xref: /linux/io_uring/rsrc.h (revision 3fd6c59042dbba50391e30862beac979491145fe)
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_node {
17 	unsigned char			type;
18 	int				refs;
19 
20 	u64 tag;
21 	union {
22 		unsigned long file_ptr;
23 		struct io_mapped_ubuf *buf;
24 	};
25 };
26 
27 struct io_mapped_ubuf {
28 	u64		ubuf;
29 	unsigned int	len;
30 	unsigned int	nr_bvecs;
31 	unsigned int    folio_shift;
32 	refcount_t	refs;
33 	unsigned long	acct_pages;
34 	struct bio_vec	bvec[] __counted_by(nr_bvecs);
35 };
36 
37 struct io_imu_folio_data {
38 	/* Head folio can be partially included in the fixed buf */
39 	unsigned int	nr_pages_head;
40 	/* For non-head/tail folios, has to be fully included */
41 	unsigned int	nr_pages_mid;
42 	unsigned int	folio_shift;
43 };
44 
45 struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx, int type);
46 void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node);
47 void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data);
48 int io_rsrc_data_alloc(struct io_rsrc_data *data, unsigned nr);
49 
50 int io_import_fixed(int ddir, struct iov_iter *iter,
51 			   struct io_mapped_ubuf *imu,
52 			   u64 buf_addr, size_t len);
53 
54 int io_register_clone_buffers(struct io_ring_ctx *ctx, void __user *arg);
55 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
56 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
57 			    unsigned int nr_args, u64 __user *tags);
58 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
59 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
60 			  unsigned nr_args, u64 __user *tags);
61 
62 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
63 			     unsigned nr_args);
64 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
65 			    unsigned size, unsigned type);
66 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
67 			unsigned int size, unsigned int type);
68 
io_rsrc_node_lookup(struct io_rsrc_data * data,int index)69 static inline struct io_rsrc_node *io_rsrc_node_lookup(struct io_rsrc_data *data,
70 						       int index)
71 {
72 	if (index < data->nr)
73 		return data->nodes[array_index_nospec(index, data->nr)];
74 	return NULL;
75 }
76 
io_put_rsrc_node(struct io_ring_ctx * ctx,struct io_rsrc_node * node)77 static inline void io_put_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node)
78 {
79 	if (node && !--node->refs)
80 		io_free_rsrc_node(ctx, node);
81 }
82 
io_reset_rsrc_node(struct io_ring_ctx * ctx,struct io_rsrc_data * data,int index)83 static inline bool io_reset_rsrc_node(struct io_ring_ctx *ctx,
84 				      struct io_rsrc_data *data, int index)
85 {
86 	struct io_rsrc_node *node = data->nodes[index];
87 
88 	if (!node)
89 		return false;
90 	io_put_rsrc_node(ctx, node);
91 	data->nodes[index] = NULL;
92 	return true;
93 }
94 
io_req_put_rsrc_nodes(struct io_kiocb * req)95 static inline void io_req_put_rsrc_nodes(struct io_kiocb *req)
96 {
97 	if (req->file_node) {
98 		io_put_rsrc_node(req->ctx, req->file_node);
99 		req->file_node = NULL;
100 	}
101 	if (req->flags & REQ_F_BUF_NODE) {
102 		io_put_rsrc_node(req->ctx, req->buf_node);
103 		req->buf_node = NULL;
104 	}
105 }
106 
io_req_assign_rsrc_node(struct io_rsrc_node ** dst_node,struct io_rsrc_node * node)107 static inline void io_req_assign_rsrc_node(struct io_rsrc_node **dst_node,
108 					   struct io_rsrc_node *node)
109 {
110 	node->refs++;
111 	*dst_node = node;
112 }
113 
io_req_assign_buf_node(struct io_kiocb * req,struct io_rsrc_node * node)114 static inline void io_req_assign_buf_node(struct io_kiocb *req,
115 					  struct io_rsrc_node *node)
116 {
117 	io_req_assign_rsrc_node(&req->buf_node, node);
118 	req->flags |= REQ_F_BUF_NODE;
119 }
120 
121 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
122 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
123 
124 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
125 
__io_unaccount_mem(struct user_struct * user,unsigned long nr_pages)126 static inline void __io_unaccount_mem(struct user_struct *user,
127 				      unsigned long nr_pages)
128 {
129 	atomic_long_sub(nr_pages, &user->locked_vm);
130 }
131 
132 #endif
133