1 // SPDX-License-Identifier: GPL-2.0 2 #ifndef IOU_KBUF_H 3 #define IOU_KBUF_H 4 5 #include <uapi/linux/io_uring.h> 6 #include <linux/io_uring_types.h> 7 8 enum { 9 /* ring mapped provided buffers */ 10 IOBL_BUF_RING = 1, 11 /* buffers are consumed incrementally rather than always fully */ 12 IOBL_INC = 2, 13 }; 14 15 struct io_buffer_list { 16 /* 17 * If the IOBL_BUF_RING flag is set, then buf_ring is used. If not, then 18 * these are classic provided buffers and ->buf_list is used. 19 */ 20 union { 21 struct list_head buf_list; 22 struct io_uring_buf_ring *buf_ring; 23 }; 24 /* count of classic/legacy buffers in buffer list */ 25 int nbufs; 26 27 __u16 bgid; 28 29 /* below is for ring provided buffers */ 30 __u16 head; 31 __u16 mask; 32 33 __u16 flags; 34 35 /* 36 * minimum required amount to be left to reuse an incrementally 37 * consumed buffer. If less than this is left at consumption time, 38 * buffer is done and head is incremented to the next buffer. 39 */ 40 __u32 min_left_sub_one; 41 42 struct io_mapped_region region; 43 }; 44 45 struct io_buffer { 46 struct list_head list; 47 __u64 addr; 48 __u32 len; 49 __u16 bid; 50 __u16 bgid; 51 }; 52 53 enum { 54 /* can alloc a bigger vec */ 55 KBUF_MODE_EXPAND = 1, 56 /* if bigger vec allocated, free old one */ 57 KBUF_MODE_FREE = 2, 58 }; 59 60 struct buf_sel_arg { 61 struct iovec *iovs; 62 size_t out_len; 63 size_t max_len; 64 unsigned short nr_iovs; 65 unsigned short mode; 66 unsigned short buf_group; 67 unsigned short partial_map; 68 }; 69 70 struct io_br_sel io_buffer_select(struct io_kiocb *req, size_t *len, 71 unsigned buf_group, unsigned int issue_flags); 72 int io_buffers_select(struct io_kiocb *req, struct buf_sel_arg *arg, 73 struct io_br_sel *sel, unsigned int issue_flags); 74 int io_buffers_peek(struct io_kiocb *req, struct buf_sel_arg *arg, 75 struct io_br_sel *sel); 76 void io_destroy_buffers(struct io_ring_ctx *ctx); 77 78 int io_remove_buffers_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); 79 int io_provide_buffers_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe); 80 int io_manage_buffers_legacy(struct io_kiocb *req, unsigned int issue_flags); 81 82 int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg); 83 int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg); 84 int io_register_pbuf_status(struct io_ring_ctx *ctx, void __user *arg); 85 86 bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags); 87 void io_kbuf_drop_legacy(struct io_kiocb *req); 88 89 unsigned int __io_put_kbufs(struct io_kiocb *req, struct io_buffer_list *bl, 90 int len, int nbufs); 91 bool io_kbuf_commit(struct io_kiocb *req, 92 struct io_buffer_list *bl, int len, int nr); 93 94 struct io_mapped_region *io_pbuf_get_region(struct io_ring_ctx *ctx, 95 unsigned int bgid); 96 97 static inline bool io_kbuf_recycle_ring(struct io_kiocb *req, 98 struct io_buffer_list *bl) 99 { 100 if (bl) { 101 req->flags &= ~(REQ_F_BUFFER_RING|REQ_F_BUFFERS_COMMIT); 102 return true; 103 } 104 return false; 105 } 106 107 static inline bool io_do_buffer_select(struct io_kiocb *req) 108 { 109 if (!(req->flags & REQ_F_BUFFER_SELECT)) 110 return false; 111 return !(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)); 112 } 113 114 static inline bool io_kbuf_recycle(struct io_kiocb *req, struct io_buffer_list *bl, 115 unsigned issue_flags) 116 { 117 if (req->flags & REQ_F_BL_NO_RECYCLE) 118 return false; 119 if (req->flags & REQ_F_BUFFER_RING) 120 return io_kbuf_recycle_ring(req, bl); 121 if (req->flags & REQ_F_BUFFER_SELECTED) 122 return io_kbuf_recycle_legacy(req, issue_flags); 123 return false; 124 } 125 126 static inline unsigned int io_put_kbuf(struct io_kiocb *req, int len, 127 struct io_buffer_list *bl) 128 { 129 if (!(req->flags & (REQ_F_BUFFER_RING | REQ_F_BUFFER_SELECTED))) 130 return 0; 131 return __io_put_kbufs(req, bl, len, 1); 132 } 133 134 static inline unsigned int io_put_kbufs(struct io_kiocb *req, int len, 135 struct io_buffer_list *bl, int nbufs) 136 { 137 if (!(req->flags & (REQ_F_BUFFER_RING | REQ_F_BUFFER_SELECTED))) 138 return 0; 139 return __io_put_kbufs(req, bl, len, nbufs); 140 } 141 #endif 142