block: fix error handling in sg_io

Before commit 2cada584b200 ("block: cleanup error handling in sg_io"),
we had ret = 0 before entering the last big if block of sg_io.

Since 2cada584b200, ret = -EFAULT, which breaks hdparm:

/dev/sda:
 setting Advanced Power Management level to 0xc8 (200)
 HDIO_DRIVE_CMD failed: Bad address
 APM_level      = 128

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: 2cada584b200 ("block: cleanup error handling in sg_io")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 5dd477b..9b8eaec 100644 (file)
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -330,6 +330,7 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
        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;