@@ -971,6 +971,8 @@ BTRFS_SETGET_FUNCS(qgroup_status_flags, struct btrfs_qgroup_status_item,
flags, 64);
BTRFS_SETGET_FUNCS(qgroup_status_rescan, struct btrfs_qgroup_status_item,
rescan, 64);
+BTRFS_SETGET_FUNCS(qgroup_status_enable_gen, struct btrfs_qgroup_status_item,
+ enable_gen, 64);
/* btrfs_qgroup_info_item */
BTRFS_SETGET_FUNCS(qgroup_info_generation, struct btrfs_qgroup_info_item,
@@ -1533,6 +1533,7 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
.rsv_bytes = href->reserved_bytes,
.is_data = true,
.is_inc = true,
+ .generation = trans->transid,
};
if (extent_op)
@@ -1696,6 +1697,7 @@ static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
.rsv_bytes = 0,
.is_data = false,
.is_inc = true,
+ .generation = trans->transid,
};
BUG_ON(!extent_op || !extent_op->update_flags);
@@ -3231,6 +3233,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
.rsv_bytes = 0,
.is_data = is_data,
.is_inc = false,
+ .generation = btrfs_extent_generation(leaf, ei),
};
/* In this branch refs == 1 */
@@ -4866,6 +4869,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_simple_quota_delta delta = {
.root = root_objectid,
.num_bytes = ins->offset,
+ .generation = trans->transid,
.rsv_bytes = 0,
.is_data = true,
.is_inc = true,
@@ -802,6 +802,8 @@ struct btrfs_fs_info {
spinlock_t eb_leak_lock;
struct list_head allocated_ebs;
#endif
+
+ u64 quota_enable_gen;
};
static inline void btrfs_set_last_root_drop_gen(struct btrfs_fs_info *fs_info,
@@ -468,8 +468,9 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info)
btrfs_err(fs_info,
"qgroup generation mismatch, marked as inconsistent");
}
- fs_info->qgroup_flags = btrfs_qgroup_status_flags(l,
- ptr);
+ if (btrfs_fs_incompat(fs_info, SIMPLE_QUOTA))
+ fs_info->quota_enable_gen = btrfs_qgroup_status_enable_gen(l, ptr);
+ fs_info->qgroup_flags = btrfs_qgroup_status_flags(l, ptr);
rescan_progress = btrfs_qgroup_status_rescan(l, ptr);
goto next1;
}
@@ -1115,6 +1116,10 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
ptr = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_qgroup_status_item);
btrfs_set_qgroup_status_generation(leaf, ptr, trans->transid);
+ if (simple) {
+ btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA);
+ btrfs_set_qgroup_status_enable_gen(leaf, ptr, trans->transid);
+ }
btrfs_set_qgroup_status_version(leaf, ptr, BTRFS_QGROUP_STATUS_VERSION);
fs_info->qgroup_flags = BTRFS_QGROUP_STATUS_FLAG_ON;
if (!simple)
@@ -1210,6 +1215,8 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
goto out_free_path;
}
+ fs_info->quota_enable_gen = trans->transid;
+
mutex_unlock(&fs_info->qgroup_ioctl_lock);
/*
* Commit the transaction while not holding qgroup_ioctl_lock, to avoid
@@ -1234,8 +1241,6 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
spin_lock(&fs_info->qgroup_lock);
fs_info->quota_root = quota_root;
set_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
- if (simple)
- btrfs_set_fs_incompat(fs_info, SIMPLE_QUOTA);
spin_unlock(&fs_info->qgroup_lock);
/* Skip rescan for simple qgroups */
@@ -4629,6 +4634,10 @@ int btrfs_record_simple_quota_delta(struct btrfs_fs_info *fs_info,
if (!is_fstree(root))
return 0;
+ /* If the extent predates enabling quotas, don't count it. */
+ if (delta->generation < fs_info->quota_enable_gen)
+ return 0;
+
spin_lock(&fs_info->qgroup_lock);
qgroup = find_qgroup_rb(fs_info, root);
if (!qgroup) {
@@ -241,6 +241,7 @@ struct btrfs_simple_quota_delta {
u64 rsv_bytes; /* The number of bytes reserved for this extent */
bool is_inc; /* Whether we are using or freeing the extent */
bool is_data; /* Whether the extent is data or metadata */
+ u64 generation; /* The generation the extent was created in */
};
static inline u64 btrfs_qgroup_subvolid(u64 qgroupid)
@@ -1230,6 +1230,13 @@ struct btrfs_qgroup_status_item {
* of the scan. It contains a logical address
*/
__le64 rescan;
+
+ /*
+ * the generation when quotas are enabled. Used by simple quotas to
+ * avoid decrementing when freeing an extent that was written before
+ * enable.
+ */
+ __le64 enable_gen;
} __attribute__ ((__packed__));
struct btrfs_qgroup_info_item {
Simple quotas count extents only from the moment the feature is enabled. Therefore, if we do something like: 1. create subvol S 2. write F in S 3. enable quotas 4. remove F 5. write G in S then after 3. and 4. we would expect the simple quota usage of S to be 0 (putting aside some metadata extents that might be written) and after 5., it should be the size of G plus metadata. Therefore, we need to be able to determine whether a particular quota delta we are processing predates simple quota enablement. To do this, store the transaction id when quotas were enabled. In fs_info for immediate use and in the quota status item to make it recoverable on mount. When we see a delta, check if the generation of the extent item is less than that of quota enablement. If so, we should ignore the delta from this extent. Signed-off-by: Boris Burkov <boris@bur.io> --- fs/btrfs/accessors.h | 2 ++ fs/btrfs/extent-tree.c | 4 ++++ fs/btrfs/fs.h | 2 ++ fs/btrfs/qgroup.c | 17 +++++++++++++---- fs/btrfs/qgroup.h | 1 + include/uapi/linux/btrfs_tree.h | 7 +++++++ 6 files changed, 29 insertions(+), 4 deletions(-)