scsi: reintroduce scsi_driver.init_command
Instead of letting the ULD play games with the prep_fn move back to
the model of a central prep_fn with a callback to the ULD. This
already cleans up and shortens the code by itself, and will be required
to properly support blk-mq in the SCSI midlayer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index efcbcd1..aa028d8 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -109,6 +109,8 @@
static int sd_suspend_runtime(struct device *);
static int sd_resume(struct device *);
static void sd_rescan(struct device *);
+static int sd_init_command(struct scsi_cmnd *SCpnt);
+static void sd_uninit_command(struct scsi_cmnd *SCpnt);
static int sd_done(struct scsi_cmnd *);
static int sd_eh_action(struct scsi_cmnd *, int);
static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
@@ -503,6 +505,8 @@
.pm = &sd_pm_ops,
},
.rescan = sd_rescan,
+ .init_command = sd_init_command,
+ .uninit_command = sd_uninit_command,
.done = sd_done,
.eh_action = sd_eh_action,
};
@@ -838,9 +842,9 @@
return scsi_setup_blk_pc_cmnd(sdp, rq);
}
-static void sd_unprep_fn(struct request_queue *q, struct request *rq)
+static void sd_uninit_command(struct scsi_cmnd *SCpnt)
{
- struct scsi_cmnd *SCpnt = rq->special;
+ struct request *rq = SCpnt->request;
if (rq->cmd_flags & REQ_DISCARD) {
free_page((unsigned long)rq->buffer);
@@ -853,18 +857,10 @@
}
}
-/**
- * sd_prep_fn - build a scsi (read or write) command from
- * information in the request structure.
- * @SCpnt: pointer to mid-level's per scsi command structure that
- * contains request and into which the scsi command is written
- *
- * Returns 1 if successful and 0 if error (or cannot be done now).
- **/
-static int sd_prep_fn(struct request_queue *q, struct request *rq)
+static int sd_init_command(struct scsi_cmnd *SCpnt)
{
- struct scsi_cmnd *SCpnt;
- struct scsi_device *sdp = q->queuedata;
+ struct request *rq = SCpnt->request;
+ struct scsi_device *sdp = SCpnt->device;
struct gendisk *disk = rq->rq_disk;
struct scsi_disk *sdkp;
sector_t block = blk_rq_pos(rq);
@@ -886,12 +882,6 @@
} else if (rq->cmd_flags & REQ_FLUSH) {
ret = scsi_setup_flush_cmnd(sdp, rq);
goto out;
- } else if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
- ret = scsi_setup_blk_pc_cmnd(sdp, rq);
- goto out;
- } else if (rq->cmd_type != REQ_TYPE_FS) {
- ret = BLKPREP_KILL;
- goto out;
}
ret = scsi_setup_fs_cmnd(sdp, rq);
if (ret != BLKPREP_OK)
@@ -903,11 +893,10 @@
* is used for a killable error condition */
ret = BLKPREP_KILL;
- SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
- "sd_prep_fn: block=%llu, "
- "count=%d\n",
- (unsigned long long)block,
- this_count));
+ SCSI_LOG_HLQUEUE(1,
+ scmd_printk(KERN_INFO, SCpnt,
+ "%s: block=%llu, count=%d\n",
+ __func__, (unsigned long long)block, this_count));
if (!sdp || !scsi_device_online(sdp) ||
block + blk_rq_sectors(rq) > get_capacity(disk)) {
@@ -1127,7 +1116,7 @@
*/
ret = BLKPREP_OK;
out:
- return scsi_prep_return(q, rq, ret);
+ return ret;
}
/**
@@ -2878,9 +2867,6 @@
sd_revalidate_disk(gd);
- blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
- blk_queue_unprep_rq(sdp->request_queue, sd_unprep_fn);
-
gd->driverfs_dev = &sdp->sdev_gendev;
gd->flags = GENHD_FL_EXT_DEVT;
if (sdp->removable) {
@@ -3028,8 +3014,6 @@
async_synchronize_full_domain(&scsi_sd_pm_domain);
async_synchronize_full_domain(&scsi_sd_probe_domain);
- blk_queue_prep_rq(sdkp->device->request_queue, scsi_prep_fn);
- blk_queue_unprep_rq(sdkp->device->request_queue, NULL);
device_del(&sdkp->dev);
del_gendisk(sdkp->disk);
sd_shutdown(dev);