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   struct task_struct * p;
  77   
  78   req = &SCpnt->request;
  79   req->dev = 0xfffe; /* Busy, but indicate request done */
  80   
  81   if ((p = req->waiting) != NULL) {
  82     req->waiting = NULL;
  83     p->state = TASK_RUNNING;
  84     if (p->counter > current->counter)
  85       need_resched = 1;
  86   }
  87 }       
  88 
  89 static int ioctl_internal_command(Scsi_Device *dev, char * cmd)
     /*  */
  90 {
  91         int result;
  92         Scsi_Cmnd * SCpnt;
  93 
  94         SCpnt = allocate_device(NULL, dev->index, 1);
  95         scsi_do_cmd(SCpnt,  cmd, NULL,  0,
  96                         scsi_ioctl_done,  MAX_TIMEOUT,
  97                         MAX_RETRIES);
  98 
  99         if (SCpnt->request.dev != 0xfffe){
 100           SCpnt->request.waiting = current;
 101           current->state = TASK_UNINTERRUPTIBLE;
 102           while (SCpnt->request.dev != 0xfffe) schedule();
 103         };
 104 
 105         if(driver_byte(SCpnt->result) != 0)
 106           switch(SCpnt->sense_buffer[2] & 0xf) {
 107           case ILLEGAL_REQUEST:
 108             if(cmd[0] == ALLOW_MEDIUM_REMOVAL) dev->lockable = 0;
 109             else printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
 110             break;
 111           case NOT_READY: /* This happens if there is no disc in drive */
 112             if(dev->removable){
 113               printk("Device not ready.  Make sure there is a disc in the drive.\n");
 114               break;
 115             };
 116           case UNIT_ATTENTION:
 117             if (dev->removable){
 118               dev->changed = 1;
 119               SCpnt->result = 0; /* This is no longer considered an error */
 120               printk("Disc change detected.\n");
 121               break;
 122             };
 123           default: /* Fall through for non-removable media */
 124             printk("SCSI CD error: host %d id %d lun %d return code = %x\n",
 125                    dev->host->host_no,
 126                    dev->id,
 127                    dev->lun,
 128                    SCpnt->result);
 129             printk("\tSense class %x, sense error %x, extended sense %x\n",
 130                    sense_class(SCpnt->sense_buffer[0]),
 131                    sense_error(SCpnt->sense_buffer[0]),
 132                    SCpnt->sense_buffer[2] & 0xf);
 133 
 134           };
 135 
 136         result = SCpnt->result;
 137         SCpnt->request.dev = -1;  /* Mark as not busy */
 138         wake_up(&scsi_devices[SCpnt->index].device_wait);
 139         return result;
 140 }
 141 
 142 static int ioctl_command(Scsi_Device *dev, void *buffer)
     /*  */
 143 {
 144         char * buf;
 145         char cmd[12];
 146         char * cmd_in;
 147         Scsi_Cmnd * SCpnt;
 148         unsigned char opcode;
 149         int inlen, outlen, cmdlen;
 150         int needed;
 151         int result;
 152 
 153         if (!buffer)
 154                 return -EINVAL;
 155         
 156         inlen = get_fs_long((unsigned long *) buffer);
 157         outlen = get_fs_long( ((unsigned long *) buffer) + 1);
 158 
 159         cmd_in = (char *) ( ((int *)buffer) + 2);
 160         opcode = get_fs_byte(cmd_in); 
 161 
 162         needed = (inlen > outlen ? inlen : outlen);
 163         if(needed){
 164           needed = (needed + 511) & ~511;
 165           if (needed > MAX_BUF) needed = MAX_BUF;
 166           buf = (char *) scsi_malloc(needed);
 167           if (!buf) return -ENOMEM;
 168         } else
 169           buf = NULL;
 170 
 171         memcpy_fromfs ((void *) cmd,  cmd_in,  cmdlen = COMMAND_SIZE (opcode));
 172         memcpy_fromfs ((void *) buf,  (void *) (cmd_in + cmdlen), inlen > MAX_BUF ? MAX_BUF : inlen);
 173 
 174         cmd[1] = ( cmd[1] & 0x1f ) | (dev->lun << 5);
 175 
 176 #ifndef DEBUG_NO_CMD
 177         
 178         SCpnt = allocate_device(NULL, dev->index, 1);
 179 
 180         scsi_do_cmd(SCpnt,  cmd,  buf, needed,  scsi_ioctl_done,  MAX_TIMEOUT, 
 181                         MAX_RETRIES);
 182 
 183         if (SCpnt->request.dev != 0xfffe){
 184           SCpnt->request.waiting = current;
 185           current->state = TASK_UNINTERRUPTIBLE;
 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, needed);
 206         wake_up(&scsi_devices[SCpnt->index].device_wait);
 207         return result;
 208 #else
 209         {
 210         int i;
 211         printk("scsi_ioctl : device %d.  command = ", dev->id);
 212         for (i = 0; i < 12; ++i)
 213                 printk("%02x ", cmd[i]);
 214         printk("\nbuffer =");
 215         for (i = 0; i < 20; ++i)
 216                 printk("%02x ", buf[i]);
 217         printk("\n");
 218         printk("inlen = %d, outlen = %d, cmdlen = %d\n",
 219                 inlen, outlen, cmdlen);
 220         printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
 221         }
 222         return 0;
 223 #endif
 224 }
 225 
 226         
 227 
 228 /*
 229         the scsi_ioctl() function differs from most ioctls in that it does
 230         not take a major/minor number as the dev filed.  Rather, it takes
 231         a pointer to a scsi_devices[] element, a structure. 
 232 */
 233 int scsi_ioctl (Scsi_Device *dev, int cmd, void *arg)
     /*  */
 234 {
 235         char scsi_cmd[12];
 236 
 237         if ((cmd != 0 && dev->index > NR_SCSI_DEVICES))
 238                 return -ENODEV;
 239         
 240         switch (cmd) {
 241                 case SCSI_IOCTL_GET_IDLUN:
 242                         verify_area(VERIFY_WRITE, (void *) arg, sizeof(int));
 243                         put_fs_long(dev->id + (dev->lun << 8) + 
 244                                     (dev->host->host_no << 16), (unsigned long *) arg);
 245                         return 0;
 246                 case SCSI_IOCTL_TAGGED_ENABLE:
 247                         if(!suser())  return -EACCES;
 248                         if(!dev->tagged_supported) return -EINVAL;
 249                         dev->tagged_queue = 1;
 250                         dev->current_tag = 1;
 251                         break;
 252                 case SCSI_IOCTL_TAGGED_DISABLE:
 253                         if(!suser())  return -EACCES;
 254                         if(!dev->tagged_supported) return -EINVAL;
 255                         dev->tagged_queue = 0;
 256                         dev->current_tag = 0;
 257                         break;
 258                 case SCSI_IOCTL_PROBE_HOST:
 259                         return ioctl_probe(dev->host, arg);
 260                 case SCSI_IOCTL_SEND_COMMAND:
 261                         if(!suser())  return -EACCES;
 262                         return ioctl_command((Scsi_Device *) dev, arg);
 263                 case SCSI_IOCTL_DOORLOCK:
 264                         if (!dev->removable || !dev->lockable) return 0;
 265                         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 266                         scsi_cmd[1] = dev->lun << 5;
 267                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 268                         scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
 269                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 270                         break;
 271                 case SCSI_IOCTL_DOORUNLOCK:
 272                         if (!dev->removable || !dev->lockable) return 0;
 273                         scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
 274                         scsi_cmd[1] = dev->lun << 5;
 275                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 276                         scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
 277                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 278                 case SCSI_IOCTL_TEST_UNIT_READY:
 279                         scsi_cmd[0] = TEST_UNIT_READY;
 280                         scsi_cmd[1] = dev->lun << 5;
 281                         scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
 282                         scsi_cmd[4] = 0;
 283                         return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd);
 284                         break;
 285                 default :                       
 286                         return -EINVAL;
 287         }
 288         return -EINVAL;
 289 }
 290 
 291 /*
 292  * Just like scsi_ioctl, only callable from kernel space with no 
 293  * fs segment fiddling.
 294  */
 295 
 296 int kernel_scsi_ioctl (Scsi_Device *dev, int cmd, void *arg) {
     /*  */
 297   unsigned long oldfs;
 298   int tmp;
 299   oldfs = get_fs();
 300   set_fs(get_ds());
 301   tmp = scsi_ioctl (dev, cmd, arg);
 302   set_fs(oldfs);
 303   return tmp;
 304 }
 305
/* */
root/drivers/scsi/scsi_ioctl.c

DEFINITIONS
