Btrfs: Block sized tree extents and extent deletion

[deliverable/linux.git] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 2f71ccf1c3cb5aac6b29abdf7dd49db00fcd8ce6..14955e4407734b280fc8c30988245ecf5ab80c53 100644 (file)
--- 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;
 }
 
@@ -147,9 +118,12 @@ 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) {
+       if (ret == 0 || super->root_info.tree_root == 0) {
+               printf("making new FS!\n");
                ret = mkfs(fp);
                if (ret)
                        return NULL;
@@ -167,8 +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;
 }
 
@@ -200,6 +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) {