Commit fc5f22a6 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
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io_uring/memmap: account memory before pinning 



Move memory accounting before page pinning. It shouldn't even try to pin
pages if it's not allowed, and accounting is also relatively
inexpensive. It also give a better code structure as we do generic
accounting and then can branch for different mapping types.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1e242b8038411a222e8b269d35e021fa5015289f.1732886067.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 16375af3

io_uring/memmap.c

+11 −6
Original line number Diff line number Diff line
@@ -252,17 +252,21 @@ int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, 
	if (check_add_overflow(reg->user_addr, reg->size, &end))

		return -EOVERFLOW;



	pages = io_pin_pages(reg->user_addr, reg->size, &nr_pages);

	if (IS_ERR(pages))

		return PTR_ERR(pages);



	nr_pages = reg->size >> PAGE_SHIFT;

	if (ctx->user) {

		ret = __io_account_mem(ctx->user, nr_pages);

		if (ret)

			goto out_free;

			return ret;

		pages_accounted = nr_pages;

	}



	pages = io_pin_pages(reg->user_addr, reg->size, &nr_pages);

	if (IS_ERR(pages)) {

		ret = PTR_ERR(pages);

		pages = NULL;

		goto out_free;

	}



	vptr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);

	if (!vptr) {

		ret = -ENOMEM;
@@ -277,6 +281,7 @@ int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, 
out_free:

	if (pages_accounted)

		__io_unaccount_mem(ctx->user, pages_accounted);

	if (pages)

		io_pages_free(&pages, nr_pages);

	return ret;

}