lower layer. */
4379 void ipmi_smi_msg_received(struct ipmi_smi *intf,
4380                            struct ipmi_smi_msg *msg)
4381 {
4382         unsigned long flags = 0; /* keep us warning-free. */
4383         int run_to_completion = intf->run_to_completion;
4384
4385         if ((msg->data_size >= 2)
4386             && (msg->data[0] == (IPMI_NETFN_APP_REQUEST << 2))
4387             && (msg->data[1] == IPMI_SEND_MSG_CMD)
4388             && (msg->user_data == NULL)) {
4389
4390                 if (intf->in_shutdown)
4391                         goto free_msg;
4392
4393                 /*
4394                  * This is the local response to a command send, start
4395                  * the timer for these.  The user_data will not be
4396                  * NULL if this is a response send, and we will let
4397                  * response sends just go through.
4398                  */
4399
4400                 /*
4401                  * Check for errors, if we get certain errors (ones
4402                  * that mean basically we can try again later), we
4403                  * ignore them and start the timer.  Otherwise we
4404                  * report the error immediately.
4405                  */
4406                 if ((msg->rsp_size >= 3) && (msg->rsp[2] != 0)
4407                     && (msg->rsp[2] != IPMI_NODE_BUSY_ERR)
4408                     && (msg->rsp[2] != IPMI_LOST_ARBITRATION_ERR)
4409                     && (msg->rsp[2] != IPMI_BUS_ERR)
4410                     && (msg->rsp[2] != IPMI_NAK_ON_WRITE_ERR)) {
4411                         int ch = msg->rsp[3] & 0xf;
4412                         struct ipmi_channel *chans;
4413
4414                         /* Got an error sending the message, handle it. */
4415
4416                         chans = READ_ONCE(intf->channel_list)->c;
4417                         if ((chans[ch].medium == IPMI_CHANNEL_MEDIUM_8023LAN)
4418                             || (chans[ch].medium == IPMI_CHANNEL_MEDIUM_ASYNC))
4419                                 ipmi_inc_stat(intf, sent_lan_command_errs);
4420                         else
4421                                 ipmi_inc_stat(intf, sent_ipmb_command_errs);
4422                         intf_err_seq(intf, msg->msgid, msg->rsp[2]);
4423                 } else
4424                         /* The message was sent, start the timer. */
4425                         intf_start_seq_timer(intf, msg->msgid);
4426
4427 free_msg:
4428                 ipmi_free_smi_msg(msg);
4429         } else {
4430                 /*
4431                  * To preserve message order, we keep a queue and deliver from
4432                  * a tasklet.
4433                  */
4434                 if (!run_to_completion)
4435                         spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4436                 list_add_tail(&msg->link, &intf->waiting_rcv_msgs);
4437                 if (!run_to_completion)
4438                         spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4439                                                flags);
4440         }
4441
4442         if (!run_to_completion)
4443                 spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4444         /*
4445          * We can get an asynchronous event or receive message in addition
4446          * to commands we send.
4447          */
4448         if (msg == intf->curr_msg)
4449                 intf->curr_msg = NULL;
4450         if (!run_to_completion)
4451                 spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4452
4453         if (run_to_completion)
4454                 smi_recv_tasklet((unsigned long) intf);
4455         else
4456                 tasklet_schedule(&intf->recv_tasklet);
4457 }
4458 EXPORT_SYMBOL(ipmi_smi_msg_received);
4459
4460 void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf)
4461 {
4462         if (intf->in_shutdown)
4463                 return;
4464
4465         atomic_set(&intf->watchdog_pretimeouts_to_deliver, 1);
4466         tasklet_schedule(&intf->recv_tasklet);
4467 }
4468 EXPORT_SYMBOL(ipmi_smi_watchdog_pretimeout);
4469
4470 static struct ipmi_smi_msg *
4471 smi_from_recv_msg(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg,
4472                   unsigned char seq, long seqid)
4473 {
4474         struct ipmi_smi_msg *smi_msg = ipmi_alloc_smi_msg();
4475         if (!smi_msg)
4476                 /*
4477                  * If we can't allocate the message, then just return, we
4478                  * get 4 retries, so this should be ok.
4479                  */
4480                 return NULL;
4481
4482         memcpy(smi_msg->data, recv_msg->msg.data, recv_msg->msg.data_len);
4483         smi_msg->data_size = recv_msg->msg.data_len;
4484         smi_msg->msgid = STORE_SEQ_IN_MSGID(seq, seqid);
4485
4486         ipmi_debug_msg("Resend: ", smi_msg->data, smi_msg->data_size);
4487
4488         return smi_msg;
4489 }
4490
4491 static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
4492                               struct list_head *timeouts,
4493                               unsigned long timeout_period,
4494                               int slot, unsigned long *flags,
4495                               unsigned int *waiting_msgs)
4496 {
4497         struct ipmi_recv_msg *msg;
4498
4499         if (intf->in_shutdown)
4500                 return;
4501
4502         if (!ent->inuse)
4503                 return;
4504
4505         if (timeout_period < ent->timeout) {
4506                 ent->timeout -= timeout_period;
4507                 (*waiting_msgs)++;
4508                 return;
4509         }
4510
4511         if (ent->retries_left == 0) {
4512                 /* The message has used all its retries. */
4513                 ent->inuse = 0;
4514                 msg = ent->recv_msg;
4515                 list_add_tail(&msg->link, timeouts);
4516                 if (ent->broadcast)
4517                         ipmi_inc_stat(intf, timed_out_ipmb_broadcasts);
4518                 else if (is_lan_addr(&ent->recv_msg->addr))
4519                         ipmi_inc_stat(intf, timed_out_lan_commands);
4520                 else
4521                         ipmi_inc_stat(intf, timed_out_ipmb_commands);
4522         } else {
4523                 struct ipmi_smi_msg *smi_msg;
4524                 /* More retries, send again. */
4525
4526                 (*waiting_msgs)++;
4527
4528                 /*
4529                  * Start with the max timer, set to normal timer after
4530                  * the message is sent.
4531                  */
4532                 ent->timeout = MAX_MSG_TIMEOUT;
4533                 ent->retries_left--;
4534                 smi_msg = smi_from_recv_msg(intf, ent->recv_msg, slot,
4535                                             ent->seqid);
4536                 if (!smi_msg) {
4537                         if (is_lan_addr(&ent->recv_msg->addr))
4538                                 ipmi_inc_stat(intf,
4539                                               dropped_rexmit_lan_commands);
4540                         else
4541                                 ipmi_inc_stat(intf,
4542                                               dropped_rexmit_ipmb_commands);
4543                         return;
4544                 }
4545
4546                 spin_unlock_irqrestore(&intf->seq_lock, *flags);
4547
4548                 /*
4549                  * Send the new message.  We send with a zero
4550                  * priority.  It timed out, I doubt time is that
4551                  * critical now, and high priority messages are really
4552                  * only for messages to the local MC, which don't get
4553                  * resent.
4554                  */
4555                 if (intf->handlers) {
4556                         if (is_lan_addr(&ent->recv_msg->addr))
4557                                 ipmi_inc_stat(intf,
4558                                               retransmitted_lan_commands);
4559                         else
4560                                 ipmi_inc_stat(intf,
4561                                               retransmitted_ipmb_commands);
4562
4563                         smi_send(intf, intf->handlers, smi_msg, 0);
4564                 } else
4565                         ipmi_free_smi_msg(smi_msg);
4566
4567                 spin_lock_irqsave(&intf->seq_lock, *flags);
4568         }
4569 }
4570
4571 static unsigned int ipmi_timeout_handler(struct ipmi_smi *intf,
4572                                          unsigned long timeout_period)
4573 {
4574         struct list_head     timeouts;
4575         struct ipmi_recv_msg *msg, *msg2;
4576         unsigned long        flags;
4577         int                  i;
4578         unsigned int         waiting_msgs = 0;
4579
4580         if (!intf->bmc_registered) {
4581                 kref_get(&intf->refcount);
4582                 if (!schedule_work(&intf->bmc_reg_work)) {
4583                         kref_put(&intf->refcount, intf_free);
4584                         waiting_msgs++;
4585                 }
4586         }
4587
4588         /*
4589          * Go through the seq table and find any messages that
4590          * have timed out, putting them in the timeouts
4591          * list.
4592          */
4593         INIT_LIST_HEAD(&timeouts);
4594         spin_lock_irqsave(&intf->seq_lock, flags);
4595         if (intf->ipmb_maintenance_mode_timeout) {
4596                 if (intf->ipmb_maintenance_mode_timeout <= timeout_period)
4597                         intf->ipmb_maintenance_mode_timeout = 0;
4598                 else
4599                         intf->ipmb_maintenance_mode_timeout -= timeout_period;
4600         }
4601         for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
4602                 check_msg_timeout(intf, &intf->seq_table[i],
4603                                   &timeouts, timeout_period, i,
4604                                   &flags, &waiting_msgs);
4605         spin_unlock_irqrestore(&intf->seq_lock, flags);
4606
4607         list_for_each_entry_safe(msg, msg2, &timeouts, link)
4608                 deliver_err_response(intf, msg, IPMI_TIMEOUT_COMPLETION_CODE);
4609
4610         /*
4611          * Maintenance mode handling.  Check the timeout
4612          * optimistically before we claim the lock.  It may
4613          * mean a timeout gets missed occasionally, but that
4614          * only means the timeout gets extended by one period
4615          * in that case.  No big deal, and it avoids the lock
4616          * most of the time.
4617          */
4618         if (intf->auto_maintenance_timeout > 0) {
4619                 spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
4620                 if (intf->auto_maintenance_timeout > 0) {
4621                         intf->auto_maintenance_timeout
4622                                 -= timeout_period;
4623                         if (!intf->maintenance_mode
4624                             && (intf->auto_maintenance_timeout <= 0)) {
4625                                 intf->maintenance_mode_enable = false;
4626                                 maintenance_mode_update(intf);
4627                         }
4628                 }
4629                 spin_unlock_irqrestore(&intf->maintenance_mode_lock,
4630                                        flags);
4631         }
4632
4633         tasklet_schedule(&intf->recv_tasklet);
4634
4635         return waiting_msgs;
4636 }
4637
4638 static void ipmi_request_event(struct ipmi_smi *intf)
4639 {
4640         /* No event requests when in maintenance mode. */
4641         if (intf->maintenance_mode_enable)
4642                 return;
4643
4644         if (!intf->in_shutdown)
4645                 intf->handlers->request_events(intf->send_info);
4646 }
4647
4648 static struct timer_list ipmi_timer;
4649
4650 static atomic_t stop_operation;
4651
4652 static void ipmi_timeout(struct timer_list *unused)
4653 {
4654         struct ipmi_smi *intf;
4655         int nt = 0, index;
4656
4657         if (atomic_read(&stop_operation))
4658                 return;
4659
4660         index = srcu_read_lock(&ipmi_interfaces_srcu);
4661         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
4662                 int lnt = 0;
4663
4664                 if (atomic_read(&intf->event_waiters)) {
4665                         intf->ticks_to_req_ev--;
4666                         if (intf->ticks_to_req_ev == 0) {
4667                                 ipmi_request_event(intf);
4668                                 intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
4669                         }
4670                         lnt++;
4671                 }
4672
4673                 lnt += ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
4674
4675                 lnt = !!lnt;
4676                 if (lnt != intf->last_needs_timer &&
4677                                         intf->handlers->set_need_watch)
4678                         intf->handlers->set_need_watch(intf->send_info, lnt);
4679                 intf->last_needs_timer = lnt;
4680
4681                 nt += lnt;
4682         }
4683         srcu_read_unlock(&ipmi_interfaces_srcu, index);
4684
4685         if (nt)
4686                 mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
4687 }
4688
4689 static void need_waiter(struct ipmi_smi *intf)
4690 {
4691         /* Racy, but worst case we start the timer twice. */
4692         if (!timer_pending(&ipmi_timer))
4693                 mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
4694 }
4695
4696 static atomic_t smi_msg_inuse_count = ATOMIC_INIT(0);
4697 static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);
4698
4699 static void free_smi_msg(struct ipmi_smi_msg *msg)
4700 {
4701         atomic_dec(&smi_msg_inuse_count);
4702         kfree(msg);
4703 }
4704
4705 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
4706 {
4707         struct ipmi_smi_msg *rv;
4708         rv = kmalloc(sizeof(struct ipmi_smi_msg), GFP_ATOMIC);
4709         if (rv) {
4710                 rv->done = free_smi_msg;
4711                 rv->user_data = NULL;
4712                 atomic_inc(&smi_msg_inuse_count);
4713         }
4714         return rv;
4715 }
4716 EXPORT_SYMBOL(ipmi_alloc_smi_msg);
4717
4718 static void free_recv_msg(struct ipmi_recv_msg *msg)
4719 {
4720         atomic_dec(&recv_msg_inuse_count);
4721         kfree(msg);
4722 }
4723
4724 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
4725 {
4726         struct ipmi_recv_msg *rv;
4727
4728         rv = kmalloc(sizeof(struct ipmi_recv_msg), GFP_ATOMIC);
4729         if (rv) {
4730                 rv->user = NULL;
4731                 rv->done = free_recv_msg;
4732                 atomic_inc(&recv_msg_inuse_count);
4733         }
4734         return rv;
4735 }
4736
4737 void ipmi_free_recv_msg(struct ipmi_recv_msg *msg)
4738 {
4739         if (msg->user)
4740                 kref_put(&msg->user->refcount, free_user);
4741         msg->done(msg);
4742 }
4743 EXPORT_SYMBOL(ipmi_free_recv_msg);
4744
4745 static atomic_t panic_done_count = ATOMIC_INIT(0);
4746
4747 static void dummy_smi_done_handler(struct ipmi_smi_msg *msg)
4748 {
4749         atomic_dec(&panic_done_count);
4750 }
4751
4752 static void dummy_recv_done_handler(struct ipmi_recv_msg *msg)
4753 {
4754         atomic_dec(&panic_done_count);
4755 }
4756
4757 /*
4758  * Inside a panic, send a message and wait for a response.
4759  */
4760 static void ipmi_panic_request_and_wait(struct ipmi_smi *intf,
4761                                         struct ipmi_addr *addr,
4762                                         struct kernel_ipmi_msg *msg)
4763 {
4764         struct ipmi_smi_msg  smi_msg;
4765         struct ipmi_recv_msg recv_msg;
4766         int rv;
4767
4768         smi_msg.done = dummy_smi_done_handler;
4769         recv_msg.done = dummy_recv_done_handler;
4770         atomic_add(2, &panic_done_count);
4771         rv = i_ipmi_request(NULL,
4772                             intf,
4773                             addr,
4774                             0,
4775                             msg,
4776                             intf,
4777                             &smi_msg,
4778                             &recv_msg,
4779                             0,
4780                             intf->addrinfo[0].address,
4781                             intf->addrinfo[0].lun,
4782                             0, 1); /* Don't retry, and don't wait. */
4783         if (rv)
4784                 atomic_sub(2, &panic_done_count);
4785         else if (intf->handlers->flush_messages)
4786                 intf->handlers->flush_messages(intf->send_info);
4787
4788         while (atomic_read(&panic_done_count) != 0)
4789                 ipmi_poll(intf);
4790 }
4791
4792 static void event_receiver_fetcher(struct ipmi_smi *intf,
4793                                    struct ipmi_recv_msg *msg)
4794 {
4795         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
4796             && (msg->msg.netfn == IPMI_NETFN_SENSOR_EVENT_RESPONSE)
4797             && (msg->msg.cmd == IPMI_GET_EVENT_RECEIVER_CMD)
4798             && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
4799                 /* A get event receiver command, save it. */
4800                 intf->event_receiver = msg->msg.data[1];
4801                 intf->event_receiver_lun = msg->msg.data[2] & 0x3;
4802         }
4803 }
4804
4805 static void device_id_fetcher(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
4806 {
4807         if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
4808             && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
4809             && (msg->msg.cmd == IPMI_GET_DEVICE_ID_CMD)
4810             && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
4811                 /*
4812                  * A get device id command, save if we are an event
4813                  * receiver or generator.
4814                  */
4815                 intf->local_sel_device = (msg->msg.data[6] >> 2) & 1;
4816                 intf->local_event_generator = (msg->msg.data[6] >> 5) & 1;
4817         }
4818 }
4819
4820 static void send_panic_events(struct ipmi_smi *intf, char *str)
4821 {
4822         struct kernel_ipmi_msg msg;
4823         unsigned char data[16];
4824         struct ipmi_system_interface_addr *si;
4825         struct ipmi_addr addr;
4826         char *p = str;
4827         struct ipmi_ipmb_addr *ipmb;
4828         int j;
4829
4830         if (ipmi_send_panic_event == IPMI_SEND_PANIC_EVENT_NONE)
4831                 return;
4832
4833         si = (struct ipmi_system_interface_addr *) &addr;
4834         si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4835         si->channel = IPMI_BMC_CHANNEL;
4836         si->lun = 0;
4837
4838         /* Fill in an event telling that we have failed. */
4839         msg.netfn = 0x04; /* Sensor or Event. */
4840         msg.cmd = 2; /* Platform event command. */
4841         msg.data = data;
4842         msg.data_len = 8;
4843         data[0] = 0x41; /* Kernel generator ID, IPMI table 5-4 */
4844         data[1] = 0x03; /* This is for IPMI 1.0. */
4845         data[2] = 0x20; /* OS Critical Stop, IPMI table 36-3 */
4846         data[4] = 0x6f; /* Sensor specific, IPMI table 36-1 */
4847         data[5] = 0xa1; /* Runtime stop OEM bytes 2 & 3. */
4848
4849         /*
4850          * Put a few breadcrumbs in.  Hopefully later we can add more things
4851          * to make the panic events more useful.
4852          */
4853         if (str) {
4854                 data[3] = str[0];
4855                 data[6] = str[1];
4856                 data[7] = str[2];
4857         }
4858
4859         /* Send the event announcing the panic. */
4860         ipmi_panic_request_and_wait(intf, &addr, &msg);
4861
4862         /*
4863          * On every interface, dump a bunch of OEM event holding the
4864          * string.
4865          */
4866         if (ipmi_send_panic_event != IPMI_SEND_PANIC_EVENT_STRING || !str)
4867                 return;
4868
4869         /*
4870          * intf_num is used as an marker to tell if the
4871          * interface is valid.  Thus we need a read barrier to
4872          * make sure data fetched before checking intf_num
4873          * won't be used.
4874          */
4875         smp_rmb();
4876
4877         /*
4878          * First job here is to figure out where to send the
4879          * OEM events.  There's no way in IPMI to send OEM
4880          * events using an event send command, so we have to
4881          * find the SEL to put them in and stick them in
4882          * there.
4883          */
4884
4885         /* Get capabilities from the get device id. */
4886         intf->local_sel_device = 0;
4887         intf->local_event_generator = 0;
4888         intf->event_receiver = 0;
4889
4890         /* Request the device info from the local MC. */
4891         msg.netfn = IPMI_NETFN_APP_REQUEST;
4892         msg.cmd = IPMI_GET_DEVICE_ID_CMD;
4893         msg.data = NULL;
4894         msg.data_len = 0;
4895         intf->null_user_handler = device_id_fetcher;
4896         ipmi_panic_request_and_wait(intf, &addr, &msg);
4897
4898         if (intf->local_event_generator) {
4899                 /* Request the event receiver from the local MC. */
4900                 msg.netfn = IPMI_NETFN_SENSOR_EVENT_REQUEST;
4901                 msg.cmd = IPMI_GET_EVENT_RECEIVER_CMD;
4902                 msg.data = NULL;
4903                 msg.data_len = 0;
4904                 intf->null_user_handler = event_receiver_fetcher;
4905                 ipmi_panic_request_and_wait(intf, &addr, &msg);
4906         }
4907         intf->null_user_handler = NULL;
4908
4909         /*
4910          * Validate the event receiver.  The low bit must not
4911          * be 1 (it must be a valid IPMB address), it cannot
4912          * be zero, and it must not be my address.
4913          */
4914         if (((intf->event_receiver & 1) == 0)
4915             && (intf->event_receiver != 0)
4916             && (intf->event_receiver != intf->addrinfo[0].address)) {
4917                 /*
4918                  * The event receiver is valid, send an IPMB
4919                  * message.
4920                  */
4921                 ipmb = (struct ipmi_ipmb_addr *) &addr;
4922                 ipmb->addr_type = IPMI_IPMB_ADDR_TYPE;
4923                 ipmb->channel = 0; /* FIXME - is this right? */
4924                 ipmb->lun = intf->event_receiver_lun;
4925                 ipmb->slave_addr = intf->event_receiver;
4926         } else if (intf->local_sel_device) {
4927                 /*
4928                  * The event receiver was not valid (or was
4929                  * me), but I am an SEL device, just dump it
4930                  * in my SEL.
4931                  */
4932                 si = (struct ipmi_system_interface_addr *) &addr;
4933                 si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4934                 si->channel = IPMI_BMC_CHANNEL;
4935                 si->lun = 0;
4936         } else
4937                 return; /* No where to send the event. */
4938
4939         msg.netfn = IPMI_NETFN_STORAGE_REQUEST; /* Storage. */
4940         msg.cmd = IPMI_ADD_SEL_ENTRY_CMD;
4941         msg.data = data;
4942         msg.data_len = 16;
4943
4944         j = 0;
4945         while (*p) {
4946                 int size = strlen(p);
4947
4948                 if (size > 11)
4949                         size = 11;
4950                 data[0] = 0;
4951                 data[1] = 0;
4952                 data[2] = 0xf0; /* OEM event without timestamp. */
4953                 data[3] = intf->addrinfo[0].address;
4954                 data[4] = j++; /* sequence # */
4955                 /*
4956                  * Always give 11 bytes, so strncpy will fill
4957                  * it with zeroes for me.
4958                  */
4959                 strncpy(data+5, p, 11);
4960                 p += size;
4961
4962                 ipmi_panic_request_and_wait(intf, &addr, &msg);
4963         }
4964 }
4965
4966 static int has_panicked;
4967
4968 static int panic_event(struct notifier_block *this,
4969                        unsigned long         event,
4970                        void                  *ptr)
4971 {
4972         struct ipmi_smi *intf;
4973         struct ipmi_user *user;
4974
4975         if (has_panicked)
4976                 return NOTIFY_DONE;
4977         has_panicked = 1;
4978
4979         /* For every registered interface, set it to run to completion. */
4980         list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
4981                 if (!intf->handlers || intf->intf_num == -1)
4982                         /* Interface is not ready. */
4983                         continue;
4984
4985                 if (!intf->handlers->poll)
4986                         continue;
4987
4988                 /*
4989                  * If we were interrupted while locking xmit_msgs_lock or
4990                  * waiting_rcv_msgs_lock, the corresponding list may be
4991                  * corrupted.  In this case, drop items on the list for
4992                  * the safety.
4993                  */
4994                 if (!spin_trylock(&intf->xmit_msgs_lock)) {
4995                         INIT_LIST_HEAD(&intf->xmit_msgs);
4996                         INIT_LIST_HEAD(&intf->hp_xmit_msgs);
4997                 } else
4998                         spin_unlock(&intf->xmit_msgs_lock);
4999
5000                 if (!spin_trylock(&intf->waiting_rcv_msgs_lock))
5001                         INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
5002                 else
5003                         spin_unlock(&intf->waiting_rcv_msgs_lock);
5004
5005                 intf->run_to_completion = 1;
5006                 if (intf->handlers->set_run_to_completion)
5007                         intf->handlers->set_run_to_completion(intf->send_info,
5008                                                               1);
5009
5010                 list_for_each_entry_rcu(user, &intf->users, link) {
5011                         if (user->handler->ipmi_panic_handler)
5012                                 user->handler->ipmi_panic_handler(
5013                                         user->handler_data);
5014                 }
5015
5016                 send_panic_events(intf, ptr);
5017         }
5018
5019         return NOTIFY_DONE;
5020 }
5021
5022 /* Must be called with ipmi_interfaces_mutex held. */
5023 static int ipmi_register_driver(void)
5024 {
5025         int rv;
5026
5027         if (drvregistered)
5028                 return 0;
5029
5030         rv = driver_register(&ipmidriver.driver);
5031         if (rv)
5032                 pr_err("Could not register IPMI driver\n");
5033         else
5034                 drvregistered = true;
5035         return rv;
5036 }
5037
5038 static struct notifier_block panic_block = {
5039         .notifier_call  = panic_event,
5040         .next           = NULL,
5041         .priority       = 200   /* priority: INT_MAX >= x >= 0 */
5042 };
5043
5044 static int ipmi_init_msghandler(void)
5045 {
5046         int rv;
5047
5048         mutex_lock(&ipmi_interfaces_mutex);
5049         rv = ipmi_register_driver();
5050         if (rv)
5051                 goto out;
5052         if (initialized)
5053                 goto out;
5054
5055         init_srcu_struct(&ipmi_interfaces_srcu);
5056
5057         timer_setup(&ipmi_timer, ipmi_timeout, 0);
5058         mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
5059
5060         atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
5061
5062         initialized = true;
5063
5064 out:
5065         mutex_unlock(&ipmi_interfaces_mutex);
5066         return rv;
5067 }
5068
5069 static int __init ipmi_init_msghandler_mod(void)
5070 {
5071         int rv;
5072
5073         pr_info("version " IPMI_DRIVER_VERSION "\n");
5074
5075         mutex_lock(&ipmi_interfaces_mutex);
5076         rv = ipmi_register_driver();
5077         mutex_unlock(&ipmi_interfaces_mutex);
5078
5079         return rv;
5080 }
5081
5082 static void __exit cleanup_ipmi(void)
5083 {
5084         int count;
5085
5086         if (initialized) {
5087                 atomic_notifier_chain_unregister(&panic_notifier_list,
5088                                                  &panic_block);
5089
5090                 /*
5091                  * This can't be called if any interfaces exist, so no worry
5092                  * about shutting down the interfaces.
5093                  */
5094
5095                 /*
5096                  * Tell the timer to stop, then wait for it to stop.  This
5097                  * avoids problems with race conditions removing the timer
5098                  * here.
5099                  */
5100                 atomic_inc(&stop_operation);
5101                 del_timer_sync(&ipmi_timer);
5102
5103                 initialized = false;
5104
5105                 /* Check for buffer leaks. */
5106                 count = atomic_read(&smi_msg_inuse_count);
5107                 if (count != 0)
5108                         pr_warn("SMI message count %d at exit\n", count);
5109                 count = atomic_read(&recv_msg_inuse_count);
5110                 if (count != 0)
5111                         pr_warn("recv message count %d at exit\n", count);
5112
5113                 cleanup_srcu_struct(&ipmi_interfaces_srcu);
5114         }
5115         if (drvregistered)
5116                 driver_unregister(&ipmidriver.driver);
5117 }
5118 module_exit(cleanup_ipmi);
5119
5120 module_init(ipmi_init_msghandler_mod);
5121 MODULE_LICENSE("GPL");
5122 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
5123 MODULE_DESCRIPTION("Incoming and outgoing message routing for an IPMI"
5124                    " interface.");
5125 MODULE_VERSION(IPMI_DRIVER_VERSION);
5126 MODULE_SOFTDEP("post: ipmi_devintf");