io_uring: split logic of force_nonblock

Currently force_nonblock stands for three meanings:
 - nowait or not
 - in an io-worker or not(hold uring_lock or not)

Let's split the logic to two flags, IO_URING_F_NONBLOCK and
IO_URING_F_UNLOCKED for convenience of the next patch.

Suggested-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Hao Xu <haoxu@linux.alibaba.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/20211018133431.103298-1-haoxu@linux.alibaba.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index df07ce2fa6bc9c1a15bac203cde634c09b64ed4d..c87931d8b503b92870328f3e5f192fc15eb12747 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -199,6 +199,7 @@ struct io_rings {
 
 enum io_uring_cmd_flags {
        IO_URING_F_COMPLETE_DEFER       = 1,
+       IO_URING_F_UNLOCKED             = 2,
        /* int's last bit, sign checks are usually faster than a bit test */
        IO_URING_F_NONBLOCK             = INT_MIN,
 };
@@ -2706,10 +2707,10 @@ static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
 static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
 {
        struct io_ring_ctx *ctx = req->ctx;
-       const bool need_lock = !(issue_flags & IO_URING_F_NONBLOCK);
+       const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
 
        /* workqueue context doesn't hold uring_lock, grab it now */
-       if (unlikely(need_lock))
+       if (unlikely(needs_lock))
                mutex_lock(&ctx->uring_lock);
 
        /*
@@ -2737,7 +2738,7 @@ static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
        else
                wq_list_add_tail(&req->comp_list, &ctx->iopoll_list);
 
-       if (unlikely(need_lock)) {
+       if (unlikely(needs_lock)) {
                /*
                 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
                 * in sq thread task context or in io worker task context. If
@@ -2921,7 +2922,7 @@ static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
                        struct io_ring_ctx *ctx = req->ctx;
 
                        req_set_fail(req);
-                       if (!(issue_flags & IO_URING_F_NONBLOCK)) {
+                       if (issue_flags & IO_URING_F_UNLOCKED) {
                                mutex_lock(&ctx->uring_lock);
                                __io_req_complete(req, issue_flags, ret, cflags);
                                mutex_unlock(&ctx->uring_lock);
@@ -3031,7 +3032,7 @@ static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
 {
        struct io_buffer *kbuf = req->kbuf;
        struct io_buffer *head;
-       bool needs_lock = !(issue_flags & IO_URING_F_NONBLOCK);
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
 
        if (req->flags & REQ_F_BUFFER_SELECTED)
                return kbuf;
@@ -3336,7 +3337,7 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
        int ret;
 
        /* submission path, ->uring_lock should already be taken */
-       ret = io_import_iovec(rw, req, &iov, &iorw->s, IO_URING_F_NONBLOCK);
+       ret = io_import_iovec(rw, req, &iov, &iorw->s, 0);
        if (unlikely(ret < 0))
                return ret;
 
@@ -4309,9 +4310,9 @@ static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
        struct io_ring_ctx *ctx = req->ctx;
        struct io_buffer *head;
        int ret = 0;
-       bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
 
-       io_ring_submit_lock(ctx, !force_nonblock);
+       io_ring_submit_lock(ctx, needs_lock);
 
        lockdep_assert_held(&ctx->uring_lock);
 
@@ -4324,7 +4325,7 @@ static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
 
        /* complete before unlock, IOPOLL may need the lock */
        __io_req_complete(req, issue_flags, ret, 0);
-       io_ring_submit_unlock(ctx, !force_nonblock);
+       io_ring_submit_unlock(ctx, needs_lock);
        return 0;
 }
 
@@ -4396,9 +4397,9 @@ static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
        struct io_ring_ctx *ctx = req->ctx;
        struct io_buffer *head, *list;
        int ret = 0;
-       bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
 
-       io_ring_submit_lock(ctx, !force_nonblock);
+       io_ring_submit_lock(ctx, needs_lock);
 
        lockdep_assert_held(&ctx->uring_lock);
 
@@ -4414,7 +4415,7 @@ static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
                req_set_fail(req);
        /* complete before unlock, IOPOLL may need the lock */
        __io_req_complete(req, issue_flags, ret, 0);
-       io_ring_submit_unlock(ctx, !force_nonblock);
+       io_ring_submit_unlock(ctx, needs_lock);
        return 0;
 }
 
@@ -6271,6 +6272,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
 {
        struct io_ring_ctx *ctx = req->ctx;
        u64 sqe_addr = req->cancel.addr;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
        struct io_tctx_node *node;
        int ret;
 
@@ -6279,7 +6281,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
                goto done;
 
        /* slow path, try all io-wq's */
-       io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_lock(ctx, needs_lock);
        ret = -ENOENT;
        list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
                struct io_uring_task *tctx = node->task->io_uring;
@@ -6288,7 +6290,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
                if (ret != -ENOENT)
                        break;
        }
-       io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_unlock(ctx, needs_lock);
 done:
        if (ret < 0)
                req_set_fail(req);
@@ -6315,6 +6317,7 @@ static int io_rsrc_update_prep(struct io_kiocb *req,
 static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
 {
        struct io_ring_ctx *ctx = req->ctx;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
        struct io_uring_rsrc_update2 up;
        int ret;
 
@@ -6324,10 +6327,10 @@ static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
        up.tags = 0;
        up.resv = 0;
 
-       io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_lock(ctx, needs_lock);
        ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
                                        &up, req->rsrc_update.nr_args);
-       io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_unlock(ctx, needs_lock);
 
        if (ret < 0)
                req_set_fail(req);
@@ -6737,7 +6740,7 @@ static void io_wq_submit_work(struct io_wq_work *work)
 
        if (!ret) {
                do {
-                       ret = io_issue_sqe(req, 0);
+                       ret = io_issue_sqe(req, IO_URING_F_UNLOCKED);
                        /*
                         * We can get EAGAIN for polled IO even though we're
                         * forcing a sync submission from here, since we can't
@@ -8326,12 +8329,12 @@ static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
                                 unsigned int issue_flags, u32 slot_index)
 {
        struct io_ring_ctx *ctx = req->ctx;
-       bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
        bool needs_switch = false;
        struct io_fixed_file *file_slot;
        int ret = -EBADF;
 
-       io_ring_submit_lock(ctx, !force_nonblock);
+       io_ring_submit_lock(ctx, needs_lock);
        if (file->f_op == &io_uring_fops)
                goto err;
        ret = -ENXIO;
@@ -8372,7 +8375,7 @@ static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
 err:
        if (needs_switch)
                io_rsrc_node_switch(ctx, ctx->file_data);
-       io_ring_submit_unlock(ctx, !force_nonblock);
+       io_ring_submit_unlock(ctx, needs_lock);
        if (ret)
                fput(file);
        return ret;
@@ -8382,11 +8385,12 @@ static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
 {
        unsigned int offset = req->close.file_slot - 1;
        struct io_ring_ctx *ctx = req->ctx;
+       bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
        struct io_fixed_file *file_slot;
        struct file *file;
        int ret, i;
 
-       io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_lock(ctx, needs_lock);
        ret = -ENXIO;
        if (unlikely(!ctx->file_data))
                goto out;
@@ -8412,7 +8416,7 @@ static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
        io_rsrc_node_switch(ctx, ctx->file_data);
        ret = 0;
 out:
-       io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+       io_ring_submit_unlock(ctx, needs_lock);
        return ret;
 }