Btrfs: Dynamic chunk and block group allocation

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

1 files changed, 190 insertions, 18 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2cd957d6e8d8..15082b1087be 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -36,6 +36,10 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
                                  btrfs_root *extent_root);
 static int del_pending_extents(struct btrfs_trans_handle *trans, struct
                                btrfs_root *extent_root);
+int btrfs_make_block_group(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root, u64 bytes_used,
+                           u64 type, u64 chunk_tree, u64 chunk_objectid,
+                           u64 size);
 
 
 static int cache_block_group(struct btrfs_root *root,
@@ -168,16 +172,7 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
 
 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
 {
-        if ((bits & BLOCK_GROUP_DATA) &&
-            (cache->flags & BTRFS_BLOCK_GROUP_DATA))
-                return 1;
-        if ((bits & BLOCK_GROUP_METADATA) &&
-             (cache->flags & BTRFS_BLOCK_GROUP_METADATA))
-                return 1;
-        if ((bits & BLOCK_GROUP_SYSTEM) &&
-             (cache->flags & BTRFS_BLOCK_GROUP_SYSTEM))
-                return 1;
-        return 0;
+        return (cache->flags & bits);
 }
 
 static int noinline find_search_start(struct btrfs_root *root,
@@ -276,6 +271,18 @@ static u64 div_factor(u64 num, int factor)
         return num;
 }
 
+static int block_group_state_bits(u64 flags)
+{
+        int bits = 0;
+        if (flags & BTRFS_BLOCK_GROUP_DATA)
+                bits |= BLOCK_GROUP_DATA;
+        if (flags & BTRFS_BLOCK_GROUP_METADATA)
+                bits |= BLOCK_GROUP_METADATA;
+        if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
+                bits |= BLOCK_GROUP_SYSTEM;
+        return bits;
+}
+
 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
                                                  struct btrfs_block_group_cache
                                                  *hint, u64 search_start,
@@ -304,7 +311,7 @@ struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
         if (!owner)
                 factor = 8;
 
-        bit = data;
+        bit = block_group_state_bits(data);
 
         if (search_start && search_start < total_fs_bytes) {
                 struct btrfs_block_group_cache *shint;
@@ -358,10 +365,15 @@ again:
                         free_check = cache->key.offset;
                 else
                         free_check = div_factor(cache->key.offset, factor);
+
                 if (used + cache->pinned < free_check) {
                         found_group = cache;
                         goto found;
                 }
+                if (full_search) {
+                        printk("failed on cache %Lu used %Lu total %Lu\n",
+                               cache->key.objectid, used, cache->key.offset);
+                }
                 cond_resched();
         }
         if (!full_search) {
@@ -983,6 +995,58 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
         return werr;
 }
 
+static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
+                                                  u64 flags)
+{
+        struct list_head *head = &info->space_info;
+        struct list_head *cur;
+        struct btrfs_space_info *found;
+        list_for_each(cur, head) {
+                found = list_entry(cur, struct btrfs_space_info, list);
+                if (found->flags == flags)
+                        return found;
+        }
+        return NULL;
+
+}
+
+static int do_chunk_alloc(struct btrfs_trans_handle *trans,
+                          struct btrfs_root *extent_root, u64 alloc_bytes,
+                          u64 flags)
+{
+        struct btrfs_space_info *space_info;
+        u64 thresh;
+        u64 start;
+        u64 num_bytes;
+        int ret;
+
+        space_info = __find_space_info(extent_root->fs_info, flags);
+        BUG_ON(!space_info);
+
+        if (space_info->full)
+                return 0;
+
+        thresh = div_factor(space_info->total_bytes, 7);
+        if ((space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
+            thresh)
+                return 0;
+
+        ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
+        if (ret == -ENOSPC) {
+printk("space info full %Lu\n", flags);
+                space_info->full = 1;
+                return 0;
+        }
+
+        BUG_ON(ret);
+
+        ret = btrfs_make_block_group(trans, extent_root, 0, flags,
+                     extent_root->fs_info->chunk_root->root_key.objectid,
+                     start, num_bytes);
+        BUG_ON(ret);
+        return 0;
+}
+
 static int update_block_group(struct btrfs_trans_handle *trans,
                               struct btrfs_root *root,
                               u64 bytenr, u64 num_bytes, int alloc,
@@ -1012,8 +1076,10 @@ static int update_block_group(struct btrfs_trans_handle *trans,
                 num_bytes = min(total, cache->key.offset - byte_in_group);
                 if (alloc) {
                         old_val += num_bytes;
+                        cache->space_info->bytes_used += num_bytes;
                 } else {
                         old_val -= num_bytes;
+                        cache->space_info->bytes_used -= num_bytes;
                         if (mark_free) {
                                 set_extent_dirty(&info->free_space_cache,
                                                  bytenr, bytenr + num_bytes - 1,
@@ -1026,6 +1092,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
         }
         return 0;
 }
+
 static int update_pinned_extents(struct btrfs_root *root,
                                 u64 bytenr, u64 num, int pin)
 {
@@ -1047,9 +1114,11 @@ static int update_pinned_extents(struct btrfs_root *root,
                           (bytenr - cache->key.objectid));
                 if (pin) {
                         cache->pinned += len;
+                        cache->space_info->bytes_pinned += len;
                         fs_info->total_pinned += len;
                 } else {
                         cache->pinned -= len;
+                        cache->space_info->bytes_pinned -= len;
                         fs_info->total_pinned -= len;
                 }
                 bytenr += len;
@@ -1472,7 +1541,7 @@ check_failed:
                 goto new_group;
         }
 
-        if (!(data & BLOCK_GROUP_DATA)) {
+        if (!(data & BTRFS_BLOCK_GROUP_DATA)) {
                 block_group = btrfs_lookup_block_group(info, ins->objectid);
                 if (block_group)
                         trans->block_group = block_group;
@@ -1532,12 +1601,25 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
         struct btrfs_path *path;
         struct btrfs_key keys[2];
 
-        if (data)
-                data = BLOCK_GROUP_DATA;
-        else if (root == root->fs_info->chunk_root)
-                data = BLOCK_GROUP_SYSTEM;
-        else
-                data = BLOCK_GROUP_METADATA;
+        if (data) {
+                data = BTRFS_BLOCK_GROUP_DATA;
+        } else if (root == root->fs_info->chunk_root) {
+                data = BTRFS_BLOCK_GROUP_SYSTEM;
+        } else {
+                data = BTRFS_BLOCK_GROUP_METADATA;
+        }
+
+        if (root->ref_cows) {
+                if (data != BTRFS_BLOCK_GROUP_METADATA) {
+                        ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+                                             num_bytes,
+                                             BTRFS_BLOCK_GROUP_METADATA);
+                        BUG_ON(ret);
+                }
+                ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+                                     num_bytes, data);
+                BUG_ON(ret);
+        }
 
         new_hint = max(hint_byte, root->fs_info->alloc_start);
         if (new_hint < btrfs_super_total_bytes(&info->super_copy))
@@ -2490,6 +2572,34 @@ error:
         return ret;
 }
 
+static int update_space_info(struct btrfs_fs_info *info, u64 flags,
+                             u64 total_bytes, u64 bytes_used,
+                             struct btrfs_space_info **space_info)
+{
+        struct btrfs_space_info *found;
+
+        found = __find_space_info(info, flags);
+        if (found) {
+                found->total_bytes += total_bytes;
+                found->bytes_used += bytes_used;
+                WARN_ON(found->total_bytes < found->bytes_used);
+                *space_info = found;
+                return 0;
+        }
+        found = kmalloc(sizeof(*found), GFP_NOFS);
+        if (!found)
+                return -ENOMEM;
+
+        list_add(&found->list, &info->space_info);
+        found->flags = flags;
+        found->total_bytes = total_bytes;
+        found->bytes_used = bytes_used;
+        found->bytes_pinned = 0;
+        found->full = 0;
+        *space_info = found;
+        return 0;
+}
+
 int btrfs_read_block_groups(struct btrfs_root *root)
 {
         struct btrfs_path *path;
@@ -2497,6 +2607,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
         int bit;
         struct btrfs_block_group_cache *cache;
         struct btrfs_fs_info *info = root->fs_info;
+        struct btrfs_space_info *space_info;
         struct extent_io_tree *block_group_cache;
         struct btrfs_key key;
         struct btrfs_key found_key;
@@ -2547,6 +2658,12 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                         bit = BLOCK_GROUP_METADATA;
                 }
 
+                ret = update_space_info(info, cache->flags, found_key.offset,
+                                        btrfs_block_group_used(&cache->item),
+                                        &space_info);
+                BUG_ON(ret);
+                cache->space_info = space_info;
+
                 /* use EXTENT_LOCKED to prevent merging */
                 set_extent_bits(block_group_cache, found_key.objectid,
                                 found_key.objectid + found_key.offset - 1,
@@ -2563,3 +2680,58 @@ error:
         btrfs_free_path(path);
         return ret;
 }
+
+int btrfs_make_block_group(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root, u64 bytes_used,
+                           u64 type, u64 chunk_tree, u64 chunk_objectid,
+                           u64 size)
+{
+        int ret;
+        int bit = 0;
+        struct btrfs_root *extent_root;
+        struct btrfs_block_group_cache *cache;
+        struct extent_io_tree *block_group_cache;
+
+        extent_root = root->fs_info->extent_root;
+        block_group_cache = &root->fs_info->block_group_cache;
+
+        cache = kmalloc(sizeof(*cache), GFP_NOFS);
+        BUG_ON(!cache);
+        cache->key.objectid = chunk_objectid;
+        cache->key.offset = size;
+        cache->cached = 0;
+        cache->pinned = 0;
+        btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
+        memset(&cache->item, 0, sizeof(cache->item));
+        btrfs_set_block_group_used(&cache->item, bytes_used);
+        btrfs_set_block_group_chunk_tree(&cache->item, chunk_tree);
+        btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
+        cache->flags = type;
+        btrfs_set_block_group_flags(&cache->item, type);
+
+        ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
+                                &cache->space_info);
+        BUG_ON(ret);
+
+        if (type & BTRFS_BLOCK_GROUP_DATA) {
+                bit = BLOCK_GROUP_DATA;
+        } else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
+                bit = BLOCK_GROUP_SYSTEM;
+        } else if (type & BTRFS_BLOCK_GROUP_METADATA) {
+                bit = BLOCK_GROUP_METADATA;
+        }
+        set_extent_bits(block_group_cache, chunk_objectid,
+                        chunk_objectid + size - 1,
+                        bit | EXTENT_LOCKED, GFP_NOFS);
+        set_state_private(block_group_cache, chunk_objectid,
+                          (unsigned long)cache);
+
+        ret = btrfs_insert_item(trans, extent_root, &cache->key, &cache->item,
+                                sizeof(cache->item));
+        BUG_ON(ret);
+
+        finish_current_insert(trans, extent_root);
+        ret = del_pending_extents(trans, extent_root);
+        BUG_ON(ret);
+        return 0;
+}