openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Btrfs: Fix cache_block_group to catch holes at the start of the group 

Cache block group was overly complex and missed free blocks at the very start
of the group.  This patch simplifies things significantly.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Yan 2007-09-14 16:15:28 -04:00 committed by David Woodhouse
parent 6af858b24c
commit 7d7d6068be
1 changed files with 35 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

65
fs/btrfs/extent-tree.c
View File

@ -39,6 +39,7 @@ static int cache_block_group(struct btrfs_root *root,
u64 i;
u64 last = 0;
u64 hole_size;
u64 first_free;
int found = 0;
root = root->fs_info->extent_root;
@ -51,16 +52,22 @@ static int cache_block_group(struct btrfs_root *root,
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
path->reada = 2;
first_free = block_group->key.objectid;
key.objectid = block_group->key.objectid;
key.flags = 0;
key.offset = 0;
btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
return ret;
if (ret && path->slots[0] > 0)
path->slots[0]--;
while(1) {
leaf = btrfs_buffer_leaf(path->nodes[0]);
slot = path->slots[0];
@ -71,50 +78,48 @@ static int cache_block_group(struct btrfs_root *root,
if (ret == 0) {
continue;
} else {
if (found) {
hole_size = block_group->key.objectid +
block_group->key.offset - last;
} else {
last = block_group->key.objectid;
hole_size = block_group->key.offset;
}
for (i = 0; i < hole_size; i++) {
set_radix_bit(extent_radix,
last + i);
}
break;
}
}
btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
if (key.objectid < block_group->key.objectid) {
if (key.objectid + key.offset > first_free)
first_free = key.objectid + key.offset;
goto next;
}
if (key.objectid >= block_group->key.objectid +
block_group->key.offset) {
if (found) {
hole_size = block_group->key.objectid +
block_group->key.offset - last;
} else {
last = block_group->key.objectid;
hole_size = block_group->key.offset;
break;
}
if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
if (!found) {
last = first_free;
found = 1;
}
hole_size = key.objectid - last;
for (i = 0; i < hole_size; i++) {
set_radix_bit(extent_radix, last + i);
}
break;
}
if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
if (!found) {
last = key.objectid + key.offset;
found = 1;
} else {
hole_size = key.objectid - last;
for (i = 0; i < hole_size; i++) {
set_radix_bit(extent_radix, last + i);
}
last = key.objectid + key.offset;
}
last = key.objectid + key.offset;
}
next:
path->slots[0]++;
}
if (!found)
last = first_free;
if (block_group->key.objectid +
block_group->key.offset > last) {
hole_size = block_group->key.objectid +
block_group->key.offset - last;
for (i = 0; i < hole_size; i++) {
set_radix_bit(extent_radix,
last + i);
}
}
block_group->cached = 1;
err:
btrfs_free_path(path);