xref: /linux/io_uring/rsrc.h (revision 2fe3c78a2c26dd5ee811024a1b7d6cfb4d654319)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef IOU_RSRC_H
3 #define IOU_RSRC_H
4 
5 #define IO_NODE_ALLOC_CACHE_MAX 32
6 
7 #define IO_RSRC_TAG_TABLE_SHIFT	(PAGE_SHIFT - 3)
8 #define IO_RSRC_TAG_TABLE_MAX	(1U << IO_RSRC_TAG_TABLE_SHIFT)
9 #define IO_RSRC_TAG_TABLE_MASK	(IO_RSRC_TAG_TABLE_MAX - 1)
10 
11 enum {
12 	IORING_RSRC_FILE		= 0,
13 	IORING_RSRC_BUFFER		= 1,
14 };
15 
16 struct io_rsrc_put {
17 	u64 tag;
18 	union {
19 		void *rsrc;
20 		struct file *file;
21 		struct io_mapped_ubuf *buf;
22 	};
23 };
24 
25 struct io_rsrc_data {
26 	struct io_ring_ctx		*ctx;
27 
28 	u64				**tags;
29 	unsigned int			nr;
30 	u16				rsrc_type;
31 	bool				quiesce;
32 };
33 
34 struct io_rsrc_node {
35 	struct io_ring_ctx		*ctx;
36 	int				refs;
37 	bool				empty;
38 	u16				type;
39 	struct list_head		node;
40 	struct io_rsrc_put		item;
41 };
42 
43 struct io_mapped_ubuf {
44 	u64		ubuf;
45 	u64		ubuf_end;
46 	unsigned int	nr_bvecs;
47 	unsigned int    folio_shift;
48 	unsigned long	acct_pages;
49 	unsigned long   folio_mask;
50 	refcount_t	refs;
51 	struct bio_vec	bvec[] __counted_by(nr_bvecs);
52 };
53 
54 struct io_imu_folio_data {
55 	/* Head folio can be partially included in the fixed buf */
56 	unsigned int	nr_pages_head;
57 	/* For non-head/tail folios, has to be fully included */
58 	unsigned int	nr_pages_mid;
59 	unsigned int	folio_shift;
60 };
61 
62 void io_rsrc_node_ref_zero(struct io_rsrc_node *node);
63 void io_rsrc_node_destroy(struct io_ring_ctx *ctx, struct io_rsrc_node *ref_node);
64 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx);
65 int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, void *rsrc);
66 
67 int io_import_fixed(int ddir, struct iov_iter *iter,
68 			   struct io_mapped_ubuf *imu,
69 			   u64 buf_addr, size_t len);
70 
71 int io_register_copy_buffers(struct io_ring_ctx *ctx, void __user *arg);
72 void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
73 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
74 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
75 			    unsigned int nr_args, u64 __user *tags);
76 void __io_sqe_files_unregister(struct io_ring_ctx *ctx);
77 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
78 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
79 			  unsigned nr_args, u64 __user *tags);
80 
81 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
82 			     unsigned nr_args);
83 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
84 			    unsigned size, unsigned type);
85 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
86 			unsigned int size, unsigned int type);
87 
88 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
89 {
90 	lockdep_assert_held(&ctx->uring_lock);
91 
92 	if (node && !--node->refs)
93 		io_rsrc_node_ref_zero(node);
94 }
95 
96 static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx,
97 				       struct io_rsrc_node *node)
98 {
99 	node->refs++;
100 }
101 
102 static inline void __io_req_set_rsrc_node(struct io_kiocb *req,
103 					  struct io_ring_ctx *ctx)
104 {
105 	lockdep_assert_held(&ctx->uring_lock);
106 	req->rsrc_node = ctx->rsrc_node;
107 	io_charge_rsrc_node(ctx, ctx->rsrc_node);
108 }
109 
110 static inline void io_req_set_rsrc_node(struct io_kiocb *req,
111 					struct io_ring_ctx *ctx,
112 					unsigned int issue_flags)
113 {
114 	if (!req->rsrc_node) {
115 		io_ring_submit_lock(ctx, issue_flags);
116 		__io_req_set_rsrc_node(req, ctx);
117 		io_ring_submit_unlock(ctx, issue_flags);
118 	}
119 }
120 
121 static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
122 {
123 	unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
124 	unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
125 
126 	return &data->tags[table_idx][off];
127 }
128 
129 static inline int io_rsrc_init(struct io_ring_ctx *ctx)
130 {
131 	ctx->rsrc_node = io_rsrc_node_alloc(ctx);
132 	return ctx->rsrc_node ? 0 : -ENOMEM;
133 }
134 
135 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
136 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
137 
138 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
139 
140 static inline void __io_unaccount_mem(struct user_struct *user,
141 				      unsigned long nr_pages)
142 {
143 	atomic_long_sub(nr_pages, &user->locked_vm);
144 }
145 
146 #endif
147