Btrfs: dirindex optimizations

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

5 files changed, 50 insertions, 17 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 794f7e4f1c07..6d40758b893f 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -239,6 +239,7 @@ struct btrfs_fs_info {
         struct radix_tree_root pinned_radix;
         u64 last_inode_alloc;
         u64 generation;
+        u64 highest_inode;
         struct btrfs_transaction *running_transaction;
         struct btrfs_super_block *disk_super;
         struct buffer_head *sb_buffer;
@@ -970,6 +971,8 @@ int btrfs_insert_inode_map(struct btrfs_trans_handle *trans,
 int btrfs_lookup_inode_map(struct btrfs_trans_handle *trans,
                            struct btrfs_root *root, struct btrfs_path *path,
                            u64 objectid, int mod);
+int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
+
 /* inode-item.c */
 int btrfs_insert_inode(struct btrfs_trans_handle *trans, struct btrfs_root
                        *root, u64 objectid, struct btrfs_inode_item
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index b1629a5d73c8..0ee9945fb1b0 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -92,6 +92,7 @@ int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
         int cow = mod != 0;
         struct btrfs_disk_key *found_key;
         struct btrfs_leaf *leaf;
+        u32 overflow;
 
         key.objectid = dir;
         key.flags = 0;
@@ -119,8 +120,10 @@ int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
                 if (btrfs_match_dir_item_name(root, path, name, name_len))
                         return 0;
 
-                if (btrfs_disk_key_overflow(found_key) == 0)
+                overflow = btrfs_disk_key_overflow(found_key);
+                if (overflow == 0)
                         return 1;
+                btrfs_set_key_overflow(&key, overflow - 1);
                 btrfs_release_path(root, path);
         }
         return 1;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index de9ee3aa0aad..5230554380d1 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -311,6 +311,7 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         fs_info->extent_root = extent_root;
         fs_info->inode_root = inode_root;
         fs_info->last_inode_alloc = 0;
+        fs_info->highest_inode = 0;
         fs_info->sb = sb;
         fs_info->btree_inode = new_inode(sb);
         fs_info->btree_inode->i_ino = 1;
@@ -360,12 +361,15 @@ printk("failed2\n");
 
         ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
                                   BTRFS_FS_TREE_OBJECTID, root);
-        mutex_unlock(&fs_info->fs_mutex);
         BUG_ON(ret);
         root->commit_root = root->node;
         get_bh(root->node);
         root->ref_cows = 1;
         root->fs_info->generation = root->root_key.offset + 1;
+        ret = btrfs_find_highest_inode(root, &root->fs_info->last_inode_alloc);
+        if (ret == 0)
+                fs_info->highest_inode = fs_info->last_inode_alloc;
+        mutex_unlock(&fs_info->fs_mutex);
         return root;
 }
 
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 329edb42897e..f665221409ac 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -3,6 +3,37 @@
 #include "disk-io.h"
 #include "transaction.h"
 
+int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid)
+{
+        struct btrfs_path *path;
+        int ret;
+        struct btrfs_leaf *l;
+        struct btrfs_root *root = fs_root->fs_info->inode_root;
+        struct btrfs_key search_key;
+        int slot;
+
+        path = btrfs_alloc_path();
+        BUG_ON(!path);
+
+        search_key.objectid = (u64)-1;
+        search_key.offset = (u64)-1;
+        ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
+        if (ret < 0)
+                goto error;
+        BUG_ON(ret == 0);
+        if (path->slots[0] > 0) {
+                slot = path->slots[0] - 1;
+                l = btrfs_buffer_leaf(path->nodes[0]);
+                *objectid = btrfs_disk_key_objectid(&l->items[slot].key);
+        } else {
+                *objectid = BTRFS_FIRST_FREE_OBJECTID;
+        }
+        ret = 0;
+error:
+        btrfs_free_path(path);
+        return ret;
+}
+
 /*
  * walks the btree of allocated inodes and find a hole.
  */
@@ -28,21 +59,6 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
         btrfs_set_key_type(&search_key, BTRFS_INODE_MAP_ITEM_KEY);
 
         search_start = fs_root->fs_info->last_inode_alloc;
-        if (search_start == 0) {
-                struct btrfs_disk_key *last_key;
-                btrfs_init_path(path);
-                search_key.objectid = (u64)-1;
-                search_key.offset = (u64)-1;
-                ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0);
-                if (ret < 0)
-                        goto error;
-                BUG_ON(ret == 0);
-                if (path->slots[0] > 0)
-                        path->slots[0]--;
-                l = btrfs_buffer_leaf(path->nodes[0]);
-                last_key = &l->items[path->slots[0]].key;
-                search_start = btrfs_disk_key_objectid(last_key);
-        }
         search_start = max(search_start, BTRFS_FIRST_FREE_OBJECTID);
         search_key.objectid = search_start;
         search_key.offset = 0;
@@ -129,6 +145,8 @@ int btrfs_insert_inode_map(struct btrfs_trans_handle *trans,
                                     path->slots[0], struct btrfs_inode_map_item);
         btrfs_cpu_key_to_disk(&inode_item->key, location);
         btrfs_mark_buffer_dirty(path->nodes[0]);
+        if (objectid > fs_root->fs_info->highest_inode)
+                fs_root->fs_info->highest_inode = objectid;
 out:
         btrfs_release_path(inode_root, path);
         btrfs_free_path(path);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 4fd2b168b2c4..d4ee78046b86 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -482,6 +482,11 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
                 item = leaf->items + slot;
                 if (btrfs_disk_key_objectid(&item->key) != key.objectid)
                         break;
+                if (btrfs_disk_key_offset(&item->key) >
+                    root->fs_info->highest_inode) {
+printk("stopping at highest inode %Lu\n", root->fs_info->highest_inode);
+                        break;
+                }
                 if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_INDEX_KEY)
                         continue;
                 if (btrfs_disk_key_offset(&item->key) < filp->f_pos)