Release 4.12 include/linux/fdtable.h

/*
 * descriptor table internals; you almost certainly want file.h instead.
 */

#ifndef __LINUX_FDTABLE_H

#define __LINUX_FDTABLE_H

#include <linux/posix_types.h>
#include <linux/compiler.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/fs.h>

#include <linux/atomic.h>

/*
 * The default fd array needs to be at least BITS_PER_LONG,
 * as this is the granularity returned by copy_fdset().
 */

#define NR_OPEN_DEFAULT BITS_PER_LONG


struct fdtable {
	
unsigned int max_fds;
	
struct file __rcu **fd;      /* current fd array */
	
unsigned long *close_on_exec;
	
unsigned long *open_fds;
	
unsigned long *full_fds_bits;
	
struct rcu_head rcu;
};



static inline bool close_on_exec(unsigned int fd, const struct fdtable *fdt)
{
	return test_bit(fd, fdt->close_on_exec);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Howells
26
96.30%
2
66.67%
Alexey Dobriyan
1
3.70%
1
33.33%
Total
27
100.00%
3
100.00%



static inline bool fd_is_open(unsigned int fd, const struct fdtable *fdt)
{
	return test_bit(fd, fdt->open_fds);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
David Howells
26
96.30%
2
66.67%
Alexey Dobriyan
1
3.70%
1
33.33%
Total
27
100.00%
3
100.00%

/*
 * Open file table structure
 */

struct files_struct {
  /*
   * read mostly part
   */
	
atomic_t count;
	
bool resize_in_progress;
	
wait_queue_head_t resize_wait;

	
struct fdtable __rcu *fdt;
	
struct fdtable fdtab;
  /*
   * written part on a separate cache line in SMP
   */
	
spinlock_t file_lock ____cacheline_aligned_in_smp;
	
unsigned int next_fd;
	
unsigned long close_on_exec_init[1];
	
unsigned long open_fds_init[1];
	
unsigned long full_fds_bits_init[1];
	
struct file __rcu * fd_array[NR_OPEN_DEFAULT];
};

struct file_operations;
struct vfsmount;
struct dentry;


#define rcu_dereference_check_fdtable(files, fdtfd) \
	rcu_dereference_check((fdtfd), lockdep_is_held(&(files)->file_lock))


#define files_fdtable(files) \
	rcu_dereference_check_fdtable((files), (files)->fdt)

/*
 * The caller must ensure that fd table isn't shared or hold rcu or file lock
 */


static inline struct file *__fcheck_files(struct files_struct *files, unsigned int fd)
{
	struct fdtable *fdt = rcu_dereference_raw(files->fdt);

	if (fd < fdt->max_fds)
		return rcu_dereference_raw(fdt->fd[fd]);
	return NULL;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Al Viro
42
80.77%
1
50.00%
Oleg Nesterov
10
19.23%
1
50.00%
Total
52
100.00%
2
100.00%



static inline struct file *fcheck_files(struct files_struct *files, unsigned int fd)
{
	RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&
			   !lockdep_is_held(&files->file_lock),
			   "suspicious rcu_dereference_check() usage");
	return __fcheck_files(files, fd);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Oleg Nesterov
37
84.09%
1
33.33%
Paul E. McKenney
4
9.09%
1
33.33%
Al Viro
3
6.82%
1
33.33%
Total
44
100.00%
3
100.00%

/*
 * Check whether the specified fd has an open file.
 */

#define fcheck(fd)	fcheck_files(current->files, fd)

struct task_struct;

struct files_struct *get_files_struct(struct task_struct *);
void put_files_struct(struct files_struct *fs);
void reset_files_struct(struct files_struct *);
int unshare_files(struct files_struct **);
struct files_struct *dup_fd(struct files_struct *, int *) __latent_entropy;
void do_close_on_exec(struct files_struct *);
int iterate_fd(struct files_struct *, unsigned,
		int (*)(const void *, struct file *, unsigned),
		const void *);

extern int __alloc_fd(struct files_struct *files,
		      unsigned start, unsigned end, unsigned flags);
extern void __fd_install(struct files_struct *files,
		      unsigned int fd, struct file *file);
extern int __close_fd(struct files_struct *files,
		      unsigned int fd);

extern struct kmem_cache *files_cachep;

#endif /* __LINUX_FDTABLE_H */
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Al Viro
298
62.74%
7
36.84%
David Howells
66
13.89%
2
10.53%
Oleg Nesterov
66
13.89%
1
5.26%
Linus Torvalds
12
2.53%
1
5.26%
Emese Revfy
8
1.68%
1
5.26%
Paul E. McKenney
7
1.47%
2
10.53%
Eric Dumazet
6
1.26%
1
5.26%
Ingo Molnar
5
1.05%
1
5.26%
Alexey Dobriyan
3
0.63%
1
5.26%
Arnd Bergmann
3
0.63%
1
5.26%
Arun Sharma
1
0.21%
1
5.26%
Total
475
100.00%
19
100.00%
Directory: include/linux

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.