LXR linux/fs/ramfs/file-mmu.c

   1/* file-mmu.c: ramfs MMU-based file operations
   2 *
   3 * Resizable simple ram filesystem for Linux.
   4 *
   5 * Copyright (C) 2000 Linus Torvalds.
   6 *               2000 Transmeta Corp.
   7 *
   8 * Usage limits added by David Gibson, Linuxcare Australia.
   9 * This file is released under the GPL.
  10 */
  11
  12/*
  13 * NOTE! This filesystem is probably most useful
  14 * not as a real filesystem, but as an example of
  15 * how virtual filesystems can be written.
  16 *
  17 * It doesn't get much simpler than this. Consider
  18 * that this file implements the full semantics of
  19 * a POSIX-compliant read-write filesystem.
  20 *
  21 * Note in particular how the filesystem does not
  22 * need to implement any data structures of its own
  23 * to keep track of the virtual data: using the VFS
  24 * caches is sufficient.
  25 */
  26
  27#include <linux/fs.h>
  28#include <linux/mm.h>
  29#include <linux/ramfs.h>
  30
  31#include "internal.h"
  32
  33const struct address_space_operations ramfs_aops = {
  34        .readpage       = simple_readpage,
  35        .write_begin    = simple_write_begin,
  36        .write_end      = simple_write_end,
  37        .set_page_dirty = __set_page_dirty_no_writeback,
  38};
  39
  40const struct file_operations ramfs_file_operations = {
  41        .read           = do_sync_read,
  42        .aio_read       = generic_file_aio_read,
  43        .write          = do_sync_write,
  44        .aio_write      = generic_file_aio_write,
  45        .mmap           = generic_file_mmap,
  46        .fsync          = noop_fsync,
  47        .splice_read    = generic_file_splice_read,
  48        .splice_write   = generic_file_splice_write,
  49        .llseek         = generic_file_llseek,
  50};
  51
  52const struct inode_operations ramfs_file_inode_operations = {
  53        .setattr        = simple_setattr,
  54        .getattr        = simple_getattr,
  55};
  56