xref: /linux/io_uring/zcrx.h (revision f5437ff7299e47e76e52d37a2937a4b0f04e399f)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef IOU_ZC_RX_H
3 #define IOU_ZC_RX_H
4 
5 #include <linux/io_uring_types.h>
6 #include <linux/dma-buf.h>
7 #include <linux/socket.h>
8 #include <net/page_pool/types.h>
9 #include <net/net_trackers.h>
10 
11 #define ZCRX_SUPPORTED_REG_FLAGS	(ZCRX_REG_IMPORT | ZCRX_REG_NODEV)
12 #define ZCRX_FEATURES			(ZCRX_FEATURE_RX_PAGE_SIZE |\
13 					 ZCRX_FEATURE_EVENT)
14 #define ZCRX_EVENT_TYPE_MASK		((1U << ZCRX_EVENT_ALLOC_FAIL) |\
15 					 (1U << ZCRX_EVENT_COPY))
16 
17 struct io_zcrx_mem {
18 	unsigned long			size;
19 	bool				is_dmabuf;
20 
21 	struct page			**pages;
22 	unsigned long			nr_folios;
23 	struct sg_table			page_sg_table;
24 	unsigned long			account_pages;
25 	struct sg_table			*sgt;
26 
27 	struct dma_buf_attachment	*attach;
28 	struct dma_buf			*dmabuf;
29 };
30 
31 struct io_zcrx_area {
32 	struct net_iov_area	nia;
33 	struct io_zcrx_ifq	*ifq;
34 	atomic_t		*user_refs;
35 
36 	bool			is_mapped;
37 	u16			area_id;
38 
39 	/* freelist */
40 	u32			free_count;
41 	u32			*freelist;
42 
43 	struct io_zcrx_mem	mem;
44 };
45 
46 struct zcrx_rq_hdr {
47 	u32		head ____cacheline_aligned_in_smp;
48 	u32		tail ____cacheline_aligned_in_smp;
49 };
50 
51 struct zcrx_rq {
52 	spinlock_t			lock;
53 	struct zcrx_rq_hdr		*ring;
54 	struct io_uring_zcrx_rqe	*rqes;
55 	u32				cached_head;
56 	u32				cached_tail;
57 	u32				nr_entries;
58 };
59 
60 struct io_zcrx_ifq {
61 	/* read-protected by any of: ->pp_lock, ->alloc_lock, ->rq.lock */
62 	struct io_zcrx_area		**areas;
63 	unsigned			nr_areas;
64 
65 	unsigned			niov_shift;
66 	struct user_struct		*user;
67 	struct mm_struct		*mm_account;
68 	bool				kern_readable;
69 
70 	struct zcrx_rq			rq ____cacheline_aligned_in_smp;
71 	spinlock_t			alloc_lock ____cacheline_aligned_in_smp;
72 
73 	u32				if_rxq;
74 	struct device			*dev;
75 	struct net_device		*netdev;
76 	netdevice_tracker		netdev_tracker;
77 	refcount_t			refs;
78 	/* counts userspace facing users like io_uring */
79 	refcount_t			user_refs;
80 
81 	/*
82 	 * Page pool and net configuration lock, can be taken deeper in the
83 	 * net stack.
84 	 */
85 	struct mutex			pp_lock;
86 	struct io_mapped_region		rq_region;
87 
88 	spinlock_t			ctx_lock;
89 	struct io_ring_ctx		*master_ctx;
90 	u32				allowed_notif_mask;
91 	u32				fired_notifs;
92 	u64				notif_data;
93 	struct zcrx_stats		*notif_stats;
94 };
95 
96 #if defined(CONFIG_IO_URING_ZCRX)
97 int io_zcrx_ctrl(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_arg);
98 int io_register_zcrx(struct io_ring_ctx *ctx,
99 			 struct io_uring_zcrx_ifq_reg __user *arg);
100 void io_unregister_zcrx(struct io_ring_ctx *ctx);
101 void io_terminate_zcrx(struct io_ring_ctx *ctx);
102 int io_zcrx_recv(struct io_kiocb *req, struct io_zcrx_ifq *ifq,
103 		 struct socket *sock, unsigned int flags,
104 		 unsigned issue_flags, unsigned int *len);
105 struct io_mapped_region *io_zcrx_get_region(struct io_ring_ctx *ctx,
106 					    unsigned int id);
107 #else
io_register_zcrx(struct io_ring_ctx * ctx,struct io_uring_zcrx_ifq_reg __user * arg)108 static inline int io_register_zcrx(struct io_ring_ctx *ctx,
109 				   struct io_uring_zcrx_ifq_reg __user *arg)
110 {
111 	return -EOPNOTSUPP;
112 }
io_unregister_zcrx(struct io_ring_ctx * ctx)113 static inline void io_unregister_zcrx(struct io_ring_ctx *ctx)
114 {
115 }
io_terminate_zcrx(struct io_ring_ctx * ctx)116 static inline void io_terminate_zcrx(struct io_ring_ctx *ctx)
117 {
118 }
io_zcrx_recv(struct io_kiocb * req,struct io_zcrx_ifq * ifq,struct socket * sock,unsigned int flags,unsigned issue_flags,unsigned int * len)119 static inline int io_zcrx_recv(struct io_kiocb *req, struct io_zcrx_ifq *ifq,
120 			       struct socket *sock, unsigned int flags,
121 			       unsigned issue_flags, unsigned int *len)
122 {
123 	return -EOPNOTSUPP;
124 }
io_zcrx_get_region(struct io_ring_ctx * ctx,unsigned int id)125 static inline struct io_mapped_region *io_zcrx_get_region(struct io_ring_ctx *ctx,
126 							  unsigned int id)
127 {
128 	return NULL;
129 }
io_zcrx_ctrl(struct io_ring_ctx * ctx,void __user * arg,unsigned nr_arg)130 static inline int io_zcrx_ctrl(struct io_ring_ctx *ctx,
131 				void __user *arg, unsigned nr_arg)
132 {
133 	return -EOPNOTSUPP;
134 }
135 #endif
136 
137 int io_recvzc(struct io_kiocb *req, unsigned int issue_flags);
138 int io_recvzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
139 
140 #endif
141