drivers/staging/keucr/scsiglue.c

   1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   2
   3 #include <linux/slab.h>
   4 #include <linux/module.h>
   5 #include <linux/mutex.h>
   6
   7 #include <scsi/scsi.h>
   8 #include <scsi/scsi_cmnd.h>
   9 #include <scsi/scsi_devinfo.h>
  10 #include <scsi/scsi_device.h>
  11 #include <scsi/scsi_eh.h>
  12
  13 #include "usb.h"
  14 #include "scsiglue.h"
  15 #include "transport.h"
  16
  17 /* Host functions */
  18 /*
  19  * host_info()
  20  */
  21 static const char *host_info(struct Scsi_Host *host)
  22 {
  23         /* pr_info("scsiglue --- host_info\n"); */
  24         return "SCSI emulation for USB Mass Storage devices";
  25 }
  26
  27 /*
  28  * slave_alloc()
  29  */
  30 static int slave_alloc(struct scsi_device *sdev)
  31 {
  32         struct us_data *us = host_to_us(sdev->host);
  33
  34         /* pr_info("scsiglue --- slave_alloc\n"); */
  35         sdev->inquiry_len = 36;
  36
  37         blk_queue_update_dma_alignment(sdev->request_queue, (512 - 1));
  38
  39         if (us->subclass == USB_SC_UFI)
  40                 sdev->sdev_target->pdt_1f_for_no_lun = 1;
  41
  42         return 0;
  43 }
  44
  45 /*
  46  * slave_configure()
  47  */
  48 static int slave_configure(struct scsi_device *sdev)
  49 {
  50         struct us_data *us = host_to_us(sdev->host);
  51
  52         /* pr_info("scsiglue --- slave_configure\n"); */
  53         if (us->fflags & (US_FL_MAX_SECTORS_64 | US_FL_MAX_SECTORS_MIN)) {
  54                 unsigned int max_sectors = 64;
  55
  56                 if (us->fflags & US_FL_MAX_SECTORS_MIN)
  57                         max_sectors = PAGE_CACHE_SIZE >> 9;
  58                 if (queue_max_sectors(sdev->request_queue) > max_sectors)
  59                         blk_queue_max_hw_sectors(sdev->request_queue,
  60                                               max_sectors);
  61         }
  62
  63         if (sdev->type == TYPE_DISK) {
  64                 if (us->subclass != USB_SC_SCSI &&
  65                         us->subclass != USB_SC_CYP_ATACB)
  66                         sdev->use_10_for_ms = 1;
  67                 sdev->use_192_bytes_for_3f = 1;
  68                 if (us->fflags & US_FL_NO_WP_DETECT)
  69                         sdev->skip_ms_page_3f = 1;
  70                 sdev->skip_ms_page_8 = 1;
  71                 if (us->fflags & US_FL_FIX_CAPACITY)
  72                         sdev->fix_capacity = 1;
  73                 if (us->fflags & US_FL_CAPACITY_HEURISTICS)
  74                         sdev->guess_capacity = 1;
  75                 if (sdev->scsi_level > SCSI_2)
  76                         sdev->sdev_target->scsi_level = sdev->scsi_level = SCSI_2;
  77                 sdev->retry_hwerror = 1;
  78                 sdev->allow_restart = 1;
  79                 sdev->last_sector_bug = 1;
  80         } else {
  81                 sdev->use_10_for_ms = 1;
  82         }
  83
  84         if ((us->protocol == USB_PR_CB || us->protocol == USB_PR_CBI) &&
  85                                         sdev->scsi_level == SCSI_UNKNOWN)
  86                 us->max_lun = 0;
  87
  88         if (us->fflags & US_FL_NOT_LOCKABLE)
  89                 sdev->lockable = 0;
  90
  91         return 0;
  92 }
  93
  94 /* This is always called with scsi_lock(host) held */
  95 /*
  96  * queuecommand()
  97  */
  98 static int queuecommand_lck(struct scsi_cmnd *srb,
  99                                 void (*done)(struct scsi_cmnd *))
 100 {
 101         struct us_data *us = host_to_us(srb->device->host);
 102
 103         /* pr_info("scsiglue --- queuecommand\n"); */
 104
 105         /* check for state-transition errors */
 106         if (us->srb != NULL) {
 107                 /* pr_info("Error in %s: us->srb = %p\n"
 108                                  __FUNCTION__, us->srb); */
 109                 return SCSI_MLQUEUE_HOST_BUSY;
 110         }
 111
 112         /* fail the command if we are disconnecting */
 113         if (test_bit(US_FLIDX_DISCONNECTING, &us->dflags)) {
 114                 pr_info("Fail command during disconnect\n");
 115                 srb->result = DID_NO_CONNECT << 16;
 116                 done(srb);
 117                 return 0;
 118         }
 119
 120         /* enqueue the command and wake up the control thread */
 121         srb->scsi_done = done;
 122         us->srb = srb;
 123         complete(&us->cmnd_ready);
 124
 125         return 0;
 126 }
 127
 128 static DEF_SCSI_QCMD(queuecommand)
 129
 130 /***********************************************************************
 131  * Error handling functions
 132  ***********************************************************************/
 133
 134 /* Command timeout and abort */
 135 /*
 136  * command_abort()
 137  */
 138 static int command_abort(struct scsi_cmnd *srb)
 139 {
 140         struct us_data *us = host_to_us(srb->device->host);
 141
 142         /* pr_info("scsiglue --- command_abort\n"); */
 143
 144         scsi_lock(us_to_host(us));
 145         if (us->srb != srb) {
 146                 scsi_unlock(us_to_host(us));
 147                 printk ("-- nothing to abort\n");
 148                 return FAILED;
 149         }
 150
 151         set_bit(US_FLIDX_TIMED_OUT, &us->dflags);
 152         if (!test_bit(US_FLIDX_RESETTING, &us->dflags)) {
 153                 set_bit(US_FLIDX_ABORTING, &us->dflags);
 154                 usb_stor_stop_transport(us);
 155         }
 156         scsi_unlock(us_to_host(us));
 157
 158         /* Wait for the aborted command to finish */
 159         wait_for_completion(&us->notify);
 160         return SUCCESS;
 161 }
 162
 163 /* This invokes the transport reset mechanism to reset the state of the
 164  * device.
 165  */
 166 /*
 167  * device_reset()
 168  */
 169 static int device_reset(struct scsi_cmnd *srb)
 170 {
 171         struct us_data *us = host_to_us(srb->device->host);
 172         int result;
 173
 174         /* pr_info("scsiglue --- device_reset\n"); */
 175
 176         /* lock the device pointers and do the reset */
 177         mutex_lock(&(us->dev_mutex));
 178         result = us->transport_reset(us);
 179         mutex_unlock(&us->dev_mutex);
 180
 181         return result < 0 ? FAILED : SUCCESS;
 182 }
 183
 184 /*
 185  * bus_reset()
 186  */
 187 static int bus_reset(struct scsi_cmnd *srb)
 188 {
 189         struct us_data *us = host_to_us(srb->device->host);
 190         int result;
 191
 192         /* pr_info("scsiglue --- bus_reset\n"); */
 193         result = usb_stor_port_reset(us);
 194         return result < 0 ? FAILED : SUCCESS;
 195 }
 196
 197 /*
 198  * usb_stor_report_device_reset()
 199  */
 200 void usb_stor_report_device_reset(struct us_data *us)
 201 {
 202         int i;
 203         struct Scsi_Host *host = us_to_host(us);
 204
 205         /* pr_info("scsiglue --- usb_stor_report_device_reset\n"); */
 206         scsi_report_device_reset(host, 0, 0);
 207         if (us->fflags & US_FL_SCM_MULT_TARG) {
 208                 for (i = 1; i < host->max_id; ++i)
 209                         scsi_report_device_reset(host, 0, i);
 210         }
 211 }
 212
 213 /*
 214  * usb_stor_report_bus_reset()
 215  */
 216 void usb_stor_report_bus_reset(struct us_data *us)
 217 {
 218         struct Scsi_Host *host = us_to_host(us);
 219
 220         /* pr_info("scsiglue --- usb_stor_report_bus_reset\n"); */
 221         scsi_lock(host);
 222         scsi_report_bus_reset(host, 0);
 223         scsi_unlock(host);
 224 }
 225
 226 /***********************************************************************
 227  * /proc/scsi/ functions
 228  ***********************************************************************/
 229
 230 /* we use this macro to help us write into the buffer */
 231 #undef SPRINTF
 232 #define SPRINTF(args...) \
 233         do { if (pos < buffer+length) pos += sprintf(pos, ## args); } while (0)
 234
 235 /*
 236  * proc_info()
 237  */
 238 static int proc_info(struct Scsi_Host *host, char *buffer, char **start,
 239                                         off_t offset, int length, int inout)
 240 {
 241         struct us_data *us = host_to_us(host);
 242         char *pos = buffer;
 243         const char *string;
 244
 245         /* pr_info("scsiglue --- proc_info\n"); */
 246         if (inout)
 247                 return length;
 248
 249         /* print the controller name */
 250         SPRINTF("   Host scsi%d: usb-storage\n", host->host_no);
 251
 252         /* print product, vendor, and serial number strings */
 253         if (us->pusb_dev->manufacturer)
 254                 string = us->pusb_dev->manufacturer;
 255         else if (us->unusual_dev->vendorName)
 256                 string = us->unusual_dev->vendorName;
 257         else
 258                 string = "Unknown";
 259         SPRINTF("       Vendor: %s\n", string);
 260         if (us->pusb_dev->product)
 261                 string = us->pusb_dev->product;
 262         else if (us->unusual_dev->productName)
 263                 string = us->unusual_dev->productName;
 264         else
 265                 string = "Unknown";
 266         SPRINTF("      Product: %s\n", string);
 267         if (us->pusb_dev->serial)
 268                 string = us->pusb_dev->serial;
 269         else
 270                 string = "None";
 271         SPRINTF("Serial Number: %s\n", string);
 272
 273         /* show the protocol and transport */
 274         SPRINTF("     Protocol: %s\n", us->protocol_name);
 275         SPRINTF("    Transport: %s\n", us->transport_name);
 276
 277         /* show the device flags */
 278         if (pos < buffer + length) {
 279                 pos += sprintf(pos, "       Quirks:");
 280
 281 #define US_FLAG(name, value) \
 282         if (us->fflags & value) pos += sprintf(pos, " " #name);
 283 US_DO_ALL_FLAGS
 284 #undef US_FLAG
 285
 286                 *(pos++) = '\n';
 287         }
 288
 289         /* Calculate start of next buffer, and return value. */
 290         *start = buffer + offset;
 291
 292         if ((pos - buffer) < offset)
 293                 return 0;
 294         else if ((pos - buffer - offset) < length)
 295                 return pos - buffer - offset;
 296         else
 297                 return length;
 298 }
 299
 300 /***********************************************************************
 301  * Sysfs interface
 302  ***********************************************************************/
 303
 304 /* Output routine for the sysfs max_sectors file */
 305 /*
 306  * show_max_sectors()
 307  */
 308 static ssize_t show_max_sectors(struct device *dev,
 309                                 struct device_attribute *attr, char *buf)
 310 {
 311         struct scsi_device *sdev = to_scsi_device(dev);
 312
 313         /* pr_info("scsiglue --- ssize_t show_max_sectors\n"); */
 314         return sprintf(buf, "%u\n", queue_max_sectors(sdev->request_queue));
 315 }
 316
 317 /* Input routine for the sysfs max_sectors file */
 318 /*
 319  * store_max_sectors()
 320  */
 321 static ssize_t store_max_sectors(struct device *dev,
 322                                 struct device_attribute *attr,
 323                                 const char *buf, size_t count)
 324 {
 325         struct scsi_device *sdev = to_scsi_device(dev);
 326         unsigned short ms;
 327
 328         /* pr_info("scsiglue --- ssize_t store_max_sectors\n"); */
 329         if (sscanf(buf, "%hu", &ms) > 0 && ms <= SCSI_DEFAULT_MAX_SECTORS) {
 330                 blk_queue_max_hw_sectors(sdev->request_queue, ms);
 331                 return strlen(buf);
 332         }
 333         return -EINVAL;
 334 }
 335
 336 static DEVICE_ATTR(max_sectors, S_IRUGO | S_IWUSR, show_max_sectors, store_max_sectors);
 337 static struct device_attribute *sysfs_device_attr_list[] = {&dev_attr_max_sectors, NULL, };
 338
 339 /* this defines our host template, with which we'll allocate hosts */
 340
 341 /*
 342  * usb_stor_host_template()
 343  */
 344 struct scsi_host_template usb_stor_host_template = {
 345         /* basic userland interface stuff */
 346         .name =                         "eucr-storage",
 347         .proc_name =                    "eucr-storage",
 348         .proc_info =                    proc_info,
 349         .info =                         host_info,
 350
 351         /* command interface -- queued only */
 352         .queuecommand =                 queuecommand,
 353
 354         /* error and abort handlers */
 355         .eh_abort_handler =             command_abort,
 356         .eh_device_reset_handler =      device_reset,
 357         .eh_bus_reset_handler =         bus_reset,
 358
 359         /* queue commands only, only one command per LUN */
 360         .can_queue =                    1,
 361         .cmd_per_lun =                  1,
 362
 363         /* unknown initiator id */
 364         .this_id =                      -1,
 365
 366         .slave_alloc =                  slave_alloc,
 367         .slave_configure =              slave_configure,
 368
 369         /* lots of sg segments can be handled */
 370         .sg_tablesize =                 SG_ALL,
 371
 372         /* limit the total size of a transfer to 120 KB */
 373         .max_sectors =                  240,
 374
 375         /* merge commands... this seems to help performance, but
 376          * periodically someone should test to see which setting is more
 377          * optimal.
 378          */
 379         .use_clustering =               1,
 380
 381         /* emulated HBA */
 382         .emulated =                     1,
 383
 384         /* we do our own delay after a device or bus reset */
 385         .skip_settle_delay =            1,
 386
 387         /* sysfs device attributes */
 388         .sdev_attrs =                   sysfs_device_attr_list,
 389
 390         /* module management */
 391         .module =                       THIS_MODULE
 392 };
 393
 394 /* To Report "Illegal Request: Invalid Field in CDB */
 395 unsigned char usb_stor_sense_invalidCDB[18] = {
 396         [0]     = 0x70,                     /* current error */
 397         [2]     = ILLEGAL_REQUEST,          /* Illegal Request = 0x05 */
 398         [7]     = 0x0a,                     /* additional length */
 399         [12]    = 0x24                      /* Invalid Field in CDB */
 400 };
 401
 402 /***********************************************************************
 403  * Scatter-gather transfer buffer access routines
 404  ***********************************************************************/
 405
 406 /*
 407  * usb_stor_access_xfer_buf()
 408  */
 409 unsigned int usb_stor_access_xfer_buf(struct us_data *us, unsigned char *buffer,
 410         unsigned int buflen, struct scsi_cmnd *srb, struct scatterlist **sgptr,
 411         unsigned int *offset, enum xfer_buf_dir dir)
 412 {
 413         unsigned int cnt;
 414
 415         /* pr_info("transport --- usb_stor_access_xfer_buf\n"); */
 416         struct scatterlist *sg = *sgptr;
 417
 418         if (!sg)
 419                 sg = scsi_sglist(srb);
 420
 421         cnt = 0;
 422         while (cnt < buflen && sg) {
 423                 struct page *page = sg_page(sg) +
 424                                         ((sg->offset + *offset) >> PAGE_SHIFT);
 425                 unsigned int poff = (sg->offset + *offset) & (PAGE_SIZE-1);
 426                 unsigned int sglen = sg->length - *offset;
 427
 428                 if (sglen > buflen - cnt) {
 429                         /* Transfer ends within this s-g entry */
 430                         sglen = buflen - cnt;
 431                         *offset += sglen;
 432                 } else {
 433                         /* Transfer continues to next s-g entry */
 434                         *offset = 0;
 435                         sg = sg_next(sg);
 436                 }
 437
 438                 while (sglen > 0) {
 439                         unsigned int plen = min(sglen,
 440                                                 (unsigned int)PAGE_SIZE - poff);
 441                         unsigned char *ptr = kmap(page);
 442
 443                         if (dir == TO_XFER_BUF)
 444                                 memcpy(ptr + poff, buffer + cnt, plen);
 445                         else
 446                                 memcpy(buffer + cnt, ptr + poff, plen);
 447                         kunmap(page);
 448
 449                         /* Start at the beginning of the next page */
 450                         poff = 0;
 451                         ++page;
 452                         cnt += plen;
 453                         sglen -= plen;
 454                 }
 455         }
 456         *sgptr = sg;
 457
 458         /* Return the amount actually transferred */
 459         return cnt;
 460 }
 461
 462 /*
 463  * Store the contents of buffer into srb's transfer
 464  * buffer and set the SCSI residue.
 465  */
 466 /*
 467  * usb_stor_set_xfer_buf()
 468  */
 469 void usb_stor_set_xfer_buf(struct us_data *us, unsigned char *buffer,
 470                 unsigned int buflen, struct scsi_cmnd *srb, unsigned int dir)
 471 {
 472         unsigned int offset = 0;
 473         struct scatterlist *sg = NULL;
 474
 475         /* pr_info("transport --- usb_stor_set_xfer_buf\n"); */
 476         /* TO_XFER_BUF = 0, FROM_XFER_BUF = 1 */
 477         buflen = min(buflen, scsi_bufflen(srb));
 478         buflen = usb_stor_access_xfer_buf(us, buffer, buflen, srb,
 479                                                 &sg, &offset, dir);
 480         if (buflen < scsi_bufflen(srb))
 481                 scsi_set_resid(srb, scsi_bufflen(srb) - buflen);
 482 }