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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-23 10:25:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-23 10:25:12 -0700
commit1bdd3dbfff7a308643c7f9ef74e4a8ef3923e686 (patch)
treed909952844644eefba33baabb267ad49195973b5 /fs
parent2335cbe648e7163e78b3f85cd61816271d1a4313 (diff)
parent399254aaf4892113c806816f7e64cf40c804d46d (diff)
downloadlinux-stericsson-1bdd3dbfff7a308643c7f9ef74e4a8ef3923e686.tar.gz
Merge tag 'io_uring-20190323' of git://git.kernel.dk/linux-block
Pull io_uring fixes and improvements from Jens Axboe: "The first five in this series are heavily inspired by the work Al did on the aio side to fix the races there. The last two re-introduce a feature that was in io_uring before it got merged, but which I pulled since we didn't have a good way to have BVEC iters that already have a stable reference. These aren't necessarily related to block, it's just how io_uring pins fixed buffers" * tag 'io_uring-20190323' of git://git.kernel.dk/linux-block: block: add BIO_NO_PAGE_REF flag iov_iter: add ITER_BVEC_FLAG_NO_REF flag io_uring: mark me as the maintainer io_uring: retry bulk slab allocs as single allocs io_uring: fix poll races io_uring: fix fget/fput handling io_uring: add prepped flag io_uring: make io_read/write return an integer io_uring: use regular request ref counts
Diffstat (limited to 'fs')
-rw-r--r--fs/block_dev.c12
-rw-r--r--fs/io_uring.c439
-rw-r--r--fs/iomap.c12
3 files changed, 230 insertions, 233 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c
index e9faa52bb489..78d3257435c0 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -336,12 +336,14 @@ static void blkdev_bio_end_io(struct bio *bio)
if (should_dirty) {
bio_check_pages_dirty(bio);
} else {
- struct bio_vec *bvec;
- int i;
- struct bvec_iter_all iter_all;
+ if (!bio_flagged(bio, BIO_NO_PAGE_REF)) {
+ struct bvec_iter_all iter_all;
+ struct bio_vec *bvec;
+ int i;
- bio_for_each_segment_all(bvec, bio, i, iter_all)
- put_page(bvec->bv_page);
+ bio_for_each_segment_all(bvec, bio, i, iter_all)
+ put_page(bvec->bv_page);
+ }
bio_put(bio);
}
}
diff --git a/fs/io_uring.c b/fs/io_uring.c
index c88088d92613..6aaa30580a2b 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -189,17 +189,28 @@ struct sqe_submit {
bool needs_fixed_file;
};
+/*
+ * First field must be the file pointer in all the
+ * iocb unions! See also 'struct kiocb' in <linux/fs.h>
+ */
struct io_poll_iocb {
struct file *file;
struct wait_queue_head *head;
__poll_t events;
- bool woken;
+ bool done;
bool canceled;
struct wait_queue_entry wait;
};
+/*
+ * NOTE! Each of the iocb union members has the file pointer
+ * as the first entry in their struct definition. So you can
+ * access the file pointer through any of the sub-structs,
+ * or directly as just 'ki_filp' in this struct.
+ */
struct io_kiocb {
union {
+ struct file *file;
struct kiocb rw;
struct io_poll_iocb poll;
};
@@ -214,6 +225,7 @@ struct io_kiocb {
#define REQ_F_IOPOLL_COMPLETED 2 /* polled IO has completed */
#define REQ_F_FIXED_FILE 4 /* ctx owns file */
#define REQ_F_SEQ_PREV 8 /* sequential with previous */
+#define REQ_F_PREPPED 16 /* prep already done */
u64 user_data;
u64 error;
@@ -355,20 +367,25 @@ static void io_cqring_fill_event(struct io_ring_ctx *ctx, u64 ki_user_data,
}
}
-static void io_cqring_add_event(struct io_ring_ctx *ctx, u64 ki_user_data,
+static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
+{
+ if (waitqueue_active(&ctx->wait))
+ wake_up(&ctx->wait);
+ if (waitqueue_active(&ctx->sqo_wait))
+ wake_up(&ctx->sqo_wait);
+}
+
+static void io_cqring_add_event(struct io_ring_ctx *ctx, u64 user_data,
long res, unsigned ev_flags)
{
unsigned long flags;
spin_lock_irqsave(&ctx->completion_lock, flags);
- io_cqring_fill_event(ctx, ki_user_data, res, ev_flags);
+ io_cqring_fill_event(ctx, user_data, res, ev_flags);
io_commit_cqring(ctx);
spin_unlock_irqrestore(&ctx->completion_lock, flags);
- if (waitqueue_active(&ctx->wait))
- wake_up(&ctx->wait);
- if (waitqueue_active(&ctx->sqo_wait))
- wake_up(&ctx->sqo_wait);
+ io_cqring_ev_posted(ctx);
}
static void io_ring_drop_ctx_refs(struct io_ring_ctx *ctx, unsigned refs)
@@ -382,13 +399,14 @@ static void io_ring_drop_ctx_refs(struct io_ring_ctx *ctx, unsigned refs)
static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx,
struct io_submit_state *state)
{
+ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
struct io_kiocb *req;
if (!percpu_ref_tryget(&ctx->refs))
return NULL;
if (!state) {
- req = kmem_cache_alloc(req_cachep, __GFP_NOWARN);
+ req = kmem_cache_alloc(req_cachep, gfp);
if (unlikely(!req))
goto out;
} else if (!state->free_reqs) {
@@ -396,10 +414,18 @@ static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx,
int ret;
sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs));
- ret = kmem_cache_alloc_bulk(req_cachep, __GFP_NOWARN, sz,
- state->reqs);
- if (unlikely(ret <= 0))
- goto out;
+ ret = kmem_cache_alloc_bulk(req_cachep, gfp, sz, state->reqs);
+
+ /*
+ * Bulk alloc is all-or-nothing. If we fail to get a batch,
+ * retry single alloc to be on the safe side.
+ */
+ if (unlikely(ret <= 0)) {
+ state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
+ if (!state->reqs[0])
+ goto out;
+ ret = 1;
+ }
state->free_reqs = ret - 1;
state->cur_req = 1;
req = state->reqs[0];
@@ -411,7 +437,8 @@ static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx,
req->ctx = ctx;
req->flags = 0;
- refcount_set(&req->refs, 0);
+ /* one is dropped after submission, the other at completion */
+ refcount_set(&req->refs, 2);
return req;
out:
io_ring_drop_ctx_refs(ctx, 1);
@@ -429,10 +456,16 @@ static void io_free_req_many(struct io_ring_ctx *ctx, void **reqs, int *nr)
static void io_free_req(struct io_kiocb *req)
{
- if (!refcount_read(&req->refs) || refcount_dec_and_test(&req->refs)) {
- io_ring_drop_ctx_refs(req->ctx, 1);
- kmem_cache_free(req_cachep, req);
- }
+ if (req->file && !(req->flags & REQ_F_FIXED_FILE))
+ fput(req->file);
+ io_ring_drop_ctx_refs(req->ctx, 1);
+ kmem_cache_free(req_cachep, req);
+}
+
+static void io_put_req(struct io_kiocb *req)
+{
+ if (refcount_dec_and_test(&req->refs))
+ io_free_req(req);
}
/*
@@ -442,44 +475,34 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
struct list_head *done)
{
void *reqs[IO_IOPOLL_BATCH];
- int file_count, to_free;
- struct file *file = NULL;
struct io_kiocb *req;
+ int to_free;
- file_count = to_free = 0;
+ to_free = 0;
while (!list_empty(done)) {
req = list_first_entry(done, struct io_kiocb, list);
list_del(&req->list);
io_cqring_fill_event(ctx, req->user_data, req->error, 0);
-
- reqs[to_free++] = req;
(*nr_events)++;
- /*
- * Batched puts of the same file, to avoid dirtying the
- * file usage count multiple times, if avoidable.
- */
- if (!(req->flags & REQ_F_FIXED_FILE)) {
- if (!file) {
- file = req->rw.ki_filp;
- file_count = 1;
- } else if (file == req->rw.ki_filp) {
- file_count++;
+ if (refcount_dec_and_test(&req->refs)) {
+ /* If we're not using fixed files, we have to pair the
+ * completion part with the file put. Use regular
+ * completions for those, only batch free for fixed
+ * file.
+ */
+ if (req->flags & REQ_F_FIXED_FILE) {
+ reqs[to_free++] = req;
+ if (to_free == ARRAY_SIZE(reqs))
+ io_free_req_many(ctx, reqs, &to_free);
} else {
- fput_many(file, file_count);
- file = req->rw.ki_filp;
- file_count = 1;
+ io_free_req(req);
}
}
-
- if (to_free == ARRAY_SIZE(reqs))
- io_free_req_many(ctx, reqs, &to_free);
}
- io_commit_cqring(ctx);
- if (file)
- fput_many(file, file_count);
+ io_commit_cqring(ctx);
io_free_req_many(ctx, reqs, &to_free);
}
@@ -602,21 +625,14 @@ static void kiocb_end_write(struct kiocb *kiocb)
}
}
-static void io_fput(struct io_kiocb *req)
-{
- if (!(req->flags & REQ_F_FIXED_FILE))
- fput(req->rw.ki_filp);
-}
-
static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
{
struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw);
kiocb_end_write(kiocb);
- io_fput(req);
io_cqring_add_event(req->ctx, req->user_data, res, 0);
- io_free_req(req);
+ io_put_req(req);
}
static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
@@ -731,31 +747,18 @@ static int io_prep_rw(struct io_kiocb *req, const struct sqe_submit *s,
const struct io_uring_sqe *sqe = s->sqe;
struct io_ring_ctx *ctx = req->ctx;
struct kiocb *kiocb = &req->rw;
- unsigned ioprio, flags;
- int fd, ret;
+ unsigned ioprio;
+ int ret;
+ if (!req->file)
+ return -EBADF;
/* For -EAGAIN retry, everything is already prepped */
- if (kiocb->ki_filp)
+ if (req->flags & REQ_F_PREPPED)
return 0;
- flags = READ_ONCE(sqe->flags);
- fd = READ_ONCE(sqe->fd);
+ if (force_nonblock && !io_file_supports_async(req->file))
+ force_nonblock = false;
- if (flags & IOSQE_FIXED_FILE) {
- if (unlikely(!ctx->user_files ||
- (unsigned) fd >= ctx->nr_user_files))
- return -EBADF;
- kiocb->ki_filp = ctx->user_files[fd];
- req->flags |= REQ_F_FIXED_FILE;
- } else {
- if (s->needs_fixed_file)
- return -EBADF;
- kiocb->ki_filp = io_file_get(state, fd);
- if (unlikely(!kiocb->ki_filp))
- return -EBADF;
- if (force_nonblock && !io_file_supports_async(kiocb->ki_filp))
- force_nonblock = false;
- }
kiocb->ki_pos = READ_ONCE(sqe->off);
kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
@@ -764,7 +767,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct sqe_submit *s,
if (ioprio) {
ret = ioprio_check_cap(ioprio);
if (ret)
- goto out_fput;
+ return ret;
kiocb->ki_ioprio = ioprio;
} else
@@ -772,38 +775,26 @@ static int io_prep_rw(struct io_kiocb *req, const struct sqe_submit *s,
ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
if (unlikely(ret))
- goto out_fput;
+ return ret;
if (force_nonblock) {
kiocb->ki_flags |= IOCB_NOWAIT;
req->flags |= REQ_F_FORCE_NONBLOCK;
}
if (ctx->flags & IORING_SETUP_IOPOLL) {
- ret = -EOPNOTSUPP;
if (!(kiocb->ki_flags & IOCB_DIRECT) ||
!kiocb->ki_filp->f_op->iopoll)
- goto out_fput;
+ return -EOPNOTSUPP;
req->error = 0;
kiocb->ki_flags |= IOCB_HIPRI;
kiocb->ki_complete = io_complete_rw_iopoll;
} else {
- if (kiocb->ki_flags & IOCB_HIPRI) {
- ret = -EINVAL;
- goto out_fput;
- }
+ if (kiocb->ki_flags & IOCB_HIPRI)
+ return -EINVAL;
kiocb->ki_complete = io_complete_rw;
}
+ req->flags |= REQ_F_PREPPED;
return 0;
-out_fput:
- if (!(flags & IOSQE_FIXED_FILE)) {
- /*
- * in case of error, we didn't use this file reference. drop it.
- */
- if (state)
- state->used_refs--;
- io_file_put(state, kiocb->ki_filp);
- }
- return ret;
}
static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
@@ -864,6 +855,9 @@ static int io_import_fixed(struct io_ring_ctx *ctx, int rw,
iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
if (offset)
iov_iter_advance(iter, offset);
+
+ /* don't drop a reference to these pages */
+ iter->type |= ITER_BVEC_FLAG_NO_REF;
return 0;
}
@@ -887,7 +881,7 @@ static int io_import_iovec(struct io_ring_ctx *ctx, int rw,
opcode = READ_ONCE(sqe->opcode);
if (opcode == IORING_OP_READ_FIXED ||
opcode == IORING_OP_WRITE_FIXED) {
- ssize_t ret = io_import_fixed(ctx, rw, sqe, iter);
+ int ret = io_import_fixed(ctx, rw, sqe, iter);
*iovec = NULL;
return ret;
}
@@ -945,31 +939,29 @@ static void io_async_list_note(int rw, struct io_kiocb *req, size_t len)
async_list->io_end = io_end;
}
-static ssize_t io_read(struct io_kiocb *req, const struct sqe_submit *s,
- bool force_nonblock, struct io_submit_state *state)
+static int io_read(struct io_kiocb *req, const struct sqe_submit *s,
+ bool force_nonblock, struct io_submit_state *state)
{
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
struct kiocb *kiocb = &req->rw;
struct iov_iter iter;
struct file *file;
size_t iov_count;
- ssize_t ret;
+ int ret;
ret = io_prep_rw(req, s, force_nonblock, state);
if (ret)
return ret;
file = kiocb->ki_filp;
- ret = -EBADF;
if (unlikely(!(file->f_mode & FMODE_READ)))
- goto out_fput;
- ret = -EINVAL;
+ return -EBADF;
if (unlikely(!file->f_op->read_iter))
- goto out_fput;
+ return -EINVAL;
ret = io_import_iovec(req->ctx, READ, s, &iovec, &iter);
if (ret)
- goto out_fput;
+ return ret;
iov_count = iov_iter_count(&iter);
ret = rw_verify_area(READ, file, &kiocb->ki_pos, iov_count);
@@ -991,38 +983,32 @@ static ssize_t io_read(struct io_kiocb *req, const struct sqe_submit *s,
}
}
kfree(iovec);
-out_fput:
- /* Hold on to the file for -EAGAIN */
- if (unlikely(ret && ret != -EAGAIN))
- io_fput(req);
return ret;
}
-static ssize_t io_write(struct io_kiocb *req, const struct sqe_submit *s,
- bool force_nonblock, struct io_submit_state *state)
+static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
+ bool force_nonblock, struct io_submit_state *state)
{
struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
struct kiocb *kiocb = &req->rw;
struct iov_iter iter;
struct file *file;
size_t iov_count;
- ssize_t ret;
+ int ret;
ret = io_prep_rw(req, s, force_nonblock, state);
if (ret)
return ret;
- ret = -EBADF;
file = kiocb->ki_filp;
if (unlikely(!(file->f_mode & FMODE_WRITE)))
- goto out_fput;
- ret = -EINVAL;
+ return -EBADF;
if (unlikely(!file->f_op->write_iter))
- goto out_fput;
+ return -EINVAL;
ret = io_import_iovec(req->ctx, WRITE, s, &iovec, &iter);
if (ret)
- goto out_fput;
+ return ret;
iov_count = iov_iter_count(&iter);
@@ -1054,10 +1040,6 @@ static ssize_t io_write(struct io_kiocb *req, const struct sqe_submit *s,
}
out_free:
kfree(iovec);
-out_fput:
- /* Hold on to the file for -EAGAIN */
- if (unlikely(ret && ret != -EAGAIN))
- io_fput(req);
return ret;
}
@@ -1072,29 +1054,19 @@ static int io_nop(struct io_kiocb *req, u64 user_data)
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
- /*
- * Twilight zone - it's possible that someone issued an opcode that
- * has a file attached, then got -EAGAIN on submission, and changed
- * the sqe before we retried it from async context. Avoid dropping
- * a file reference for this malicious case, and flag the error.
- */
- if (req->rw.ki_filp) {
- err = -EBADF;
- io_fput(req);
- }
io_cqring_add_event(ctx, user_data, err, 0);
- io_free_req(req);
+ io_put_req(req);
return 0;
}
static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_ring_ctx *ctx = req->ctx;
- unsigned flags;
- int fd;
- /* Prep already done */
- if (req->rw.ki_filp)
+ if (!req->file)
+ return -EBADF;
+ /* Prep already done (EAGAIN retry) */
+ if (req->flags & REQ_F_PREPPED)
return 0;
if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
@@ -1102,20 +1074,7 @@ static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe)
if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
return -EINVAL;
- fd = READ_ONCE(sqe->fd);
- flags = READ_ONCE(sqe->flags);
-
- if (flags & IOSQE_FIXED_FILE) {
- if (unlikely(!ctx->user_files || fd >= ctx->nr_user_files))
- return -EBADF;
- req->rw.ki_filp = ctx->user_files[fd];
- req->flags |= REQ_F_FIXED_FILE;
- } else {
- req->rw.ki_filp = fget(fd);
- if (unlikely(!req->rw.ki_filp))
- return -EBADF;
- }
-
+ req->flags |= REQ_F_PREPPED;
return 0;
}
@@ -1144,9 +1103,8 @@ static int io_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe,
end > 0 ? end : LLONG_MAX,
fsync_flags & IORING_FSYNC_DATASYNC);
- io_fput(req);
io_cqring_add_event(req->ctx, sqe->user_data, ret, 0);
- io_free_req(req);
+ io_put_req(req);
return 0;
}
@@ -1204,15 +1162,16 @@ static int io_poll_remove(struct io_kiocb *req, const struct io_uring_sqe *sqe)
spin_unlock_irq(&ctx->completion_lock);
io_cqring_add_event(req->ctx, sqe->user_data, ret, 0);
- io_free_req(req);
+ io_put_req(req);
return 0;
}
-static void io_poll_complete(struct io_kiocb *req, __poll_t mask)
+static void io_poll_complete(struct io_ring_ctx *ctx, struct io_kiocb *req,
+ __poll_t mask)
{
- io_cqring_add_event(req->ctx, req->user_data, mangle_poll(mask), 0);
- io_fput(req);
- io_free_req(req);
+ req->poll.done = true;
+ io_cqring_fill_event(ctx, req->user_data, mangle_poll(mask), 0);
+ io_commit_cqring(ctx);
}
static void io_poll_complete_work(struct work_struct *work)
@@ -1240,9 +1199,11 @@ static void io_poll_complete_work(struct work_struct *work)
return;
}
list_del_init(&req->list);
+ io_poll_complete(ctx, req, mask);
spin_unlock_irq(&ctx->completion_lock);
- io_poll_complete(req, mask);
+ io_cqring_ev_posted(ctx);
+ io_put_req(req);
}
static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
@@ -1253,29 +1214,25 @@ static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
struct io_kiocb *req = container_of(poll, struct io_kiocb, poll);
struct io_ring_ctx *ctx = req->ctx;
__poll_t mask = key_to_poll(key);
-
- poll->woken = true;
+ unsigned long flags;
/* for instances that support it check for an event match first: */
- if (mask) {
- unsigned long flags;
+ if (mask && !(mask & poll->events))
+ return 0;
- if (!(mask & poll->events))
- return 0;
+ list_del_init(&poll->wait.entry);
- /* try to complete the iocb inline if we can: */
- if (spin_trylock_irqsave(&ctx->completion_lock, flags)) {
- list_del(&req->list);
- spin_unlock_irqrestore(&ctx->completion_lock, flags);
+ if (mask && spin_trylock_irqsave(&ctx->completion_lock, flags)) {
+ list_del(&req->list);
+ io_poll_complete(ctx, req, mask);
+ spin_unlock_irqrestore(&ctx->completion_lock, flags);
- list_del_init(&poll->wait.entry);
- io_poll_complete(req, mask);
- return 1;
- }
+ io_cqring_ev_posted(ctx);
+ io_put_req(req);
+ } else {
+ queue_work(ctx->sqo_wq, &req->work);
}
- list_del_init(&poll->wait.entry);
- queue_work(ctx->sqo_wq, &req->work);
return 1;
}
@@ -1305,36 +1262,23 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe)
struct io_poll_iocb *poll = &req->poll;
struct io_ring_ctx *ctx = req->ctx;
struct io_poll_table ipt;
- unsigned flags;
+ bool cancel = false;
__poll_t mask;
u16 events;
- int fd;
if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
return -EINVAL;
if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
return -EINVAL;
+ if (!poll->file)
+ return -EBADF;
INIT_WORK(&req->work, io_poll_complete_work);
events = READ_ONCE(sqe->poll_events);
poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP;
- flags = READ_ONCE(sqe->flags);
- fd = READ_ONCE(sqe->fd);
-
- if (flags & IOSQE_FIXED_FILE) {
- if (unlikely(!ctx->user_files || fd >= ctx->nr_user_files))
- return -EBADF;
- poll->file = ctx->user_files[fd];
- req->flags |= REQ_F_FIXED_FILE;
- } else {
- poll->file = fget(fd);
- }
- if (unlikely(!poll->file))
- return -EBADF;
-
poll->head = NULL;
- poll->woken = false;
+ poll->done = false;
poll->canceled = false;
ipt.pt._qproc = io_poll_queue_proc;
@@ -1346,56 +1290,44 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe)
INIT_LIST_HEAD(&poll->wait.entry);
init_waitqueue_func_entry(&poll->wait, io_poll_wake);
- /* one for removal from waitqueue, one for this function */
- refcount_set(&req->refs, 2);
-
mask = vfs_poll(poll->file, &ipt.pt) & poll->events;
- if (unlikely(!poll->head)) {
- /* we did not manage to set up a waitqueue, done */
- goto out;
- }
spin_lock_irq(&ctx->completion_lock);
- spin_lock(&poll->head->lock);
- if (poll->woken) {
- /* wake_up context handles the rest */
- mask = 0;
+ if (likely(poll->head)) {
+ spin_lock(&poll->head->lock);
+ if (unlikely(list_empty(&poll->wait.entry))) {
+ if (ipt.error)
+ cancel = true;
+ ipt.error = 0;
+ mask = 0;
+ }
+ if (mask || ipt.error)
+ list_del_init(&poll->wait.entry);
+ else if (cancel)
+ WRITE_ONCE(poll->canceled, true);
+ else if (!poll->done) /* actually waiting for an event */
+ list_add_tail(&req->list, &ctx->cancel_list);
+ spin_unlock(&poll->head->lock);
+ }
+ if (mask) { /* no async, we'd stolen it */
+ req->error = mangle_poll(mask);
ipt.error = 0;
- } else if (mask || ipt.error) {
- /* if we get an error or a mask we are done */
- WARN_ON_ONCE(list_empty(&poll->wait.entry));
- list_del_init(&poll->wait.entry);
- } else {
- /* actually waiting for an event */
- list_add_tail(&req->list, &ctx->cancel_list);
+ io_poll_complete(ctx, req, mask);
}
- spin_unlock(&poll->head->lock);
spin_unlock_irq(&ctx->completion_lock);
-out:
- if (unlikely(ipt.error)) {
- if (!(flags & IOSQE_FIXED_FILE))
- fput(poll->file);
- /*
- * Drop one of our refs to this req, __io_submit_sqe() will
- * drop the other one since we're returning an error.
- */
- io_free_req(req);
- return ipt.error;
+ if (mask) {
+ io_cqring_ev_posted(ctx);
+ io_put_req(req);
}
-
- if (mask)
- io_poll_complete(req, mask);
- io_free_req(req);
- return 0;
+ return ipt.error;
}
static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
const struct sqe_submit *s, bool force_nonblock,
struct io_submit_state *state)
{
- ssize_t ret;
- int opcode;
+ int ret, opcode;
if (unlikely(s->index >= ctx->sq_entries))
return -EINVAL;
@@ -1524,10 +1456,13 @@ restart:
break;
cond_resched();
} while (1);
+
+ /* drop submission reference */
+ io_put_req(req);
}
if (ret) {
io_cqring_add_event(ctx, sqe->user_data, ret, 0);
- io_free_req(req);
+ io_put_req(req);
}
/* async context always use a copy of the sqe */
@@ -1614,11 +1549,55 @@ static bool io_add_to_prev_work(struct async_list *list, struct io_kiocb *req)
return ret;
}
+static bool io_op_needs_file(const struct io_uring_sqe *sqe)
+{
+ int op = READ_ONCE(sqe->opcode);
+
+ switch (op) {
+ case IORING_OP_NOP:
+ case IORING_OP_POLL_REMOVE:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s,
+ struct io_submit_state *state, struct io_kiocb *req)
+{
+ unsigned flags;
+ int fd;
+
+ flags = READ_ONCE(s->sqe->flags);
+ fd = READ_ONCE(s->sqe->fd);
+
+ if (!io_op_needs_file(s->sqe)) {
+ req->file = NULL;
+ return 0;
+ }
+
+ if (flags & IOSQE_FIXED_FILE) {
+ if (unlikely(!ctx->user_files ||
+ (unsigned) fd >= ctx->nr_user_files))
+ return -EBADF;
+ req->file = ctx->user_files[fd];
+ req->flags |= REQ_F_FIXED_FILE;
+ } else {
+ if (s->needs_fixed_file)
+ return -EBADF;
+ req->file = io_file_get(state, fd);
+ if (unlikely(!req->file))
+ return -EBADF;
+ }
+
+ return 0;
+}
+
static int io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s,
struct io_submit_state *state)
{
struct io_kiocb *req;
- ssize_t ret;
+ int ret;
/* enforce forwards compatibility on users */
if (unlikely(s->sqe->flags & ~IOSQE_FIXED_FILE))
@@ -1628,7 +1607,9 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s,
if (unlikely(!req))
return -EAGAIN;
- req->rw.ki_filp = NULL;
+ ret = io_req_set_file(ctx, s, state, req);
+ if (unlikely(ret))
+ goto out;
ret = __io_submit_sqe(ctx, req, s, true, state);
if (ret == -EAGAIN) {
@@ -1649,11 +1630,23 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s,
INIT_WORK(&req->work, io_sq_wq_submit_work);
queue_work(ctx->sqo_wq, &req->work);
}
- ret = 0;
+
+ /*
+ * Queued up for async execution, worker will release
+ * submit reference when the iocb is actually
+ * submitted.
+ */
+ return 0;
}
}
+
+out:
+ /* drop submission reference */
+ io_put_req(req);
+
+ /* and drop final reference, if we failed */
if (ret)
- io_free_req(req);
+ io_put_req(req);
return ret;
}
diff --git a/fs/iomap.c b/fs/iomap.c
index 97cb9d486a7d..abdd18e404f8 100644
--- a/fs/iomap.c
+++ b/fs/iomap.c
@@ -1589,12 +1589,14 @@ static void iomap_dio_bio_end_io(struct bio *bio)
if (should_dirty) {
bio_check_pages_dirty(bio);
} else {
- struct bio_vec *bvec;
- int i;
- struct bvec_iter_all iter_all;
+ if (!bio_flagged(bio, BIO_NO_PAGE_REF)) {
+ struct bvec_iter_all iter_all;
+ struct bio_vec *bvec;
+ int i;
- bio_for_each_segment_all(bvec, bio, i, iter_all)
- put_page(bvec->bv_page);
+ bio_for_each_segment_all(bvec, bio, i, iter_all)
+ put_page(bvec->bv_page);
+ }
bio_put(bio);
}
}