io_uring: add support for IORING_ASYNC_CANCEL_ANY

Rather than match on a specific key, be it user_data or file, allow
canceling any request that we can lookup. Works like
IORING_ASYNC_CANCEL_ALL in that it cancels multiple requests, but it
doesn't key off user_data or the file.

Can't be set with IORING_ASYNC_CANCEL_FD, as that's a key selector.
Only one may be used at the time.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20220418164402.75259-6-axboe@kernel.dk
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index cf0d543..03134ec 100644 (file)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6348,7 +6348,8 @@ static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
 
                list = &ctx->cancel_hash[i];
                hlist_for_each_entry(req, list, hash_node) {
-                       if (req->file != cd->file)
+                       if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
+                           req->file != cd->file)
                                continue;
                        if (cd->seq == req->work.cancel_seq)
                                continue;
@@ -6374,7 +6375,7 @@ static int io_poll_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
 {
        struct io_kiocb *req;
 
-       if (cd->flags & IORING_ASYNC_CANCEL_FD)
+       if (cd->flags & (IORING_ASYNC_CANCEL_FD|IORING_ASYNC_CANCEL_ANY))
                req = io_poll_file_find(ctx, cd);
        else
                req = io_poll_find(ctx, false, cd);
@@ -6543,9 +6544,10 @@ static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
        bool found = false;
 
        list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
-               if (cd->data != req->cqe.user_data)
+               if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
+                   cd->data != req->cqe.user_data)
                        continue;
-               if (cd->flags & IORING_ASYNC_CANCEL_ALL) {
+               if (cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY)) {
                        if (cd->seq == req->work.cancel_seq)
                                continue;
                        req->work.cancel_seq = cd->seq;
@@ -6827,14 +6829,16 @@ static bool io_cancel_cb(struct io_wq_work *work, void *data)
 
        if (req->ctx != cd->ctx)
                return false;
-       if (cd->flags & IORING_ASYNC_CANCEL_FD) {
+       if (cd->flags & IORING_ASYNC_CANCEL_ANY) {
+               ;
+       } else if (cd->flags & IORING_ASYNC_CANCEL_FD) {
                if (req->file != cd->file)
                        return false;
        } else {
                if (req->cqe.user_data != cd->data)
                        return false;
        }
-       if (cd->flags & IORING_ASYNC_CANCEL_ALL) {
+       if (cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY)) {
                if (cd->seq == req->work.cancel_seq)
                        return false;
                req->work.cancel_seq = cd->seq;
@@ -6847,12 +6851,13 @@ static int io_async_cancel_one(struct io_uring_task *tctx,
 {
        enum io_wq_cancel cancel_ret;
        int ret = 0;
+       bool all;
 
        if (!tctx || !tctx->io_wq)
                return -ENOENT;
 
-       cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, cd,
-                                       cd->flags & IORING_ASYNC_CANCEL_ALL);
+       all = cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY);
+       cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, cd, all);
        switch (cancel_ret) {
        case IO_WQ_CANCEL_OK:
                ret = 0;
@@ -6894,6 +6899,9 @@ out:
        return ret;
 }
 
+#define CANCEL_FLAGS   (IORING_ASYNC_CANCEL_ALL | IORING_ASYNC_CANCEL_FD | \
+                        IORING_ASYNC_CANCEL_ANY)
+
 static int io_async_cancel_prep(struct io_kiocb *req,
                                const struct io_uring_sqe *sqe)
 {
@@ -6906,10 +6914,13 @@ static int io_async_cancel_prep(struct io_kiocb *req,
 
        req->cancel.addr = READ_ONCE(sqe->addr);
        req->cancel.flags = READ_ONCE(sqe->cancel_flags);
-       if (req->cancel.flags & ~(IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_FD))
+       if (req->cancel.flags & ~CANCEL_FLAGS)
                return -EINVAL;
-       if (req->cancel.flags & IORING_ASYNC_CANCEL_FD)
+       if (req->cancel.flags & IORING_ASYNC_CANCEL_FD) {
+               if (req->cancel.flags & IORING_ASYNC_CANCEL_ANY)
+                       return -EINVAL;
                req->cancel.fd = READ_ONCE(sqe->fd);
+       }
 
        return 0;
 }
@@ -6917,7 +6928,7 @@ static int io_async_cancel_prep(struct io_kiocb *req,
 static int __io_async_cancel(struct io_cancel_data *cd, struct io_kiocb *req,
                             unsigned int issue_flags)
 {
-       bool cancel_all = cd->flags & IORING_ASYNC_CANCEL_ALL;
+       bool all = cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY);
        struct io_ring_ctx *ctx = cd->ctx;
        struct io_tctx_node *node;
        int ret, nr = 0;
@@ -6926,7 +6937,7 @@ static int __io_async_cancel(struct io_cancel_data *cd, struct io_kiocb *req,
                ret = io_try_cancel(req, cd);
                if (ret == -ENOENT)
                        break;
-               if (!cancel_all)
+               if (!all)
                        return ret;
                nr++;
        } while (1);
@@ -6939,13 +6950,13 @@ static int __io_async_cancel(struct io_cancel_data *cd, struct io_kiocb *req,
 
                ret = io_async_cancel_one(tctx, cd);
                if (ret != -ENOENT) {
-                       if (!cancel_all)
+                       if (!all)
                                break;
                        nr++;
                }
        }
        io_ring_submit_unlock(ctx, issue_flags);
-       return cancel_all ? nr : ret;
+       return all ? nr : ret;
 }
 
 static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index cc7fe82..980d82e 100644 (file)
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -193,9 +193,11 @@ enum {
  * IORING_ASYNC_CANCEL_ALL     Cancel all requests that match the given key
  * IORING_ASYNC_CANCEL_FD      Key off 'fd' for cancelation rather than the
  *                             request 'user_data'
+ * IORING_ASYNC_CANCEL_ANY     Match any request
  */
 #define IORING_ASYNC_CANCEL_ALL        (1U << 0)
 #define IORING_ASYNC_CANCEL_FD (1U << 1)
+#define IORING_ASYNC_CANCEL_ANY        (1U << 2)
 
 /*
  * IO completion data structure (Completion Queue Entry)