xref: /linux/io_uring/zcrx.h (revision 7c713dd0078651d040a0251eab6e29e3c2e4ee11)
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 
14 struct io_zcrx_mem {
15 	unsigned long			size;
16 	bool				is_dmabuf;
17 
18 	struct page			**pages;
19 	unsigned long			nr_folios;
20 	struct sg_table			page_sg_table;
21 	unsigned long			account_pages;
22 	struct sg_table			*sgt;
23 
24 	struct dma_buf_attachment	*attach;
25 	struct dma_buf			*dmabuf;
26 };
27 
28 struct io_zcrx_area {
29 	struct net_iov_area	nia;
30 	struct io_zcrx_ifq	*ifq;
31 	atomic_t		*user_refs;
32 
33 	bool			is_mapped;
34 	u16			area_id;
35 
36 	/* freelist */
37 	spinlock_t		freelist_lock ____cacheline_aligned_in_smp;
38 	u32			free_count;
39 	u32			*freelist;
40 
41 	struct io_zcrx_mem	mem;
42 };
43 
44 struct zcrx_rq {
45 	spinlock_t			lock;
46 	struct io_uring			*ring;
47 	struct io_uring_zcrx_rqe	*rqes;
48 	u32				cached_head;
49 	u32				nr_entries;
50 };
51 
52 struct io_zcrx_ifq {
53 	struct io_zcrx_area		*area;
54 	unsigned			niov_shift;
55 	struct user_struct		*user;
56 	struct mm_struct		*mm_account;
57 	bool				kern_readable;
58 
59 	struct zcrx_rq			rq ____cacheline_aligned_in_smp;
60 
61 	u32				if_rxq;
62 	struct device			*dev;
63 	struct net_device		*netdev;
64 	netdevice_tracker		netdev_tracker;
65 	refcount_t			refs;
66 	/* counts userspace facing users like io_uring */
67 	refcount_t			user_refs;
68 
69 	/*
70 	 * Page pool and net configuration lock, can be taken deeper in the
71 	 * net stack.
72 	 */
73 	struct mutex			pp_lock;
74 	struct io_mapped_region		rq_region;
75 };
76 
77 #if defined(CONFIG_IO_URING_ZCRX)
78 int io_zcrx_ctrl(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_arg);
79 int io_register_zcrx(struct io_ring_ctx *ctx,
80 			 struct io_uring_zcrx_ifq_reg __user *arg);
81 void io_unregister_zcrx(struct io_ring_ctx *ctx);
82 void io_terminate_zcrx(struct io_ring_ctx *ctx);
83 int io_zcrx_recv(struct io_kiocb *req, struct io_zcrx_ifq *ifq,
84 		 struct socket *sock, unsigned int flags,
85 		 unsigned issue_flags, unsigned int *len);
86 struct io_mapped_region *io_zcrx_get_region(struct io_ring_ctx *ctx,
87 					    unsigned int id);
88 #else
89 static inline int io_register_zcrx(struct io_ring_ctx *ctx,
90 				   struct io_uring_zcrx_ifq_reg __user *arg)
91 {
92 	return -EOPNOTSUPP;
93 }
94 static inline void io_unregister_zcrx(struct io_ring_ctx *ctx)
95 {
96 }
97 static inline void io_terminate_zcrx(struct io_ring_ctx *ctx)
98 {
99 }
100 static inline int io_zcrx_recv(struct io_kiocb *req, struct io_zcrx_ifq *ifq,
101 			       struct socket *sock, unsigned int flags,
102 			       unsigned issue_flags, unsigned int *len)
103 {
104 	return -EOPNOTSUPP;
105 }
106 static inline struct io_mapped_region *io_zcrx_get_region(struct io_ring_ctx *ctx,
107 							  unsigned int id)
108 {
109 	return NULL;
110 }
111 static inline int io_zcrx_ctrl(struct io_ring_ctx *ctx,
112 				void __user *arg, unsigned nr_arg)
113 {
114 	return -EOPNOTSUPP;
115 }
116 #endif
117 
118 int io_recvzc(struct io_kiocb *req, unsigned int issue_flags);
119 int io_recvzc_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
120 
121 #endif
122