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author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-09-23 14:45:09 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-09-23 14:45:09 -0700 |
commit | 31f9bf46a5bb5773b3b3cb4719a7f91f64f540e8 (patch) | |
tree | d1a0762b2986cbe7112814d1e36eb610edf87586 | |
parent | d19eff3acfd27dead12ff1f7255fbfea2d778cdb (diff) | |
parent | 46f341ffcfb5d8530f7d1e60f3be06cce6661b62 (diff) | |
download | op-kernel-dev-31f9bf46a5bb5773b3b3cb4719a7f91f64f540e8.zip op-kernel-dev-31f9bf46a5bb5773b3b3cb4719a7f91f64f540e8.tar.gz |
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull final block fixes from Jens Axboe:
"This week and last we've been fixing some corner cases related to
blk-mq, mostly. I ended up pulling most of that out of for-linus
yesterday, which is why the branch looks fresh. The rest were
postponed for 3.18.
This pull request contains:
- Fix from Christoph, avoiding a stack overflow when FUA insertion
would recursive infinitely.
- Fix from David Hildenbrand on races between the timeout handler and
uninitialized requests. Fixes a real issue that virtio_blk has run
into.
- A few fixes from me:
- Ensure that request deadline/timeout is ordered before the
request is marked as started.
- A potential oops on out-of-memory, when we scale the queue
depth of the device and retry.
- A hang fix on requeue from SCSI, where the hardware queue
would be stopped when we attempt to re-run it (and hence
nothing would happen, stalling progress).
- A fix for commit 2da78092, where the cleanup path was moved
to RCU, but a debug might_sleep() was inadvertently left in
the code. This causes warnings for people"
* 'for-linus' of git://git.kernel.dk/linux-block:
genhd: fix leftover might_sleep() in blk_free_devt()
blk-mq: use blk_mq_start_hw_queues() when running requeue work
blk-mq: fix potential oops on out-of-memory in __blk_mq_alloc_rq_maps()
blk-mq: avoid infinite recursion with the FUA flag
blk-mq: Avoid race condition with uninitialized requests
blk-mq: request deadline must be visible before marking rq as started
-rw-r--r-- | block/blk-exec.c | 1 | ||||
-rw-r--r-- | block/blk-mq.c | 28 | ||||
-rw-r--r-- | block/genhd.c | 2 |
3 files changed, 18 insertions, 13 deletions
diff --git a/block/blk-exec.c b/block/blk-exec.c index f4d27b1..9924725 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -56,6 +56,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, bool is_pm_resume; WARN_ON(irqs_disabled()); + WARN_ON(rq->cmd_type == REQ_TYPE_FS); rq->rq_disk = bd_disk; rq->end_io = done; diff --git a/block/blk-mq.c b/block/blk-mq.c index 383ea0c..c88e608 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -203,7 +203,6 @@ __blk_mq_alloc_request(struct blk_mq_alloc_data *data, int rw) if (tag != BLK_MQ_TAG_FAIL) { rq = data->hctx->tags->rqs[tag]; - rq->cmd_flags = 0; if (blk_mq_tag_busy(data->hctx)) { rq->cmd_flags = REQ_MQ_INFLIGHT; atomic_inc(&data->hctx->nr_active); @@ -258,6 +257,7 @@ static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx, if (rq->cmd_flags & REQ_MQ_INFLIGHT) atomic_dec(&hctx->nr_active); + rq->cmd_flags = 0; clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags); blk_mq_put_tag(hctx, tag, &ctx->last_tag); @@ -393,6 +393,12 @@ static void blk_mq_start_request(struct request *rq, bool last) blk_add_timer(rq); /* + * Ensure that ->deadline is visible before set the started + * flag and clear the completed flag. + */ + smp_mb__before_atomic(); + + /* * Mark us as started and clear complete. Complete might have been * set if requeue raced with timeout, which then marked it as * complete. So be sure to clear complete again when we start @@ -473,7 +479,11 @@ static void blk_mq_requeue_work(struct work_struct *work) blk_mq_insert_request(rq, false, false, false); } - blk_mq_run_queues(q, false); + /* + * Use the start variant of queue running here, so that running + * the requeue work will kick stopped queues. + */ + blk_mq_start_hw_queues(q); } void blk_mq_add_to_requeue_list(struct request *rq, bool at_head) @@ -957,14 +967,9 @@ void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue, hctx = q->mq_ops->map_queue(q, ctx->cpu); - if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA) && - !(rq->cmd_flags & (REQ_FLUSH_SEQ))) { - blk_insert_flush(rq); - } else { - spin_lock(&ctx->lock); - __blk_mq_insert_request(hctx, rq, at_head); - spin_unlock(&ctx->lock); - } + spin_lock(&ctx->lock); + __blk_mq_insert_request(hctx, rq, at_head); + spin_unlock(&ctx->lock); if (run_queue) blk_mq_run_hw_queue(hctx, async); @@ -1404,6 +1409,8 @@ static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set, left -= to_do * rq_size; for (j = 0; j < to_do; j++) { tags->rqs[i] = p; + tags->rqs[i]->atomic_flags = 0; + tags->rqs[i]->cmd_flags = 0; if (set->ops->init_request) { if (set->ops->init_request(set->driver_data, tags->rqs[i], hctx_idx, i, @@ -1956,7 +1963,6 @@ out_unwind: while (--i >= 0) blk_mq_free_rq_map(set, set->tags[i], i); - set->tags = NULL; return -ENOMEM; } diff --git a/block/genhd.c b/block/genhd.c index 09da5e4..e6723bd 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -445,8 +445,6 @@ int blk_alloc_devt(struct hd_struct *part, dev_t *devt) */ void blk_free_devt(dev_t devt) { - might_sleep(); - if (devt == MKDEV(0, 0)) return; |