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1#ifndef _LINUX_SEQ_FILE_H
2#define _LINUX_SEQ_FILE_H
3
4#include <linux/types.h>
5#include <linux/string.h>
6#include <linux/bug.h>
7#include <linux/mutex.h>
8#include <linux/cpumask.h>
9#include <linux/nodemask.h>
10
11struct seq_operations;
12struct file;
13struct path;
14struct inode;
15struct dentry;
16struct user_namespace;
17
18struct seq_file {
19 char *buf;
20 size_t size;
21 size_t from;
22 size_t count;
23 size_t pad_until;
24 loff_t index;
25 loff_t read_pos;
26 u64 version;
27 struct mutex lock;
28 const struct seq_operations *op;
29 int poll_event;
30#ifdef CONFIG_USER_NS
31 struct user_namespace *user_ns;
32#endif
33 void *private;
34};
35
36struct seq_operations {
37 void * (*start) (struct seq_file *m, loff_t *pos);
38 void (*stop) (struct seq_file *m, void *v);
39 void * (*next) (struct seq_file *m, void *v, loff_t *pos);
40 int (*show) (struct seq_file *m, void *v);
41};
42
43#define SEQ_SKIP 1
44
45/**
46 * seq_get_buf - get buffer to write arbitrary data to
47 * @m: the seq_file handle
48 * @bufp: the beginning of the buffer is stored here
49 *
50 * Return the number of bytes available in the buffer, or zero if
51 * there's no space.
52 */
53static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
54{
55 BUG_ON(m->count > m->size);
56 if (m->count < m->size)
57 *bufp = m->buf + m->count;
58 else
59 *bufp = NULL;
60
61 return m->size - m->count;
62}
63
64/**
65 * seq_commit - commit data to the buffer
66 * @m: the seq_file handle
67 * @num: the number of bytes to commit
68 *
69 * Commit @num bytes of data written to a buffer previously acquired
70 * by seq_buf_get. To signal an error condition, or that the data
71 * didn't fit in the available space, pass a negative @num value.
72 */
73static inline void seq_commit(struct seq_file *m, int num)
74{
75 if (num < 0) {
76 m->count = m->size;
77 } else {
78 BUG_ON(m->count + num > m->size);
79 m->count += num;
80 }
81}
82
83/**
84 * seq_setwidth - set padding width
85 * @m: the seq_file handle
86 * @size: the max number of bytes to pad.
87 *
88 * Call seq_setwidth() for setting max width, then call seq_printf() etc. and
89 * finally call seq_pad() to pad the remaining bytes.
90 */
91static inline void seq_setwidth(struct seq_file *m, size_t size)
92{
93 m->pad_until = m->count + size;
94}
95void seq_pad(struct seq_file *m, char c);
96
97char *mangle_path(char *s, const char *p, const char *esc);
98int seq_open(struct file *, const struct seq_operations *);
99ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
100loff_t seq_lseek(struct file *, loff_t, int);
101int seq_release(struct inode *, struct file *);
102int seq_escape(struct seq_file *, const char *, const char *);
103int seq_putc(struct seq_file *m, char c);
104int seq_puts(struct seq_file *m, const char *s);
105int seq_write(struct seq_file *seq, const void *data, size_t len);
106
107__printf(2, 3) int seq_printf(struct seq_file *, const char *, ...);
108__printf(2, 0) int seq_vprintf(struct seq_file *, const char *, va_list args);
109
110int seq_path(struct seq_file *, const struct path *, const char *);
111int seq_dentry(struct seq_file *, struct dentry *, const char *);
112int seq_path_root(struct seq_file *m, const struct path *path,
113 const struct path *root, const char *esc);
114int seq_bitmap(struct seq_file *m, const unsigned long *bits,
115 unsigned int nr_bits);
116static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask)
117{
118 return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids);
119}
120
121static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask)
122{
123 return seq_bitmap(m, mask->bits, MAX_NUMNODES);
124}
125
126int seq_bitmap_list(struct seq_file *m, const unsigned long *bits,
127 unsigned int nr_bits);
128
129static inline int seq_cpumask_list(struct seq_file *m,
130 const struct cpumask *mask)
131{
132 return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids);
133}
134
135static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask)
136{
137 return seq_bitmap_list(m, mask->bits, MAX_NUMNODES);
138}
139
140int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
141int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t);
142int single_release(struct inode *, struct file *);
143void *__seq_open_private(struct file *, const struct seq_operations *, int);
144int seq_open_private(struct file *, const struct seq_operations *, int);
145int seq_release_private(struct inode *, struct file *);
146int seq_put_decimal_ull(struct seq_file *m, char delimiter,
147 unsigned long long num);
148int seq_put_decimal_ll(struct seq_file *m, char delimiter,
149 long long num);
150
151static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
152{
153#ifdef CONFIG_USER_NS
154 return seq->user_ns;
155#else
156 extern struct user_namespace init_user_ns;
157 return &init_user_ns;
158#endif
159}
160
161#define SEQ_START_TOKEN ((void *)1)
162/*
163 * Helpers for iteration over list_head-s in seq_files
164 */
165
166extern struct list_head *seq_list_start(struct list_head *head,
167 loff_t pos);
168extern struct list_head *seq_list_start_head(struct list_head *head,
169 loff_t pos);
170extern struct list_head *seq_list_next(void *v, struct list_head *head,
171 loff_t *ppos);
172
173/*
174 * Helpers for iteration over hlist_head-s in seq_files
175 */
176
177extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
178 loff_t pos);
179extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
180 loff_t pos);
181extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
182 loff_t *ppos);
183
184extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
185 loff_t pos);
186extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
187 loff_t pos);
188extern struct hlist_node *seq_hlist_next_rcu(void *v,
189 struct hlist_head *head,
190 loff_t *ppos);
191
192/* Helpers for iterating over per-cpu hlist_head-s in seq_files */
193extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos);
194
195extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos);
196
197#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_SEQ_FILE_H
3#define _LINUX_SEQ_FILE_H
4
5#include <linux/types.h>
6#include <linux/string.h>
7#include <linux/string_helpers.h>
8#include <linux/bug.h>
9#include <linux/mutex.h>
10#include <linux/cpumask.h>
11#include <linux/nodemask.h>
12#include <linux/fs.h>
13#include <linux/cred.h>
14
15struct seq_operations;
16
17struct seq_file {
18 char *buf;
19 size_t size;
20 size_t from;
21 size_t count;
22 size_t pad_until;
23 loff_t index;
24 loff_t read_pos;
25 struct mutex lock;
26 const struct seq_operations *op;
27 int poll_event;
28 const struct file *file;
29 void *private;
30};
31
32struct seq_operations {
33 void * (*start) (struct seq_file *m, loff_t *pos);
34 void (*stop) (struct seq_file *m, void *v);
35 void * (*next) (struct seq_file *m, void *v, loff_t *pos);
36 int (*show) (struct seq_file *m, void *v);
37};
38
39#define SEQ_SKIP 1
40
41/**
42 * seq_has_overflowed - check if the buffer has overflowed
43 * @m: the seq_file handle
44 *
45 * seq_files have a buffer which may overflow. When this happens a larger
46 * buffer is reallocated and all the data will be printed again.
47 * The overflow state is true when m->count == m->size.
48 *
49 * Returns true if the buffer received more than it can hold.
50 */
51static inline bool seq_has_overflowed(struct seq_file *m)
52{
53 return m->count == m->size;
54}
55
56/**
57 * seq_get_buf - get buffer to write arbitrary data to
58 * @m: the seq_file handle
59 * @bufp: the beginning of the buffer is stored here
60 *
61 * Return the number of bytes available in the buffer, or zero if
62 * there's no space.
63 */
64static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
65{
66 BUG_ON(m->count > m->size);
67 if (m->count < m->size)
68 *bufp = m->buf + m->count;
69 else
70 *bufp = NULL;
71
72 return m->size - m->count;
73}
74
75/**
76 * seq_commit - commit data to the buffer
77 * @m: the seq_file handle
78 * @num: the number of bytes to commit
79 *
80 * Commit @num bytes of data written to a buffer previously acquired
81 * by seq_buf_get. To signal an error condition, or that the data
82 * didn't fit in the available space, pass a negative @num value.
83 */
84static inline void seq_commit(struct seq_file *m, int num)
85{
86 if (num < 0) {
87 m->count = m->size;
88 } else {
89 BUG_ON(m->count + num > m->size);
90 m->count += num;
91 }
92}
93
94/**
95 * seq_setwidth - set padding width
96 * @m: the seq_file handle
97 * @size: the max number of bytes to pad.
98 *
99 * Call seq_setwidth() for setting max width, then call seq_printf() etc. and
100 * finally call seq_pad() to pad the remaining bytes.
101 */
102static inline void seq_setwidth(struct seq_file *m, size_t size)
103{
104 m->pad_until = m->count + size;
105}
106void seq_pad(struct seq_file *m, char c);
107
108char *mangle_path(char *s, const char *p, const char *esc);
109int seq_open(struct file *, const struct seq_operations *);
110ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
111ssize_t seq_read_iter(struct kiocb *iocb, struct iov_iter *iter);
112loff_t seq_lseek(struct file *, loff_t, int);
113int seq_release(struct inode *, struct file *);
114int seq_write(struct seq_file *seq, const void *data, size_t len);
115
116__printf(2, 0)
117void seq_vprintf(struct seq_file *m, const char *fmt, va_list args);
118__printf(2, 3)
119void seq_printf(struct seq_file *m, const char *fmt, ...);
120void seq_putc(struct seq_file *m, char c);
121void seq_puts(struct seq_file *m, const char *s);
122void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter,
123 unsigned long long num, unsigned int width);
124void seq_put_decimal_ull(struct seq_file *m, const char *delimiter,
125 unsigned long long num);
126void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num);
127void seq_put_hex_ll(struct seq_file *m, const char *delimiter,
128 unsigned long long v, unsigned int width);
129
130void seq_escape_mem(struct seq_file *m, const char *src, size_t len,
131 unsigned int flags, const char *esc);
132
133static inline void seq_escape_str(struct seq_file *m, const char *src,
134 unsigned int flags, const char *esc)
135{
136 seq_escape_mem(m, src, strlen(src), flags, esc);
137}
138
139/**
140 * seq_escape - print string into buffer, escaping some characters
141 * @m: target buffer
142 * @s: NULL-terminated string
143 * @esc: set of characters that need escaping
144 *
145 * Puts string into buffer, replacing each occurrence of character from
146 * @esc with usual octal escape.
147 *
148 * Use seq_has_overflowed() to check for errors.
149 */
150static inline void seq_escape(struct seq_file *m, const char *s, const char *esc)
151{
152 seq_escape_str(m, s, ESCAPE_OCTAL, esc);
153}
154
155void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type,
156 int rowsize, int groupsize, const void *buf, size_t len,
157 bool ascii);
158
159int seq_path(struct seq_file *, const struct path *, const char *);
160int seq_file_path(struct seq_file *, struct file *, const char *);
161int seq_dentry(struct seq_file *, struct dentry *, const char *);
162int seq_path_root(struct seq_file *m, const struct path *path,
163 const struct path *root, const char *esc);
164
165void *single_start(struct seq_file *, loff_t *);
166int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
167int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t);
168int single_release(struct inode *, struct file *);
169void *__seq_open_private(struct file *, const struct seq_operations *, int);
170int seq_open_private(struct file *, const struct seq_operations *, int);
171int seq_release_private(struct inode *, struct file *);
172
173#ifdef CONFIG_BINARY_PRINTF
174void seq_bprintf(struct seq_file *m, const char *f, const u32 *binary);
175#endif
176
177#define DEFINE_SEQ_ATTRIBUTE(__name) \
178static int __name ## _open(struct inode *inode, struct file *file) \
179{ \
180 int ret = seq_open(file, &__name ## _sops); \
181 if (!ret && inode->i_private) { \
182 struct seq_file *seq_f = file->private_data; \
183 seq_f->private = inode->i_private; \
184 } \
185 return ret; \
186} \
187 \
188static const struct file_operations __name ## _fops = { \
189 .owner = THIS_MODULE, \
190 .open = __name ## _open, \
191 .read = seq_read, \
192 .llseek = seq_lseek, \
193 .release = seq_release, \
194}
195
196#define DEFINE_SHOW_ATTRIBUTE(__name) \
197static int __name ## _open(struct inode *inode, struct file *file) \
198{ \
199 return single_open(file, __name ## _show, inode->i_private); \
200} \
201 \
202static const struct file_operations __name ## _fops = { \
203 .owner = THIS_MODULE, \
204 .open = __name ## _open, \
205 .read = seq_read, \
206 .llseek = seq_lseek, \
207 .release = single_release, \
208}
209
210#define DEFINE_SHOW_STORE_ATTRIBUTE(__name) \
211static int __name ## _open(struct inode *inode, struct file *file) \
212{ \
213 return single_open(file, __name ## _show, inode->i_private); \
214} \
215 \
216static const struct file_operations __name ## _fops = { \
217 .owner = THIS_MODULE, \
218 .open = __name ## _open, \
219 .read = seq_read, \
220 .write = __name ## _write, \
221 .llseek = seq_lseek, \
222 .release = single_release, \
223}
224
225#define DEFINE_PROC_SHOW_ATTRIBUTE(__name) \
226static int __name ## _open(struct inode *inode, struct file *file) \
227{ \
228 return single_open(file, __name ## _show, pde_data(inode)); \
229} \
230 \
231static const struct proc_ops __name ## _proc_ops = { \
232 .proc_open = __name ## _open, \
233 .proc_read = seq_read, \
234 .proc_lseek = seq_lseek, \
235 .proc_release = single_release, \
236}
237
238static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
239{
240#ifdef CONFIG_USER_NS
241 return seq->file->f_cred->user_ns;
242#else
243 extern struct user_namespace init_user_ns;
244 return &init_user_ns;
245#endif
246}
247
248/**
249 * seq_show_options - display mount options with appropriate escapes.
250 * @m: the seq_file handle
251 * @name: the mount option name
252 * @value: the mount option name's value, can be NULL
253 */
254static inline void seq_show_option(struct seq_file *m, const char *name,
255 const char *value)
256{
257 seq_putc(m, ',');
258 seq_escape(m, name, ",= \t\n\\");
259 if (value) {
260 seq_putc(m, '=');
261 seq_escape(m, value, ", \t\n\\");
262 }
263}
264
265/**
266 * seq_show_option_n - display mount options with appropriate escapes
267 * where @value must be a specific length (i.e.
268 * not NUL-terminated).
269 * @m: the seq_file handle
270 * @name: the mount option name
271 * @value: the mount option name's value, cannot be NULL
272 * @length: the exact length of @value to display, must be constant expression
273 *
274 * This is a macro since this uses "length" to define the size of the
275 * stack buffer.
276 */
277#define seq_show_option_n(m, name, value, length) { \
278 char val_buf[length + 1]; \
279 memcpy(val_buf, value, length); \
280 val_buf[length] = '\0'; \
281 seq_show_option(m, name, val_buf); \
282}
283
284#define SEQ_START_TOKEN ((void *)1)
285/*
286 * Helpers for iteration over list_head-s in seq_files
287 */
288
289extern struct list_head *seq_list_start(struct list_head *head,
290 loff_t pos);
291extern struct list_head *seq_list_start_head(struct list_head *head,
292 loff_t pos);
293extern struct list_head *seq_list_next(void *v, struct list_head *head,
294 loff_t *ppos);
295
296extern struct list_head *seq_list_start_rcu(struct list_head *head, loff_t pos);
297extern struct list_head *seq_list_start_head_rcu(struct list_head *head, loff_t pos);
298extern struct list_head *seq_list_next_rcu(void *v, struct list_head *head, loff_t *ppos);
299
300/*
301 * Helpers for iteration over hlist_head-s in seq_files
302 */
303
304extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
305 loff_t pos);
306extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
307 loff_t pos);
308extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
309 loff_t *ppos);
310
311extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
312 loff_t pos);
313extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
314 loff_t pos);
315extern struct hlist_node *seq_hlist_next_rcu(void *v,
316 struct hlist_head *head,
317 loff_t *ppos);
318
319/* Helpers for iterating over per-cpu hlist_head-s in seq_files */
320extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos);
321
322extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos);
323
324void seq_file_init(void);
325#endif