Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block into for-3.18

This is to receive 0a30288da1ae ("blk-mq, percpu_ref: implement a
kludge for SCSI blk-mq stall during probe") which implements
__percpu_ref_kill_expedited() to work around SCSI blk-mq stall.  The
commit reverted and patches to implement proper fix will be added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>

1 files changed, 27 insertions, 13 deletions

diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 51bf5155ee75..9b8eaeca6a79 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -279,7 +279,6 @@ static int blk_complete_sghdr_rq(struct request *rq, struct sg_io_hdr *hdr,
 	r = blk_rq_unmap_user(bio);
 	if (!ret)
 		ret = r;
-	blk_put_request(rq);
 
 	return ret;
 }
@@ -297,8 +296,6 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 
 	if (hdr->interface_id != 'S')
 		return -EINVAL;
-	if (hdr->cmd_len > BLK_MAX_CDB)
-		return -EINVAL;
 
 	if (hdr->dxfer_len > (queue_max_hw_sectors(q) << 9))
 		return -EIO;
@@ -317,16 +314,23 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 	if (hdr->flags & SG_FLAG_Q_AT_HEAD)
 		at_head = 1;
 
+	ret = -ENOMEM;
 	rq = blk_get_request(q, writing ? WRITE : READ, GFP_KERNEL);
 	if (!rq)
-		return -ENOMEM;
+		goto out;
 	blk_rq_set_block_pc(rq);
 
-	if (blk_fill_sghdr_rq(q, rq, hdr, mode)) {
-		blk_put_request(rq);
-		return -EFAULT;
+	if (hdr->cmd_len > BLK_MAX_CDB) {
+		rq->cmd = kzalloc(hdr->cmd_len, GFP_KERNEL);
+		if (!rq->cmd)
+			goto out_put_request;
 	}
 
+	ret = -EFAULT;
+	if (blk_fill_sghdr_rq(q, rq, hdr, mode))
+		goto out_free_cdb;
+
+	ret = 0;
 	if (hdr->iovec_count) {
 		size_t iov_data_len;
 		struct iovec *iov = NULL;
@@ -335,7 +339,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 					    0, NULL, &iov);
 		if (ret < 0) {
 			kfree(iov);
-			goto out;
+			goto out_free_cdb;
 		}
 
 		iov_data_len = ret;
@@ -358,7 +362,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 				      GFP_KERNEL);
 
 	if (ret)
-		goto out;
+		goto out_free_cdb;
 
 	bio = rq->bio;
 	memset(sense, 0, sizeof(sense));
@@ -376,9 +380,14 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
 
 	hdr->duration = jiffies_to_msecs(jiffies - start_time);
 
-	return blk_complete_sghdr_rq(rq, hdr, bio);
-out:
+	ret = blk_complete_sghdr_rq(rq, hdr, bio);
+
+out_free_cdb:
+	if (rq->cmd != rq->__cmd)
+		kfree(rq->cmd);
+out_put_request:
 	blk_put_request(rq);
+out:
 	return ret;
 }
 
@@ -448,6 +457,11 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 	}
 
 	rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
+	if (!rq) {
+		err = -ENOMEM;
+		goto error;
+	}
+	blk_rq_set_block_pc(rq);
 
 	cmdlen = COMMAND_SIZE(opcode);
 
@@ -501,7 +515,6 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
 	memset(sense, 0, sizeof(sense));
 	rq->sense = sense;
 	rq->sense_len = 0;
-	blk_rq_set_block_pc(rq);
 
 	blk_execute_rq(q, disk, rq, 0);
 
@@ -521,7 +534,8 @@ out:
 	
 error:
 	kfree(buffer);
-	blk_put_request(rq);
+	if (rq)
+		blk_put_request(rq);
 	return err;
 }
 EXPORT_SYMBOL_GPL(sg_scsi_ioctl);