Btrfs: Dynamic chunk and block group allocation

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

6 files changed, 263 insertions, 57 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 1453d995fef6..a877105f5c47 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -431,9 +431,19 @@ struct btrfs_block_group_item {
         __le64 flags;
 } __attribute__ ((__packed__));
 
+struct btrfs_space_info {
+        u64 flags;
+        u64 total_bytes;
+        u64 bytes_used;
+        u64 bytes_pinned;
+        int full;
+        struct list_head list;
+};
+
 struct btrfs_block_group_cache {
         struct btrfs_key key;
         struct btrfs_block_group_item item;
+        struct btrfs_space_info *space_info;
         u64 pinned;
         u64 flags;
         int cached;
@@ -490,7 +500,7 @@ struct btrfs_fs_info {
         struct list_head dirty_cowonly_roots;
 
         struct list_head devices;
-        struct list_head *last_device;
+        struct list_head space_info;
         spinlock_t delalloc_lock;
         spinlock_t new_trans_lock;
         u64 delalloc_bytes;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 8e37fa120cc8..2a239ae49f78 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -700,8 +700,8 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         fs_info->dev_root = dev_root;
         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
         INIT_LIST_HEAD(&fs_info->devices);
+        INIT_LIST_HEAD(&fs_info->space_info);
         btrfs_mapping_init(&fs_info->mapping_tree);
-        fs_info->last_device = &fs_info->devices;
         fs_info->sb = sb;
         fs_info->throttles = 0;
         fs_info->mount_opt = 0;
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;
+}
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 17063cd2cb73..109576b57f69 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1527,6 +1527,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 {
         struct inode *inode;
         struct btrfs_inode_item *inode_item;
+        struct btrfs_block_group_cache *new_inode_group;
         struct btrfs_key *location;
         struct btrfs_path *path;
         struct btrfs_inode_ref *ref;
@@ -1553,9 +1554,13 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
                 owner = 0;
         else
                 owner = 1;
-        group = btrfs_find_block_group(root, group, 0,
+        new_inode_group = btrfs_find_block_group(root, group, 0,
                                        BTRFS_BLOCK_GROUP_METADATA, owner);
-        BTRFS_I(inode)->block_group = group;
+        if (!new_inode_group) {
+                printk("find_block group failed\n");
+                new_inode_group = group;
+        }
+        BTRFS_I(inode)->block_group = new_inode_group;
         BTRFS_I(inode)->flags = 0;
 
         key[0].objectid = objectid;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 90a8d45dc6d7..a52a13f365d6 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -131,7 +131,7 @@ check_pending:
         btrfs_release_path(root, path);
         BUG_ON(*start < search_start);
 
-        if (*start + num_bytes >= search_end) {
+        if (*start + num_bytes > search_end) {
                 ret = -ENOSPC;
                 goto error;
         }
@@ -159,8 +159,9 @@ int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
                 return -ENOMEM;
 
         ret = find_free_dev_extent(trans, device, path, num_bytes, start);
-        if (ret)
+        if (ret) {
                 goto err;
+        }
 
         key.objectid = device->devid;
         key.offset = *start;
@@ -214,22 +215,6 @@ error:
         return ret;
 }
 
-static struct btrfs_device *next_device(struct list_head *head,
-                                        struct list_head *last)
-{
-        struct list_head *next = last->next;
-        struct btrfs_device *dev;
-
-        if (list_empty(head))
-                return NULL;
-
-        if (next == head)
-                next = next->next;
-
-        dev = list_entry(next, struct btrfs_device, dev_list);
-        return dev;
-}
-
 static int find_next_devid(struct btrfs_root *root, struct btrfs_path *path,
                            u64 *objectid)
 {
@@ -397,31 +382,63 @@ int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
 
 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                       struct btrfs_root *extent_root, u64 *start,
-                      u64 *num_bytes, u32 type)
+                      u64 *num_bytes, u64 type)
 {
         u64 dev_offset;
         struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root;
         struct btrfs_stripe *stripes;
         struct btrfs_device *device = NULL;
         struct btrfs_chunk *chunk;
+        struct list_head private_devs;
         struct list_head *dev_list = &extent_root->fs_info->devices;
-        struct list_head *last_dev = extent_root->fs_info->last_device;
+        struct list_head *cur;
         struct extent_map_tree *em_tree;
         struct map_lookup *map;
         struct extent_map *em;
         u64 physical;
         u64 calc_size = 1024 * 1024 * 1024;
-        int num_stripes;
+        u64 avail;
+        u64 max_avail = 0;
+        int num_stripes = 1;
+        int looped = 0;
         int ret;
-        int index = 0;
+        int index;
         struct btrfs_key key;
 
+        if (list_empty(dev_list))
+                return -ENOSPC;
+again:
+        INIT_LIST_HEAD(&private_devs);
+        cur = dev_list->next;
+        index = 0;
+        /* build a private list of devices we will allocate from */
+        while(index < num_stripes) {
+                device = list_entry(cur, struct btrfs_device, dev_list);
+                avail = device->total_bytes - device->bytes_used;
+                cur = cur->next;
+                if (avail > max_avail)
+                        max_avail = avail;
+                if (avail >= calc_size) {
+                        list_move_tail(&device->dev_list, &private_devs);
+                        index++;
+                }
+                if (cur == dev_list)
+                        break;
+        }
+        if (index < num_stripes) {
+                list_splice(&private_devs, dev_list);
+                if (!looped && max_avail > 0) {
+                        looped = 1;
+                        calc_size = max_avail;
+                        goto again;
+                }
+                return -ENOSPC;
+        }
 
         ret = find_next_chunk(chunk_root, &key.objectid);
         if (ret)
                 return ret;
 
-        num_stripes = 1;
         chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS);
         if (!chunk)
                 return -ENOMEM;
@@ -429,11 +446,12 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
         stripes = &chunk->stripe;
 
         *num_bytes = calc_size;
+        index = 0;
         while(index < num_stripes) {
-                device = next_device(dev_list, last_dev);
-                BUG_ON(!device);
-                last_dev = &device->dev_list;
-                extent_root->fs_info->last_device = last_dev;
+                BUG_ON(list_empty(&private_devs));
+                cur = private_devs.next;
+                device = list_entry(cur, struct btrfs_device, dev_list);
+                list_move_tail(&device->dev_list, dev_list);
 
                 ret = btrfs_alloc_dev_extent(trans, device,
                                              key.objectid,
@@ -449,6 +467,7 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                 physical = dev_offset;
                 index++;
         }
+        BUG_ON(!list_empty(&private_devs));
 
         /* key.objectid was set above */
         key.offset = *num_bytes;
@@ -692,17 +711,17 @@ static int read_one_dev(struct btrfs_root *root, struct btrfs_key *key,
         int ret;
 
         devid = btrfs_device_id(leaf, dev_item);
-        if (btrfs_find_device(root, devid))
-                return 0;
-
-        device = kmalloc(sizeof(*device), GFP_NOFS);
-        if (!device)
-                return -ENOMEM;
+        device = btrfs_find_device(root, devid);
+        if (!device) {
+                device = kmalloc(sizeof(*device), GFP_NOFS);
+                if (!device)
+                        return -ENOMEM;
+                list_add(&device->dev_list, &root->fs_info->devices);
+        }
 
         fill_device_from_item(leaf, dev_item, device);
         device->dev_root = root->fs_info->dev_root;
         device->bdev = root->fs_info->sb->s_bdev;
-        list_add(&device->dev_list, &root->fs_info->devices);
         memcpy(&device->dev_key, key, sizeof(*key));
         ret = 0;
 #if 0
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 4a47dcb00a73..4ab9891878a8 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -71,7 +71,7 @@ int btrfs_read_sys_array(struct btrfs_root *root);
 int btrfs_read_chunk_tree(struct btrfs_root *root);
 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                       struct btrfs_root *extent_root, u64 *start,
-                      u64 *num_bytes, u32 type);
+                      u64 *num_bytes, u64 type);
 void btrfs_mapping_init(struct btrfs_mapping_tree *tree);
 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree);
 int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio);