From 524725537023bb25a371722b1329446e5a2adcdb Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 12 Oct 2015 16:05:40 +0800 Subject: [PATCH] btrfs: qgroup: Introduce btrfs_qgroup_reserve_data function Introduce a new function, btrfs_qgroup_reserve_data(), which will use io_tree to accurate qgroup reserve, to avoid reserved space leaking. Signed-off-by: Qu Wenruo Signed-off-by: Chris Mason --- fs/btrfs/extent_io.h | 1 + fs/btrfs/qgroup.c | 49 ++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/qgroup.h | 2 ++ 3 files changed, 52 insertions(+) diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 51e1b7143256..f4c1ae11855f 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -19,6 +19,7 @@ #define EXTENT_NEED_WAIT (1U << 13) #define EXTENT_DAMAGED (1U << 14) #define EXTENT_NORESERVE (1U << 15) +#define EXTENT_QGROUP_RESERVED (1U << 16) #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK) #define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index d904ee1c5349..50662748532a 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -2486,3 +2486,52 @@ btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info) btrfs_queue_work(fs_info->qgroup_rescan_workers, &fs_info->qgroup_rescan_work); } + +/* + * Reserve qgroup space for range [start, start + len). + * + * This function will either reserve space from related qgroups or doing + * nothing if the range is already reserved. + * + * Return 0 for successful reserve + * Return <0 for error (including -EQUOT) + * + * NOTE: this function may sleep for memory allocation. + */ +int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_changeset changeset; + struct ulist_node *unode; + struct ulist_iterator uiter; + int ret; + + if (!root->fs_info->quota_enabled || !is_fstree(root->objectid) || + len == 0) + return 0; + + changeset.bytes_changed = 0; + changeset.range_changed = ulist_alloc(GFP_NOFS); + + ret = set_record_extent_bits(&BTRFS_I(inode)->io_tree, start, + start + len -1, EXTENT_QGROUP_RESERVED, GFP_NOFS, + &changeset); + if (ret < 0) + goto cleanup; + ret = btrfs_qgroup_reserve(root, changeset.bytes_changed); + if (ret < 0) + goto cleanup; + + ulist_free(changeset.range_changed); + return ret; + +cleanup: + /* cleanup already reserved ranges */ + ULIST_ITER_INIT(&uiter); + while ((unode = ulist_next(changeset.range_changed, &uiter))) + clear_extent_bit(&BTRFS_I(inode)->io_tree, unode->val, + unode->aux, EXTENT_QGROUP_RESERVED, 0, 0, NULL, + GFP_NOFS); + ulist_free(changeset.range_changed); + return ret; +} diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index 6387dcfa354c..bd17cc24335c 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -81,4 +81,6 @@ int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid, u64 rfer, u64 excl); #endif +/* New io_tree based accurate qgroup reserve API */ +int btrfs_qgroup_reserve_data(struct inode *inode, u64 start, u64 len); #endif /* __BTRFS_QGROUP__ */