Commit e6ea7ec4 authored by Caleb Sander Mateos's avatar Caleb Sander Mateos Committed by Jens Axboe
Browse files

io_uring/ublk: report error when unregister operation fails 



Indicate to userspace applications if a UBLK_IO_UNREGISTER_IO_BUF
command specifies an invalid buffer index by returning an error code.
Return -EINVAL if no buffer is registered with the given index, and
-EBUSY if the registered buffer is not a kernel bvec.

Signed-off-by: default avatarCaleb Sander Mateos <csander@purestorage.com>
Link: https://lore.kernel.org/r/20250228231432.642417-1-csander@purestorage.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 09fdd351

drivers/block/ublk_drv.c

+1 −2
Original line number Diff line number Diff line
@@ -1787,8 +1787,7 @@ static int ublk_unregister_io_buf(struct io_uring_cmd *cmd, 
				  const struct ublksrv_io_cmd *ub_cmd,

				  unsigned int issue_flags)

{

	io_buffer_unregister_bvec(cmd, ub_cmd->addr, issue_flags);

	return 0;

	return io_buffer_unregister_bvec(cmd, ub_cmd->addr, issue_flags);

}



static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,

include/linux/io_uring/cmd.h

+2 −2
Original line number Diff line number Diff line
@@ -131,7 +131,7 @@ static inline struct io_uring_cmd_data *io_uring_cmd_get_async_data(struct io_ur 
int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,

			    void (*release)(void *), unsigned int index,

			    unsigned int issue_flags);

void io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,

int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,

			      unsigned int issue_flags);



#endif /* _LINUX_IO_URING_CMD_H */

io_uring/rsrc.c

+14 −4
Original line number Diff line number Diff line
@@ -973,26 +973,36 @@ int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq, 
}

EXPORT_SYMBOL_GPL(io_buffer_register_bvec);



void io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,

int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,

			      unsigned int issue_flags)

{

	struct io_ring_ctx *ctx = cmd_to_io_kiocb(cmd)->ctx;

	struct io_rsrc_data *data = &ctx->buf_table;

	struct io_rsrc_node *node;

	int ret = 0;



	io_ring_submit_lock(ctx, issue_flags);

	if (index >= data->nr)

	if (index >= data->nr) {

		ret = -EINVAL;

		goto unlock;

	}

	index = array_index_nospec(index, data->nr);



	node = data->nodes[index];

	if (!node || !node->buf->is_kbuf)

	if (!node) {

		ret = -EINVAL;

		goto unlock;

	}

	if (!node->buf->is_kbuf) {

		ret = -EBUSY;

		goto unlock;

	}



	io_put_rsrc_node(ctx, node);

	data->nodes[index] = NULL;

unlock:

	io_ring_submit_unlock(ctx, issue_flags);

	return ret;

}

EXPORT_SYMBOL_GPL(io_buffer_unregister_bvec);