Merge git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
[sfrench/cifs-2.6.git] / drivers / char / viotape.c
1 /* -*- linux-c -*-
2  *  drivers/char/viotape.c
3  *
4  *  iSeries Virtual Tape
5  *
6  *  Authors: Dave Boutcher <boutcher@us.ibm.com>
7  *           Ryan Arnold <ryanarn@us.ibm.com>
8  *           Colin Devilbiss <devilbis@us.ibm.com>
9  *           Stephen Rothwell <sfr@au1.ibm.com>
10  *
11  * (C) Copyright 2000-2004 IBM Corporation
12  *
13  * This program is free software;  you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License as
15  * published by the Free Software Foundation; either version 2 of the
16  * License, or (at your option) anyu later version.
17  *
18  * This program is distributed in the hope that it will be useful, but
19  * WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21  * General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software Foundation,
25  * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26  *
27  * This routine provides access to tape drives owned and managed by an OS/400
28  * partition running on the same box as this Linux partition.
29  *
30  * All tape operations are performed by sending messages back and forth to
31  * the OS/400 partition.  The format of the messages is defined in
32  * iseries/vio.h
33  */
34 #include <linux/module.h>
35 #include <linux/kernel.h>
36 #include <linux/errno.h>
37 #include <linux/init.h>
38 #include <linux/wait.h>
39 #include <linux/spinlock.h>
40 #include <linux/mtio.h>
41 #include <linux/device.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/fs.h>
44 #include <linux/cdev.h>
45 #include <linux/major.h>
46 #include <linux/completion.h>
47 #include <linux/proc_fs.h>
48 #include <linux/seq_file.h>
49
50 #include <asm/uaccess.h>
51 #include <asm/ioctls.h>
52 #include <asm/firmware.h>
53 #include <asm/vio.h>
54 #include <asm/iseries/vio.h>
55 #include <asm/iseries/hv_lp_event.h>
56 #include <asm/iseries/hv_call_event.h>
57 #include <asm/iseries/hv_lp_config.h>
58
59 #define VIOTAPE_VERSION         "1.2"
60 #define VIOTAPE_MAXREQ          1
61
62 #define VIOTAPE_KERN_WARN       KERN_WARNING "viotape: "
63 #define VIOTAPE_KERN_INFO       KERN_INFO "viotape: "
64
65 static int viotape_numdev;
66
67 /*
68  * The minor number follows the conventions of the SCSI tape drives.  The
69  * rewind and mode are encoded in the minor #.  We use this struct to break
70  * them out
71  */
72 struct viot_devinfo_struct {
73         int devno;
74         int mode;
75         int rewind;
76 };
77
78 #define VIOTAPOP_RESET          0
79 #define VIOTAPOP_FSF            1
80 #define VIOTAPOP_BSF            2
81 #define VIOTAPOP_FSR            3
82 #define VIOTAPOP_BSR            4
83 #define VIOTAPOP_WEOF           5
84 #define VIOTAPOP_REW            6
85 #define VIOTAPOP_NOP            7
86 #define VIOTAPOP_EOM            8
87 #define VIOTAPOP_ERASE          9
88 #define VIOTAPOP_SETBLK        10
89 #define VIOTAPOP_SETDENSITY    11
90 #define VIOTAPOP_SETPOS        12
91 #define VIOTAPOP_GETPOS        13
92 #define VIOTAPOP_SETPART       14
93 #define VIOTAPOP_UNLOAD        15
94
95 enum viotaperc {
96         viotape_InvalidRange = 0x0601,
97         viotape_InvalidToken = 0x0602,
98         viotape_DMAError = 0x0603,
99         viotape_UseError = 0x0604,
100         viotape_ReleaseError = 0x0605,
101         viotape_InvalidTape = 0x0606,
102         viotape_InvalidOp = 0x0607,
103         viotape_TapeErr = 0x0608,
104
105         viotape_AllocTimedOut = 0x0640,
106         viotape_BOTEnc = 0x0641,
107         viotape_BlankTape = 0x0642,
108         viotape_BufferEmpty = 0x0643,
109         viotape_CleanCartFound = 0x0644,
110         viotape_CmdNotAllowed = 0x0645,
111         viotape_CmdNotSupported = 0x0646,
112         viotape_DataCheck = 0x0647,
113         viotape_DecompressErr = 0x0648,
114         viotape_DeviceTimeout = 0x0649,
115         viotape_DeviceUnavail = 0x064a,
116         viotape_DeviceBusy = 0x064b,
117         viotape_EndOfMedia = 0x064c,
118         viotape_EndOfTape = 0x064d,
119         viotape_EquipCheck = 0x064e,
120         viotape_InsufficientRs = 0x064f,
121         viotape_InvalidLogBlk = 0x0650,
122         viotape_LengthError = 0x0651,
123         viotape_LibDoorOpen = 0x0652,
124         viotape_LoadFailure = 0x0653,
125         viotape_NotCapable = 0x0654,
126         viotape_NotOperational = 0x0655,
127         viotape_NotReady = 0x0656,
128         viotape_OpCancelled = 0x0657,
129         viotape_PhyLinkErr = 0x0658,
130         viotape_RdyNotBOT = 0x0659,
131         viotape_TapeMark = 0x065a,
132         viotape_WriteProt = 0x065b
133 };
134
135 static const struct vio_error_entry viotape_err_table[] = {
136         { viotape_InvalidRange, EIO, "Internal error" },
137         { viotape_InvalidToken, EIO, "Internal error" },
138         { viotape_DMAError, EIO, "DMA error" },
139         { viotape_UseError, EIO, "Internal error" },
140         { viotape_ReleaseError, EIO, "Internal error" },
141         { viotape_InvalidTape, EIO, "Invalid tape device" },
142         { viotape_InvalidOp, EIO, "Invalid operation" },
143         { viotape_TapeErr, EIO, "Tape error" },
144         { viotape_AllocTimedOut, EBUSY, "Allocate timed out" },
145         { viotape_BOTEnc, EIO, "Beginning of tape encountered" },
146         { viotape_BlankTape, EIO, "Blank tape" },
147         { viotape_BufferEmpty, EIO, "Buffer empty" },
148         { viotape_CleanCartFound, ENOMEDIUM, "Cleaning cartridge found" },
149         { viotape_CmdNotAllowed, EIO, "Command not allowed" },
150         { viotape_CmdNotSupported, EIO, "Command not supported" },
151         { viotape_DataCheck, EIO, "Data check" },
152         { viotape_DecompressErr, EIO, "Decompression error" },
153         { viotape_DeviceTimeout, EBUSY, "Device timeout" },
154         { viotape_DeviceUnavail, EIO, "Device unavailable" },
155         { viotape_DeviceBusy, EBUSY, "Device busy" },
156         { viotape_EndOfMedia, ENOSPC, "End of media" },
157         { viotape_EndOfTape, ENOSPC, "End of tape" },
158         { viotape_EquipCheck, EIO, "Equipment check" },
159         { viotape_InsufficientRs, EOVERFLOW, "Insufficient tape resources" },
160         { viotape_InvalidLogBlk, EIO, "Invalid logical block location" },
161         { viotape_LengthError, EOVERFLOW, "Length error" },
162         { viotape_LibDoorOpen, EBUSY, "Door open" },
163         { viotape_LoadFailure, ENOMEDIUM, "Load failure" },
164         { viotape_NotCapable, EIO, "Not capable" },
165         { viotape_NotOperational, EIO, "Not operational" },
166         { viotape_NotReady, EIO, "Not ready" },
167         { viotape_OpCancelled, EIO, "Operation cancelled" },
168         { viotape_PhyLinkErr, EIO, "Physical link error" },
169         { viotape_RdyNotBOT, EIO, "Ready but not beginning of tape" },
170         { viotape_TapeMark, EIO, "Tape mark" },
171         { viotape_WriteProt, EROFS, "Write protection error" },
172         { 0, 0, NULL },
173 };
174
175 /* Maximum number of tapes we support */
176 #define VIOTAPE_MAX_TAPE        HVMAXARCHITECTEDVIRTUALTAPES
177 #define MAX_PARTITIONS          4
178
179 /* defines for current tape state */
180 #define VIOT_IDLE               0
181 #define VIOT_READING            1
182 #define VIOT_WRITING            2
183
184 /* Our info on the tapes */
185 static struct {
186         const char *rsrcname;
187         const char *type;
188         const char *model;
189 } viotape_unitinfo[VIOTAPE_MAX_TAPE];
190
191 static struct mtget viomtget[VIOTAPE_MAX_TAPE];
192
193 static struct class *tape_class;
194
195 static struct device *tape_device[VIOTAPE_MAX_TAPE];
196
197 /*
198  * maintain the current state of each tape (and partition)
199  * so that we know when to write EOF marks.
200  */
201 static struct {
202         unsigned char   cur_part;
203         unsigned char   part_stat_rwi[MAX_PARTITIONS];
204 } state[VIOTAPE_MAX_TAPE];
205
206 /* We single-thread */
207 static struct semaphore reqSem;
208
209 /*
210  * When we send a request, we use this struct to get the response back
211  * from the interrupt handler
212  */
213 struct op_struct {
214         void                    *buffer;
215         dma_addr_t              dmaaddr;
216         size_t                  count;
217         int                     rc;
218         int                     non_blocking;
219         struct completion       com;
220         struct device           *dev;
221         struct op_struct        *next;
222 };
223
224 static spinlock_t       op_struct_list_lock;
225 static struct op_struct *op_struct_list;
226
227 /* forward declaration to resolve interdependence */
228 static int chg_state(int index, unsigned char new_state, struct file *file);
229
230 /* procfs support */
231 static int proc_viotape_show(struct seq_file *m, void *v)
232 {
233         int i;
234
235         seq_printf(m, "viotape driver version " VIOTAPE_VERSION "\n");
236         for (i = 0; i < viotape_numdev; i++) {
237                 seq_printf(m, "viotape device %d is iSeries resource %10.10s"
238                                 "type %4.4s, model %3.3s\n",
239                                 i, viotape_unitinfo[i].rsrcname,
240                                 viotape_unitinfo[i].type,
241                                 viotape_unitinfo[i].model);
242         }
243         return 0;
244 }
245
246 static int proc_viotape_open(struct inode *inode, struct file *file)
247 {
248         return single_open(file, proc_viotape_show, NULL);
249 }
250
251 static const struct file_operations proc_viotape_operations = {
252         .open           = proc_viotape_open,
253         .read           = seq_read,
254         .llseek         = seq_lseek,
255         .release        = single_release,
256 };
257
258 /* Decode the device minor number into its parts */
259 void get_dev_info(struct inode *ino, struct viot_devinfo_struct *devi)
260 {
261         devi->devno = iminor(ino) & 0x1F;
262         devi->mode = (iminor(ino) & 0x60) >> 5;
263         /* if bit is set in the minor, do _not_ rewind automatically */
264         devi->rewind = (iminor(ino) & 0x80) == 0;
265 }
266
267 /* This is called only from the exit and init paths, so no need for locking */
268 static void clear_op_struct_pool(void)
269 {
270         while (op_struct_list) {
271                 struct op_struct *toFree = op_struct_list;
272                 op_struct_list = op_struct_list->next;
273                 kfree(toFree);
274         }
275 }
276
277 /* Likewise, this is only called from the init path */
278 static int add_op_structs(int structs)
279 {
280         int i;
281
282         for (i = 0; i < structs; ++i) {
283                 struct op_struct *new_struct =
284                         kmalloc(sizeof(*new_struct), GFP_KERNEL);
285                 if (!new_struct) {
286                         clear_op_struct_pool();
287                         return -ENOMEM;
288                 }
289                 new_struct->next = op_struct_list;
290                 op_struct_list = new_struct;
291         }
292         return 0;
293 }
294
295 /* Allocate an op structure from our pool */
296 static struct op_struct *get_op_struct(void)
297 {
298         struct op_struct *retval;
299         unsigned long flags;
300
301         spin_lock_irqsave(&op_struct_list_lock, flags);
302         retval = op_struct_list;
303         if (retval)
304                 op_struct_list = retval->next;
305         spin_unlock_irqrestore(&op_struct_list_lock, flags);
306         if (retval) {
307                 memset(retval, 0, sizeof(*retval));
308                 init_completion(&retval->com);
309         }
310
311         return retval;
312 }
313
314 /* Return an op structure to our pool */
315 static void free_op_struct(struct op_struct *op_struct)
316 {
317         unsigned long flags;
318
319         spin_lock_irqsave(&op_struct_list_lock, flags);
320         op_struct->next = op_struct_list;
321         op_struct_list = op_struct;
322         spin_unlock_irqrestore(&op_struct_list_lock, flags);
323 }
324
325 /* Map our tape return codes to errno values */
326 int tape_rc_to_errno(int tape_rc, char *operation, int tapeno)
327 {
328         const struct vio_error_entry *err;
329
330         if (tape_rc == 0)
331                 return 0;
332
333         err = vio_lookup_rc(viotape_err_table, tape_rc);
334         printk(VIOTAPE_KERN_WARN "error(%s) 0x%04x on Device %d (%-10s): %s\n",
335                         operation, tape_rc, tapeno,
336                         viotape_unitinfo[tapeno].rsrcname, err->msg);
337         return -err->errno;
338 }
339
340 /* Write */
341 static ssize_t viotap_write(struct file *file, const char *buf,
342                 size_t count, loff_t * ppos)
343 {
344         HvLpEvent_Rc hvrc;
345         unsigned short flags = file->f_flags;
346         int noblock = ((flags & O_NONBLOCK) != 0);
347         ssize_t ret;
348         struct viot_devinfo_struct devi;
349         struct op_struct *op = get_op_struct();
350
351         if (op == NULL)
352                 return -ENOMEM;
353
354         get_dev_info(file->f_path.dentry->d_inode, &devi);
355
356         /*
357          * We need to make sure we can send a request.  We use
358          * a semaphore to keep track of # requests in use.  If
359          * we are non-blocking, make sure we don't block on the
360          * semaphore
361          */
362         if (noblock) {
363                 if (down_trylock(&reqSem)) {
364                         ret = -EWOULDBLOCK;
365                         goto free_op;
366                 }
367         } else
368                 down(&reqSem);
369
370         /* Allocate a DMA buffer */
371         op->dev = tape_device[devi.devno];
372         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
373                         GFP_ATOMIC);
374
375         if (op->buffer == NULL) {
376                 printk(VIOTAPE_KERN_WARN
377                                 "error allocating dma buffer for len %ld\n",
378                                 count);
379                 ret = -EFAULT;
380                 goto up_sem;
381         }
382
383         /* Copy the data into the buffer */
384         if (copy_from_user(op->buffer, buf, count)) {
385                 printk(VIOTAPE_KERN_WARN "tape: error on copy from user\n");
386                 ret = -EFAULT;
387                 goto free_dma;
388         }
389
390         op->non_blocking = noblock;
391         init_completion(&op->com);
392         op->count = count;
393
394         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
395                         HvLpEvent_Type_VirtualIo,
396                         viomajorsubtype_tape | viotapewrite,
397                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
398                         viopath_sourceinst(viopath_hostLp),
399                         viopath_targetinst(viopath_hostLp),
400                         (u64)(unsigned long)op, VIOVERSION << 16,
401                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
402         if (hvrc != HvLpEvent_Rc_Good) {
403                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
404                                 (int)hvrc);
405                 ret = -EIO;
406                 goto free_dma;
407         }
408
409         if (noblock)
410                 return count;
411
412         wait_for_completion(&op->com);
413
414         if (op->rc)
415                 ret = tape_rc_to_errno(op->rc, "write", devi.devno);
416         else {
417                 chg_state(devi.devno, VIOT_WRITING, file);
418                 ret = op->count;
419         }
420
421 free_dma:
422         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
423 up_sem:
424         up(&reqSem);
425 free_op:
426         free_op_struct(op);
427         return ret;
428 }
429
430 /* read */
431 static ssize_t viotap_read(struct file *file, char *buf, size_t count,
432                 loff_t *ptr)
433 {
434         HvLpEvent_Rc hvrc;
435         unsigned short flags = file->f_flags;
436         struct op_struct *op = get_op_struct();
437         int noblock = ((flags & O_NONBLOCK) != 0);
438         ssize_t ret;
439         struct viot_devinfo_struct devi;
440
441         if (op == NULL)
442                 return -ENOMEM;
443
444         get_dev_info(file->f_path.dentry->d_inode, &devi);
445
446         /*
447          * We need to make sure we can send a request.  We use
448          * a semaphore to keep track of # requests in use.  If
449          * we are non-blocking, make sure we don't block on the
450          * semaphore
451          */
452         if (noblock) {
453                 if (down_trylock(&reqSem)) {
454                         ret = -EWOULDBLOCK;
455                         goto free_op;
456                 }
457         } else
458                 down(&reqSem);
459
460         chg_state(devi.devno, VIOT_READING, file);
461
462         /* Allocate a DMA buffer */
463         op->dev = tape_device[devi.devno];
464         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
465                         GFP_ATOMIC);
466         if (op->buffer == NULL) {
467                 ret = -EFAULT;
468                 goto up_sem;
469         }
470
471         op->count = count;
472         init_completion(&op->com);
473
474         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
475                         HvLpEvent_Type_VirtualIo,
476                         viomajorsubtype_tape | viotaperead,
477                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
478                         viopath_sourceinst(viopath_hostLp),
479                         viopath_targetinst(viopath_hostLp),
480                         (u64)(unsigned long)op, VIOVERSION << 16,
481                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
482         if (hvrc != HvLpEvent_Rc_Good) {
483                 printk(VIOTAPE_KERN_WARN "tape hv error on op %d\n",
484                                 (int)hvrc);
485                 ret = -EIO;
486                 goto free_dma;
487         }
488
489         wait_for_completion(&op->com);
490
491         if (op->rc)
492                 ret = tape_rc_to_errno(op->rc, "read", devi.devno);
493         else {
494                 ret = op->count;
495                 if (ret && copy_to_user(buf, op->buffer, ret)) {
496                         printk(VIOTAPE_KERN_WARN "error on copy_to_user\n");
497                         ret = -EFAULT;
498                 }
499         }
500
501 free_dma:
502         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
503 up_sem:
504         up(&reqSem);
505 free_op:
506         free_op_struct(op);
507         return ret;
508 }
509
510 /* ioctl */
511 static int viotap_ioctl(struct inode *inode, struct file *file,
512                 unsigned int cmd, unsigned long arg)
513 {
514         HvLpEvent_Rc hvrc;
515         int ret;
516         struct viot_devinfo_struct devi;
517         struct mtop mtc;
518         u32 myOp;
519         struct op_struct *op = get_op_struct();
520
521         if (op == NULL)
522                 return -ENOMEM;
523
524         get_dev_info(file->f_path.dentry->d_inode, &devi);
525
526         down(&reqSem);
527
528         ret = -EINVAL;
529
530         switch (cmd) {
531         case MTIOCTOP:
532                 ret = -EFAULT;
533                 /*
534                  * inode is null if and only if we (the kernel)
535                  * made the request
536                  */
537                 if (inode == NULL)
538                         memcpy(&mtc, (void *) arg, sizeof(struct mtop));
539                 else if (copy_from_user((char *)&mtc, (char *)arg,
540                                         sizeof(struct mtop)))
541                         goto free_op;
542
543                 ret = -EIO;
544                 switch (mtc.mt_op) {
545                 case MTRESET:
546                         myOp = VIOTAPOP_RESET;
547                         break;
548                 case MTFSF:
549                         myOp = VIOTAPOP_FSF;
550                         break;
551                 case MTBSF:
552                         myOp = VIOTAPOP_BSF;
553                         break;
554                 case MTFSR:
555                         myOp = VIOTAPOP_FSR;
556                         break;
557                 case MTBSR:
558                         myOp = VIOTAPOP_BSR;
559                         break;
560                 case MTWEOF:
561                         myOp = VIOTAPOP_WEOF;
562                         break;
563                 case MTREW:
564                         myOp = VIOTAPOP_REW;
565                         break;
566                 case MTNOP:
567                         myOp = VIOTAPOP_NOP;
568                         break;
569                 case MTEOM:
570                         myOp = VIOTAPOP_EOM;
571                         break;
572                 case MTERASE:
573                         myOp = VIOTAPOP_ERASE;
574                         break;
575                 case MTSETBLK:
576                         myOp = VIOTAPOP_SETBLK;
577                         break;
578                 case MTSETDENSITY:
579                         myOp = VIOTAPOP_SETDENSITY;
580                         break;
581                 case MTTELL:
582                         myOp = VIOTAPOP_GETPOS;
583                         break;
584                 case MTSEEK:
585                         myOp = VIOTAPOP_SETPOS;
586                         break;
587                 case MTSETPART:
588                         myOp = VIOTAPOP_SETPART;
589                         break;
590                 case MTOFFL:
591                         myOp = VIOTAPOP_UNLOAD;
592                         break;
593                 default:
594                         printk(VIOTAPE_KERN_WARN "MTIOCTOP called "
595                                         "with invalid op 0x%x\n", mtc.mt_op);
596                         goto free_op;
597                 }
598
599                 /*
600                  * if we moved the head, we are no longer
601                  * reading or writing
602                  */
603                 switch (mtc.mt_op) {
604                 case MTFSF:
605                 case MTBSF:
606                 case MTFSR:
607                 case MTBSR:
608                 case MTTELL:
609                 case MTSEEK:
610                 case MTREW:
611                         chg_state(devi.devno, VIOT_IDLE, file);
612                 }
613
614                 init_completion(&op->com);
615                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
616                                 HvLpEvent_Type_VirtualIo,
617                                 viomajorsubtype_tape | viotapeop,
618                                 HvLpEvent_AckInd_DoAck,
619                                 HvLpEvent_AckType_ImmediateAck,
620                                 viopath_sourceinst(viopath_hostLp),
621                                 viopath_targetinst(viopath_hostLp),
622                                 (u64)(unsigned long)op,
623                                 VIOVERSION << 16,
624                                 ((u64)devi.devno << 48), 0,
625                                 (((u64)myOp) << 32) | mtc.mt_count, 0);
626                 if (hvrc != HvLpEvent_Rc_Good) {
627                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
628                                         (int)hvrc);
629                         goto free_op;
630                 }
631                 wait_for_completion(&op->com);
632                 ret = tape_rc_to_errno(op->rc, "tape operation", devi.devno);
633                 goto free_op;
634
635         case MTIOCGET:
636                 ret = -EIO;
637                 init_completion(&op->com);
638                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
639                                 HvLpEvent_Type_VirtualIo,
640                                 viomajorsubtype_tape | viotapegetstatus,
641                                 HvLpEvent_AckInd_DoAck,
642                                 HvLpEvent_AckType_ImmediateAck,
643                                 viopath_sourceinst(viopath_hostLp),
644                                 viopath_targetinst(viopath_hostLp),
645                                 (u64)(unsigned long)op, VIOVERSION << 16,
646                                 ((u64)devi.devno << 48), 0, 0, 0);
647                 if (hvrc != HvLpEvent_Rc_Good) {
648                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
649                                         (int)hvrc);
650                         goto free_op;
651                 }
652                 wait_for_completion(&op->com);
653
654                 /* Operation is complete - grab the error code */
655                 ret = tape_rc_to_errno(op->rc, "get status", devi.devno);
656                 free_op_struct(op);
657                 up(&reqSem);
658
659                 if ((ret == 0) && copy_to_user((void *)arg,
660                                         &viomtget[devi.devno],
661                                         sizeof(viomtget[0])))
662                         ret = -EFAULT;
663                 return ret;
664         case MTIOCPOS:
665                 printk(VIOTAPE_KERN_WARN "Got an (unsupported) MTIOCPOS\n");
666                 break;
667         default:
668                 printk(VIOTAPE_KERN_WARN "got an unsupported ioctl 0x%0x\n",
669                                 cmd);
670                 break;
671         }
672
673 free_op:
674         free_op_struct(op);
675         up(&reqSem);
676         return ret;
677 }
678
679 static int viotap_open(struct inode *inode, struct file *file)
680 {
681         HvLpEvent_Rc hvrc;
682         struct viot_devinfo_struct devi;
683         int ret;
684         struct op_struct *op = get_op_struct();
685
686         if (op == NULL)
687                 return -ENOMEM;
688
689         get_dev_info(file->f_path.dentry->d_inode, &devi);
690
691         /* Note: We currently only support one mode! */
692         if ((devi.devno >= viotape_numdev) || (devi.mode)) {
693                 ret = -ENODEV;
694                 goto free_op;
695         }
696
697         init_completion(&op->com);
698
699         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
700                         HvLpEvent_Type_VirtualIo,
701                         viomajorsubtype_tape | viotapeopen,
702                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
703                         viopath_sourceinst(viopath_hostLp),
704                         viopath_targetinst(viopath_hostLp),
705                         (u64)(unsigned long)op, VIOVERSION << 16,
706                         ((u64)devi.devno << 48), 0, 0, 0);
707         if (hvrc != 0) {
708                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
709                                 (int) hvrc);
710                 ret = -EIO;
711                 goto free_op;
712         }
713
714         wait_for_completion(&op->com);
715         ret = tape_rc_to_errno(op->rc, "open", devi.devno);
716
717 free_op:
718         free_op_struct(op);
719         return ret;
720 }
721
722
723 static int viotap_release(struct inode *inode, struct file *file)
724 {
725         HvLpEvent_Rc hvrc;
726         struct viot_devinfo_struct devi;
727         int ret = 0;
728         struct op_struct *op = get_op_struct();
729
730         if (op == NULL)
731                 return -ENOMEM;
732         init_completion(&op->com);
733
734         get_dev_info(file->f_path.dentry->d_inode, &devi);
735
736         if (devi.devno >= viotape_numdev) {
737                 ret = -ENODEV;
738                 goto free_op;
739         }
740
741         chg_state(devi.devno, VIOT_IDLE, file);
742
743         if (devi.rewind) {
744                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
745                                 HvLpEvent_Type_VirtualIo,
746                                 viomajorsubtype_tape | viotapeop,
747                                 HvLpEvent_AckInd_DoAck,
748                                 HvLpEvent_AckType_ImmediateAck,
749                                 viopath_sourceinst(viopath_hostLp),
750                                 viopath_targetinst(viopath_hostLp),
751                                 (u64)(unsigned long)op, VIOVERSION << 16,
752                                 ((u64)devi.devno << 48), 0,
753                                 ((u64)VIOTAPOP_REW) << 32, 0);
754                 wait_for_completion(&op->com);
755
756                 tape_rc_to_errno(op->rc, "rewind", devi.devno);
757         }
758
759         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
760                         HvLpEvent_Type_VirtualIo,
761                         viomajorsubtype_tape | viotapeclose,
762                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
763                         viopath_sourceinst(viopath_hostLp),
764                         viopath_targetinst(viopath_hostLp),
765                         (u64)(unsigned long)op, VIOVERSION << 16,
766                         ((u64)devi.devno << 48), 0, 0, 0);
767         if (hvrc != 0) {
768                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
769                                 (int) hvrc);
770                 ret = -EIO;
771                 goto free_op;
772         }
773
774         wait_for_completion(&op->com);
775
776         if (op->rc)
777                 printk(VIOTAPE_KERN_WARN "close failed\n");
778
779 free_op:
780         free_op_struct(op);
781         return ret;
782 }
783
784 const struct file_operations viotap_fops = {
785         .owner =        THIS_MODULE,
786         .read =         viotap_read,
787         .write =        viotap_write,
788         .ioctl =        viotap_ioctl,
789         .open =         viotap_open,
790         .release =      viotap_release,
791 };
792
793 /* Handle interrupt events for tape */
794 static void vioHandleTapeEvent(struct HvLpEvent *event)
795 {
796         int tapeminor;
797         struct op_struct *op;
798         struct viotapelpevent *tevent = (struct viotapelpevent *)event;
799
800         if (event == NULL) {
801                 /* Notification that a partition went away! */
802                 if (!viopath_isactive(viopath_hostLp)) {
803                         /* TODO! Clean up */
804                 }
805                 return;
806         }
807
808         tapeminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
809         op = (struct op_struct *)event->xCorrelationToken;
810         switch (tapeminor) {
811         case viotapeopen:
812         case viotapeclose:
813                 op->rc = tevent->sub_type_result;
814                 complete(&op->com);
815                 break;
816         case viotaperead:
817                 op->rc = tevent->sub_type_result;
818                 op->count = tevent->len;
819                 complete(&op->com);
820                 break;
821         case viotapewrite:
822                 if (op->non_blocking) {
823                         dma_free_coherent(op->dev, op->count,
824                                         op->buffer, op->dmaaddr);
825                         free_op_struct(op);
826                         up(&reqSem);
827                 } else {
828                         op->rc = tevent->sub_type_result;
829                         op->count = tevent->len;
830                         complete(&op->com);
831                 }
832                 break;
833         case viotapeop:
834         case viotapegetpos:
835         case viotapesetpos:
836         case viotapegetstatus:
837                 if (op) {
838                         op->count = tevent->u.op.count;
839                         op->rc = tevent->sub_type_result;
840                         if (!op->non_blocking)
841                                 complete(&op->com);
842                 }
843                 break;
844         default:
845                 printk(VIOTAPE_KERN_WARN "weird ack\n");
846         }
847 }
848
849 static int viotape_probe(struct vio_dev *vdev, const struct vio_device_id *id)
850 {
851         int i = vdev->unit_address;
852         int j;
853         struct device_node *node = vdev->dev.archdata.of_node;
854
855         if (i > VIOTAPE_MAX_TAPE)
856                 return -ENODEV;
857         if (!node)
858                 return -ENODEV;
859
860         if (i >= viotape_numdev)
861                 viotape_numdev = i + 1;
862
863         tape_device[i] = &vdev->dev;
864         viotape_unitinfo[i].rsrcname = of_get_property(node,
865                                         "linux,vio_rsrcname", NULL);
866         viotape_unitinfo[i].type = of_get_property(node, "linux,vio_type",
867                                         NULL);
868         viotape_unitinfo[i].model = of_get_property(node, "linux,vio_model",
869                                         NULL);
870
871         state[i].cur_part = 0;
872         for (j = 0; j < MAX_PARTITIONS; ++j)
873                 state[i].part_stat_rwi[j] = VIOT_IDLE;
874         device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i),
875                         "iseries!vt%d", i);
876         device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i | 0x80),
877                         "iseries!nvt%d", i);
878         printk(VIOTAPE_KERN_INFO "tape iseries/vt%d is iSeries "
879                         "resource %10.10s type %4.4s, model %3.3s\n",
880                         i, viotape_unitinfo[i].rsrcname,
881                         viotape_unitinfo[i].type, viotape_unitinfo[i].model);
882         return 0;
883 }
884
885 static int viotape_remove(struct vio_dev *vdev)
886 {
887         int i = vdev->unit_address;
888
889         device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i | 0x80));
890         device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i));
891         return 0;
892 }
893
894 /**
895  * viotape_device_table: Used by vio.c to match devices that we
896  * support.
897  */
898 static struct vio_device_id viotape_device_table[] __devinitdata = {
899         { "byte", "IBM,iSeries-viotape" },
900         { "", "" }
901 };
902 MODULE_DEVICE_TABLE(vio, viotape_device_table);
903
904 static struct vio_driver viotape_driver = {
905         .id_table = viotape_device_table,
906         .probe = viotape_probe,
907         .remove = viotape_remove,
908         .driver = {
909                 .name = "viotape",
910                 .owner = THIS_MODULE,
911         }
912 };
913
914
915 int __init viotap_init(void)
916 {
917         int ret;
918         struct proc_dir_entry *e;
919
920         if (!firmware_has_feature(FW_FEATURE_ISERIES))
921                 return -ENODEV;
922
923         op_struct_list = NULL;
924         if ((ret = add_op_structs(VIOTAPE_MAXREQ)) < 0) {
925                 printk(VIOTAPE_KERN_WARN "couldn't allocate op structs\n");
926                 return ret;
927         }
928         spin_lock_init(&op_struct_list_lock);
929
930         sema_init(&reqSem, VIOTAPE_MAXREQ);
931
932         if (viopath_hostLp == HvLpIndexInvalid) {
933                 vio_set_hostlp();
934                 if (viopath_hostLp == HvLpIndexInvalid) {
935                         ret = -ENODEV;
936                         goto clear_op;
937                 }
938         }
939
940         ret = viopath_open(viopath_hostLp, viomajorsubtype_tape,
941                         VIOTAPE_MAXREQ + 2);
942         if (ret) {
943                 printk(VIOTAPE_KERN_WARN
944                                 "error on viopath_open to hostlp %d\n", ret);
945                 ret = -EIO;
946                 goto clear_op;
947         }
948
949         printk(VIOTAPE_KERN_INFO "vers " VIOTAPE_VERSION
950                         ", hosting partition %d\n", viopath_hostLp);
951
952         vio_setHandler(viomajorsubtype_tape, vioHandleTapeEvent);
953
954         ret = register_chrdev(VIOTAPE_MAJOR, "viotape", &viotap_fops);
955         if (ret < 0) {
956                 printk(VIOTAPE_KERN_WARN "Error registering viotape device\n");
957                 goto clear_handler;
958         }
959
960         tape_class = class_create(THIS_MODULE, "tape");
961         if (IS_ERR(tape_class)) {
962                 printk(VIOTAPE_KERN_WARN "Unable to allocat class\n");
963                 ret = PTR_ERR(tape_class);
964                 goto unreg_chrdev;
965         }
966
967         ret = vio_register_driver(&viotape_driver);
968         if (ret)
969                 goto unreg_class;
970
971         e = create_proc_entry("iSeries/viotape", S_IFREG|S_IRUGO, NULL);
972         if (e) {
973                 e->owner = THIS_MODULE;
974                 e->proc_fops = &proc_viotape_operations;
975         }
976
977         return 0;
978
979 unreg_class:
980         class_destroy(tape_class);
981 unreg_chrdev:
982         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
983 clear_handler:
984         vio_clearHandler(viomajorsubtype_tape);
985         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
986 clear_op:
987         clear_op_struct_pool();
988         return ret;
989 }
990
991 /* Give a new state to the tape object */
992 static int chg_state(int index, unsigned char new_state, struct file *file)
993 {
994         unsigned char *cur_state =
995             &state[index].part_stat_rwi[state[index].cur_part];
996         int rc = 0;
997
998         /* if the same state, don't bother */
999         if (*cur_state == new_state)
1000                 return 0;
1001
1002         /* write an EOF if changing from writing to some other state */
1003         if (*cur_state == VIOT_WRITING) {
1004                 struct mtop write_eof = { MTWEOF, 1 };
1005
1006                 rc = viotap_ioctl(NULL, file, MTIOCTOP,
1007                                   (unsigned long)&write_eof);
1008         }
1009         *cur_state = new_state;
1010         return rc;
1011 }
1012
1013 /* Cleanup */
1014 static void __exit viotap_exit(void)
1015 {
1016         remove_proc_entry("iSeries/viotape", NULL);
1017         vio_unregister_driver(&viotape_driver);
1018         class_destroy(tape_class);
1019         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1020         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1021         vio_clearHandler(viomajorsubtype_tape);
1022         clear_op_struct_pool();
1023 }
1024
1025 MODULE_LICENSE("GPL");
1026 module_init(viotap_init);
1027 module_exit(viotap_exit);