Btrfs: hooks to reserve qgroup space

Like block reserves, reserve a small piece of space on each
transaction start and for delalloc. These are the hooks that
can actually return EDQUOT to the user.
The amount of space reserved is tracked in the transaction
handle.

Signed-off-by: Arne Jansen <sensille@gmx.net>

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c08337a83aced70b82c37b48569fbcdb581a8f22..2ce16f97730a7c3986642f19b2e8f7d035d50227 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4565,6 +4565,13 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
        csum_bytes = BTRFS_I(inode)->csum_bytes;
        spin_unlock(&BTRFS_I(inode)->lock);
 
+       if (root->fs_info->quota_enabled) {
+               ret = btrfs_qgroup_reserve(root, num_bytes +
+                                          nr_extents * root->leafsize);
+               if (ret)
+                       return ret;
+       }
+
        ret = reserve_metadata_bytes(root, block_rsv, to_reserve, flush);
        if (ret) {
                u64 to_free = 0;
@@ -4643,6 +4650,11 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
 
        trace_btrfs_space_reservation(root->fs_info, "delalloc",
                                      btrfs_ino(inode), to_free, 0);
+       if (root->fs_info->quota_enabled) {
+               btrfs_qgroup_free(root, num_bytes +
+                                       dropped * root->leafsize);
+       }
+
        btrfs_block_rsv_release(root, &root->fs_info->delalloc_block_rsv,
                                to_free);
 }

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 21c768cb443f7624585b66992cc0e045a26e2ab5..f1e29fbd5317aeea51880645b4f7d6589f8b0c99 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -295,6 +295,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
        struct btrfs_transaction *cur_trans;
        u64 num_bytes = 0;
        int ret;
+       u64 qgroup_reserved = 0;
 
        if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
                return ERR_PTR(-EROFS);
@@ -313,6 +314,14 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
         * the appropriate flushing if need be.
         */
        if (num_items > 0 && root != root->fs_info->chunk_root) {
+               if (root->fs_info->quota_enabled &&
+                   is_fstree(root->root_key.objectid)) {
+                       qgroup_reserved = num_items * root->leafsize;
+                       ret = btrfs_qgroup_reserve(root, qgroup_reserved);
+                       if (ret)
+                               return ERR_PTR(ret);
+               }
+
                num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
                ret = btrfs_block_rsv_add(root,
                                          &root->fs_info->trans_block_rsv,
@@ -351,6 +360,7 @@ again:
        h->block_rsv = NULL;
        h->orig_rsv = NULL;
        h->aborted = 0;
+       h->qgroup_reserved = qgroup_reserved;
        h->delayed_ref_elem.seq = 0;
        INIT_LIST_HEAD(&h->qgroup_ref_list);
 
@@ -524,6 +534,12 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
         * end_transaction. Subvolume quota depends on this.
         */
        WARN_ON(trans->root != root);
+
+       if (trans->qgroup_reserved) {
+               btrfs_qgroup_free(root, trans->qgroup_reserved);
+               trans->qgroup_reserved = 0;
+       }
+
        while (count < 2) {
                unsigned long cur = trans->delayed_ref_updates;
                trans->delayed_ref_updates = 0;

diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 16ba00842c3852c7a1a9c3fb4f88270cb4d7c5fa..2759e0572c5c242c4e6ff6bc961331af95bff111 100644 (file)
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -50,6 +50,7 @@ struct btrfs_transaction {
 struct btrfs_trans_handle {
        u64 transid;
        u64 bytes_reserved;
+       u64 qgroup_reserved;
        unsigned long use_count;
        unsigned long blocks_reserved;
        unsigned long blocks_used;