drivers/staging/keucr/scsiglue.c

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