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Diffstat (limited to 'block/blk-core.c')
-rw-r--r--block/blk-core.c404
1 files changed, 162 insertions, 242 deletions
diff --git a/block/blk-core.c b/block/blk-core.c
index 4d8f5fe91588..fd389a16013c 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -18,6 +18,7 @@
#include <linux/blkdev.h>
#include <linux/blk-mq.h>
#include <linux/blk-pm.h>
+#include <linux/blk-integrity.h>
#include <linux/highmem.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
@@ -49,6 +50,7 @@
#include "blk-mq.h"
#include "blk-mq-sched.h"
#include "blk-pm.h"
+#include "blk-throttle.h"
struct dentry *blk_debugfs_root;
@@ -214,8 +216,7 @@ int blk_status_to_errno(blk_status_t status)
}
EXPORT_SYMBOL_GPL(blk_status_to_errno);
-static void print_req_error(struct request *req, blk_status_t status,
- const char *caller)
+void blk_print_req_error(struct request *req, blk_status_t status)
{
int idx = (__force int)status;
@@ -223,9 +224,9 @@ static void print_req_error(struct request *req, blk_status_t status,
return;
printk_ratelimited(KERN_ERR
- "%s: %s error, dev %s, sector %llu op 0x%x:(%s) flags 0x%x "
+ "%s error, dev %s, sector %llu op 0x%x:(%s) flags 0x%x "
"phys_seg %u prio class %u\n",
- caller, blk_errors[idx].name,
+ blk_errors[idx].name,
req->rq_disk ? req->rq_disk->disk_name : "?",
blk_rq_pos(req), req_op(req), blk_op_str(req_op(req)),
req->cmd_flags & ~REQ_OP_MASK,
@@ -233,33 +234,6 @@ static void print_req_error(struct request *req, blk_status_t status,
IOPRIO_PRIO_CLASS(req->ioprio));
}
-static void req_bio_endio(struct request *rq, struct bio *bio,
- unsigned int nbytes, blk_status_t error)
-{
- if (error)
- bio->bi_status = error;
-
- if (unlikely(rq->rq_flags & RQF_QUIET))
- bio_set_flag(bio, BIO_QUIET);
-
- bio_advance(bio, nbytes);
-
- if (req_op(rq) == REQ_OP_ZONE_APPEND && error == BLK_STS_OK) {
- /*
- * Partial zone append completions cannot be supported as the
- * BIO fragments may end up not being written sequentially.
- */
- if (bio->bi_iter.bi_size)
- bio->bi_status = BLK_STS_IOERR;
- else
- bio->bi_iter.bi_sector = rq->__sector;
- }
-
- /* don't actually finish bio if it's part of flush sequence */
- if (bio->bi_iter.bi_size == 0 && !(rq->rq_flags & RQF_FLUSH_SEQ))
- bio_endio(bio);
-}
-
void blk_dump_rq_flags(struct request *rq, char *msg)
{
printk(KERN_INFO "%s: dev %s: flags=%llx\n", msg,
@@ -402,7 +376,7 @@ void blk_cleanup_queue(struct request_queue *q)
*/
mutex_lock(&q->sysfs_lock);
if (q->elevator)
- blk_mq_sched_free_requests(q);
+ blk_mq_sched_free_rqs(q);
mutex_unlock(&q->sysfs_lock);
percpu_ref_exit(&q->q_usage_counter);
@@ -415,7 +389,7 @@ EXPORT_SYMBOL(blk_cleanup_queue);
static bool blk_try_enter_queue(struct request_queue *q, bool pm)
{
rcu_read_lock();
- if (!percpu_ref_tryget_live(&q->q_usage_counter))
+ if (!percpu_ref_tryget_live_rcu(&q->q_usage_counter))
goto fail;
/*
@@ -430,7 +404,7 @@ static bool blk_try_enter_queue(struct request_queue *q, bool pm)
return true;
fail_put:
- percpu_ref_put(&q->q_usage_counter);
+ blk_queue_exit(q);
fail:
rcu_read_unlock();
return false;
@@ -470,10 +444,11 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
static inline int bio_queue_enter(struct bio *bio)
{
- struct gendisk *disk = bio->bi_bdev->bd_disk;
- struct request_queue *q = disk->queue;
+ struct request_queue *q = bdev_get_queue(bio->bi_bdev);
while (!blk_try_enter_queue(q, false)) {
+ struct gendisk *disk = bio->bi_bdev->bd_disk;
+
if (bio->bi_opf & REQ_NOWAIT) {
if (test_bit(GD_DEAD, &disk->state))
goto dead;
@@ -553,7 +528,7 @@ struct request_queue *blk_alloc_queue(int node_id)
q->node = node_id;
- atomic_set(&q->nr_active_requests_shared_sbitmap, 0);
+ atomic_set(&q->nr_active_requests_shared_tags, 0);
timer_setup(&q->timeout, blk_rq_timed_out_timer, 0);
INIT_WORK(&q->timeout_work, blk_timeout_work);
@@ -586,7 +561,7 @@ struct request_queue *blk_alloc_queue(int node_id)
blk_queue_dma_alignment(q, 511);
blk_set_default_limits(&q->limits);
- q->nr_requests = BLKDEV_MAX_RQ;
+ q->nr_requests = BLKDEV_DEFAULT_RQ;
return q;
@@ -654,8 +629,9 @@ static void handle_bad_sector(struct bio *bio, sector_t maxsector)
{
char b[BDEVNAME_SIZE];
- pr_info_ratelimited("attempt to access beyond end of device\n"
+ pr_info_ratelimited("%s: attempt to access beyond end of device\n"
"%s: rw=%d, want=%llu, limit=%llu\n",
+ current->comm,
bio_devname(bio, b), bio->bi_opf,
bio_end_sector(bio), maxsector);
}
@@ -797,7 +773,7 @@ static inline blk_status_t blk_check_zone_append(struct request_queue *q,
static noinline_for_stack bool submit_bio_checks(struct bio *bio)
{
struct block_device *bdev = bio->bi_bdev;
- struct request_queue *q = bdev->bd_disk->queue;
+ struct request_queue *q = bdev_get_queue(bdev);
blk_status_t status = BLK_STS_IOERR;
struct blk_plug *plug;
@@ -839,7 +815,7 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio)
}
if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
- bio_clear_hipri(bio);
+ bio_clear_polled(bio);
switch (bio_op(bio)) {
case REQ_OP_DISCARD:
@@ -912,25 +888,22 @@ end_io:
return false;
}
-static blk_qc_t __submit_bio(struct bio *bio)
+static void __submit_bio(struct bio *bio)
{
struct gendisk *disk = bio->bi_bdev->bd_disk;
- blk_qc_t ret = BLK_QC_T_NONE;
if (unlikely(bio_queue_enter(bio) != 0))
- return BLK_QC_T_NONE;
+ return;
if (!submit_bio_checks(bio) || !blk_crypto_bio_prep(&bio))
goto queue_exit;
- if (disk->fops->submit_bio) {
- ret = disk->fops->submit_bio(bio);
- goto queue_exit;
+ if (!disk->fops->submit_bio) {
+ blk_mq_submit_bio(bio);
+ return;
}
- return blk_mq_submit_bio(bio);
-
+ disk->fops->submit_bio(bio);
queue_exit:
blk_queue_exit(disk->queue);
- return ret;
}
/*
@@ -952,10 +925,9 @@ queue_exit:
* bio_list_on_stack[1] contains bios that were submitted before the current
* ->submit_bio_bio, but that haven't been processed yet.
*/
-static blk_qc_t __submit_bio_noacct(struct bio *bio)
+static void __submit_bio_noacct(struct bio *bio)
{
struct bio_list bio_list_on_stack[2];
- blk_qc_t ret = BLK_QC_T_NONE;
BUG_ON(bio->bi_next);
@@ -963,7 +935,7 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
current->bio_list = bio_list_on_stack;
do {
- struct request_queue *q = bio->bi_bdev->bd_disk->queue;
+ struct request_queue *q = bdev_get_queue(bio->bi_bdev);
struct bio_list lower, same;
/*
@@ -972,7 +944,7 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
bio_list_on_stack[1] = bio_list_on_stack[0];
bio_list_init(&bio_list_on_stack[0]);
- ret = __submit_bio(bio);
+ __submit_bio(bio);
/*
* Sort new bios into those for a lower level and those for the
@@ -981,7 +953,7 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
bio_list_init(&lower);
bio_list_init(&same);
while ((bio = bio_list_pop(&bio_list_on_stack[0])) != NULL)
- if (q == bio->bi_bdev->bd_disk->queue)
+ if (q == bdev_get_queue(bio->bi_bdev))
bio_list_add(&same, bio);
else
bio_list_add(&lower, bio);
@@ -995,22 +967,19 @@ static blk_qc_t __submit_bio_noacct(struct bio *bio)
} while ((bio = bio_list_pop(&bio_list_on_stack[0])));
current->bio_list = NULL;
- return ret;
}
-static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
+static void __submit_bio_noacct_mq(struct bio *bio)
{
struct bio_list bio_list[2] = { };
- blk_qc_t ret;
current->bio_list = bio_list;
do {
- ret = __submit_bio(bio);
+ __submit_bio(bio);
} while ((bio = bio_list_pop(&bio_list[0])));
current->bio_list = NULL;
- return ret;
}
/**
@@ -1022,7 +991,7 @@ static blk_qc_t __submit_bio_noacct_mq(struct bio *bio)
* systems and other upper level users of the block layer should use
* submit_bio() instead.
*/
-blk_qc_t submit_bio_noacct(struct bio *bio)
+void submit_bio_noacct(struct bio *bio)
{
/*
* We only want one ->submit_bio to be active at a time, else stack
@@ -1030,14 +999,12 @@ blk_qc_t submit_bio_noacct(struct bio *bio)
* to collect a list of requests submited by a ->submit_bio method while
* it is active, and then process them after it returned.
*/
- if (current->bio_list) {
+ if (current->bio_list)
bio_list_add(&current->bio_list[0], bio);
- return BLK_QC_T_NONE;
- }
-
- if (!bio->bi_bdev->bd_disk->fops->submit_bio)
- return __submit_bio_noacct_mq(bio);
- return __submit_bio_noacct(bio);
+ else if (!bio->bi_bdev->bd_disk->fops->submit_bio)
+ __submit_bio_noacct_mq(bio);
+ else
+ __submit_bio_noacct(bio);
}
EXPORT_SYMBOL(submit_bio_noacct);
@@ -1054,10 +1021,10 @@ EXPORT_SYMBOL(submit_bio_noacct);
* in @bio. The bio must NOT be touched by thecaller until ->bi_end_io() has
* been called.
*/
-blk_qc_t submit_bio(struct bio *bio)
+void submit_bio(struct bio *bio)
{
if (blkcg_punt_bio_submit(bio))
- return BLK_QC_T_NONE;
+ return;
/*
* If it's a regular read/write or a barrier with data attached,
@@ -1068,7 +1035,7 @@ blk_qc_t submit_bio(struct bio *bio)
if (unlikely(bio_op(bio) == REQ_OP_WRITE_SAME))
count = queue_logical_block_size(
- bio->bi_bdev->bd_disk->queue) >> 9;
+ bdev_get_queue(bio->bi_bdev)) >> 9;
else
count = bio_sectors(bio);
@@ -1089,20 +1056,93 @@ blk_qc_t submit_bio(struct bio *bio)
if (unlikely(bio_op(bio) == REQ_OP_READ &&
bio_flagged(bio, BIO_WORKINGSET))) {
unsigned long pflags;
- blk_qc_t ret;
psi_memstall_enter(&pflags);
- ret = submit_bio_noacct(bio);
+ submit_bio_noacct(bio);
psi_memstall_leave(&pflags);
-
- return ret;
+ return;
}
- return submit_bio_noacct(bio);
+ submit_bio_noacct(bio);
}
EXPORT_SYMBOL(submit_bio);
/**
+ * bio_poll - poll for BIO completions
+ * @bio: bio to poll for
+ * @flags: BLK_POLL_* flags that control the behavior
+ *
+ * Poll for completions on queue associated with the bio. Returns number of
+ * completed entries found.
+ *
+ * Note: the caller must either be the context that submitted @bio, or
+ * be in a RCU critical section to prevent freeing of @bio.
+ */
+int bio_poll(struct bio *bio, struct io_comp_batch *iob, unsigned int flags)
+{
+ struct request_queue *q = bdev_get_queue(bio->bi_bdev);
+ blk_qc_t cookie = READ_ONCE(bio->bi_cookie);
+ int ret;
+
+ if (cookie == BLK_QC_T_NONE ||
+ !test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
+ return 0;
+
+ if (current->plug)
+ blk_flush_plug(current->plug, false);
+
+ if (blk_queue_enter(q, BLK_MQ_REQ_NOWAIT))
+ return 0;
+ if (WARN_ON_ONCE(!queue_is_mq(q)))
+ ret = 0; /* not yet implemented, should not happen */
+ else
+ ret = blk_mq_poll(q, cookie, iob, flags);
+ blk_queue_exit(q);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bio_poll);
+
+/*
+ * Helper to implement file_operations.iopoll. Requires the bio to be stored
+ * in iocb->private, and cleared before freeing the bio.
+ */
+int iocb_bio_iopoll(struct kiocb *kiocb, struct io_comp_batch *iob,
+ unsigned int flags)
+{
+ struct bio *bio;
+ int ret = 0;
+
+ /*
+ * Note: the bio cache only uses SLAB_TYPESAFE_BY_RCU, so bio can
+ * point to a freshly allocated bio at this point. If that happens
+ * we have a few cases to consider:
+ *
+ * 1) the bio is beeing initialized and bi_bdev is NULL. We can just
+ * simply nothing in this case
+ * 2) the bio points to a not poll enabled device. bio_poll will catch
+ * this and return 0
+ * 3) the bio points to a poll capable device, including but not
+ * limited to the one that the original bio pointed to. In this
+ * case we will call into the actual poll method and poll for I/O,
+ * even if we don't need to, but it won't cause harm either.
+ *
+ * For cases 2) and 3) above the RCU grace period ensures that bi_bdev
+ * is still allocated. Because partitions hold a reference to the whole
+ * device bdev and thus disk, the disk is also still valid. Grabbing
+ * a reference to the queue in bio_poll() ensures the hctxs and requests
+ * are still valid as well.
+ */
+ rcu_read_lock();
+ bio = READ_ONCE(kiocb->private);
+ if (bio && bio->bi_bdev)
+ ret = bio_poll(bio, iob, flags);
+ rcu_read_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(iocb_bio_iopoll);
+
+/**
* blk_cloned_rq_check_limits - Helper function to check a cloned request
* for the new queue limits
* @q: the queue
@@ -1177,8 +1217,7 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request *
if (blk_crypto_insert_cloned_request(rq))
return BLK_STS_IOERR;
- if (blk_queue_io_stat(q))
- blk_account_io_start(rq);
+ blk_account_io_start(rq);
/*
* Since we have a scheduler attached on the top device,
@@ -1246,41 +1285,19 @@ again:
}
}
-static void blk_account_io_completion(struct request *req, unsigned int bytes)
+void __blk_account_io_done(struct request *req, u64 now)
{
- if (req->part && blk_do_io_stat(req)) {
- const int sgrp = op_stat_group(req_op(req));
-
- part_stat_lock();
- part_stat_add(req->part, sectors[sgrp], bytes >> 9);
- part_stat_unlock();
- }
-}
+ const int sgrp = op_stat_group(req_op(req));
-void blk_account_io_done(struct request *req, u64 now)
-{
- /*
- * Account IO completion. flush_rq isn't accounted as a
- * normal IO on queueing nor completion. Accounting the
- * containing request is enough.
- */
- if (req->part && blk_do_io_stat(req) &&
- !(req->rq_flags & RQF_FLUSH_SEQ)) {
- const int sgrp = op_stat_group(req_op(req));
-
- part_stat_lock();
- update_io_ticks(req->part, jiffies, true);
- part_stat_inc(req->part, ios[sgrp]);
- part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns);
- part_stat_unlock();
- }
+ part_stat_lock();
+ update_io_ticks(req->part, jiffies, true);
+ part_stat_inc(req->part, ios[sgrp]);
+ part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns);
+ part_stat_unlock();
}
-void blk_account_io_start(struct request *rq)
+void __blk_account_io_start(struct request *rq)
{
- if (!blk_do_io_stat(rq))
- return;
-
/* passthrough requests can hold bios that do not have ->bi_bdev set */
if (rq->bio && rq->bio->bi_bdev)
rq->part = rq->bio->bi_bdev;
@@ -1376,112 +1393,6 @@ void blk_steal_bios(struct bio_list *list, struct request *rq)
}
EXPORT_SYMBOL_GPL(blk_steal_bios);
-/**
- * blk_update_request - Complete multiple bytes without completing the request
- * @req: the request being processed
- * @error: block status code
- * @nr_bytes: number of bytes to complete for @req
- *
- * Description:
- * Ends I/O on a number of bytes attached to @req, but doesn't complete
- * the request structure even if @req doesn't have leftover.
- * If @req has leftover, sets it up for the next range of segments.
- *
- * Passing the result of blk_rq_bytes() as @nr_bytes guarantees
- * %false return from this function.
- *
- * Note:
- * The RQF_SPECIAL_PAYLOAD flag is ignored on purpose in this function
- * except in the consistency check at the end of this function.
- *
- * Return:
- * %false - this request doesn't have any more data
- * %true - this request has more data
- **/
-bool blk_update_request(struct request *req, blk_status_t error,
- unsigned int nr_bytes)
-{
- int total_bytes;
-
- trace_block_rq_complete(req, blk_status_to_errno(error), nr_bytes);
-
- if (!req->bio)
- return false;
-
-#ifdef CONFIG_BLK_DEV_INTEGRITY
- if (blk_integrity_rq(req) && req_op(req) == REQ_OP_READ &&
- error == BLK_STS_OK)
- req->q->integrity.profile->complete_fn(req, nr_bytes);
-#endif
-
- if (unlikely(error && !blk_rq_is_passthrough(req) &&
- !(req->rq_flags & RQF_QUIET)))
- print_req_error(req, error, __func__);
-
- blk_account_io_completion(req, nr_bytes);
-
- total_bytes = 0;
- while (req->bio) {
- struct bio *bio = req->bio;
- unsigned bio_bytes = min(bio->bi_iter.bi_size, nr_bytes);
-
- if (bio_bytes == bio->bi_iter.bi_size)
- req->bio = bio->bi_next;
-
- /* Completion has already been traced */
- bio_clear_flag(bio, BIO_TRACE_COMPLETION);
- req_bio_endio(req, bio, bio_bytes, error);
-
- total_bytes += bio_bytes;
- nr_bytes -= bio_bytes;
-
- if (!nr_bytes)
- break;
- }
-
- /*
- * completely done
- */
- if (!req->bio) {
- /*
- * Reset counters so that the request stacking driver
- * can find how many bytes remain in the request
- * later.
- */
- req->__data_len = 0;
- return false;
- }
-
- req->__data_len -= total_bytes;
-
- /* update sector only for requests with clear definition of sector */
- if (!blk_rq_is_passthrough(req))
- req->__sector += total_bytes >> 9;
-
- /* mixed attributes always follow the first bio */
- if (req->rq_flags & RQF_MIXED_MERGE) {
- req->cmd_flags &= ~REQ_FAILFAST_MASK;
- req->cmd_flags |= req->bio->bi_opf & REQ_FAILFAST_MASK;
- }
-
- if (!(req->rq_flags & RQF_SPECIAL_PAYLOAD)) {
- /*
- * If total number of sectors is less than the first segment
- * size, something has gone terribly wrong.
- */
- if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) {
- blk_dump_rq_flags(req, "request botched");
- req->__data_len = blk_rq_cur_bytes(req);
- }
-
- /* recalculate the number of segments */
- req->nr_phys_segments = blk_recalc_rq_segments(req);
- }
-
- return true;
-}
-EXPORT_SYMBOL_GPL(blk_update_request);
-
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
/**
* rq_flush_dcache_pages - Helper function to flush all pages in a request
@@ -1629,6 +1540,32 @@ int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork,
}
EXPORT_SYMBOL(kblockd_mod_delayed_work_on);
+void blk_start_plug_nr_ios(struct blk_plug *plug, unsigned short nr_ios)
+{
+ struct task_struct *tsk = current;
+
+ /*
+ * If this is a nested plug, don't actually assign it.
+ */
+ if (tsk->plug)
+ return;
+
+ plug->mq_list = NULL;
+ plug->cached_rq = NULL;
+ plug->nr_ios = min_t(unsigned short, nr_ios, BLK_MAX_REQUEST_COUNT);
+ plug->rq_count = 0;
+ plug->multiple_queues = false;
+ plug->has_elevator = false;
+ plug->nowait = false;
+ INIT_LIST_HEAD(&plug->cb_list);
+
+ /*
+ * Store ordering should not be needed here, since a potential
+ * preempt will imply a full memory barrier
+ */
+ tsk->plug = plug;
+}
+
/**
* blk_start_plug - initialize blk_plug and track it inside the task_struct
* @plug: The &struct blk_plug that needs to be initialized
@@ -1654,25 +1591,7 @@ EXPORT_SYMBOL(kblockd_mod_delayed_work_on);
*/
void blk_start_plug(struct blk_plug *plug)
{
- struct task_struct *tsk = current;
-
- /*
- * If this is a nested plug, don't actually assign it.
- */
- if (tsk->plug)
- return;
-
- INIT_LIST_HEAD(&plug->mq_list);
- INIT_LIST_HEAD(&plug->cb_list);
- plug->rq_count = 0;
- plug->multiple_queues = false;
- plug->nowait = false;
-
- /*
- * Store ordering should not be needed here, since a potential
- * preempt will imply a full memory barrier
- */
- tsk->plug = plug;
+ blk_start_plug_nr_ios(plug, 1);
}
EXPORT_SYMBOL(blk_start_plug);
@@ -1718,12 +1637,14 @@ struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, void *data,
}
EXPORT_SYMBOL(blk_check_plugged);
-void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
+void blk_flush_plug(struct blk_plug *plug, bool from_schedule)
{
- flush_plug_callbacks(plug, from_schedule);
-
- if (!list_empty(&plug->mq_list))
+ if (!list_empty(&plug->cb_list))
+ flush_plug_callbacks(plug, from_schedule);
+ if (!rq_list_empty(plug->mq_list))
blk_mq_flush_plug_list(plug, from_schedule);
+ if (unlikely(!from_schedule && plug->cached_rq))
+ blk_mq_free_plug_rqs(plug);
}
/**
@@ -1738,11 +1659,10 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
*/
void blk_finish_plug(struct blk_plug *plug)
{
- if (plug != current->plug)
- return;
- blk_flush_plug_list(plug, false);
-
- current->plug = NULL;
+ if (plug == current->plug) {
+ blk_flush_plug(plug, false);
+ current->plug = NULL;
+ }
}
EXPORT_SYMBOL(blk_finish_plug);