Btrfs: symlinks and hard links
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Родитель
e06afa839e
Коммит
2b8d99a723
163
fs/btrfs/super.c
163
fs/btrfs/super.c
|
@ -26,11 +26,13 @@ struct btrfs_iget_args {
|
|||
#define BTRFS_SUPER_MAGIC 0x9123682E
|
||||
|
||||
static struct inode_operations btrfs_dir_inode_operations;
|
||||
static struct inode_operations btrfs_symlink_inode_operations;
|
||||
static struct inode_operations btrfs_dir_ro_inode_operations;
|
||||
static struct super_operations btrfs_super_ops;
|
||||
static struct file_operations btrfs_dir_file_operations;
|
||||
static struct inode_operations btrfs_file_inode_operations;
|
||||
static struct address_space_operations btrfs_aops;
|
||||
static struct address_space_operations btrfs_symlink_aops;
|
||||
static struct file_operations btrfs_file_operations;
|
||||
|
||||
static void btrfs_read_locked_inode(struct inode *inode)
|
||||
|
@ -103,7 +105,8 @@ static void btrfs_read_locked_inode(struct inode *inode)
|
|||
inode->i_op = &btrfs_dir_inode_operations;
|
||||
break;
|
||||
case S_IFLNK:
|
||||
// inode->i_op = &page_symlink_inode_operations;
|
||||
inode->i_op = &btrfs_symlink_inode_operations;
|
||||
inode->i_mapping->a_ops = &btrfs_symlink_aops;
|
||||
break;
|
||||
}
|
||||
return;
|
||||
|
@ -940,6 +943,41 @@ out_unlock:
|
|||
return err;
|
||||
}
|
||||
|
||||
static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
|
||||
struct dentry *dentry)
|
||||
{
|
||||
struct btrfs_trans_handle *trans;
|
||||
struct btrfs_root *root = BTRFS_I(dir)->root;
|
||||
struct inode *inode = old_dentry->d_inode;
|
||||
int err;
|
||||
int drop_inode = 0;
|
||||
|
||||
if (inode->i_nlink == 0)
|
||||
return -ENOENT;
|
||||
|
||||
inc_nlink(inode);
|
||||
mutex_lock(&root->fs_info->fs_mutex);
|
||||
trans = btrfs_start_transaction(root, 1);
|
||||
btrfs_set_trans_block_group(trans, dir);
|
||||
atomic_inc(&inode->i_count);
|
||||
err = btrfs_add_nondir(trans, dentry, inode);
|
||||
if (err)
|
||||
drop_inode = 1;
|
||||
dir->i_sb->s_dirt = 1;
|
||||
btrfs_update_inode_block_group(trans, dir);
|
||||
btrfs_update_inode(trans, root, inode);
|
||||
|
||||
btrfs_end_transaction(trans, root);
|
||||
mutex_unlock(&root->fs_info->fs_mutex);
|
||||
|
||||
if (drop_inode) {
|
||||
inode_dec_link_count(inode);
|
||||
iput(inode);
|
||||
}
|
||||
btrfs_btree_balance_dirty(root);
|
||||
return err;
|
||||
}
|
||||
|
||||
static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
|
||||
struct btrfs_root *root,
|
||||
u64 objectid, u64 dirid)
|
||||
|
@ -2577,33 +2615,25 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
|
|||
}
|
||||
|
||||
|
||||
ret = btrfs_add_link(trans, new_dentry, old_inode);
|
||||
if (ret == -EEXIST && new_inode)
|
||||
ret = 0;
|
||||
else if (ret)
|
||||
goto out_fail;
|
||||
|
||||
ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
|
||||
if (ret)
|
||||
goto out_fail;
|
||||
|
||||
if (new_inode) {
|
||||
new_inode->i_ctime = CURRENT_TIME;
|
||||
di = btrfs_lookup_dir_index_item(trans, root, path,
|
||||
new_dir->i_ino,
|
||||
new_inode->i_ino,
|
||||
new_dentry->d_name.name,
|
||||
new_dentry->d_name.len, -1);
|
||||
if (di && !IS_ERR(di)) {
|
||||
btrfs_del_item(trans, root, path);
|
||||
btrfs_release_path(root, path);
|
||||
}
|
||||
ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
|
||||
if (ret)
|
||||
goto out_fail;
|
||||
if (S_ISDIR(new_inode->i_mode))
|
||||
clear_nlink(new_inode);
|
||||
else
|
||||
drop_nlink(new_inode);
|
||||
btrfs_update_inode(trans, root, new_inode);
|
||||
}
|
||||
ret = btrfs_add_link(trans, new_dentry, old_inode);
|
||||
if (ret)
|
||||
goto out_fail;
|
||||
|
||||
out_fail:
|
||||
btrfs_free_path(path);
|
||||
btrfs_end_transaction(trans, root);
|
||||
|
@ -2611,6 +2641,94 @@ out_fail:
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
|
||||
const char *symname)
|
||||
{
|
||||
struct btrfs_trans_handle *trans;
|
||||
struct btrfs_root *root = BTRFS_I(dir)->root;
|
||||
struct btrfs_path *path;
|
||||
struct btrfs_key key;
|
||||
struct inode *inode;
|
||||
int err;
|
||||
int drop_inode = 0;
|
||||
u64 objectid;
|
||||
int name_len;
|
||||
int datasize;
|
||||
char *ptr;
|
||||
struct btrfs_file_extent_item *ei;
|
||||
|
||||
name_len = strlen(symname) + 1;
|
||||
if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
|
||||
return -ENAMETOOLONG;
|
||||
mutex_lock(&root->fs_info->fs_mutex);
|
||||
trans = btrfs_start_transaction(root, 1);
|
||||
btrfs_set_trans_block_group(trans, dir);
|
||||
|
||||
err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
|
||||
if (err) {
|
||||
err = -ENOSPC;
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
inode = btrfs_new_inode(trans, root, objectid,
|
||||
BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
|
||||
err = PTR_ERR(inode);
|
||||
if (IS_ERR(inode))
|
||||
goto out_unlock;
|
||||
|
||||
btrfs_set_trans_block_group(trans, inode);
|
||||
err = btrfs_add_nondir(trans, dentry, inode);
|
||||
if (err)
|
||||
drop_inode = 1;
|
||||
else {
|
||||
inode->i_mapping->a_ops = &btrfs_aops;
|
||||
inode->i_fop = &btrfs_file_operations;
|
||||
inode->i_op = &btrfs_file_inode_operations;
|
||||
}
|
||||
dir->i_sb->s_dirt = 1;
|
||||
btrfs_update_inode_block_group(trans, inode);
|
||||
btrfs_update_inode_block_group(trans, dir);
|
||||
if (drop_inode)
|
||||
goto out_unlock;
|
||||
|
||||
path = btrfs_alloc_path();
|
||||
BUG_ON(!path);
|
||||
key.objectid = inode->i_ino;
|
||||
key.offset = 0;
|
||||
key.flags = 0;
|
||||
btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
|
||||
datasize = btrfs_file_extent_calc_inline_size(name_len);
|
||||
err = btrfs_insert_empty_item(trans, root, path, &key,
|
||||
datasize);
|
||||
BUG_ON(err);
|
||||
ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
|
||||
path->slots[0], struct btrfs_file_extent_item);
|
||||
btrfs_set_file_extent_generation(ei, trans->transid);
|
||||
btrfs_set_file_extent_type(ei,
|
||||
BTRFS_FILE_EXTENT_INLINE);
|
||||
ptr = btrfs_file_extent_inline_start(ei);
|
||||
btrfs_memcpy(root, path->nodes[0]->b_data,
|
||||
ptr, symname, name_len);
|
||||
mark_buffer_dirty(path->nodes[0]);
|
||||
btrfs_free_path(path);
|
||||
inode->i_op = &btrfs_symlink_inode_operations;
|
||||
inode->i_mapping->a_ops = &btrfs_symlink_aops;
|
||||
inode->i_size = name_len - 1;
|
||||
btrfs_update_inode(trans, root, inode);
|
||||
err = 0;
|
||||
|
||||
out_unlock:
|
||||
btrfs_end_transaction(trans, root);
|
||||
mutex_unlock(&root->fs_info->fs_mutex);
|
||||
|
||||
if (drop_inode) {
|
||||
inode_dec_link_count(inode);
|
||||
iput(inode);
|
||||
}
|
||||
btrfs_btree_balance_dirty(root);
|
||||
return err;
|
||||
}
|
||||
|
||||
static struct file_system_type btrfs_fs_type = {
|
||||
.owner = THIS_MODULE,
|
||||
.name = "btrfs",
|
||||
|
@ -2636,9 +2754,11 @@ static struct inode_operations btrfs_dir_inode_operations = {
|
|||
.lookup = btrfs_lookup,
|
||||
.create = btrfs_create,
|
||||
.unlink = btrfs_unlink,
|
||||
.link = btrfs_link,
|
||||
.mkdir = btrfs_mkdir,
|
||||
.rmdir = btrfs_rmdir,
|
||||
.rename = btrfs_rename,
|
||||
.symlink = btrfs_symlink,
|
||||
};
|
||||
|
||||
static struct inode_operations btrfs_dir_ro_inode_operations = {
|
||||
|
@ -2660,6 +2780,11 @@ static struct address_space_operations btrfs_aops = {
|
|||
.commit_write = btrfs_commit_write,
|
||||
};
|
||||
|
||||
static struct address_space_operations btrfs_symlink_aops = {
|
||||
.readpage = btrfs_readpage,
|
||||
.writepage = btrfs_writepage,
|
||||
};
|
||||
|
||||
static struct inode_operations btrfs_file_inode_operations = {
|
||||
.truncate = btrfs_truncate,
|
||||
.getattr = btrfs_getattr,
|
||||
|
@ -2676,6 +2801,12 @@ static struct file_operations btrfs_file_operations = {
|
|||
.fsync = btrfs_sync_file,
|
||||
};
|
||||
|
||||
static struct inode_operations btrfs_symlink_inode_operations = {
|
||||
.readlink = generic_readlink,
|
||||
.follow_link = page_follow_link_light,
|
||||
.put_link = page_put_link,
|
||||
};
|
||||
|
||||
static int __init init_btrfs_fs(void)
|
||||
{
|
||||
int err;
|
||||
|
|
Загрузка…
Ссылка в новой задаче