Mountable btrfs, with readdir

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

1 files changed, 83 insertions, 198 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 05637f9fd7c7..df2061a735cd 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1,165 +1,67 @@
-#define _XOPEN_SOURCE 500
-#include <stdio.h>
-#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include "kerncompat.h"
-#include "radix-tree.h"
+#include <linux/module.h>
+#include <linux/fs.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
 
-static int allocated_blocks = 0;
-int cache_max = 10000;
-
-static int check_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
+static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
 {
-        if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
+        struct btrfs_node *node = btrfs_buffer_node(buf);
+        if (buf->b_blocknr != btrfs_header_blocknr(&node->header))
                 BUG();
-        if (root->node && btrfs_header_parentid(&buf->node.header) !=
-            btrfs_header_parentid(&root->node->node.header))
+        if (root->node && btrfs_header_parentid(&node->header) !=
+            btrfs_header_parentid(btrfs_buffer_header(root->node)))
                 BUG();
         return 0;
 }
 
-static int free_some_buffers(struct btrfs_root *root)
+struct buffer_head *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
 {
-        struct list_head *node, *next;
-        struct btrfs_buffer *b;
-        if (root->fs_info->cache_size < cache_max)
-                return 0;
-        list_for_each_safe(node, next, &root->fs_info->cache) {
-                b = list_entry(node, struct btrfs_buffer, cache);
-                if (b->count == 1) {
-                        BUG_ON(!list_empty(&b->dirty));
-                        list_del_init(&b->cache);
-                        btrfs_block_release(root, b);
-                        if (root->fs_info->cache_size < cache_max)
-                                break;
-                }
-        }
-        return 0;
+        return sb_getblk(root->fs_info->sb, blocknr);
 }
 
-struct btrfs_buffer *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
+struct buffer_head *find_tree_block(struct btrfs_root *root, u64 blocknr)
 {
-        struct btrfs_buffer *buf;
-        int ret;
-
-        buf = malloc(sizeof(struct btrfs_buffer) + root->blocksize);
-        if (!buf)
-                return buf;
-        allocated_blocks++;
-        buf->blocknr = blocknr;
-        buf->count = 2;
-        INIT_LIST_HEAD(&buf->dirty);
-        free_some_buffers(root);
-        radix_tree_preload(GFP_KERNEL);
-        ret = radix_tree_insert(&root->fs_info->cache_radix, blocknr, buf);
-        radix_tree_preload_end();
-        list_add_tail(&buf->cache, &root->fs_info->cache);
-        root->fs_info->cache_size++;
-        if (ret) {
-                free(buf);
-                return NULL;
-        }
-        return buf;
+        return sb_getblk(root->fs_info->sb, blocknr);
 }
 
-struct btrfs_buffer *find_tree_block(struct btrfs_root *root, u64 blocknr)
+struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
 {
-        struct btrfs_buffer *buf;
-        buf = radix_tree_lookup(&root->fs_info->cache_radix, blocknr);
-        if (buf) {
-                buf->count++;
-        } else {
-                buf = alloc_tree_block(root, blocknr);
-                if (!buf) {
-                        BUG();
-                        return NULL;
-                }
-        }
-        return buf;
-}
-
-struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
-{
-        loff_t offset = blocknr * root->blocksize;
-        struct btrfs_buffer *buf;
-        int ret;
+        struct buffer_head *buf = sb_bread(root->fs_info->sb, blocknr);
 
-        buf = radix_tree_lookup(&root->fs_info->cache_radix, blocknr);
-        if (buf) {
-                buf->count++;
-        } else {
-                buf = alloc_tree_block(root, blocknr);
-                if (!buf)
-                        return NULL;
-                ret = pread(root->fs_info->fp, &buf->node, root->blocksize,
-                            offset);
-                if (ret != root->blocksize) {
-                        free(buf);
-                        return NULL;
-                }
-        }
+        if (!buf)
+                return buf;
         if (check_tree_block(root, buf))
                 BUG();
         return buf;
 }
 
 int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                     struct btrfs_buffer *buf)
+                     struct buffer_head *buf)
 {
-        if (!list_empty(&buf->dirty))
-                return 0;
-        list_add_tail(&buf->dirty, &root->fs_info->trans);
-        buf->count++;
+        mark_buffer_dirty(buf);
         return 0;
 }
 
 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                     struct btrfs_buffer *buf)
+                     struct buffer_head *buf)
 {
-        if (!list_empty(&buf->dirty)) {
-                list_del_init(&buf->dirty);
-                btrfs_block_release(root, buf);
-        }
+        clear_buffer_dirty(buf);
         return 0;
 }
 
 int write_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                     struct btrfs_buffer *buf)
+                     struct buffer_head *buf)
 {
-        u64 blocknr = buf->blocknr;
-        loff_t offset = blocknr * root->blocksize;
-        int ret;
-
-        if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
-                BUG();
-        ret = pwrite(root->fs_info->fp, &buf->node, root->blocksize, offset);
-        if (ret != root->blocksize)
-                return ret;
+        mark_buffer_dirty(buf);
         return 0;
 }
 
 static int __commit_transaction(struct btrfs_trans_handle *trans, struct
                                 btrfs_root *root)
 {
-        struct btrfs_buffer *b;
-        int ret = 0;
-        int wret;
-        while(!list_empty(&root->fs_info->trans)) {
-                b = list_entry(root->fs_info->trans.next, struct btrfs_buffer,
-                               dirty);
-                list_del_init(&b->dirty);
-                wret = write_tree_block(trans, root, b);
-                if (wret)
-                        ret = wret;
-                btrfs_block_release(root, b);
-        }
-        return ret;
+        filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
+        return 0;
 }
 
 static int commit_tree_roots(struct btrfs_trans_handle *trans,
@@ -172,17 +74,17 @@ static int commit_tree_roots(struct btrfs_trans_handle *trans,
         struct btrfs_root *inode_root = fs_info->inode_root;
 
         btrfs_set_root_blocknr(&inode_root->root_item,
-                               inode_root->node->blocknr);
+                               inode_root->node->b_blocknr);
         ret = btrfs_update_root(trans, tree_root,
                                 &inode_root->root_key,
                                 &inode_root->root_item);
         BUG_ON(ret);
         while(1) {
                 old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
-                if (old_extent_block == extent_root->node->blocknr)
+                if (old_extent_block == extent_root->node->b_blocknr)
                         break;
                 btrfs_set_root_blocknr(&extent_root->root_item,
-                                       extent_root->node->blocknr);
+                                       extent_root->node->b_blocknr);
                 ret = btrfs_update_root(trans, tree_root,
                                         &extent_root->root_key,
                                         &extent_root->root_item);
@@ -195,7 +97,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
                              btrfs_root *root, struct btrfs_super_block *s)
 {
         int ret = 0;
-        struct btrfs_buffer *snap = root->commit_root;
+        struct buffer_head *snap = root->commit_root;
         struct btrfs_key snap_key;
 
         if (root->commit_root == root->node)
@@ -204,7 +106,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
         memcpy(&snap_key, &root->root_key, sizeof(snap_key));
         root->root_key.offset++;
 
-        btrfs_set_root_blocknr(&root->root_item, root->node->blocknr);
+        btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
         ret = btrfs_insert_root(trans, root->fs_info->tree_root,
                                 &root->root_key, &root->root_item);
         BUG_ON(ret);
@@ -220,7 +122,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
         btrfs_finish_extent_commit(trans, root->fs_info->tree_root);
 
         root->commit_root = root->node;
-        root->node->count++;
+        get_bh(root->node);
         ret = btrfs_drop_snapshot(trans, root, snap);
         BUG_ON(ret);
 
@@ -234,7 +136,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, struct
 static int __setup_root(struct btrfs_super_block *super,
                         struct btrfs_root *root,
                         struct btrfs_fs_info *fs_info,
-                        u64 objectid, int fp)
+                        u64 objectid)
 {
         root->node = NULL;
         root->commit_root = NULL;
@@ -250,11 +152,11 @@ static int find_and_setup_root(struct btrfs_super_block *super,
                                struct btrfs_root *tree_root,
                                struct btrfs_fs_info *fs_info,
                                u64 objectid,
-                               struct btrfs_root *root, int fp)
+                               struct btrfs_root *root)
 {
         int ret;
 
-        __setup_root(super, root, fs_info, objectid, fp);
+        __setup_root(super, root, fs_info, objectid);
         ret = btrfs_find_last_root(tree_root, objectid,
                                    &root->root_item, &root->root_key);
         BUG_ON(ret);
@@ -265,32 +167,26 @@ static int find_and_setup_root(struct btrfs_super_block *super,
         return 0;
 }
 
-struct btrfs_root *open_ctree(char *filename, struct btrfs_super_block *super)
+struct btrfs_root *open_ctree(struct super_block *sb,
+                              struct buffer_head *sb_buffer,
+                              struct btrfs_super_block *disk_super)
 {
-        int fp;
-
-        fp = open(filename, O_CREAT | O_RDWR, 0600);
-        if (fp < 0) {
-                return NULL;
-        }
-        return open_ctree_fd(fp, super);
-}
-
-struct btrfs_root *open_ctree_fd(int fp, struct btrfs_super_block *super)
-{
-        struct btrfs_root *root = malloc(sizeof(struct btrfs_root));
-        struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
-        struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
-        struct btrfs_root *inode_root = malloc(sizeof(struct btrfs_root));
-        struct btrfs_fs_info *fs_info = malloc(sizeof(*fs_info));
+        struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root),
+                                          GFP_NOFS);
+        struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
+                                                 GFP_NOFS);
+        struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
+                                               GFP_NOFS);
+        struct btrfs_root *inode_root = kmalloc(sizeof(struct btrfs_root),
+                                                GFP_NOFS);
+        struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
+                                                GFP_NOFS);
         int ret;
 
-        INIT_RADIX_TREE(&fs_info->cache_radix, GFP_KERNEL);
+        /* FIXME: don't be stupid */
+        if (!btrfs_super_root(disk_super))
+                return NULL;
         INIT_RADIX_TREE(&fs_info->pinned_radix, GFP_KERNEL);
-        INIT_LIST_HEAD(&fs_info->trans);
-        INIT_LIST_HEAD(&fs_info->cache);
-        fs_info->cache_size = 0;
-        fs_info->fp = fp;
         fs_info->running_transaction = NULL;
         fs_info->fs_root = root;
         fs_info->tree_root = tree_root;
@@ -298,36 +194,31 @@ struct btrfs_root *open_ctree_fd(int fp, struct btrfs_super_block *super)
         fs_info->inode_root = inode_root;
         fs_info->last_inode_alloc = 0;
         fs_info->last_inode_alloc_dirid = 0;
-        fs_info->disk_super = super;
+        fs_info->disk_super = disk_super;
+        fs_info->sb_buffer = sb_buffer;
+        fs_info->sb = sb;
         memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
         memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
 
-        ret = pread(fp, super, sizeof(struct btrfs_super_block),
-                     BTRFS_SUPER_INFO_OFFSET);
-        if (ret == 0 || btrfs_super_root(super) == 0) {
-                BUG();
-                return NULL;
-        }
-        BUG_ON(ret < 0);
-
-        __setup_root(super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID, fp);
-        tree_root->node = read_tree_block(tree_root, btrfs_super_root(super));
+        __setup_root(disk_super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
+        tree_root->node = read_tree_block(tree_root,
+                                          btrfs_super_root(disk_super));
         BUG_ON(!tree_root->node);
 
-        ret = find_and_setup_root(super, tree_root, fs_info,
-                                  BTRFS_EXTENT_TREE_OBJECTID, extent_root, fp);
+        ret = find_and_setup_root(disk_super, tree_root, fs_info,
+                                  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
         BUG_ON(ret);
 
-        ret = find_and_setup_root(super, tree_root, fs_info,
-                                  BTRFS_INODE_MAP_OBJECTID, inode_root, fp);
+        ret = find_and_setup_root(disk_super, tree_root, fs_info,
+                                  BTRFS_INODE_MAP_OBJECTID, inode_root);
         BUG_ON(ret);
 
-        ret = find_and_setup_root(super, tree_root, fs_info,
-                                  BTRFS_FS_TREE_OBJECTID, root, fp);
+        ret = find_and_setup_root(disk_super, tree_root, fs_info,
+                                  BTRFS_FS_TREE_OBJECTID, root);
         BUG_ON(ret);
 
         root->commit_root = root->node;
-        root->node->count++;
+        get_bh(root->node);
         root->ref_cows = 1;
         root->fs_info->generation = root->root_key.offset + 1;
         return root;
@@ -336,8 +227,11 @@ struct btrfs_root *open_ctree_fd(int fp, struct btrfs_super_block *super)
 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
                       *root, struct btrfs_super_block *s)
 {
+        return 0;
+#if 0
         int ret;
-        btrfs_set_super_root(s, root->fs_info->tree_root->node->blocknr);
+        btrfs_set_super_root(s, root->fs_info->tree_root->node->b_blocknr);
+
         ret = pwrite(root->fs_info->fp, s, sizeof(*s),
                      BTRFS_SUPER_INFO_OFFSET);
         if (ret != sizeof(*s)) {
@@ -345,35 +239,38 @@ int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
                 return ret;
         }
         return 0;
+#endif
 }
 
 static int drop_cache(struct btrfs_root *root)
 {
+        return 0;
+#if 0
         while(!list_empty(&root->fs_info->cache)) {
-                struct btrfs_buffer *b = list_entry(root->fs_info->cache.next,
-                                                    struct btrfs_buffer,
+                struct buffer_head *b = list_entry(root->fs_info->cache.next,
+                                                    struct buffer_head,
                                                     cache);
                 list_del_init(&b->cache);
                 btrfs_block_release(root, b);
         }
         return 0;
+#endif
 }
-int close_ctree(struct btrfs_root *root, struct btrfs_super_block *s)
+
+int close_ctree(struct btrfs_root *root)
 {
         int ret;
         struct btrfs_trans_handle *trans;
 
         trans = root->fs_info->running_transaction;
-        btrfs_commit_transaction(trans, root, s);
+        btrfs_commit_transaction(trans, root, root->fs_info->disk_super);
         ret = commit_tree_roots(trans, root->fs_info);
         BUG_ON(ret);
         ret = __commit_transaction(trans, root);
         BUG_ON(ret);
-        write_ctree_super(trans, root, s);
+        write_ctree_super(trans, root, root->fs_info->disk_super);
         drop_cache(root);
-        BUG_ON(!list_empty(&root->fs_info->trans));
 
-        close(root->fs_info->fp);
         if (root->node)
                 btrfs_block_release(root, root->node);
         if (root->fs_info->extent_root->node)
@@ -386,29 +283,17 @@ int close_ctree(struct btrfs_root *root, struct btrfs_super_block *s)
                 btrfs_block_release(root->fs_info->tree_root,
                                     root->fs_info->tree_root->node);
         btrfs_block_release(root, root->commit_root);
-        free(root);
-        printf("on close %d blocks are allocated\n", allocated_blocks);
+        btrfs_block_release(root, root->fs_info->sb_buffer);
+        kfree(root->fs_info->extent_root);
+        kfree(root->fs_info->inode_root);
+        kfree(root->fs_info->tree_root);
+        kfree(root->fs_info);
+        kfree(root);
         return 0;
 }
 
-void btrfs_block_release(struct btrfs_root *root, struct btrfs_buffer *buf)
+void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
 {
-        buf->count--;
-        if (buf->count < 0)
-                BUG();
-        if (buf->count == 0) {
-                BUG_ON(!list_empty(&buf->cache));
-                BUG_ON(!list_empty(&buf->dirty));
-                if (!radix_tree_lookup(&root->fs_info->cache_radix,
-                                       buf->blocknr))
-                        BUG();
-                radix_tree_delete(&root->fs_info->cache_radix, buf->blocknr);
-                memset(buf, 0, sizeof(*buf));
-                free(buf);
-                BUG_ON(allocated_blocks == 0);
-                allocated_blocks--;
-                BUG_ON(root->fs_info->cache_size == 0);
-                root->fs_info->cache_size--;
-        }
+        brelse(buf);
 }