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authorLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 15:32:19 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2017-11-14 15:32:19 -0800
commite2c5923c349c1738fe8fda980874d93f6fb2e5b6 (patch)
treeb97a90170c45211bcc437761653aa8016c34afcd /block
parentabc36be236358162202e86ad88616ff95a755101 (diff)
parenta04b5de5050ab8b891128eb2c47a0916fe8622e1 (diff)
downloadlinux-stericsson-e2c5923c349c1738fe8fda980874d93f6fb2e5b6.tar.gz
Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block
Pull core block layer updates from Jens Axboe: "This is the main pull request for block storage for 4.15-rc1. Nothing out of the ordinary in here, and no API changes or anything like that. Just various new features for drivers, core changes, etc. In particular, this pull request contains: - A patch series from Bart, closing the whole on blk/scsi-mq queue quescing. - A series from Christoph, building towards hidden gendisks (for multipath) and ability to move bio chains around. - NVMe - Support for native multipath for NVMe (Christoph). - Userspace notifications for AENs (Keith). - Command side-effects support (Keith). - SGL support (Chaitanya Kulkarni) - FC fixes and improvements (James Smart) - Lots of fixes and tweaks (Various) - bcache - New maintainer (Michael Lyle) - Writeback control improvements (Michael) - Various fixes (Coly, Elena, Eric, Liang, et al) - lightnvm updates, mostly centered around the pblk interface (Javier, Hans, and Rakesh). - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph) - Writeback series that fix the much discussed hundreds of millions of sync-all units. This goes all the way, as discussed previously (me). - Fix for missing wakeup on writeback timer adjustments (Yafang Shao). - Fix laptop mode on blk-mq (me). - {mq,name} tupple lookup for IO schedulers, allowing us to have alias names. This means you can use 'deadline' on both !mq and on mq (where it's called mq-deadline). (me). - blktrace race fix, oopsing on sg load (me). - blk-mq optimizations (me). - Obscure waitqueue race fix for kyber (Omar). - NBD fixes (Josef). - Disable writeback throttling by default on bfq, like we do on cfq (Luca Miccio). - Series from Ming that enable us to treat flush requests on blk-mq like any other request. This is a really nice cleanup. - Series from Ming that improves merging on blk-mq with schedulers, getting us closer to flipping the switch on scsi-mq again. - BFQ updates (Paolo). - blk-mq atomic flags memory ordering fixes (Peter Z). - Loop cgroup support (Shaohua). - Lots of minor fixes from lots of different folks, both for core and driver code" * 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits) nvme: fix visibility of "uuid" ns attribute blk-mq: fixup some comment typos and lengths ide: ide-atapi: fix compile error with defining macro DEBUG blk-mq: improve tag waiting setup for non-shared tags brd: remove unused brd_mutex blk-mq: only run the hardware queue if IO is pending block: avoid null pointer dereference on null disk fs: guard_bio_eod() needs to consider partitions xtensa/simdisk: fix compile error nvme: expose subsys attribute to sysfs nvme: create 'slaves' and 'holders' entries for hidden controllers block: create 'slaves' and 'holders' entries for hidden gendisks nvme: also expose the namespace identification sysfs files for mpath nodes nvme: implement multipath access to nvme subsystems nvme: track shared namespaces nvme: introduce a nvme_ns_ids structure nvme: track subsystems block, nvme: Introduce blk_mq_req_flags_t block, scsi: Make SCSI quiesce and resume work reliably block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag ...
Diffstat (limited to 'block')
-rw-r--r--block/bfq-iosched.c225
-rw-r--r--block/bio-integrity.c7
-rw-r--r--block/bio.c40
-rw-r--r--block/blk-cgroup.c9
-rw-r--r--block/blk-core.c274
-rw-r--r--block/blk-flush.c37
-rw-r--r--block/blk-lib.c108
-rw-r--r--block/blk-mq-debugfs.c3
-rw-r--r--block/blk-mq-sched.c203
-rw-r--r--block/blk-mq-tag.c11
-rw-r--r--block/blk-mq-tag.h7
-rw-r--r--block/blk-mq.c422
-rw-r--r--block/blk-mq.h60
-rw-r--r--block/blk-settings.c2
-rw-r--r--block/blk-stat.c45
-rw-r--r--block/blk-throttle.c12
-rw-r--r--block/blk-timeout.c5
-rw-r--r--block/blk-wbt.c2
-rw-r--r--block/blk.h46
-rw-r--r--block/bsg.c18
-rw-r--r--block/elevator.c67
-rw-r--r--block/genhd.c70
-rw-r--r--block/ioctl.c19
-rw-r--r--block/kyber-iosched.c12
-rw-r--r--block/mq-deadline.c1
-rw-r--r--block/scsi_ioctl.c8
26 files changed, 1097 insertions, 616 deletions
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index a4783da90ba8..889a8549d97f 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -108,6 +108,7 @@
#include "blk-mq-tag.h"
#include "blk-mq-sched.h"
#include "bfq-iosched.h"
+#include "blk-wbt.h"
#define BFQ_BFQQ_FNS(name) \
void bfq_mark_bfqq_##name(struct bfq_queue *bfqq) \
@@ -724,6 +725,44 @@ static void bfq_updated_next_req(struct bfq_data *bfqd,
}
}
+static unsigned int bfq_wr_duration(struct bfq_data *bfqd)
+{
+ u64 dur;
+
+ if (bfqd->bfq_wr_max_time > 0)
+ return bfqd->bfq_wr_max_time;
+
+ dur = bfqd->RT_prod;
+ do_div(dur, bfqd->peak_rate);
+
+ /*
+ * Limit duration between 3 and 13 seconds. Tests show that
+ * higher values than 13 seconds often yield the opposite of
+ * the desired result, i.e., worsen responsiveness by letting
+ * non-interactive and non-soft-real-time applications
+ * preserve weight raising for a too long time interval.
+ *
+ * On the other end, lower values than 3 seconds make it
+ * difficult for most interactive tasks to complete their jobs
+ * before weight-raising finishes.
+ */
+ if (dur > msecs_to_jiffies(13000))
+ dur = msecs_to_jiffies(13000);
+ else if (dur < msecs_to_jiffies(3000))
+ dur = msecs_to_jiffies(3000);
+
+ return dur;
+}
+
+/* switch back from soft real-time to interactive weight raising */
+static void switch_back_to_interactive_wr(struct bfq_queue *bfqq,
+ struct bfq_data *bfqd)
+{
+ bfqq->wr_coeff = bfqd->bfq_wr_coeff;
+ bfqq->wr_cur_max_time = bfq_wr_duration(bfqd);
+ bfqq->last_wr_start_finish = bfqq->wr_start_at_switch_to_srt;
+}
+
static void
bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_data *bfqd,
struct bfq_io_cq *bic, bool bfq_already_existing)
@@ -750,10 +789,16 @@ bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_data *bfqd,
if (bfqq->wr_coeff > 1 && (bfq_bfqq_in_large_burst(bfqq) ||
time_is_before_jiffies(bfqq->last_wr_start_finish +
bfqq->wr_cur_max_time))) {
- bfq_log_bfqq(bfqq->bfqd, bfqq,
- "resume state: switching off wr");
-
- bfqq->wr_coeff = 1;
+ if (bfqq->wr_cur_max_time == bfqd->bfq_wr_rt_max_time &&
+ !bfq_bfqq_in_large_burst(bfqq) &&
+ time_is_after_eq_jiffies(bfqq->wr_start_at_switch_to_srt +
+ bfq_wr_duration(bfqd))) {
+ switch_back_to_interactive_wr(bfqq, bfqd);
+ } else {
+ bfqq->wr_coeff = 1;
+ bfq_log_bfqq(bfqq->bfqd, bfqq,
+ "resume state: switching off wr");
+ }
}
/* make sure weight will be updated, however we got here */
@@ -1173,33 +1218,22 @@ static bool bfq_bfqq_update_budg_for_activation(struct bfq_data *bfqd,
return wr_or_deserves_wr;
}
-static unsigned int bfq_wr_duration(struct bfq_data *bfqd)
+/*
+ * Return the farthest future time instant according to jiffies
+ * macros.
+ */
+static unsigned long bfq_greatest_from_now(void)
{
- u64 dur;
-
- if (bfqd->bfq_wr_max_time > 0)
- return bfqd->bfq_wr_max_time;
-
- dur = bfqd->RT_prod;
- do_div(dur, bfqd->peak_rate);
-
- /*
- * Limit duration between 3 and 13 seconds. Tests show that
- * higher values than 13 seconds often yield the opposite of
- * the desired result, i.e., worsen responsiveness by letting
- * non-interactive and non-soft-real-time applications
- * preserve weight raising for a too long time interval.
- *
- * On the other end, lower values than 3 seconds make it
- * difficult for most interactive tasks to complete their jobs
- * before weight-raising finishes.
- */
- if (dur > msecs_to_jiffies(13000))
- dur = msecs_to_jiffies(13000);
- else if (dur < msecs_to_jiffies(3000))
- dur = msecs_to_jiffies(3000);
+ return jiffies + MAX_JIFFY_OFFSET;
+}
- return dur;
+/*
+ * Return the farthest past time instant according to jiffies
+ * macros.
+ */
+static unsigned long bfq_smallest_from_now(void)
+{
+ return jiffies - MAX_JIFFY_OFFSET;
}
static void bfq_update_bfqq_wr_on_rq_arrival(struct bfq_data *bfqd,
@@ -1216,7 +1250,19 @@ static void bfq_update_bfqq_wr_on_rq_arrival(struct bfq_data *bfqd,
bfqq->wr_coeff = bfqd->bfq_wr_coeff;
bfqq->wr_cur_max_time = bfq_wr_duration(bfqd);
} else {
- bfqq->wr_start_at_switch_to_srt = jiffies;
+ /*
+ * No interactive weight raising in progress
+ * here: assign minus infinity to
+ * wr_start_at_switch_to_srt, to make sure
+ * that, at the end of the soft-real-time
+ * weight raising periods that is starting
+ * now, no interactive weight-raising period
+ * may be wrongly considered as still in
+ * progress (and thus actually started by
+ * mistake).
+ */
+ bfqq->wr_start_at_switch_to_srt =
+ bfq_smallest_from_now();
bfqq->wr_coeff = bfqd->bfq_wr_coeff *
BFQ_SOFTRT_WEIGHT_FACTOR;
bfqq->wr_cur_max_time =
@@ -2016,10 +2062,27 @@ static void bfq_bfqq_save_state(struct bfq_queue *bfqq)
bic->saved_IO_bound = bfq_bfqq_IO_bound(bfqq);
bic->saved_in_large_burst = bfq_bfqq_in_large_burst(bfqq);
bic->was_in_burst_list = !hlist_unhashed(&bfqq->burst_list_node);
- bic->saved_wr_coeff = bfqq->wr_coeff;
- bic->saved_wr_start_at_switch_to_srt = bfqq->wr_start_at_switch_to_srt;
- bic->saved_last_wr_start_finish = bfqq->last_wr_start_finish;
- bic->saved_wr_cur_max_time = bfqq->wr_cur_max_time;
+ if (unlikely(bfq_bfqq_just_created(bfqq) &&
+ !bfq_bfqq_in_large_burst(bfqq))) {
+ /*
+ * bfqq being merged right after being created: bfqq
+ * would have deserved interactive weight raising, but
+ * did not make it to be set in a weight-raised state,
+ * because of this early merge. Store directly the
+ * weight-raising state that would have been assigned
+ * to bfqq, so that to avoid that bfqq unjustly fails
+ * to enjoy weight raising if split soon.
+ */
+ bic->saved_wr_coeff = bfqq->bfqd->bfq_wr_coeff;
+ bic->saved_wr_cur_max_time = bfq_wr_duration(bfqq->bfqd);
+ bic->saved_last_wr_start_finish = jiffies;
+ } else {
+ bic->saved_wr_coeff = bfqq->wr_coeff;
+ bic->saved_wr_start_at_switch_to_srt =
+ bfqq->wr_start_at_switch_to_srt;
+ bic->saved_last_wr_start_finish = bfqq->last_wr_start_finish;
+ bic->saved_wr_cur_max_time = bfqq->wr_cur_max_time;
+ }
}
static void
@@ -2897,24 +2960,6 @@ static unsigned long bfq_bfqq_softrt_next_start(struct bfq_data *bfqd,
jiffies + nsecs_to_jiffies(bfqq->bfqd->bfq_slice_idle) + 4);
}
-/*
- * Return the farthest future time instant according to jiffies
- * macros.
- */
-static unsigned long bfq_greatest_from_now(void)
-{
- return jiffies + MAX_JIFFY_OFFSET;
-}
-
-/*
- * Return the farthest past time instant according to jiffies
- * macros.
- */
-static unsigned long bfq_smallest_from_now(void)
-{
- return jiffies - MAX_JIFFY_OFFSET;
-}
-
/**
* bfq_bfqq_expire - expire a queue.
* @bfqd: device owning the queue.
@@ -3489,11 +3534,7 @@ static void bfq_update_wr_data(struct bfq_data *bfqd, struct bfq_queue *bfqq)
bfq_wr_duration(bfqd)))
bfq_bfqq_end_wr(bfqq);
else {
- /* switch back to interactive wr */
- bfqq->wr_coeff = bfqd->bfq_wr_coeff;
- bfqq->wr_cur_max_time = bfq_wr_duration(bfqd);
- bfqq->last_wr_start_finish =
- bfqq->wr_start_at_switch_to_srt;
+ switch_back_to_interactive_wr(bfqq, bfqd);
bfqq->entity.prio_changed = 1;
}
}
@@ -3685,16 +3726,37 @@ void bfq_put_queue(struct bfq_queue *bfqq)
if (bfqq->ref)
return;
- if (bfq_bfqq_sync(bfqq))
+ if (!hlist_unhashed(&bfqq->burst_list_node)) {
+ hlist_del_init(&bfqq->burst_list_node);
/*
- * The fact that this queue is being destroyed does not
- * invalidate the fact that this queue may have been
- * activated during the current burst. As a consequence,
- * although the queue does not exist anymore, and hence
- * needs to be removed from the burst list if there,
- * the burst size has not to be decremented.
+ * Decrement also burst size after the removal, if the
+ * process associated with bfqq is exiting, and thus
+ * does not contribute to the burst any longer. This
+ * decrement helps filter out false positives of large
+ * bursts, when some short-lived process (often due to
+ * the execution of commands by some service) happens
+ * to start and exit while a complex application is
+ * starting, and thus spawning several processes that
+ * do I/O (and that *must not* be treated as a large
+ * burst, see comments on bfq_handle_burst).
+ *
+ * In particular, the decrement is performed only if:
+ * 1) bfqq is not a merged queue, because, if it is,
+ * then this free of bfqq is not triggered by the exit
+ * of the process bfqq is associated with, but exactly
+ * by the fact that bfqq has just been merged.
+ * 2) burst_size is greater than 0, to handle
+ * unbalanced decrements. Unbalanced decrements may
+ * happen in te following case: bfqq is inserted into
+ * the current burst list--without incrementing
+ * bust_size--because of a split, but the current
+ * burst list is not the burst list bfqq belonged to
+ * (see comments on the case of a split in
+ * bfq_set_request).
*/
- hlist_del_init(&bfqq->burst_list_node);
+ if (bfqq->bic && bfqq->bfqd->burst_size > 0)
+ bfqq->bfqd->burst_size--;
+ }
kmem_cache_free(bfq_pool, bfqq);
#ifdef CONFIG_BFQ_GROUP_IOSCHED
@@ -4127,7 +4189,6 @@ static void __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
new_bfqq->allocated++;
bfqq->allocated--;
new_bfqq->ref++;
- bfq_clear_bfqq_just_created(bfqq);
/*
* If the bic associated with the process
* issuing this request still points to bfqq
@@ -4139,6 +4200,8 @@ static void __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
if (bic_to_bfqq(RQ_BIC(rq), 1) == bfqq)
bfq_merge_bfqqs(bfqd, RQ_BIC(rq),
bfqq, new_bfqq);
+
+ bfq_clear_bfqq_just_created(bfqq);
/*
* rq is about to be enqueued into new_bfqq,
* release rq reference on bfqq
@@ -4424,6 +4487,34 @@ static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd,
else {
bfq_clear_bfqq_in_large_burst(bfqq);
if (bic->was_in_burst_list)
+ /*
+ * If bfqq was in the current
+ * burst list before being
+ * merged, then we have to add
+ * it back. And we do not need
+ * to increase burst_size, as
+ * we did not decrement
+ * burst_size when we removed
+ * bfqq from the burst list as
+ * a consequence of a merge
+ * (see comments in
+ * bfq_put_queue). In this
+ * respect, it would be rather
+ * costly to know whether the
+ * current burst list is still
+ * the same burst list from
+ * which bfqq was removed on
+ * the merge. To avoid this
+ * cost, if bfqq was in a
+ * burst list, then we add
+ * bfqq to the current burst
+ * list without any further
+ * check. This can cause
+ * inappropriate insertions,
+ * but rarely enough to not
+ * harm the detection of large
+ * bursts significantly.
+ */
hlist_add_head(&bfqq->burst_list_node,
&bfqd->burst_list);
}
@@ -4775,7 +4866,7 @@ static int bfq_init_queue(struct request_queue *q, struct elevator_type *e)
bfq_init_root_group(bfqd->root_group, bfqd);
bfq_init_entity(&bfqd->oom_bfqq.entity, bfqd->root_group);
-
+ wbt_disable_default(q);
return 0;
out_free:
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 5df32907ff3b..23b42e8aa03e 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -485,11 +485,8 @@ EXPORT_SYMBOL(bioset_integrity_create);
void bioset_integrity_free(struct bio_set *bs)
{
- if (bs->bio_integrity_pool)
- mempool_destroy(bs->bio_integrity_pool);
-
- if (bs->bvec_integrity_pool)
- mempool_destroy(bs->bvec_integrity_pool);
+ mempool_destroy(bs->bio_integrity_pool);
+ mempool_destroy(bs->bvec_integrity_pool);
}
EXPORT_SYMBOL(bioset_integrity_free);
diff --git a/block/bio.c b/block/bio.c
index cc60213e56d8..b94a802f8ba3 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -400,7 +400,7 @@ static void punt_bios_to_rescuer(struct bio_set *bs)
/**
* bio_alloc_bioset - allocate a bio for I/O
- * @gfp_mask: the GFP_ mask given to the slab allocator
+ * @gfp_mask: the GFP_* mask given to the slab allocator
* @nr_iovecs: number of iovecs to pre-allocate
* @bs: the bio_set to allocate from.
*
@@ -1931,11 +1931,8 @@ void bioset_free(struct bio_set *bs)
if (bs->rescue_workqueue)
destroy_workqueue(bs->rescue_workqueue);
- if (bs->bio_pool)
- mempool_destroy(bs->bio_pool);
-
- if (bs->bvec_pool)
- mempool_destroy(bs->bvec_pool);
+ mempool_destroy(bs->bio_pool);
+ mempool_destroy(bs->bvec_pool);
bioset_integrity_free(bs);
bio_put_slab(bs);
@@ -2036,37 +2033,6 @@ int bio_associate_blkcg(struct bio *bio, struct cgroup_subsys_state *blkcg_css)
EXPORT_SYMBOL_GPL(bio_associate_blkcg);
/**
- * bio_associate_current - associate a bio with %current
- * @bio: target bio
- *
- * Associate @bio with %current if it hasn't been associated yet. Block
- * layer will treat @bio as if it were issued by %current no matter which
- * task actually issues it.
- *
- * This function takes an extra reference of @task's io_context and blkcg
- * which will be put when @bio is released. The caller must own @bio,
- * ensure %current->io_context exists, and is responsible for synchronizing
- * calls to this function.
- */
-int bio_associate_current(struct bio *bio)
-{
- struct io_context *ioc;
-
- if (bio->bi_css)
- return -EBUSY;
-
- ioc = current->io_context;
- if (!ioc)
- return -ENOENT;
-
- get_io_context_active(ioc);
- bio->bi_ioc = ioc;
- bio->bi_css = task_get_css(current, io_cgrp_id);
- return 0;
-}
-EXPORT_SYMBOL_GPL(bio_associate_current);
-
-/**
* bio_disassociate_task - undo bio_associate_current()
* @bio: target bio
*/
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index d3f56baee936..4117524ca45b 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1419,6 +1419,11 @@ int blkcg_policy_register(struct blkcg_policy *pol)
if (i >= BLKCG_MAX_POLS)
goto err_unlock;
+ /* Make sure cpd/pd_alloc_fn and cpd/pd_free_fn in pairs */
+ if ((!pol->cpd_alloc_fn ^ !pol->cpd_free_fn) ||
+ (!pol->pd_alloc_fn ^ !pol->pd_free_fn))
+ goto err_unlock;
+
/* register @pol */
pol->plid = i;
blkcg_policy[pol->plid] = pol;
@@ -1452,7 +1457,7 @@ int blkcg_policy_register(struct blkcg_policy *pol)
return 0;
err_free_cpds:
- if (pol->cpd_alloc_fn) {
+ if (pol->cpd_free_fn) {
list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) {
if (blkcg->cpd[pol->plid]) {
pol->cpd_free_fn(blkcg->cpd[pol->plid]);
@@ -1492,7 +1497,7 @@ void blkcg_policy_unregister(struct blkcg_policy *pol)
/* remove cpds and unregister */
mutex_lock(&blkcg_pol_mutex);
- if (pol->cpd_alloc_fn) {
+ if (pol->cpd_free_fn) {
list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) {
if (blkcg->cpd[pol->plid]) {
pol->cpd_free_fn(blkcg->cpd[pol->plid]);
diff --git a/block/blk-core.c b/block/blk-core.c
index 048be4aa6024..7c54c195e79e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -333,11 +333,13 @@ EXPORT_SYMBOL(blk_stop_queue);
void blk_sync_queue(struct request_queue *q)
{
del_timer_sync(&q->timeout);
+ cancel_work_sync(&q->timeout_work);
if (q->mq_ops) {
struct blk_mq_hw_ctx *hctx;
int i;
+ cancel_delayed_work_sync(&q->requeue_work);
queue_for_each_hw_ctx(q, hctx, i)
cancel_delayed_work_sync(&hctx->run_work);
} else {
@@ -347,6 +349,37 @@ void blk_sync_queue(struct request_queue *q)
EXPORT_SYMBOL(blk_sync_queue);
/**
+ * blk_set_preempt_only - set QUEUE_FLAG_PREEMPT_ONLY
+ * @q: request queue pointer
+ *
+ * Returns the previous value of the PREEMPT_ONLY flag - 0 if the flag was not
+ * set and 1 if the flag was already set.
+ */
+int blk_set_preempt_only(struct request_queue *q)
+{
+ unsigned long flags;
+ int res;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ res = queue_flag_test_and_set(QUEUE_FLAG_PREEMPT_ONLY, q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ return res;
+}
+EXPORT_SYMBOL_GPL(blk_set_preempt_only);
+
+void blk_clear_preempt_only(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ queue_flag_clear(QUEUE_FLAG_PREEMPT_ONLY, q);
+ wake_up_all(&q->mq_freeze_wq);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+EXPORT_SYMBOL_GPL(blk_clear_preempt_only);
+
+/**
* __blk_run_queue_uncond - run a queue whether or not it has been stopped
* @q: The queue to run
*
@@ -610,6 +643,9 @@ void blk_set_queue_dying(struct request_queue *q)
}
spin_unlock_irq(q->queue_lock);
}
+
+ /* Make blk_queue_enter() reexamine the DYING flag. */
+ wake_up_all(&q->mq_freeze_wq);
}
EXPORT_SYMBOL_GPL(blk_set_queue_dying);
@@ -718,7 +754,7 @@ static void free_request_size(void *element, void *data)
int blk_init_rl(struct request_list *rl, struct request_queue *q,
gfp_t gfp_mask)
{
- if (unlikely(rl->rq_pool))
+ if (unlikely(rl->rq_pool) || q->mq_ops)
return 0;
rl->q = q;
@@ -760,15 +796,38 @@ struct request_queue *blk_alloc_queue(gfp_t gfp_mask)
}
EXPORT_SYMBOL(blk_alloc_queue);
-int blk_queue_enter(struct request_queue *q, bool nowait)
+/**
+ * blk_queue_enter() - try to increase q->q_usage_counter
+ * @q: request queue pointer
+ * @flags: BLK_MQ_REQ_NOWAIT and/or BLK_MQ_REQ_PREEMPT
+ */
+int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
{
+ const bool preempt = flags & BLK_MQ_REQ_PREEMPT;
+
while (true) {
+ bool success = false;
int ret;
- if (percpu_ref_tryget_live(&q->q_usage_counter))
+ rcu_read_lock_sched();
+ if (percpu_ref_tryget_live(&q->q_usage_counter)) {
+ /*
+ * The code that sets the PREEMPT_ONLY flag is
+ * responsible for ensuring that that flag is globally
+ * visible before the queue is unfrozen.
+ */
+ if (preempt || !blk_queue_preempt_only(q)) {
+ success = true;
+ } else {
+ percpu_ref_put(&q->q_usage_counter);
+ }
+ }
+ rcu_read_unlock_sched();
+
+ if (success)
return 0;
- if (nowait)
+ if (flags & BLK_MQ_REQ_NOWAIT)
return -EBUSY;
/*
@@ -781,7 +840,8 @@ int blk_queue_enter(struct request_queue *q, bool nowait)
smp_rmb();
ret = wait_event_interruptible(q->mq_freeze_wq,
- !atomic_read(&q->mq_freeze_depth) ||
+ (atomic_read(&q->mq_freeze_depth) == 0 &&
+ (preempt || !blk_queue_preempt_only(q))) ||
blk_queue_dying(q));
if (blk_queue_dying(q))
return -ENODEV;
@@ -844,6 +904,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
setup_timer(&q->backing_dev_info->laptop_mode_wb_timer,
laptop_mode_timer_fn, (unsigned long) q);
setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q);
+ INIT_WORK(&q->timeout_work, NULL);
INIT_LIST_HEAD(&q->queue_head);
INIT_LIST_HEAD(&q->timeout_list);
INIT_LIST_HEAD(&q->icq_list);
@@ -1154,7 +1215,7 @@ int blk_update_nr_requests(struct request_queue *q, unsigned int nr)
* @rl: request list to allocate from
* @op: operation and flags
* @bio: bio to allocate request for (can be %NULL)
- * @gfp_mask: allocation mask
+ * @flags: BLQ_MQ_REQ_* flags
*
* Get a free request from @q. This function may fail under memory
* pressure or if @q is dead.
@@ -1164,7 +1225,7 @@ int blk_update_nr_requests(struct request_queue *q, unsigned int nr)
* Returns request pointer on success, with @q->queue_lock *not held*.
*/
static struct request *__get_request(struct request_list *rl, unsigned int op,
- struct bio *bio, gfp_t gfp_mask)
+ struct bio *bio, blk_mq_req_flags_t flags)
{
struct request_queue *q = rl->q;
struct request *rq;
@@ -1173,6 +1234,8 @@ static struct request *__get_request(struct request_list *rl, unsigned int op,
struct io_cq *icq = NULL;
const bool is_sync = op_is_sync(op);
int may_queue;
+ gfp_t gfp_mask = flags & BLK_MQ_REQ_NOWAIT ? GFP_ATOMIC :
+ __GFP_DIRECT_RECLAIM;
req_flags_t rq_flags = RQF_ALLOCED;
lockdep_assert_held(q->queue_lock);
@@ -1255,6 +1318,8 @@ static struct request *__get_request(struct request_list *rl, unsigned int op,
blk_rq_set_rl(rq, rl);
rq->cmd_flags = op;
rq->rq_flags = rq_flags;
+ if (flags & BLK_MQ_REQ_PREEMPT)
+ rq->rq_flags |= RQF_PREEMPT;
/* init elvpriv */
if (rq_flags & RQF_ELVPRIV) {
@@ -1333,7 +1398,7 @@ rq_starved:
* @q: request_queue to allocate request from
* @op: operation and flags
* @bio: bio to allocate request for (can be %NULL)
- * @gfp_mask: allocation mask
+ * @flags: BLK_MQ_REQ_* flags.
*
* Get a free request from @q. If %__GFP_DIRECT_RECLAIM is set in @gfp_mask,
* this function keeps retrying under memory pressure and fails iff @q is dead.
@@ -1343,7 +1408,7 @@ rq_starved:
* Returns request pointer on success, with @q->queue_lock *not held*.
*/
static struct request *get_request(struct request_queue *q, unsigned int op,
- struct bio *bio, gfp_t gfp_mask)
+ struct bio *bio, blk_mq_req_flags_t flags)
{
const bool is_sync = op_is_sync(op);
DEFINE_WAIT(wait);
@@ -1355,7 +1420,7 @@ static struct request *get_request(struct request_queue *q, unsigned int op,
rl = blk_get_rl(q, bio); /* transferred to @rq on success */
retry:
- rq = __get_request(rl, op, bio, gfp_mask);
+ rq = __get_request(rl, op, bio, flags);
if (!IS_ERR(rq))
return rq;
@@ -1364,7 +1429,7 @@ retry:
return ERR_PTR(-EAGAIN);
}
- if (!gfpflags_allow_blocking(gfp_mask) || unlikely(blk_queue_dying(q))) {
+ if ((flags & BLK_MQ_REQ_NOWAIT) || unlikely(blk_queue_dying(q))) {
blk_put_rl(rl);
return rq;
}
@@ -1391,20 +1456,28 @@ retry:
goto retry;
}
+/* flags: BLK_MQ_REQ_PREEMPT and/or BLK_MQ_REQ_NOWAIT. */
static struct request *blk_old_get_request(struct request_queue *q,
- unsigned int op, gfp_t gfp_mask)
+ unsigned int op, blk_mq_req_flags_t flags)
{
struct request *rq;
+ gfp_t gfp_mask = flags & BLK_MQ_REQ_NOWAIT ? GFP_ATOMIC :
+ __GFP_DIRECT_RECLAIM;
+ int ret = 0;
WARN_ON_ONCE(q->mq_ops);
/* create ioc upfront */
create_io_context(gfp_mask, q->node);
+ ret = blk_queue_enter(q, flags);
+ if (ret)
+ return ERR_PTR(ret);
spin_lock_irq(q->queue_lock);
- rq = get_request(q, op, NULL, gfp_mask);
+ rq = get_request(q, op, NULL, flags);
if (IS_ERR(rq)) {
spin_unlock_irq(q->queue_lock);
+ blk_queue_exit(q);
return rq;
}
@@ -1415,25 +1488,40 @@ static struct request *blk_old_get_request(struct request_queue *q,
return rq;
}
-struct request *blk_get_request(struct request_queue *q, unsigned int op,
- gfp_t gfp_mask)
+/**
+ * blk_get_request_flags - allocate a request
+ * @q: request queue to allocate a request for
+ * @op: operation (REQ_OP_*) and REQ_* flags, e.g. REQ_SYNC.
+ * @flags: BLK_MQ_REQ_* flags, e.g. BLK_MQ_REQ_NOWAIT.
+ */
+struct request *blk_get_request_flags(struct request_queue *q, unsigned int op,
+ blk_mq_req_flags_t flags)
{
struct request *req;
+ WARN_ON_ONCE(op & REQ_NOWAIT);
+ WARN_ON_ONCE(flags & ~(BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_PREEMPT));
+
if (q->mq_ops) {
- req = blk_mq_alloc_request(q, op,
- (gfp_mask & __GFP_DIRECT_RECLAIM) ?
- 0 : BLK_MQ_REQ_NOWAIT);
+ req = blk_mq_alloc_request(q, op, flags);
if (!IS_ERR(req) && q->mq_ops->initialize_rq_fn)
q->mq_ops->initialize_rq_fn(req);
} else {
- req = blk_old_get_request(q, op, gfp_mask);
+ req = blk_old_get_request(q, op, flags);
if (!IS_ERR(req) && q->initialize_rq_fn)
q->initialize_rq_fn(req);
}
return req;
}
+EXPORT_SYMBOL(blk_get_request_flags);
+
+struct request *blk_get_request(struct request_queue *q, unsigned int op,
+ gfp_t gfp_mask)
+{
+ return blk_get_request_flags(q, op, gfp_mask & __GFP_DIRECT_RECLAIM ?
+ 0 : BLK_MQ_REQ_NOWAIT);
+}
EXPORT_SYMBOL(blk_get_request);
/**
@@ -1576,6 +1664,7 @@ void __blk_put_request(struct request_queue *q, struct request *req)
blk_free_request(rl, req);
freed_request(rl, sync, rq_flags);
blk_put_rl(rl);
+ blk_queue_exit(q);
}
}
EXPORT_SYMBOL_GPL(__blk_put_request);
@@ -1857,8 +1946,10 @@ get_rq:
* Grab a free request. This is might sleep but can not fail.
* Returns with the queue unlocked.
*/
- req = get_request(q, bio->bi_opf, bio, GFP_NOIO);
+ blk_queue_enter_live(q);
+ req = get_request(q, bio->bi_opf, bio, 0);
if (IS_ERR(req)) {
+ blk_queue_exit(q);
__wbt_done(q->rq_wb, wb_acct);
if (PTR_ERR(req) == -ENOMEM)
bio->bi_status = BLK_STS_RESOURCE;
@@ -2200,8 +2291,10 @@ blk_qc_t generic_make_request(struct bio *bio)
current->bio_list = bio_list_on_stack;
do {
struct request_queue *q = bio->bi_disk->queue;
+ blk_mq_req_flags_t flags = bio->bi_opf & REQ_NOWAIT ?
+ BLK_MQ_REQ_NOWAIT : 0;
- if (likely(blk_queue_enter(q, bio->bi_opf & REQ_NOWAIT) == 0)) {
+ if (likely(blk_queue_enter(q, flags) == 0)) {
struct bio_list lower, same;
/* Create a fresh bio_list for all subordinate requests */
@@ -2242,6 +2335,40 @@ out:
EXPORT_SYMBOL(generic_make_request);
/**
+ * direct_make_request - hand a buffer directly to its device driver for I/O
+ * @bio: The bio describing the location in memory and on the device.
+ *
+ * This function behaves like generic_make_request(), but does not protect
+ * against recursion. Must only be used if the called driver is known
+ * to not call generic_make_request (or direct_make_request) again from
+ * its make_request function. (Calling direct_make_request again from
+ * a workqueue is perfectly fine as that doesn't recurse).
+ */
+blk_qc_t direct_make_request(struct bio *bio)
+{
+ struct request_queue *q = bio->bi_disk->queue;
+ bool nowait = bio->bi_opf & REQ_NOWAIT;
+ blk_qc_t ret;
+
+ if (!generic_make_request_checks(bio))
+ return BLK_QC_T_NONE;
+
+ if (unlikely(blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0))) {
+ if (nowait && !blk_queue_dying(q))
+ bio->bi_status = BLK_STS_AGAIN;
+ else
+ bio->bi_status = BLK_STS_IOERR;
+ bio_endio(bio);
+ return BLK_QC_T_NONE;
+ }
+
+ ret = q->make_request_fn(q, bio);
+ blk_queue_exit(q);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(direct_make_request);
+
+/**
* submit_bio - submit a bio to the block device layer for I/O
* @bio: The &struct bio which describes the I/O
*
@@ -2285,6 +2412,17 @@ blk_qc_t submit_bio(struct bio *bio)
}
EXPORT_SYMBOL(submit_bio);
+bool blk_poll(struct request_queue *q, blk_qc_t cookie)
+{
+ if (!q->poll_fn || !blk_qc_t_valid(cookie))
+ return false;
+
+ if (current->plug)
+ blk_flush_plug_list(current->plug, false);
+ return q->poll_fn(q, cookie);
+}
+EXPORT_SYMBOL_GPL(blk_poll);
+
/**
* blk_cloned_rq_check_limits - Helper function to check a cloned request
* for new the queue limits
@@ -2350,7 +2488,7 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *
* bypass a potential scheduler on the bottom device for
* insert.
*/
- blk_mq_request_bypass_insert(rq);
+ blk_mq_request_bypass_insert(rq, true);
return BLK_STS_OK;
}
@@ -2464,20 +2602,22 @@ void blk_account_io_done(struct request *req)
* Don't process normal requests when queue is suspended
* or in the process of suspending/resuming
*/
-static struct request *blk_pm_peek_request(struct request_queue *q,
- struct request *rq)
+static bool blk_pm_allow_request(struct request *rq)
{
- if (q->dev && (q->rpm_status == RPM_SUSPENDED ||
- (q->rpm_status != RPM_ACTIVE && !(rq->rq_flags & RQF_PM))))
- return NULL;
- else
- return rq;
+ switch (rq->q->rpm_status) {
+ case RPM_RESUMING:
+ case RPM_SUSPENDING:
+ return rq->rq_flags & RQF_PM;
+ case RPM_SUSPENDED:
+ return false;
+ }
+
+ return true;
}
#else
-static inline struct request *blk_pm_peek_request(struct request_queue *q,
- struct request *rq)
+static bool blk_pm_allow_request(struct request *rq)
{
- return rq;
+ return true;
}
#endif
@@ -2517,6 +2657,48 @@ void blk_account_io_start(struct request *rq, bool new_io)
part_stat_unlock();
}
+static struct request *elv_next_request(struct request_queue *q)
+{
+ struct request *rq;
+ struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL);
+
+ WARN_ON_ONCE(q->mq_ops);
+
+ while (1) {
+ list_for_each_entry(rq, &q->queue_head, queuelist) {
+ if (blk_pm_allow_request(rq))
+ return rq;
+
+ if (rq->rq_flags & RQF_SOFTBARRIER)
+ break;
+ }
+
+ /*
+ * Flush request is running and flush request isn't queueable
+ * in the drive, we can hold the queue till flush request is
+ * finished. Even we don't do this, driver can't dispatch next
+ * requests and will requeue them. And this can improve
+ * throughput too. For example, we have request flush1, write1,
+ * flush 2. flush1 is dispatched, then queue is hold, write1
+ * isn't inserted to queue. After flush1 is finished, flush2
+ * will be dispatched. Since disk cache is already clean,
+ * flush2 will be finished very soon, so looks like flush2 is
+ * folded to flush1.
+ * Since the queue is hold, a flag is set to indicate the queue
+ * should be restarted later. Please see flush_end_io() for
+ * details.
+ */
+ if (fq->flush_pending_idx != fq->flush_running_idx &&
+ !queue_flush_queueable(q)) {
+ fq->flush_queue_delayed = 1;
+ return NULL;
+ }
+ if (unlikely(blk_queue_bypass(q)) ||
+ !q->elevator->type->ops.sq.elevator_dispatch_fn(q, 0))
+ return NULL;
+ }
+}
+
/**
* blk_peek_request - peek at the top of a request queue
* @q: request queue to peek at
@@ -2538,12 +2720,7 @@ struct request *blk_peek_request(struct request_queue *q)
lockdep_assert_held(q->queue_lock);
WARN_ON_ONCE(q->mq_ops);
- while ((rq = __elv_next_request(q)) != NULL) {
-
- rq = blk_pm_peek_request(q, rq);
- if (!rq)
- break;
-
+ while ((rq = elv_next_request(q)) != NULL) {
if (!(rq->rq_flags & RQF_STARTED)) {
/*
* This is the first time the device driver
@@ -2695,6 +2872,27 @@ struct request *blk_fetch_request(struct request_queue *q)
}
EXPORT_SYMBOL(blk_fetch_request);
+/*
+ * Steal bios from a request and add them to a bio list.
+ * The request must not have been partially completed before.
+ */
+void blk_steal_bios(struct bio_list *list, struct request *rq)
+{
+ if (rq->bio) {
+ if (list->tail)
+ list->tail->bi_next = rq->bio;
+ else
+ list->head = rq->bio;
+ list->tail = rq->biotail;
+
+ rq->bio = NULL;
+ rq->biotail = NULL;
+ }
+
+ rq->__data_len = 0;
+}
+EXPORT_SYMBOL_GPL(blk_steal_bios);
+
/**
* blk_update_request - Special helper function for request stacking drivers
* @req: the request being processed
diff --git a/block/blk-flush.c b/block/blk-flush.c
index 4938bec8cfef..f17170675917 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -231,8 +231,13 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error)
/* release the tag's ownership to the req cloned from */
spin_lock_irqsave(&fq->mq_flush_lock, flags);
hctx = blk_mq_map_queue(q, flush_rq->mq_ctx->cpu);
- blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq);
- flush_rq->tag = -1;
+ if (!q->elevator) {
+ blk_mq_tag_set_rq(hctx, flush_rq->tag, fq->orig_rq);
+ flush_rq->tag = -1;
+ } else {
+ blk_mq_put_driver_tag_hctx(hctx, flush_rq);
+ flush_rq->internal_tag = -1;
+ }
}
running = &fq->flush_queue[fq->flush_running_idx];
@@ -318,19 +323,26 @@ static bool blk_kick_flush(struct request_queue *q, struct blk_flush_queue *fq)
blk_rq_init(q, flush_rq);
/*
- * Borrow tag from the first request since they can't
- * be in flight at the same time. And acquire the tag's
- * ownership for flush req.
+ * In case of none scheduler, borrow tag from the first request
+ * since they can't be in flight at the same time. And acquire
+ * the tag's ownership for flush req.
+ *
+ * In case of IO scheduler, flush rq need to borrow scheduler tag
+ * just for cheating put/get driver tag.
*/
if (q->mq_ops) {
struct blk_mq_hw_ctx *hctx;
flush_rq->mq_ctx = first_rq->mq_ctx;
- flush_rq->tag = first_rq->tag;
- fq->orig_rq = first_rq;
- hctx = blk_mq_map_queue(q, first_rq->mq_ctx->cpu);
- blk_mq_tag_set_rq(hctx, first_rq->tag, flush_rq);
+ if (!q->elevator) {
+ fq->orig_rq = first_rq;
+ flush_rq->tag = first_rq->tag;
+ hctx = blk_mq_map_queue(q, first_rq->mq_ctx->cpu);
+ blk_mq_tag_set_rq(hctx, first_rq->tag, flush_rq);
+ } else {
+ flush_rq->internal_tag = first_rq->internal_tag;
+ }
}
flush_rq->cmd_flags = REQ_OP_FLUSH | REQ_PREFLUSH;
@@ -394,6 +406,11 @@ static void mq_flush_data_end_io(struct request *rq, blk_status_t error)
hctx = blk_mq_map_queue(q, ctx->cpu);
+ if (q->elevator) {
+ WARN_ON(rq->tag < 0);
+ blk_mq_put_driver_tag_hctx(hctx, rq);
+ }
+
/*
* After populating an empty queue, kick it to avoid stall. Read
* the comment in flush_end_io().
@@ -463,7 +480,7 @@ void blk_insert_flush(struct request *rq)
if ((policy & REQ_FSEQ_DATA) &&
!(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) {
if (q->mq_ops)
- blk_mq_sched_insert_request(rq, false, true, false, false);
+ blk_mq_request_bypass_insert(rq, false);
else
list_add_tail(&rq->queuelist, &q->queue_head);
return;
diff --git a/block/blk-lib.c b/block/blk-lib.c
index 63fb971d6574..2bc544ce3d2e 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -275,6 +275,40 @@ static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
return min(pages, (sector_t)BIO_MAX_PAGES);
}
+static int __blkdev_issue_zero_pages(struct block_device *bdev,
+ sector_t sector, sector_t nr_sects, gfp_t gfp_mask,
+ struct bio **biop)
+{
+ struct request_queue *q = bdev_get_queue(bdev);
+ struct bio *bio = *biop;
+ int bi_size = 0;
+ unsigned int sz;
+
+ if (!q)
+ return -ENXIO;
+
+ while (nr_sects != 0) {
+ bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
+ gfp_mask);
+ bio->bi_iter.bi_sector = sector;
+ bio_set_dev(bio, bdev);
+ bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
+
+ while (nr_sects != 0) {
+ sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
+ bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
+ nr_sects -= bi_size >> 9;
+ sector += bi_size >> 9;
+ if (bi_size < sz)
+ break;
+ }
+ cond_resched();
+ }
+
+ *biop = bio;
+ return 0;
+}
+
/**
* __blkdev_issue_zeroout - generate number of zero filed write bios
* @bdev: blockdev to issue
@@ -288,12 +322,6 @@ static unsigned int __blkdev_sectors_to_bio_pages(sector_t nr_sects)
* Zero-fill a block range, either using hardware offload or by explicitly
* writing zeroes to the device.
*
- * Note that this function may fail with -EOPNOTSUPP if the driver signals
- * zeroing offload support, but the device fails to process the command (for
- * some devices there is no non-destructive way to verify whether this
- * operation is actually supported). In this case the caller should call
- * retry the call to blkdev_issue_zeroout() and the fallback path will be used.
- *
* If a device is using logical block provisioning, the underlying space will
* not be released if %flags contains BLKDEV_ZERO_NOUNMAP.
*
@@ -305,9 +333,6 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
unsigned flags)
{
int ret;
- int bi_size = 0;
- struct bio *bio = *biop;
- unsigned int sz;
sector_t bs_mask;
bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
@@ -317,30 +342,10 @@ int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects, gfp_mask,
biop, flags);
if (ret != -EOPNOTSUPP || (flags & BLKDEV_ZERO_NOFALLBACK))
- goto out;
-
- ret = 0;
- while (nr_sects != 0) {
- bio = next_bio(bio, __blkdev_sectors_to_bio_pages(nr_sects),
- gfp_mask);
- bio->bi_iter.bi_sector = sector;
- bio_set_dev(bio, bdev);
- bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
-
- while (nr_sects != 0) {
- sz = min((sector_t) PAGE_SIZE, nr_sects << 9);
- bi_size = bio_add_page(bio, ZERO_PAGE(0), sz, 0);
- nr_sects -= bi_size >> 9;
- sector += bi_size >> 9;
- if (bi_size < sz)
- break;
- }
- cond_resched();
- }
+ return ret;
- *biop = bio;
-out:
- return ret;
+ return __blkdev_issue_zero_pages(bdev, sector, nr_sects, gfp_mask,
+ biop);
}
EXPORT_SYMBOL(__blkdev_issue_zeroout);
@@ -360,18 +365,49 @@ EXPORT_SYMBOL(__blkdev_issue_zeroout);
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned flags)
{
- int ret;
- struct bio *bio = NULL;
+ int ret = 0;
+ sector_t bs_mask;
+ struct bio *bio;
struct blk_plug plug;
+ bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
+ bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
+ if ((sector | nr_sects) & bs_mask)
+ return -EINVAL;
+
+retry:
+ bio = NULL;
blk_start_plug(&plug);
- ret = __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask,
- &bio, flags);
+ if (try_write_zeroes) {
+ ret = __blkdev_issue_write_zeroes(bdev, sector, nr_sects,
+ gfp_mask, &bio, flags);
+ } else if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
+ ret = __blkdev_issue_zero_pages(bdev, sector, nr_sects,
+ gfp_mask, &bio);
+ } else {
+ /* No zeroing offload support */
+ ret = -EOPNOTSUPP;
+ }
if (ret == 0 && bio) {
ret = submit_bio_wait(bio);
bio_put(bio);
}
blk_finish_plug(&plug);
+ if (ret && try_write_zeroes) {
+ if (!(flags & BLKDEV_ZERO_NOFALLBACK)) {
+ try_write_zeroes = false;
+ goto retry;
+ }
+ if (!bdev_write_zeroes_sectors(bdev)) {
+ /*
+ * Zeroing offload support was indicated, but the
+ * device reported ILLEGAL REQUEST (for some devices
+ * there is no non-destructive way to verify whether
+ * WRITE ZEROES is actually supported).
+ */
+ ret = -EOPNOTSUPP;
+ }
+ }
return ret;
}
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index de294d775acf..b56a4f35720d 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -54,7 +54,6 @@ static const char *const blk_queue_flag_name[] = {
QUEUE_FLAG_NAME(NOMERGES),
QUEUE_FLAG_NAME(SAME_COMP),
QUEUE_FLAG_NAME(FAIL_IO),
- QUEUE_FLAG_NAME(STACKABLE),
QUEUE_FLAG_NAME(NONROT),
QUEUE_FLAG_NAME(IO_STAT),
QUEUE_FLAG_NAME(DISCARD),
@@ -75,6 +74,7 @@ static const char *const blk_queue_flag_name[] = {
QUEUE_FLAG_NAME(REGISTERED),
QUEUE_FLAG_NAME(SCSI_PASSTHROUGH),
QUEUE_FLAG_NAME(QUIESCED),
+ QUEUE_FLAG_NAME(PREEMPT_ONLY),
};
#undef QUEUE_FLAG_NAME
@@ -180,7 +180,6 @@ static const char *const hctx_state_name[] = {
HCTX_STATE_NAME(STOPPED),
HCTX_STATE_NAME(TAG_ACTIVE),
HCTX_STATE_NAME(SCHED_RESTART),
- HCTX_STATE_NAME(TAG_WAITING),
HCTX_STATE_NAME(START_ON_RUN),
};
#undef HCTX_STATE_NAME
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 4ab69435708c..c117bd8fd1f6 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -81,20 +81,103 @@ static bool blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx)
} else
clear_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
- if (blk_mq_hctx_has_pending(hctx)) {
- blk_mq_run_hw_queue(hctx, true);
- return true;
- }
+ return blk_mq_run_hw_queue(hctx, true);
+}
- return false;
+/*
+ * Only SCSI implements .get_budget and .put_budget, and SCSI restarts
+ * its queue by itself in its completion handler, so we don't need to
+ * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE.
+ */
+static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx)
+{
+ struct request_queue *q = hctx->queue;
+ struct elevator_queue *e = q->elevator;
+ LIST_HEAD(rq_list);
+
+ do {
+ struct request *rq;
+
+ if (e->type->ops.mq.has_work &&
+ !e->type->ops.mq.has_work(hctx))
+ break;
+
+ if (!blk_mq_get_dispatch_budget(hctx))
+ break;
+
+ rq = e->type->ops.mq.dispatch_request(hctx);
+ if (!rq) {
+ blk_mq_put_dispatch_budget(hctx);
+ break;
+ }
+
+ /*
+ * Now this rq owns the budget which has to be released
+ * if this rq won't be queued to driver via .queue_rq()
+ * in blk_mq_dispatch_rq_list().
+ */
+ list_add(&rq->queuelist, &rq_list);
+ } while (blk_mq_dispatch_rq_list(q, &rq_list, true));
}
+static struct blk_mq_ctx *blk_mq_next_ctx(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *ctx)
+{
+ unsigned idx = ctx->index_hw;
+
+ if (++idx == hctx->nr_ctx)
+ idx = 0;
+
+ return hctx->ctxs[idx];
+}
+
+/*
+ * Only SCSI implements .get_budget and .put_budget, and SCSI restarts
+ * its queue by itself in its completion handler, so we don't need to
+ * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE.
+ */
+static void blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx)
+{
+ struct request_queue *q = hctx->queue;
+ LIST_HEAD(rq_list);
+ struct blk_mq_ctx *ctx = READ_ONCE(hctx->dispatch_from);
+
+ do {
+ struct request *rq;
+
+ if (!sbitmap_any_bit_set(&hctx->ctx_map))
+ break;
+
+ if (!blk_mq_get_dispatch_budget(hctx))
+ break;
+
+ rq = blk_mq_dequeue_from_ctx(hctx, ctx);
+ if (!rq) {
+ blk_mq_put_dispatch_budget(hctx);
+ break;
+ }
+
+ /*
+ * Now this rq owns the budget which has to be released
+ * if this rq won't be queued to driver via .queue_rq()
+ * in blk_mq_dispatch_rq_list().
+ */
+ list_add(&rq->queuelist, &rq_list);
+
+ /* round robin for fair dispatch */
+ ctx = blk_mq_next_ctx(hctx, rq->mq_ctx);
+
+ } while (blk_mq_dispatch_rq_list(q, &rq_list, true));
+
+ WRITE_ONCE(hctx->dispatch_from, ctx);
+}
+
+/* return true if hw queue need to be run again */
void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)
{
struct request_queue *q = hctx->queue;
struct elevator_queue *e = q->elevator;
const bool has_sched_dispatch = e && e->type->ops.mq.dispatch_request;
- bool did_work = false;
LIST_HEAD(rq_list);
/* RCU or SRCU read lock is needed before checking quiesced flag */
@@ -122,29 +205,34 @@ void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)
* scheduler, we can no longer merge or sort them. So it's best to
* leave them there for as long as we can. Mark the hw queue as
* needing a restart in that case.
+ *
+ * We want to dispatch from the scheduler if there was nothing
+ * on the dispatch list or we were able to dispatch from the
+ * dispatch list.
*/
if (!list_empty(&rq_list)) {
blk_mq_sched_mark_restart_hctx(hctx);
- did_work = blk_mq_dispatch_rq_list(q, &rq_list);
- } else if (!has_sched_dispatch) {
+ if (blk_mq_dispatch_rq_list(q, &rq_list, false)) {
+ if (has_sched_dispatch)
+ blk_mq_do_dispatch_sched(hctx);
+ else
+ blk_mq_do_dispatch_ctx(hctx);
+ }
+ } else if (has_sched_dispatch) {
+ blk_mq_do_dispatch_sched(hctx);
+ } else if (q->mq_ops->get_budget) {
+ /*
+ * If we need to get budget before queuing request, we
+ * dequeue request one by one from sw queue for avoiding
+ * to mess up I/O merge when dispatch runs out of resource.
+ *
+ * TODO: get more budgets, and dequeue more requests in
+ * one time.
+ */
+ blk_mq_do_dispatch_ctx(hctx);
+ } else {
blk_mq_flush_busy_ctxs(hctx, &rq_list);
- blk_mq_dispatch_rq_list(q, &rq_list);
- }
-
- /*
- * We want to dispatch from the scheduler if we had no work left
- * on the dispatch list, OR if we did have work but weren't able
- * to make progress.
- */
- if (!did_work && has_sched_dispatch) {
- do {
- struct request *rq;
-
- rq = e->type->ops.mq.dispatch_request(hctx);
- if (!rq)
- break;
- list_add(&rq->queuelist, &rq_list);
- } while (blk_mq_dispatch_rq_list(q, &rq_list));
+ blk_mq_dispatch_rq_list(q, &rq_list, false);
}
}
@@ -260,21 +348,21 @@ void blk_mq_sched_request_inserted(struct request *rq)
EXPORT_SYMBOL_GPL(blk_mq_sched_request_inserted);
static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx,
+ bool has_sched,
struct request *rq)
{
- if (rq->tag == -1) {
- rq->rq_flags |= RQF_SORTED;
- return false;
+ /* dispatch flush rq directly */
+ if (rq->rq_flags & RQF_FLUSH_SEQ) {
+ spin_lock(&hctx->lock);
+ list_add(&rq->queuelist, &hctx->dispatch);
+ spin_unlock(&hctx->lock);
+ return true;
}
- /*
- * If we already have a real request tag, send directly to
- * the dispatch list.
- */
- spin_lock(&hctx->lock);
- list_add(&rq->queuelist, &hctx->dispatch);
- spin_unlock(&hctx->lock);
- return true;
+ if (has_sched)
+ rq->rq_flags |= RQF_SORTED;
+
+ return false;
}
/**
@@ -339,21 +427,6 @@ done:
}
}
-/*
- * Add flush/fua to the queue. If we fail getting a driver tag, then
- * punt to the requeue list. Requeue will re-invoke us from a context
- * that's safe to block from.
- */
-static void blk_mq_sched_insert_flush(struct blk_mq_hw_ctx *hctx,
- struct request *rq, bool can_block)
-{
- if (blk_mq_get_driver_tag(rq, &hctx, can_block)) {
- blk_insert_flush(rq);
- blk_mq_run_hw_queue(hctx, true);
- } else
- blk_mq_add_to_requeue_list(rq, false, true);
-}
-
void blk_mq_sched_insert_request(struct request *rq, bool at_head,
bool run_queue, bool async, bool can_block)
{
@@ -362,12 +435,15 @@ void blk_mq_sched_insert_request(struct request *rq, bool at_head,
struct blk_mq_ctx *ctx = rq->mq_ctx;
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
- if (rq->tag == -1 && op_is_flush(rq->cmd_flags)) {
- blk_mq_sched_insert_flush(hctx, rq, can_block);
- return;
+ /* flush rq in flush machinery need to be dispatched directly */
+ if (!(rq->rq_flags & RQF_FLUSH_SEQ) && op_is_flush(rq->cmd_flags)) {
+ blk_insert_flush(rq);
+ goto run;
}
- if (e && blk_mq_sched_bypass_insert(hctx, rq))
+ WARN_ON(e && (rq->tag != -1));
+
+ if (blk_mq_sched_bypass_insert(hctx, !!e, rq))
goto run;
if (e && e->type->ops.mq.insert_requests) {
@@ -393,23 +469,6 @@ void blk_mq_sched_insert_requests(struct request_queue *q,
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
struct elevator_queue *e = hctx->queue->elevator;
- if (e) {
- struct request *rq, *next;
-
- /*
- * We bypass requests that already have a driver tag assigned,
- * which should only be flushes. Flushes are only ever inserted
- * as single requests, so we shouldn't ever hit the
- * WARN_ON_ONCE() below (but let's handle it just in case).
- */
- list_for_each_entry_safe(rq, next, list, queuelist) {
- if (WARN_ON_ONCE(rq->tag != -1)) {
- list_del_init(&rq->queuelist);
- blk_mq_sched_bypass_insert(hctx, rq);
- }
- }
- }
-
if (e && e->type->ops.mq.insert_requests)
e->type->ops.mq.insert_requests(hctx, list, false);
else
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 6714507aa6c7..c81b40ecd3f1 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -298,12 +298,12 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset,
}
EXPORT_SYMBOL(blk_mq_tagset_busy_iter);
-int blk_mq_reinit_tagset(struct blk_mq_tag_set *set,
- int (reinit_request)(void *, struct request *))
+int blk_mq_tagset_iter(struct blk_mq_tag_set *set, void *data,
+ int (fn)(void *, struct request *))
{
int i, j, ret = 0;
- if (WARN_ON_ONCE(!reinit_request))
+ if (WARN_ON_ONCE(!fn))
goto out;
for (i = 0; i < set->nr_hw_queues; i++) {
@@ -316,8 +316,7 @@ int blk_mq_reinit_tagset(struct blk_mq_tag_set *set,
if (!tags->static_rqs[j])
continue;
- ret = reinit_request(set->driver_data,
- tags->static_rqs[j]);
+ ret = fn(data, tags->static_rqs[j]);
if (ret)
goto out;
}
@@ -326,7 +325,7 @@ int blk_mq_reinit_tagset(struct blk_mq_tag_set *set,
out:
return ret;
}
-EXPORT_SYMBOL_GPL(blk_mq_reinit_tagset);
+EXPORT_SYMBOL_GPL(blk_mq_tagset_iter);
void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
void *priv)
diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h
index c190165d92ea..61deab0b5a5a 100644
--- a/block/blk-mq-tag.h
+++ b/block/blk-mq-tag.h
@@ -45,13 +45,8 @@ static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
}
enum {
- BLK_MQ_TAG_CACHE_MIN = 1,
- BLK_MQ_TAG_CACHE_MAX = 64,
-};
-
-enum {
BLK_MQ_TAG_FAIL = -1U,
- BLK_MQ_TAG_MIN = BLK_MQ_TAG_CACHE_MIN,
+ BLK_MQ_TAG_MIN = 1,
BLK_MQ_TAG_MAX = BLK_MQ_TAG_FAIL - 1,
};
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 98a18609755e..b600463791ec 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -37,6 +37,7 @@
#include "blk-wbt.h"
#include "blk-mq-sched.h"
+static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie);
static void blk_mq_poll_stats_start(struct request_queue *q);
static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb);
@@ -60,10 +61,10 @@ static int blk_mq_poll_stats_bkt(const struct request *rq)
/*
* Check if any of the ctx's have pending work in this hardware queue
*/
-bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx)
+static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx)
{
- return sbitmap_any_bit_set(&hctx->ctx_map) ||
- !list_empty_careful(&hctx->dispatch) ||
+ return !list_empty_careful(&hctx->dispatch) ||
+ sbitmap_any_bit_set(&hctx->ctx_map) ||
blk_mq_sched_has_work(hctx);
}
@@ -125,7 +126,8 @@ void blk_freeze_queue_start(struct request_queue *q)
freeze_depth = atomic_inc_return(&q->mq_freeze_depth);
if (freeze_depth == 1) {
percpu_ref_kill(&q->q_usage_counter);
- blk_mq_run_hw_queues(q, false);
+ if (q->mq_ops)
+ blk_mq_run_hw_queues(q, false);
}
}
EXPORT_SYMBOL_GPL(blk_freeze_queue_start);
@@ -255,13 +257,6 @@ void blk_mq_wake_waiters(struct request_queue *q)
queue_for_each_hw_ctx(q, hctx, i)
if (blk_mq_hw_queue_mapped(hctx))
blk_mq_tag_wakeup_all(hctx->tags, true);
-
- /*
- * If we are called because the queue has now been marked as
- * dying, we need to ensure that processes currently waiting on
- * the queue are notified as well.
- */
- wake_up_all(&q->mq_freeze_wq);
}
bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx)
@@ -296,6 +291,8 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
rq->q = data->q;
rq->mq_ctx = data->ctx;
rq->cmd_flags = op;
+ if (data->flags & BLK_MQ_REQ_PREEMPT)
+ rq->rq_flags |= RQF_PREEMPT;
if (blk_queue_io_stat(data->q))
rq->rq_flags |= RQF_IO_STAT;
/* do not touch atomic flags, it needs atomic ops against the timer */
@@ -336,12 +333,14 @@ static struct request *blk_mq_get_request(struct request_queue *q,
struct elevator_queue *e = q->elevator;
struct request *rq;
unsigned int tag;
- struct blk_mq_ctx *local_ctx = NULL;
+ bool put_ctx_on_error = false;
blk_queue_enter_live(q);
data->q = q;
- if (likely(!data->ctx))
- data->ctx = local_ctx = blk_mq_get_ctx(q);
+ if (likely(!data->ctx)) {
+ data->ctx = blk_mq_get_ctx(q);
+ put_ctx_on_error = true;
+ }
if (likely(!data->hctx))
data->hctx = blk_mq_map_queue(q, data->ctx->cpu);
if (op & REQ_NOWAIT)
@@ -360,8 +359,8 @@ static struct request *blk_mq_get_request(struct request_queue *q,
tag = blk_mq_get_tag(data);
if (tag == BLK_MQ_TAG_FAIL) {
- if (local_ctx) {
- blk_mq_put_ctx(local_ctx);
+ if (put_ctx_on_error) {
+ blk_mq_put_ctx(data->ctx);
data->ctx = NULL;
}
blk_queue_exit(q);
@@ -384,13 +383,13 @@ static struct request *blk_mq_get_request(struct request_queue *q,
}
struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
- unsigned int flags)
+ blk_mq_req_flags_t flags)
{
struct blk_mq_alloc_data alloc_data = { .flags = flags };
struct request *rq;
int ret;
- ret = blk_queue_enter(q, flags & BLK_MQ_REQ_NOWAIT);
+ ret = blk_queue_enter(q, flags);
if (ret)
return ERR_PTR(ret);
@@ -410,7 +409,7 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
EXPORT_SYMBOL(blk_mq_alloc_request);
struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
- unsigned int op, unsigned int flags, unsigned int hctx_idx)
+ unsigned int op, blk_mq_req_flags_t flags, unsigned int hctx_idx)
{
struct blk_mq_alloc_data alloc_data = { .flags = flags };
struct request *rq;
@@ -429,7 +428,7 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
if (hctx_idx >= q->nr_hw_queues)
return ERR_PTR(-EIO);
- ret = blk_queue_enter(q, true);
+ ret = blk_queue_enter(q, flags);
if (ret)
return ERR_PTR(ret);
@@ -476,8 +475,14 @@ void blk_mq_free_request(struct request *rq)
if (rq->rq_flags & RQF_MQ_INFLIGHT)
atomic_dec(&hctx->nr_active);
+ if (unlikely(laptop_mode && !blk_rq_is_passthrough(rq)))
+ laptop_io_completion(q->backing_dev_info);
+
wbt_done(q->rq_wb, &rq->issue_stat);
+ if (blk_rq_rl(rq))
+ blk_put_rl(blk_rq_rl(rq));
+
clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
clear_bit(REQ_ATOM_POLL_SLEPT, &rq->atomic_flags);
if (rq->tag != -1)
@@ -593,22 +598,32 @@ void blk_mq_start_request(struct request *rq)
blk_add_timer(rq);
- /*
- * Ensure that ->deadline is visible before set the started
- * flag and clear the completed flag.
- */
- smp_mb__before_atomic();
+ WARN_ON_ONCE(test_bit(REQ_ATOM_STARTED, &rq->atomic_flags));
/*
* 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
* the request, otherwise we'll ignore the completion event.
+ *
+ * Ensure that ->deadline is visible before we set STARTED, such that
+ * blk_mq_check_expired() is guaranteed to observe our ->deadline when
+ * it observes STARTED.
*/
- if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
- set_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
- if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags))
+ smp_wmb();
+ set_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
+ if (test_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags)) {
+ /*
+ * Coherence order guarantees these consecutive stores to a
+ * single variable propagate in the specified order. Thus the
+ * clear_bit() is ordered _after_ the set bit. See
+ * blk_mq_check_expired().
+ *
+ * (the bits must be part of the same byte for this to be
+ * true).
+ */
clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
+ }
if (q->dma_drain_size && blk_rq_bytes(rq)) {
/*
@@ -634,6 +649,8 @@ static void __blk_mq_requeue_request(struct request *rq)
{
struct request_queue *q = rq->q;
+ blk_mq_put_driver_tag(rq);
+
trace_block_rq_requeue(q, rq);
wbt_requeue(q->rq_wb, &rq->issue_stat);
blk_mq_sched_requeue_request(rq);
@@ -690,7 +707,7 @@ void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
/*
* We abuse this flag that is otherwise used by the I/O scheduler to
- * request head insertation from the workqueue.
+ * request head insertion from the workqueue.
*/
BUG_ON(rq->rq_flags & RQF_SOFTBARRIER);
@@ -778,11 +795,20 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
struct request *rq, void *priv, bool reserved)
{
struct blk_mq_timeout_data *data = priv;
+ unsigned long deadline;
if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
return;
/*
+ * Ensures that if we see STARTED we must also see our
+ * up-to-date deadline, see blk_mq_start_request().
+ */
+ smp_rmb();
+
+ deadline = READ_ONCE(rq->deadline);
+
+ /*
* The rq being checked may have been freed and reallocated
* out already here, we avoid this race by checking rq->deadline
* and REQ_ATOM_COMPLETE flag together:
@@ -795,11 +821,20 @@ static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
* and clearing the flag in blk_mq_start_request(), so
* this rq won't be timed out too.
*/
- if (time_after_eq(jiffies, rq->deadline)) {
- if (!blk_mark_rq_complete(rq))
+ if (time_after_eq(jiffies, deadline)) {
+ if (!blk_mark_rq_complete(rq)) {
+ /*
+ * Again coherence order ensures that consecutive reads
+ * from the same variable must be in that order. This
+ * ensures that if we see COMPLETE clear, we must then
+ * see STARTED set and we'll ignore this timeout.
+ *
+ * (There's also the MB implied by the test_and_clear())
+ */
blk_mq_rq_timed_out(rq, reserved);
- } else if (!data->next_set || time_after(data->next, rq->deadline)) {
- data->next = rq->deadline;
+ }
+ } else if (!data->next_set || time_after(data->next, deadline)) {
+ data->next = deadline;
data->next_set = 1;
}
}
@@ -880,6 +915,45 @@ void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list)
}
EXPORT_SYMBOL_GPL(blk_mq_flush_busy_ctxs);
+struct dispatch_rq_data {
+ struct blk_mq_hw_ctx *hctx;
+ struct request *rq;
+};
+
+static bool dispatch_rq_from_ctx(struct sbitmap *sb, unsigned int bitnr,
+ void *data)
+{
+ struct dispatch_rq_data *dispatch_data = data;
+ struct blk_mq_hw_ctx *hctx = dispatch_data->hctx;
+ struct blk_mq_ctx *ctx = hctx->ctxs[bitnr];
+
+ spin_lock(&ctx->lock);
+ if (unlikely(!list_empty(&ctx->rq_list))) {
+ dispatch_data->rq = list_entry_rq(ctx->rq_list.next);
+ list_del_init(&dispatch_data->rq->queuelist);
+ if (list_empty(&ctx->rq_list))
+ sbitmap_clear_bit(sb, bitnr);
+ }
+ spin_unlock(&ctx->lock);
+
+ return !dispatch_data->rq;
+}
+
+struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *start)
+{
+ unsigned off = start ? start->index_hw : 0;
+ struct dispatch_rq_data data = {
+ .hctx = hctx,
+ .rq = NULL,
+ };
+
+ __sbitmap_for_each_set(&hctx->ctx_map, off,
+ dispatch_rq_from_ctx, &data);
+
+ return data.rq;
+}
+
static inline unsigned int queued_to_index(unsigned int queued)
{
if (!queued)
@@ -920,109 +994,95 @@ done:
return rq->tag != -1;
}
-static void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
- struct request *rq)
-{
- blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
- rq->tag = -1;
-
- if (rq->rq_flags & RQF_MQ_INFLIGHT) {
- rq->rq_flags &= ~RQF_MQ_INFLIGHT;
- atomic_dec(&hctx->nr_active);
- }
-}
-
-static void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
- struct request *rq)
-{
- if (rq->tag == -1 || rq->internal_tag == -1)
- return;
-
- __blk_mq_put_driver_tag(hctx, rq);
-}
-
-static void blk_mq_put_driver_tag(struct request *rq)
+static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode,
+ int flags, void *key)
{
struct blk_mq_hw_ctx *hctx;
- if (rq->tag == -1 || rq->internal_tag == -1)
- return;
+ hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait);
- hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
- __blk_mq_put_driver_tag(hctx, rq);
+ list_del_init(&wait->entry);
+ blk_mq_run_hw_queue(hctx, true);
+ return 1;
}
/*
- * If we fail getting a driver tag because all the driver tags are already
- * assigned and on the dispatch list, BUT the first entry does not have a
- * tag, then we could deadlock. For that case, move entries with assigned
- * driver tags to the front, leaving the set of tagged requests in the
- * same order, and the untagged set in the same order.
+ * Mark us waiting for a tag. For shared tags, this involves hooking us into
+ * the tag wakeups. For non-shared tags, we can simply mark us nedeing a
+ * restart. For both caes, take care to check the condition again after
+ * marking us as waiting.
*/
-static bool reorder_tags_to_front(struct list_head *list)
-{
- struct request *rq, *tmp, *first = NULL;
-
- list_for_each_entry_safe_reverse(rq, tmp, list, queuelist) {
- if (rq == first)
- break;
- if (rq->tag != -1) {
- list_move(&rq->queuelist, list);
- if (!first)
- first = rq;
- }
- }
-
- return first != NULL;
-}
-
-static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, int flags,
- void *key)
+static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx **hctx,
+ struct request *rq)
{
- struct blk_mq_hw_ctx *hctx;
+ struct blk_mq_hw_ctx *this_hctx = *hctx;
+ bool shared_tags = (this_hctx->flags & BLK_MQ_F_TAG_SHARED) != 0;
+ struct sbq_wait_state *ws;
+ wait_queue_entry_t *wait;
+ bool ret;
- hctx = container_of(wait, struct blk_mq_hw_ctx, dispatch_wait);
+ if (!shared_tags) {
+ if (!test_bit(BLK_MQ_S_SCHED_RESTART, &this_hctx->state))
+ set_bit(BLK_MQ_S_SCHED_RESTART, &this_hctx->state);
+ } else {
+ wait = &this_hctx->dispatch_wait;
+ if (!list_empty_careful(&wait->entry))
+ return false;
- list_del(&wait->entry);
- clear_bit_unlock(BLK_MQ_S_TAG_WAITING, &hctx->state);
- blk_mq_run_hw_queue(hctx, true);
- return 1;
-}
+ spin_lock(&this_hctx->lock);
+ if (!list_empty(&wait->entry)) {
+ spin_unlock(&this_hctx->lock);
+ return false;
+ }
-static bool blk_mq_dispatch_wait_add(struct blk_mq_hw_ctx *hctx)
-{
- struct sbq_wait_state *ws;
+ ws = bt_wait_ptr(&this_hctx->tags->bitmap_tags, this_hctx);
+ add_wait_queue(&ws->wait, wait);
+ }
/*
- * The TAG_WAITING bit serves as a lock protecting hctx->dispatch_wait.
- * The thread which wins the race to grab this bit adds the hardware
- * queue to the wait queue.
+ * It's possible that a tag was freed in the window between the
+ * allocation failure and adding the hardware queue to the wait
+ * queue.
*/
- if (test_bit(BLK_MQ_S_TAG_WAITING, &hctx->state) ||
- test_and_set_bit_lock(BLK_MQ_S_TAG_WAITING, &hctx->state))
- return false;
+ ret = blk_mq_get_driver_tag(rq, hctx, false);
- init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake);
- ws = bt_wait_ptr(&hctx->tags->bitmap_tags, hctx);
+ if (!shared_tags) {
+ /*
+ * Don't clear RESTART here, someone else could have set it.
+ * At most this will cost an extra queue run.
+ */
+ return ret;
+ } else {
+ if (!ret) {
+ spin_unlock(&this_hctx->lock);
+ return false;
+ }
- /*
- * As soon as this returns, it's no longer safe to fiddle with
- * hctx->dispatch_wait, since a completion can wake up the wait queue
- * and unlock the bit.
- */
- add_wait_queue(&ws->wait, &hctx->dispatch_wait);
- return true;
+ /*
+ * We got a tag, remove ourselves from the wait queue to ensure
+ * someone else gets the wakeup.
+ */
+ spin_lock_irq(&ws->wait.lock);
+ list_del_init(&wait->entry);
+ spin_unlock_irq(&ws->wait.lock);
+ spin_unlock(&this_hctx->lock);
+ return true;
+ }
}
-bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
+bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
+ bool got_budget)
{
struct blk_mq_hw_ctx *hctx;
- struct request *rq;
+ struct request *rq, *nxt;
+ bool no_tag = false;
int errors, queued;
if (list_empty(list))
return false;
+ WARN_ON(!list_is_singular(list) && got_budget);
+
/*
* Now process all the entries, sending them to the driver.
*/
@@ -1033,23 +1093,29 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
rq = list_first_entry(list, struct request, queuelist);
if (!blk_mq_get_driver_tag(rq, &hctx, false)) {
- if (!queued && reorder_tags_to_front(list))
- continue;
-
/*
* The initial allocation attempt failed, so we need to
- * rerun the hardware queue when a tag is freed.
+ * rerun the hardware queue when a tag is freed. The
+ * waitqueue takes care of that. If the queue is run
+ * before we add this entry back on the dispatch list,
+ * we'll re-run it below.
*/
- if (!blk_mq_dispatch_wait_add(hctx))
+ if (!blk_mq_mark_tag_wait(&hctx, rq)) {
+ if (got_budget)
+ blk_mq_put_dispatch_budget(hctx);
+ /*
+ * For non-shared tags, the RESTART check
+ * will suffice.
+ */
+ if (hctx->flags & BLK_MQ_F_TAG_SHARED)
+ no_tag = true;
break;
+ }
+ }
- /*
- * It's possible that a tag was freed in the window
- * between the allocation failure and adding the
- * hardware queue to the wait queue.
- */
- if (!blk_mq_get_driver_tag(rq, &hctx, false))
- break;
+ if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) {
+ blk_mq_put_driver_tag(rq);
+ break;
}
list_del_init(&rq->queuelist);
@@ -1063,15 +1129,21 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
if (list_empty(list))
bd.last = true;
else {
- struct request *nxt;
-
nxt = list_first_entry(list, struct request, queuelist);
bd.last = !blk_mq_get_driver_tag(nxt, NULL, false);
}
ret = q->mq_ops->queue_rq(hctx, &bd);
if (ret == BLK_STS_RESOURCE) {
- blk_mq_put_driver_tag_hctx(hctx, rq);
+ /*
+ * If an I/O scheduler has been configured and we got a
+ * driver tag for the next request already, free it
+ * again.
+ */
+ if (!list_empty(list)) {
+ nxt = list_first_entry(list, struct request, queuelist);
+ blk_mq_put_driver_tag(nxt);
+ }
list_add(&rq->queuelist, list);
__blk_mq_requeue_request(rq);
break;
@@ -1093,13 +1165,6 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
* that is where we will continue on next queue run.
*/
if (!list_empty(list)) {
- /*
- * If an I/O scheduler has been configured and we got a driver
- * tag for the next request already, free it again.
- */
- rq = list_first_entry(list, struct request, queuelist);
- blk_mq_put_driver_tag(rq);
-
spin_lock(&hctx->lock);
list_splice_init(list, &hctx->dispatch);
spin_unlock(&hctx->lock);
@@ -1109,10 +1174,10 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
* it is no longer set that means that it was cleared by another
* thread and hence that a queue rerun is needed.
*
- * If TAG_WAITING is set that means that an I/O scheduler has
- * been configured and another thread is waiting for a driver
- * tag. To guarantee fairness, do not rerun this hardware queue
- * but let the other thread grab the driver tag.
+ * If 'no_tag' is set, that means that we failed getting
+ * a driver tag with an I/O scheduler attached. If our dispatch
+ * waitqueue is no longer active, ensure that we run the queue
+ * AFTER adding our entries back to the list.
*
* If no I/O scheduler has been configured it is possible that
* the hardware queue got stopped and restarted before requests
@@ -1124,8 +1189,8 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list)
* returning BLK_STS_RESOURCE. Two exceptions are scsi-mq
* and dm-rq.
*/
- if (!blk_mq_sched_needs_restart(hctx) &&
- !test_bit(BLK_MQ_S_TAG_WAITING, &hctx->state))
+ if (!blk_mq_sched_needs_restart(hctx) ||
+ (no_tag && list_empty_careful(&hctx->dispatch_wait.entry)))
blk_mq_run_hw_queue(hctx, true);
}
@@ -1218,9 +1283,14 @@ void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs)
}
EXPORT_SYMBOL(blk_mq_delay_run_hw_queue);
-void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
+bool blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
{
- __blk_mq_delay_run_hw_queue(hctx, async, 0);
+ if (blk_mq_hctx_has_pending(hctx)) {
+ __blk_mq_delay_run_hw_queue(hctx, async, 0);
+ return true;
+ }
+
+ return false;
}
EXPORT_SYMBOL(blk_mq_run_hw_queue);
@@ -1230,8 +1300,7 @@ void blk_mq_run_hw_queues(struct request_queue *q, bool async)
int i;
queue_for_each_hw_ctx(q, hctx, i) {
- if (!blk_mq_hctx_has_pending(hctx) ||
- blk_mq_hctx_stopped(hctx))
+ if (blk_mq_hctx_stopped(hctx))
continue;
blk_mq_run_hw_queue(hctx, async);
@@ -1405,7 +1474,7 @@ void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
* Should only be used carefully, when the caller knows we want to
* bypass a potential IO scheduler on the target device.
*/
-void blk_mq_request_bypass_insert(struct request *rq)
+void blk_mq_request_bypass_insert(struct request *rq, bool run_queue)
{
struct blk_mq_ctx *ctx = rq->mq_ctx;
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(rq->q, ctx->cpu);
@@ -1414,7 +1483,8 @@ void blk_mq_request_bypass_insert(struct request *rq)
list_add_tail(&rq->queuelist, &hctx->dispatch);
spin_unlock(&hctx->lock);
- blk_mq_run_hw_queue(hctx, false);
+ if (run_queue)
+ blk_mq_run_hw_queue(hctx, false);
}
void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
@@ -1501,13 +1571,9 @@ static void blk_mq_bio_to_request(struct request *rq, struct bio *bio)
{
blk_init_request_from_bio(rq, bio);
- blk_account_io_start(rq, true);
-}
+ blk_rq_set_rl(rq, blk_get_rl(rq->q, bio));
-static inline bool hctx_allow_merges(struct blk_mq_hw_ctx *hctx)
-{
- return (hctx->flags & BLK_MQ_F_SHOULD_MERGE) &&
- !blk_queue_nomerges(hctx->queue);
+ blk_account_io_start(rq, true);
}
static inline void blk_mq_queue_io(struct blk_mq_hw_ctx *hctx,
@@ -1552,6 +1618,11 @@ static void __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
if (!blk_mq_get_driver_tag(rq, NULL, false))
goto insert;
+ if (!blk_mq_get_dispatch_budget(hctx)) {
+ blk_mq_put_driver_tag(rq);
+ goto insert;
+ }
+
new_cookie = request_to_qc_t(hctx, rq);
/*
@@ -1641,13 +1712,10 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
if (unlikely(is_flush_fua)) {
blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio);
- if (q->elevator) {
- blk_mq_sched_insert_request(rq, false, true, true,
- true);
- } else {
- blk_insert_flush(rq);
- blk_mq_run_hw_queue(data.hctx, true);
- }
+
+ /* bypass scheduler for flush rq */
+ blk_insert_flush(rq);
+ blk_mq_run_hw_queue(data.hctx, true);
} else if (plug && q->nr_hw_queues == 1) {
struct request *last = NULL;
@@ -1990,6 +2058,9 @@ static int blk_mq_init_hctx(struct request_queue *q,
hctx->nr_ctx = 0;
+ init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake);
+ INIT_LIST_HEAD(&hctx->dispatch_wait.entry);
+
if (set->ops->init_hctx &&
set->ops->init_hctx(hctx, set->driver_data, hctx_idx))
goto free_bitmap;
@@ -2229,8 +2300,11 @@ static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set,
mutex_lock(&set->tag_list_lock);
- /* Check to see if we're transitioning to shared (from 1 to 2 queues). */
- if (!list_empty(&set->tag_list) && !(set->flags & BLK_MQ_F_TAG_SHARED)) {
+ /*
+ * Check to see if we're transitioning to shared (from 1 to 2 queues).
+ */
+ if (!list_empty(&set->tag_list) &&
+ !(set->flags & BLK_MQ_F_TAG_SHARED)) {
set->flags |= BLK_MQ_F_TAG_SHARED;
/* update existing queue */
blk_mq_update_tag_set_depth(set, true);
@@ -2404,6 +2478,8 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
spin_lock_init(&q->requeue_lock);
blk_queue_make_request(q, blk_mq_make_request);
+ if (q->mq_ops->poll)
+ q->poll_fn = blk_mq_poll;
/*
* Do this after blk_queue_make_request() overrides it...
@@ -2460,10 +2536,9 @@ static void blk_mq_queue_reinit(struct request_queue *q)
/*
* redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe
- * we should change hctx numa_node according to new topology (this
- * involves free and re-allocate memory, worthy doing?)
+ * we should change hctx numa_node according to the new topology (this
+ * involves freeing and re-allocating memory, worth doing?)
*/
-
blk_mq_map_swqueue(q);
blk_mq_sysfs_register(q);
@@ -2552,6 +2627,9 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
if (!set->ops->queue_rq)
return -EINVAL;
+ if (!set->ops->get_budget ^ !set->ops->put_budget)
+ return -EINVAL;
+
if (set->queue_depth > BLK_MQ_MAX_DEPTH) {
pr_info("blk-mq: reduced tag depth to %u\n",
BLK_MQ_MAX_DEPTH);
@@ -2642,8 +2720,7 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
* queue depth. This is similar to what the old code would do.
*/
if (!hctx->sched_tags) {
- ret = blk_mq_tag_update_depth(hctx, &hctx->tags,
- min(nr, set->queue_depth),
+ ret = blk_mq_tag_update_depth(hctx, &hctx->tags, nr,
false);
} else {
ret = blk_mq_tag_update_depth(hctx, &hctx->sched_tags,
@@ -2863,20 +2940,14 @@ static bool __blk_mq_poll(struct blk_mq_hw_ctx *hctx, struct request *rq)
return false;
}
-bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie)
+static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie)
{
struct blk_mq_hw_ctx *hctx;
- struct blk_plug *plug;
struct request *rq;
- if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) ||
- !test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
+ if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
return false;
- plug = current->plug;
- if (plug)
- blk_flush_plug_list(plug, false);
-
hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)];
if (!blk_qc_t_is_internal(cookie))
rq = blk_mq_tag_to_rq(hctx->tags, blk_qc_t_to_tag(cookie));
@@ -2894,10 +2965,15 @@ bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie)
return __blk_mq_poll(hctx, rq);
}
-EXPORT_SYMBOL_GPL(blk_mq_poll);
static int __init blk_mq_init(void)
{
+ /*
+ * See comment in block/blk.h rq_atomic_flags enum
+ */
+ BUILD_BUG_ON((REQ_ATOM_STARTED / BITS_PER_BYTE) !=
+ (REQ_ATOM_COMPLETE / BITS_PER_BYTE));
+
cpuhp_setup_state_multi(CPUHP_BLK_MQ_DEAD, "block/mq:dead", NULL,
blk_mq_hctx_notify_dead);
return 0;
diff --git a/block/blk-mq.h b/block/blk-mq.h
index 4933af9d61f7..6c7c3ff5bf62 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -3,6 +3,7 @@
#define INT_BLK_MQ_H
#include "blk-stat.h"
+#include "blk-mq-tag.h"
struct blk_mq_tag_set;
@@ -26,16 +27,16 @@ struct blk_mq_ctx {
struct kobject kobj;
} ____cacheline_aligned_in_smp;
-void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
void blk_mq_freeze_queue(struct request_queue *q);
void blk_mq_free_queue(struct request_queue *q);
int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
void blk_mq_wake_waiters(struct request_queue *q);
-bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *);
+bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
-bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx);
bool blk_mq_get_driver_tag(struct request *rq, struct blk_mq_hw_ctx **hctx,
bool wait);
+struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *start);
/*
* Internal helpers for allocating/freeing the request map
@@ -55,7 +56,7 @@ int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
*/
void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
bool at_head);
-void blk_mq_request_bypass_insert(struct request *rq);
+void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);
void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
struct list_head *list);
@@ -109,7 +110,7 @@ static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
struct blk_mq_alloc_data {
/* input parameter */
struct request_queue *q;
- unsigned int flags;
+ blk_mq_req_flags_t flags;
unsigned int shallow_depth;
/* input & output parameter */
@@ -138,4 +139,53 @@ static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
unsigned int inflight[2]);
+static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
+{
+ struct request_queue *q = hctx->queue;
+
+ if (q->mq_ops->put_budget)
+ q->mq_ops->put_budget(hctx);
+}
+
+static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
+{
+ struct request_queue *q = hctx->queue;
+
+ if (q->mq_ops->get_budget)
+ return q->mq_ops->get_budget(hctx);
+ return true;
+}
+
+static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
+ struct request *rq)
+{
+ blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
+ rq->tag = -1;
+
+ if (rq->rq_flags & RQF_MQ_INFLIGHT) {
+ rq->rq_flags &= ~RQF_MQ_INFLIGHT;
+ atomic_dec(&hctx->nr_active);
+ }
+}
+
+static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
+ struct request *rq)
+{
+ if (rq->tag == -1 || rq->internal_tag == -1)
+ return;
+
+ __blk_mq_put_driver_tag(hctx, rq);
+}
+
+static inline void blk_mq_put_driver_tag(struct request *rq)
+{
+ struct blk_mq_hw_ctx *hctx;
+
+ if (rq->tag == -1 || rq->internal_tag == -1)
+ return;
+
+ hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
+ __blk_mq_put_driver_tag(hctx, rq);
+}
+
#endif
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 8559e9563c52..48ebe6be07b7 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -157,7 +157,7 @@ EXPORT_SYMBOL(blk_set_stacking_limits);
* Caveat:
* The driver that does this *must* be able to deal appropriately
* with buffers in "highmemory". This can be accomplished by either calling
- * __bio_kmap_atomic() to get a temporary kernel mapping, or by calling
+ * kmap_atomic() to get a temporary kernel mapping, or by calling
* blk_queue_bounce() to create a buffer in normal memory.
**/
void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
diff --git a/block/blk-stat.c b/block/blk-stat.c
index c52356d90fe3..3a2f3c96f367 100644
--- a/block/blk-stat.c
+++ b/block/blk-stat.c
@@ -11,8 +11,6 @@
#include "blk-mq.h"
#include "blk.h"
-#define BLK_RQ_STAT_BATCH 64
-
struct blk_queue_stats {
struct list_head callbacks;
spinlock_t lock;
@@ -23,45 +21,21 @@ static void blk_stat_init(struct blk_rq_stat *stat)
{
stat->min = -1ULL;
stat->max = stat->nr_samples = stat->mean = 0;
- stat->batch = stat->nr_batch = 0;
-}
-
-static void blk_stat_flush_batch(struct blk_rq_stat *stat)
-{
- const s32 nr_batch = READ_ONCE(stat->nr_batch);
- const s32 nr_samples = READ_ONCE(stat->nr_samples);
-
- if (!nr_batch)
- return;
- if (!nr_samples)
- stat->mean = div64_s64(stat->batch, nr_batch);
- else {
- stat->mean = div64_s64((stat->mean * nr_samples) +
- stat->batch,
- nr_batch + nr_samples);
- }
-
- stat->nr_samples += nr_batch;
- stat->nr_batch = stat->batch = 0;
+ stat->batch = 0;
}
+/* src is a per-cpu stat, mean isn't initialized */
static void blk_stat_sum(struct blk_rq_stat *dst, struct blk_rq_stat *src)
{
- blk_stat_flush_batch(src);
-
if (!src->nr_samples)
return;
dst->min = min(dst->min, src->min);
dst->max = max(dst->max, src->max);
- if (!dst->nr_samples)
- dst->mean = src->mean;
- else {
- dst->mean = div64_s64((src->mean * src->nr_samples) +
- (dst->mean * dst->nr_samples),
- dst->nr_samples + src->nr_samples);
- }
+ dst->mean = div_u64(src->batch + dst->mean * dst->nr_samples,
+ dst->nr_samples + src->nr_samples);
+
dst->nr_samples += src->nr_samples;
}
@@ -69,13 +43,8 @@ static void __blk_stat_add(struct blk_rq_stat *stat, u64 value)
{
stat->min = min(stat->min, value);
stat->max = max(stat->max, value);
-
- if (stat->batch + value < stat->batch ||
- stat->nr_batch + 1 == BLK_RQ_STAT_BATCH)
- blk_stat_flush_batch(stat);
-
stat->batch += value;
- stat->nr_batch++;
+ stat->nr_samples++;
}
void blk_stat_add(struct request *rq)
@@ -84,7 +53,7 @@ void blk_stat_add(struct request *rq)
struct blk_stat_callback *cb;
struct blk_rq_stat *stat;
int bucket;
- s64 now, value;
+ u64 now, value;
now = __blk_stat_time(ktime_to_ns(ktime_get()));
if (now < blk_stat_time(&rq->issue_stat))
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 8631763866c6..96ad32623427 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -2113,8 +2113,12 @@ static inline void throtl_update_latency_buckets(struct throtl_data *td)
static void blk_throtl_assoc_bio(struct throtl_grp *tg, struct bio *bio)
{
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
- if (bio->bi_css)
+ if (bio->bi_css) {
+ if (bio->bi_cg_private)
+ blkg_put(tg_to_blkg(bio->bi_cg_private));
bio->bi_cg_private = tg;
+ blkg_get(tg_to_blkg(tg));
+ }
blk_stat_set_issue(&bio->bi_issue_stat, bio_sectors(bio));
#endif
}
@@ -2284,8 +2288,10 @@ void blk_throtl_bio_endio(struct bio *bio)
start_time = blk_stat_time(&bio->bi_issue_stat) >> 10;
finish_time = __blk_stat_time(finish_time_ns) >> 10;
- if (!start_time || finish_time <= start_time)
+ if (!start_time || finish_time <= start_time) {
+ blkg_put(tg_to_blkg(tg));
return;
+ }
lat = finish_time - start_time;
/* this is only for bio based driver */
@@ -2315,6 +2321,8 @@ void blk_throtl_bio_endio(struct bio *bio)
tg->bio_cnt /= 2;
tg->bad_bio_cnt /= 2;
}
+
+ blkg_put(tg_to_blkg(tg));
}
#endif
diff --git a/block/blk-timeout.c b/block/blk-timeout.c
index 17ec83bb0900..764ecf9aeb30 100644
--- a/block/blk-timeout.c
+++ b/block/blk-timeout.c
@@ -134,8 +134,6 @@ void blk_timeout_work(struct work_struct *work)
struct request *rq, *tmp;
int next_set = 0;
- if (blk_queue_enter(q, true))
- return;
spin_lock_irqsave(q->queue_lock, flags);
list_for_each_entry_safe(rq, tmp, &q->timeout_list, timeout_list)
@@ -145,7 +143,6 @@ void blk_timeout_work(struct work_struct *work)
mod_timer(&q->timeout, round_jiffies_up(next));
spin_unlock_irqrestore(q->queue_lock, flags);
- blk_queue_exit(q);
}
/**
@@ -211,7 +208,7 @@ void blk_add_timer(struct request *req)
if (!req->timeout)
req->timeout = q->rq_timeout;
- req->deadline = jiffies + req->timeout;
+ WRITE_ONCE(req->deadline, jiffies + req->timeout);
/*
* Only the non-mq case needs to add the request to a protected list.
diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index d822530e6aea..b252da0e4c11 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -654,7 +654,7 @@ void wbt_set_write_cache(struct rq_wb *rwb, bool write_cache_on)
}
/*
- * Disable wbt, if enabled by default. Only called from CFQ.
+ * Disable wbt, if enabled by default.
*/
void wbt_disable_default(struct request_queue *q)
{
diff --git a/block/blk.h b/block/blk.h
index 85be8b232b37..3f1446937aec 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -123,8 +123,15 @@ void blk_account_io_done(struct request *req);
* Internal atomic flags for request handling
*/
enum rq_atomic_flags {
+ /*
+ * Keep these two bits first - not because we depend on the
+ * value of them, but we do depend on them being in the same
+ * byte of storage to ensure ordering on writes. Keeping them
+ * first will achieve that nicely.
+ */
REQ_ATOM_COMPLETE = 0,
REQ_ATOM_STARTED,
+
REQ_ATOM_POLL_SLEPT,
};
@@ -149,45 +156,6 @@ static inline void blk_clear_rq_complete(struct request *rq)
void blk_insert_flush(struct request *rq);
-static inline struct request *__elv_next_request(struct request_queue *q)
-{
- struct request *rq;
- struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL);
-
- WARN_ON_ONCE(q->mq_ops);
-
- while (1) {
- if (!list_empty(&q->queue_head)) {
- rq = list_entry_rq(q->queue_head.next);
- return rq;
- }
-
- /*
- * Flush request is running and flush request isn't queueable
- * in the drive, we can hold the queue till flush request is
- * finished. Even we don't do this, driver can't dispatch next
- * requests and will requeue them. And this can improve
- * throughput too. For example, we have request flush1, write1,
- * flush 2. flush1 is dispatched, then queue is hold, write1
- * isn't inserted to queue. After flush1 is finished, flush2
- * will be dispatched. Since disk cache is already clean,
- * flush2 will be finished very soon, so looks like flush2 is
- * folded to flush1.
- * Since the queue is hold, a flag is set to indicate the queue
- * should be restarted later. Please see flush_end_io() for
- * details.
- */
- if (fq->flush_pending_idx != fq->flush_running_idx &&
- !queue_flush_queueable(q)) {
- fq->flush_queue_delayed = 1;
- return NULL;
- }
- if (unlikely(blk_queue_bypass(q)) ||
- !q->elevator->type->ops.sq.elevator_dispatch_fn(q, 0))
- return NULL;
- }
-}
-
static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
diff --git a/block/bsg.c b/block/bsg.c
index ee1335c68de7..452f94f1c5d4 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -137,7 +137,7 @@ static inline struct hlist_head *bsg_dev_idx_hash(int index)
static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
struct sg_io_v4 *hdr, struct bsg_device *bd,
- fmode_t has_write_perm)
+ fmode_t mode)
{
struct scsi_request *req = scsi_req(rq);
@@ -152,7 +152,7 @@ static int blk_fill_sgv4_hdr_rq(struct request_queue *q, struct request *rq,
return -EFAULT;
if (hdr->subprotocol == BSG_SUB_PROTOCOL_SCSI_CMD) {
- if (blk_verify_command(req->cmd, has_write_perm))
+ if (blk_verify_command(req->cmd, mode))
return -EPERM;
} else if (!capable(CAP_SYS_RAWIO))
return -EPERM;
@@ -206,7 +206,7 @@ bsg_validate_sgv4_hdr(struct sg_io_v4 *hdr, int *op)
* map sg_io_v4 to a request.
*/
static struct request *
-bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm)
+bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t mode)
{
struct request_queue *q = bd->queue;
struct request *rq, *next_rq = NULL;
@@ -237,7 +237,7 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, fmode_t has_write_perm)
if (IS_ERR(rq))
return rq;
- ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, has_write_perm);
+ ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, bd, mode);
if (ret)
goto out;
@@ -587,8 +587,7 @@ bsg_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
}
static int __bsg_write(struct bsg_device *bd, const char __user *buf,
- size_t count, ssize_t *bytes_written,
- fmode_t has_write_perm)
+ size_t count, ssize_t *bytes_written, fmode_t mode)
{
struct bsg_command *bc;
struct request *rq;
@@ -619,7 +618,7 @@ static int __bsg_write(struct bsg_device *bd, const char __user *buf,
/*
* get a request, fill in the blanks, and add to request queue
*/
- rq = bsg_map_hdr(bd, &bc->hdr, has_write_perm);
+ rq = bsg_map_hdr(bd, &bc->hdr, mode);
if (IS_ERR(rq)) {
ret = PTR_ERR(rq);
rq = NULL;
@@ -655,8 +654,7 @@ bsg_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
bsg_set_block(bd, file);
bytes_written = 0;
- ret = __bsg_write(bd, buf, count, &bytes_written,
- file->f_mode & FMODE_WRITE);
+ ret = __bsg_write(bd, buf, count, &bytes_written, file->f_mode);
*ppos = bytes_written;
@@ -915,7 +913,7 @@ static long bsg_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (copy_from_user(&hdr, uarg, sizeof(hdr)))
return -EFAULT;
- rq = bsg_map_hdr(bd, &hdr, file->f_mode & FMODE_WRITE);
+ rq = bsg_map_hdr(bd, &hdr, file->f_mode);
if (IS_ERR(rq))
return PTR_ERR(rq);
diff --git a/block/elevator.c b/block/elevator.c
index 153926a90901..7bda083d5968 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -83,12 +83,25 @@ bool elv_bio_merge_ok(struct request *rq, struct bio *bio)
}
EXPORT_SYMBOL(elv_bio_merge_ok);
-static struct elevator_type *elevator_find(const char *name)
+static bool elevator_match(const struct elevator_type *e, const char *name)
+{
+ if (!strcmp(e->elevator_name, name))
+ return true;
+ if (e->elevator_alias && !strcmp(e->elevator_alias, name))
+ return true;
+
+ return false;
+}
+
+/*
+ * Return scheduler with name 'name' and with matching 'mq capability
+ */
+static struct elevator_type *elevator_find(const char *name, bool mq)
{
struct elevator_type *e;
list_for_each_entry(e, &elv_list, list) {
- if (!strcmp(e->elevator_name, name))
+ if (elevator_match(e, name) && (mq == e->uses_mq))
return e;
}
@@ -100,25 +113,25 @@ static void elevator_put(struct elevator_type *e)
module_put(e->elevator_owner);
}
-static struct elevator_type *elevator_get(const char *name, bool try_loading)
+static struct elevator_type *elevator_get(struct request_queue *q,
+ const char *name, bool try_loading)
{
struct elevator_type *e;
spin_lock(&elv_list_lock);
- e = elevator_find(name);
+ e = elevator_find(name, q->mq_ops != NULL);
if (!e && try_loading) {
spin_unlock(&elv_list_lock);
request_module("%s-iosched", name);
spin_lock(&elv_list_lock);
- e = elevator_find(name);
+ e = elevator_find(name, q->mq_ops != NULL);
}
if (e && !try_module_get(e->elevator_owner))
e = NULL;
spin_unlock(&elv_list_lock);
-
return e;
}
@@ -144,8 +157,12 @@ void __init load_default_elevator_module(void)
if (!chosen_elevator[0])
return;
+ /*
+ * Boot parameter is deprecated, we haven't supported that for MQ.
+ * Only look for non-mq schedulers from here.
+ */
spin_lock(&elv_list_lock);
- e = elevator_find(chosen_elevator);
+ e = elevator_find(chosen_elevator, false);
spin_unlock(&elv_list_lock);
if (!e)
@@ -202,7 +219,7 @@ int elevator_init(struct request_queue *q, char *name)
q->boundary_rq = NULL;
if (name) {
- e = elevator_get(name, true);
+ e = elevator_get(q, name, true);
if (!e)
return -EINVAL;
}
@@ -214,7 +231,7 @@ int elevator_init(struct request_queue *q, char *name)
* allowed from async.
*/
if (!e && !q->mq_ops && *chosen_elevator) {
- e = elevator_get(chosen_elevator, false);
+ e = elevator_get(q, chosen_elevator, false);
if (!e)
printk(KERN_ERR "I/O scheduler %s not found\n",
chosen_elevator);
@@ -229,17 +246,17 @@ int elevator_init(struct request_queue *q, char *name)
*/
if (q->mq_ops) {
if (q->nr_hw_queues == 1)
- e = elevator_get("mq-deadline", false);
+ e = elevator_get(q, "mq-deadline", false);
if (!e)
return 0;
} else
- e = elevator_get(CONFIG_DEFAULT_IOSCHED, false);
+ e = elevator_get(q, CONFIG_DEFAULT_IOSCHED, false);
if (!e) {
printk(KERN_ERR
"Default I/O scheduler not found. " \
"Using noop.\n");
- e = elevator_get("noop", false);
+ e = elevator_get(q, "noop", false);
}
}
@@ -905,7 +922,7 @@ int elv_register(struct elevator_type *e)
/* register, don't allow duplicate names */
spin_lock(&elv_list_lock);
- if (elevator_find(e->elevator_name)) {
+ if (elevator_find(e->elevator_name, e->uses_mq)) {
spin_unlock(&elv_list_lock);
if (e->icq_cache)
kmem_cache_destroy(e->icq_cache);
@@ -915,9 +932,9 @@ int elv_register(struct elevator_type *e)
spin_unlock(&elv_list_lock);
/* print pretty message */
- if (!strcmp(e->elevator_name, chosen_elevator) ||
+ if (elevator_match(e, chosen_elevator) ||
(!*chosen_elevator &&
- !strcmp(e->elevator_name, CONFIG_DEFAULT_IOSCHED)))
+ elevator_match(e, CONFIG_DEFAULT_IOSCHED)))
def = " (default)";
printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name,
@@ -1066,25 +1083,15 @@ static int __elevator_change(struct request_queue *q, const char *name)
return elevator_switch(q, NULL);
strlcpy(elevator_name, name, sizeof(elevator_name));
- e = elevator_get(strstrip(elevator_name), true);
+ e = elevator_get(q, strstrip(elevator_name), true);
if (!e)
return -EINVAL;
- if (q->elevator &&
- !strcmp(elevator_name, q->elevator->type->elevator_name)) {
+ if (q->elevator && elevator_match(q->elevator->type, elevator_name)) {
elevator_put(e);
return 0;
}
- if (!e->uses_mq && q->mq_ops) {
- elevator_put(e);
- return -EINVAL;
- }
- if (e->uses_mq && !q->mq_ops) {
- elevator_put(e);
- return -EINVAL;
- }
-
return elevator_switch(q, e);
}
@@ -1116,9 +1123,10 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name)
struct elevator_queue *e = q->elevator;
struct elevator_type *elv = NULL;
struct elevator_type *__e;
+ bool uses_mq = q->mq_ops != NULL;
int len = 0;
- if (!blk_queue_stackable(q))
+ if (!queue_is_rq_based(q))
return sprintf(name, "none\n");
if (!q->elevator)
@@ -1128,7 +1136,8 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name)
spin_lock(&elv_list_lock);
list_for_each_entry(__e, &elv_list, list) {
- if (elv && !strcmp(elv->elevator_name, __e->elevator_name)) {
+ if (elv && elevator_match(elv, __e->elevator_name) &&
+ (__e->uses_mq == uses_mq)) {
len += sprintf(name+len, "[%s] ", elv->elevator_name);
continue;
}
diff --git a/block/genhd.c b/block/genhd.c
index 630c0da6cfcf..c2223f12a805 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -588,6 +588,11 @@ static void register_disk(struct device *parent, struct gendisk *disk)
disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
+ if (disk->flags & GENHD_FL_HIDDEN) {
+ dev_set_uevent_suppress(ddev, 0);
+ return;
+ }
+
/* No minors to use for partitions */
if (!disk_part_scan_enabled(disk))
goto exit;
@@ -616,6 +621,11 @@ exit:
while ((part = disk_part_iter_next(&piter)))
kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
disk_part_iter_exit(&piter);
+
+ err = sysfs_create_link(&ddev->kobj,
+ &disk->queue->backing_dev_info->dev->kobj,
+ "bdi");
+ WARN_ON(err);
}
/**
@@ -630,7 +640,6 @@ exit:
*/
void device_add_disk(struct device *parent, struct gendisk *disk)
{
- struct backing_dev_info *bdi;
dev_t devt;
int retval;
@@ -639,7 +648,8 @@ void device_add_disk(struct device *parent, struct gendisk *disk)
* parameters make sense.
*/
WARN_ON(disk->minors && !(disk->major || disk->first_minor));
- WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
+ WARN_ON(!disk->minors &&
+ !(disk->flags & (GENHD_FL_EXT_DEVT | GENHD_FL_HIDDEN)));
disk->flags |= GENHD_FL_UP;
@@ -648,22 +658,26 @@ void device_add_disk(struct device *parent, struct gendisk *disk)
WARN_ON(1);
return;
}
- disk_to_dev(disk)->devt = devt;
-
- /* ->major and ->first_minor aren't supposed to be
- * dereferenced from here on, but set them just in case.
- */
disk->major = MAJOR(devt);
disk->first_minor = MINOR(devt);
disk_alloc_events(disk);
- /* Register BDI before referencing it from bdev */
- bdi = disk->queue->backing_dev_info;
- bdi_register_owner(bdi, disk_to_dev(disk));
-
- blk_register_region(disk_devt(disk), disk->minors, NULL,
- exact_match, exact_lock, disk);
+ if (disk->flags & GENHD_FL_HIDDEN) {
+ /*
+ * Don't let hidden disks show up in /proc/partitions,
+ * and don't bother scanning for partitions either.
+ */
+ disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
+ disk->flags |= GENHD_FL_NO_PART_SCAN;
+ } else {
+ /* Register BDI before referencing it from bdev */
+ disk_to_dev(disk)->devt = devt;
+ bdi_register_owner(disk->queue->backing_dev_info,
+ disk_to_dev(disk));
+ blk_register_region(disk_devt(disk), disk->minors, NULL,
+ exact_match, exact_lock, disk);
+ }
register_disk(parent, disk);
blk_register_queue(disk);
@@ -673,10 +687,6 @@ void device_add_disk(struct device *parent, struct gendisk *disk)
*/
WARN_ON_ONCE(!blk_get_queue(disk->queue));
- retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
- "bdi");
- WARN_ON(retval);
-
disk_add_events(disk);
blk_integrity_add(disk);
}
@@ -705,7 +715,8 @@ void del_gendisk(struct gendisk *disk)
set_capacity(disk, 0);
disk->flags &= ~GENHD_FL_UP;
- sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
+ if (!(disk->flags & GENHD_FL_HIDDEN))
+ sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
if (disk->queue) {
/*
* Unregister bdi before releasing device numbers (as they can
@@ -716,13 +727,15 @@ void del_gendisk(struct gendisk *disk)
} else {
WARN_ON(1);
}
- blk_unregister_region(disk_devt(disk), disk->minors);
- part_stat_set_all(&disk->part0, 0);
- disk->part0.stamp = 0;
+ if (!(disk->flags & GENHD_FL_HIDDEN))
+ blk_unregister_region(disk_devt(disk), disk->minors);
kobject_put(disk->part0.holder_dir);
kobject_put(disk->slave_dir);
+
+ part_stat_set_all(&disk->part0, 0);
+ disk->part0.stamp = 0;
if (!sysfs_deprecated)
sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
@@ -785,6 +798,10 @@ struct gendisk *get_gendisk(dev_t devt, int *partno)
spin_unlock_bh(&ext_devt_lock);
}
+ if (disk && unlikely(disk->flags & GENHD_FL_HIDDEN)) {
+ put_disk(disk);
+ disk = NULL;
+ }
return disk;
}
EXPORT_SYMBOL(get_gendisk);
@@ -1028,6 +1045,15 @@ static ssize_t disk_removable_show(struct device *dev,
(disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
}
+static ssize_t disk_hidden_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct gendisk *disk = dev_to_disk(dev);
+
+ return sprintf(buf, "%d\n",
+ (disk->flags & GENHD_FL_HIDDEN ? 1 : 0));
+}
+
static ssize_t disk_ro_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -1065,6 +1091,7 @@ static ssize_t disk_discard_alignment_show(struct device *dev,
static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
+static DEVICE_ATTR(hidden, S_IRUGO, disk_hidden_show, NULL);
static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
@@ -1089,6 +1116,7 @@ static struct attribute *disk_attrs[] = {
&dev_attr_range.attr,
&dev_attr_ext_range.attr,
&dev_attr_removable.attr,
+ &dev_attr_hidden.attr,
&dev_attr_ro.attr,
&dev_attr_size.attr,
&dev_attr_alignment_offset.attr,
diff --git a/block/ioctl.c b/block/ioctl.c
index 0de02ee67eed..1668506d8ed8 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -202,10 +202,16 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
{
uint64_t range[2];
uint64_t start, len;
+ struct request_queue *q = bdev_get_queue(bdev);
+ struct address_space *mapping = bdev->bd_inode->i_mapping;
+
if (!(mode & FMODE_WRITE))
return -EBADF;
+ if (!blk_queue_discard(q))
+ return -EOPNOTSUPP;
+
if (copy_from_user(range, (void __user *)arg, sizeof(range)))
return -EFAULT;
@@ -216,12 +222,12 @@ static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
return -EINVAL;
if (len & 511)
return -EINVAL;
- start >>= 9;
- len >>= 9;
- if (start + len > (i_size_read(bdev->bd_inode) >> 9))
+ if (start + len > i_size_read(bdev->bd_inode))
return -EINVAL;
- return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags);
+ truncate_inode_pages_range(mapping, start, start + len);
+ return blkdev_issue_discard(bdev, start >> 9, len >> 9,
+ GFP_KERNEL, flags);
}
static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
@@ -437,11 +443,12 @@ static int blkdev_roset(struct block_device *bdev, fmode_t mode,
{
int ret, n;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+
ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
if (!is_unrecognized_ioctl(ret))
return ret;
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
if (get_user(n, (int __user *)arg))
return -EFAULT;
set_device_ro(bdev, n);
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index f58cab82105b..b4df317c2916 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -541,9 +541,17 @@ static int kyber_get_domain_token(struct kyber_queue_data *kqd,
/*
* Try again in case a token was freed before we got on the wait
- * queue.
+ * queue. The waker may have already removed the entry from the
+ * wait queue, but list_del_init() is okay with that.
*/
nr = __sbitmap_queue_get(domain_tokens);
+ if (nr >= 0) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&ws->wait.lock, flags);
+ list_del_init(&wait->entry);
+ spin_unlock_irqrestore(&ws->wait.lock, flags);
+ }
}
return nr;
}
@@ -641,7 +649,7 @@ static bool kyber_has_work(struct blk_mq_hw_ctx *hctx)
if (!list_empty_careful(&khd->rqs[i]))
return true;
}
- return false;
+ return sbitmap_any_bit_set(&hctx->ctx_map);
}
#define KYBER_LAT_SHOW_STORE(op) \
diff --git a/block/mq-deadline.c b/block/mq-deadline.c
index a1cad4331edd..0179e484ec98 100644
--- a/block/mq-deadline.c
+++ b/block/mq-deadline.c
@@ -657,6 +657,7 @@ static struct elevator_type mq_deadline = {
#endif
.elevator_attrs = deadline_attrs,
.elevator_name = "mq-deadline",
+ .elevator_alias = "deadline",
.elevator_owner = THIS_MODULE,
};
MODULE_ALIAS("mq-deadline-iosched");
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 7440de44dd85..edcfff974527 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -207,7 +207,7 @@ static void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter)
__set_bit(GPCMD_SET_READ_AHEAD, filter->write_ok);
}
-int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
+int blk_verify_command(unsigned char *cmd, fmode_t mode)
{
struct blk_cmd_filter *filter = &blk_default_cmd_filter;
@@ -220,7 +220,7 @@ int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm)
return 0;
/* Write-safe commands require a writable open */
- if (test_bit(cmd[0], filter->write_ok) && has_write_perm)
+ if (test_bit(cmd[0], filter->write_ok) && (mode & FMODE_WRITE))
return 0;
return -EPERM;
@@ -234,7 +234,7 @@ static int blk_fill_sghdr_rq(struct request_queue *q, struct request *rq,
if (copy_from_user(req->cmd, hdr->cmdp, hdr->cmd_len))
return -EFAULT;
- if (blk_verify_command(req->cmd, mode & FMODE_WRITE))
+ if (blk_verify_command(req->cmd, mode))
return -EPERM;
/*
@@ -469,7 +469,7 @@ int sg_scsi_ioctl(struct request_queue *q, struct gendisk *disk, fmode_t mode,
if (in_len && copy_from_user(buffer, sic->data + cmdlen, in_len))
goto error;
- err = blk_verify_command(req->cmd, mode & FMODE_WRITE);
+ err = blk_verify_command(req->cmd, mode);
if (err)
goto error;