Merge branches 'pm-cpuidle', 'pm-core' and 'pm-sleep'

[linux-2.6-microblaze.git] / io_uring / msg_ring.c

diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c
index 2d3cd94..15602a1 100644 (file)
--- a/io_uring/msg_ring.c
+++ b/io_uring/msg_ring.c
@@ -25,6 +25,28 @@ struct io_msg {
        u32 flags;
 };
 
+static void io_double_unlock_ctx(struct io_ring_ctx *octx)
+{
+       mutex_unlock(&octx->uring_lock);
+}
+
+static int io_double_lock_ctx(struct io_ring_ctx *octx,
+                             unsigned int issue_flags)
+{
+       /*
+        * To ensure proper ordering between the two ctxs, we can only
+        * attempt a trylock on the target. If that fails and we already have
+        * the source ctx lock, punt to io-wq.
+        */
+       if (!(issue_flags & IO_URING_F_UNLOCKED)) {
+               if (!mutex_trylock(&octx->uring_lock))
+                       return -EAGAIN;
+               return 0;
+       }
+       mutex_lock(&octx->uring_lock);
+       return 0;
+}
+
 void io_msg_ring_cleanup(struct io_kiocb *req)
 {
        struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
@@ -36,6 +58,29 @@ void io_msg_ring_cleanup(struct io_kiocb *req)
        msg->src_file = NULL;
 }
 
+static inline bool io_msg_need_remote(struct io_ring_ctx *target_ctx)
+{
+       if (!target_ctx->task_complete)
+               return false;
+       return current != target_ctx->submitter_task;
+}
+
+static int io_msg_exec_remote(struct io_kiocb *req, task_work_func_t func)
+{
+       struct io_ring_ctx *ctx = req->file->private_data;
+       struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
+       struct task_struct *task = READ_ONCE(ctx->submitter_task);
+
+       if (unlikely(!task))
+               return -EOWNERDEAD;
+
+       init_task_work(&msg->tw, func);
+       if (task_work_add(ctx->submitter_task, &msg->tw, TWA_SIGNAL))
+               return -EOWNERDEAD;
+
+       return IOU_ISSUE_SKIP_COMPLETE;
+}
+
 static void io_msg_tw_complete(struct callback_head *head)
 {
        struct io_msg *msg = container_of(head, struct io_msg, tw);
@@ -43,61 +88,54 @@ static void io_msg_tw_complete(struct callback_head *head)
        struct io_ring_ctx *target_ctx = req->file->private_data;
        int ret = 0;
 
-       if (current->flags & PF_EXITING)
+       if (current->flags & PF_EXITING) {
                ret = -EOWNERDEAD;
-       else if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
-               ret = -EOVERFLOW;
+       } else {
+               /*
+                * If the target ring is using IOPOLL mode, then we need to be
+                * holding the uring_lock for posting completions. Other ring
+                * types rely on the regular completion locking, which is
+                * handled while posting.
+                */
+               if (target_ctx->flags & IORING_SETUP_IOPOLL)
+                       mutex_lock(&target_ctx->uring_lock);
+               if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
+                       ret = -EOVERFLOW;
+               if (target_ctx->flags & IORING_SETUP_IOPOLL)
+                       mutex_unlock(&target_ctx->uring_lock);
+       }
 
        if (ret < 0)
                req_set_fail(req);
        io_req_queue_tw_complete(req, ret);
 }
 
-static int io_msg_ring_data(struct io_kiocb *req)
+static int io_msg_ring_data(struct io_kiocb *req, unsigned int issue_flags)
 {
        struct io_ring_ctx *target_ctx = req->file->private_data;
        struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
+       int ret;
 
        if (msg->src_fd || msg->dst_fd || msg->flags)
                return -EINVAL;
+       if (target_ctx->flags & IORING_SETUP_R_DISABLED)
+               return -EBADFD;
 
-       if (target_ctx->task_complete && current != target_ctx->submitter_task) {
-               init_task_work(&msg->tw, io_msg_tw_complete);
-               if (task_work_add(target_ctx->submitter_task, &msg->tw,
-                                 TWA_SIGNAL_NO_IPI))
-                       return -EOWNERDEAD;
-
-               atomic_or(IORING_SQ_TASKRUN, &target_ctx->rings->sq_flags);
-               return IOU_ISSUE_SKIP_COMPLETE;
-       }
-
-       if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
-               return 0;
+       if (io_msg_need_remote(target_ctx))
+               return io_msg_exec_remote(req, io_msg_tw_complete);
 
-       return -EOVERFLOW;
-}
-
-static void io_double_unlock_ctx(struct io_ring_ctx *octx,
-                                unsigned int issue_flags)
-{
-       mutex_unlock(&octx->uring_lock);
-}
-
-static int io_double_lock_ctx(struct io_ring_ctx *octx,
-                             unsigned int issue_flags)
-{
-       /*
-        * To ensure proper ordering between the two ctxs, we can only
-        * attempt a trylock on the target. If that fails and we already have
-        * the source ctx lock, punt to io-wq.
-        */
-       if (!(issue_flags & IO_URING_F_UNLOCKED)) {
-               if (!mutex_trylock(&octx->uring_lock))
+       ret = -EOVERFLOW;
+       if (target_ctx->flags & IORING_SETUP_IOPOLL) {
+               if (unlikely(io_double_lock_ctx(target_ctx, issue_flags)))
                        return -EAGAIN;
-               return 0;
+               if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
+                       ret = 0;
+               io_double_unlock_ctx(target_ctx);
+       } else {
+               if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
+                       ret = 0;
        }
-       mutex_lock(&octx->uring_lock);
-       return 0;
+       return ret;
 }
 
 static struct file *io_msg_grab_file(struct io_kiocb *req, unsigned int issue_flags)
@@ -148,7 +186,7 @@ static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flag
        if (!io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0))
                ret = -EOVERFLOW;
 out_unlock:
-       io_double_unlock_ctx(target_ctx, issue_flags);
+       io_double_unlock_ctx(target_ctx);
        return ret;
 }
 
@@ -174,6 +212,8 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
 
        if (target_ctx == ctx)
                return -EINVAL;
+       if (target_ctx->flags & IORING_SETUP_R_DISABLED)
+               return -EBADFD;
        if (!src_file) {
                src_file = io_msg_grab_file(req, issue_flags);
                if (!src_file)
@@ -182,14 +222,8 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
                req->flags |= REQ_F_NEED_CLEANUP;
        }
 
-       if (target_ctx->task_complete && current != target_ctx->submitter_task) {
-               init_task_work(&msg->tw, io_msg_tw_fd_complete);
-               if (task_work_add(target_ctx->submitter_task, &msg->tw,
-                                 TWA_SIGNAL))
-                       return -EOWNERDEAD;
-
-               return IOU_ISSUE_SKIP_COMPLETE;
-       }
+       if (io_msg_need_remote(target_ctx))
+               return io_msg_exec_remote(req, io_msg_tw_fd_complete);
        return io_msg_install_complete(req, issue_flags);
 }
 
@@ -224,7 +258,7 @@ int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags)
 
        switch (msg->cmd) {
        case IORING_MSG_DATA:
-               ret = io_msg_ring_data(req);
+               ret = io_msg_ring_data(req, issue_flags);
                break;
        case IORING_MSG_SEND_FD:
                ret = io_msg_send_fd(req, issue_flags);