xref: /linux/io_uring/rsrc.h (revision ca76b56a2a2acf9875e5cad68612085f25b463bb)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef IOU_RSRC_H
3 #define IOU_RSRC_H
4 
5 #include <linux/io_uring_types.h>
6 #include <linux/lockdep.h>
7 
8 #define IO_VEC_CACHE_SOFT_CAP		256
9 
10 enum {
11 	IORING_RSRC_FILE		= 0,
12 	IORING_RSRC_BUFFER		= 1,
13 };
14 
15 struct io_rsrc_node {
16 	unsigned char			type;
17 	int				refs;
18 
19 	u64 tag;
20 	union {
21 		unsigned long file_ptr;
22 		struct io_mapped_ubuf *buf;
23 	};
24 };
25 
26 enum {
27 	IO_IMU_DEST	= 1 << ITER_DEST,
28 	IO_IMU_SOURCE	= 1 << ITER_SOURCE,
29 };
30 
31 enum {
32 	IO_REGBUF_F_KBUF		= 1,
33 };
34 
35 struct io_mapped_ubuf {
36 	u64		ubuf;
37 	size_t		len;
38 	unsigned int	nr_bvecs;
39 	unsigned int    folio_shift;
40 	refcount_t	refs;
41 	u8		flags;
42 	u8		dir;
43 	void		(*release)(void *);
44 	void		*priv;
45 	struct bio_vec	bvec[] __counted_by(nr_bvecs);
46 };
47 
48 struct io_imu_folio_data {
49 	/* Head folio can be partially included in the fixed buf */
50 	unsigned int	nr_pages_head;
51 	/* For non-head/tail folios, has to be fully included */
52 	unsigned int	nr_pages_mid;
53 	unsigned int	folio_shift;
54 	unsigned int	nr_folios;
55 	unsigned long	first_folio_page_idx;
56 };
57 
58 bool io_rsrc_cache_init(struct io_ring_ctx *ctx);
59 void io_rsrc_cache_free(struct io_ring_ctx *ctx);
60 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type);
61 void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node);
62 void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data);
63 int io_rsrc_data_alloc(struct io_rsrc_data *data, unsigned nr);
64 
65 struct io_rsrc_node *io_find_buf_node(struct io_kiocb *req,
66 				      unsigned issue_flags);
67 int io_import_reg_buf(struct io_kiocb *req, struct iov_iter *iter,
68 			u64 buf_addr, size_t len, int ddir,
69 			unsigned issue_flags);
70 int io_import_reg_vec(int ddir, struct iov_iter *iter,
71 			struct io_kiocb *req, struct iou_vec *vec,
72 			unsigned nr_iovs, unsigned issue_flags);
73 int io_prep_reg_iovec(struct io_kiocb *req, struct iou_vec *iv,
74 			const struct iovec __user *uvec, size_t uvec_segs);
75 
76 int io_register_clone_buffers(struct io_ring_ctx *ctx, void __user *arg);
77 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
78 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
79 			    unsigned int nr_args, u64 __user *tags);
80 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
81 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
82 			  unsigned nr_args, u64 __user *tags);
83 
84 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
85 			     unsigned nr_args);
86 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
87 			    unsigned size, unsigned type);
88 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
89 			unsigned int size, unsigned int type);
90 int io_validate_user_buf_range(u64 uaddr, u64 ulen);
91 
92 bool io_check_coalesce_buffer(struct page **page_array, int nr_pages,
93 			      struct io_imu_folio_data *data);
94 
95 static inline struct io_rsrc_node *io_rsrc_node_lookup(struct io_rsrc_data *data,
96 						       unsigned int index)
97 {
98 	if (index < data->nr)
99 		return data->nodes[array_index_nospec(index, data->nr)];
100 	return NULL;
101 }
102 
103 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
104 {
105 	lockdep_assert_held(&ctx->uring_lock);
106 	if (!--node->refs)
107 		io_free_rsrc_node(ctx, node);
108 }
109 
110 static inline bool io_reset_rsrc_node(struct io_ring_ctx *ctx,
111 				      struct io_rsrc_data *data,
112 				      unsigned int index)
113 {
114 	struct io_rsrc_node *node;
115 
116 	if (index >= data->nr)
117 		return false;
118 	index = array_index_nospec(index, data->nr);
119 	node = data->nodes[index];
120 	if (!node)
121 		return false;
122 	io_put_rsrc_node(ctx, node);
123 	data->nodes[index] = NULL;
124 	return true;
125 }
126 
127 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
128 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
129 
130 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
131 int io_account_mem(struct user_struct *user, struct mm_struct *mm_account,
132 		   unsigned long nr_pages);
133 void io_unaccount_mem(struct user_struct *user, struct mm_struct *mm_account,
134 		      unsigned long nr_pages);
135 
136 static inline void __io_unaccount_mem(struct user_struct *user,
137 				      unsigned long nr_pages)
138 {
139 	atomic_long_sub(nr_pages, &user->locked_vm);
140 }
141 
142 void io_vec_free(struct iou_vec *iv);
143 int io_vec_realloc(struct iou_vec *iv, unsigned nr_entries);
144 
145 static inline void io_vec_reset_iovec(struct iou_vec *iv,
146 				      struct iovec *iovec, unsigned nr)
147 {
148 	io_vec_free(iv);
149 	iv->iovec = iovec;
150 	iv->nr = nr;
151 }
152 
153 static inline void io_alloc_cache_vec_kasan(struct iou_vec *iv)
154 {
155 	if (IS_ENABLED(CONFIG_KASAN))
156 		io_vec_free(iv);
157 }
158 
159 #endif
160