file-mmu.c

Go to the documentation of this file.

/* file-mmu.c: ramfs MMU-based file operations
 *
 * Resizable simple ram filesystem for Linux.
 *
 * Copyright (C) 2000 Linus Torvalds.
 *               2000 Transmeta Corp.
 *
 * Usage limits added by David Gibson, Linuxcare Australia.
 * This file is released under the GPL.
 */

/*
 * NOTE! This filesystem is probably most useful
 * not as a real filesystem, but as an example of
 * how virtual filesystems can be written.
 *
 * It doesn't get much simpler than this. Consider
 * that this file implements the full semantics of
 * a POSIX-compliant read-write filesystem.
 *
 * Note in particular how the filesystem does not
 * need to implement any data structures of its own
 * to keep track of the virtual data: using the VFS
 * caches is sufficient.
 */

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/ramfs.h>

#include "internal.h"

const struct address_space_operations ramfs_aops = {
    .readpage   = simple_readpage,
    .write_begin    = simple_write_begin,
    .write_end  = simple_write_end,
    .set_page_dirty = __set_page_dirty_no_writeback,
};

const struct file_operations ramfs_file_operations = {
    .read       = do_sync_read,
    .aio_read   = generic_file_aio_read,
    .write      = do_sync_write,
    .aio_write  = generic_file_aio_write,
    .mmap       = generic_file_mmap,
    .fsync      = noop_fsync,
    .splice_read    = generic_file_splice_read,
    .splice_write   = generic_file_splice_write,
    .llseek     = generic_file_llseek,
};

const struct inode_operations ramfs_file_inode_operations = {
    .setattr    = simple_setattr,
    .getattr    = simple_getattr,
};