diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2008-05-02 14:23:14 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-05-02 14:23:14 -0400 |
| commit | b66e1f11ebc429569a3784aaf64123633d9e3ed1 (patch) | |
| tree | d49f96acc682aaf29416921428110da5fd78fea4 /include/linux/fdtable.h | |
| parent | 1be1d6b7f3f6e3a87f872dd5e7a867d03d8a6851 (diff) | |
| parent | 5c598b3428c372a1209597cee99a70da20625876 (diff) | |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] fix sysctl_nr_open bugs
[PATCH] sanitize anon_inode_getfd()
[PATCH] split linux/file.h
[PATCH] make osf_select() use core_sys_select()
[PATCH] remove horrors with irix tty ioctls handling
[PATCH] fix file and descriptor handling in perfmon
Diffstat (limited to 'include/linux/fdtable.h')
| -rw-r--r-- | include/linux/fdtable.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/include/linux/fdtable.h b/include/linux/fdtable.h new file mode 100644 index 000000000000..a118f3c0b240 --- /dev/null +++ b/include/linux/fdtable.h | |||
| @@ -0,0 +1,99 @@ | |||
| 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 <asm/atomic.h> | ||
| 9 | #include <linux/posix_types.h> | ||
| 10 | #include <linux/compiler.h> | ||
| 11 | #include <linux/spinlock.h> | ||
| 12 | #include <linux/rcupdate.h> | ||
| 13 | #include <linux/types.h> | ||
| 14 | |||
| 15 | /* | ||
| 16 | * The default fd array needs to be at least BITS_PER_LONG, | ||
| 17 | * as this is the granularity returned by copy_fdset(). | ||
| 18 | */ | ||
| 19 | #define NR_OPEN_DEFAULT BITS_PER_LONG | ||
| 20 | |||
| 21 | /* | ||
| 22 | * The embedded_fd_set is a small fd_set, | ||
| 23 | * suitable for most tasks (which open <= BITS_PER_LONG files) | ||
| 24 | */ | ||
| 25 | struct embedded_fd_set { | ||
| 26 | unsigned long fds_bits[1]; | ||
| 27 | }; | ||
| 28 | |||
| 29 | struct fdtable { | ||
| 30 | unsigned int max_fds; | ||
| 31 | struct file ** fd; /* current fd array */ | ||
| 32 | fd_set *close_on_exec; | ||
| 33 | fd_set *open_fds; | ||
| 34 | struct rcu_head rcu; | ||
| 35 | struct fdtable *next; | ||
| 36 | }; | ||
| 37 | |||
| 38 | /* | ||
| 39 | * Open file table structure | ||
| 40 | */ | ||
| 41 | struct files_struct { | ||
| 42 | /* | ||
| 43 | * read mostly part | ||
| 44 | */ | ||
| 45 | atomic_t count; | ||
| 46 | struct fdtable *fdt; | ||
| 47 | struct fdtable fdtab; | ||
| 48 | /* | ||
| 49 | * written part on a separate cache line in SMP | ||
| 50 | */ | ||
| 51 | spinlock_t file_lock ____cacheline_aligned_in_smp; | ||
| 52 | int next_fd; | ||
| 53 | struct embedded_fd_set close_on_exec_init; | ||
| 54 | struct embedded_fd_set open_fds_init; | ||
| 55 | struct file * fd_array[NR_OPEN_DEFAULT]; | ||
| 56 | }; | ||
| 57 | |||
| 58 | #define files_fdtable(files) (rcu_dereference((files)->fdt)) | ||
| 59 | |||
| 60 | extern struct kmem_cache *filp_cachep; | ||
| 61 | |||
| 62 | struct file_operations; | ||
| 63 | struct vfsmount; | ||
| 64 | struct dentry; | ||
| 65 | |||
| 66 | extern int expand_files(struct files_struct *, int nr); | ||
| 67 | extern void free_fdtable_rcu(struct rcu_head *rcu); | ||
| 68 | extern void __init files_defer_init(void); | ||
| 69 | |||
| 70 | static inline void free_fdtable(struct fdtable *fdt) | ||
| 71 | { | ||
| 72 | call_rcu(&fdt->rcu, free_fdtable_rcu); | ||
| 73 | } | ||
| 74 | |||
| 75 | static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd) | ||
| 76 | { | ||
| 77 | struct file * file = NULL; | ||
| 78 | struct fdtable *fdt = files_fdtable(files); | ||
| 79 | |||
| 80 | if (fd < fdt->max_fds) | ||
| 81 | file = rcu_dereference(fdt->fd[fd]); | ||
| 82 | return file; | ||
| 83 | } | ||
| 84 | |||
| 85 | /* | ||
| 86 | * Check whether the specified fd has an open file. | ||
| 87 | */ | ||
| 88 | #define fcheck(fd) fcheck_files(current->files, fd) | ||
| 89 | |||
| 90 | struct task_struct; | ||
| 91 | |||
| 92 | struct files_struct *get_files_struct(struct task_struct *); | ||
| 93 | void put_files_struct(struct files_struct *fs); | ||
| 94 | void reset_files_struct(struct files_struct *); | ||
| 95 | int unshare_files(struct files_struct **); | ||
| 96 | |||
| 97 | extern struct kmem_cache *files_cachep; | ||
| 98 | |||
| 99 | #endif /* __LINUX_FDTABLE_H */ | ||
