// SPDX-License-Identifier: GPL-2.0#ifndef IOU_KBUF_H#define IOU_KBUF_H #include <uapi/linux/io_uring.h>#include <linux/io_uring_types.h> enum {	/* ring mapped provided buffers */	IOBL_BUF_RING	= 1,	/* buffers are consumed incrementally rather than always fully */	IOBL_INC	= 2,}; struct io_buffer_list {	/*	 * If the IOBL_BUF_RING flag is set, then buf_ring is used. If not, then	 * these are classic provided buffers and ->buf_list is used.	 */	union {		struct list_head buf_list;		struct io_uring_buf_ring *buf_ring;	};	/* count of classic/legacy buffers in buffer list */	int nbufs; 	__u16 bgid; 	/* below is for ring provided buffers */	__u16 head;	__u16 mask; 	__u16 flags; 	/*	 * minimum required amount to be left to reuse an incrementally	 * consumed buffer. If less than this is left at consumption time,	 * buffer is done and head is incremented to the next buffer.	 */	__u32 min_left_sub_one; 	struct io_mapped_region region;}; struct io_buffer {	struct list_head list;	__u64 addr;	__u32 len;	__u16 bid;	__u16 bgid;}; enum {	/* can alloc a bigger vec */	KBUF_MODE_EXPAND	= 1,	/* if bigger vec allocated, free old one */	KBUF_MODE_FREE		= 2,}; struct buf_sel_arg {	struct iovec *iovs;	size_t out_len;	size_t max_len;	unsigned short nr_iovs;	unsigned short mode;	unsigned short buf_group;	unsigned short partial_map;}; struct io_br_sel io_buffer_select(struct io_kiocb *req, size_t *len,				  unsigned buf_group, unsigned int issue_flags);int io_buffers_select(struct io_kiocb *req, struct buf_sel_arg *arg,		      struct io_br_sel *sel, unsigned int issue_flags);int io_buffers_peek(struct io_kiocb *req, struct buf_sel_arg *arg,		    struct io_br_sel *sel);void io_destroy_buffers(struct io_ring_ctx *ctx); int io_remove_buffers_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);int io_provide_buffers_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);int io_manage_buffers_legacy(struct io_kiocb *req, unsigned int issue_flags); int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg);int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg);int io_register_pbuf_status(struct io_ring_ctx *ctx, void __user *arg); bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags);void io_kbuf_drop_legacy(struct io_kiocb *req); unsigned int __io_put_kbufs(struct io_kiocb *req, struct io_buffer_list *bl,			    int len, int nbufs);bool io_kbuf_commit(struct io_kiocb *req,		    struct io_buffer_list *bl, int len, int nr); struct io_mapped_region *io_pbuf_get_region(struct io_ring_ctx *ctx,					    unsigned int bgid); static inline bool io_kbuf_recycle_ring(struct io_kiocb *req,					struct io_buffer_list *bl){	if (bl) {		req->flags &= ~(REQ_F_BUFFER_RING|REQ_F_BUFFERS_COMMIT);		return true;	}	return false;} static inline bool io_do_buffer_select(struct io_kiocb *req){	if (!(req->flags & REQ_F_BUFFER_SELECT))		return false;	return !(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING));} static inline bool io_kbuf_recycle(struct io_kiocb *req, struct io_buffer_list *bl,				   unsigned issue_flags){	if (req->flags & REQ_F_BL_NO_RECYCLE)		return false;	if (req->flags & REQ_F_BUFFER_RING)		return io_kbuf_recycle_ring(req, bl);	if (req->flags & REQ_F_BUFFER_SELECTED)		return io_kbuf_recycle_legacy(req, issue_flags);	return false;} static inline unsigned int io_put_kbuf(struct io_kiocb *req, int len,				       struct io_buffer_list *bl){	if (!(req->flags & (REQ_F_BUFFER_RING | REQ_F_BUFFER_SELECTED)))		return 0;	return __io_put_kbufs(req, bl, len, 1);} static inline unsigned int io_put_kbufs(struct io_kiocb *req, int len,					struct io_buffer_list *bl, int nbufs){	if (!(req->flags & (REQ_F_BUFFER_RING | REQ_F_BUFFER_SELECTED)))		return 0;	return __io_put_kbufs(req, bl, len, nbufs);}#endif