245 lines
		
	
	
		
			7.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			245 lines
		
	
	
		
			7.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef _LINUX_SEQ_FILE_H
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| #define _LINUX_SEQ_FILE_H
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| 
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| #include <linux/types.h>
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| #include <linux/string.h>
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| #include <linux/bug.h>
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| #include <linux/mutex.h>
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| #include <linux/cpumask.h>
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| #include <linux/nodemask.h>
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| #include <linux/fs.h>
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| #include <linux/cred.h>
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| 
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| struct seq_operations;
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| 
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| struct seq_file {
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| 	char *buf;
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| 	size_t size;
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| 	size_t from;
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| 	size_t count;
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| 	size_t pad_until;
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| 	loff_t index;
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| 	loff_t read_pos;
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| 	u64 version;
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| 	struct mutex lock;
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| 	const struct seq_operations *op;
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| 	int poll_event;
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| 	const struct file *file;
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| 	void *private;
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| };
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| 
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| struct seq_operations {
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| 	void * (*start) (struct seq_file *m, loff_t *pos);
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| 	void (*stop) (struct seq_file *m, void *v);
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| 	void * (*next) (struct seq_file *m, void *v, loff_t *pos);
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| 	int (*show) (struct seq_file *m, void *v);
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| };
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| 
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| #define SEQ_SKIP 1
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| 
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| /**
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|  * seq_has_overflowed - check if the buffer has overflowed
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|  * @m: the seq_file handle
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|  *
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|  * seq_files have a buffer which may overflow. When this happens a larger
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|  * buffer is reallocated and all the data will be printed again.
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|  * The overflow state is true when m->count == m->size.
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|  *
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|  * Returns true if the buffer received more than it can hold.
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|  */
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| static inline bool seq_has_overflowed(struct seq_file *m)
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| {
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| 	return m->count == m->size;
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| }
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| 
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| /**
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|  * seq_get_buf - get buffer to write arbitrary data to
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|  * @m: the seq_file handle
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|  * @bufp: the beginning of the buffer is stored here
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|  *
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|  * Return the number of bytes available in the buffer, or zero if
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|  * there's no space.
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|  */
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| static inline size_t seq_get_buf(struct seq_file *m, char **bufp)
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| {
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| 	BUG_ON(m->count > m->size);
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| 	if (m->count < m->size)
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| 		*bufp = m->buf + m->count;
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| 	else
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| 		*bufp = NULL;
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| 
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| 	return m->size - m->count;
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| }
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| 
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| /**
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|  * seq_commit - commit data to the buffer
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|  * @m: the seq_file handle
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|  * @num: the number of bytes to commit
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|  *
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|  * Commit @num bytes of data written to a buffer previously acquired
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|  * by seq_buf_get.  To signal an error condition, or that the data
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|  * didn't fit in the available space, pass a negative @num value.
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|  */
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| static inline void seq_commit(struct seq_file *m, int num)
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| {
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| 	if (num < 0) {
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| 		m->count = m->size;
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| 	} else {
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| 		BUG_ON(m->count + num > m->size);
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| 		m->count += num;
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| 	}
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| }
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| 
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| /**
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|  * seq_setwidth - set padding width
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|  * @m: the seq_file handle
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|  * @size: the max number of bytes to pad.
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|  *
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|  * Call seq_setwidth() for setting max width, then call seq_printf() etc. and
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|  * finally call seq_pad() to pad the remaining bytes.
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|  */
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| static inline void seq_setwidth(struct seq_file *m, size_t size)
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| {
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| 	m->pad_until = m->count + size;
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| }
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| void seq_pad(struct seq_file *m, char c);
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| 
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| char *mangle_path(char *s, const char *p, const char *esc);
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| int seq_open(struct file *, const struct seq_operations *);
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| ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
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| loff_t seq_lseek(struct file *, loff_t, int);
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| int seq_release(struct inode *, struct file *);
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| int seq_write(struct seq_file *seq, const void *data, size_t len);
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| 
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| __printf(2, 0)
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| void seq_vprintf(struct seq_file *m, const char *fmt, va_list args);
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| __printf(2, 3)
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| void seq_printf(struct seq_file *m, const char *fmt, ...);
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| void seq_putc(struct seq_file *m, char c);
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| void seq_puts(struct seq_file *m, const char *s);
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| void seq_put_decimal_ull_width(struct seq_file *m, const char *delimiter,
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| 			       unsigned long long num, unsigned int width);
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| void seq_put_decimal_ull(struct seq_file *m, const char *delimiter,
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| 			 unsigned long long num);
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| void seq_put_decimal_ll(struct seq_file *m, const char *delimiter, long long num);
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| void seq_put_hex_ll(struct seq_file *m, const char *delimiter,
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| 		    unsigned long long v, unsigned int width);
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| 
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| void seq_escape(struct seq_file *m, const char *s, const char *esc);
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| 
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| void seq_hex_dump(struct seq_file *m, const char *prefix_str, int prefix_type,
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| 		  int rowsize, int groupsize, const void *buf, size_t len,
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| 		  bool ascii);
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| 
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| int seq_path(struct seq_file *, const struct path *, const char *);
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| int seq_file_path(struct seq_file *, struct file *, const char *);
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| int seq_dentry(struct seq_file *, struct dentry *, const char *);
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| int seq_path_root(struct seq_file *m, const struct path *path,
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| 		  const struct path *root, const char *esc);
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| 
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| int single_open(struct file *, int (*)(struct seq_file *, void *), void *);
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| int single_open_size(struct file *, int (*)(struct seq_file *, void *), void *, size_t);
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| int single_release(struct inode *, struct file *);
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| void *__seq_open_private(struct file *, const struct seq_operations *, int);
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| int seq_open_private(struct file *, const struct seq_operations *, int);
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| int seq_release_private(struct inode *, struct file *);
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| 
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| #define DEFINE_SHOW_ATTRIBUTE(__name)					\
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| static int __name ## _open(struct inode *inode, struct file *file)	\
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| {									\
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| 	return single_open(file, __name ## _show, inode->i_private);	\
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| }									\
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| 									\
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| static const struct file_operations __name ## _fops = {			\
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| 	.owner		= THIS_MODULE,					\
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| 	.open		= __name ## _open,				\
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| 	.read		= seq_read,					\
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| 	.llseek		= seq_lseek,					\
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| 	.release	= single_release,				\
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| }
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| 
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| static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
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| {
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| #ifdef CONFIG_USER_NS
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| 	return seq->file->f_cred->user_ns;
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| #else
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| 	extern struct user_namespace init_user_ns;
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| 	return &init_user_ns;
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| #endif
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| }
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| 
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| /**
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|  * seq_show_options - display mount options with appropriate escapes.
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|  * @m: the seq_file handle
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|  * @name: the mount option name
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|  * @value: the mount option name's value, can be NULL
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|  */
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| static inline void seq_show_option(struct seq_file *m, const char *name,
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| 				   const char *value)
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| {
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| 	seq_putc(m, ',');
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| 	seq_escape(m, name, ",= \t\n\\");
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| 	if (value) {
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| 		seq_putc(m, '=');
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| 		seq_escape(m, value, ", \t\n\\");
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| 	}
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| }
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| 
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| /**
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|  * seq_show_option_n - display mount options with appropriate escapes
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|  *		       where @value must be a specific length.
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|  * @m: the seq_file handle
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|  * @name: the mount option name
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|  * @value: the mount option name's value, cannot be NULL
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|  * @length: the length of @value to display
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|  *
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|  * This is a macro since this uses "length" to define the size of the
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|  * stack buffer.
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|  */
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| #define seq_show_option_n(m, name, value, length) {	\
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| 	char val_buf[length + 1];			\
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| 	strncpy(val_buf, value, length);		\
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| 	val_buf[length] = '\0';				\
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| 	seq_show_option(m, name, val_buf);		\
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| }
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| 
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| #define SEQ_START_TOKEN ((void *)1)
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| /*
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|  * Helpers for iteration over list_head-s in seq_files
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|  */
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| 
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| extern struct list_head *seq_list_start(struct list_head *head,
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| 		loff_t pos);
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| extern struct list_head *seq_list_start_head(struct list_head *head,
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| 		loff_t pos);
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| extern struct list_head *seq_list_next(void *v, struct list_head *head,
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| 		loff_t *ppos);
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| 
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| /*
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|  * Helpers for iteration over hlist_head-s in seq_files
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|  */
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| 
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| extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
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| 					  loff_t pos);
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| extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
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| 					       loff_t pos);
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| extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
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| 					 loff_t *ppos);
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| 
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| extern struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
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| 					      loff_t pos);
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| extern struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
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| 						   loff_t pos);
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| extern struct hlist_node *seq_hlist_next_rcu(void *v,
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| 						   struct hlist_head *head,
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| 						   loff_t *ppos);
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| 
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| /* Helpers for iterating over per-cpu hlist_head-s in seq_files */
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| extern struct hlist_node *seq_hlist_start_percpu(struct hlist_head __percpu *head, int *cpu, loff_t pos);
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| 
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| extern struct hlist_node *seq_hlist_next_percpu(void *v, struct hlist_head __percpu *head, int *cpu, loff_t *pos);
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| 
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| void seq_file_init(void);
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| #endif
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