~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/linux/fdtable.h

Version: ~ [ linux-5.3 ] ~ [ linux-5.2.15 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.73 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.144 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.193 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.193 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.73 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * descriptor table internals; you almost certainly want file.h instead.
  3  */
  4 
  5 #ifndef __LINUX_FDTABLE_H
  6 #define __LINUX_FDTABLE_H
  7 
  8 #include <linux/posix_types.h>
  9 #include <linux/compiler.h>
 10 #include <linux/spinlock.h>
 11 #include <linux/rcupdate.h>
 12 #include <linux/types.h>
 13 #include <linux/init.h>
 14 #include <linux/fs.h>
 15 
 16 #include <linux/atomic.h>
 17 
 18 /*
 19  * The default fd array needs to be at least BITS_PER_LONG,
 20  * as this is the granularity returned by copy_fdset().
 21  */
 22 #define NR_OPEN_DEFAULT BITS_PER_LONG
 23 
 24 struct fdtable {
 25         unsigned int max_fds;
 26         struct file __rcu **fd;      /* current fd array */
 27         unsigned long *close_on_exec;
 28         unsigned long *open_fds;
 29         unsigned long *full_fds_bits;
 30         struct rcu_head rcu;
 31 };
 32 
 33 static inline bool close_on_exec(unsigned int fd, const struct fdtable *fdt)
 34 {
 35         return test_bit(fd, fdt->close_on_exec);
 36 }
 37 
 38 static inline bool fd_is_open(unsigned int fd, const struct fdtable *fdt)
 39 {
 40         return test_bit(fd, fdt->open_fds);
 41 }
 42 
 43 /*
 44  * Open file table structure
 45  */
 46 struct files_struct {
 47   /*
 48    * read mostly part
 49    */
 50         atomic_t count;
 51         bool resize_in_progress;
 52         wait_queue_head_t resize_wait;
 53 
 54         struct fdtable __rcu *fdt;
 55         struct fdtable fdtab;
 56   /*
 57    * written part on a separate cache line in SMP
 58    */
 59         spinlock_t file_lock ____cacheline_aligned_in_smp;
 60         unsigned int next_fd;
 61         unsigned long close_on_exec_init[1];
 62         unsigned long open_fds_init[1];
 63         unsigned long full_fds_bits_init[1];
 64         struct file __rcu * fd_array[NR_OPEN_DEFAULT];
 65 };
 66 
 67 struct file_operations;
 68 struct vfsmount;
 69 struct dentry;
 70 
 71 #define rcu_dereference_check_fdtable(files, fdtfd) \
 72         rcu_dereference_check((fdtfd), lockdep_is_held(&(files)->file_lock))
 73 
 74 #define files_fdtable(files) \
 75         rcu_dereference_check_fdtable((files), (files)->fdt)
 76 
 77 /*
 78  * The caller must ensure that fd table isn't shared or hold rcu or file lock
 79  */
 80 static inline struct file *__fcheck_files(struct files_struct *files, unsigned int fd)
 81 {
 82         struct fdtable *fdt = rcu_dereference_raw(files->fdt);
 83 
 84         if (fd < fdt->max_fds)
 85                 return rcu_dereference_raw(fdt->fd[fd]);
 86         return NULL;
 87 }
 88 
 89 static inline struct file *fcheck_files(struct files_struct *files, unsigned int fd)
 90 {
 91         RCU_LOCKDEP_WARN(!rcu_read_lock_held() &&
 92                            !lockdep_is_held(&files->file_lock),
 93                            "suspicious rcu_dereference_check() usage");
 94         return __fcheck_files(files, fd);
 95 }
 96 
 97 /*
 98  * Check whether the specified fd has an open file.
 99  */
100 #define fcheck(fd)      fcheck_files(current->files, fd)
101 
102 struct task_struct;
103 
104 struct files_struct *get_files_struct(struct task_struct *);
105 void put_files_struct(struct files_struct *fs);
106 void reset_files_struct(struct files_struct *);
107 int unshare_files(struct files_struct **);
108 struct files_struct *dup_fd(struct files_struct *, int *) __latent_entropy;
109 void do_close_on_exec(struct files_struct *);
110 int iterate_fd(struct files_struct *, unsigned,
111                 int (*)(const void *, struct file *, unsigned),
112                 const void *);
113 
114 extern int __alloc_fd(struct files_struct *files,
115                       unsigned start, unsigned end, unsigned flags);
116 extern void __fd_install(struct files_struct *files,
117                       unsigned int fd, struct file *file);
118 extern int __close_fd(struct files_struct *files,
119                       unsigned int fd);
120 
121 extern struct kmem_cache *files_cachep;
122 
123 #endif /* __LINUX_FDTABLE_H */
124 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp