Btrfs: Block sized tree extents and extent deletion

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 31 insertions, 59 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a696a4278ac5..14955e440773 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 @@ struct tree_buffer *alloc_tree_block(struct ctree_root *root, u64 blocknr)
         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 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
         buf = radix_tree_lookup(&root->cache_radix, blocknr);
         if (buf) {
                 buf->count++;
-                goto test;
-        }
-        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;
+        } 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;
+                }
         }
-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 @@ int write_tree_block(struct ctree_root *root, struct tree_buffer *buf)
 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 @@ struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super)
                 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 @@ struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super)
 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 @@ int close_ctree(struct ctree_root *root)
 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) {