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 #include <asm/io.h>
   2 #include <asm/segment.h>
   3 #include <asm/system.h>
   4 
   5 #include <linux/errno.h>
   6 #include <linux/kernel.h>
   7 #include <linux/sched.h>
   8 #include <linux/string.h>
   9 
  10 #include "../block/blk.h"
  11 #include "scsi.h"
  12 #include "hosts.h"
  13 #include "scsi_ioctl.h"
  14 
  15 #define MAX_RETRIES 5   
  16 #define MAX_TIMEOUT 200
  17 #define MAX_BUF 4096
  18 
  19 #define max(a,b) (((a) > (b)) ? (a) : (b))
  20 
  21 /*
  22  * If we are told to probe a host, we will return 0 if  the host is not
  23  * present, 1 if the host is present, and will return an identifying
  24  * string at *arg, if arg is non null, filling to the length stored at
  25  * (int *) arg
  26  */
  27 
  28 static int ioctl_probe(struct Scsi_Host * host, void *buffer)
     /*  */
  29 {
  30         int temp;
  31         unsigned int len,slen;
  32         const char * string;
  33         
  34         if ((temp = host->hostt->present) && buffer) {
  35                 len = get_fs_long ((unsigned long *) buffer);
  36                 string = host->hostt->info();
  37                 slen = strlen(string);
  38                 if (len > slen)
  39                         len = slen + 1;
  40                 verify_area(VERIFY_WRITE, buffer, len);
  41                 memcpy_tofs (buffer, string, len);
  42         }
  43         return temp;
  44 }
  45 
  46 /*
  47  * 
  48  * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
  49  * The MAX_TIMEOUT and MAX_RETRIES  variables are used.  
  50  * 
  51  * dev is the SCSI device struct ptr, *(int *) arg is the length of the
  52  * input data, if any, not including the command string & counts, 
  53  * *((int *)arg + 1) is the output buffer size in bytes.
  54  * 
  55  * *(char *) ((int *) arg)[2] the actual command byte.   
  56  * 
  57  * Note that no more than MAX_BUF data bytes will be transfered.  Since
  58  * SCSI block device size is 512 bytes, I figured 1K was good.
  59  * but (WDE) changed it to 8192 to handle large bad track buffers.
  60  * ERY: I changed this to a dynamic allocation using scsi_malloc - we were
  61  * getting a kernel stack overflow which was crashing the system when we
  62  * were using 8192 bytes.
  63  * 
  64  * This size *does not* include the initial lengths that were passed.
  65  * 
  66  * The SCSI command is read from the memory location immediately after the
  67  * length words, and the input data is right after the command.  The SCSI
  68  * routines know the command size based on the opcode decode.  
  69  * 
  70  * The output area is then filled in starting from the command byte. 
  71  */
  72 
  73 static void scsi_ioctl_done (Scsi_Cmnd * SCpnt)
     /*  */
  74 {
  75   struct request * req;
  76   
  77   req = &SCpnt->request;
  78   req->dev = 0xfffe; /* Busy, but indicate request done */
  79   
  80   if (req->sem != NULL) {
  81     up(req->sem);
  82   }
  83 }       
  84 
  85 static int ioctl_internal_command(Scsi_Device *dev, char * cmd)
     /*  */
  86 {
  87         int result;
  88         Scsi_Cmnd * SCpnt;
  89 
  90         SCpnt = allocate_device(NULL, dev, 1);
  91         scsi_do_cmd(SCpnt,  cmd, NULL,  0,
  92                         scsi_ioctl_done,  MAX_TIMEOUT,
  93                         MAX_RETRIES);
  94 
  95         if (SCpnt->request.dev != 0xfffe){
  96           struct semaphore sem = MUTEX_LOCKED;
  97           SCpnt->request.sem = &sem;
  98           down(&sem);
  99           /* Hmm.. Have to ask about this one */
 100           while (SCpnt->request.dev != 0xfffe) schedule();
 101         };
 102 
 103         if(driver_byte(SCpnt->result) != 0)
 104           switch(SCpnt->sense_buffer[2] & 0xf) {
 105           case ILLEGAL_REQUEST:
 106             if(cmd[0] == ALLOW_MEDIUM_REMOVAL) dev->lockable = 0;
 107             else printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
 108             break;
 109           case NOT_READY: /* This happens if there is no disc in drive */
 110             if(dev->removable){
 111               printk("Device not ready.  Make sure there is a disc in the drive.\n");
 112               break;
 113             };
 114           case UNIT_ATTENTION:
 115             if (dev->removable){
 116               dev->changed = 1;
 117               SCpnt->result = 0; /* This is no longer considered an error */
 118               printk("Disc change detected.\n");
 119               break;
 120             };
 121           default: /* Fall through for non-removable media */
 122             printk("SCSI CD error: host %d id %d lun %d return code = %x\n",
 123                    dev->host->host_no,
 124                    dev->id,
 125                    dev->lun,
 126                    SCpnt->result);
 127             printk("\tSense class %x, sense error %x, extended sense %x\n",
 128                    sense_class(SCpnt->sense_buffer[0]),
 129                    sense_error(SCpnt->sense_buffer[0]),
 130                    SCpnt->sense_buffer[2] & 0xf);
 131 
 132           };
 133 
 134         result = SCpnt->result;
 135         SCpnt->request.dev = -1;
 136         wake_up(&SCpnt->device->device_wait);
 137         return result;
 138 }
 139 
 140 static int ioctl_command(Scsi_Device *dev, void *buffer)
     /*  */
 141 {
 142         char * buf;
 143         char cmd[12];
 144         char * cmd_in;
 145         Scsi_Cmnd * SCpnt;
 146         unsigned char opcode;
 147         int inlen, outlen, cmdlen;
 148         int needed, buf_needed;
 149         int result;
 150 
 151         if (!buffer)
 152                 return -EINVAL;
 153         
 154         inlen = get_fs_long((unsigned long *) buffer);
 155         outlen = get_fs_long( ((unsigned long *) buffer) + 1);
 156 
 157         cmd_in = (char *) ( ((int *)buffer) + 2);
 158         opcode = get_fs_byte(cmd_in); 
 159 
 160         needed = buf_needed = (inlen > outlen ? inlen : outlen);
 161         if(buf_needed){
 162           buf_needed = (buf_needed + 511) & ~511;
 163           if (buf_needed > MAX_BUF) buf_needed = MAX_BUF;
 164           buf = (char *) scsi_malloc(buf_needed);
 165           if (!buf) return -ENOMEM;
 166         } else
 167           buf = NULL;
 168 
 169         memcpy_fromfs ((void *) cmd,  cmd_in,  cmdlen = COMMAND_SIZE (opcode));
 170         memcpy_fromfs ((void *) buf,  (void *) (cmd_in + cmdlen), inlen > MAX_BUF ? MAX_BUF : inlen);
 171 
 172         cmd[1] = ( cmd[1] & 0x1f ) | (dev->lun << 5);
 173 
 174 #ifndef DEBUG_NO_CMD
 175         
 176         SCpnt = allocate_device(NULL, dev, 1);
 177 
 178         scsi_do_cmd(SCpnt,  cmd,  buf, needed,  scsi_ioctl_done,  MAX_TIMEOUT, 
 179                         MAX_RETRIES);
 180 
 181         if (SCpnt->request.dev != 0xfffe){
 182           struct semaphore sem = MUTEX_LOCKED;
 183           SCpnt->request.sem = &sem;
 184           down(&sem);
 185           /* Hmm.. Have to ask about this one */
 186           while (SCpnt->request.dev != 0xfffe) schedule();
 187         };
 188 
 189 
 190         /* If there was an error condition, pass the info back to the user. */
 191         if(SCpnt->result) {
 192           result = verify_area(VERIFY_WRITE, cmd_in, sizeof(SCpnt->sense_buffer));
 193           if (result)
 194             return result;
 195           memcpy_tofs((void *) cmd_in,  SCpnt->sense_buffer, sizeof(SCpnt->sense_buffer));
 196         } else {
 197 
 198           result = verify_area(VERIFY_WRITE, cmd_in, (outlen > MAX_BUF) ? MAX_BUF  : outlen);
 199           if (result)
 200             return result;
 201           memcpy_tofs ((void *) cmd_in,  buf,  (outlen > MAX_BUF) ? MAX_BUF  : outlen);
 202         };
 203         result = SCpnt->result;
 204         SCpnt->request.dev = -1;  /* Mark as not busy */
 205         if (buf) scsi_free(buf, buf_needed);
 206 
 207         if(SCpnt->device->scsi_request_fn)
 208           (*SCpnt->device->scsi_request_fn)();
 209 
 210         wake_up(&SCpnt->device->device_wait);
 211         return result;
 212 #else
 213         {
 214         int i;
 215         printk("scsi_ioctl : device %d.  command = ", dev->id);
 216         for (i = 0; i < 12; ++i)
 217                 printk("%02x ", cmd[i]);
 218         printk("\nbuffer =");
 219         for (i = 0; i < 20; ++i)
 220                 printk("%02x ", buf[i]);
 221         printk("\n");
 222         printk("inlen = %d, outlen = %d, cmdlen = %d\n",
 223                 inlen, outlen, cmdlen);
 224         printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
 225         }
 226         return 0;
 227 #endif
 228 }
 229 
 230 /*
 231         the scsi_ioctl() function differs from most ioctls in that it does
 232         not take a major/minor number as the dev filed.  Rather, it takes
 233         a pointer to a scsi_devices[] element, a structure. 
 234 */
 235 int scsi_ioctl (Scsi_Device *dev, int cmd, void *arg)
     /*  */
 236 {
 237         char scsi_cmd[12];
 238 
 239         /* No idea how this happens.... */
 240         if (!dev) return -ENXIO;
 241         
 242         switch (cmd) {
 243                 case SCSI_IOCTL_GET_IDLUN:
 244                         verify_area(VERIFY_WRITE, (void *) arg, sizeof(int));
 245                         put_fs_long(dev->id + (dev->lun << 8) + 
 246                                     (dev->host->host_no << 16), (unsigned long *) arg);
 247                         return 0;
 248                 case SCSI_IOCTL_TAGGED_ENABLE:
 249                         if(!suser())  return -EACCES;
 250                         if(!dev->tagged_supported) return -EINVAL;
 251                         dev->tagged_queue = 1;
 252                         dev->current_tag = 1;
 253                         break;
 254                 case SCSI_IOCTL_TAGGED_DISABLE:
 255                         if(!suser())  return -EACCES;
 256                         if(!dev->tagged_supported) return -EINVAL;
 257                         dev->tagged_queue = 0;
 258                         dev->current_tag = 0;
 259                         break;
 260                 case SCSI_IOCTL_PROBE_HOST:
 261                         return ioctl_probe(dev->host, arg);
 262                 case SCSI_IOCTL_SEND_COMMAND:
 263                         if(!suser())  return -EACCES;
 264                         return ioctl_command((Scsi_Device *) dev, arg);
 265                 case SCSI_IOCTL_DOORLOCK:
 266                         if (!dev->removable || !dev->lockable) return 0;
 267                         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 268                         scsi_cmd[1] = dev->lun << 5;
 269                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 270                         scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
 271                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 272                         break;
 273                 case SCSI_IOCTL_DOORUNLOCK:
 274                         if (!dev->removable || !dev->lockable) return 0;
 275                         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 276                         scsi_cmd[1] = dev->lun << 5;
 277                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 278                         scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
 279                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 280                 case SCSI_IOCTL_TEST_UNIT_READY:
 281                         scsi_cmd[0] = TEST_UNIT_READY;
 282                         scsi_cmd[1] = dev->lun << 5;
 283                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 284                         scsi_cmd[4] = 0;
 285                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 286                         break;
 287                 default :                       
 288                         return -EINVAL;
 289         }
 290         return -EINVAL;
 291 }
 292 
 293 /*
 294  * Just like scsi_ioctl, only callable from kernel space with no 
 295  * fs segment fiddling.
 296  */
 297 
 298 int kernel_scsi_ioctl (Scsi_Device *dev, int cmd, void *arg) {
     /*  */
 299   unsigned long oldfs;
 300   int tmp;
 301   oldfs = get_fs();
 302   set_fs(get_ds());
 303   tmp = scsi_ioctl (dev, cmd, arg);
 304   set_fs(oldfs);
 305   return tmp;
 306 }
/* */
root/drivers/scsi/scsi_ioctl.c

DEFINITIONS
