1 #include <linux/module.h>
2 #include <linux/buffer_head.h>
4 #include <linux/pagemap.h>
5 #include <linux/highmem.h>
6 #include <linux/time.h>
7 #include <linux/init.h>
8 #include <linux/string.h>
9 #include <linux/smp_lock.h>
10 #include <linux/backing-dev.h>
13 #include "transaction.h"
15 #define BTRFS_SUPER_MAGIC 0x9123682E
17 static struct inode_operations btrfs_dir_inode_operations;
18 static struct super_operations btrfs_super_ops;
19 static struct file_operations btrfs_dir_file_operations;
22 /* some random number */
24 static struct super_operations ramfs_ops;
26 static struct backing_dev_info ramfs_backing_dev_info = {
27 .ra_pages = 0, /* No readahead */
28 .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK |
29 BDI_CAP_MAP_DIRECT | BDI_CAP_MAP_COPY |
30 BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP,
33 struct inode *ramfs_get_inode(struct super_block *sb, int mode, dev_t dev)
35 struct inode * inode = new_inode(sb);
39 inode->i_uid = current->fsuid;
40 inode->i_gid = current->fsgid;
42 inode->i_mapping->a_ops = &ramfs_aops;
43 inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
44 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
45 switch (mode & S_IFMT) {
47 init_special_inode(inode, mode, dev);
50 inode->i_op = &ramfs_file_inode_operations;
51 inode->i_fop = &ramfs_file_operations;
54 inode->i_op = &ramfs_dir_inode_operations;
55 inode->i_fop = &simple_dir_operations;
57 /* directory inodes start off with i_nlink == 2 (for "." entry) */
61 inode->i_op = &page_symlink_inode_operations;
69 * File creation. Allocate an inode, and we're done..
73 ramfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
75 struct inode * inode = ramfs_get_inode(dir->i_sb, mode, dev);
79 if (dir->i_mode & S_ISGID) {
80 inode->i_gid = dir->i_gid;
82 inode->i_mode |= S_ISGID;
84 d_instantiate(dentry, inode);
85 dget(dentry); /* Extra count - pin the dentry in core */
87 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
92 static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
94 int retval = ramfs_mknod(dir, dentry, mode | S_IFDIR, 0);
100 static int ramfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd)
102 return ramfs_mknod(dir, dentry, mode | S_IFREG, 0);
105 static int ramfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
110 inode = ramfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
112 int l = strlen(symname)+1;
113 error = page_symlink(inode, symname, l);
115 if (dir->i_mode & S_ISGID)
116 inode->i_gid = dir->i_gid;
117 d_instantiate(dentry, inode);
119 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
126 static struct inode_operations ramfs_dir_inode_operations = {
127 .create = ramfs_create,
128 .lookup = simple_lookup,
130 .unlink = simple_unlink,
131 .symlink = ramfs_symlink,
132 .mkdir = ramfs_mkdir,
133 .rmdir = simple_rmdir,
134 .mknod = ramfs_mknod,
135 .rename = simple_rename,
139 static void btrfs_read_locked_inode(struct inode *inode)
141 struct btrfs_path path;
142 struct btrfs_inode_item *inode_item;
143 struct btrfs_root *root = btrfs_sb(inode->i_sb);
145 btrfs_init_path(&path);
146 ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
148 make_bad_inode(inode);
151 inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
153 struct btrfs_inode_item);
155 inode->i_mode = btrfs_inode_mode(inode_item);
156 inode->i_nlink = btrfs_inode_nlink(inode_item);
157 inode->i_uid = btrfs_inode_uid(inode_item);
158 inode->i_gid = btrfs_inode_gid(inode_item);
159 inode->i_size = btrfs_inode_size(inode_item);
160 inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
161 inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
162 inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
163 inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
164 inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
165 inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
166 inode->i_blocks = btrfs_inode_nblocks(inode_item);
167 inode->i_generation = btrfs_inode_generation(inode_item);
168 btrfs_release_path(root, &path);
169 switch (inode->i_mode & S_IFMT) {
172 init_special_inode(inode, inode->i_mode,
173 btrfs_inode_rdev(inode_item));
179 inode->i_op = &btrfs_dir_inode_operations;
180 inode->i_fop = &btrfs_dir_file_operations;
183 // inode->i_op = &page_symlink_inode_operations;
189 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
192 const char *name = dentry->d_name.name;
193 int namelen = dentry->d_name.len;
194 struct btrfs_dir_item *di;
195 struct btrfs_path path;
196 struct btrfs_root *root = btrfs_sb(dir->i_sb);
199 btrfs_init_path(&path);
200 ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
202 if (ret || !btrfs_match_dir_item_name(root, &path, name, namelen)) {
206 di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
207 struct btrfs_dir_item);
208 *ino = btrfs_dir_objectid(di);
210 btrfs_release_path(root, &path);
214 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
215 struct nameidata *nd)
217 struct inode * inode;
221 if (dentry->d_name.len > BTRFS_NAME_LEN)
222 return ERR_PTR(-ENAMETOOLONG);
224 ret = btrfs_inode_by_name(dir, dentry, &ino);
229 inode = iget(dir->i_sb, ino);
231 return ERR_PTR(-EACCES);
233 return d_splice_alias(inode, dentry);
236 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
238 struct inode *inode = filp->f_path.dentry->d_inode;
239 struct btrfs_root *root = btrfs_sb(inode->i_sb);
240 struct btrfs_item *item;
241 struct btrfs_dir_item *di;
242 struct btrfs_key key;
243 struct btrfs_path path;
246 struct btrfs_leaf *leaf;
249 unsigned char d_type = DT_UNKNOWN;
252 key.objectid = inode->i_ino;
254 btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
255 key.offset = filp->f_pos;
256 btrfs_init_path(&path);
257 ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
263 leaf = btrfs_buffer_leaf(path.nodes[0]);
264 nritems = btrfs_header_nritems(&leaf->header);
265 slot = path.slots[0];
267 if (slot == nritems -1) {
268 ret = btrfs_next_leaf(root, &path);
271 leaf = btrfs_buffer_leaf(path.nodes[0]);
272 nritems = btrfs_header_nritems(&leaf->header);
273 slot = path.slots[0];
280 item = leaf->items + slot;
281 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
283 if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
285 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
287 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
288 over = filldir(dirent, (const char *)(di + 1),
289 btrfs_dir_name_len(di),
290 btrfs_disk_key_offset(&item->key),
291 btrfs_dir_objectid(di), d_type);
293 filp->f_pos = btrfs_disk_key_offset(&item->key);
296 filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
300 btrfs_release_path(root, &path);
304 static void btrfs_put_super (struct super_block * sb)
306 struct btrfs_root *root = btrfs_sb(sb);
309 ret = close_ctree(root);
311 printk("close ctree returns %d\n", ret);
313 sb->s_fs_info = NULL;
316 static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
318 struct inode * inode;
319 struct dentry * root_dentry;
320 struct btrfs_super_block *disk_super;
321 struct buffer_head *bh;
322 struct btrfs_root *root;
324 sb->s_maxbytes = MAX_LFS_FILESIZE;
325 sb->s_blocksize = PAGE_CACHE_SIZE;
326 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
327 sb->s_magic = BTRFS_SUPER_MAGIC;
328 sb->s_op = &btrfs_super_ops;
331 bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
333 printk("btrfs: unable to read on disk super\n");
336 disk_super = (struct btrfs_super_block *)bh->b_data;
337 root = open_ctree(sb, bh, disk_super);
338 sb->s_fs_info = root;
340 printk("btrfs: open_ctree failed\n");
343 printk("read in super total blocks %Lu root %Lu\n",
344 btrfs_super_total_blocks(disk_super),
345 btrfs_super_root_dir(disk_super));
347 inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
350 if (inode->i_state & I_NEW) {
351 btrfs_read_locked_inode(inode);
352 unlock_new_inode(inode);
355 root_dentry = d_alloc_root(inode);
360 sb->s_root = root_dentry;
365 static void fill_inode_item(struct btrfs_inode_item *item,
368 btrfs_set_inode_uid(item, inode->i_uid);
369 btrfs_set_inode_gid(item, inode->i_gid);
370 btrfs_set_inode_size(item, inode->i_size);
371 btrfs_set_inode_mode(item, inode->i_mode);
372 btrfs_set_inode_nlink(item, inode->i_nlink);
373 btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
374 btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
375 btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
376 btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
377 btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
378 btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
379 btrfs_set_inode_nblocks(item, inode->i_blocks);
380 btrfs_set_inode_generation(item, inode->i_generation);
383 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
384 struct inode *dir, int mode)
387 struct btrfs_inode_item inode_item;
388 struct btrfs_root *root = btrfs_sb(dir->i_sb);
389 struct btrfs_key key;
393 inode = new_inode(dir->i_sb);
395 return ERR_PTR(-ENOMEM);
397 ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
400 inode->i_uid = current->fsuid;
401 inode->i_gid = current->fsgid;
402 inode->i_mode = mode;
403 inode->i_ino = objectid;
405 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
406 fill_inode_item(&inode_item, inode);
409 key.objectid = objectid;
412 btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
413 ret = btrfs_insert_inode_map(trans, root, objectid, &key);
416 ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
419 insert_inode_hash(inode);
420 // FIXME mark_inode_dirty(inode)
424 static int btrfs_add_link(struct btrfs_trans_handle *trans,
425 struct dentry *dentry, struct inode *inode)
428 ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
429 dentry->d_name.name, dentry->d_name.len,
430 dentry->d_parent->d_inode->i_ino,
435 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
436 struct dentry *dentry, struct inode *inode)
438 int err = btrfs_add_link(trans, dentry, inode);
440 d_instantiate(dentry, inode);
443 inode_dec_link_count(inode);
448 static int btrfs_create(struct inode *dir, struct dentry *dentry,
449 int mode, struct nameidata *nd)
451 struct btrfs_trans_handle *trans;
452 struct btrfs_root *root = btrfs_sb(dir->i_sb);
456 mutex_lock(&root->fs_info->fs_mutex);
457 trans = btrfs_start_transaction(root, 1);
458 inode = btrfs_new_inode(trans, dir, mode);
459 err = PTR_ERR(inode);
462 // FIXME mark the inode dirty
463 err = btrfs_add_nondir(trans, dentry, inode);
464 dir->i_sb->s_dirt = 1;
465 btrfs_end_transaction(trans, root);
467 mutex_unlock(&root->fs_info->fs_mutex);
471 static int btrfs_sync_fs(struct super_block *sb, int wait)
473 struct btrfs_trans_handle *trans;
474 struct btrfs_root *root;
479 filemap_flush(sb->s_bdev->bd_inode->i_mapping);
482 filemap_write_and_wait(sb->s_bdev->bd_inode->i_mapping);
485 mutex_lock(&root->fs_info->fs_mutex);
486 trans = btrfs_start_transaction(root, 1);
487 ret = btrfs_commit_transaction(trans, root);
490 printk("btrfs sync_fs\n");
491 mutex_unlock(&root->fs_info->fs_mutex);
495 static void btrfs_write_super(struct super_block *sb)
497 btrfs_sync_fs(sb, 1);
501 static int btrfs_get_sb(struct file_system_type *fs_type,
502 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
504 return get_sb_bdev(fs_type, flags, dev_name, data,
505 btrfs_fill_super, mnt);
508 static struct file_system_type btrfs_fs_type = {
509 .owner = THIS_MODULE,
511 .get_sb = btrfs_get_sb,
512 .kill_sb = kill_block_super,
513 .fs_flags = FS_REQUIRES_DEV,
516 static struct super_operations btrfs_super_ops = {
517 .statfs = simple_statfs,
518 .drop_inode = generic_delete_inode,
519 .put_super = btrfs_put_super,
520 .read_inode = btrfs_read_locked_inode,
521 .write_super = btrfs_write_super,
522 .sync_fs = btrfs_sync_fs,
525 static struct inode_operations btrfs_dir_inode_operations = {
526 .lookup = btrfs_lookup,
527 .create = btrfs_create,
530 static struct file_operations btrfs_dir_file_operations = {
531 .llseek = generic_file_llseek,
532 .read = generic_read_dir,
533 .readdir = btrfs_readdir,
537 static int __init init_btrfs_fs(void)
539 printk("btrfs loaded!\n");
540 return register_filesystem(&btrfs_fs_type);
543 static void __exit exit_btrfs_fs(void)
545 unregister_filesystem(&btrfs_fs_type);
546 printk("btrfs unloaded\n");
549 module_init(init_btrfs_fs)
550 module_exit(exit_btrfs_fs)
552 MODULE_LICENSE("GPL");