drivers/scsi/scsi

/* */
This source file includes following definitions.
ioctl_probe
scsi_ioctl_done
ioctl_internal_command
ioctl_command
scsi_ioctl
kernel_scsi_ioctl
   1 #ifdef MODULE
   2 /*
   3  * Don't import our own symbols, as this would severely mess up our
   4  * symbol tables.
   5  */
   6 #define _SCSI_SYMS_VER_
   7 #include <linux/autoconf.h>
   8 #include <linux/module.h>
   9 #include <linux/version.h>
  10 #else
  11 #define MOD_INC_USE_COUNT
  12 #define MOD_DEC_USE_COUNT
  13 #endif
  14 
  15 #include <asm/io.h>
  16 #include <asm/segment.h>
  17 #include <asm/system.h>
  18 
  19 #include <linux/errno.h>
  20 #include <linux/kernel.h>
  21 #include <linux/sched.h>
  22 #include <linux/mm.h>
  23 #include <linux/string.h>
  24 
  25 #include <linux/blk.h>
  26 #include "scsi.h"
  27 #include "hosts.h"
  28 #include "scsi_ioctl.h"
  29 
  30 #define MAX_RETRIES 5   
  31 #define MAX_TIMEOUT 900
  32 #define MAX_BUF 4096
  33 
  34 #define max(a,b) (((a) > (b)) ? (a) : (b))
  35 
  36 /*
  37  * If we are told to probe a host, we will return 0 if  the host is not
  38  * present, 1 if the host is present, and will return an identifying
  39  * string at *arg, if arg is non null, filling to the length stored at
  40  * (int *) arg
  41  */
  42 
  43 static int ioctl_probe(struct Scsi_Host * host, void *buffer)
     /*  */
  44 {
  45     int temp, result;
  46     unsigned int len,slen;
  47     const char * string;
  48     
  49     if ((temp = host->hostt->present) && buffer) {
  50         result = verify_area(VERIFY_READ, buffer, sizeof(long));
  51         if (result) return result;
  52 
  53         len = get_user ((unsigned int *) buffer);
  54         if(host->hostt->info)
  55             string = host->hostt->info(host);
  56         else 
  57             string = host->hostt->name;
  58         if(string) {
  59             slen = strlen(string);
  60             if (len > slen)
  61                 len = slen + 1;
  62             result = verify_area(VERIFY_WRITE, buffer, len);
  63             if (result) return result;
  64 
  65             memcpy_tofs (buffer, string, len);
  66         }
  67     }
  68     return temp;
  69 }
  70 
  71 /*
  72  * 
  73  * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
  74  * The MAX_TIMEOUT and MAX_RETRIES  variables are used.  
  75  * 
  76  * dev is the SCSI device struct ptr, *(int *) arg is the length of the
  77  * input data, if any, not including the command string & counts, 
  78  * *((int *)arg + 1) is the output buffer size in bytes.
  79  * 
  80  * *(char *) ((int *) arg)[2] the actual command byte.   
  81  * 
  82  * Note that no more than MAX_BUF data bytes will be transfered.  Since
  83  * SCSI block device size is 512 bytes, I figured 1K was good.
  84  * but (WDE) changed it to 8192 to handle large bad track buffers.
  85  * ERY: I changed this to a dynamic allocation using scsi_malloc - we were
  86  * getting a kernel stack overflow which was crashing the system when we
  87  * were using 8192 bytes.
  88  * 
  89  * This size *does not* include the initial lengths that were passed.
  90  * 
  91  * The SCSI command is read from the memory location immediately after the
  92  * length words, and the input data is right after the command.  The SCSI
  93  * routines know the command size based on the opcode decode.  
  94  * 
  95  * The output area is then filled in starting from the command byte. 
  96  */
  97 
  98 static void scsi_ioctl_done (Scsi_Cmnd * SCpnt)
     /*  */
  99 {
 100     struct request * req;
 101     
 102     req = &SCpnt->request;
 103     req->rq_status = RQ_SCSI_DONE; /* Busy, but indicate request done */
 104     
 105     if (req->sem != NULL) {
 106         up(req->sem);
 107     }
 108 }   
 109 
 110 static int ioctl_internal_command(Scsi_Device *dev, char * cmd)
     /*  */
 111 {
 112     int result;
 113     Scsi_Cmnd * SCpnt;
 114     
 115     SCpnt = allocate_device(NULL, dev, 1);
 116     {
 117         struct semaphore sem = MUTEX_LOCKED;
 118         SCpnt->request.sem = &sem;
 119         scsi_do_cmd(SCpnt,  cmd, NULL,  0,
 120                     scsi_ioctl_done,  MAX_TIMEOUT,
 121                     MAX_RETRIES);
 122         down(&sem);
 123     }
 124     
 125     if(driver_byte(SCpnt->result) != 0)
 126         switch(SCpnt->sense_buffer[2] & 0xf) {
 127         case ILLEGAL_REQUEST:
 128             if(cmd[0] == ALLOW_MEDIUM_REMOVAL) dev->lockable = 0;
 129             else printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
 130             break;
 131         case NOT_READY: /* This happens if there is no disc in drive */
 132             if(dev->removable){
 133                 printk("Device not ready.  Make sure there is a disc in the drive.\n");
 134                 break;
 135             };
 136         case UNIT_ATTENTION:
 137             if (dev->removable){
 138                 dev->changed = 1;
 139                 SCpnt->result = 0; /* This is no longer considered an error */
 140                 printk("Disc change detected.\n");
 141                 break;
 142             };
 143         default: /* Fall through for non-removable media */
 144             printk("SCSI error: host %d id %d lun %d return code = %x\n",
 145                    dev->host->host_no,
 146                    dev->id,
 147                    dev->lun,
 148                    SCpnt->result);
 149             printk("\tSense class %x, sense error %x, extended sense %x\n",
 150                    sense_class(SCpnt->sense_buffer[0]),
 151                    sense_error(SCpnt->sense_buffer[0]),
 152                    SCpnt->sense_buffer[2] & 0xf);
 153             
 154         };
 155     
 156     result = SCpnt->result;
 157     SCpnt->request.rq_status = RQ_INACTIVE;
 158     wake_up(&SCpnt->device->device_wait);
 159     return result;
 160 }
 161 
 162 /*
 163  * This interface is depreciated - users should use the scsi generics
 164  * interface instead, as this is a more flexible approach to performing
 165  * generic SCSI commands on a device.
 166  */
 167 static int ioctl_command(Scsi_Device *dev, void *buffer)
     /*  */
 168 {
 169     char * buf;
 170     char cmd[12];
 171     char * cmd_in;
 172     Scsi_Cmnd * SCpnt;
 173     unsigned char opcode;
 174     int inlen, outlen, cmdlen;
 175     int needed, buf_needed;
 176     int result;
 177     
 178     if (!buffer)
 179         return -EINVAL;
 180     
 181 
 182     /*
 183      * Verify that we can read at least this much.
 184      */
 185     result = verify_area(VERIFY_READ, buffer, 2*sizeof(long) + 1);
 186     if (result) return result;
 187 
 188     /*
 189      * The structure that we are passed should look like:
 190      *
 191      * struct sdata{
 192      *  int inlen;
 193      *  int outlen;
 194      *  char cmd[];  # However many bytes are used for cmd.
 195      *  char data[];
 196      */
 197     inlen = get_user((unsigned int *) buffer);
 198     outlen = get_user( ((unsigned int *) buffer) + 1);
 199     
 200     /*
 201      * We do not transfer more than MAX_BUF with this interface.
 202      * If the user needs to transfer more data than this, they
 203      * should use scsi_generics instead.
 204      */
 205     if( inlen > MAX_BUF ) inlen = MAX_BUF;
 206     if( outlen > MAX_BUF ) outlen = MAX_BUF;
 207 
 208     cmd_in = (char *) ( ((int *)buffer) + 2);
 209     opcode = get_user(cmd_in); 
 210     
 211     needed = buf_needed = (inlen > outlen ? inlen : outlen);
 212     if(buf_needed){
 213         buf_needed = (buf_needed + 511) & ~511;
 214         if (buf_needed > MAX_BUF) buf_needed = MAX_BUF;
 215         buf = (char *) scsi_malloc(buf_needed);
 216         if (!buf) return -ENOMEM;
 217         memset(buf, 0, buf_needed);
 218     } else
 219         buf = NULL;
 220     
 221     /*
 222      * Obtain the command from the user's address space.
 223      */
 224     cmdlen = COMMAND_SIZE(opcode);
 225 
 226     result = verify_area(VERIFY_READ, cmd_in, 
 227                          cmdlen + inlen > MAX_BUF ? MAX_BUF : inlen);
 228     if (result) return result;
 229 
 230     memcpy_fromfs ((void *) cmd,  cmd_in,  cmdlen);
 231     
 232     /*
 233      * Obtain the data to be sent to the device (if any).
 234      */
 235     memcpy_fromfs ((void *) buf,  
 236                    (void *) (cmd_in + cmdlen), 
 237                    inlen);
 238     
 239     /*
 240      * Set the lun field to the correct value.
 241      */
 242     cmd[1] = ( cmd[1] & 0x1f ) | (dev->lun << 5);
 243     
 244 #ifndef DEBUG_NO_CMD
 245     
 246     SCpnt = allocate_device(NULL, dev, 1);
 247 
 248     {
 249         struct semaphore sem = MUTEX_LOCKED;
 250         SCpnt->request.sem = &sem;
 251         scsi_do_cmd(SCpnt,  cmd,  buf, needed,  scsi_ioctl_done,  MAX_TIMEOUT, 
 252                     MAX_RETRIES);
 253         down(&sem);
 254     }
 255     
 256     /* 
 257      * If there was an error condition, pass the info back to the user. 
 258      */
 259     if(SCpnt->result) {
 260         result = verify_area(VERIFY_WRITE, 
 261                              cmd_in, 
 262                              sizeof(SCpnt->sense_buffer));
 263         if (result) return result;
 264         memcpy_tofs((void *) cmd_in,  
 265                     SCpnt->sense_buffer, 
 266                     sizeof(SCpnt->sense_buffer));
 267     } else {
 268         result = verify_area(VERIFY_WRITE, cmd_in, outlen);
 269         if (result) return result;
 270         memcpy_tofs ((void *) cmd_in,  buf,  outlen);
 271     }
 272     result = SCpnt->result;
 273 
 274     SCpnt->request.rq_status = RQ_INACTIVE;
 275 
 276     if (buf) scsi_free(buf, buf_needed);
 277     
 278     if(SCpnt->device->scsi_request_fn)
 279         (*SCpnt->device->scsi_request_fn)();
 280     
 281     wake_up(&SCpnt->device->device_wait);
 282     return result;
 283 #else
 284     {
 285         int i;
 286         printk("scsi_ioctl : device %d.  command = ", dev->id);
 287         for (i = 0; i < 12; ++i)
 288             printk("%02x ", cmd[i]);
 289         printk("\nbuffer =");
 290         for (i = 0; i < 20; ++i)
 291             printk("%02x ", buf[i]);
 292         printk("\n");
 293         printk("inlen = %d, outlen = %d, cmdlen = %d\n",
 294                inlen, outlen, cmdlen);
 295         printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
 296     }
 297     return 0;
 298 #endif
 299 }
 300 
 301 /*
 302  * the scsi_ioctl() function differs from most ioctls in that it does
 303  * not take a major/minor number as the dev filed.  Rather, it takes
 304  * a pointer to a scsi_devices[] element, a structure. 
 305  */
 306 int scsi_ioctl (Scsi_Device *dev, int cmd, void *arg)
     /*  */
 307 {
 308     int result;
 309     char scsi_cmd[12];
 310     
 311     /* No idea how this happens.... */
 312     if (!dev) return -ENXIO;
 313     
 314     switch (cmd) {
 315     case SCSI_IOCTL_GET_IDLUN:
 316         result = verify_area(VERIFY_WRITE, (void *) arg, 2*sizeof(long));
 317         if (result) return result;
 318 
 319         put_user(dev->id 
 320                  + (dev->lun << 8) 
 321                  + (dev->channel << 16)
 322                  + ((dev->host->hostt->proc_dir->low_ino & 0xff) << 24),
 323                     (unsigned long *) arg);
 324         put_user( dev->host->unique_id, (unsigned long *) arg+1);
 325         return 0;
 326     case SCSI_IOCTL_TAGGED_ENABLE:
 327         if(!suser())  return -EACCES;
 328         if(!dev->tagged_supported) return -EINVAL;
 329         dev->tagged_queue = 1;
 330         dev->current_tag = 1;
 331         break;
 332     case SCSI_IOCTL_TAGGED_DISABLE:
 333         if(!suser())  return -EACCES;
 334         if(!dev->tagged_supported) return -EINVAL;
 335         dev->tagged_queue = 0;
 336         dev->current_tag = 0;
 337         break;
 338     case SCSI_IOCTL_PROBE_HOST:
 339         return ioctl_probe(dev->host, arg);
 340     case SCSI_IOCTL_SEND_COMMAND:
 341         if(!suser())  return -EACCES;
 342         return ioctl_command((Scsi_Device *) dev, arg);
 343     case SCSI_IOCTL_DOORLOCK:
 344         if (!dev->removable || !dev->lockable) return 0;
 345         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 346         scsi_cmd[1] = dev->lun << 5;
 347         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 348         scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
 349         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 350         break;
 351     case SCSI_IOCTL_DOORUNLOCK:
 352         if (!dev->removable || !dev->lockable) return 0;
 353         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 354         scsi_cmd[1] = dev->lun << 5;
 355         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 356         scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
 357         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 358     case SCSI_IOCTL_TEST_UNIT_READY:
 359         scsi_cmd[0] = TEST_UNIT_READY;
 360         scsi_cmd[1] = dev->lun << 5;
 361         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 362         scsi_cmd[4] = 0;
 363         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 364         break;
 365     default :           
 366         return -EINVAL;
 367     }
 368     return -EINVAL;
 369 }
 370 
 371 /*
 372  * Just like scsi_ioctl, only callable from kernel space with no 
 373  * fs segment fiddling.
 374  */
 375 
 376 int kernel_scsi_ioctl (Scsi_Device *dev, int cmd, void *arg) {
     /*  */
 377     unsigned long oldfs;
 378     int tmp;
 379     oldfs = get_fs();
 380     set_fs(get_ds());
 381     tmp = scsi_ioctl (dev, cmd, arg);
 382     set_fs(oldfs);
 383     return tmp;
 384 }
 385 
 386 /*
 387  * Overrides for Emacs so that we almost follow Linus's tabbing style.
 388  * Emacs will notice this stuff at the end of the file and automatically
 389  * adjust the settings for this buffer only.  This must remain at the end
 390  * of the file.
 391  * ---------------------------------------------------------------------------
 392  * Local variables:
 393  * c-indent-level: 4
 394  * c-brace-imaginary-offset: 0
 395  * c-brace-offset: -4
 396  * c-argdecl-indent: 4
 397  * c-label-offset: -4
 398  * c-continued-statement-offset: 4
 399  * c-continued-brace-offset: 0
 400  * indent-tabs-mode: nil
 401  * tab-width: 8
 402  * End:
 403  */
/* */
root/drivers/scsi/scsi_ioctl.c

DEFINITIONS
