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-rw-r--r--include/linux/file.h84
1 files changed, 84 insertions, 0 deletions
diff --git a/include/linux/file.h b/include/linux/file.h
new file mode 100644
index 000000000000..5206beb9a80e
--- /dev/null
+++ b/include/linux/file.h
@@ -0,0 +1,84 @@
+/*
+ * Wrapper functions for accessing the file_struct fd array.
+ */
+
+#ifndef __LINUX_FILE_H
+#define __LINUX_FILE_H
+
+#include <asm/atomic.h>
+#include <linux/posix_types.h>
+#include <linux/compiler.h>
+#include <linux/spinlock.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
+
+/*
+ * Open file table structure
+ */
+struct files_struct {
+ atomic_t count;
+ spinlock_t file_lock; /* Protects all the below members. Nests inside tsk->alloc_lock */
+ int max_fds;
+ int max_fdset;
+ int next_fd;
+ struct file ** fd; /* current fd array */
+ fd_set *close_on_exec;
+ fd_set *open_fds;
+ fd_set close_on_exec_init;
+ fd_set open_fds_init;
+ struct file * fd_array[NR_OPEN_DEFAULT];
+};
+
+extern void FASTCALL(__fput(struct file *));
+extern void FASTCALL(fput(struct file *));
+
+static inline void fput_light(struct file *file, int fput_needed)
+{
+ if (unlikely(fput_needed))
+ fput(file);
+}
+
+extern struct file * FASTCALL(fget(unsigned int fd));
+extern struct file * FASTCALL(fget_light(unsigned int fd, int *fput_needed));
+extern void FASTCALL(set_close_on_exec(unsigned int fd, int flag));
+extern void put_filp(struct file *);
+extern int get_unused_fd(void);
+extern void FASTCALL(put_unused_fd(unsigned int fd));
+struct kmem_cache_s;
+extern void filp_ctor(void * objp, struct kmem_cache_s *cachep, unsigned long cflags);
+extern void filp_dtor(void * objp, struct kmem_cache_s *cachep, unsigned long dflags);
+
+extern struct file ** alloc_fd_array(int);
+extern void free_fd_array(struct file **, int);
+
+extern fd_set *alloc_fdset(int);
+extern void free_fdset(fd_set *, int);
+
+extern int expand_files(struct files_struct *, int nr);
+
+static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd)
+{
+ struct file * file = NULL;
+
+ if (fd < files->max_fds)
+ file = files->fd[fd];
+ return file;
+}
+
+/*
+ * Check whether the specified fd has an open file.
+ */
+#define fcheck(fd) fcheck_files(current->files, fd)
+
+extern void FASTCALL(fd_install(unsigned int fd, struct file * file));
+
+struct task_struct;
+
+struct files_struct *get_files_struct(struct task_struct *);
+void FASTCALL(put_files_struct(struct files_struct *fs));
+
+#endif /* __LINUX_FILE_H */