scsi: convert discard to REQ_TYPE_FS from REQ_TYPE_BLOCK_PC
Jens, any reason why this isn't included in your for-2.6.36 yet?
=
From: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Subject: [PATCH resend] scsi: convert discard to REQ_TYPE_FS from REQ_TYPE_BLOCK_PC
The block layer (file systems) sends discard requests as REQ_TYPE_FS
(the role of REQ_TYPE_FS is that setting up commands and interpreting
the results). But SCSI-ml treats discard requests as
REQ_TYPE_BLOCK_PC.
scsi-ml can handle discard requests as REQ_TYPE_FS
easily. scsi_setup_discard_cmnd() sets up struct request and the bio
nicely. Only remaining issue is that discard requests can't be
completed partially so we need to modify sd_done.
This conversion also fixes the problem that discard requests aren't
retried when possible (e.g. UNIT ATTENTION).
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index fc5d69a..e63b85a 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -434,7 +434,6 @@
nr_sectors >>= 3;
}
- rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->timeout = SD_TIMEOUT;
memset(rq->cmd, 0, rq->cmd_len);
@@ -1200,6 +1199,12 @@
int sense_valid = 0;
int sense_deferred = 0;
+ if (SCpnt->request->cmd_flags & REQ_DISCARD) {
+ if (!result)
+ scsi_set_resid(SCpnt, 0);
+ return good_bytes;
+ }
+
if (result) {
sense_valid = scsi_command_normalize_sense(SCpnt, &sshdr);
if (sense_valid)