summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2019-04-20 12:20:58 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-04-20 12:20:58 -0700
commit38a2ca2cac28cd202a364e30f9fd252ac66619be (patch)
treeadeccbd11f5f62a3ddf473075ad04bac27d9cf26
parent34396bdfd2b7b41b9dcd2126eb1a57e43fe13368 (diff)
parent6bedf00e55e5dd0a4ed1ad3f06131edd6fb56ec8 (diff)
downloadlinux-sh-38a2ca2cac28cd202a364e30f9fd252ac66619be.tar.gz
Merge tag 'for-linus-20190420' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe: "A set of small fixes that should go into this series. This contains: - Removal of unused queue member (Hou) - Overflow bvec fix (Ming) - Various little io_uring tweaks (me) - kthread parking - Only call cpu_possible() for verified CPU - Drop unused 'file' argument to io_file_put() - io_uring_enter vs io_uring_register deadlock fix - CQ overflow fix - BFQ internal depth update fix (me)" * tag 'for-linus-20190420' of git://git.kernel.dk/linux-block: block: make sure that bvec length can't be overflow block: kill all_q_node in request_queue io_uring: fix CQ overflow condition io_uring: fix possible deadlock between io_uring_{enter,register} io_uring: drop io_file_put() 'file' argument bfq: update internal depth state when queue depth changes io_uring: only test SQPOLL cpu after we've verified it io_uring: park SQPOLL thread if it's percpu
-rw-r--r--block/bfq-iosched.c8
-rw-r--r--block/blk-mq.c2
-rw-r--r--fs/io_uring.c41
-rw-r--r--include/linux/blkdev.h1
-rw-r--r--include/linux/bvec.h5
-rw-r--r--include/linux/elevator.h1
6 files changed, 43 insertions, 15 deletions
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index dfb8cb0af13a..5ba1e0d841b4 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -5396,7 +5396,7 @@ static unsigned int bfq_update_depths(struct bfq_data *bfqd,
return min_shallow;
}
-static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
+static void bfq_depth_updated(struct blk_mq_hw_ctx *hctx)
{
struct bfq_data *bfqd = hctx->queue->elevator->elevator_data;
struct blk_mq_tags *tags = hctx->sched_tags;
@@ -5404,6 +5404,11 @@ static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
min_shallow = bfq_update_depths(bfqd, &tags->bitmap_tags);
sbitmap_queue_min_shallow_depth(&tags->bitmap_tags, min_shallow);
+}
+
+static int bfq_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int index)
+{
+ bfq_depth_updated(hctx);
return 0;
}
@@ -5826,6 +5831,7 @@ static struct elevator_type iosched_bfq_mq = {
.requests_merged = bfq_requests_merged,
.request_merged = bfq_request_merged,
.has_work = bfq_has_work,
+ .depth_updated = bfq_depth_updated,
.init_hctx = bfq_init_hctx,
.init_sched = bfq_init_queue,
.exit_sched = bfq_exit_queue,
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 9516304a38ee..fc60ed7e940e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -3135,6 +3135,8 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
}
if (ret)
break;
+ if (q->elevator && q->elevator->type->ops.depth_updated)
+ q->elevator->type->ops.depth_updated(hctx);
}
if (!ret)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 89aa8412b5f5..f65f85d89217 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -338,7 +338,7 @@ static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx)
tail = ctx->cached_cq_tail;
/* See comment at the top of the file */
smp_rmb();
- if (tail + 1 == READ_ONCE(ring->r.head))
+ if (tail - READ_ONCE(ring->r.head) == ring->ring_entries)
return NULL;
ctx->cached_cq_tail++;
@@ -682,11 +682,9 @@ static void io_iopoll_req_issued(struct io_kiocb *req)
list_add_tail(&req->list, &ctx->poll_list);
}
-static void io_file_put(struct io_submit_state *state, struct file *file)
+static void io_file_put(struct io_submit_state *state)
{
- if (!state) {
- fput(file);
- } else if (state->file) {
+ if (state->file) {
int diff = state->has_refs - state->used_refs;
if (diff)
@@ -711,7 +709,7 @@ static struct file *io_file_get(struct io_submit_state *state, int fd)
state->ios_left--;
return state->file;
}
- io_file_put(state, NULL);
+ io_file_put(state);
}
state->file = fget_many(fd, state->ios_left);
if (!state->file)
@@ -1671,7 +1669,7 @@ out:
static void io_submit_state_end(struct io_submit_state *state)
{
blk_finish_plug(&state->plug);
- io_file_put(state, NULL);
+ io_file_put(state);
if (state->free_reqs)
kmem_cache_free_bulk(req_cachep, state->free_reqs,
&state->reqs[state->cur_req]);
@@ -1920,6 +1918,10 @@ static int io_sq_thread(void *data)
unuse_mm(cur_mm);
mmput(cur_mm);
}
+
+ if (kthread_should_park())
+ kthread_parkme();
+
return 0;
}
@@ -2054,6 +2056,7 @@ static void io_sq_thread_stop(struct io_ring_ctx *ctx)
if (ctx->sqo_thread) {
ctx->sqo_stop = 1;
mb();
+ kthread_park(ctx->sqo_thread);
kthread_stop(ctx->sqo_thread);
ctx->sqo_thread = NULL;
}
@@ -2236,10 +2239,6 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx,
mmgrab(current->mm);
ctx->sqo_mm = current->mm;
- ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
- if (!ctx->sq_thread_idle)
- ctx->sq_thread_idle = HZ;
-
ret = -EINVAL;
if (!cpu_possible(p->sq_thread_cpu))
goto err;
@@ -2249,10 +2248,18 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx,
if (!capable(CAP_SYS_ADMIN))
goto err;
+ ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
+ if (!ctx->sq_thread_idle)
+ ctx->sq_thread_idle = HZ;
+
if (p->flags & IORING_SETUP_SQ_AFF) {
int cpu;
cpu = array_index_nospec(p->sq_thread_cpu, NR_CPUS);
+ ret = -EINVAL;
+ if (!cpu_possible(p->sq_thread_cpu))
+ goto err;
+
ctx->sqo_thread = kthread_create_on_cpu(io_sq_thread,
ctx, cpu,
"io_uring-sq");
@@ -2922,11 +2929,23 @@ SYSCALL_DEFINE2(io_uring_setup, u32, entries,
static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
void __user *arg, unsigned nr_args)
+ __releases(ctx->uring_lock)
+ __acquires(ctx->uring_lock)
{
int ret;
percpu_ref_kill(&ctx->refs);
+
+ /*
+ * Drop uring mutex before waiting for references to exit. If another
+ * thread is currently inside io_uring_enter() it might need to grab
+ * the uring_lock to make progress. If we hold it here across the drain
+ * wait, then we can deadlock. It's safe to drop the mutex here, since
+ * no new references will come in after we've killed the percpu ref.
+ */
+ mutex_unlock(&ctx->uring_lock);
wait_for_completion(&ctx->ctx_done);
+ mutex_lock(&ctx->uring_lock);
switch (opcode) {
case IORING_REGISTER_BUFFERS:
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 5c58a3b2bf00..317ab30d2904 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -548,7 +548,6 @@ struct request_queue {
struct rcu_head rcu_head;
wait_queue_head_t mq_freeze_wq;
struct percpu_ref q_usage_counter;
- struct list_head all_q_node;
struct blk_mq_tag_set *tag_set;
struct list_head tag_set_list;
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 3bc91879e1e2..ff13cbc1887d 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -160,8 +160,9 @@ static inline void bvec_advance(const struct bio_vec *bvec,
bv->bv_page = nth_page(bv->bv_page, 1);
bv->bv_offset = 0;
} else {
- bv->bv_page = bvec->bv_page;
- bv->bv_offset = bvec->bv_offset;
+ bv->bv_page = bvec_nth_page(bvec->bv_page, bvec->bv_offset /
+ PAGE_SIZE);
+ bv->bv_offset = bvec->bv_offset & ~PAGE_MASK;
}
bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset,
bvec->bv_len - iter_all->done);
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 2e9e2763bf47..6e8bc53740f0 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -31,6 +31,7 @@ struct elevator_mq_ops {
void (*exit_sched)(struct elevator_queue *);
int (*init_hctx)(struct blk_mq_hw_ctx *, unsigned int);
void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);
+ void (*depth_updated)(struct blk_mq_hw_ctx *);
bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
bool (*bio_merge)(struct blk_mq_hw_ctx *, struct bio *);