diff options
| author | Jens Axboe <axboe@kernel.dk> | 2020-02-07 16:05:21 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-02-08 13:07:00 -0700 |
| commit | ff002b30181d30cdfbca316dadd099c3ca0d739c (patch) | |
| tree | ba32d4f78d1a059383fff73d3f36156ef1beb721 /fs/io_uring.c | |
| parent | 9392a27d88b9707145d713654eb26f0c29789e50 (diff) | |
| download | linux-ff002b30181d30cdfbca316dadd099c3ca0d739c.tar.bz2 | |
io_uring: grab ->fs as part of async preparation
This passes it in to io-wq, so it assumes the right fs_struct when
executing async work that may need to do lookups.
Cc: stable@vger.kernel.org # 5.3+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 1a3ca6577a10..2a7bb178986e 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -75,6 +75,7 @@ #include <linux/fsnotify.h> #include <linux/fadvise.h> #include <linux/eventpoll.h> +#include <linux/fs_struct.h> #define CREATE_TRACE_POINTS #include <trace/events/io_uring.h> @@ -611,6 +612,8 @@ struct io_op_def { unsigned not_supported : 1; /* needs file table */ unsigned file_table : 1; + /* needs ->fs */ + unsigned needs_fs : 1; }; static const struct io_op_def io_op_defs[] = { @@ -653,12 +656,14 @@ static const struct io_op_def io_op_defs[] = { .needs_mm = 1, .needs_file = 1, .unbound_nonreg_file = 1, + .needs_fs = 1, }, [IORING_OP_RECVMSG] = { .async_ctx = 1, .needs_mm = 1, .needs_file = 1, .unbound_nonreg_file = 1, + .needs_fs = 1, }, [IORING_OP_TIMEOUT] = { .async_ctx = 1, @@ -689,6 +694,7 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .fd_non_neg = 1, .file_table = 1, + .needs_fs = 1, }, [IORING_OP_CLOSE] = { .needs_file = 1, @@ -702,6 +708,7 @@ static const struct io_op_def io_op_defs[] = { .needs_mm = 1, .needs_file = 1, .fd_non_neg = 1, + .needs_fs = 1, }, [IORING_OP_READ] = { .needs_mm = 1, @@ -733,6 +740,7 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .fd_non_neg = 1, .file_table = 1, + .needs_fs = 1, }, [IORING_OP_EPOLL_CTL] = { .unbound_nonreg_file = 1, @@ -907,6 +915,16 @@ static inline void io_req_work_grab_env(struct io_kiocb *req, } if (!req->work.creds) req->work.creds = get_current_cred(); + if (!req->work.fs && def->needs_fs) { + spin_lock(¤t->fs->lock); + if (!current->fs->in_exec) { + req->work.fs = current->fs; + req->work.fs->users++; + } else { + req->work.flags |= IO_WQ_WORK_CANCEL; + } + spin_unlock(¤t->fs->lock); + } } static inline void io_req_work_drop_env(struct io_kiocb *req) @@ -919,6 +937,16 @@ static inline void io_req_work_drop_env(struct io_kiocb *req) put_cred(req->work.creds); req->work.creds = NULL; } + if (req->work.fs) { + struct fs_struct *fs = req->work.fs; + + spin_lock(&req->work.fs->lock); + if (--fs->users) + fs = NULL; + spin_unlock(&req->work.fs->lock); + if (fs) + free_fs_struct(fs); + } } static inline bool io_prep_async_work(struct io_kiocb *req, |