io_uring: encapsulate rw state
Add a new struct io_rw_state storing all iov related bits: fast iov,
iterator and iterator state. Not much changes here, simply convert
struct io_async_rw to use it.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e8245ffcb568b228a009ec1eb79c993c813679f1.1634144845.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 18a91d2..4736561 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -694,11 +694,15 @@ struct io_async_msghdr {
struct sockaddr_storage addr;
};
-struct io_async_rw {
+struct io_rw_state {
struct iovec fast_iov[UIO_FASTIOV];
- const struct iovec *free_iovec;
struct iov_iter iter;
struct iov_iter_state iter_state;
+};
+
+struct io_async_rw {
+ struct io_rw_state s;
+ const struct iovec *free_iovec;
size_t bytes_done;
struct wait_page_queue wpq;
};
@@ -2596,7 +2600,7 @@ static bool io_resubmit_prep(struct io_kiocb *req)
if (!req_has_async_data(req))
return !io_req_prep_async(req);
- iov_iter_restore(&rw->iter, &rw->iter_state);
+ iov_iter_restore(&rw->s.iter, &rw->s.iter_state);
return true;
}
@@ -3259,7 +3263,7 @@ static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
{
struct io_async_rw *rw = req->async_data;
- memcpy(&rw->iter, iter, sizeof(*iter));
+ memcpy(&rw->s.iter, iter, sizeof(*iter));
rw->free_iovec = iovec;
rw->bytes_done = 0;
/* can only be fixed buffers, no need to do anything */
@@ -3268,13 +3272,13 @@ static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
if (!iovec) {
unsigned iov_off = 0;
- rw->iter.iov = rw->fast_iov;
+ rw->s.iter.iov = rw->s.fast_iov;
if (iter->iov != fast_iov) {
iov_off = iter->iov - fast_iov;
- rw->iter.iov += iov_off;
+ rw->s.iter.iov += iov_off;
}
- if (rw->fast_iov != fast_iov)
- memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
+ if (rw->s.fast_iov != fast_iov)
+ memcpy(rw->s.fast_iov + iov_off, fast_iov + iov_off,
sizeof(struct iovec) * iter->nr_segs);
} else {
req->flags |= REQ_F_NEED_CLEANUP;
@@ -3309,7 +3313,7 @@ static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
io_req_map_rw(req, iovec, fast_iov, iter);
iorw = req->async_data;
/* we've copied and mapped the iter, ensure state is saved */
- iov_iter_save_state(&iorw->iter, &iorw->iter_state);
+ iov_iter_save_state(&iorw->s.iter, &iorw->s.iter_state);
}
return 0;
}
@@ -3317,10 +3321,10 @@ static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
{
struct io_async_rw *iorw = req->async_data;
- struct iovec *iov = iorw->fast_iov;
+ struct iovec *iov = iorw->s.fast_iov;
int ret;
- ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
+ ret = io_import_iovec(rw, req, &iov, &iorw->s.iter, false);
if (unlikely(ret < 0))
return ret;
@@ -3328,7 +3332,7 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
iorw->free_iovec = iov;
if (iov)
req->flags |= REQ_F_NEED_CLEANUP;
- iov_iter_save_state(&iorw->iter, &iorw->iter_state);
+ iov_iter_save_state(&iorw->s.iter, &iorw->s.iter_state);
return 0;
}
@@ -3438,8 +3442,8 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
if (req_has_async_data(req)) {
rw = req->async_data;
- iter = &rw->iter;
- state = &rw->iter_state;
+ iter = &rw->s.iter;
+ state = &rw->s.iter_state;
/*
* We come here from an earlier attempt, restore our state to
* match in case it doesn't. It's cheap enough that we don't
@@ -3510,9 +3514,9 @@ static int io_read(struct io_kiocb *req, unsigned int issue_flags)
* Now use our persistent iterator and state, if we aren't already.
* We've restored and mapped the iter to match.
*/
- if (iter != &rw->iter) {
- iter = &rw->iter;
- state = &rw->iter_state;
+ if (iter != &rw->s.iter) {
+ iter = &rw->s.iter;
+ state = &rw->s.iter_state;
}
do {
@@ -3574,8 +3578,8 @@ static int io_write(struct io_kiocb *req, unsigned int issue_flags)
if (req_has_async_data(req)) {
rw = req->async_data;
- iter = &rw->iter;
- state = &rw->iter_state;
+ iter = &rw->s.iter;
+ state = &rw->s.iter_state;
iov_iter_restore(iter, state);
iovec = NULL;
} else {