drivers/s390/scsi/zfcp_cfdc.c

   1 /*
   2  * zfcp device driver
   3  *
   4  * Userspace interface for accessing the
   5  * Access Control Lists / Control File Data Channel
   6  *
   7  * Copyright IBM Corporation 2008, 2009
   8  */
   9
  10 #define KMSG_COMPONENT "zfcp"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/types.h>
  14 #include <linux/miscdevice.h>
  15 #include <asm/ccwdev.h>
  16 #include "zfcp_def.h"
  17 #include "zfcp_ext.h"
  18 #include "zfcp_fsf.h"
  19
  20 #define ZFCP_CFDC_CMND_DOWNLOAD_NORMAL          0x00010001
  21 #define ZFCP_CFDC_CMND_DOWNLOAD_FORCE           0x00010101
  22 #define ZFCP_CFDC_CMND_FULL_ACCESS              0x00000201
  23 #define ZFCP_CFDC_CMND_RESTRICTED_ACCESS        0x00000401
  24 #define ZFCP_CFDC_CMND_UPLOAD                   0x00010002
  25
  26 #define ZFCP_CFDC_DOWNLOAD                      0x00000001
  27 #define ZFCP_CFDC_UPLOAD                        0x00000002
  28 #define ZFCP_CFDC_WITH_CONTROL_FILE             0x00010000
  29
  30 #define ZFCP_CFDC_IOC_MAGIC                     0xDD
  31 #define ZFCP_CFDC_IOC \
  32         _IOWR(ZFCP_CFDC_IOC_MAGIC, 0, struct zfcp_cfdc_data)
  33
  34 /**
  35  * struct zfcp_cfdc_data - data for ioctl cfdc interface
  36  * @signature: request signature
  37  * @devno: FCP adapter device number
  38  * @command: command code
  39  * @fsf_status: returns status of FSF command to userspace
  40  * @fsf_status_qual: returned to userspace
  41  * @payloads: access conflicts list
  42  * @control_file: access control table
  43  */
  44 struct zfcp_cfdc_data {
  45         u32 signature;
  46         u32 devno;
  47         u32 command;
  48         u32 fsf_status;
  49         u8  fsf_status_qual[FSF_STATUS_QUALIFIER_SIZE];
  50         u8  payloads[256];
  51         u8  control_file[0];
  52 };
  53
  54 static int zfcp_cfdc_copy_from_user(struct scatterlist *sg,
  55                                     void __user *user_buffer)
  56 {
  57         unsigned int length;
  58         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  59
  60         while (size) {
  61                 length = min((unsigned int)size, sg->length);
  62                 if (copy_from_user(sg_virt(sg++), user_buffer, length))
  63                         return -EFAULT;
  64                 user_buffer += length;
  65                 size -= length;
  66         }
  67         return 0;
  68 }
  69
  70 static int zfcp_cfdc_copy_to_user(void __user  *user_buffer,
  71                                   struct scatterlist *sg)
  72 {
  73         unsigned int length;
  74         unsigned int size = ZFCP_CFDC_MAX_SIZE;
  75
  76         while (size) {
  77                 length = min((unsigned int) size, sg->length);
  78                 if (copy_to_user(user_buffer, sg_virt(sg++), length))
  79                         return -EFAULT;
  80                 user_buffer += length;
  81                 size -= length;
  82         }
  83         return 0;
  84 }
  85
  86 static struct zfcp_adapter *zfcp_cfdc_get_adapter(u32 devno)
  87 {
  88         char busid[9];
  89         snprintf(busid, sizeof(busid), "0.0.%04x", devno);
  90         return zfcp_get_adapter_by_busid(busid);
  91 }
  92
  93 static int zfcp_cfdc_set_fsf(struct zfcp_fsf_cfdc *fsf_cfdc, int command)
  94 {
  95         switch (command) {
  96         case ZFCP_CFDC_CMND_DOWNLOAD_NORMAL:
  97                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
  98                 fsf_cfdc->option = FSF_CFDC_OPTION_NORMAL_MODE;
  99                 break;
 100         case ZFCP_CFDC_CMND_DOWNLOAD_FORCE:
 101                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 102                 fsf_cfdc->option = FSF_CFDC_OPTION_FORCE;
 103                 break;
 104         case ZFCP_CFDC_CMND_FULL_ACCESS:
 105                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 106                 fsf_cfdc->option = FSF_CFDC_OPTION_FULL_ACCESS;
 107                 break;
 108         case ZFCP_CFDC_CMND_RESTRICTED_ACCESS:
 109                 fsf_cfdc->command = FSF_QTCB_DOWNLOAD_CONTROL_FILE;
 110                 fsf_cfdc->option = FSF_CFDC_OPTION_RESTRICTED_ACCESS;
 111                 break;
 112         case ZFCP_CFDC_CMND_UPLOAD:
 113                 fsf_cfdc->command = FSF_QTCB_UPLOAD_CONTROL_FILE;
 114                 fsf_cfdc->option = 0;
 115                 break;
 116         default:
 117                 return -EINVAL;
 118         }
 119
 120         return 0;
 121 }
 122
 123 static int zfcp_cfdc_sg_setup(int command, struct scatterlist *sg,
 124                               u8 __user *control_file)
 125 {
 126         int retval;
 127         retval = zfcp_sg_setup_table(sg, ZFCP_CFDC_PAGES);
 128         if (retval)
 129                 return retval;
 130
 131         sg[ZFCP_CFDC_PAGES - 1].length = ZFCP_CFDC_MAX_SIZE % PAGE_SIZE;
 132
 133         if (command & ZFCP_CFDC_WITH_CONTROL_FILE &&
 134             command & ZFCP_CFDC_DOWNLOAD) {
 135                 retval = zfcp_cfdc_copy_from_user(sg, control_file);
 136                 if (retval) {
 137                         zfcp_sg_free_table(sg, ZFCP_CFDC_PAGES);
 138                         return -EFAULT;
 139                 }
 140         }
 141
 142         return 0;
 143 }
 144
 145 static void zfcp_cfdc_req_to_sense(struct zfcp_cfdc_data *data,
 146                                    struct zfcp_fsf_req *req)
 147 {
 148         data->fsf_status = req->qtcb->header.fsf_status;
 149         memcpy(&data->fsf_status_qual, &req->qtcb->header.fsf_status_qual,
 150                sizeof(union fsf_status_qual));
 151         memcpy(&data->payloads, &req->qtcb->bottom.support.els,
 152                sizeof(req->qtcb->bottom.support.els));
 153 }
 154
 155 static long zfcp_cfdc_dev_ioctl(struct file *file, unsigned int command,
 156                                 unsigned long buffer)
 157 {
 158         struct zfcp_cfdc_data *data;
 159         struct zfcp_cfdc_data __user *data_user;
 160         struct zfcp_adapter *adapter;
 161         struct zfcp_fsf_req *req;
 162         struct zfcp_fsf_cfdc *fsf_cfdc;
 163         int retval;
 164
 165         if (command != ZFCP_CFDC_IOC)
 166                 return -ENOTTY;
 167
 168         data_user = (void __user *) buffer;
 169         if (!data_user)
 170                 return -EINVAL;
 171
 172         fsf_cfdc = kmalloc(sizeof(struct zfcp_fsf_cfdc), GFP_KERNEL);
 173         if (!fsf_cfdc)
 174                 return -ENOMEM;
 175
 176         data = kmalloc(sizeof(struct zfcp_cfdc_data), GFP_KERNEL);
 177         if (!data) {
 178                 retval = -ENOMEM;
 179                 goto no_mem_sense;
 180         }
 181
 182         retval = copy_from_user(data, data_user, sizeof(*data));
 183         if (retval) {
 184                 retval = -EFAULT;
 185                 goto free_buffer;
 186         }
 187
 188         if (data->signature != 0xCFDCACDF) {
 189                 retval = -EINVAL;
 190                 goto free_buffer;
 191         }
 192
 193         retval = zfcp_cfdc_set_fsf(fsf_cfdc, data->command);
 194
 195         adapter = zfcp_cfdc_get_adapter(data->devno);
 196         if (!adapter) {
 197                 retval = -ENXIO;
 198                 goto free_buffer;
 199         }
 200         zfcp_adapter_get(adapter);
 201
 202         retval = zfcp_cfdc_sg_setup(data->command, fsf_cfdc->sg,
 203                                     data_user->control_file);
 204         if (retval)
 205                 goto adapter_put;
 206         req = zfcp_fsf_control_file(adapter, fsf_cfdc);
 207         if (IS_ERR(req)) {
 208                 retval = PTR_ERR(req);
 209                 goto free_sg;
 210         }
 211
 212         if (req->status & ZFCP_STATUS_FSFREQ_ERROR) {
 213                 retval = -ENXIO;
 214                 goto free_fsf;
 215         }
 216
 217         zfcp_cfdc_req_to_sense(data, req);
 218         retval = copy_to_user(data_user, data, sizeof(*data_user));
 219         if (retval) {
 220                 retval = -EFAULT;
 221                 goto free_fsf;
 222         }
 223
 224         if (data->command & ZFCP_CFDC_UPLOAD)
 225                 retval = zfcp_cfdc_copy_to_user(&data_user->control_file,
 226                                                 fsf_cfdc->sg);
 227
 228  free_fsf:
 229         zfcp_fsf_req_free(req);
 230  free_sg:
 231         zfcp_sg_free_table(fsf_cfdc->sg, ZFCP_CFDC_PAGES);
 232  adapter_put:
 233         zfcp_adapter_put(adapter);
 234  free_buffer:
 235         kfree(data);
 236  no_mem_sense:
 237         kfree(fsf_cfdc);
 238         return retval;
 239 }
 240
 241 static const struct file_operations zfcp_cfdc_fops = {
 242         .unlocked_ioctl = zfcp_cfdc_dev_ioctl,
 243 #ifdef CONFIG_COMPAT
 244         .compat_ioctl = zfcp_cfdc_dev_ioctl
 245 #endif
 246 };
 247
 248 struct miscdevice zfcp_cfdc_misc = {
 249         .minor = MISC_DYNAMIC_MINOR,
 250         .name = "zfcp_cfdc",
 251         .fops = &zfcp_cfdc_fops,
 252 };