Commit 4b851d20 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring/memmap: add IO_REGION_F_SINGLE_REF 



Kernel allocated compound pages will have just one reference for the
entire page array, add a flag telling io_free_region about that.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/a7abfa7535e9728d5fcade29a1ea1605ec2c04ce.1732886067.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent a90558b3

io_uring/memmap.c

+10 −2
Original line number Diff line number Diff line
@@ -207,15 +207,23 @@ enum { 
	IO_REGION_F_VMAP			= 1,

	/* memory is provided by user and pinned by the kernel */

	IO_REGION_F_USER_PROVIDED		= 2,

	/* only the first page in the array is ref'ed */

	IO_REGION_F_SINGLE_REF			= 4,

};



void io_free_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr)

{

	if (mr->pages) {

		long nr_refs = mr->nr_pages;



		if (mr->flags & IO_REGION_F_SINGLE_REF)

			nr_refs = 1;



		if (mr->flags & IO_REGION_F_USER_PROVIDED)

			unpin_user_pages(mr->pages, mr->nr_pages);

			unpin_user_pages(mr->pages, nr_refs);

		else

			release_pages(mr->pages, mr->nr_pages);

			release_pages(mr->pages, nr_refs);



		kvfree(mr->pages);

	}

	if ((mr->flags & IO_REGION_F_VMAP) && mr->ptr)