Btrfs: Block sized tree extents and extent deletion
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a696a42..14955e4 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -12,33 +12,13 @@
static int allocated_blocks = 0;
-static int get_free_block(struct ctree_root *root, u64 *block)
+static int check_tree_block(struct ctree_root *root, struct tree_buffer *buf)
{
- struct stat st;
- int ret = 0;
-
- if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks)
- return -1;
-
- *block = root->alloc_extent->blocknr + root->alloc_extent->num_used;
- root->alloc_extent->num_used += 1;
- if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks) {
- struct alloc_extent *ae = root->alloc_extent;
- root->alloc_extent = root->reserve_extent;
- root->reserve_extent = ae;
- ae->num_blocks = 0;
- }
- st.st_size = 0;
- ret = fstat(root->fp, &st);
- if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE) {
- ret = ftruncate(root->fp,
- (*block + 1) * CTREE_BLOCKSIZE);
- if (ret) {
- perror("ftruncate");
- exit(1);
- }
- }
- return ret;
+ if (buf->blocknr != buf->node.header.blocknr)
+ BUG();
+ if (root->node && buf->node.header.parentid != root->node->node.header.parentid)
+ BUG();
+ return 0;
}
struct tree_buffer *alloc_tree_block(struct ctree_root *root, u64 blocknr)
@@ -61,22 +41,23 @@
return buf;
}
-struct tree_buffer *alloc_free_block(struct ctree_root *root)
+struct tree_buffer *find_tree_block(struct ctree_root *root, u64 blocknr)
{
- u64 free_block;
- int ret;
- struct tree_buffer * buf;
- ret = get_free_block(root, &free_block);
- if (ret) {
- BUG();
- return NULL;
+ struct tree_buffer *buf;
+ buf = radix_tree_lookup(&root->cache_radix, blocknr);
+ if (buf) {
+ buf->count++;
+ } else {
+ buf = alloc_tree_block(root, blocknr);
+ if (!buf) {
+ BUG();
+ return NULL;
+ }
}
- buf = alloc_tree_block(root, free_block);
- if (!buf)
- BUG();
return buf;
}
+
struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
{
loff_t offset = blocknr * CTREE_BLOCKSIZE;
@@ -86,20 +67,17 @@
buf = radix_tree_lookup(&root->cache_radix, blocknr);
if (buf) {
buf->count++;
- goto test;
+ } else {
+ buf = alloc_tree_block(root, blocknr);
+ if (!buf)
+ return NULL;
+ ret = pread(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
+ if (ret != CTREE_BLOCKSIZE) {
+ free(buf);
+ return NULL;
+ }
}
- buf = alloc_tree_block(root, blocknr);
- if (!buf)
- return NULL;
- ret = pread(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
- if (ret != CTREE_BLOCKSIZE) {
- free(buf);
- return NULL;
- }
-test:
- if (buf->blocknr != buf->node.header.blocknr)
- BUG();
- if (root->node && buf->node.header.parentid != root->node->node.header.parentid)
+ if (check_tree_block(root, buf))
BUG();
return buf;
}
@@ -121,17 +99,10 @@
static int __setup_root(struct ctree_root *root, struct ctree_root *extent_root,
struct ctree_root_info *info, int fp)
{
- INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
root->fp = fp;
root->node = NULL;
root->node = read_tree_block(root, info->tree_root);
root->extent_root = extent_root;
- memcpy(&root->ai1, &info->alloc_extent, sizeof(info->alloc_extent));
- memcpy(&root->ai2, &info->reserve_extent, sizeof(info->reserve_extent));
- root->alloc_extent = &root->ai1;
- root->reserve_extent = &root->ai2;
- printf("setup done reading root %p, used %lu available %lu\n", root, root->alloc_extent->num_used, root->alloc_extent->num_blocks);
- printf("setup done reading root %p, reserve used %lu available %lu\n", root, root->reserve_extent->num_used, root->reserve_extent->num_blocks);
return 0;
}
@@ -147,6 +118,8 @@
free(root);
return NULL;
}
+ INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
+ INIT_RADIX_TREE(&extent_root->cache_radix, GFP_KERNEL);
ret = pread(fp, super, sizeof(struct ctree_super_block),
CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret == 0 || super->root_info.tree_root == 0) {
@@ -168,8 +141,6 @@
static int __update_root(struct ctree_root *root, struct ctree_root_info *info)
{
info->tree_root = root->node->blocknr;
- memcpy(&info->alloc_extent, root->alloc_extent, sizeof(struct alloc_extent));
- memcpy(&info->reserve_extent, root->reserve_extent, sizeof(struct alloc_extent));
return 0;
}
@@ -201,6 +172,7 @@
void tree_block_release(struct ctree_root *root, struct tree_buffer *buf)
{
buf->count--;
+ write_tree_block(root, buf);
if (buf->count < 0)
BUG();
if (buf->count == 0) {