xref: /linux/io_uring/rsrc.h (revision f679ebf6aa9b42d0edb5b261e16dc7b1e3c3550e)
1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef IOU_RSRC_H
3 #define IOU_RSRC_H
4 
5 #include <linux/lockdep.h>
6 
7 enum {
8 	IORING_RSRC_FILE		= 0,
9 	IORING_RSRC_BUFFER		= 1,
10 };
11 
12 struct io_rsrc_node {
13 	unsigned char			type;
14 	int				refs;
15 
16 	u64 tag;
17 	union {
18 		unsigned long file_ptr;
19 		struct io_mapped_ubuf *buf;
20 	};
21 };
22 
23 struct io_mapped_ubuf {
24 	u64		ubuf;
25 	unsigned int	len;
26 	unsigned int	nr_bvecs;
27 	unsigned int    folio_shift;
28 	refcount_t	refs;
29 	unsigned long	acct_pages;
30 	struct bio_vec	bvec[] __counted_by(nr_bvecs);
31 };
32 
33 struct io_imu_folio_data {
34 	/* Head folio can be partially included in the fixed buf */
35 	unsigned int	nr_pages_head;
36 	/* For non-head/tail folios, has to be fully included */
37 	unsigned int	nr_pages_mid;
38 	unsigned int	folio_shift;
39 	unsigned int	nr_folios;
40 };
41 
42 struct io_rsrc_node *io_rsrc_node_alloc(int type);
43 void io_free_rsrc_node(struct io_ring_ctx *ctx, struct io_rsrc_node *node);
44 void io_rsrc_data_free(struct io_ring_ctx *ctx, struct io_rsrc_data *data);
45 int io_rsrc_data_alloc(struct io_rsrc_data *data, unsigned nr);
46 
47 int io_import_fixed(int ddir, struct iov_iter *iter,
48 			   struct io_mapped_ubuf *imu,
49 			   u64 buf_addr, size_t len);
50 
51 int io_register_clone_buffers(struct io_ring_ctx *ctx, void __user *arg);
52 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
53 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
54 			    unsigned int nr_args, u64 __user *tags);
55 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
56 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
57 			  unsigned nr_args, u64 __user *tags);
58 
59 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
60 			     unsigned nr_args);
61 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
62 			    unsigned size, unsigned type);
63 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
64 			unsigned int size, unsigned int type);
65 
66 bool io_check_coalesce_buffer(struct page **page_array, int nr_pages,
67 			      struct io_imu_folio_data *data);
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 	lockdep_assert_held(&ctx->uring_lock);
80 	if (node && !--node->refs)
81 		io_free_rsrc_node(ctx, node);
82 }
83 
io_reset_rsrc_node(struct io_ring_ctx * ctx,struct io_rsrc_data * data,int index)84 static inline bool io_reset_rsrc_node(struct io_ring_ctx *ctx,
85 				      struct io_rsrc_data *data, int index)
86 {
87 	struct io_rsrc_node *node = data->nodes[index];
88 
89 	if (!node)
90 		return false;
91 	io_put_rsrc_node(ctx, node);
92 	data->nodes[index] = NULL;
93 	return true;
94 }
95 
io_req_put_rsrc_nodes(struct io_kiocb * req)96 static inline void io_req_put_rsrc_nodes(struct io_kiocb *req)
97 {
98 	if (req->file_node) {
99 		io_put_rsrc_node(req->ctx, req->file_node);
100 		req->file_node = NULL;
101 	}
102 	if (req->flags & REQ_F_BUF_NODE) {
103 		io_put_rsrc_node(req->ctx, req->buf_node);
104 		req->buf_node = NULL;
105 	}
106 }
107 
io_req_assign_rsrc_node(struct io_rsrc_node ** dst_node,struct io_rsrc_node * node)108 static inline void io_req_assign_rsrc_node(struct io_rsrc_node **dst_node,
109 					   struct io_rsrc_node *node)
110 {
111 	node->refs++;
112 	*dst_node = node;
113 }
114 
io_req_assign_buf_node(struct io_kiocb * req,struct io_rsrc_node * node)115 static inline void io_req_assign_buf_node(struct io_kiocb *req,
116 					  struct io_rsrc_node *node)
117 {
118 	io_req_assign_rsrc_node(&req->buf_node, node);
119 	req->flags |= REQ_F_BUF_NODE;
120 }
121 
122 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
123 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
124 
125 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
126 
__io_unaccount_mem(struct user_struct * user,unsigned long nr_pages)127 static inline void __io_unaccount_mem(struct user_struct *user,
128 				      unsigned long nr_pages)
129 {
130 	atomic_long_sub(nr_pages, &user->locked_vm);
131 }
132 
133 #endif
134