io_uring: temporarily disable registered waits

Disable wait argument registration as it'll be replaced with a more
generic feature. We'll still need IORING_ENTER_EXT_ARG_REG parsing
in a few commits so leave it be.

Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/70b1d1d218c41ba77a76d1789c8641dab0b0563e.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>

diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 072e65e931053336f0fcc99e4b4723babcd33fdb..52a5da99a2050e1813a1b4ee3710e901c6b41ab7 100644 (file)
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -330,14 +330,6 @@ struct io_ring_ctx {
                atomic_t                cq_wait_nr;
                atomic_t                cq_timeouts;
                struct wait_queue_head  cq_wait;
-
-               /*
-                * If registered with IORING_REGISTER_CQWAIT_REG, a single
-                * page holds N entries, mapped in cq_wait_arg. cq_wait_index
-                * is the maximum allowable index.
-                */
-               struct io_uring_reg_wait        *cq_wait_arg;
-               unsigned char                   cq_wait_index;
        } ____cacheline_aligned_in_smp;
 
        /* timeouts */
@@ -431,8 +423,6 @@ struct io_ring_ctx {
        unsigned short                  n_sqe_pages;
        struct page                     **ring_pages;
        struct page                     **sqe_pages;
-
-       struct page                     **cq_wait_page;
 };
 
 struct io_tw_state {

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 5d08435b95a8aaab317edb248c882f7384b5b254..132f5db3d4e83d107a59640b4a218ea3ed2ab1dd 100644 (file)
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -627,9 +627,6 @@ enum io_uring_register_op {
        /* resize CQ ring */
        IORING_REGISTER_RESIZE_RINGS            = 33,
 
-       /* register fixed io_uring_reg_wait arguments */
-       IORING_REGISTER_CQWAIT_REG              = 34,
-
        /* this goes last */
        IORING_REGISTER_LAST,
 

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 464a70bde7e67c83471c2b343300bec8891ec8d2..286b7bb73978fe5ba86ab853a37b9be018f4416b 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2709,7 +2709,6 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
        io_alloc_cache_free(&ctx->msg_cache, io_msg_cache_free);
        io_futex_cache_free(ctx);
        io_destroy_buffers(ctx);
-       io_unregister_cqwait_reg(ctx);
        mutex_unlock(&ctx->uring_lock);
        if (ctx->sq_creds)
                put_cred(ctx->sq_creds);
@@ -3195,15 +3194,6 @@ void __io_uring_cancel(bool cancel_all)
 static struct io_uring_reg_wait *io_get_ext_arg_reg(struct io_ring_ctx *ctx,
                        const struct io_uring_getevents_arg __user *uarg)
 {
-       struct io_uring_reg_wait *arg = READ_ONCE(ctx->cq_wait_arg);
-
-       if (arg) {
-               unsigned int index = (unsigned int) (uintptr_t) uarg;
-
-               if (index <= ctx->cq_wait_index)
-                       return arg + index;
-       }
-
        return ERR_PTR(-EFAULT);
 }
 

diff --git a/io_uring/register.c b/io_uring/register.c
index 45edfc57963a27cb6d257f3fa66d4ca63fac69d1..3c5a3cfb186bb7919f9314a6828c769bd63d79a2 100644 (file)
--- a/io_uring/register.c
+++ b/io_uring/register.c
@@ -570,82 +570,6 @@ out:
        return ret;
 }
 
-void io_unregister_cqwait_reg(struct io_ring_ctx *ctx)
-{
-       unsigned short npages = 1;
-
-       if (!ctx->cq_wait_page)
-               return;
-
-       io_pages_unmap(ctx->cq_wait_arg, &ctx->cq_wait_page, &npages, true);
-       ctx->cq_wait_arg = NULL;
-       if (ctx->user)
-               __io_unaccount_mem(ctx->user, 1);
-}
-
-/*
- * Register a page holding N entries of struct io_uring_reg_wait, which can
- * be used via io_uring_enter(2) if IORING_GETEVENTS_EXT_ARG_REG is set.
- * If that is set with IORING_GETEVENTS_EXT_ARG, then instead of passing
- * in a pointer for a struct io_uring_getevents_arg, an index into this
- * registered array is passed, avoiding two (arg + timeout) copies per
- * invocation.
- */
-static int io_register_cqwait_reg(struct io_ring_ctx *ctx, void __user *uarg)
-{
-       struct io_uring_cqwait_reg_arg arg;
-       struct io_uring_reg_wait *reg;
-       struct page **pages;
-       unsigned long len;
-       int nr_pages, poff;
-       int ret;
-
-       if (ctx->cq_wait_page || ctx->cq_wait_arg)
-               return -EBUSY;
-       if (copy_from_user(&arg, uarg, sizeof(arg)))
-               return -EFAULT;
-       if (!arg.nr_entries || arg.flags)
-               return -EINVAL;
-       if (arg.struct_size != sizeof(*reg))
-               return -EINVAL;
-       if (check_mul_overflow(arg.struct_size, arg.nr_entries, &len))
-               return -EOVERFLOW;
-       if (len > PAGE_SIZE)
-               return -EINVAL;
-       /* offset + len must fit within a page, and must be reg_wait aligned */
-       poff = arg.user_addr & ~PAGE_MASK;
-       if (len + poff > PAGE_SIZE)
-               return -EINVAL;
-       if (poff % arg.struct_size)
-               return -EINVAL;
-
-       pages = io_pin_pages(arg.user_addr, len, &nr_pages);
-       if (IS_ERR(pages))
-               return PTR_ERR(pages);
-       ret = -EINVAL;
-       if (nr_pages != 1)
-               goto out_free;
-       if (ctx->user) {
-               ret = __io_account_mem(ctx->user, 1);
-               if (ret)
-                       goto out_free;
-       }
-
-       reg = vmap(pages, 1, VM_MAP, PAGE_KERNEL);
-       if (reg) {
-               ctx->cq_wait_index = arg.nr_entries - 1;
-               WRITE_ONCE(ctx->cq_wait_page, pages);
-               WRITE_ONCE(ctx->cq_wait_arg, (void *) reg + poff);
-               return 0;
-       }
-       ret = -ENOMEM;
-       if (ctx->user)
-               __io_unaccount_mem(ctx->user, 1);
-out_free:
-       io_pages_free(&pages, nr_pages);
-       return ret;
-}
-
 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
                               void __user *arg, unsigned nr_args)
        __releases(ctx->uring_lock)
@@ -840,12 +764,6 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
                        break;
                ret = io_register_resize_rings(ctx, arg);
                break;
-       case IORING_REGISTER_CQWAIT_REG:
-               ret = -EINVAL;
-               if (!arg || nr_args != 1)
-                       break;
-               ret = io_register_cqwait_reg(ctx, arg);
-               break;
        default:
                ret = -EINVAL;
                break;

diff --git a/io_uring/register.h b/io_uring/register.h
index 3e935e8fa4b2e25c4fd1e093a9f056e2d1b1cc6f..a5f39d5ef9e0e4588134c6b50ae4905430f8e1d1 100644 (file)
--- a/io_uring/register.h
+++ b/io_uring/register.h
@@ -5,6 +5,5 @@
 int io_eventfd_unregister(struct io_ring_ctx *ctx);
 int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id);
 struct file *io_uring_register_get_file(unsigned int fd, bool registered);
-void io_unregister_cqwait_reg(struct io_ring_ctx *ctx);
 
 #endif