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 <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/70b1d1d218c41ba77a76d1789c8641dab0b0563e.1731689588.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2024-11-15 16:54:40 +00:00 committed by Jens Axboe
parent 3730aebbda
commit 83e041522e
5 changed files with 0 additions and 106 deletions

View File

@ -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 {

View File

@ -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,

View File

@ -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);
}

View File

@ -570,82 +570,6 @@ static int io_register_resize_rings(struct io_ring_ctx *ctx, void __user *arg)
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;

View File

@ -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