* [PATCH v3 0/3] Allow rmdir(2) to delete a subvolume
@ 2018-03-30 6:15 Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 1/3] btrfs: move may_destroy_subvol() from ioctl.c to inode.c Misono Tomohiro
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Misono Tomohiro @ 2018-03-30 6:15 UTC (permalink / raw)
To: linux-btrfs
changelog:
v2 -> v3 ... use if-else block instead of two if blocks and
add Tested-by tag in 2nd patch
v1 -> v2 ... split the patch to hopefully make review easier
Note: I will send a xfstest if this series is merged.
1st patch is a preparation work just moving the declaration of
may_destroy_subvol().
2nd patch is the main part. New function btrfs_delete_subvolume() is
introduced and used in btrfs_rmdir() when a direcoty is an empty
subvolume. The function is almost the copy of second half of
btrfs_ioctl_snap_destroy().
The code path for "sub delete" is not changed yet.
3rd patch is a cleanup of btrfs_ioctl_snap_destroy() and uses
brrfs_delete_subvolume() for "sub delete" too.
Tomohiro Misono (3):
btrfs: move may_destroy_subvol() from ioctl.c to inode.c
btrfs: Allow rmdir(2) to delete a subvolume
btrfs: cleanup btrfs_ioctl_snap_destroy() by using
btrfs_delete_subvolume()
fs/btrfs/ctree.h | 5 +-
fs/btrfs/inode.c | 197 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
fs/btrfs/ioctl.c | 185 +--------------------------------------------------
3 files changed, 198 insertions(+), 189 deletions(-)
--
2.14.3
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v3 1/3] btrfs: move may_destroy_subvol() from ioctl.c to inode.c
2018-03-30 6:15 [PATCH v3 0/3] Allow rmdir(2) to delete a subvolume Misono Tomohiro
@ 2018-03-30 6:16 ` Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume Misono Tomohiro
2018-03-30 6:17 ` [PATCH v3 3/3] btrfs: cleanup btrfs_ioctl_snap_destroy() by using btrfs_delete_subvolume() Misono Tomohiro
2 siblings, 0 replies; 6+ messages in thread
From: Misono Tomohiro @ 2018-03-30 6:16 UTC (permalink / raw)
To: linux-btrfs
This is a preparation work to allow rmdir(2) to delete a subvolume.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/inode.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/ioctl.c | 54 ------------------------------------------------------
3 files changed, 55 insertions(+), 54 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index da308774b8a4..2dbead106aab 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3166,6 +3166,7 @@ int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct inode *dir, u64 objectid,
const char *name, int name_len);
+noinline int may_destroy_subvol(struct btrfs_root *root);
int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
int front);
int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f53470112670..db66fa4fede6 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4333,6 +4333,60 @@ int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
return ret;
}
+/*
+ * helper to check if the subvolume references other subvolumes
+ */
+noinline int may_destroy_subvol(struct btrfs_root *root)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_path *path;
+ struct btrfs_dir_item *di;
+ struct btrfs_key key;
+ u64 dir_id;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+
+ /* Make sure this root isn't set as the default subvol */
+ dir_id = btrfs_super_root_dir(fs_info->super_copy);
+ di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
+ dir_id, "default", 7, 0);
+ if (di && !IS_ERR(di)) {
+ btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
+ if (key.objectid == root->root_key.objectid) {
+ ret = -EPERM;
+ btrfs_err(fs_info,
+ "deleting default subvolume %llu is not allowed",
+ key.objectid);
+ goto out;
+ }
+ btrfs_release_path(path);
+ }
+
+ key.objectid = root->root_key.objectid;
+ key.type = BTRFS_ROOT_REF_KEY;
+ key.offset = (u64)-1;
+
+ ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
+ if (ret < 0)
+ goto out;
+ BUG_ON(ret == 0);
+
+ ret = 0;
+ if (path->slots[0] > 0) {
+ path->slots[0]--;
+ btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
+ if (key.objectid == root->root_key.objectid &&
+ key.type == BTRFS_ROOT_REF_KEY)
+ ret = -ENOTEMPTY;
+ }
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 111ee282b777..11af9eb449ef 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1843,60 +1843,6 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
return ret;
}
-/*
- * helper to check if the subvolume references other subvolumes
- */
-static noinline int may_destroy_subvol(struct btrfs_root *root)
-{
- struct btrfs_fs_info *fs_info = root->fs_info;
- struct btrfs_path *path;
- struct btrfs_dir_item *di;
- struct btrfs_key key;
- u64 dir_id;
- int ret;
-
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
-
- /* Make sure this root isn't set as the default subvol */
- dir_id = btrfs_super_root_dir(fs_info->super_copy);
- di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
- dir_id, "default", 7, 0);
- if (di && !IS_ERR(di)) {
- btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
- if (key.objectid == root->root_key.objectid) {
- ret = -EPERM;
- btrfs_err(fs_info,
- "deleting default subvolume %llu is not allowed",
- key.objectid);
- goto out;
- }
- btrfs_release_path(path);
- }
-
- key.objectid = root->root_key.objectid;
- key.type = BTRFS_ROOT_REF_KEY;
- key.offset = (u64)-1;
-
- ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
- if (ret < 0)
- goto out;
- BUG_ON(ret == 0);
-
- ret = 0;
- if (path->slots[0] > 0) {
- path->slots[0]--;
- btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
- if (key.objectid == root->root_key.objectid &&
- key.type == BTRFS_ROOT_REF_KEY)
- ret = -ENOTEMPTY;
- }
-out:
- btrfs_free_path(path);
- return ret;
-}
-
static noinline int key_in_sk(struct btrfs_key *key,
struct btrfs_ioctl_search_key *sk)
{
--
2.14.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume
2018-03-30 6:15 [PATCH v3 0/3] Allow rmdir(2) to delete a subvolume Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 1/3] btrfs: move may_destroy_subvol() from ioctl.c to inode.c Misono Tomohiro
@ 2018-03-30 6:16 ` Misono Tomohiro
2018-04-06 14:46 ` David Sterba
2018-03-30 6:17 ` [PATCH v3 3/3] btrfs: cleanup btrfs_ioctl_snap_destroy() by using btrfs_delete_subvolume() Misono Tomohiro
2 siblings, 1 reply; 6+ messages in thread
From: Misono Tomohiro @ 2018-03-30 6:16 UTC (permalink / raw)
To: linux-btrfs
This patch changes the behavior of rmdir(2) to allow it to delete
an empty subvolume by default, unless it is not a default subvolume
and send is not in progress.
New function btrfs_delete_subvolume() is almost equal to the second half
of btrfs_ioctl_snap_destroy(). This function requires inode_lock for both
@dir and inode of @dentry. For rmdir(2) it is already acquired in vfs
layer before calling btrfs_rmdir().
Note that while a non-privileged user cannot delete a read-only subvolume
by "btrfs subvolume delete" when user_subvol_rm_allowd mount option is
enabled, rmdir(2) can delete an empty read-only subvolume.
Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
---
fs/btrfs/inode.c | 141 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 140 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index db66fa4fede6..84dbb9cafd6b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4387,6 +4387,145 @@ noinline int may_destroy_subvol(struct btrfs_root *root)
return ret;
}
+static int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct inode *inode = d_inode(dentry);
+ struct btrfs_root *dest = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_block_rsv block_rsv;
+ u64 root_flags;
+ u64 qgroup_reserved;
+ int ret;
+ int err;
+
+ /*
+ * Don't allow to delete a subvolume with send in progress. This is
+ * inside the i_mutex so the error handling that has to drop the bit
+ * again is not run concurrently.
+ */
+ spin_lock(&dest->root_item_lock);
+ root_flags = btrfs_root_flags(&dest->root_item);
+ if (dest->send_in_progress == 0) {
+ btrfs_set_root_flags(&dest->root_item,
+ root_flags | BTRFS_ROOT_SUBVOL_DEAD);
+ spin_unlock(&dest->root_item_lock);
+ } else {
+ spin_unlock(&dest->root_item_lock);
+ btrfs_warn(fs_info,
+ "Attempt to delete subvolume %llu during send",
+ dest->root_key.objectid);
+ err = -EPERM;
+ return err;
+ }
+
+ down_write(&fs_info->subvol_sem);
+
+ err = may_destroy_subvol(dest);
+ if (err)
+ goto out_up_write;
+
+ btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
+ /*
+ * One for dir inode, two for dir entries, two for root
+ * ref/backref.
+ */
+ err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
+ 5, &qgroup_reserved, true);
+ if (err)
+ goto out_up_write;
+
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans)) {
+ err = PTR_ERR(trans);
+ goto out_release;
+ }
+ trans->block_rsv = &block_rsv;
+ trans->bytes_reserved = block_rsv.size;
+
+ btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
+
+ ret = btrfs_unlink_subvol(trans, root, dir,
+ dest->root_key.objectid,
+ dentry->d_name.name,
+ dentry->d_name.len);
+ if (ret) {
+ err = ret;
+ btrfs_abort_transaction(trans, ret);
+ goto out_end_trans;
+ }
+
+ btrfs_record_root_in_trans(trans, dest);
+
+ memset(&dest->root_item.drop_progress, 0,
+ sizeof(dest->root_item.drop_progress));
+ dest->root_item.drop_level = 0;
+ btrfs_set_root_refs(&dest->root_item, 0);
+
+ if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
+ ret = btrfs_insert_orphan_item(trans,
+ fs_info->tree_root,
+ dest->root_key.objectid);
+ if (ret) {
+ btrfs_abort_transaction(trans, ret);
+ err = ret;
+ goto out_end_trans;
+ }
+ }
+
+ ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
+ BTRFS_UUID_KEY_SUBVOL,
+ dest->root_key.objectid);
+ if (ret && ret != -ENOENT) {
+ btrfs_abort_transaction(trans, ret);
+ err = ret;
+ goto out_end_trans;
+ }
+ if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
+ ret = btrfs_uuid_tree_rem(trans, fs_info,
+ dest->root_item.received_uuid,
+ BTRFS_UUID_KEY_RECEIVED_SUBVOL,
+ dest->root_key.objectid);
+ if (ret && ret != -ENOENT) {
+ btrfs_abort_transaction(trans, ret);
+ err = ret;
+ goto out_end_trans;
+ }
+ }
+
+out_end_trans:
+ trans->block_rsv = NULL;
+ trans->bytes_reserved = 0;
+ ret = btrfs_end_transaction(trans);
+ if (ret && !err)
+ err = ret;
+ inode->i_flags |= S_DEAD;
+out_release:
+ btrfs_subvolume_release_metadata(fs_info, &block_rsv);
+out_up_write:
+ up_write(&fs_info->subvol_sem);
+ if (err) {
+ spin_lock(&dest->root_item_lock);
+ root_flags = btrfs_root_flags(&dest->root_item);
+ btrfs_set_root_flags(&dest->root_item,
+ root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
+ spin_unlock(&dest->root_item_lock);
+ } else {
+ d_invalidate(dentry);
+ btrfs_invalidate_inodes(dest);
+ ASSERT(dest->send_in_progress == 0);
+
+ /* the last ref */
+ if (dest->ino_cache_inode) {
+ iput(dest->ino_cache_inode);
+ dest->ino_cache_inode = NULL;
+ }
+ }
+
+ return err;
+}
+
static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
@@ -4398,7 +4537,7 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
return -ENOTEMPTY;
if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
- return -EPERM;
+ return btrfs_delete_subvolume(dir, dentry);
trans = __unlink_start_trans(dir);
if (IS_ERR(trans))
--
2.14.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v3 3/3] btrfs: cleanup btrfs_ioctl_snap_destroy() by using btrfs_delete_subvolume()
2018-03-30 6:15 [PATCH v3 0/3] Allow rmdir(2) to delete a subvolume Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 1/3] btrfs: move may_destroy_subvol() from ioctl.c to inode.c Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume Misono Tomohiro
@ 2018-03-30 6:17 ` Misono Tomohiro
2 siblings, 0 replies; 6+ messages in thread
From: Misono Tomohiro @ 2018-03-30 6:17 UTC (permalink / raw)
To: linux-btrfs
Use btrfs_delete_subvolume() in btrfs_ioctl_snap_destroy() too to
cleanup the code. Call of d_delete() is still required since
btrfs_delete_subvolume() does not call it (for rmdir(2), vfs layer later
calls it).
As a result, btrfs_unlink_subvol() and may_destroy_subvol()
become static functions. No functional change happens.
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
---
fs/btrfs/ctree.h | 6 +--
fs/btrfs/inode.c | 6 +--
fs/btrfs/ioctl.c | 131 +------------------------------------------------------
3 files changed, 6 insertions(+), 137 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2dbead106aab..6f23f0694ac3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3162,11 +3162,7 @@ int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
int btrfs_add_link(struct btrfs_trans_handle *trans,
struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
const char *name, int name_len, int add_backref, u64 index);
-int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct inode *dir, u64 objectid,
- const char *name, int name_len);
-noinline int may_destroy_subvol(struct btrfs_root *root);
+int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry);
int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
int front);
int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 84dbb9cafd6b..afc631f28088 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4252,7 +4252,7 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
return ret;
}
-int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
+static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct inode *dir, u64 objectid,
const char *name, int name_len)
@@ -4336,7 +4336,7 @@ int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
/*
* helper to check if the subvolume references other subvolumes
*/
-noinline int may_destroy_subvol(struct btrfs_root *root)
+static noinline int may_destroy_subvol(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_path *path;
@@ -4387,7 +4387,7 @@ noinline int may_destroy_subvol(struct btrfs_root *root)
return ret;
}
-static int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
+int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
{
struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
struct btrfs_root *root = BTRFS_I(dir)->root;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 11af9eb449ef..7559a1a82e6d 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2266,12 +2266,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_root *dest = NULL;
struct btrfs_ioctl_vol_args *vol_args;
- struct btrfs_trans_handle *trans;
- struct btrfs_block_rsv block_rsv;
- u64 root_flags;
- u64 qgroup_reserved;
int namelen;
- int ret;
int err = 0;
if (!S_ISDIR(dir->i_mode))
@@ -2355,133 +2350,11 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
}
inode_lock(inode);
-
- /*
- * Don't allow to delete a subvolume with send in progress. This is
- * inside the i_mutex so the error handling that has to drop the bit
- * again is not run concurrently.
- */
- spin_lock(&dest->root_item_lock);
- root_flags = btrfs_root_flags(&dest->root_item);
- if (dest->send_in_progress == 0) {
- btrfs_set_root_flags(&dest->root_item,
- root_flags | BTRFS_ROOT_SUBVOL_DEAD);
- spin_unlock(&dest->root_item_lock);
- } else {
- spin_unlock(&dest->root_item_lock);
- btrfs_warn(fs_info,
- "Attempt to delete subvolume %llu during send",
- dest->root_key.objectid);
- err = -EPERM;
- goto out_unlock_inode;
- }
-
- down_write(&fs_info->subvol_sem);
-
- err = may_destroy_subvol(dest);
- if (err)
- goto out_up_write;
-
- btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
- /*
- * One for dir inode, two for dir entries, two for root
- * ref/backref.
- */
- err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
- 5, &qgroup_reserved, true);
- if (err)
- goto out_up_write;
-
- trans = btrfs_start_transaction(root, 0);
- if (IS_ERR(trans)) {
- err = PTR_ERR(trans);
- goto out_release;
- }
- trans->block_rsv = &block_rsv;
- trans->bytes_reserved = block_rsv.size;
-
- btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
-
- ret = btrfs_unlink_subvol(trans, root, dir,
- dest->root_key.objectid,
- dentry->d_name.name,
- dentry->d_name.len);
- if (ret) {
- err = ret;
- btrfs_abort_transaction(trans, ret);
- goto out_end_trans;
- }
-
- btrfs_record_root_in_trans(trans, dest);
-
- memset(&dest->root_item.drop_progress, 0,
- sizeof(dest->root_item.drop_progress));
- dest->root_item.drop_level = 0;
- btrfs_set_root_refs(&dest->root_item, 0);
-
- if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
- ret = btrfs_insert_orphan_item(trans,
- fs_info->tree_root,
- dest->root_key.objectid);
- if (ret) {
- btrfs_abort_transaction(trans, ret);
- err = ret;
- goto out_end_trans;
- }
- }
-
- ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
- BTRFS_UUID_KEY_SUBVOL,
- dest->root_key.objectid);
- if (ret && ret != -ENOENT) {
- btrfs_abort_transaction(trans, ret);
- err = ret;
- goto out_end_trans;
- }
- if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
- ret = btrfs_uuid_tree_rem(trans, fs_info,
- dest->root_item.received_uuid,
- BTRFS_UUID_KEY_RECEIVED_SUBVOL,
- dest->root_key.objectid);
- if (ret && ret != -ENOENT) {
- btrfs_abort_transaction(trans, ret);
- err = ret;
- goto out_end_trans;
- }
- }
-
-out_end_trans:
- trans->block_rsv = NULL;
- trans->bytes_reserved = 0;
- ret = btrfs_end_transaction(trans);
- if (ret && !err)
- err = ret;
- inode->i_flags |= S_DEAD;
-out_release:
- btrfs_subvolume_release_metadata(fs_info, &block_rsv);
-out_up_write:
- up_write(&fs_info->subvol_sem);
- if (err) {
- spin_lock(&dest->root_item_lock);
- root_flags = btrfs_root_flags(&dest->root_item);
- btrfs_set_root_flags(&dest->root_item,
- root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
- spin_unlock(&dest->root_item_lock);
- }
-out_unlock_inode:
+ err = btrfs_delete_subvolume(dir, dentry);
inode_unlock(inode);
- if (!err) {
- d_invalidate(dentry);
- btrfs_invalidate_inodes(dest);
+ if (!err)
d_delete(dentry);
- ASSERT(dest->send_in_progress == 0);
- /* the last ref */
- if (dest->ino_cache_inode) {
- iput(dest->ino_cache_inode);
- dest->ino_cache_inode = NULL;
- }
- }
out_dput:
dput(dentry);
out_unlock_dir:
--
2.14.3
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume
2018-03-30 6:16 ` [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume Misono Tomohiro
@ 2018-04-06 14:46 ` David Sterba
2018-04-11 5:16 ` Misono Tomohiro
0 siblings, 1 reply; 6+ messages in thread
From: David Sterba @ 2018-04-06 14:46 UTC (permalink / raw)
To: Misono Tomohiro; +Cc: linux-btrfs
On Fri, Mar 30, 2018 at 03:16:47PM +0900, Misono Tomohiro wrote:
> This patch changes the behavior of rmdir(2) to allow it to delete
> an empty subvolume by default, unless it is not a default subvolume
> and send is not in progress.
>
> New function btrfs_delete_subvolume() is almost equal to the second half
> of btrfs_ioctl_snap_destroy(). This function requires inode_lock for both
> @dir and inode of @dentry. For rmdir(2) it is already acquired in vfs
> layer before calling btrfs_rmdir().
>
> Note that while a non-privileged user cannot delete a read-only subvolume
> by "btrfs subvolume delete" when user_subvol_rm_allowd mount option is
> enabled, rmdir(2) can delete an empty read-only subvolume.
>
> Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
> Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
> ---
> fs/btrfs/inode.c | 141 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 140 insertions(+), 1 deletion(-)
>
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index db66fa4fede6..84dbb9cafd6b 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -4387,6 +4387,145 @@ noinline int may_destroy_subvol(struct btrfs_root *root)
> return ret;
> }
>
> +static int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
> +{
> + struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
> + struct btrfs_root *root = BTRFS_I(dir)->root;
> + struct inode *inode = d_inode(dentry);
> + struct btrfs_root *dest = BTRFS_I(inode)->root;
> + struct btrfs_trans_handle *trans;
> + struct btrfs_block_rsv block_rsv;
> + u64 root_flags;
> + u64 qgroup_reserved;
> + int ret;
> + int err;
> +
> + /*
> + * Don't allow to delete a subvolume with send in progress. This is
> + * inside the i_mutex so the error handling that has to drop the bit
> + * again is not run concurrently.
> + */
> + spin_lock(&dest->root_item_lock);
> + root_flags = btrfs_root_flags(&dest->root_item);
> + if (dest->send_in_progress == 0) {
> + btrfs_set_root_flags(&dest->root_item,
> + root_flags | BTRFS_ROOT_SUBVOL_DEAD);
> + spin_unlock(&dest->root_item_lock);
> + } else {
> + spin_unlock(&dest->root_item_lock);
> + btrfs_warn(fs_info,
> + "Attempt to delete subvolume %llu during send",
> + dest->root_key.objectid);
> + err = -EPERM;
> + return err;
> + }
> +
> + down_write(&fs_info->subvol_sem);
> +
> + err = may_destroy_subvol(dest);
> + if (err)
> + goto out_up_write;
> +
> + btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
> + /*
> + * One for dir inode, two for dir entries, two for root
> + * ref/backref.
> + */
> + err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
> + 5, &qgroup_reserved, true);
> + if (err)
> + goto out_up_write;
> +
> + trans = btrfs_start_transaction(root, 0);
> + if (IS_ERR(trans)) {
> + err = PTR_ERR(trans);
> + goto out_release;
> + }
> + trans->block_rsv = &block_rsv;
> + trans->bytes_reserved = block_rsv.size;
> +
> + btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
> +
> + ret = btrfs_unlink_subvol(trans, root, dir,
> + dest->root_key.objectid,
> + dentry->d_name.name,
> + dentry->d_name.len);
> + if (ret) {
> + err = ret;
> + btrfs_abort_transaction(trans, ret);
> + goto out_end_trans;
> + }
> +
> + btrfs_record_root_in_trans(trans, dest);
> +
> + memset(&dest->root_item.drop_progress, 0,
> + sizeof(dest->root_item.drop_progress));
> + dest->root_item.drop_level = 0;
> + btrfs_set_root_refs(&dest->root_item, 0);
> +
> + if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
> + ret = btrfs_insert_orphan_item(trans,
> + fs_info->tree_root,
> + dest->root_key.objectid);
> + if (ret) {
> + btrfs_abort_transaction(trans, ret);
> + err = ret;
> + goto out_end_trans;
> + }
> + }
> +
> + ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
> + BTRFS_UUID_KEY_SUBVOL,
> + dest->root_key.objectid);
> + if (ret && ret != -ENOENT) {
> + btrfs_abort_transaction(trans, ret);
> + err = ret;
> + goto out_end_trans;
> + }
> + if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
> + ret = btrfs_uuid_tree_rem(trans, fs_info,
> + dest->root_item.received_uuid,
> + BTRFS_UUID_KEY_RECEIVED_SUBVOL,
> + dest->root_key.objectid);
> + if (ret && ret != -ENOENT) {
> + btrfs_abort_transaction(trans, ret);
> + err = ret;
> + goto out_end_trans;
> + }
> + }
> +
> +out_end_trans:
> + trans->block_rsv = NULL;
> + trans->bytes_reserved = 0;
> + ret = btrfs_end_transaction(trans);
> + if (ret && !err)
> + err = ret;
> + inode->i_flags |= S_DEAD;
> +out_release:
> + btrfs_subvolume_release_metadata(fs_info, &block_rsv);
> +out_up_write:
> + up_write(&fs_info->subvol_sem);
> + if (err) {
> + spin_lock(&dest->root_item_lock);
> + root_flags = btrfs_root_flags(&dest->root_item);
> + btrfs_set_root_flags(&dest->root_item,
> + root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
> + spin_unlock(&dest->root_item_lock);
> + } else {
> + d_invalidate(dentry);
> + btrfs_invalidate_inodes(dest);
> + ASSERT(dest->send_in_progress == 0);
> +
> + /* the last ref */
> + if (dest->ino_cache_inode) {
> + iput(dest->ino_cache_inode);
> + dest->ino_cache_inode = NULL;
> + }
> + }
> +
> + return err;
> +}
The change separation is still not right. Patch 2+3 should factor out
btrfs_delete_subvolume and do not any changes to rmdir behaviour. The
following patch will do what's in the hunk below, with enough reasonging
why it is so.
> +
> static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
> {
> struct inode *inode = d_inode(dentry);
> @@ -4398,7 +4537,7 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
> if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
> return -ENOTEMPTY;
> if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
> - return -EPERM;
> + return btrfs_delete_subvolume(dir, dentry);
>
> trans = __unlink_start_trans(dir);
> if (IS_ERR(trans))
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume
2018-04-06 14:46 ` David Sterba
@ 2018-04-11 5:16 ` Misono Tomohiro
0 siblings, 0 replies; 6+ messages in thread
From: Misono Tomohiro @ 2018-04-11 5:16 UTC (permalink / raw)
To: dsterba, linux-btrfs
On 2018/04/06 23:46, David Sterba wrote:
> On Fri, Mar 30, 2018 at 03:16:47PM +0900, Misono Tomohiro wrote:
>> This patch changes the behavior of rmdir(2) to allow it to delete
>> an empty subvolume by default, unless it is not a default subvolume
>> and send is not in progress.
>>
>> New function btrfs_delete_subvolume() is almost equal to the second half
>> of btrfs_ioctl_snap_destroy(). This function requires inode_lock for both
>> @dir and inode of @dentry. For rmdir(2) it is already acquired in vfs
>> layer before calling btrfs_rmdir().
>>
>> Note that while a non-privileged user cannot delete a read-only subvolume
>> by "btrfs subvolume delete" when user_subvol_rm_allowd mount option is
>> enabled, rmdir(2) can delete an empty read-only subvolume.
>>
>> Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
>> Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
>> ---
>> fs/btrfs/inode.c | 141 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
>> 1 file changed, 140 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
>> index db66fa4fede6..84dbb9cafd6b 100644
>> --- a/fs/btrfs/inode.c
>> +++ b/fs/btrfs/inode.c
>> @@ -4387,6 +4387,145 @@ noinline int may_destroy_subvol(struct btrfs_root *root)
>> return ret;
>> }
>>
>> +static int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
>> +{
>> + struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
>> + struct btrfs_root *root = BTRFS_I(dir)->root;
>> + struct inode *inode = d_inode(dentry);
>> + struct btrfs_root *dest = BTRFS_I(inode)->root;
>> + struct btrfs_trans_handle *trans;
>> + struct btrfs_block_rsv block_rsv;
>> + u64 root_flags;
>> + u64 qgroup_reserved;
>> + int ret;
>> + int err;
>> +
>> + /*
>> + * Don't allow to delete a subvolume with send in progress. This is
>> + * inside the i_mutex so the error handling that has to drop the bit
>> + * again is not run concurrently.
>> + */
>> + spin_lock(&dest->root_item_lock);
>> + root_flags = btrfs_root_flags(&dest->root_item);
>> + if (dest->send_in_progress == 0) {
>> + btrfs_set_root_flags(&dest->root_item,
>> + root_flags | BTRFS_ROOT_SUBVOL_DEAD);
>> + spin_unlock(&dest->root_item_lock);
>> + } else {
>> + spin_unlock(&dest->root_item_lock);
>> + btrfs_warn(fs_info,
>> + "Attempt to delete subvolume %llu during send",
>> + dest->root_key.objectid);
>> + err = -EPERM;
>> + return err;
>> + }
>> +
>> + down_write(&fs_info->subvol_sem);
>> +
>> + err = may_destroy_subvol(dest);
>> + if (err)
>> + goto out_up_write;
>> +
>> + btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
>> + /*
>> + * One for dir inode, two for dir entries, two for root
>> + * ref/backref.
>> + */
>> + err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
>> + 5, &qgroup_reserved, true);
>> + if (err)
>> + goto out_up_write;
>> +
>> + trans = btrfs_start_transaction(root, 0);
>> + if (IS_ERR(trans)) {
>> + err = PTR_ERR(trans);
>> + goto out_release;
>> + }
>> + trans->block_rsv = &block_rsv;
>> + trans->bytes_reserved = block_rsv.size;
>> +
>> + btrfs_record_snapshot_destroy(trans, BTRFS_I(dir));
>> +
>> + ret = btrfs_unlink_subvol(trans, root, dir,
>> + dest->root_key.objectid,
>> + dentry->d_name.name,
>> + dentry->d_name.len);
>> + if (ret) {
>> + err = ret;
>> + btrfs_abort_transaction(trans, ret);
>> + goto out_end_trans;
>> + }
>> +
>> + btrfs_record_root_in_trans(trans, dest);
>> +
>> + memset(&dest->root_item.drop_progress, 0,
>> + sizeof(dest->root_item.drop_progress));
>> + dest->root_item.drop_level = 0;
>> + btrfs_set_root_refs(&dest->root_item, 0);
>> +
>> + if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
>> + ret = btrfs_insert_orphan_item(trans,
>> + fs_info->tree_root,
>> + dest->root_key.objectid);
>> + if (ret) {
>> + btrfs_abort_transaction(trans, ret);
>> + err = ret;
>> + goto out_end_trans;
>> + }
>> + }
>> +
>> + ret = btrfs_uuid_tree_rem(trans, fs_info, dest->root_item.uuid,
>> + BTRFS_UUID_KEY_SUBVOL,
>> + dest->root_key.objectid);
>> + if (ret && ret != -ENOENT) {
>> + btrfs_abort_transaction(trans, ret);
>> + err = ret;
>> + goto out_end_trans;
>> + }
>> + if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
>> + ret = btrfs_uuid_tree_rem(trans, fs_info,
>> + dest->root_item.received_uuid,
>> + BTRFS_UUID_KEY_RECEIVED_SUBVOL,
>> + dest->root_key.objectid);
>> + if (ret && ret != -ENOENT) {
>> + btrfs_abort_transaction(trans, ret);
>> + err = ret;
>> + goto out_end_trans;
>> + }
>> + }
>> +
>> +out_end_trans:
>> + trans->block_rsv = NULL;
>> + trans->bytes_reserved = 0;
>> + ret = btrfs_end_transaction(trans);
>> + if (ret && !err)
>> + err = ret;
>> + inode->i_flags |= S_DEAD;
>> +out_release:
>> + btrfs_subvolume_release_metadata(fs_info, &block_rsv);
>> +out_up_write:
>> + up_write(&fs_info->subvol_sem);
>> + if (err) {
>> + spin_lock(&dest->root_item_lock);
>> + root_flags = btrfs_root_flags(&dest->root_item);
>> + btrfs_set_root_flags(&dest->root_item,
>> + root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
>> + spin_unlock(&dest->root_item_lock);
>> + } else {
>> + d_invalidate(dentry);
>> + btrfs_invalidate_inodes(dest);
>> + ASSERT(dest->send_in_progress == 0);
>> +
>> + /* the last ref */
>> + if (dest->ino_cache_inode) {
>> + iput(dest->ino_cache_inode);
>> + dest->ino_cache_inode = NULL;
>> + }
>> + }
>> +
>> + return err;
>> +}
>
> The change separation is still not right. Patch 2+3 should factor out
> btrfs_delete_subvolume and do not any changes to rmdir behaviour. The
> following patch will do what's in the hunk below, with enough reasonging
> why it is so
Ok, I will reorganize the patches/commit log and send again.
>
>> +
>> static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
>> {
>> struct inode *inode = d_inode(dentry);
>> @@ -4398,7 +4537,7 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
>> if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
>> return -ENOTEMPTY;
>> if (btrfs_ino(BTRFS_I(inode)) == BTRFS_FIRST_FREE_OBJECTID)
>> - return -EPERM;
>> + return btrfs_delete_subvolume(dir, dentry);
>>
>> trans = __unlink_start_trans(dir);
>> if (IS_ERR(trans))
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2018-04-11 5:16 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-03-30 6:15 [PATCH v3 0/3] Allow rmdir(2) to delete a subvolume Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 1/3] btrfs: move may_destroy_subvol() from ioctl.c to inode.c Misono Tomohiro
2018-03-30 6:16 ` [PATCH v3 2/3] btrfs: Allow rmdir(2) to delete a subvolume Misono Tomohiro
2018-04-06 14:46 ` David Sterba
2018-04-11 5:16 ` Misono Tomohiro
2018-03-30 6:17 ` [PATCH v3 3/3] btrfs: cleanup btrfs_ioctl_snap_destroy() by using btrfs_delete_subvolume() Misono Tomohiro
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.