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

DEFINITIONS
