Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block layer fixes from Jens Axboe:
"Four small fixes that should be merged for the current 3.18-rc series.
This pull request contains:
- a minor bugfix for computation of best IO priority given two
merging requests. From Jan Kara.
- the final (final) merge count issue that has been plaguing
virtio-blk. From Ming Lei.
- enable parallel reinit notify for blk-mq queues, to combine the
cost of an RCU grace period across lots of devices. From Tejun
Heo.
- an error handling fix for the SCSI_IOCTL_SEND_COMMAND ioctl. From
Tony Battersby"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: blk-merge: fix blk_recount_segments()
scsi: Fix more error handling in SCSI_IOCTL_SEND_COMMAND
blk-mq: make mq_queue_reinit_notify() freeze queues in parallel
block: Fix computation of merged request priority
diff --git a/block/blk-merge.c b/block/blk-merge.c
index b3ac40a..89b97b5 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -97,19 +97,22 @@
void blk_recount_segments(struct request_queue *q, struct bio *bio)
{
- bool no_sg_merge = !!test_bit(QUEUE_FLAG_NO_SG_MERGE,
- &q->queue_flags);
- bool merge_not_need = bio->bi_vcnt < queue_max_segments(q);
+ unsigned short seg_cnt;
- if (no_sg_merge && !bio_flagged(bio, BIO_CLONED) &&
- merge_not_need)
- bio->bi_phys_segments = bio->bi_vcnt;
+ /* estimate segment number by bi_vcnt for non-cloned bio */
+ if (bio_flagged(bio, BIO_CLONED))
+ seg_cnt = bio_segments(bio);
+ else
+ seg_cnt = bio->bi_vcnt;
+
+ if (test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags) &&
+ (seg_cnt < queue_max_segments(q)))
+ bio->bi_phys_segments = seg_cnt;
else {
struct bio *nxt = bio->bi_next;
bio->bi_next = NULL;
- bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio,
- no_sg_merge && merge_not_need);
+ bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio, false);
bio->bi_next = nxt;
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 68929ba..1d016fc 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -107,11 +107,7 @@
wake_up_all(&q->mq_freeze_wq);
}
-/*
- * Guarantee no request is in use, so we can change any data structure of
- * the queue afterward.
- */
-void blk_mq_freeze_queue(struct request_queue *q)
+static void blk_mq_freeze_queue_start(struct request_queue *q)
{
bool freeze;
@@ -123,9 +119,23 @@
percpu_ref_kill(&q->mq_usage_counter);
blk_mq_run_queues(q, false);
}
+}
+
+static void blk_mq_freeze_queue_wait(struct request_queue *q)
+{
wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter));
}
+/*
+ * Guarantee no request is in use, so we can change any data structure of
+ * the queue afterward.
+ */
+void blk_mq_freeze_queue(struct request_queue *q)
+{
+ blk_mq_freeze_queue_start(q);
+ blk_mq_freeze_queue_wait(q);
+}
+
static void blk_mq_unfreeze_queue(struct request_queue *q)
{
bool wake;
@@ -1921,7 +1931,7 @@
/* Basically redo blk_mq_init_queue with queue frozen */
static void blk_mq_queue_reinit(struct request_queue *q)
{
- blk_mq_freeze_queue(q);
+ WARN_ON_ONCE(!q->mq_freeze_depth);
blk_mq_sysfs_unregister(q);
@@ -1936,8 +1946,6 @@
blk_mq_map_swqueue(q);
blk_mq_sysfs_register(q);
-
- blk_mq_unfreeze_queue(q);
}
static int blk_mq_queue_reinit_notify(struct notifier_block *nb,
@@ -1956,8 +1964,25 @@
return NOTIFY_OK;
mutex_lock(&all_q_mutex);
+
+ /*
+ * We need to freeze and reinit all existing queues. Freezing
+ * involves synchronous wait for an RCU grace period and doing it
+ * one by one may take a long time. Start freezing all queues in
+ * one swoop and then wait for the completions so that freezing can
+ * take place in parallel.
+ */
+ list_for_each_entry(q, &all_q_list, all_q_node)
+ blk_mq_freeze_queue_start(q);
+ list_for_each_entry(q, &all_q_list, all_q_node)
+ blk_mq_freeze_queue_wait(q);
+
list_for_each_entry(q, &all_q_list, all_q_node)
blk_mq_queue_reinit(q);
+
+ list_for_each_entry(q, &all_q_list, all_q_node)
+ blk_mq_unfreeze_queue(q);
+
mutex_unlock(&all_q_mutex);
return NOTIFY_OK;
}
diff --git a/block/ioprio.c b/block/ioprio.c
index e50170c..31666c9 100644
--- a/block/ioprio.c
+++ b/block/ioprio.c
@@ -157,14 +157,16 @@
int ioprio_best(unsigned short aprio, unsigned short bprio)
{
- unsigned short aclass = IOPRIO_PRIO_CLASS(aprio);
- unsigned short bclass = IOPRIO_PRIO_CLASS(bprio);
+ unsigned short aclass;
+ unsigned short bclass;
- if (aclass == IOPRIO_CLASS_NONE)
- aclass = IOPRIO_CLASS_BE;
- if (bclass == IOPRIO_CLASS_NONE)
- bclass = IOPRIO_CLASS_BE;
+ if (!ioprio_valid(aprio))
+ aprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
+ if (!ioprio_valid(bprio))
+ bprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
+ aclass = IOPRIO_PRIO_CLASS(aprio);
+ bclass = IOPRIO_PRIO_CLASS(bprio);
if (aclass == bclass)
return min(aprio, bprio);
if (aclass > bclass)
diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
index 1e053d9..b0c2a61 100644
--- a/block/scsi_ioctl.c
+++ b/block/scsi_ioctl.c
@@ -458,7 +458,7 @@
rq = blk_get_request(q, in_len ? WRITE : READ, __GFP_WAIT);
if (IS_ERR(rq)) {
err = PTR_ERR(rq);
- goto error;
+ goto error_free_buffer;
}
blk_rq_set_block_pc(rq);
@@ -531,9 +531,11 @@
}
error:
+ blk_put_request(rq);
+
+error_free_buffer:
kfree(buffer);
- if (rq)
- blk_put_request(rq);
+
return err;
}
EXPORT_SYMBOL_GPL(sg_scsi_ioctl);