1 files changed, 45 insertions, 34 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 653f18aab330..2f71ccf1c3cb 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -15,7 +15,7 @@ static int allocated_blocks = 0;
 static int get_free_block(struct ctree_root *root, u64 *block)
 {
         struct stat st;
-        int ret;
+        int ret = 0;
 
         if (root->alloc_extent->num_used >= root->alloc_extent->num_blocks)
                 return -1;
@@ -30,9 +30,14 @@ static int get_free_block(struct ctree_root *root, u64 *block)
         }
         st.st_size = 0;
         ret = fstat(root->fp, &st);
-        if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE)
+        if (st.st_size < (*block + 1) * CTREE_BLOCKSIZE) {
                 ret = ftruncate(root->fp,
                                 (*block + 1) * CTREE_BLOCKSIZE);
+                if (ret) {
+                        perror("ftruncate");
+                        exit(1);
+                }
+        }
         return ret;
 }
 
@@ -81,11 +86,7 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
         buf = radix_tree_lookup(&root->cache_radix, blocknr);
         if (buf) {
                 buf->count++;
-                if (buf->blocknr != blocknr)
-                        BUG();
-                if (buf->blocknr != buf->node.header.blocknr)
-                        BUG();
-                return buf;
+                goto test;
         }
         buf = alloc_tree_block(root, blocknr);
         if (!buf)
@@ -95,8 +96,11 @@ struct tree_buffer *read_tree_block(struct ctree_root *root, u64 blocknr)
                 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)
+                BUG();
         return buf;
 }
 
@@ -111,36 +115,30 @@ int write_tree_block(struct ctree_root *root, struct tree_buffer *buf)
         ret = pwrite(root->fp, &buf->node, CTREE_BLOCKSIZE, offset);
         if (ret != CTREE_BLOCKSIZE)
                 return ret;
-        if (buf == root->node)
-                return update_root_block(root);
         return 0;
 }
 
-struct ctree_super_block {
-        struct ctree_root_info root_info;
-        struct ctree_root_info extent_info;
-} __attribute__ ((__packed__));
-
 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;
-        INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
-        printf("setup done reading root %p, used %lu\n", root, root->alloc_extent->num_used);
+        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;
 }
 
-struct ctree_root *open_ctree(char *filename)
+struct ctree_root *open_ctree(char *filename, struct ctree_super_block *super)
 {
         struct ctree_root *root = malloc(sizeof(struct ctree_root));
         struct ctree_root *extent_root = malloc(sizeof(struct ctree_root));
-        struct ctree_super_block super;
         int fp;
         int ret;
 
@@ -149,48 +147,61 @@ struct ctree_root *open_ctree(char *filename)
                 free(root);
                 return NULL;
         }
-        ret = pread(fp, &super, sizeof(struct ctree_super_block),
+        ret = pread(fp, super, sizeof(struct ctree_super_block),
                      CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
         if (ret == 0) {
                 ret = mkfs(fp);
                 if (ret)
                         return NULL;
-                ret = pread(fp, &super, sizeof(struct ctree_super_block),
+                ret = pread(fp, super, sizeof(struct ctree_super_block),
                              CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
                 if (ret != sizeof(struct ctree_super_block))
                         return NULL;
         }
         BUG_ON(ret < 0);
-        __setup_root(root, extent_root, &super.root_info, fp);
-        __setup_root(extent_root, extent_root, &super.extent_info, fp);
+        __setup_root(root, extent_root, &super->root_info, fp);
+        __setup_root(extent_root, extent_root, &super->extent_info, fp);
         return root;
 }
 
-int close_ctree(struct ctree_root *root)
+static int __update_root(struct ctree_root *root, struct ctree_root_info *info)
 {
-        close(root->fp);
-        if (root->node)
-                tree_block_release(root, root->node);
-        free(root);
-        printf("on close %d blocks are allocated\n", allocated_blocks);
+        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;
 }
 
-int update_root_block(struct ctree_root *root)
+int write_ctree_super(struct ctree_root *root, struct ctree_super_block *s)
 {
         int ret;
-        u64 root_block = root->node->blocknr;
-
-        ret = pwrite(root->fp, &root_block, sizeof(u64), 0);
-        if (ret != sizeof(u64))
+        __update_root(root, &s->root_info);
+        __update_root(root->extent_root, &s->extent_info);
+        ret = pwrite(root->fp, s, sizeof(*s), CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
+        if (ret != sizeof(*s)) {
+                fprintf(stderr, "failed to write new super block err %d\n", ret);
                 return ret;
+        }
+        return 0;
+}
+
+int close_ctree(struct ctree_root *root)
+{
+        close(root->fp);
+        if (root->node)
+                tree_block_release(root, root->node);
+        if (root->extent_root->node)
+                tree_block_release(root->extent_root, root->extent_root->node);
+        free(root);
+        printf("on close %d blocks are allocated\n", allocated_blocks);
         return 0;
 }
 
 void tree_block_release(struct ctree_root *root, struct tree_buffer *buf)
 {
-        return;
         buf->count--;
+        if (buf->count < 0)
+                BUG();
         if (buf->count == 0) {
                 if (!radix_tree_lookup(&root->cache_radix, buf->blocknr))
                         BUG();