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-rw-r--r--block/scsi_ioctl.c101
1 files changed, 72 insertions, 29 deletions
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 24f7af9d0abc..b33eda26e205 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -350,16 +350,51 @@ out:
return ret;
}
+/**
+ * sg_scsi_ioctl -- handle deprecated SCSI_IOCTL_SEND_COMMAND ioctl
+ * @file: file this ioctl operates on (optional)
+ * @q: request queue to send scsi commands down
+ * @disk: gendisk to operate on (option)
+ * @sic: userspace structure describing the command to perform
+ *
+ * Send down the scsi command described by @sic to the device below
+ * the request queue @q. If @file is non-NULL it's used to perform
+ * fine-grained permission checks that allow users to send down
+ * non-destructive SCSI commands. If the caller has a struct gendisk
+ * available it should be passed in as @disk to allow the low level
+ * driver to use the information contained in it. A non-NULL @disk
+ * is only allowed if the caller knows that the low level driver doesn't
+ * need it (e.g. in the scsi subsystem).
+ *
+ * Notes:
+ * - This interface is deprecated - users should use the SG_IO
+ * interface instead, as this is a more flexible approach to
+ * performing SCSI commands on a device.
+ * - The SCSI command length is determined by examining the 1st byte
+ * of the given command. There is no way to override this.
+ * - Data transfers are limited to PAGE_SIZE
+ * - The length (x + y) must be at least OMAX_SB_LEN bytes long to
+ * accommodate the sense buffer when an error occurs.
+ * The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
+ * old code will not be surprised.
+ * - If a Unix error occurs (e.g. ENOMEM) then the user will receive
+ * a negative return and the Unix error code in 'errno'.
+ * If the SCSI command succeeds then 0 is returned.
+ * Positive numbers returned are the compacted SCSI error codes (4
+ * bytes in one int) where the lowest byte is the SCSI status.
+ */
#define OMAX_SB_LEN 16 /* For backward compatibility */
-
-static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
- struct gendisk *bd_disk, Scsi_Ioctl_Command __user *sic)
+int sg_scsi_ioctl(struct file *file, struct request_queue *q,
+ struct gendisk *disk, struct scsi_ioctl_command __user *sic)
{
struct request *rq;
int err;
unsigned int in_len, out_len, bytes, opcode, cmdlen;
char *buffer = NULL, sense[SCSI_SENSE_BUFFERSIZE];
+ if (!sic)
+ return -EINVAL;
+
/*
* get in an out lengths, verify they don't exceed a page worth of data
*/
@@ -393,45 +428,53 @@ static int sg_scsi_ioctl(struct file *file, request_queue_t *q,
if (copy_from_user(rq->cmd, sic->data, cmdlen))
goto error;
- if (copy_from_user(buffer, sic->data + cmdlen, in_len))
+ if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
goto error;
err = verify_command(file, rq->cmd);
if (err)
goto error;
+ /* default. possible overriden later */
+ rq->retries = 5;
+
switch (opcode) {
- case SEND_DIAGNOSTIC:
- case FORMAT_UNIT:
- rq->timeout = FORMAT_UNIT_TIMEOUT;
- break;
- case START_STOP:
- rq->timeout = START_STOP_TIMEOUT;
- break;
- case MOVE_MEDIUM:
- rq->timeout = MOVE_MEDIUM_TIMEOUT;
- break;
- case READ_ELEMENT_STATUS:
- rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
- break;
- case READ_DEFECT_DATA:
- rq->timeout = READ_DEFECT_DATA_TIMEOUT;
- break;
- default:
- rq->timeout = BLK_DEFAULT_TIMEOUT;
- break;
+ case SEND_DIAGNOSTIC:
+ case FORMAT_UNIT:
+ rq->timeout = FORMAT_UNIT_TIMEOUT;
+ rq->retries = 1;
+ break;
+ case START_STOP:
+ rq->timeout = START_STOP_TIMEOUT;
+ break;
+ case MOVE_MEDIUM:
+ rq->timeout = MOVE_MEDIUM_TIMEOUT;
+ break;
+ case READ_ELEMENT_STATUS:
+ rq->timeout = READ_ELEMENT_STATUS_TIMEOUT;
+ break;
+ case READ_DEFECT_DATA:
+ rq->timeout = READ_DEFECT_DATA_TIMEOUT;
+ rq->retries = 1;
+ break;
+ default:
+ rq->timeout = BLK_DEFAULT_TIMEOUT;
+ break;
+ }
+
+ if (bytes && blk_rq_map_kern(q, rq, buffer, bytes, __GFP_WAIT)) {
+ err = DRIVER_ERROR << 24;
+ goto out;
}
memset(sense, 0, sizeof(sense));
rq->sense = sense;
rq->sense_len = 0;
-
- rq->data = buffer;
- rq->data_len = bytes;
rq->flags |= REQ_BLOCK_PC;
- rq->retries = 0;
- blk_execute_rq(q, bd_disk, rq, 0);
+ blk_execute_rq(q, disk, rq, 0);
+
+out:
err = rq->errors & 0xff; /* only 8 bit SCSI status */
if (err) {
if (rq->sense_len && rq->sense) {
@@ -450,7 +493,7 @@ error:
blk_put_request(rq);
return err;
}
-
+EXPORT_SYMBOL_GPL(sg_scsi_ioctl);
/* Send basic block requests */
static int __blk_send_generic(request_queue_t *q, struct gendisk *bd_disk, int cmd, int data)