diff options
| author | Zhengyuan Liu <liuzhengyuan@kylinos.cn> | 2019-07-16 23:26:14 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-31 07:25:03 +0200 |
| commit | 4686e134619cf7fc3eaf5edb3da400e3a9a751d2 (patch) | |
| tree | 5245f02154705b8d8dfb50382ddd9e6e4effe274 | |
| parent | 119be19fa6b647a9c70bd5d396c183b3c832f07b (diff) | |
io_uring: fix counter inc/dec mismatch in async_list
commit f7b76ac9d17e16e44feebb6d2749fec92bfd6dd4 upstream.
We could queue a work for each req in defer and link list without
increasing async_list->cnt, so we shouldn't decrease it while exiting
from workqueue as well if we didn't process the req in async list.
Thanks to Jens Axboe <axboe@kernel.dk> for his guidance.
Fixes: 31b515106428 ("io_uring: allow workqueue item to handle multiple buffered requests")
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/io_uring.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 294a0a76dfab..b90ca8d3cbbc 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -331,6 +331,9 @@ struct io_kiocb { #define REQ_F_SEQ_PREV 8 /* sequential with previous */ #define REQ_F_IO_DRAIN 16 /* drain existing IO first */ #define REQ_F_IO_DRAINED 32 /* drain done */ +#define REQ_F_LINK 64 /* linked sqes */ +#define REQ_F_LINK_DONE 128 /* linked sqes done */ +#define REQ_F_FAIL_LINK 256 /* fail rest of links */ u64 user_data; u32 error; /* iopoll result from callback */ u32 sequence; @@ -1698,6 +1701,10 @@ restart: /* async context always use a copy of the sqe */ kfree(sqe); + /* req from defer and link list needn't decrease async cnt */ + if (req->flags & (REQ_F_IO_DRAINED | REQ_F_LINK_DONE)) + goto out; + if (!async_list) break; if (!list_empty(&req_list)) { @@ -1745,6 +1752,7 @@ restart: } } +out: if (cur_mm) { set_fs(old_fs); unuse_mm(cur_mm); |