diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/linux/fdtable.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/linux/fdtable.h')
-rw-r--r-- | kernel/include/linux/fdtable.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/kernel/include/linux/fdtable.h b/kernel/include/linux/fdtable.h new file mode 100644 index 000000000..230f87bdf --- /dev/null +++ b/kernel/include/linux/fdtable.h @@ -0,0 +1,118 @@ +/* + * 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; + struct rcu_head rcu; +}; + +static inline bool close_on_exec(int fd, const struct fdtable *fdt) +{ + return test_bit(fd, fdt->close_on_exec); +} + +static inline bool fd_is_open(int fd, const struct fdtable *fdt) +{ + return test_bit(fd, fdt->open_fds); +} + +/* + * Open file table structure + */ +struct files_struct { + /* + * read mostly part + */ + atomic_t count; + struct fdtable __rcu *fdt; + struct fdtable fdtab; + /* + * written part on a separate cache line in SMP + */ + spinlock_t file_lock ____cacheline_aligned_in_smp; + int next_fd; + unsigned long close_on_exec_init[1]; + unsigned long open_fds_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; +} + +static inline struct file *fcheck_files(struct files_struct *files, unsigned int fd) +{ + rcu_lockdep_assert(rcu_read_lock_held() || + lockdep_is_held(&files->file_lock), + "suspicious rcu_dereference_check() usage"); + return __fcheck_files(files, fd); +} + +/* + * 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 *); +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 */ |