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authorLinus Torvalds <torvalds@linux-foundation.org>2009-09-15 04:55:15 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-15 04:55:15 +0400
commit355bbd8cb82e60a592f6cd86ce6dbe5677615cf4 (patch)
tree23678e50ad4687f1656edc972388ee8014e7b89d /block
parent39695224bd84dc4be29abad93a0ec232a16fc519 (diff)
parent746cd1e7e4a555ddaee53b19a46e05c9c61eaf09 (diff)
downloadlinux-355bbd8cb82e60a592f6cd86ce6dbe5677615cf4.tar.xz
Merge branch 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.32' of git://git.kernel.dk/linux-2.6-block: (29 commits) block: use blkdev_issue_discard in blk_ioctl_discard Make DISCARD_BARRIER and DISCARD_NOBARRIER writes instead of reads block: don't assume device has a request list backing in nr_requests store block: Optimal I/O limit wrapper cfq: choose a new next_req when a request is dispatched Seperate read and write statistics of in_flight requests aoe: end barrier bios with EOPNOTSUPP block: trace bio queueing trial only when it occurs block: enable rq CPU completion affinity by default cfq: fix the log message after dispatched a request block: use printk_once cciss: memory leak in cciss_init_one() splice: update mtime and atime on files block: make blk_iopoll_prep_sched() follow normal 0/1 return convention cfq-iosched: get rid of must_alloc flag block: use interrupts disabled version of raise_softirq_irqoff() block: fix comment in blk-iopoll.c block: adjust default budget for blk-iopoll block: fix long lines in block/blk-iopoll.c block: add blk-iopoll, a NAPI like approach for block devices ...
Diffstat (limited to 'block')
-rw-r--r--block/Makefile2
-rw-r--r--block/blk-barrier.c31
-rw-r--r--block/blk-core.c166
-rw-r--r--block/blk-iopoll.c227
-rw-r--r--block/blk-merge.c51
-rw-r--r--block/blk-settings.c21
-rw-r--r--block/blk-sysfs.c7
-rw-r--r--block/blk.h1
-rw-r--r--block/cfq-iosched.c72
-rw-r--r--block/elevator.c16
-rw-r--r--block/genhd.c22
-rw-r--r--block/ioctl.c49
12 files changed, 504 insertions, 161 deletions
diff --git a/block/Makefile b/block/Makefile
index 6c54ed0ff755..ba74ca6bfa14 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -5,7 +5,7 @@
obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \
blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
- ioctl.o genhd.o scsi_ioctl.o
+ blk-iopoll.o ioctl.o genhd.o scsi_ioctl.o
obj-$(CONFIG_BLK_DEV_BSG) += bsg.o
obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o
diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 30022b4e2f63..6593ab39cfe9 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -348,6 +348,9 @@ static void blkdev_discard_end_io(struct bio *bio, int err)
clear_bit(BIO_UPTODATE, &bio->bi_flags);
}
+ if (bio->bi_private)
+ complete(bio->bi_private);
+
bio_put(bio);
}
@@ -357,21 +360,20 @@ static void blkdev_discard_end_io(struct bio *bio, int err)
* @sector: start sector
* @nr_sects: number of sectors to discard
* @gfp_mask: memory allocation flags (for bio_alloc)
+ * @flags: DISCARD_FL_* flags to control behaviour
*
* Description:
- * Issue a discard request for the sectors in question. Does not wait.
+ * Issue a discard request for the sectors in question.
*/
-int blkdev_issue_discard(struct block_device *bdev,
- sector_t sector, sector_t nr_sects, gfp_t gfp_mask)
+int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
+ sector_t nr_sects, gfp_t gfp_mask, int flags)
{
- struct request_queue *q;
- struct bio *bio;
+ DECLARE_COMPLETION_ONSTACK(wait);
+ struct request_queue *q = bdev_get_queue(bdev);
+ int type = flags & DISCARD_FL_BARRIER ?
+ DISCARD_BARRIER : DISCARD_NOBARRIER;
int ret = 0;
- if (bdev->bd_disk == NULL)
- return -ENXIO;
-
- q = bdev_get_queue(bdev);
if (!q)
return -ENXIO;
@@ -379,12 +381,14 @@ int blkdev_issue_discard(struct block_device *bdev,
return -EOPNOTSUPP;
while (nr_sects && !ret) {
- bio = bio_alloc(gfp_mask, 0);
+ struct bio *bio = bio_alloc(gfp_mask, 0);
if (!bio)
return -ENOMEM;
bio->bi_end_io = blkdev_discard_end_io;
bio->bi_bdev = bdev;
+ if (flags & DISCARD_FL_WAIT)
+ bio->bi_private = &wait;
bio->bi_sector = sector;
@@ -396,10 +400,13 @@ int blkdev_issue_discard(struct block_device *bdev,
bio->bi_size = nr_sects << 9;
nr_sects = 0;
}
+
bio_get(bio);
- submit_bio(DISCARD_BARRIER, bio);
+ submit_bio(type, bio);
+
+ if (flags & DISCARD_FL_WAIT)
+ wait_for_completion(&wait);
- /* Check if it failed immediately */
if (bio_flagged(bio, BIO_EOPNOTSUPP))
ret = -EOPNOTSUPP;
else if (!bio_flagged(bio, BIO_UPTODATE))
diff --git a/block/blk-core.c b/block/blk-core.c
index e695634882a6..8135228e4b29 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -69,7 +69,7 @@ static void drive_stat_acct(struct request *rq, int new_io)
part_stat_inc(cpu, part, merges[rw]);
else {
part_round_stats(cpu, part);
- part_inc_in_flight(part);
+ part_inc_in_flight(part, rw);
}
part_stat_unlock();
@@ -1031,7 +1031,7 @@ static void part_round_stats_single(int cpu, struct hd_struct *part,
if (part->in_flight) {
__part_stat_add(cpu, part, time_in_queue,
- part->in_flight * (now - part->stamp));
+ part_in_flight(part) * (now - part->stamp));
__part_stat_add(cpu, part, io_ticks, (now - part->stamp));
}
part->stamp = now;
@@ -1112,31 +1112,27 @@ void init_request_from_bio(struct request *req, struct bio *bio)
req->cmd_type = REQ_TYPE_FS;
/*
- * inherit FAILFAST from bio (for read-ahead, and explicit FAILFAST)
+ * Inherit FAILFAST from bio (for read-ahead, and explicit
+ * FAILFAST). FAILFAST flags are identical for req and bio.
*/
- if (bio_rw_ahead(bio))
- req->cmd_flags |= (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
- REQ_FAILFAST_DRIVER);
- if (bio_failfast_dev(bio))
- req->cmd_flags |= REQ_FAILFAST_DEV;
- if (bio_failfast_transport(bio))
- req->cmd_flags |= REQ_FAILFAST_TRANSPORT;
- if (bio_failfast_driver(bio))
- req->cmd_flags |= REQ_FAILFAST_DRIVER;
-
- if (unlikely(bio_discard(bio))) {
+ if (bio_rw_flagged(bio, BIO_RW_AHEAD))
+ req->cmd_flags |= REQ_FAILFAST_MASK;
+ else
+ req->cmd_flags |= bio->bi_rw & REQ_FAILFAST_MASK;
+
+ if (unlikely(bio_rw_flagged(bio, BIO_RW_DISCARD))) {
req->cmd_flags |= REQ_DISCARD;
- if (bio_barrier(bio))
+ if (bio_rw_flagged(bio, BIO_RW_BARRIER))
req->cmd_flags |= REQ_SOFTBARRIER;
req->q->prepare_discard_fn(req->q, req);
- } else if (unlikely(bio_barrier(bio)))
+ } else if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER)))
req->cmd_flags |= REQ_HARDBARRIER;
- if (bio_sync(bio))
+ if (bio_rw_flagged(bio, BIO_RW_SYNCIO))
req->cmd_flags |= REQ_RW_SYNC;
- if (bio_rw_meta(bio))
+ if (bio_rw_flagged(bio, BIO_RW_META))
req->cmd_flags |= REQ_RW_META;
- if (bio_noidle(bio))
+ if (bio_rw_flagged(bio, BIO_RW_NOIDLE))
req->cmd_flags |= REQ_NOIDLE;
req->errors = 0;
@@ -1151,7 +1147,7 @@ void init_request_from_bio(struct request *req, struct bio *bio)
*/
static inline bool queue_should_plug(struct request_queue *q)
{
- return !(blk_queue_nonrot(q) && blk_queue_tagged(q));
+ return !(blk_queue_nonrot(q) && blk_queue_queuing(q));
}
static int __make_request(struct request_queue *q, struct bio *bio)
@@ -1160,11 +1156,12 @@ static int __make_request(struct request_queue *q, struct bio *bio)
int el_ret;
unsigned int bytes = bio->bi_size;
const unsigned short prio = bio_prio(bio);
- const int sync = bio_sync(bio);
- const int unplug = bio_unplug(bio);
+ const bool sync = bio_rw_flagged(bio, BIO_RW_SYNCIO);
+ const bool unplug = bio_rw_flagged(bio, BIO_RW_UNPLUG);
+ const unsigned int ff = bio->bi_rw & REQ_FAILFAST_MASK;
int rw_flags;
- if (bio_barrier(bio) && bio_has_data(bio) &&
+ if (bio_rw_flagged(bio, BIO_RW_BARRIER) && bio_has_data(bio) &&
(q->next_ordered == QUEUE_ORDERED_NONE)) {
bio_endio(bio, -EOPNOTSUPP);
return 0;
@@ -1178,7 +1175,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
spin_lock_irq(q->queue_lock);
- if (unlikely(bio_barrier(bio)) || elv_queue_empty(q))
+ if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER)) || elv_queue_empty(q))
goto get_rq;
el_ret = elv_merge(q, &req, bio);
@@ -1191,6 +1188,9 @@ static int __make_request(struct request_queue *q, struct bio *bio)
trace_block_bio_backmerge(q, bio);
+ if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
+ blk_rq_set_mixed_merge(req);
+
req->biotail->bi_next = bio;
req->biotail = bio;
req->__data_len += bytes;
@@ -1210,6 +1210,12 @@ static int __make_request(struct request_queue *q, struct bio *bio)
trace_block_bio_frontmerge(q, bio);
+ if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) {
+ blk_rq_set_mixed_merge(req);
+ req->cmd_flags &= ~REQ_FAILFAST_MASK;
+ req->cmd_flags |= ff;
+ }
+
bio->bi_next = req->bio;
req->bio = bio;
@@ -1457,19 +1463,20 @@ static inline void __generic_make_request(struct bio *bio)
if (old_sector != -1)
trace_block_remap(q, bio, old_dev, old_sector);
- trace_block_bio_queue(q, bio);
-
old_sector = bio->bi_sector;
old_dev = bio->bi_bdev->bd_dev;
if (bio_check_eod(bio, nr_sectors))
goto end_io;
- if (bio_discard(bio) && !q->prepare_discard_fn) {
+ if (bio_rw_flagged(bio, BIO_RW_DISCARD) &&
+ !q->prepare_discard_fn) {
err = -EOPNOTSUPP;
goto end_io;
}
+ trace_block_bio_queue(q, bio);
+
ret = q->make_request_fn(q, bio);
} while (ret);
@@ -1654,6 +1661,50 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
}
EXPORT_SYMBOL_GPL(blk_insert_cloned_request);
+/**
+ * blk_rq_err_bytes - determine number of bytes till the next failure boundary
+ * @rq: request to examine
+ *
+ * Description:
+ * A request could be merge of IOs which require different failure
+ * handling. This function determines the number of bytes which
+ * can be failed from the beginning of the request without
+ * crossing into area which need to be retried further.
+ *
+ * Return:
+ * The number of bytes to fail.
+ *
+ * Context:
+ * queue_lock must be held.
+ */
+unsigned int blk_rq_err_bytes(const struct request *rq)
+{
+ unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
+ unsigned int bytes = 0;
+ struct bio *bio;
+
+ if (!(rq->cmd_flags & REQ_MIXED_MERGE))
+ return blk_rq_bytes(rq);
+
+ /*
+ * Currently the only 'mixing' which can happen is between
+ * different fastfail types. We can safely fail portions
+ * which have all the failfast bits that the first one has -
+ * the ones which are at least as eager to fail as the first
+ * one.
+ */
+ for (bio = rq->bio; bio; bio = bio->bi_next) {
+ if ((bio->bi_rw & ff) != ff)
+ break;
+ bytes += bio->bi_size;
+ }
+
+ /* this could lead to infinite loop */
+ BUG_ON(blk_rq_bytes(rq) && !bytes);
+ return bytes;
+}
+EXPORT_SYMBOL_GPL(blk_rq_err_bytes);
+
static void blk_account_io_completion(struct request *req, unsigned int bytes)
{
if (blk_do_io_stat(req)) {
@@ -1687,7 +1738,7 @@ static void blk_account_io_done(struct request *req)
part_stat_inc(cpu, part, ios[rw]);
part_stat_add(cpu, part, ticks[rw], duration);
part_round_stats(cpu, part);
- part_dec_in_flight(part);
+ part_dec_in_flight(part, rw);
part_stat_unlock();
}
@@ -1807,8 +1858,15 @@ void blk_dequeue_request(struct request *rq)
* and to it is freed is accounted as io that is in progress at
* the driver side.
*/
- if (blk_account_rq(rq))
+ if (blk_account_rq(rq)) {
q->in_flight[rq_is_sync(rq)]++;
+ /*
+ * Mark this device as supporting hardware queuing, if
+ * we have more IOs in flight than 4.
+ */
+ if (!blk_queue_queuing(q) && queue_in_flight(q) > 4)
+ set_bit(QUEUE_FLAG_CQ, &q->queue_flags);
+ }
}
/**
@@ -2000,6 +2058,12 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes)
if (blk_fs_request(req) || blk_discard_rq(req))
req->__sector += total_bytes >> 9;
+ /* mixed attributes always follow the first bio */
+ if (req->cmd_flags & REQ_MIXED_MERGE) {
+ req->cmd_flags &= ~REQ_FAILFAST_MASK;
+ req->cmd_flags |= req->bio->bi_rw & REQ_FAILFAST_MASK;
+ }
+
/*
* If total number of sectors is less than the first segment
* size, something has gone terribly wrong.
@@ -2179,6 +2243,25 @@ bool blk_end_request_cur(struct request *rq, int error)
EXPORT_SYMBOL(blk_end_request_cur);
/**
+ * blk_end_request_err - Finish a request till the next failure boundary.
+ * @rq: the request to finish till the next failure boundary for
+ * @error: must be negative errno
+ *
+ * Description:
+ * Complete @rq till the next failure boundary.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool blk_end_request_err(struct request *rq, int error)
+{
+ WARN_ON(error >= 0);
+ return blk_end_request(rq, error, blk_rq_err_bytes(rq));
+}
+EXPORT_SYMBOL_GPL(blk_end_request_err);
+
+/**
* __blk_end_request - Helper function for drivers to complete the request.
* @rq: the request being processed
* @error: %0 for success, < %0 for error
@@ -2237,12 +2320,31 @@ bool __blk_end_request_cur(struct request *rq, int error)
}
EXPORT_SYMBOL(__blk_end_request_cur);
+/**
+ * __blk_end_request_err - Finish a request till the next failure boundary.
+ * @rq: the request to finish till the next failure boundary for
+ * @error: must be negative errno
+ *
+ * Description:
+ * Complete @rq till the next failure boundary. Must be called
+ * with queue lock held.
+ *
+ * Return:
+ * %false - we are done with this request
+ * %true - still buffers pending for this request
+ */
+bool __blk_end_request_err(struct request *rq, int error)
+{
+ WARN_ON(error >= 0);
+ return __blk_end_request(rq, error, blk_rq_err_bytes(rq));
+}
+EXPORT_SYMBOL_GPL(__blk_end_request_err);
+
void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
struct bio *bio)
{
- /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw, and
- we want BIO_RW_AHEAD (bit 1) to imply REQ_FAILFAST (bit 1). */
- rq->cmd_flags |= (bio->bi_rw & 3);
+ /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw */
+ rq->cmd_flags |= bio->bi_rw & REQ_RW;
if (bio_has_data(bio)) {
rq->nr_phys_segments = bio_phys_segments(q, bio);
diff --git a/block/blk-iopoll.c b/block/blk-iopoll.c
new file mode 100644
index 000000000000..ca564202ed7a
--- /dev/null
+++ b/block/blk-iopoll.c
@@ -0,0 +1,227 @@
+/*
+ * Functions related to interrupt-poll handling in the block layer. This
+ * is similar to NAPI for network devices.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/interrupt.h>
+#include <linux/cpu.h>
+#include <linux/blk-iopoll.h>
+#include <linux/delay.h>
+
+#include "blk.h"
+
+int blk_iopoll_enabled = 1;
+EXPORT_SYMBOL(blk_iopoll_enabled);
+
+static unsigned int blk_iopoll_budget __read_mostly = 256;
+
+static DEFINE_PER_CPU(struct list_head, blk_cpu_iopoll);
+
+/**
+ * blk_iopoll_sched - Schedule a run of the iopoll handler
+ * @iop: The parent iopoll structure
+ *
+ * Description:
+ * Add this blk_iopoll structure to the pending poll list and trigger the
+ * raise of the blk iopoll softirq. The driver must already have gotten a
+ * succesful return from blk_iopoll_sched_prep() before calling this.
+ **/
+void blk_iopoll_sched(struct blk_iopoll *iop)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ list_add_tail(&iop->list, &__get_cpu_var(blk_cpu_iopoll));
+ __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(blk_iopoll_sched);
+
+/**
+ * __blk_iopoll_complete - Mark this @iop as un-polled again
+ * @iop: The parent iopoll structure
+ *
+ * Description:
+ * See blk_iopoll_complete(). This function must be called with interrupts
+ * disabled.
+ **/
+void __blk_iopoll_complete(struct blk_iopoll *iop)
+{
+ list_del(&iop->list);
+ smp_mb__before_clear_bit();
+ clear_bit_unlock(IOPOLL_F_SCHED, &iop->state);
+}
+EXPORT_SYMBOL(__blk_iopoll_complete);
+
+/**
+ * blk_iopoll_complete - Mark this @iop as un-polled again
+ * @iop: The parent iopoll structure
+ *
+ * Description:
+ * If a driver consumes less than the assigned budget in its run of the
+ * iopoll handler, it'll end the polled mode by calling this function. The
+ * iopoll handler will not be invoked again before blk_iopoll_sched_prep()
+ * is called.
+ **/
+void blk_iopoll_complete(struct blk_iopoll *iopoll)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ __blk_iopoll_complete(iopoll);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(blk_iopoll_complete);
+
+static void blk_iopoll_softirq(struct softirq_action *h)
+{
+ struct list_head *list = &__get_cpu_var(blk_cpu_iopoll);
+ int rearm = 0, budget = blk_iopoll_budget;
+ unsigned long start_time = jiffies;
+
+ local_irq_disable();
+
+ while (!list_empty(list)) {
+ struct blk_iopoll *iop;
+ int work, weight;
+
+ /*
+ * If softirq window is exhausted then punt.
+ */
+ if (budget <= 0 || time_after(jiffies, start_time)) {
+ rearm = 1;
+ break;
+ }
+
+ local_irq_enable();
+
+ /* Even though interrupts have been re-enabled, this
+ * access is safe because interrupts can only add new
+ * entries to the tail of this list, and only ->poll()
+ * calls can remove this head entry from the list.
+ */
+ iop = list_entry(list->next, struct blk_iopoll, list);
+
+ weight = iop->weight;
+ work = 0;
+ if (test_bit(IOPOLL_F_SCHED, &iop->state))
+ work = iop->poll(iop, weight);
+
+ budget -= work;
+
+ local_irq_disable();
+
+ /*
+ * Drivers must not modify the iopoll state, if they
+ * consume their assigned weight (or more, some drivers can't
+ * easily just stop processing, they have to complete an
+ * entire mask of commands).In such cases this code
+ * still "owns" the iopoll instance and therefore can
+ * move the instance around on the list at-will.
+ */
+ if (work >= weight) {
+ if (blk_iopoll_disable_pending(iop))
+ __blk_iopoll_complete(iop);
+ else
+ list_move_tail(&iop->list, list);
+ }
+ }
+
+ if (rearm)
+ __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ);
+
+ local_irq_enable();
+}
+
+/**
+ * blk_iopoll_disable - Disable iopoll on this @iop
+ * @iop: The parent iopoll structure
+ *
+ * Description:
+ * Disable io polling and wait for any pending callbacks to have completed.
+ **/
+void blk_iopoll_disable(struct blk_iopoll *iop)
+{
+ set_bit(IOPOLL_F_DISABLE, &iop->state);
+ while (test_and_set_bit(IOPOLL_F_SCHED, &iop->state))
+ msleep(1);
+ clear_bit(IOPOLL_F_DISABLE, &iop->state);
+}
+EXPORT_SYMBOL(blk_iopoll_disable);
+
+/**
+ * blk_iopoll_enable - Enable iopoll on this @iop
+ * @iop: The parent iopoll structure
+ *
+ * Description:
+ * Enable iopoll on this @iop. Note that the handler run will not be
+ * scheduled, it will only mark it as active.
+ **/
+void blk_iopoll_enable(struct blk_iopoll *iop)
+{
+ BUG_ON(!test_bit(IOPOLL_F_SCHED, &iop->state));
+ smp_mb__before_clear_bit();
+ clear_bit_unlock(IOPOLL_F_SCHED, &iop->state);
+}
+EXPORT_SYMBOL(blk_iopoll_enable);
+
+/**
+ * blk_iopoll_init - Initialize this @iop
+ * @iop: The parent iopoll structure
+ * @weight: The default weight (or command completion budget)
+ * @poll_fn: The handler to invoke
+ *
+ * Description:
+ * Initialize this blk_iopoll structure. Before being actively used, the
+ * driver must call blk_iopoll_enable().
+ **/
+void blk_iopoll_init(struct blk_iopoll *iop, int weight, blk_iopoll_fn *poll_fn)
+{
+ memset(iop, 0, sizeof(*iop));
+ INIT_LIST_HEAD(&iop->list);
+ iop->weight = weight;
+ iop->poll = poll_fn;
+ set_bit(IOPOLL_F_SCHED, &iop->state);
+}
+EXPORT_SYMBOL(blk_iopoll_init);
+
+static int __cpuinit blk_iopoll_cpu_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ /*
+ * If a CPU goes away, splice its entries to the current CPU
+ * and trigger a run of the softirq
+ */
+ if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
+ int cpu = (unsigned long) hcpu;
+
+ local_irq_disable();
+ list_splice_init(&per_cpu(blk_cpu_iopoll, cpu),
+ &__get_cpu_var(blk_cpu_iopoll));
+ __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ);
+ local_irq_enable();
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata blk_iopoll_cpu_notifier = {
+ .notifier_call = blk_iopoll_cpu_notify,
+};
+
+static __init int blk_iopoll_setup(void)
+{
+ int i;
+
+ for_each_possible_cpu(i)
+ INIT_LIST_HEAD(&per_cpu(blk_cpu_iopoll, i));
+
+ open_softirq(BLOCK_IOPOLL_SOFTIRQ, blk_iopoll_softirq);
+ register_hotcpu_notifier(&blk_iopoll_cpu_notifier);
+ return 0;
+}
+subsys_initcall(blk_iopoll_setup);
diff --git a/block/blk-merge.c b/block/blk-merge.c
index e1999679a4d5..99cb5cf1f447 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -311,6 +311,36 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
return 1;
}
+/**
+ * blk_rq_set_mixed_merge - mark a request as mixed merge
+ * @rq: request to mark as mixed merge
+ *
+ * Description:
+ * @rq is about to be mixed merged. Make sure the attributes
+ * which can be mixed are set in each bio and mark @rq as mixed
+ * merged.
+ */
+void blk_rq_set_mixed_merge(struct request *rq)
+{
+ unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK;
+ struct bio *bio;
+
+ if (rq->cmd_flags & REQ_MIXED_MERGE)
+ return;
+
+ /*
+ * @rq will no longer represent mixable attributes for all the
+ * contained bios. It will just track those of the first one.
+ * Distributes the attributs to each bio.
+ */
+ for (bio = rq->bio; bio; bio = bio->bi_next) {
+ WARN_ON_ONCE((bio->bi_rw & REQ_FAILFAST_MASK) &&
+ (bio->bi_rw & REQ_FAILFAST_MASK) != ff);
+ bio->bi_rw |= ff;
+ }
+ rq->cmd_flags |= REQ_MIXED_MERGE;
+}
+
static void blk_account_io_merge(struct request *req)
{
if (blk_do_io_stat(req)) {
@@ -321,7 +351,7 @@ static void blk_account_io_merge(struct request *req)
part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
part_round_stats(cpu, part);
- part_dec_in_flight(part);
+ part_dec_in_flight(part, rq_data_dir(req));
part_stat_unlock();
}
@@ -350,12 +380,6 @@ static int attempt_merge(struct request_queue *q, struct request *req,
if (blk_integrity_rq(req) != blk_integrity_rq(next))
return 0;
- /* don't merge requests of different failfast settings */
- if (blk_failfast_dev(req) != blk_failfast_dev(next) ||
- blk_failfast_transport(req) != blk_failfast_transport(next) ||
- blk_failfast_driver(req) != blk_failfast_driver(next))
- return 0;
-
/*
* If we are allowed to merge, then append bio list
* from next to rq and release next. merge_requests_fn
@@ -366,6 +390,19 @@ static int attempt_merge(struct request_queue *q, struct request *req,
return 0;
/*
+ * If failfast settings disagree or any of the two is already
+ * a mixed merge, mark both as mixed before proceeding. This
+ * makes sure that all involved bios have mixable attributes
+ * set properly.
+ */
+ if ((req->cmd_flags | next->cmd_flags) & REQ_MIXED_MERGE ||
+ (req->cmd_flags & REQ_FAILFAST_MASK) !=
+ (next->cmd_flags & REQ_FAILFAST_MASK)) {
+ blk_rq_set_mixed_merge(req);
+ blk_rq_set_mixed_merge(next);
+ }
+
+ /*
* At this point we have either done a back merge
* or front merge. We need the smaller start_time of
* the merged requests to be the current request
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 476d87065073..83413ff83739 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -428,6 +428,25 @@ void blk_queue_io_min(struct request_queue *q, unsigned int min)
EXPORT_SYMBOL(blk_queue_io_min);
/**
+ * blk_limits_io_opt - set optimal request size for a device
+ * @limits: the queue limits
+ * @opt: smallest I/O size in bytes
+ *
+ * Description:
+ * Storage devices may report an optimal I/O size, which is the
+ * device's preferred unit for sustained I/O. This is rarely reported
+ * for disk drives. For RAID arrays it is usually the stripe width or
+ * the internal track size. A properly aligned multiple of
+ * optimal_io_size is the preferred request size for workloads where
+ * sustained throughput is desired.
+ */
+void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt)
+{
+ limits->io_opt = opt;
+}
+EXPORT_SYMBOL(blk_limits_io_opt);
+
+/**
* blk_queue_io_opt - set optimal request size for the queue
* @q: the request queue for the device
* @opt: optimal request size in bytes
@@ -442,7 +461,7 @@ EXPORT_SYMBOL(blk_queue_io_min);
*/
void blk_queue_io_opt(struct request_queue *q, unsigned int opt)
{
- q->limits.io_opt = opt;
+ blk_limits_io_opt(&q->limits, opt);
}
EXPORT_SYMBOL(blk_queue_io_opt);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index d3aa2aadb3e0..b78c9c3e2670 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -40,7 +40,12 @@ queue_requests_store(struct request_queue *q, const char *page, size_t count)
{
struct request_list *rl = &q->rq;
unsigned long nr;
- int ret = queue_var_store(&nr, page, count);
+ int ret;
+
+ if (!q->request_fn)
+ return -EINVAL;
+
+ ret = queue_var_store(&nr, page, count);
if (nr < BLKDEV_MIN_RQ)
nr = BLKDEV_MIN_RQ;
diff --git a/block/blk.h b/block/blk.h
index 3fae6add5430..5ee3d7e72feb 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -104,6 +104,7 @@ int ll_front_merge_fn(struct request_queue *q, struct request *req,
int attempt_back_merge(struct request_queue *q, struct request *rq);
int attempt_front_merge(struct request_queue *q, struct request *rq);
void blk_recalc_rq_segments(struct request *rq);
+void blk_rq_set_mixed_merge(struct request *rq);
void blk_queue_congestion_threshold(struct request_queue *q);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index fd7080ed7935..0e3814b662af 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -134,13 +134,8 @@ struct cfq_data {
struct rb_root prio_trees[CFQ_PRIO_LISTS];
unsigned int busy_queues;
- /*
- * Used to track any pending rt requests so we can pre-empt current
- * non-RT cfqq in service when this value is non-zero.
- */
- unsigned int busy_rt_queues;
- int rq_in_driver;
+ int rq_in_driver[2];
int sync_flight;
/*
@@ -191,7 +186,6 @@ enum cfqq_state_flags {
CFQ_CFQQ_FLAG_on_rr = 0, /* on round-robin busy list */
CFQ_CFQQ_FLAG_wait_request, /* waiting for a request */
CFQ_CFQQ_FLAG_must_dispatch, /* must be allowed a dispatch */
- CFQ_CFQQ_FLAG_must_alloc, /* must be allowed rq alloc */
CFQ_CFQQ_FLAG_must_alloc_slice, /* per-slice must_alloc flag */
CFQ_CFQQ_FLAG_fifo_expire, /* FIFO checked in this slice */
CFQ_CFQQ_FLAG_idle_window, /* slice idling enabled */
@@ -218,7 +212,6 @@ static inline int cfq_cfqq_##name(const struct cfq_queue *cfqq) \
CFQ_CFQQ_FNS(on_rr);
CFQ_CFQQ_FNS(wait_request);
CFQ_CFQQ_FNS(must_dispatch);
-CFQ_CFQQ_FNS(must_alloc);
CFQ_CFQQ_FNS(must_alloc_slice);
CFQ_CFQQ_FNS(fifo_expire);
CFQ_CFQQ_FNS(idle_window);
@@ -239,6 +232,11 @@ static struct cfq_queue *cfq_get_queue(struct cfq_data *, int,
static struct cfq_io_context *cfq_cic_lookup(struct cfq_data *,
struct io_context *);
+static inline int rq_in_driver(struct cfq_data *cfqd)
+{
+ return cfqd->rq_in_driver[0] + cfqd->rq_in_driver[1];
+}
+
static inline struct cfq_queue *cic_to_cfqq(struct cfq_io_context *cic,
int is_sync)
{
@@ -257,7 +255,7 @@ static inline void cic_set_cfqq(struct cfq_io_context *cic,
*/
static inline int cfq_bio_sync(struct bio *bio)
{
- if (bio_data_dir(bio) == READ || bio_sync(bio))
+ if (bio_data_dir(bio) == READ || bio_rw_flagged(bio, BIO_RW_SYNCIO))
return 1;
return 0;
@@ -648,8 +646,6 @@ static void cfq_add_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
BUG_ON(cfq_cfqq_on_rr(cfqq));
cfq_mark_cfqq_on_rr(cfqq);
cfqd->busy_queues++;
- if (cfq_class_rt(cfqq))
- cfqd->busy_rt_queues++;
cfq_resort_rr_list(cfqd, cfqq);
}
@@ -673,8 +669,6 @@ static void cfq_del_cfqq_rr(struct cfq_data *cfqd, struct cfq_queue *cfqq)
BUG_ON(!cfqd->busy_queues);
cfqd->busy_queues--;
- if (cfq_class_rt(cfqq))
- cfqd->busy_rt_queues--;
}
/*
@@ -760,9 +754,9 @@ static void cfq_activate_request(struct request_queue *q, struct request *rq)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
- cfqd->rq_in_driver++;
+ cfqd->rq_in_driver[rq_is_sync(rq)]++;
cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "activate rq, drv=%d",
- cfqd->rq_in_driver);
+ rq_in_driver(cfqd));
cfqd->last_position = blk_rq_pos(rq) + blk_rq_sectors(rq);
}
@@ -770,11 +764,12 @@ static void cfq_activate_request(struct request_queue *q, struct request *rq)
static void cfq_deactivate_request(struct request_queue *q, struct request *rq)
{
struct cfq_data *cfqd = q->elevator->elevator_data;
+ const int sync = rq_is_sync(rq);
- WARN_ON(!cfqd->rq_in_driver);
- cfqd->rq_in_driver--;
+ WARN_ON(!cfqd->rq_in_driver[sync]);
+ cfqd->rq_in_driver[sync]--;
cfq_log_cfqq(cfqd, RQ_CFQQ(rq), "deactivate rq, drv=%d",
- cfqd->rq_in_driver);
+ rq_in_driver(cfqd));
}
static void cfq_remove_request(struct request *rq)
@@ -1080,7 +1075,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
/*
* still requests with the driver, don't idle
*/
- if (cfqd->rq_in_driver)
+ if (rq_in_driver(cfqd))
return;
/*
@@ -1115,6 +1110,7 @@ static void cfq_dispatch_insert(struct request_queue *q, struct request *rq)
cfq_log_cfqq(cfqd, cfqq, "dispatch_insert");
+ cfqq->next_rq = cfq_find_next_rq(cfqd, cfqq, rq);
cfq_remove_request(rq);
cfqq->dispatched++;
elv_dispatch_sort(q, rq);
@@ -1179,20 +1175,6 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd)
goto expire;
/*
- * If we have a RT cfqq waiting, then we pre-empt the current non-rt
- * cfqq.
- */
- if (!cfq_class_rt(cfqq) && cfqd->busy_rt_queues) {
- /*
- * We simulate this as cfqq timed out so that it gets to bank
- * the remaining of its time slice.
- */
- cfq_log_cfqq(cfqd, cfqq, "preempt");
- cfq_slice_expired(cfqd, 1);
- goto new_queue;
- }
-
- /*
* The active queue has requests and isn't expired, allow it to
* dispatch.
*/
@@ -1312,6 +1294,12 @@ static int cfq_dispatch_requests(struct request_queue *q, int force)
return 0;
/*
+ * Drain async requests before we start sync IO
+ */
+ if (cfq_cfqq_idle_window(cfqq) && cfqd->rq_in_driver[BLK_RW_ASYNC])
+ return 0;
+
+ /*
* If this is an async queue and we have sync IO in flight, let it wait
*/
if (cfqd->sync_flight && !cfq_cfqq_sync(cfqq))
@@ -1362,7 +1350,7 @@ static int cfq_dispatch_requests(struct request_queue *q, int force)
cfq_slice_expired(cfqd, 0);
}
- cfq_log(cfqd, "dispatched a request");
+ cfq_log_cfqq(cfqd, cfqq, "dispatched a request");
return 1;
}
@@ -2130,11 +2118,11 @@ static void cfq_insert_request(struct request_queue *q, struct request *rq)
*/
static void cfq_update_hw_tag(struct cfq_data *cfqd)
{
- if (cfqd->rq_in_driver > cfqd->rq_in_driver_peak)
- cfqd->rq_in_driver_peak = cfqd->rq_in_driver;
+ if (rq_in_driver(cfqd) > cfqd->rq_in_driver_peak)
+ cfqd->rq_in_driver_peak = rq_in_driver(cfqd);
if (cfqd->rq_queued <= CFQ_HW_QUEUE_MIN &&
- cfqd->rq_in_driver <= CFQ_HW_QUEUE_MIN)
+ rq_in_driver(cfqd) <= CFQ_HW_QUEUE_MIN)
return;
if (cfqd->hw_tag_samples++ < 50)
@@ -2161,9 +2149,9 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
cfq_update_hw_tag(cfqd);
- WARN_ON(!cfqd->rq_in_driver);
+ WARN_ON(!cfqd->rq_in_driver[sync]);
WARN_ON(!cfqq->dispatched);
- cfqd->rq_in_driver--;
+ cfqd->rq_in_driver[sync]--;
cfqq->dispatched--;
if (cfq_cfqq_sync(cfqq))
@@ -2197,7 +2185,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
cfq_arm_slice_timer(cfqd);
}
- if (!cfqd->rq_in_driver)
+ if (!rq_in_driver(cfqd))
cfq_schedule_dispatch(cfqd);
}
@@ -2229,8 +2217,7 @@ static void cfq_prio_boost(struct cfq_queue *cfqq)
static inline int __cfq_may_queue(struct cfq_queue *cfqq)
{
- if ((cfq_cfqq_wait_request(cfqq) || cfq_cfqq_must_alloc(cfqq)) &&
- !cfq_cfqq_must_alloc_slice(cfqq)) {
+ if (cfq_cfqq_wait_request(cfqq) && !cfq_cfqq_must_alloc_slice(cfqq)) {
cfq_mark_cfqq_must_alloc_slice(cfqq);
return ELV_MQUEUE_MUST;
}
@@ -2317,7 +2304,6 @@ cfq_set_request(struct request_queue *q, struct request *rq, gfp_t gfp_mask)
}
cfqq->allocated[rw]++;
- cfq_clear_cfqq_must_alloc(cfqq);
atomic_inc(&cfqq->ref);
spin_unlock_irqrestore(q->queue_lock, flags);
diff --git a/block/elevator.c b/block/elevator.c
index 2d511f9105e1..1975b619c86d 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -79,7 +79,8 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio)
/*
* Don't merge file system requests and discard requests
*/
- if (bio_discard(bio) != bio_discard(rq->bio))
+ if (bio_rw_flagged(bio, BIO_RW_DISCARD) !=
+ bio_rw_flagged(rq->bio, BIO_RW_DISCARD))
return 0;
/*
@@ -100,19 +101,6 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio)
if (bio_integrity(bio) != blk_integrity_rq(rq))
return 0;
- /*
- * Don't merge if failfast settings don't match.
- *
- * FIXME: The negation in front of each condition is necessary
- * because bio and request flags use different bit positions
- * and the accessors return those bits directly. This
- * ugliness will soon go away.
- */
- if (!bio_failfast_dev(bio) != !blk_failfast_dev(rq) ||
- !bio_failfast_transport(bio) != !blk_failfast_transport(rq) ||
- !bio_failfast_driver(bio) != !blk_failfast_driver(rq))
- return 0;
-
if (!elv_iosched_allow_merge(rq, bio))
return 0;
diff --git a/block/genhd.c b/block/genhd.c
index f4c64c2b303a..5b76bf55d05c 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -869,6 +869,7 @@ static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
+static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
#ifdef CONFIG_FAIL_MAKE_REQUEST
static struct device_attribute dev_attr_fail =
__ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
@@ -888,6 +889,7 @@ static struct attribute *disk_attrs[] = {
&dev_attr_alignment_offset.attr,
&dev_attr_capability.attr,
&dev_attr_stat.attr,
+ &dev_attr_inflight.attr,
#ifdef CONFIG_FAIL_MAKE_REQUEST
&dev_attr_fail.attr,
#endif
@@ -1053,7 +1055,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
part_stat_read(hd, merges[1]),
(unsigned long long)part_stat_read(hd, sectors[1]),
jiffies_to_msecs(part_stat_read(hd, ticks[1])),
- hd->in_flight,
+ part_in_flight(hd),
jiffies_to_msecs(part_stat_read(hd, io_ticks)),
jiffies_to_msecs(part_stat_read(hd, time_in_queue))
);
@@ -1215,6 +1217,16 @@ void put_disk(struct gendisk *disk)
EXPORT_SYMBOL(put_disk);
+static void set_disk_ro_uevent(struct gendisk *gd, int ro)
+{
+ char event[] = "DISK_RO=1";
+ char *envp[] = { event, NULL };
+
+ if (!ro)
+ event[8] = '0';
+ kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
+}
+
void set_device_ro(struct block_device *bdev, int flag)
{
bdev->bd_part->policy = flag;
@@ -1227,8 +1239,12 @@ void set_disk_ro(struct gendisk *disk, int flag)
struct disk_part_iter piter;
struct hd_struct *part;
- disk_part_iter_init(&piter, disk,
- DISK_PITER_INCL_EMPTY | DISK_PITER_INCL_PART0);
+ if (disk->part0.policy != flag) {
+ set_disk_ro_uevent(disk, flag);
+ disk->part0.policy = flag;
+ }
+
+ disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
while ((part = disk_part_iter_next(&piter)))
part->policy = flag;
disk_part_iter_exit(&piter);
diff --git a/block/ioctl.c b/block/ioctl.c
index 500e4c73cc52..d3e6b5827a34 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -112,22 +112,9 @@ static int blkdev_reread_part(struct block_device *bdev)
return res;
}
-static void blk_ioc_discard_endio(struct bio *bio, int err)
-{
- if (err) {
- if (err == -EOPNOTSUPP)
- set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
- clear_bit(BIO_UPTODATE, &bio->bi_flags);
- }
- complete(bio->bi_private);
-}
-
static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
uint64_t len)
{
- struct request_queue *q = bdev_get_queue(bdev);
- int ret = 0;
-
if (start & 511)
return -EINVAL;
if (len & 511)
@@ -137,40 +124,8 @@ static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
if (start + len > (bdev->bd_inode->i_size >> 9))
return -EINVAL;
-
- if (!q->prepare_discard_fn)
- return -EOPNOTSUPP;
-
- while (len && !ret) {
- DECLARE_COMPLETION_ONSTACK(wait);
- struct bio *bio;
-
- bio = bio_alloc(GFP_KERNEL, 0);
-
- bio->bi_end_io = blk_ioc_discard_endio;
- bio->bi_bdev = bdev;
- bio->bi_private = &wait;
- bio->bi_sector = start;
-
- if (len > queue_max_hw_sectors(q)) {
- bio->bi_size = queue_max_hw_sectors(q) << 9;
- len -= queue_max_hw_sectors(q);
- start += queue_max_hw_sectors(q);
- } else {
- bio->bi_size = len << 9;
- len = 0;
- }
- submit_bio(DISCARD_NOBARRIER, bio);
-
- wait_for_completion(&wait);
-
- if (bio_flagged(bio, BIO_EOPNOTSUPP))
- ret = -EOPNOTSUPP;
- else if (!bio_flagged(bio, BIO_UPTODATE))
- ret = -EIO;
- bio_put(bio);
- }
- return ret;
+ return blkdev_issue_discard(bdev, start, len, GFP_KERNEL,
+ DISCARD_FL_WAIT);
}
static int put_ushort(unsigned long arg, unsigned short val)