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| author | Joe Lawrence <joe.lawrence@stratus.com> | 2014-08-28 08:15:21 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2014-08-28 10:03:46 -0600 |
| commit | a492f075450f3ba87de36e5ffe92a9d0c7af9723 (patch) | |
| tree | 61960a71c7fde0eee3d77cda460154d2f7715d2f /drivers/block | |
| parent | eb571eeade2598635f813b3284d02c13a380301e (diff) | |
| download | linux-a492f075450f3ba87de36e5ffe92a9d0c7af9723.tar.gz linux-a492f075450f3ba87de36e5ffe92a9d0c7af9723.tar.bz2 linux-a492f075450f3ba87de36e5ffe92a9d0c7af9723.zip | |
block,scsi: fixup blk_get_request dead queue scenarios
The blk_get_request function may fail in low-memory conditions or during
device removal (even if __GFP_WAIT is set). To distinguish between these
errors, modify the blk_get_request call stack to return the appropriate
ERR_PTR. Verify that all callers check the return status and consider
IS_ERR instead of a simple NULL pointer check.
For consistency, make a similar change to the blk_mq_alloc_request leg
of blk_get_request. It may fail if the queue is dead, or the caller was
unwilling to wait.
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd]
Acked-by: Boaz Harrosh <bharrosh@panasas.com> [for osd]
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/paride/pd.c | 4 | ||||
| -rw-r--r-- | drivers/block/pktcdvd.c | 4 | ||||
| -rw-r--r-- | drivers/block/sx8.c | 2 |
3 files changed, 5 insertions, 5 deletions
diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c index ca831f741d89..d48715b287e6 100644 --- a/drivers/block/paride/pd.c +++ b/drivers/block/paride/pd.c @@ -722,8 +722,8 @@ static int pd_special_command(struct pd_unit *disk, int err = 0; rq = blk_get_request(disk->gd->queue, READ, __GFP_WAIT); - if (!rq) - return -ENODEV; + if (IS_ERR(rq)) + return PTR_ERR(rq); rq->cmd_type = REQ_TYPE_SPECIAL; rq->special = func; diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index 7fa8c80e8982..09e628dafd9d 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -704,8 +704,8 @@ static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command * rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ, __GFP_WAIT); - if (!rq) - return -ENODEV; + if (IS_ERR(rq)) + return PTR_ERR(rq); blk_rq_set_block_pc(rq); if (cgc->buflen) { diff --git a/drivers/block/sx8.c b/drivers/block/sx8.c index d5e2d12b9d9e..5d552857de41 100644 --- a/drivers/block/sx8.c +++ b/drivers/block/sx8.c @@ -568,7 +568,7 @@ static struct carm_request *carm_get_special(struct carm_host *host) return NULL; rq = blk_get_request(host->oob_q, WRITE /* bogus */, GFP_KERNEL); - if (!rq) { + if (IS_ERR(rq)) { spin_lock_irqsave(&host->lock, flags); carm_put_request(host, crq); spin_unlock_irqrestore(&host->lock, flags); |