Btrfs: variable block size support

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

1 files changed, 23 insertions, 19 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 3d4bf6833f2a..8d9457b5aef5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -46,7 +46,8 @@ struct btrfs_buffer *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
 {
         struct btrfs_buffer *buf;
         int ret;
-        buf = malloc(sizeof(struct btrfs_buffer));
+
+        buf = malloc(sizeof(struct btrfs_buffer) + root->blocksize);
         if (!buf)
                 return buf;
         allocated_blocks++;
@@ -84,7 +85,7 @@ struct btrfs_buffer *find_tree_block(struct btrfs_root *root, u64 blocknr)
 
 struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
 {
-        loff_t offset = blocknr * BTRFS_BLOCKSIZE;
+        loff_t offset = blocknr * root->blocksize;
         struct btrfs_buffer *buf;
         int ret;
 
@@ -95,8 +96,8 @@ struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
                 buf = alloc_tree_block(root, blocknr);
                 if (!buf)
                         return NULL;
-                ret = pread(root->fp, &buf->node, BTRFS_BLOCKSIZE, offset);
-                if (ret != BTRFS_BLOCKSIZE) {
+                ret = pread(root->fp, &buf->node, root->blocksize, offset);
+                if (ret != root->blocksize) {
                         free(buf);
                         return NULL;
                 }
@@ -127,13 +128,13 @@ int clean_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
 int write_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
 {
         u64 blocknr = buf->blocknr;
-        loff_t offset = blocknr * BTRFS_BLOCKSIZE;
+        loff_t offset = blocknr * root->blocksize;
         int ret;
 
         if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
                 BUG();
-        ret = pwrite(root->fp, &buf->node, BTRFS_BLOCKSIZE, offset);
-        if (ret != BTRFS_BLOCKSIZE)
+        ret = pwrite(root->fp, &buf->node, root->blocksize, offset);
+        if (ret != root->blocksize)
                 return ret;
         return 0;
 }
@@ -215,7 +216,8 @@ int btrfs_commit_transaction(struct btrfs_root *root,
         return ret;
 }
 
-static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
+static int __setup_root(struct btrfs_super_block *super,
+                        struct btrfs_root *root, u64 objectid, int fp)
 {
         INIT_LIST_HEAD(&root->trans);
         INIT_LIST_HEAD(&root->cache);
@@ -223,6 +225,8 @@ static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
         root->fp = fp;
         root->node = NULL;
         root->commit_root = NULL;
+        root->blocksize = btrfs_super_blocksize(super);
+        root->ref_cows = 0;
         memset(&root->current_insert, 0, sizeof(root->current_insert));
         memset(&root->last_insert, 0, sizeof(root->last_insert));
         memset(&root->root_key, 0, sizeof(root->root_key));
@@ -230,19 +234,19 @@ static int __setup_root(struct btrfs_root *root, u64 objectid, int fp)
         return 0;
 }
 
-static int find_and_setup_root(struct btrfs_root *tree_root, u64 objectid,
-                        struct btrfs_root *root, int fp)
+static int find_and_setup_root(struct btrfs_super_block *super,
+                               struct btrfs_root *tree_root, u64 objectid,
+                               struct btrfs_root *root, int fp)
 {
         int ret;
 
-        __setup_root(root, objectid, fp);
+        __setup_root(super, root, objectid, fp);
         ret = btrfs_find_last_root(tree_root, objectid,
                                    &root->root_item, &root->root_key);
         BUG_ON(ret);
 
         root->node = read_tree_block(root,
                                      btrfs_root_blocknr(&root->root_item));
-        root->ref_cows = 0;
         BUG_ON(!root->node);
         return 0;
 }
@@ -277,28 +281,28 @@ struct btrfs_root *open_ctree(char *filename, struct btrfs_super_block *super)
         INIT_RADIX_TREE(&tree_root->cache_radix, GFP_KERNEL);
 
         ret = pread(fp, super, sizeof(struct btrfs_super_block),
-                     BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
+                     BTRFS_SUPER_INFO_OFFSET);
         if (ret == 0 || btrfs_super_root(super) == 0) {
                 printf("making new FS!\n");
-                ret = mkfs(fp, 0, BTRFS_BLOCKSIZE);
+                ret = mkfs(fp, 0, 1024);
                 if (ret)
                         return NULL;
                 ret = pread(fp, super, sizeof(struct btrfs_super_block),
-                             BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
+                             BTRFS_SUPER_INFO_OFFSET);
                 if (ret != sizeof(struct btrfs_super_block))
                         return NULL;
         }
         BUG_ON(ret < 0);
 
-        __setup_root(tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
+        __setup_root(super, tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
         tree_root->node = read_tree_block(tree_root, btrfs_super_root(super));
         BUG_ON(!tree_root->node);
 
-        ret = find_and_setup_root(tree_root, BTRFS_EXTENT_TREE_OBJECTID,
+        ret = find_and_setup_root(super, tree_root, BTRFS_EXTENT_TREE_OBJECTID,
                                   extent_root, fp);
         BUG_ON(ret);
 
-        ret = find_and_setup_root(tree_root, BTRFS_FS_TREE_OBJECTID,
+        ret = find_and_setup_root(super, tree_root, BTRFS_FS_TREE_OBJECTID,
                                   root, fp);
         BUG_ON(ret);
 
@@ -313,7 +317,7 @@ int write_ctree_super(struct btrfs_root *root, struct btrfs_super_block *s)
         int ret;
         btrfs_set_super_root(s, root->tree_root->node->blocknr);
         ret = pwrite(root->fp, s, sizeof(*s),
-                     BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
+                     BTRFS_SUPER_INFO_OFFSET);
         if (ret != sizeof(*s)) {
                 fprintf(stderr, "failed to write new super block err %d\n", ret);
                 return ret;