Commit 25a2c188 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring/kbuf: add buffer_list->is_mapped member 



Rather than rely on checking buffer_list->buf_pages or ->buf_nr_pages,
add a separate member that tracks if this is a ring mapped provided
buffer list or not.

Acked-by: default avatarHelge Deller <deller@gmx.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent ba56b632

io_uring/kbuf.c

+8 −6
Original line number Diff line number Diff line
@@ -179,7 +179,7 @@ void __user *io_buffer_select(struct io_kiocb *req, size_t *len, 


	bl = io_buffer_get_list(ctx, req->buf_index);

	if (likely(bl)) {

		if (bl->buf_nr_pages)

		if (bl->is_mapped)

			ret = io_ring_buffer_select(req, len, bl, issue_flags);

		else

			ret = io_provided_buffer_select(req, len, bl);
@@ -214,7 +214,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx, 
	if (!nbufs)

		return 0;



	if (bl->buf_nr_pages) {

	if (bl->is_mapped && bl->buf_nr_pages) {

		int j;



		i = bl->buf_ring->tail - bl->head;
@@ -225,6 +225,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx, 
		bl->buf_nr_pages = 0;

		/* make sure it's seen as empty */

		INIT_LIST_HEAD(&bl->buf_list);

		bl->is_mapped = 0;

		return i;

	}
@@ -303,7 +304,7 @@ int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags) 
	if (bl) {

		ret = -EINVAL;

		/* can't use provide/remove buffers command on mapped buffers */

		if (!bl->buf_nr_pages)

		if (!bl->is_mapped)

			ret = __io_remove_buffers(ctx, bl, p->nbufs);

	}

	io_ring_submit_unlock(ctx, issue_flags);
@@ -448,7 +449,7 @@ int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags) 
		}

	}

	/* can't add buffers via this command for a mapped buffer ring */

	if (bl->buf_nr_pages) {

	if (bl->is_mapped) {

		ret = -EINVAL;

		goto err;

	}
@@ -480,6 +481,7 @@ static int io_pin_pbuf_ring(struct io_uring_buf_reg *reg, 
	bl->buf_pages = pages;

	bl->buf_nr_pages = nr_pages;

	bl->buf_ring = br;

	bl->is_mapped = 1;

	return 0;

}
@@ -514,7 +516,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) 
	bl = io_buffer_get_list(ctx, reg.bgid);

	if (bl) {

		/* if mapped buffer ring OR classic exists, don't allow */

		if (bl->buf_nr_pages || !list_empty(&bl->buf_list))

		if (bl->is_mapped || !list_empty(&bl->buf_list))

			return -EEXIST;

	} else {

		free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL);
@@ -548,7 +550,7 @@ int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) 
	bl = io_buffer_get_list(ctx, reg.bgid);

	if (!bl)

		return -ENOENT;

	if (!bl->buf_nr_pages)

	if (!bl->is_mapped)

		return -EINVAL;



	__io_remove_buffers(ctx, bl, -1U);

io_uring/kbuf.h

+3 −0
Original line number Diff line number Diff line
@@ -23,6 +23,9 @@ struct io_buffer_list { 
	__u16 nr_entries;

	__u16 head;

	__u16 mask;



	/* ring mapped provided buffers */

	__u8 is_mapped;

};



struct io_buffer {