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/version.h>
7 #include <linux/module.h>
8 #include <linux/sched.h>
10 #include <linux/vfs.h>
11 #include <linux/parser.h>
12 #include <linux/buffer_head.h>
13 #include <linux/vmalloc.h>
14 #include <linux/writeback.h>
15 #include <linux/crc-itu-t.h>
18 MODULE_AUTHOR("Bob Copeland <me@bobcopeland.com>");
19 MODULE_DESCRIPTION("OMFS (ReplayTV/Karma) Filesystem for Linux");
20 MODULE_LICENSE("GPL");
22 struct inode *omfs_new_inode(struct inode *dir, int mode)
28 struct omfs_sb_info *sbi = OMFS_SB(dir->i_sb);
30 inode = new_inode(dir->i_sb);
32 return ERR_PTR(-ENOMEM);
34 err = omfs_allocate_range(dir->i_sb, sbi->s_mirrors, sbi->s_mirrors,
39 inode->i_ino = new_block;
41 inode->i_uid = current_fsuid();
42 inode->i_gid = current_fsgid();
43 inode->i_mapping->a_ops = &omfs_aops;
45 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
46 switch (mode & S_IFMT) {
48 inode->i_op = &omfs_dir_inops;
49 inode->i_fop = &omfs_dir_operations;
50 inode->i_size = sbi->s_sys_blocksize;
54 inode->i_op = &omfs_file_inops;
55 inode->i_fop = &omfs_file_operations;
60 insert_inode_hash(inode);
61 mark_inode_dirty(inode);
64 make_bad_inode(inode);
70 * Update the header checksums for a dirty inode based on its contents.
71 * Caller is expected to hold the buffer head underlying oi and mark it
74 static void omfs_update_checksums(struct omfs_inode *oi)
76 int xor, i, ofs = 0, count;
78 unsigned char *ptr = (unsigned char *) oi;
80 count = be32_to_cpu(oi->i_head.h_body_size);
81 ofs = sizeof(struct omfs_header);
83 crc = crc_itu_t(crc, ptr + ofs, count);
84 oi->i_head.h_crc = cpu_to_be16(crc);
87 for (i = 1; i < OMFS_XOR_COUNT; i++)
90 oi->i_head.h_check_xor = xor;
93 static int __omfs_write_inode(struct inode *inode, int wait)
95 struct omfs_inode *oi;
96 struct omfs_sb_info *sbi = OMFS_SB(inode->i_sb);
97 struct buffer_head *bh, *bh2;
104 /* get current inode since we may have written sibling ptrs etc. */
105 block = clus_to_blk(sbi, inode->i_ino);
106 bh = sb_bread(inode->i_sb, block);
110 oi = (struct omfs_inode *) bh->b_data;
112 oi->i_head.h_self = cpu_to_be64(inode->i_ino);
113 if (S_ISDIR(inode->i_mode))
114 oi->i_type = OMFS_DIR;
115 else if (S_ISREG(inode->i_mode))
116 oi->i_type = OMFS_FILE;
118 printk(KERN_WARNING "omfs: unknown file type: %d\n",
123 oi->i_head.h_body_size = cpu_to_be32(sbi->s_sys_blocksize -
124 sizeof(struct omfs_header));
125 oi->i_head.h_version = 1;
126 oi->i_head.h_type = OMFS_INODE_NORMAL;
127 oi->i_head.h_magic = OMFS_IMAGIC;
128 oi->i_size = cpu_to_be64(inode->i_size);
130 ctime = inode->i_ctime.tv_sec * 1000LL +
131 ((inode->i_ctime.tv_nsec + 999)/1000);
132 oi->i_ctime = cpu_to_be64(ctime);
134 omfs_update_checksums(oi);
136 mark_buffer_dirty(bh);
138 sync_dirty_buffer(bh);
139 if (buffer_req(bh) && !buffer_uptodate(bh))
143 /* if mirroring writes, copy to next fsblock */
144 for (i = 1; i < sbi->s_mirrors; i++) {
145 bh2 = sb_bread(inode->i_sb, block + i *
146 (sbi->s_blocksize / sbi->s_sys_blocksize));
150 memcpy(bh2->b_data, bh->b_data, bh->b_size);
151 mark_buffer_dirty(bh2);
153 sync_dirty_buffer(bh2);
154 if (buffer_req(bh2) && !buffer_uptodate(bh2))
159 ret = (sync_failed) ? -EIO : 0;
166 static int omfs_write_inode(struct inode *inode, struct writeback_control *wbc)
168 return __omfs_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
171 int omfs_sync_inode(struct inode *inode)
173 return __omfs_write_inode(inode, 1);
177 * called when an entry is deleted, need to clear the bits in the
180 static void omfs_delete_inode(struct inode *inode)
182 truncate_inode_pages(&inode->i_data, 0);
184 if (S_ISREG(inode->i_mode)) {
186 omfs_shrink_inode(inode);
189 omfs_clear_range(inode->i_sb, inode->i_ino, 2);
193 struct inode *omfs_iget(struct super_block *sb, ino_t ino)
195 struct omfs_sb_info *sbi = OMFS_SB(sb);
196 struct omfs_inode *oi;
197 struct buffer_head *bh;
203 inode = iget_locked(sb, ino);
205 return ERR_PTR(-ENOMEM);
206 if (!(inode->i_state & I_NEW))
209 block = clus_to_blk(sbi, ino);
210 bh = sb_bread(inode->i_sb, block);
214 oi = (struct omfs_inode *)bh->b_data;
217 if (ino != be64_to_cpu(oi->i_head.h_self))
220 inode->i_uid = sbi->s_uid;
221 inode->i_gid = sbi->s_gid;
223 ctime = be64_to_cpu(oi->i_ctime);
224 nsecs = do_div(ctime, 1000) * 1000L;
226 inode->i_atime.tv_sec = ctime;
227 inode->i_mtime.tv_sec = ctime;
228 inode->i_ctime.tv_sec = ctime;
229 inode->i_atime.tv_nsec = nsecs;
230 inode->i_mtime.tv_nsec = nsecs;
231 inode->i_ctime.tv_nsec = nsecs;
233 inode->i_mapping->a_ops = &omfs_aops;
235 switch (oi->i_type) {
237 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~sbi->s_dmask);
238 inode->i_op = &omfs_dir_inops;
239 inode->i_fop = &omfs_dir_operations;
240 inode->i_size = sbi->s_sys_blocksize;
244 inode->i_mode = S_IFREG | (S_IRWXUGO & ~sbi->s_fmask);
245 inode->i_fop = &omfs_file_operations;
246 inode->i_size = be64_to_cpu(oi->i_size);
250 unlock_new_inode(inode);
256 return ERR_PTR(-EIO);
259 static void omfs_put_super(struct super_block *sb)
261 struct omfs_sb_info *sbi = OMFS_SB(sb);
264 sb->s_fs_info = NULL;
267 static int omfs_statfs(struct dentry *dentry, struct kstatfs *buf)
269 struct super_block *s = dentry->d_sb;
270 struct omfs_sb_info *sbi = OMFS_SB(s);
271 u64 id = huge_encode_dev(s->s_bdev->bd_dev);
273 buf->f_type = OMFS_MAGIC;
274 buf->f_bsize = sbi->s_blocksize;
275 buf->f_blocks = sbi->s_num_blocks;
276 buf->f_files = sbi->s_num_blocks;
277 buf->f_namelen = OMFS_NAMELEN;
278 buf->f_fsid.val[0] = (u32)id;
279 buf->f_fsid.val[1] = (u32)(id >> 32);
281 buf->f_bfree = buf->f_bavail = buf->f_ffree =
287 static const struct super_operations omfs_sops = {
288 .write_inode = omfs_write_inode,
289 .delete_inode = omfs_delete_inode,
290 .put_super = omfs_put_super,
291 .statfs = omfs_statfs,
292 .show_options = generic_show_options,
296 * For Rio Karma, there is an on-disk free bitmap whose location is
297 * stored in the root block. For ReplayTV, there is no such free bitmap
298 * so we have to walk the tree. Both inodes and file data are allocated
299 * from the same map. This array can be big (300k) so we allocate
300 * in units of the blocksize.
302 static int omfs_get_imap(struct super_block *sb)
307 struct omfs_sb_info *sbi = OMFS_SB(sb);
308 struct buffer_head *bh;
312 bitmap_size = DIV_ROUND_UP(sbi->s_num_blocks, 8);
313 array_size = DIV_ROUND_UP(bitmap_size, sb->s_blocksize);
315 if (sbi->s_bitmap_ino == ~0ULL)
318 sbi->s_imap_size = array_size;
319 sbi->s_imap = kzalloc(array_size * sizeof(unsigned long *), GFP_KERNEL);
323 block = clus_to_blk(sbi, sbi->s_bitmap_ino);
325 for (count = bitmap_size; count > 0; count -= sb->s_blocksize) {
326 bh = sb_bread(sb, block++);
329 *ptr = kmalloc(sb->s_blocksize, GFP_KERNEL);
334 memcpy(*ptr, bh->b_data, sb->s_blocksize);
335 if (count < sb->s_blocksize)
336 memset((void *)*ptr + count, 0xff,
337 sb->s_blocksize - count);
345 for (count = 0; count < array_size; count++)
346 kfree(sbi->s_imap[count]);
351 sbi->s_imap_size = 0;
356 Opt_uid, Opt_gid, Opt_umask, Opt_dmask, Opt_fmask
359 static const match_table_t tokens = {
362 {Opt_umask, "umask=%o"},
363 {Opt_dmask, "dmask=%o"},
364 {Opt_fmask, "fmask=%o"},
367 static int parse_options(char *options, struct omfs_sb_info *sbi)
370 substring_t args[MAX_OPT_ARGS];
376 while ((p = strsep(&options, ",")) != NULL) {
381 token = match_token(p, tokens, args);
384 if (match_int(&args[0], &option))
389 if (match_int(&args[0], &option))
394 if (match_octal(&args[0], &option))
396 sbi->s_fmask = sbi->s_dmask = option;
399 if (match_octal(&args[0], &option))
401 sbi->s_dmask = option;
404 if (match_octal(&args[0], &option))
406 sbi->s_fmask = option;
415 static int omfs_fill_super(struct super_block *sb, void *data, int silent)
417 struct buffer_head *bh, *bh2;
418 struct omfs_super_block *omfs_sb;
419 struct omfs_root_block *omfs_rb;
420 struct omfs_sb_info *sbi;
425 save_mount_options(sb, (char *) data);
427 sbi = kzalloc(sizeof(struct omfs_sb_info), GFP_KERNEL);
433 sbi->s_uid = current_uid();
434 sbi->s_gid = current_gid();
435 sbi->s_dmask = sbi->s_fmask = current_umask();
437 if (!parse_options((char *) data, sbi))
440 sb->s_maxbytes = 0xffffffff;
442 sb_set_blocksize(sb, 0x200);
444 bh = sb_bread(sb, 0);
448 omfs_sb = (struct omfs_super_block *)bh->b_data;
450 if (omfs_sb->s_magic != cpu_to_be32(OMFS_MAGIC)) {
452 printk(KERN_ERR "omfs: Invalid superblock (%x)\n",
456 sb->s_magic = OMFS_MAGIC;
458 sbi->s_num_blocks = be64_to_cpu(omfs_sb->s_num_blocks);
459 sbi->s_blocksize = be32_to_cpu(omfs_sb->s_blocksize);
460 sbi->s_mirrors = be32_to_cpu(omfs_sb->s_mirrors);
461 sbi->s_root_ino = be64_to_cpu(omfs_sb->s_root_block);
462 sbi->s_sys_blocksize = be32_to_cpu(omfs_sb->s_sys_blocksize);
463 mutex_init(&sbi->s_bitmap_lock);
465 if (sbi->s_sys_blocksize > PAGE_SIZE) {
466 printk(KERN_ERR "omfs: sysblock size (%d) is out of range\n",
467 sbi->s_sys_blocksize);
471 if (sbi->s_blocksize < sbi->s_sys_blocksize ||
472 sbi->s_blocksize > OMFS_MAX_BLOCK_SIZE) {
473 printk(KERN_ERR "omfs: block size (%d) is out of range\n",
479 * Use sys_blocksize as the fs block since it is smaller than a
480 * page while the fs blocksize can be larger.
482 sb_set_blocksize(sb, sbi->s_sys_blocksize);
485 * ...and the difference goes into a shift. sys_blocksize is always
486 * a power of two factor of blocksize.
488 sbi->s_block_shift = get_bitmask_order(sbi->s_blocksize) -
489 get_bitmask_order(sbi->s_sys_blocksize);
491 start = clus_to_blk(sbi, be64_to_cpu(omfs_sb->s_root_block));
492 bh2 = sb_bread(sb, start);
496 omfs_rb = (struct omfs_root_block *)bh2->b_data;
498 sbi->s_bitmap_ino = be64_to_cpu(omfs_rb->r_bitmap);
499 sbi->s_clustersize = be32_to_cpu(omfs_rb->r_clustersize);
501 if (sbi->s_num_blocks != be64_to_cpu(omfs_rb->r_num_blocks)) {
502 printk(KERN_ERR "omfs: block count discrepancy between "
503 "super and root blocks (%llx, %llx)\n",
504 (unsigned long long)sbi->s_num_blocks,
505 (unsigned long long)be64_to_cpu(omfs_rb->r_num_blocks));
509 ret = omfs_get_imap(sb);
513 sb->s_op = &omfs_sops;
515 root = omfs_iget(sb, be64_to_cpu(omfs_rb->r_root_dir));
521 sb->s_root = d_alloc_root(root);
526 printk(KERN_DEBUG "omfs: Mounted volume %s\n", omfs_rb->r_name);
537 static int omfs_get_sb(struct file_system_type *fs_type,
538 int flags, const char *dev_name,
539 void *data, struct vfsmount *m)
541 return get_sb_bdev(fs_type, flags, dev_name, data, omfs_fill_super, m);
544 static struct file_system_type omfs_fs_type = {
545 .owner = THIS_MODULE,
547 .get_sb = omfs_get_sb,
548 .kill_sb = kill_block_super,
549 .fs_flags = FS_REQUIRES_DEV,
552 static int __init init_omfs_fs(void)
554 return register_filesystem(&omfs_fs_type);
557 static void __exit exit_omfs_fs(void)
559 unregister_filesystem(&omfs_fs_type);
562 module_init(init_omfs_fs);
563 module_exit(exit_omfs_fs);