Btrfs: start of block group code

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

6 files changed, 252 insertions, 32 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 26d0cdd46f49..419917279e65 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -239,6 +239,19 @@ struct btrfs_device_item {
         __le64 device_id;
 } __attribute__ ((__packed__));
 
+/* tag for the radix tree of block groups in ram */
+#define BTRFS_BLOCK_GROUP_DIRTY 0
+#define BTRFS_BLOCK_GROUP_HINTS 8
+#define BTRFS_BLOCK_GROUP_SIZE (256 * 1024 * 1024)
+struct btrfs_block_group_item {
+        __le64 used;
+} __attribute__ ((__packed__));
+
+struct btrfs_block_group_cache {
+        struct btrfs_key key;
+        struct btrfs_block_group_item item;
+};
+
 struct crypto_hash;
 struct btrfs_fs_info {
         struct btrfs_root *extent_root;
@@ -249,6 +262,7 @@ struct btrfs_fs_info {
         struct radix_tree_root pending_del_radix;
         struct radix_tree_root pinned_radix;
         struct radix_tree_root dev_radix;
+        struct radix_tree_root block_group_radix;
 
         u64 extent_tree_insert[BTRFS_MAX_LEVEL * 3];
         int extent_tree_insert_nr;
@@ -301,49 +315,67 @@ struct btrfs_root {
  * info about object characteristics.  There is one for every file and dir in
  * the FS
  */
-#define BTRFS_INODE_ITEM_KEY    1
+#define BTRFS_INODE_ITEM_KEY            1
+
+/* reserve 2-15 close to the inode for later flexibility */
 
 /*
  * dir items are the name -> inode pointers in a directory.  There is one
  * for every name in a directory.
  */
-#define BTRFS_DIR_ITEM_KEY      2
-#define BTRFS_DIR_INDEX_KEY     3
+#define BTRFS_DIR_ITEM_KEY      16
+#define BTRFS_DIR_INDEX_KEY     17
 /*
- * inline data is file data that fits in the btree.
+ * extent data is for file data
  */
-#define BTRFS_INLINE_DATA_KEY   4
-/*
- * extent data is for data that can't fit in the btree.  It points to
- * a (hopefully) huge chunk of disk
- */
-#define BTRFS_EXTENT_DATA_KEY   5
+#define BTRFS_EXTENT_DATA_KEY   18
 /*
  * csum items have the checksums for data in the extents
  */
-#define BTRFS_CSUM_ITEM_KEY     6
+#define BTRFS_CSUM_ITEM_KEY     19
+
+/* reserve 20-31 for other file stuff */
 
 /*
  * root items point to tree roots.  There are typically in the root
  * tree used by the super block to find all the other trees
  */
-#define BTRFS_ROOT_ITEM_KEY     7
+#define BTRFS_ROOT_ITEM_KEY     32
 /*
  * extent items are in the extent map tree.  These record which blocks
  * are used, and how many references there are to each block
  */
-#define BTRFS_EXTENT_ITEM_KEY   8
+#define BTRFS_EXTENT_ITEM_KEY   33
+
+/*
+ * block groups give us hints into the extent allocation trees.  Which
+ * blocks are free etc etc
+ */
+#define BTRFS_BLOCK_GROUP_ITEM_KEY 34
 
 /*
  * dev items list the devices that make up the FS
  */
-#define BTRFS_DEV_ITEM_KEY      9
+#define BTRFS_DEV_ITEM_KEY      35
 
 /*
  * string items are for debugging.  They just store a short string of
  * data in the FS
  */
-#define BTRFS_STRING_ITEM_KEY   10
+#define BTRFS_STRING_ITEM_KEY   253
+
+
+static inline u64 btrfs_block_group_used(struct btrfs_block_group_item *bi)
+{
+        return le64_to_cpu(bi->used);
+}
+
+static inline void btrfs_set_block_group_used(struct
+                                                   btrfs_block_group_item *bi,
+                                                   u64 val)
+{
+        bi->used = cpu_to_le64(val);
+}
 
 static inline u64 btrfs_inode_generation(struct btrfs_inode_item *i)
 {
@@ -1037,6 +1069,10 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
                                 u64 blocknr, u64 num_blocks);
+int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
+                                    struct btrfs_root *root);
+int btrfs_free_block_groups(struct btrfs_fs_info *info);
+int btrfs_read_block_groups(struct btrfs_root *root);
 /* ctree.c */
 int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
                       *root, struct btrfs_path *path, u32 data_size);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 956727f015a5..1c27eb645510 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -529,6 +529,7 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         init_bit_radix(&fs_info->pending_del_radix);
         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
         INIT_RADIX_TREE(&fs_info->dev_radix, GFP_NOFS);
+        INIT_RADIX_TREE(&fs_info->block_group_radix, GFP_KERNEL);
         INIT_LIST_HEAD(&fs_info->trans_list);
         sb_set_blocksize(sb, 4096);
         fs_info->running_transaction = NULL;
@@ -613,6 +614,8 @@ struct btrfs_root *open_ctree(struct super_block *sb)
                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
         BUG_ON(ret);
 
+        btrfs_read_block_groups(extent_root);
+
         fs_info->generation = btrfs_super_generation(disk_super) + 1;
         memset(&fs_info->kobj, 0, sizeof(fs_info->kobj));
         kobj_set_kset_s(fs_info, btrfs_subsys);
@@ -741,6 +744,7 @@ int close_ctree(struct btrfs_root *root)
         iput(fs_info->btree_inode);
 
         free_dev_radix(fs_info);
+        btrfs_free_block_groups(root->fs_info);
         del_fs_roots(fs_info);
         kfree(fs_info->extent_root);
         kfree(fs_info->tree_root);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index e6fe3fd38819..0bb4fc83cfd6 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -127,6 +127,105 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
         return 0;
 }
 
+static int write_one_cache_group(struct btrfs_trans_handle *trans,
+                                 struct btrfs_root *root,
+                                 struct btrfs_path *path,
+                                 struct btrfs_block_group_cache *cache)
+{
+        int ret;
+        int pending_ret;
+        struct btrfs_root *extent_root = root->fs_info->extent_root;
+        struct btrfs_block_group_item *bi;
+        struct btrfs_key ins;
+
+        find_free_extent(trans, extent_root, 0, 0, (u64)-1, &ins);
+        ret = btrfs_search_slot(trans, extent_root, &cache->key, path, 0, 1);
+        BUG_ON(ret);
+        bi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
+                            struct btrfs_block_group_item);
+        memcpy(bi, &cache->item, sizeof(*bi));
+        mark_buffer_dirty(path->nodes[0]);
+        btrfs_release_path(extent_root, path);
+
+        finish_current_insert(trans, extent_root);
+        pending_ret = del_pending_extents(trans, extent_root);
+        if (ret)
+                return ret;
+        if (pending_ret)
+                return pending_ret;
+        return 0;
+
+}
+
+int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
+                                    struct btrfs_root *root)
+{
+        struct btrfs_block_group_cache *cache[8];
+        int ret;
+        int err = 0;
+        int werr = 0;
+        struct radix_tree_root *radix = &root->fs_info->block_group_radix;
+        int i;
+        struct btrfs_path *path;
+
+        path = btrfs_alloc_path();
+        if (!path)
+                return -ENOMEM;
+
+        while(1) {
+                ret = radix_tree_gang_lookup_tag(radix, (void **)cache,
+                                                 0, ARRAY_SIZE(cache),
+                                                 BTRFS_BLOCK_GROUP_DIRTY);
+                if (!ret)
+                        break;
+                for (i = 0; i < ret; i++) {
+                        radix_tree_tag_clear(radix, cache[i]->key.objectid +
+                                             cache[i]->key.offset - 1,
+                                             BTRFS_BLOCK_GROUP_DIRTY);
+                        err = write_one_cache_group(trans, root,
+                                                    path, cache[i]);
+                        if (err)
+                                werr = err;
+                }
+        }
+        btrfs_free_path(path);
+        return werr;
+}
+
+static int update_block_group(struct btrfs_trans_handle *trans,
+                              struct btrfs_root *root,
+                              u64 blocknr, u64 num, int alloc)
+{
+        struct btrfs_block_group_cache *cache;
+        struct btrfs_fs_info *info = root->fs_info;
+        u64 total = num;
+        u64 old_val;
+        u64 block_in_group;
+        int ret;
+        while(total) {
+                ret = radix_tree_gang_lookup(&info->block_group_radix,
+                                             (void **)&cache, blocknr, 1);
+                if (!ret)
+                        return -1;
+                block_in_group = blocknr - cache->key.objectid;
+                WARN_ON(block_in_group > cache->key.offset);
+                radix_tree_tag_set(&info->block_group_radix,
+                                   cache->key.objectid + cache->key.offset - 1,
+                                   BTRFS_BLOCK_GROUP_DIRTY);
+
+                old_val = btrfs_block_group_used(&cache->item);
+                num = min(total, cache->key.offset - block_in_group);
+                total -= num;
+                blocknr += num;
+                if (alloc)
+                        old_val += num;
+                else
+                        old_val -= num;
+                btrfs_set_block_group_used(&cache->item, old_val);
+        }
+        return 0;
+}
+
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
                                btrfs_root *root)
 {
@@ -264,6 +363,8 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
                 ret = btrfs_del_item(trans, extent_root, path);
                 if (ret)
                         BUG();
+                ret = update_block_group(trans, root, blocknr, num_blocks, 0);
+                BUG_ON(ret);
         }
         btrfs_release_path(extent_root, path);
         btrfs_free_path(path);
@@ -365,21 +466,6 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
                 num_blocks = 1;
                 total_needed = min(level + 2, BTRFS_MAX_LEVEL) * 3;
         }
-        if (info->last_insert.objectid == 0 && search_end == (u64)-1) {
-                struct btrfs_disk_key *last_key;
-                btrfs_init_path(path);
-                ins->objectid = (u64)-1;
-                ins->offset = (u64)-1;
-                ret = btrfs_search_slot(trans, root, ins, 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);
-        }
         if (info->last_insert.objectid > search_start)
                 search_start = info->last_insert.objectid;
 
@@ -420,6 +506,8 @@ check_failed:
                         goto check_pending;
                 }
                 btrfs_disk_key_to_cpu(&key, &l->items[slot].key);
+                if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
+                        goto next;
                 if (key.objectid >= search_start) {
                         if (start_found) {
                                 if (last_block < search_start)
@@ -434,6 +522,7 @@ check_failed:
                 }
                 start_found = 1;
                 last_block = key.objectid + key.offset;
+next:
                 path->slots[0]++;
         }
         // FIXME -ENOSPC
@@ -498,7 +587,6 @@ error:
         btrfs_free_path(path);
         return ret;
 }
-
 /*
  * finds a free extent and does all the dirty work required for allocation
  * returns the key for the extent through ins, and a tree buffer for
@@ -532,6 +620,9 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
                 ins->objectid = info->extent_tree_prealloc[nr];
                 info->extent_tree_insert[info->extent_tree_insert_nr++] =
                         ins->objectid;
+                ret = update_block_group(trans, root,
+                                         ins->objectid, ins->offset, 1);
+                BUG_ON(ret);
                 return 0;
         }
         /* do the real allocation */
@@ -558,6 +649,7 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
                 return ret;
         if (pending_ret)
                 return pending_ret;
+        ret = update_block_group(trans, root, ins->objectid, ins->offset, 1);
         return 0;
 }
 
@@ -578,6 +670,7 @@ struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
                 BUG();
                 return NULL;
         }
+        BUG_ON(ret);
         buf = btrfs_find_create_tree_block(root, ins.objectid);
         set_buffer_uptodate(buf);
         return buf;
@@ -758,3 +851,82 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
         btrfs_free_path(path);
         return ret;
 }
+
+int btrfs_free_block_groups(struct btrfs_fs_info *info)
+{
+        int ret;
+        struct btrfs_block_group_cache *cache[8];
+        int i;
+
+        while(1) {
+                ret = radix_tree_gang_lookup(&info->block_group_radix,
+                                             (void **)cache, 0,
+                                             ARRAY_SIZE(cache));
+                if (!ret)
+                        break;
+                for (i = 0; i < ret; i++) {
+                        radix_tree_delete(&info->block_group_radix,
+                                          cache[i]->key.objectid +
+                                          cache[i]->key.offset - 1);
+                        kfree(cache[i]);
+                }
+        }
+        return 0;
+}
+
+int btrfs_read_block_groups(struct btrfs_root *root)
+{
+        struct btrfs_path *path;
+        int ret;
+        int err = 0;
+        struct btrfs_block_group_item *bi;
+        struct btrfs_block_group_cache *cache;
+        struct btrfs_key key;
+        struct btrfs_key found_key;
+        struct btrfs_leaf *leaf;
+        u64 group_size_blocks = BTRFS_BLOCK_GROUP_SIZE / root->blocksize;
+
+        root = root->fs_info->extent_root;
+        key.objectid = 0;
+        key.offset = group_size_blocks;
+        key.flags = 0;
+        btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
+
+        path = btrfs_alloc_path();
+        if (!path)
+                return -ENOMEM;
+
+        while(1) {
+                ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
+                                        &key, path, 0, 0);
+                if (ret != 0) {
+                        err = ret;
+                        break;
+                }
+                leaf = btrfs_buffer_leaf(path->nodes[0]);
+                btrfs_disk_key_to_cpu(&found_key,
+                                      &leaf->items[path->slots[0]].key);
+                cache = kmalloc(sizeof(*cache), GFP_NOFS);
+                if (!cache) {
+                        err = -1;
+                        break;
+                }
+                bi = btrfs_item_ptr(leaf, path->slots[0],
+                                    struct btrfs_block_group_item);
+                memcpy(&cache->item, bi, sizeof(*bi));
+                memcpy(&cache->key, &found_key, sizeof(found_key));
+                key.objectid = found_key.objectid + found_key.offset;
+                btrfs_release_path(root, path);
+                ret = radix_tree_insert(&root->fs_info->block_group_radix,
+                                        found_key.objectid +
+                                        found_key.offset - 1,
+                                        (void *)cache);
+                BUG_ON(ret);
+                if (key.objectid >=
+                    btrfs_super_total_blocks(root->fs_info->disk_super))
+                        break;
+        }
+
+        btrfs_free_path(path);
+        return 0;
+}
diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c
index 1e7038b070ae..2f95fc67a036 100644
--- a/fs/btrfs/print-tree.c
+++ b/fs/btrfs/print-tree.c
@@ -11,6 +11,7 @@ void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l)
         struct btrfs_root_item *ri;
         struct btrfs_dir_item *di;
         struct btrfs_inode_item *ii;
+        struct btrfs_block_group_item *bi;
         u32 type;
 
         printk("leaf %Lu total ptrs %d free space %d\n",
@@ -53,6 +54,12 @@ void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l)
                         printk("\t\textent data refs %u\n",
                                 btrfs_extent_refs(ei));
                         break;
+                case BTRFS_BLOCK_GROUP_ITEM_KEY:
+                        bi = btrfs_item_ptr(l, i,
+                                            struct btrfs_block_group_item);
+                        printk("\t\tblock group used %Lu\n",
+                               btrfs_block_group_used(bi));
+                        break;
                 case BTRFS_STRING_ITEM_KEY:
                         printk("\t\titem data %.*s\n", btrfs_item_size(item),
                                 btrfs_leaf_data(l) + btrfs_item_offset(item));
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 5bbccbc7e3cc..edcebf79b04a 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -377,7 +377,6 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                 if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
                         break;
                 if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
-                    btrfs_disk_key_type(found_key) != BTRFS_INLINE_DATA_KEY &&
                     btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
                         break;
                 if (btrfs_disk_key_offset(found_key) < inode->i_size)
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 078cb9cbf9dd..8a2545f6a5b6 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -125,6 +125,7 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
                 btrfs_set_super_device_root(fs_info->disk_super,
                                             bh_blocknr(dev_root->node));
         }
+        btrfs_write_dirty_block_groups(trans, extent_root);
         while(1) {
                 old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
                 if (old_extent_block == bh_blocknr(extent_root->node))
@@ -135,6 +136,7 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
                                         &extent_root->root_key,
                                         &extent_root->root_item);
                 BUG_ON(ret);
+                btrfs_write_dirty_block_groups(trans, extent_root);
         }
         return 0;
 }