static noinline int create_subvol(struct btrfs_root *root,
struct dentry *dentry,
- char *name, int namelen)
+ char *name, int namelen,
+ u64 *async_transid)
{
struct btrfs_trans_handle *trans;
struct btrfs_key key;
d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
fail:
- err = btrfs_commit_transaction(trans, root);
+ if (async_transid) {
+ *async_transid = trans->transid;
+ err = btrfs_commit_transaction_async(trans, root, 1);
+ } else {
+ err = btrfs_commit_transaction(trans, root);
+ }
if (err && !ret)
ret = err;
return ret;
}
-static int create_snapshot(struct btrfs_root *root, struct dentry *dentry)
+static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
+ char *name, int namelen, u64 *async_transid)
{
struct inode *inode;
struct btrfs_pending_snapshot *pending_snapshot;
list_add(&pending_snapshot->list,
&trans->transaction->pending_snapshots);
- ret = btrfs_commit_transaction(trans, root->fs_info->extent_root);
+ if (async_transid) {
+ *async_transid = trans->transid;
+ ret = btrfs_commit_transaction_async(trans,
+ root->fs_info->extent_root, 1);
+ } else {
+ ret = btrfs_commit_transaction(trans,
+ root->fs_info->extent_root);
+ }
BUG_ON(ret);
ret = pending_snapshot->error;
return ret;
}
+/* copy of check_sticky in fs/namei.c()
+* It's inline, so penalty for filesystems that don't use sticky bit is
+* minimal.
+*/
+static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
+{
+ uid_t fsuid = current_fsuid();
+
+ if (!(dir->i_mode & S_ISVTX))
+ return 0;
+ if (inode->i_uid == fsuid)
+ return 0;
+ if (dir->i_uid == fsuid)
+ return 0;
+ return !capable(CAP_FOWNER);
+}
+
+/* copy of may_delete in fs/namei.c()
+ * Check whether we can remove a link victim from directory dir, check
+ * whether the type of victim is right.
+ * 1. We can't do it if dir is read-only (done in permission())
+ * 2. We should have write and exec permissions on dir
+ * 3. We can't remove anything from append-only dir
+ * 4. We can't do anything with immutable dir (done in permission())
+ * 5. If the sticky bit on dir is set we should either
+ * a. be owner of dir, or
+ * b. be owner of victim, or
+ * c. have CAP_FOWNER capability
+ * 6. If the victim is append-only or immutable we can't do antyhing with
+ * links pointing to it.
+ * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
+ * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
+ * 9. We can't remove a root or mountpoint.
+ * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
+ * nfs_async_unlink().
+ */
+
+static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
+{
+ int error;
+
+ if (!victim->d_inode)
+ return -ENOENT;
+
+ BUG_ON(victim->d_parent->d_inode != dir);
+ audit_inode_child(victim, dir);
+
+ error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ if (error)
+ return error;
+ if (IS_APPEND(dir))
+ return -EPERM;
+ if (btrfs_check_sticky(dir, victim->d_inode)||
+ IS_APPEND(victim->d_inode)||
+ IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
+ return -EPERM;
+ if (isdir) {
+ if (!S_ISDIR(victim->d_inode->i_mode))
+ return -ENOTDIR;
+ if (IS_ROOT(victim))
+ return -EBUSY;
+ } else if (S_ISDIR(victim->d_inode->i_mode))
+ return -EISDIR;
+ if (IS_DEADDIR(dir))
+ return -ENOENT;
+ if (victim->d_flags & DCACHE_NFSFS_RENAMED)
+ return -EBUSY;
+ return 0;
+}
+
/* copy of may_create in fs/namei.c() */
static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
{
*/
static noinline int btrfs_mksubvol(struct path *parent,
char *name, int namelen,
- struct btrfs_root *snap_src)
+ struct btrfs_root *snap_src,
+ u64 *async_transid)
{
struct inode *dir = parent->dentry->d_inode;
struct dentry *dentry;
goto out_up_read;
if (snap_src) {
- error = create_snapshot(snap_src, dentry);
+ error = create_snapshot(snap_src, dentry,
+ name, namelen, async_transid);
} else {
error = create_subvol(BTRFS_I(dir)->root, dentry,
- name, namelen);
+ name, namelen, async_transid);
}
if (!error)
fsnotify_mkdir(dir, dentry);
return ret;
}
-static noinline int btrfs_ioctl_snap_create(struct file *file,
- void __user *arg, int subvol)
+static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
+ char *name,
+ unsigned long fd,
+ int subvol,
+ u64 *transid)
{
struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
- struct btrfs_ioctl_vol_args *vol_args;
struct file *src_file;
int namelen;
int ret = 0;
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
- vol_args = memdup_user(arg, sizeof(*vol_args));
- if (IS_ERR(vol_args))
- return PTR_ERR(vol_args);
-
- vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
- namelen = strlen(vol_args->name);
- if (strchr(vol_args->name, '/')) {
+ namelen = strlen(name);
+ if (strchr(name, '/')) {
ret = -EINVAL;
goto out;
}
if (subvol) {
- ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
- NULL);
+ ret = btrfs_mksubvol(&file->f_path, name, namelen,
+ NULL, transid);
} else {
struct inode *src_inode;
- src_file = fget(vol_args->fd);
+ src_file = fget(fd);
if (!src_file) {
ret = -EINVAL;
goto out;
fput(src_file);
goto out;
}
- ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
- BTRFS_I(src_inode)->root);
+ ret = btrfs_mksubvol(&file->f_path, name, namelen,
+ BTRFS_I(src_inode)->root,
+ transid);
fput(src_file);
}
out:
+ return ret;
+}
+
+static noinline int btrfs_ioctl_snap_create(struct file *file,
+ void __user *arg, int subvol,
+ int async)
+{
+ struct btrfs_ioctl_vol_args *vol_args = NULL;
+ struct btrfs_ioctl_async_vol_args *async_vol_args = NULL;
+ char *name;
+ u64 fd;
+ u64 transid = 0;
+ int ret;
+
+ if (async) {
+ async_vol_args = memdup_user(arg, sizeof(*async_vol_args));
+ if (IS_ERR(async_vol_args))
+ return PTR_ERR(async_vol_args);
+
+ name = async_vol_args->name;
+ fd = async_vol_args->fd;
+ async_vol_args->name[BTRFS_SNAPSHOT_NAME_MAX] = '\0';
+ } else {
+ vol_args = memdup_user(arg, sizeof(*vol_args));
+ if (IS_ERR(vol_args))
+ return PTR_ERR(vol_args);
+ name = vol_args->name;
+ fd = vol_args->fd;
+ vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+ }
+
+ ret = btrfs_ioctl_snap_create_transid(file, name, fd,
+ subvol, &transid);
+
+ if (!ret && async) {
+ if (copy_to_user(arg +
+ offsetof(struct btrfs_ioctl_async_vol_args,
+ transid), &transid, sizeof(transid)))
+ return -EFAULT;
+ }
+
kfree(vol_args);
+ kfree(async_vol_args);
+
return ret;
}
int ret;
int err = 0;
- if (!capable(CAP_SYS_ADMIN))
- return -EPERM;
-
vol_args = memdup_user(arg, sizeof(*vol_args));
if (IS_ERR(vol_args))
return PTR_ERR(vol_args);
}
inode = dentry->d_inode;
+ dest = BTRFS_I(inode)->root;
+ if (!capable(CAP_SYS_ADMIN)){
+ /*
+ * Regular user. Only allow this with a special mount
+ * option, when the user has write+exec access to the
+ * subvol root, and when rmdir(2) would have been
+ * allowed.
+ *
+ * Note that this is _not_ check that the subvol is
+ * empty or doesn't contain data that we wouldn't
+ * otherwise be able to delete.
+ *
+ * Users who want to delete empty subvols should try
+ * rmdir(2).
+ */
+ err = -EPERM;
+ if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
+ goto out_dput;
+
+ /*
+ * Do not allow deletion if the parent dir is the same
+ * as the dir to be deleted. That means the ioctl
+ * must be called on the dentry referencing the root
+ * of the subvol, not a random directory contained
+ * within it.
+ */
+ err = -EINVAL;
+ if (root == dest)
+ goto out_dput;
+
+ err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
+ if (err)
+ goto out_dput;
+
+ /* check if subvolume may be deleted by a non-root user */
+ err = btrfs_may_delete(dir, dentry, 1);
+ if (err)
+ goto out_dput;
+ }
+
if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
err = -EINVAL;
goto out_dput;
}
- dest = BTRFS_I(inode)->root;
-
mutex_lock(&inode->i_mutex);
err = d_invalidate(dentry);
if (err)
BUG_ON(ret);
}
- ret = btrfs_commit_transaction(trans, root);
+ ret = btrfs_end_transaction(trans, root);
BUG_ON(ret);
inode->i_flags |= S_DEAD;
out_up_write:
case FS_IOC_GETVERSION:
return btrfs_ioctl_getversion(file, argp);
case BTRFS_IOC_SNAP_CREATE:
- return btrfs_ioctl_snap_create(file, argp, 0);
+ return btrfs_ioctl_snap_create(file, argp, 0, 0);
+ case BTRFS_IOC_SNAP_CREATE_ASYNC:
+ return btrfs_ioctl_snap_create(file, argp, 0, 1);
case BTRFS_IOC_SUBVOL_CREATE:
- return btrfs_ioctl_snap_create(file, argp, 1);
+ return btrfs_ioctl_snap_create(file, argp, 1, 0);
case BTRFS_IOC_SNAP_DESTROY:
return btrfs_ioctl_snap_destroy(file, argp);
case BTRFS_IOC_DEFAULT_SUBVOL:
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff