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 "../block/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->dev = 0xfffe; /* 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     scsi_do_cmd(SCpnt,  cmd, NULL,  0,
 117                 scsi_ioctl_done,  MAX_TIMEOUT,
 118                 MAX_RETRIES);
 119     
 120     if (SCpnt->request.dev != 0xfffe){
 121         struct semaphore sem = MUTEX_LOCKED;
 122         SCpnt->request.sem = &sem;
 123         down(&sem);
 124         /* Hmm.. Have to ask about this one */
 125         while (SCpnt->request.dev != 0xfffe) schedule();
 126     };
 127     
 128     if(driver_byte(SCpnt->result) != 0)
 129         switch(SCpnt->sense_buffer[2] & 0xf) {
 130         case ILLEGAL_REQUEST:
 131             if(cmd[0] == ALLOW_MEDIUM_REMOVAL) dev->lockable = 0;
 132             else printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
 133             break;
 134         case NOT_READY: /* This happens if there is no disc in drive */
 135             if(dev->removable){
 136                 printk("Device not ready.  Make sure there is a disc in the drive.\n");
 137                 break;
 138             };
 139         case UNIT_ATTENTION:
 140             if (dev->removable){
 141                 dev->changed = 1;
 142                 SCpnt->result = 0; /* This is no longer considered an error */
 143                 printk("Disc change detected.\n");
 144                 break;
 145             };
 146         default: /* Fall through for non-removable media */
 147             printk("SCSI error: host %d id %d lun %d return code = %x\n",
 148                    dev->host->host_no,
 149                    dev->id,
 150                    dev->lun,
 151                    SCpnt->result);
 152             printk("\tSense class %x, sense error %x, extended sense %x\n",
 153                    sense_class(SCpnt->sense_buffer[0]),
 154                    sense_error(SCpnt->sense_buffer[0]),
 155                    SCpnt->sense_buffer[2] & 0xf);
 156             
 157         };
 158     
 159     result = SCpnt->result;
 160     SCpnt->request.dev = -1;
 161     wake_up(&SCpnt->device->device_wait);
 162     return result;
 163 }
 164 
 165 /*
 166  * This interface is depreciated - users should use the scsi generics
 167  * interface instead, as this is a more flexible approach to performing
 168  * generic SCSI commands on a device.
 169  */
 170 static int ioctl_command(Scsi_Device *dev, void *buffer)
     /*  */
 171 {
 172     char * buf;
 173     char cmd[12];
 174     char * cmd_in;
 175     Scsi_Cmnd * SCpnt;
 176     unsigned char opcode;
 177     int inlen, outlen, cmdlen;
 178     int needed, buf_needed;
 179     int result;
 180     
 181     if (!buffer)
 182         return -EINVAL;
 183     
 184 
 185     /*
 186      * Verify that we can read at least this much.
 187      */
 188     result = verify_area(VERIFY_READ, buffer, 2*sizeof(long) + 1);
 189     if (result) return result;
 190 
 191     /*
 192      * The structure that we are passed should look like:
 193      *
 194      * struct sdata{
 195      *  int inlen;
 196      *  int outlen;
 197      *  char cmd[];  # However many bytes are used for cmd.
 198      *  char data[];
 199      */
 200     inlen = get_user((unsigned int *) buffer);
 201     outlen = get_user( ((unsigned int *) buffer) + 1);
 202     
 203     /*
 204      * We do not transfer more than MAX_BUF with this interface.
 205      * If the user needs to transfer more data than this, they
 206      * should use scsi_generics instead.
 207      */
 208     if( inlen > MAX_BUF ) inlen = MAX_BUF;
 209     if( outlen > MAX_BUF ) outlen = MAX_BUF;
 210 
 211     cmd_in = (char *) ( ((int *)buffer) + 2);
 212     opcode = get_user(cmd_in); 
 213     
 214     needed = buf_needed = (inlen > outlen ? inlen : outlen);
 215     if(buf_needed){
 216         buf_needed = (buf_needed + 511) & ~511;
 217         if (buf_needed > MAX_BUF) buf_needed = MAX_BUF;
 218         buf = (char *) scsi_malloc(buf_needed);
 219         if (!buf) return -ENOMEM;
 220         memset(buf, 0, buf_needed);
 221     } else
 222         buf = NULL;
 223     
 224     /*
 225      * Obtain the command from the user's address space.
 226      */
 227     cmdlen = COMMAND_SIZE(opcode);
 228 
 229     result = verify_area(VERIFY_READ, cmd_in, 
 230                          cmdlen + inlen > MAX_BUF ? MAX_BUF : inlen);
 231     if (result) return result;
 232 
 233     memcpy_fromfs ((void *) cmd,  cmd_in,  cmdlen);
 234     
 235     /*
 236      * Obtain the data to be sent to the device (if any).
 237      */
 238     memcpy_fromfs ((void *) buf,  
 239                    (void *) (cmd_in + cmdlen), 
 240                    inlen);
 241     
 242     /*
 243      * Set the lun field to the correct value.
 244      */
 245     cmd[1] = ( cmd[1] & 0x1f ) | (dev->lun << 5);
 246     
 247 #ifndef DEBUG_NO_CMD
 248     
 249     SCpnt = allocate_device(NULL, dev, 1);
 250     
 251     scsi_do_cmd(SCpnt,  cmd,  buf, needed,  scsi_ioctl_done,  MAX_TIMEOUT, 
 252                 MAX_RETRIES);
 253     
 254     if (SCpnt->request.dev != 0xfffe){
 255         struct semaphore sem = MUTEX_LOCKED;
 256         SCpnt->request.sem = &sem;
 257         down(&sem);
 258         /* Hmm.. Have to ask about this one */
 259         while (SCpnt->request.dev != 0xfffe) schedule();
 260     }
 261     
 262     
 263     /* 
 264      * If there was an error condition, pass the info back to the user. 
 265      */
 266     if(SCpnt->result) {
 267         result = verify_area(VERIFY_WRITE, 
 268                              cmd_in, 
 269                              sizeof(SCpnt->sense_buffer));
 270         if (result) return result;
 271         memcpy_tofs((void *) cmd_in,  
 272                     SCpnt->sense_buffer, 
 273                     sizeof(SCpnt->sense_buffer));
 274     } else {
 275         result = verify_area(VERIFY_WRITE, cmd_in, outlen);
 276         if (result) return result;
 277         memcpy_tofs ((void *) cmd_in,  buf,  outlen);
 278     }
 279     result = SCpnt->result;
 280     SCpnt->request.dev = -1;  /* Mark as not busy */
 281     if (buf) scsi_free(buf, buf_needed);
 282     
 283     if(SCpnt->device->scsi_request_fn)
 284         (*SCpnt->device->scsi_request_fn)();
 285     
 286     wake_up(&SCpnt->device->device_wait);
 287     return result;
 288 #else
 289     {
 290         int i;
 291         printk("scsi_ioctl : device %d.  command = ", dev->id);
 292         for (i = 0; i < 12; ++i)
 293             printk("%02x ", cmd[i]);
 294         printk("\nbuffer =");
 295         for (i = 0; i < 20; ++i)
 296             printk("%02x ", buf[i]);
 297         printk("\n");
 298         printk("inlen = %d, outlen = %d, cmdlen = %d\n",
 299                inlen, outlen, cmdlen);
 300         printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
 301     }
 302     return 0;
 303 #endif
 304 }
 305 
 306 /*
 307  * the scsi_ioctl() function differs from most ioctls in that it does
 308  * not take a major/minor number as the dev filed.  Rather, it takes
 309  * a pointer to a scsi_devices[] element, a structure. 
 310  */
 311 int scsi_ioctl (Scsi_Device *dev, int cmd, void *arg)
     /*  */
 312 {
 313     int result;
 314     char scsi_cmd[12];
 315     
 316     /* No idea how this happens.... */
 317     if (!dev) return -ENXIO;
 318     
 319     switch (cmd) {
 320     case SCSI_IOCTL_GET_IDLUN:
 321         result = verify_area(VERIFY_WRITE, (void *) arg, 2*sizeof(long));
 322         if (result) return result;
 323 
 324         put_user(dev->id 
 325                  + (dev->lun << 8) 
 326                  + (dev->channel << 16)
 327                  + ((dev->host->hostt->low_ino & 0xff) << 24),
 328                     (unsigned long *) arg);
 329         put_user( dev->host->unique_id, (unsigned long *) arg+1);
 330         return 0;
 331     case SCSI_IOCTL_TAGGED_ENABLE:
 332         if(!suser())  return -EACCES;
 333         if(!dev->tagged_supported) return -EINVAL;
 334         dev->tagged_queue = 1;
 335         dev->current_tag = 1;
 336         break;
 337     case SCSI_IOCTL_TAGGED_DISABLE:
 338         if(!suser())  return -EACCES;
 339         if(!dev->tagged_supported) return -EINVAL;
 340         dev->tagged_queue = 0;
 341         dev->current_tag = 0;
 342         break;
 343     case SCSI_IOCTL_PROBE_HOST:
 344         return ioctl_probe(dev->host, arg);
 345     case SCSI_IOCTL_SEND_COMMAND:
 346         if(!suser())  return -EACCES;
 347         return ioctl_command((Scsi_Device *) dev, arg);
 348     case SCSI_IOCTL_DOORLOCK:
 349         if (!dev->removable || !dev->lockable) return 0;
 350         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 351         scsi_cmd[1] = dev->lun << 5;
 352         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 353         scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
 354         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 355         break;
 356     case SCSI_IOCTL_DOORUNLOCK:
 357         if (!dev->removable || !dev->lockable) return 0;
 358         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 359         scsi_cmd[1] = dev->lun << 5;
 360         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 361         scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
 362         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 363     case SCSI_IOCTL_TEST_UNIT_READY:
 364         scsi_cmd[0] = TEST_UNIT_READY;
 365         scsi_cmd[1] = dev->lun << 5;
 366         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 367         scsi_cmd[4] = 0;
 368         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 369         break;
 370     default :           
 371         return -EINVAL;
 372     }
 373     return -EINVAL;
 374 }
 375 
 376 /*
 377  * Just like scsi_ioctl, only callable from kernel space with no 
 378  * fs segment fiddling.
 379  */
 380 
 381 int kernel_scsi_ioctl (Scsi_Device *dev, int cmd, void *arg) {
     /*  */
 382     unsigned long oldfs;
 383     int tmp;
 384     oldfs = get_fs();
 385     set_fs(get_ds());
 386     tmp = scsi_ioctl (dev, cmd, arg);
 387     set_fs(oldfs);
 388     return tmp;
 389 }
 390 
 391 /*
 392  * Overrides for Emacs so that we almost follow Linus's tabbing style.
 393  * Emacs will notice this stuff at the end of the file and automatically
 394  * adjust the settings for this buffer only.  This must remain at the end
 395  * of the file.
 396  * ---------------------------------------------------------------------------
 397  * Local variables:
 398  * c-indent-level: 4
 399  * c-brace-imaginary-offset: 0
 400  * c-brace-offset: -4
 401  * c-argdecl-indent: 4
 402  * c-label-offset: -4
 403  * c-continued-statement-offset: 4
 404  * c-continued-brace-offset: 0
 405  * indent-tabs-mode: nil
 406  * tab-width: 8
 407  * End:
 408  */
/* */
root/drivers/scsi/scsi_ioctl.c

DEFINITIONS
