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 11 struct seq_operations; 12 struct file; 13 struct path; 14 struct inode; 15 struct dentry; 16 struct user_namespace; 17 18 struct seq_file { 19 char *buf; 20 size_t size; 21 size_t from; 22 size_t count; 23 loff_t index; 24 loff_t read_pos; 25 u64 version; 26 struct mutex lock; 27 const struct seq_operations *op; 28 int poll_event; 29 #ifdef CONFIG_USER_NS 30 struct user_namespace *user_ns; 31 #endif 32 void *private; 33 }; 34 35 struct seq_operations { 36 void * (*start) (struct seq_file *m, loff_t *pos); 37 void (*stop) (struct seq_file *m, void *v); 38 void * (*next) (struct seq_file *m, void *v, loff_t *pos); 39 int (*show) (struct seq_file *m, void *v); 40 }; 41 42 #define SEQ_SKIP 1 43 44 /** 45 * seq_get_buf - get buffer to write arbitrary data to 46 * @m: the seq_file handle 47 * @bufp: the beginning of the buffer is stored here 48 * 49 * Return the number of bytes available in the buffer, or zero if 50 * there's no space. 51 */ 52 static inline size_t seq_get_buf(struct seq_file *m, char **bufp) 53 { 54 BUG_ON(m->count > m->size); 55 if (m->count < m->size) 56 *bufp = m->buf + m->count; 57 else 58 *bufp = NULL; 59 60 return m->size - m->count; 61 } 62 63 /** 64 * seq_commit - commit data to the buffer 65 * @m: the seq_file handle 66 * @num: the number of bytes to commit 67 * 68 * Commit @num bytes of data written to a buffer previously acquired 69 * by seq_buf_get. To signal an error condition, or that the data 70 * didn't fit in the available space, pass a negative @num value. 71 */ 72 static inline void seq_commit(struct seq_file *m, int num) 73 { 74 if (num < 0) { 75 m->count = m->size; 76 } else { 77 BUG_ON(m->count + num > m->size); 78 m->count += num; 79 } 80 } 81 82 char *mangle_path(char *s, const char *p, const char *esc); 83 int seq_open(struct file *, const struct seq_operations *); 84 ssize_t seq_read(struct file *, char __user *, size_t, loff_t *); 85 loff_t seq_lseek(struct file *, loff_t, int); 86 int seq_release(struct inode *, struct file *); 87 int seq_escape(struct seq_file *, const char *, const char *); 88 int seq_putc(struct seq_file *m, char c); 89 int seq_puts(struct seq_file *m, const char *s); 90 int seq_write(struct seq_file *seq, const void *data, size_t len); 91 92 __printf(2, 3) int seq_printf(struct seq_file *, const char *, ...); 93 __printf(2, 0) int seq_vprintf(struct seq_file *, const char *, va_list args); 94 95 int seq_path(struct seq_file *, const struct path *, const char *); 96 int seq_dentry(struct seq_file *, struct dentry *, const char *); 97 int seq_path_root(struct seq_file *m, const struct path *path, 98 const struct path *root, const char *esc); 99 int seq_bitmap(struct seq_file *m, const unsigned long *bits, 100 unsigned int nr_bits); 101 static inline int seq_cpumask(struct seq_file *m, const struct cpumask *mask) 102 { 103 return seq_bitmap(m, cpumask_bits(mask), nr_cpu_ids); 104 } 105 106 static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask) 107 { 108 return seq_bitmap(m, mask->bits, MAX_NUMNODES); 109 } 110 111 int seq_bitmap_list(struct seq_file *m, const unsigned long *bits, 112 unsigned int nr_bits); 113 114 static inline int seq_cpumask_list(struct seq_file *m, 115 const struct cpumask *mask) 116 { 117 return seq_bitmap_list(m, cpumask_bits(mask), nr_cpu_ids); 118 } 119 120 static inline int seq_nodemask_list(struct seq_file *m, nodemask_t *mask) 121 { 122 return seq_bitmap_list(m, mask->bits, MAX_NUMNODES); 123 } 124 125 int single_open(struct file *, int (*)(struct seq_file *, void *), void *); 126 int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t); 127 int single_release(struct inode *, struct file *); 128 void *__seq_open_private(struct file *, const struct seq_operations *, int); 129 int seq_open_private(struct file *, const struct seq_operations *, int); 130 int seq_release_private(struct inode *, struct file *); 131 int seq_put_decimal_ull(struct seq_file *m, char delimiter, 132 unsigned long long num); 133 int seq_put_decimal_ll(struct seq_file *m, char delimiter, 134 long long num); 135 136 static inline struct user_namespace *seq_user_ns(struct seq_file *seq) 137 { 138 #ifdef CONFIG_USER_NS 139 return seq->user_ns; 140 #else 141 extern struct user_namespace init_user_ns; 142 return &init_user_ns; 143 #endif 144 } 145 146 #define SEQ_START_TOKEN ((void *)1) 147 /* 148 * Helpers for iteration over list_head-s in seq_files 149 */ 150 151 extern struct list_head *seq_list_start(struct list_head *head, 152 loff_t pos); 153 extern struct list_head *seq_list_start_head(struct list_head *head, 154 loff_t pos); 155 extern struct list_head *seq_list_next(void *v, struct list_head *head, 156 loff_t *ppos); 157 158 /* 159 * Helpers for iteration over hlist_head-s in seq_files 160 */ 161 162 extern struct hlist_node *seq_hlist_start(struct hlist_head *head, 163 loff_t pos); 164 extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head, 165 loff_t pos); 166 extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head, 167 loff_t *ppos); 168 169 extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head, 170 loff_t pos); 171 extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head, 172 loff_t pos); 173 extern struct hlist_node *seq_hlist_next_rcu(void *v, 174 struct hlist_head *head, 175 loff_t *ppos); 176 177 /* Helpers for iterating over per-cpu hlist_head-s in seq_files */ 178 extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos); 179 180 extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos); 181 182 #endif 183