io_uring/rw: don't mask in f_iocb_flags

A previous commit changed overwriting kiocb->ki_flags with
->f_iocb_flags with masking it in. This breaks for retry situations,
where we don't necessarily want to retain previously set flags, like
IOCB_NOWAIT.

The use case needs IOCB_HAS_METADATA to be persistent, but the change
makes all flags persistent, which is an issue. Add a request flag to
track whether the request has metadata or not, as that is persistent
across issues.

Fixes: 59a7d12a7fb5 ("io_uring: introduce attributes for read/write and PI support")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 73575d545d3c072644b4279af9a4f9dae568be58..623d8e798a11a5d535ed1b0bb5bab350c89fad01 100644 (file)
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -480,6 +480,7 @@ enum {
        REQ_F_BL_NO_RECYCLE_BIT,
        REQ_F_BUFFERS_COMMIT_BIT,
        REQ_F_BUF_NODE_BIT,
+       REQ_F_HAS_METADATA_BIT,
 
        /* not a real bit, just to check we're not overflowing the space */
        __REQ_F_LAST_BIT,
@@ -560,6 +561,8 @@ enum {
        REQ_F_BUFFERS_COMMIT    = IO_REQ_FLAG(REQ_F_BUFFERS_COMMIT_BIT),
        /* buf node is valid */
        REQ_F_BUF_NODE          = IO_REQ_FLAG(REQ_F_BUF_NODE_BIT),
+       /* request has read/write metadata assigned */
+       REQ_F_HAS_METADATA      = IO_REQ_FLAG(REQ_F_HAS_METADATA_BIT),
 };
 
 typedef void (*io_req_tw_func_t)(struct io_kiocb *req, struct io_tw_state *ts);

diff --git a/io_uring/rw.c b/io_uring/rw.c
index bdfc3faef85db255324ac407386b4c03d5ab5a9a..d0ac4a51420ee2924caec5223bfa9c93644a05f8 100644 (file)
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -283,7 +283,7 @@ static int io_prep_rw_pi(struct io_kiocb *req, struct io_rw *rw, int ddir,
                          pi_attr.len, &io->meta.iter);
        if (unlikely(ret < 0))
                return ret;
-       rw->kiocb.ki_flags |= IOCB_HAS_METADATA;
+       req->flags |= REQ_F_HAS_METADATA;
        io_meta_save_state(io);
        return ret;
 }
@@ -787,18 +787,17 @@ static bool io_rw_should_retry(struct io_kiocb *req)
        struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw);
        struct kiocb *kiocb = &rw->kiocb;
 
-       /* never retry for NOWAIT, we just complete with -EAGAIN */
-       if (req->flags & REQ_F_NOWAIT)
+       /*
+        * Never retry for NOWAIT or a request with metadata, we just complete
+        * with -EAGAIN.
+        */
+       if (req->flags & (REQ_F_NOWAIT | REQ_F_HAS_METADATA))
                return false;
 
        /* Only for buffered IO */
        if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
                return false;
 
-       /* never retry for meta io */
-       if (kiocb->ki_flags & IOCB_HAS_METADATA)
-               return false;
-
        /*
         * just use poll if we can, and don't attempt if the fs doesn't
         * support callback based unlocks
@@ -849,7 +848,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode, int rw_type)
        if (!(req->flags & REQ_F_FIXED_FILE))
                req->flags |= io_file_get_flags(file);
 
-       kiocb->ki_flags |= file->f_iocb_flags;
+       kiocb->ki_flags = file->f_iocb_flags;
        ret = kiocb_set_rw_flags(kiocb, rw->flags, rw_type);
        if (unlikely(ret))
                return ret;
@@ -883,7 +882,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode, int rw_type)
                kiocb->ki_complete = io_complete_rw;
        }
 
-       if (kiocb->ki_flags & IOCB_HAS_METADATA) {
+       if (req->flags & REQ_F_HAS_METADATA) {
                struct io_async_rw *io = req->async_data;
 
                /*
@@ -892,6 +891,7 @@ static int io_rw_init_file(struct io_kiocb *req, fmode_t mode, int rw_type)
                 */
                if (!(req->file->f_flags & O_DIRECT))
                        return -EOPNOTSUPP;
+               kiocb->ki_flags |= IOCB_HAS_METADATA;
                kiocb->private = &io->meta;
        }