1 /* file-mmu.c: ramfs MMU-based file operations 1 /* file-mmu.c: ramfs MMU-based file operations
2 * 2 *
3 * Resizable simple ram filesystem for Linux. 3 * Resizable simple ram filesystem for Linux.
4 * 4 *
5 * Copyright (C) 2000 Linus Torvalds. 5 * Copyright (C) 2000 Linus Torvalds.
6 * 2000 Transmeta Corp. 6 * 2000 Transmeta Corp.
7 * 7 *
8 * Usage limits added by David Gibson, Linuxca 8 * Usage limits added by David Gibson, Linuxcare Australia.
9 * This file is released under the GPL. 9 * This file is released under the GPL.
10 */ 10 */
11 11
12 /* 12 /*
13 * NOTE! This filesystem is probably most usef 13 * NOTE! This filesystem is probably most useful
14 * not as a real filesystem, but as an example 14 * not as a real filesystem, but as an example of
15 * how virtual filesystems can be written. 15 * how virtual filesystems can be written.
16 * 16 *
17 * It doesn't get much simpler than this. Cons 17 * It doesn't get much simpler than this. Consider
18 * that this file implements the full semantic 18 * that this file implements the full semantics of
19 * a POSIX-compliant read-write filesystem. 19 * a POSIX-compliant read-write filesystem.
20 * 20 *
21 * Note in particular how the filesystem does 21 * Note in particular how the filesystem does not
22 * need to implement any data structures of it 22 * need to implement any data structures of its own
23 * to keep track of the virtual data: using th 23 * to keep track of the virtual data: using the VFS
24 * caches is sufficient. 24 * caches is sufficient.
25 */ 25 */
26 26
27 #include <linux/fs.h> 27 #include <linux/fs.h>
28 #include <linux/mm.h> 28 #include <linux/mm.h>
29 #include <linux/ramfs.h> 29 #include <linux/ramfs.h>
30 #include <linux/sched.h> <<
31 30
32 #include "internal.h" 31 #include "internal.h"
33 32
34 static unsigned long ramfs_mmu_get_unmapped_ar <<
35 unsigned long addr, unsigned l <<
36 unsigned long flags) <<
37 { <<
38 return mm_get_unmapped_area(current->m <<
39 } <<
40 <<
41 const struct file_operations ramfs_file_operat 33 const struct file_operations ramfs_file_operations = {
42 .read_iter = generic_file_read_it 34 .read_iter = generic_file_read_iter,
43 .write_iter = generic_file_write_i 35 .write_iter = generic_file_write_iter,
44 .mmap = generic_file_mmap, 36 .mmap = generic_file_mmap,
45 .fsync = noop_fsync, 37 .fsync = noop_fsync,
46 .splice_read = filemap_splice_read, !! 38 .splice_read = generic_file_splice_read,
47 .splice_write = iter_file_splice_wri 39 .splice_write = iter_file_splice_write,
48 .llseek = generic_file_llseek, 40 .llseek = generic_file_llseek,
49 .get_unmapped_area = ramfs_mmu_ge <<
50 }; 41 };
51 42
52 const struct inode_operations ramfs_file_inode 43 const struct inode_operations ramfs_file_inode_operations = {
53 .setattr = simple_setattr, 44 .setattr = simple_setattr,
54 .getattr = simple_getattr, 45 .getattr = simple_getattr,
55 }; 46 };
56 47
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