Btrfs: Make the resizer work based on shrinking and growing devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c49592c..6540095 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -187,6 +187,7 @@
if (!cache)
goto out;
+
total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
free_space_cache = &root->fs_info->free_space_cache;
@@ -196,7 +197,7 @@
goto out;
last = max(search_start, cache->key.objectid);
- if (!block_group_bits(cache, data)) {
+ if (!block_group_bits(cache, data) || cache->ro) {
goto new_group;
}
@@ -221,6 +222,8 @@
continue;
}
spin_unlock_irq(&free_space_cache->lock);
+ if (cache->ro)
+ goto new_group;
if (start + num > cache->key.objectid + cache->key.offset)
goto new_group;
if (start + num > total_fs_bytes)
@@ -319,7 +322,7 @@
if (search_start && search_start < total_fs_bytes) {
struct btrfs_block_group_cache *shint;
shint = btrfs_lookup_block_group(info, search_start);
- if (shint && block_group_bits(shint, data)) {
+ if (shint && block_group_bits(shint, data) && !shint->ro) {
used = btrfs_block_group_used(&shint->item);
if (used + shint->pinned <
div_factor(shint->key.offset, factor)) {
@@ -327,7 +330,7 @@
}
}
}
- if (hint && block_group_bits(hint, data) &&
+ if (hint && !hint->ro && block_group_bits(hint, data) &&
hint->key.objectid < total_fs_bytes) {
used = btrfs_block_group_used(&hint->item);
if (used + hint->pinned <
@@ -364,7 +367,7 @@
if (cache->key.objectid > total_fs_bytes)
break;
- if (block_group_bits(cache, data)) {
+ if (!cache->ro && block_group_bits(cache, data)) {
if (full_search)
free_check = cache->key.offset;
else
@@ -1020,6 +1023,7 @@
if (found) {
found->total_bytes += total_bytes;
found->bytes_used += bytes_used;
+ found->full = 0;
WARN_ON(found->total_bytes < found->bytes_used);
*space_info = found;
return 0;
@@ -1700,7 +1704,6 @@
u64 super_used;
u64 root_used;
u64 search_start = 0;
- u64 new_hint;
u64 alloc_profile;
u32 sizes[2];
struct btrfs_fs_info *info = root->fs_info;
@@ -1724,7 +1727,7 @@
data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
}
again:
- if (root->ref_cows) {
+ if (root != root->fs_info->extent_root) {
if (!(data & BTRFS_BLOCK_GROUP_METADATA)) {
ret = do_chunk_alloc(trans, root->fs_info->extent_root,
2 * 1024 * 1024,
@@ -1738,10 +1741,6 @@
BUG_ON(ret);
}
- new_hint = max(hint_byte, root->fs_info->alloc_start);
- if (new_hint < btrfs_super_total_bytes(&info->super_copy))
- hint_byte = new_hint;
-
WARN_ON(num_bytes < root->sectorsize);
ret = find_free_extent(trans, root, num_bytes, empty_size,
search_start, search_end, hint_byte, ins,
@@ -2473,15 +2472,16 @@
return ret;
}
-int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size)
+int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
{
struct btrfs_trans_handle *trans;
struct btrfs_root *tree_root = root->fs_info->tree_root;
struct btrfs_path *path;
u64 cur_byte;
u64 total_found;
+ u64 shrink_last_byte;
+ struct btrfs_block_group_cache *shrink_block_group;
struct btrfs_fs_info *info = root->fs_info;
- struct extent_io_tree *block_group_cache;
struct btrfs_key key;
struct btrfs_key found_key;
struct extent_buffer *leaf;
@@ -2489,17 +2489,29 @@
int ret;
int progress = 0;
- btrfs_set_super_total_bytes(&info->super_copy, new_size);
- clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,
- GFP_NOFS);
- block_group_cache = &info->block_group_cache;
+ shrink_block_group = btrfs_lookup_block_group(root->fs_info,
+ shrink_start);
+ BUG_ON(!shrink_block_group);
+
+ shrink_last_byte = shrink_start + shrink_block_group->key.offset;
+
+ shrink_block_group->space_info->total_bytes -=
+ shrink_block_group->key.offset;
+printk("shrink_extent_tree %Lu -> %Lu type %Lu\n", shrink_start, shrink_last_byte, shrink_block_group->flags);
path = btrfs_alloc_path();
root = root->fs_info->extent_root;
path->reada = 2;
again:
+ trans = btrfs_start_transaction(root, 1);
+ do_chunk_alloc(trans, root->fs_info->extent_root,
+ btrfs_block_group_used(&shrink_block_group->item) +
+ 2 * 1024 * 1024, shrink_block_group->flags);
+ btrfs_end_transaction(trans, root);
+ shrink_block_group->ro = 1;
+
total_found = 0;
- key.objectid = new_size;
+ key.objectid = shrink_start;
key.offset = 0;
key.type = 0;
cur_byte = key.objectid;
@@ -2511,10 +2523,12 @@
ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
if (ret < 0)
goto out;
+
if (ret == 0) {
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (found_key.objectid + found_key.offset > new_size) {
+ if (found_key.objectid + found_key.offset > shrink_start &&
+ found_key.objectid < shrink_last_byte) {
cur_byte = found_key.objectid;
key.objectid = cur_byte;
}
@@ -2543,6 +2557,9 @@
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ if (found_key.objectid >= shrink_last_byte)
+ break;
+
if (progress && need_resched()) {
memcpy(&key, &found_key, sizeof(key));
mutex_unlock(&root->fs_info->fs_mutex);
@@ -2583,68 +2600,31 @@
goto again;
}
+ /*
+ * we've freed all the extents, now remove the block
+ * group item from the tree
+ */
trans = btrfs_start_transaction(root, 1);
- key.objectid = new_size;
- key.offset = 0;
- key.type = 0;
- while(1) {
- u64 ptr;
+ memcpy(&key, &shrink_block_group->key, sizeof(key));
- ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
- if (ret < 0)
- goto out;
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret > 0)
+ ret = -EIO;
+ if (ret < 0)
+ goto out;
- leaf = path->nodes[0];
- nritems = btrfs_header_nritems(leaf);
-bg_next:
- if (path->slots[0] >= nritems) {
- ret = btrfs_next_leaf(root, path);
- if (ret < 0)
- break;
- if (ret == 1) {
- ret = 0;
- break;
- }
- leaf = path->nodes[0];
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ leaf = path->nodes[0];
+ nritems = btrfs_header_nritems(leaf);
+ btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+ kfree(shrink_block_group);
- /*
- * btrfs_next_leaf doesn't cow buffers, we have to
- * do the search again
- */
- memcpy(&key, &found_key, sizeof(key));
- btrfs_release_path(root, path);
- goto resched_check;
- }
+ clear_extent_bits(&info->block_group_cache, found_key.objectid,
+ found_key.objectid + found_key.offset - 1,
+ (unsigned int)-1, GFP_NOFS);
- btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- if (btrfs_key_type(&found_key) != BTRFS_BLOCK_GROUP_ITEM_KEY) {
- printk("shrinker found key %Lu %u %Lu\n",
- found_key.objectid, found_key.type,
- found_key.offset);
- path->slots[0]++;
- goto bg_next;
- }
- ret = get_state_private(&info->block_group_cache,
- found_key.objectid, &ptr);
- if (!ret)
- kfree((void *)(unsigned long)ptr);
-
- clear_extent_bits(&info->block_group_cache, found_key.objectid,
- found_key.objectid + found_key.offset - 1,
- (unsigned int)-1, GFP_NOFS);
-
- key.objectid = found_key.objectid + 1;
- btrfs_del_item(trans, root, path);
- btrfs_release_path(root, path);
-resched_check:
- if (need_resched()) {
- mutex_unlock(&root->fs_info->fs_mutex);
- cond_resched();
- mutex_lock(&root->fs_info->fs_mutex);
- }
- }
- clear_extent_dirty(&info->free_space_cache, new_size, (u64)-1,
+ btrfs_del_item(trans, root, path);
+ clear_extent_dirty(&info->free_space_cache,
+ shrink_start, shrink_last_byte - 1,
GFP_NOFS);
btrfs_commit_transaction(trans, root);
out:
@@ -2652,13 +2632,6 @@
return ret;
}
-int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 new_size)
-{
- btrfs_set_super_total_bytes(&root->fs_info->super_copy, new_size);
- return 0;
-}
-
int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
struct btrfs_key *key)
{
@@ -2726,7 +2699,7 @@
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
- cache = kmalloc(sizeof(*cache), GFP_NOFS);
+ cache = kzalloc(sizeof(*cache), GFP_NOFS);
if (!cache) {
ret = -ENOMEM;
break;
@@ -2736,8 +2709,6 @@
btrfs_item_ptr_offset(leaf, path->slots[0]),
sizeof(cache->item));
memcpy(&cache->key, &found_key, sizeof(found_key));
- cache->cached = 0;
- cache->pinned = 0;
key.objectid = found_key.objectid + found_key.offset;
btrfs_release_path(root, path);
@@ -2789,12 +2760,10 @@
extent_root = root->fs_info->extent_root;
block_group_cache = &root->fs_info->block_group_cache;
- cache = kmalloc(sizeof(*cache), GFP_NOFS);
+ cache = kzalloc(sizeof(*cache), GFP_NOFS);
BUG_ON(!cache);
cache->key.objectid = chunk_offset;
cache->key.offset = size;
- cache->cached = 0;
- cache->pinned = 0;
btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
memset(&cache->item, 0, sizeof(cache->item));