1 // SPDX-License-Identifier: GPL-2.0
2 #ifndef IOU_RSRC_H
3 #define IOU_RSRC_H
4 
5 #include <net/af_unix.h>
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 	struct list_head list;
18 	u64 tag;
19 	union {
20 		void *rsrc;
21 		struct file *file;
22 		struct io_mapped_ubuf *buf;
23 	};
24 };
25 
26 typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
27 
28 struct io_rsrc_data {
29 	struct io_ring_ctx		*ctx;
30 
31 	u64				**tags;
32 	unsigned int			nr;
33 	rsrc_put_fn			*do_put;
34 	atomic_t			refs;
35 	struct completion		done;
36 	bool				quiesce;
37 };
38 
39 struct io_rsrc_node {
40 	struct percpu_ref		refs;
41 	struct list_head		node;
42 	struct list_head		rsrc_list;
43 	struct io_rsrc_data		*rsrc_data;
44 	struct llist_node		llist;
45 	bool				done;
46 };
47 
48 struct io_mapped_ubuf {
49 	u64		ubuf;
50 	u64		ubuf_end;
51 	unsigned int	nr_bvecs;
52 	unsigned long	acct_pages;
53 	struct bio_vec	bvec[];
54 };
55 
56 void io_rsrc_put_work(struct work_struct *work);
57 void io_rsrc_refs_refill(struct io_ring_ctx *ctx);
58 void io_wait_rsrc_data(struct io_rsrc_data *data);
59 void io_rsrc_node_destroy(struct io_rsrc_node *ref_node);
60 void io_rsrc_refs_drop(struct io_ring_ctx *ctx);
61 int io_rsrc_node_switch_start(struct io_ring_ctx *ctx);
62 int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
63 			  struct io_rsrc_node *node, void *rsrc);
64 void io_rsrc_node_switch(struct io_ring_ctx *ctx,
65 			 struct io_rsrc_data *data_to_kill);
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 void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
72 int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
73 int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
74 			    unsigned int nr_args, u64 __user *tags);
75 void __io_sqe_files_unregister(struct io_ring_ctx *ctx);
76 int io_sqe_files_unregister(struct io_ring_ctx *ctx);
77 int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
78 			  unsigned nr_args, u64 __user *tags);
79 
80 int __io_scm_file_account(struct io_ring_ctx *ctx, struct file *file);
81 
82 #if defined(CONFIG_UNIX)
io_file_need_scm(struct file * filp)83 static inline bool io_file_need_scm(struct file *filp)
84 {
85 	return !!unix_get_socket(filp);
86 }
87 #else
io_file_need_scm(struct file * filp)88 static inline bool io_file_need_scm(struct file *filp)
89 {
90 	return false;
91 }
92 #endif
93 
io_scm_file_account(struct io_ring_ctx * ctx,struct file * file)94 static inline int io_scm_file_account(struct io_ring_ctx *ctx,
95 				      struct file *file)
96 {
97 	if (likely(!io_file_need_scm(file)))
98 		return 0;
99 	return __io_scm_file_account(ctx, file);
100 }
101 
102 int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
103 			     unsigned nr_args);
104 int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
105 			    unsigned size, unsigned type);
106 int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
107 			unsigned int size, unsigned int type);
108 
io_rsrc_put_node(struct io_rsrc_node * node,int nr)109 static inline void io_rsrc_put_node(struct io_rsrc_node *node, int nr)
110 {
111 	percpu_ref_put_many(&node->refs, nr);
112 }
113 
io_req_put_rsrc(struct io_kiocb * req)114 static inline void io_req_put_rsrc(struct io_kiocb *req)
115 {
116 	if (req->rsrc_node)
117 		io_rsrc_put_node(req->rsrc_node, 1);
118 }
119 
io_req_put_rsrc_locked(struct io_kiocb * req,struct io_ring_ctx * ctx)120 static inline void io_req_put_rsrc_locked(struct io_kiocb *req,
121 					  struct io_ring_ctx *ctx)
122 	__must_hold(&ctx->uring_lock)
123 {
124 	struct io_rsrc_node *node = req->rsrc_node;
125 
126 	if (node) {
127 		if (node == ctx->rsrc_node)
128 			ctx->rsrc_cached_refs++;
129 		else
130 			io_rsrc_put_node(node, 1);
131 	}
132 }
133 
io_charge_rsrc_node(struct io_ring_ctx * ctx)134 static inline void io_charge_rsrc_node(struct io_ring_ctx *ctx)
135 {
136 	ctx->rsrc_cached_refs--;
137 	if (unlikely(ctx->rsrc_cached_refs < 0))
138 		io_rsrc_refs_refill(ctx);
139 }
140 
io_req_set_rsrc_node(struct io_kiocb * req,struct io_ring_ctx * ctx,unsigned int issue_flags)141 static inline void io_req_set_rsrc_node(struct io_kiocb *req,
142 					struct io_ring_ctx *ctx,
143 					unsigned int issue_flags)
144 {
145 	if (!req->rsrc_node) {
146 		req->rsrc_node = ctx->rsrc_node;
147 
148 		if (!(issue_flags & IO_URING_F_UNLOCKED)) {
149 			lockdep_assert_held(&ctx->uring_lock);
150 
151 			io_charge_rsrc_node(ctx);
152 		} else {
153 			percpu_ref_get(&req->rsrc_node->refs);
154 		}
155 	}
156 }
157 
io_get_tag_slot(struct io_rsrc_data * data,unsigned int idx)158 static inline u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
159 {
160 	unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
161 	unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
162 
163 	return &data->tags[table_idx][off];
164 }
165 
166 int io_files_update(struct io_kiocb *req, unsigned int issue_flags);
167 int io_files_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
168 
169 int __io_account_mem(struct user_struct *user, unsigned long nr_pages);
170 
__io_unaccount_mem(struct user_struct * user,unsigned long nr_pages)171 static inline void __io_unaccount_mem(struct user_struct *user,
172 				      unsigned long nr_pages)
173 {
174 	atomic_long_sub(nr_pages, &user->locked_vm);
175 }
176 
177 #endif
178