2 * Optimized MPEG FS - inode and super operations.
3 * Copyright (C) 2006 Bob Copeland <me@bobcopeland.com>
4 * Released under GPL v2.
6 #include <linux/module.h>
7 #include <linux/sched.h>
10 #include <linux/parser.h>
11 #include <linux/buffer_head.h>
12 #include <linux/vmalloc.h>
13 #include <linux/writeback.h>
14 #include <linux/crc-itu-t.h>
17 MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>");
18 MODULE_DESCRIPTION("OMFS (ReplayTV/Karma) Filesystem for Linux");
19 MODULE_LICENSE("GPL");
21 struct inode *omfs_new_inode(struct inode *dir, int mode)
27 struct omfs_sb_info *sbi = OMFS_SB(dir->i_sb);
29 inode = new_inode(dir->i_sb);
31 return ERR_PTR(-ENOMEM);
33 err = omfs_allocate_range(dir->i_sb, sbi->s_mirrors, sbi->s_mirrors,
38 inode->i_ino = new_block;
40 inode->i_uid = current_fsuid();
41 inode->i_gid = current_fsgid();
42 inode->i_mapping->a_ops = &omfs_aops;
44 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
45 switch (mode & S_IFMT) {
47 inode->i_op = &omfs_dir_inops;
48 inode->i_fop = &omfs_dir_operations;
49 inode->i_size = sbi->s_sys_blocksize;
53 inode->i_op = &omfs_file_inops;
54 inode->i_fop = &omfs_file_operations;
59 insert_inode_hash(inode);
60 mark_inode_dirty(inode);
63 make_bad_inode(inode);
69 * Update the header checksums for a dirty inode based on its contents.
70 * Caller is expected to hold the buffer head underlying oi and mark it
73 static void omfs_update_checksums(struct omfs_inode *oi)
75 int xor, i, ofs = 0, count;
77 unsigned char *ptr = (unsigned char *) oi;
79 count = be32_to_cpu(oi->i_head.h_body_size);
80 ofs = sizeof(struct omfs_header);
82 crc = crc_itu_t(crc, ptr + ofs, count);
83 oi->i_head.h_crc = cpu_to_be16(crc);
86 for (i = 1; i < OMFS_XOR_COUNT; i++)
89 oi->i_head.h_check_xor = xor;
92 static int __omfs_write_inode(struct inode *inode, int wait)
94 struct omfs_inode *oi;
95 struct omfs_sb_info *sbi = OMFS_SB(inode->i_sb);
96 struct buffer_head *bh, *bh2;
103 /* get current inode since we may have written sibling ptrs etc. */
104 block = clus_to_blk(sbi, inode->i_ino);
105 bh = sb_bread(inode->i_sb, block);
109 oi = (struct omfs_inode *) bh->b_data;
111 oi->i_head.h_self = cpu_to_be64(inode->i_ino);
112 if (S_ISDIR(inode->i_mode))
113 oi->i_type = OMFS_DIR;
114 else if (S_ISREG(inode->i_mode))
115 oi->i_type = OMFS_FILE;
117 printk(KERN_WARNING "omfs: unknown file type: %d\n",
122 oi->i_head.h_body_size = cpu_to_be32(sbi->s_sys_blocksize -
123 sizeof(struct omfs_header));
124 oi->i_head.h_version = 1;
125 oi->i_head.h_type = OMFS_INODE_NORMAL;
126 oi->i_head.h_magic = OMFS_IMAGIC;
127 oi->i_size = cpu_to_be64(inode->i_size);
129 ctime = inode->i_ctime.tv_sec * 1000LL +
130 ((inode->i_ctime.tv_nsec + 999)/1000);
131 oi->i_ctime = cpu_to_be64(ctime);
133 omfs_update_checksums(oi);
135 mark_buffer_dirty(bh);
137 sync_dirty_buffer(bh);
138 if (buffer_req(bh) && !buffer_uptodate(bh))
142 /* if mirroring writes, copy to next fsblock */
143 for (i = 1; i < sbi->s_mirrors; i++) {
144 bh2 = sb_bread(inode->i_sb, block + i *
145 (sbi->s_blocksize / sbi->s_sys_blocksize));
149 memcpy(bh2->b_data, bh->b_data, bh->b_size);
150 mark_buffer_dirty(bh2);
152 sync_dirty_buffer(bh2);
153 if (buffer_req(bh2) && !buffer_uptodate(bh2))
158 ret = (sync_failed) ? -EIO : 0;
165 static int omfs_write_inode(struct inode *inode, struct writeback_control *wbc)
167 return __omfs_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
170 int omfs_sync_inode(struct inode *inode)
172 return __omfs_write_inode(inode, 1);
176 * called when an entry is deleted, need to clear the bits in the
179 static void omfs_delete_inode(struct inode *inode)
181 truncate_inode_pages(&inode->i_data, 0);
183 if (S_ISREG(inode->i_mode)) {
185 omfs_shrink_inode(inode);
188 omfs_clear_range(inode->i_sb, inode->i_ino, 2);
192 struct inode *omfs_iget(struct super_block *sb, ino_t ino)
194 struct omfs_sb_info *sbi = OMFS_SB(sb);
195 struct omfs_inode *oi;
196 struct buffer_head *bh;
202 inode = iget_locked(sb, ino);
204 return ERR_PTR(-ENOMEM);
205 if (!(inode->i_state & I_NEW))
208 block = clus_to_blk(sbi, ino);
209 bh = sb_bread(inode->i_sb, block);
213 oi = (struct omfs_inode *)bh->b_data;
216 if (ino != be64_to_cpu(oi->i_head.h_self))
219 inode->i_uid = sbi->s_uid;
220 inode->i_gid = sbi->s_gid;
222 ctime = be64_to_cpu(oi->i_ctime);
223 nsecs = do_div(ctime, 1000) * 1000L;
225 inode->i_atime.tv_sec = ctime;
226 inode->i_mtime.tv_sec = ctime;
227 inode->i_ctime.tv_sec = ctime;
228 inode->i_atime.tv_nsec = nsecs;
229 inode->i_mtime.tv_nsec = nsecs;
230 inode->i_ctime.tv_nsec = nsecs;
232 inode->i_mapping->a_ops = &omfs_aops;
234 switch (oi->i_type) {
236 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~sbi->s_dmask);
237 inode->i_op = &omfs_dir_inops;
238 inode->i_fop = &omfs_dir_operations;
239 inode->i_size = sbi->s_sys_blocksize;
243 inode->i_mode = S_IFREG | (S_IRWXUGO & ~sbi->s_fmask);
244 inode->i_fop = &omfs_file_operations;
245 inode->i_size = be64_to_cpu(oi->i_size);
249 unlock_new_inode(inode);
255 return ERR_PTR(-EIO);
258 static void omfs_put_super(struct super_block *sb)
260 struct omfs_sb_info *sbi = OMFS_SB(sb);
263 sb->s_fs_info = NULL;
266 static int omfs_statfs(struct dentry *dentry, struct kstatfs *buf)
268 struct super_block *s = dentry->d_sb;
269 struct omfs_sb_info *sbi = OMFS_SB(s);
270 u64 id = huge_encode_dev(s->s_bdev->bd_dev);
272 buf->f_type = OMFS_MAGIC;
273 buf->f_bsize = sbi->s_blocksize;
274 buf->f_blocks = sbi->s_num_blocks;
275 buf->f_files = sbi->s_num_blocks;
276 buf->f_namelen = OMFS_NAMELEN;
277 buf->f_fsid.val[0] = (u32)id;
278 buf->f_fsid.val[1] = (u32)(id >> 32);
280 buf->f_bfree = buf->f_bavail = buf->f_ffree =
286 static const struct super_operations omfs_sops = {
287 .write_inode = omfs_write_inode,
288 .delete_inode = omfs_delete_inode,
289 .put_super = omfs_put_super,
290 .statfs = omfs_statfs,
291 .show_options = generic_show_options,
295 * For Rio Karma, there is an on-disk free bitmap whose location is
296 * stored in the root block. For ReplayTV, there is no such free bitmap
297 * so we have to walk the tree. Both inodes and file data are allocated
298 * from the same map. This array can be big (300k) so we allocate
299 * in units of the blocksize.
301 static int omfs_get_imap(struct super_block *sb)
306 struct omfs_sb_info *sbi = OMFS_SB(sb);
307 struct buffer_head *bh;
311 bitmap_size = DIV_ROUND_UP(sbi->s_num_blocks, 8);
312 array_size = DIV_ROUND_UP(bitmap_size, sb->s_blocksize);
314 if (sbi->s_bitmap_ino == ~0ULL)
317 sbi->s_imap_size = array_size;
318 sbi->s_imap = kzalloc(array_size * sizeof(unsigned long *), GFP_KERNEL);
322 block = clus_to_blk(sbi, sbi->s_bitmap_ino);
324 for (count = bitmap_size; count > 0; count -= sb->s_blocksize) {
325 bh = sb_bread(sb, block++);
328 *ptr = kmalloc(sb->s_blocksize, GFP_KERNEL);
333 memcpy(*ptr, bh->b_data, sb->s_blocksize);
334 if (count < sb->s_blocksize)
335 memset((void *)*ptr + count, 0xff,
336 sb->s_blocksize - count);
344 for (count = 0; count < array_size; count++)
345 kfree(sbi->s_imap[count]);
350 sbi->s_imap_size = 0;
355 Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask
358 static const match_table_t tokens = {
361 {Opt_umask, "umask=%o"},
362 {Opt_dmask, "dmask=%o"},
363 {Opt_fmask, "fmask=%o"},
366 static int parse_options(char *options, struct omfs_sb_info *sbi)
369 substring_t args[MAX_OPT_ARGS];
375 while ((p = strsep(&options, ",")) != NULL) {
380 token = match_token(p, tokens, args);
383 if (match_int(&args[0], &option))
388 if (match_int(&args[0], &option))
393 if (match_octal(&args[0], &option))
395 sbi->s_fmask = sbi->s_dmask = option;
398 if (match_octal(&args[0], &option))
400 sbi->s_dmask = option;
403 if (match_octal(&args[0], &option))
405 sbi->s_fmask = option;
414 static int omfs_fill_super(struct super_block *sb, void *data, int silent)
416 struct buffer_head *bh, *bh2;
417 struct omfs_super_block *omfs_sb;
418 struct omfs_root_block *omfs_rb;
419 struct omfs_sb_info *sbi;
424 save_mount_options(sb, (char *) data);
426 sbi = kzalloc(sizeof(struct omfs_sb_info), GFP_KERNEL);
432 sbi->s_uid = current_uid();
433 sbi->s_gid = current_gid();
434 sbi->s_dmask = sbi->s_fmask = current_umask();
436 if (!parse_options((char *) data, sbi))
439 sb->s_maxbytes = 0xffffffff;
441 sb_set_blocksize(sb, 0x200);
443 bh = sb_bread(sb, 0);
447 omfs_sb = (struct omfs_super_block *)bh->b_data;
449 if (omfs_sb->s_magic != cpu_to_be32(OMFS_MAGIC)) {
451 printk(KERN_ERR "omfs: Invalid superblock (%x)\n",
455 sb->s_magic = OMFS_MAGIC;
457 sbi->s_num_blocks = be64_to_cpu(omfs_sb->s_num_blocks);
458 sbi->s_blocksize = be32_to_cpu(omfs_sb->s_blocksize);
459 sbi->s_mirrors = be32_to_cpu(omfs_sb->s_mirrors);
460 sbi->s_root_ino = be64_to_cpu(omfs_sb->s_root_block);
461 sbi->s_sys_blocksize = be32_to_cpu(omfs_sb->s_sys_blocksize);
462 mutex_init(&sbi->s_bitmap_lock);
464 if (sbi->s_sys_blocksize > PAGE_SIZE) {
465 printk(KERN_ERR "omfs: sysblock size (%d) is out of range\n",
466 sbi->s_sys_blocksize);
470 if (sbi->s_blocksize < sbi->s_sys_blocksize ||
471 sbi->s_blocksize > OMFS_MAX_BLOCK_SIZE) {
472 printk(KERN_ERR "omfs: block size (%d) is out of range\n",
478 * Use sys_blocksize as the fs block since it is smaller than a
479 * page while the fs blocksize can be larger.
481 sb_set_blocksize(sb, sbi->s_sys_blocksize);
484 * ...and the difference goes into a shift. sys_blocksize is always
485 * a power of two factor of blocksize.
487 sbi->s_block_shift = get_bitmask_order(sbi->s_blocksize) -
488 get_bitmask_order(sbi->s_sys_blocksize);
490 start = clus_to_blk(sbi, be64_to_cpu(omfs_sb->s_root_block));
491 bh2 = sb_bread(sb, start);
495 omfs_rb = (struct omfs_root_block *)bh2->b_data;
497 sbi->s_bitmap_ino = be64_to_cpu(omfs_rb->r_bitmap);
498 sbi->s_clustersize = be32_to_cpu(omfs_rb->r_clustersize);
500 if (sbi->s_num_blocks != be64_to_cpu(omfs_rb->r_num_blocks)) {
501 printk(KERN_ERR "omfs: block count discrepancy between "
502 "super and root blocks (%llx, %llx)\n",
503 (unsigned long long)sbi->s_num_blocks,
504 (unsigned long long)be64_to_cpu(omfs_rb->r_num_blocks));
508 ret = omfs_get_imap(sb);
512 sb->s_op = &omfs_sops;
514 root = omfs_iget(sb, be64_to_cpu(omfs_rb->r_root_dir));
520 sb->s_root = d_alloc_root(root);
525 printk(KERN_DEBUG "omfs: Mounted volume %s\n", omfs_rb->r_name);
536 static int omfs_get_sb(struct file_system_type *fs_type,
537 int flags, const char *dev_name,
538 void *data, struct vfsmount *m)
540 return get_sb_bdev(fs_type, flags, dev_name, data, omfs_fill_super, m);
543 static struct file_system_type omfs_fs_type = {
544 .owner = THIS_MODULE,
546 .get_sb = omfs_get_sb,
547 .kill_sb = kill_block_super,
548 .fs_flags = FS_REQUIRES_DEV,
551 static int __init init_omfs_fs(void)
553 return register_filesystem(&omfs_fs_type);
556 static void __exit exit_omfs_fs(void)
558 unregister_filesystem(&omfs_fs_type);
561 module_init(init_omfs_fs);
562 module_exit(exit_omfs_fs);