[PATCH v3 21/22] btrfs-progs: convert: Strictly avoid meta or system chunk allocation
From: Qu Wenruo <hidden>
Date: 2016-01-29 05:16:44
Subsystem:
the rest · Maintainer:
Linus Torvalds
Before this patch, btrfs-convert only rely on large enough initial system/metadata chunk size to ensure no newer system/meta chunk will be created. But that's not safe enough. So add two new members in fs_info, avoid_sys/meta_chunk_alloc flags to prevent any newer system or meta chunks to be created before init_btrfs_v2(). Signed-off-by: Qu Wenruo <redacted> Signed-off-by: David Sterba <dsterba@suse.com> --- btrfs-convert.c | 9 +++++++++ ctree.h | 3 +++ extent-tree.c | 10 ++++++++++ 3 files changed, 22 insertions(+)
diff --git a/btrfs-convert.c b/btrfs-convert.c
index efa3b02..333f413 100644
--- a/btrfs-convert.c
+++ b/btrfs-convert.c@@ -2322,6 +2322,13 @@ static int init_btrfs_v2(struct btrfs_mkfs_config *cfg, struct btrfs_root *root, struct btrfs_fs_info *fs_info = root->fs_info; int ret; + /* + * Don't alloc any metadata/system chunk, as we don't want + * any meta/sys chunk allcated before all data chunks are inserted. + * Or we screw up the chunk layout just like the old implement. + */ + fs_info->avoid_sys_chunk_alloc = 1; + fs_info->avoid_meta_chunk_alloc = 1; trans = btrfs_start_transaction(root, 1); BUG_ON(!trans); ret = btrfs_fix_block_accounting(trans, root);
@@ -2359,6 +2366,8 @@ static int init_btrfs_v2(struct btrfs_mkfs_config *cfg, struct btrfs_root *root, goto err; ret = btrfs_commit_transaction(trans, root); + fs_info->avoid_sys_chunk_alloc = 0; + fs_info->avoid_meta_chunk_alloc = 0; err: return ret; }
diff --git a/ctree.h b/ctree.h
index 1443746..187bd27 100644
--- a/ctree.h
+++ b/ctree.h@@ -1030,6 +1030,9 @@ struct btrfs_fs_info { unsigned int quota_enabled:1; unsigned int suppress_check_block_errors:1; unsigned int ignore_fsid_mismatch:1; + unsigned int avoid_meta_chunk_alloc:1; + unsigned int avoid_sys_chunk_alloc:1; + int (*free_extent_hook)(struct btrfs_trans_handle *trans, struct btrfs_root *root,
diff --git a/extent-tree.c b/extent-tree.c
index 93b1945..e7c61b1 100644
--- a/extent-tree.c
+++ b/extent-tree.c@@ -1904,6 +1904,16 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans, thresh) return 0; + /* + * Avoid allocating given chunk type + */ + if (extent_root->fs_info->avoid_meta_chunk_alloc && + (flags & BTRFS_BLOCK_GROUP_METADATA)) + return 0; + if (extent_root->fs_info->avoid_sys_chunk_alloc && + (flags & BTRFS_BLOCK_GROUP_SYSTEM)) + return 0; + ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, space_info->flags); if (ret == -ENOSPC) {
--
2.7.0