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-rw-r--r--fs/btrfs/ctree.h54
-rw-r--r--fs/btrfs/disk-io.c5
-rw-r--r--fs/btrfs/extent-tree.c181
-rw-r--r--fs/btrfs/free-space-cache.c297
-rw-r--r--fs/btrfs/free-space-cache.h44
-rw-r--r--fs/btrfs/transaction.c2
6 files changed, 509 insertions, 74 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index aaa049b8e134..b82931f97ef3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -633,11 +633,29 @@ struct btrfs_space_info {
struct rw_semaphore groups_sem;
};
-struct btrfs_free_space {
- struct rb_node bytes_index;
- struct rb_node offset_index;
- u64 offset;
- u64 bytes;
+/*
+ * free clusters are used to claim free space in relatively large chunks,
+ * allowing us to do less seeky writes. They are used for all metadata
+ * allocations and data allocations in ssd mode.
+ */
+struct btrfs_free_cluster {
+ spinlock_t lock;
+ spinlock_t refill_lock;
+ struct rb_root root;
+
+ /* largest extent in this cluster */
+ u64 max_size;
+
+ /* first extent starting offset */
+ u64 window_start;
+
+ struct btrfs_block_group_cache *block_group;
+ /*
+ * when a cluster is allocated from a block group, we put the
+ * cluster onto a list in the block group so that it can
+ * be freed before the block group is freed.
+ */
+ struct list_head block_group_list;
};
struct btrfs_block_group_cache {
@@ -667,6 +685,11 @@ struct btrfs_block_group_cache {
/* usage count */
atomic_t count;
+
+ /* List of struct btrfs_free_clusters for this block group.
+ * Today it will only have one thing on it, but that may change
+ */
+ struct list_head cluster_list;
};
struct btrfs_leaf_ref_tree {
@@ -838,8 +861,12 @@ struct btrfs_fs_info {
spinlock_t delalloc_lock;
spinlock_t new_trans_lock;
u64 delalloc_bytes;
- u64 last_alloc;
- u64 last_data_alloc;
+
+ /* data_alloc_cluster is only used in ssd mode */
+ struct btrfs_free_cluster data_alloc_cluster;
+
+ /* all metadata allocations go through this cluster */
+ struct btrfs_free_cluster meta_alloc_cluster;
spinlock_t ref_cache_lock;
u64 total_ref_cache_size;
@@ -1747,6 +1774,7 @@ static inline struct dentry *fdentry(struct file *file)
}
/* extent-tree.c */
+void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
struct btrfs_root *root, unsigned long count);
int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len);
@@ -2173,16 +2201,4 @@ int btrfs_check_acl(struct inode *inode, int mask);
int btrfs_init_acl(struct inode *inode, struct inode *dir);
int btrfs_acl_chmod(struct inode *inode);
-/* free-space-cache.c */
-int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
- u64 bytenr, u64 size);
-int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
- u64 bytenr, u64 size);
-void btrfs_remove_free_space_cache(struct btrfs_block_group_cache
- *block_group);
-u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
- u64 offset, u64 bytes, u64 empty_size);
-void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group,
- u64 bytes);
-u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group);
#endif
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ea59ebfa505d..e68ef7b456b0 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -38,6 +38,7 @@
#include "locking.h"
#include "ref-cache.h"
#include "tree-log.h"
+#include "free-space-cache.h"
static struct extent_io_ops btree_extent_io_ops;
static void end_workqueue_fn(struct btrfs_work *work);
@@ -1652,6 +1653,10 @@ struct btrfs_root *open_ctree(struct super_block *sb,
mutex_init(&fs_info->cleaner_mutex);
mutex_init(&fs_info->volume_mutex);
mutex_init(&fs_info->tree_reloc_mutex);
+
+ btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
+ btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
+
init_waitqueue_head(&fs_info->transaction_throttle);
init_waitqueue_head(&fs_info->transaction_wait);
init_waitqueue_head(&fs_info->async_submit_wait);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 15d62a9214b7..178df4c67de4 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -31,6 +31,7 @@
#include "volumes.h"
#include "locking.h"
#include "ref-cache.h"
+#include "free-space-cache.h"
#define PENDING_EXTENT_INSERT 0
#define PENDING_EXTENT_DELETE 1
@@ -324,7 +325,7 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(
return cache;
}
-static inline void put_block_group(struct btrfs_block_group_cache *cache)
+void btrfs_put_block_group(struct btrfs_block_group_cache *cache)
{
if (atomic_dec_and_test(&cache->count))
kfree(cache);
@@ -397,12 +398,12 @@ again:
div_factor(cache->key.offset, factor)) {
group_start = cache->key.objectid;
spin_unlock(&cache->lock);
- put_block_group(cache);
+ btrfs_put_block_group(cache);
goto found;
}
}
spin_unlock(&cache->lock);
- put_block_group(cache);
+ btrfs_put_block_group(cache);
cond_resched();
}
if (!wrapped) {
@@ -1592,7 +1593,7 @@ int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
if (!block_group || block_group->ro)
readonly = 1;
if (block_group)
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
return readonly;
}
@@ -2016,7 +2017,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
WARN_ON(ret);
}
}
- put_block_group(cache);
+ btrfs_put_block_group(cache);
total -= num_bytes;
bytenr += num_bytes;
}
@@ -2033,7 +2034,7 @@ static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
return 0;
bytenr = cache->key.objectid;
- put_block_group(cache);
+ btrfs_put_block_group(cache);
return bytenr;
}
@@ -2077,7 +2078,7 @@ int btrfs_update_pinned_extents(struct btrfs_root *root,
if (cache->cached)
btrfs_add_free_space(cache, bytenr, len);
}
- put_block_group(cache);
+ btrfs_put_block_group(cache);
bytenr += len;
num -= len;
}
@@ -2108,7 +2109,7 @@ static int update_reserved_extents(struct btrfs_root *root,
}
spin_unlock(&cache->lock);
spin_unlock(&cache->space_info->lock);
- put_block_group(cache);
+ btrfs_put_block_group(cache);
bytenr += len;
num -= len;
}
@@ -2543,12 +2544,13 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
{
int ret = 0;
struct btrfs_root *root = orig_root->fs_info->extent_root;
- u64 *last_ptr = NULL;
+ struct btrfs_free_cluster *last_ptr = NULL;
struct btrfs_block_group_cache *block_group = NULL;
int empty_cluster = 2 * 1024 * 1024;
int allowed_chunk_alloc = 0;
- int using_hint = 0;
struct btrfs_space_info *space_info;
+ int last_ptr_loop = 0;
+ int loop = 0;
WARN_ON(num_bytes < root->sectorsize);
btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
@@ -2561,38 +2563,39 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
allowed_chunk_alloc = 1;
if (data & BTRFS_BLOCK_GROUP_METADATA) {
- last_ptr = &root->fs_info->last_alloc;
+ last_ptr = &root->fs_info->meta_alloc_cluster;
if (!btrfs_test_opt(root, SSD))
empty_cluster = 64 * 1024;
}
- if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD))
- last_ptr = &root->fs_info->last_data_alloc;
+ if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD)) {
+ last_ptr = &root->fs_info->data_alloc_cluster;
+ }
if (last_ptr) {
- if (*last_ptr)
- hint_byte = *last_ptr;
- else
- empty_size += empty_cluster;
- } else {
- empty_cluster = 0;
+ spin_lock(&last_ptr->lock);
+ if (last_ptr->block_group)
+ hint_byte = last_ptr->window_start;
+ spin_unlock(&last_ptr->lock);
}
+
search_start = max(search_start, first_logical_byte(root, 0));
search_start = max(search_start, hint_byte);
+ if (!last_ptr) {
+ empty_cluster = 0;
+ loop = 1;
+ }
+
if (search_start == hint_byte) {
- using_hint = 1;
block_group = btrfs_lookup_block_group(root->fs_info,
search_start);
if (block_group && block_group_bits(block_group, data)) {
down_read(&space_info->groups_sem);
goto have_block_group;
} else if (block_group) {
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
}
-
- empty_size += empty_cluster;
- using_hint = 0;
}
search:
@@ -2609,7 +2612,7 @@ have_block_group:
ret = cache_block_group(root, block_group);
mutex_unlock(&block_group->cache_mutex);
if (ret) {
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
break;
}
}
@@ -2617,11 +2620,88 @@ have_block_group:
if (unlikely(block_group->ro))
goto loop;
+ if (last_ptr) {
+ /*
+ * the refill lock keeps out other
+ * people trying to start a new cluster
+ */
+ spin_lock(&last_ptr->refill_lock);
+ offset = btrfs_alloc_from_cluster(block_group, last_ptr,
+ num_bytes, search_start);
+ if (offset) {
+ /* we have a block, we're done */
+ spin_unlock(&last_ptr->refill_lock);
+ goto checks;
+ }
+
+ spin_lock(&last_ptr->lock);
+ /*
+ * whoops, this cluster doesn't actually point to
+ * this block group. Get a ref on the block
+ * group is does point to and try again
+ */
+ if (!last_ptr_loop && last_ptr->block_group &&
+ last_ptr->block_group != block_group) {
+
+ btrfs_put_block_group(block_group);
+ block_group = last_ptr->block_group;
+ atomic_inc(&block_group->count);
+ spin_unlock(&last_ptr->lock);
+ spin_unlock(&last_ptr->refill_lock);
+
+ last_ptr_loop = 1;
+ search_start = block_group->key.objectid;
+ goto have_block_group;
+ }
+ spin_unlock(&last_ptr->lock);
+
+ /*
+ * this cluster didn't work out, free it and
+ * start over
+ */
+ btrfs_return_cluster_to_free_space(NULL, last_ptr);
+
+ last_ptr_loop = 0;
+
+ /* allocate a cluster in this block group */
+ ret = btrfs_find_space_cluster(trans,
+ block_group, last_ptr,
+ offset, num_bytes,
+ empty_cluster + empty_size);
+ if (ret == 0) {
+ /*
+ * now pull our allocation out of this
+ * cluster
+ */
+ offset = btrfs_alloc_from_cluster(block_group,
+ last_ptr, num_bytes,
+ search_start);
+ if (offset) {
+ /* we found one, proceed */
+ spin_unlock(&last_ptr->refill_lock);
+ goto checks;
+ }
+ }
+ /*
+ * at this point we either didn't find a cluster
+ * or we weren't able to allocate a block from our
+ * cluster. Free the cluster we've been trying
+ * to use, and go to the next block group
+ */
+ if (loop < 2) {
+ btrfs_return_cluster_to_free_space(NULL,
+ last_ptr);
+ spin_unlock(&last_ptr->refill_lock);
+ goto loop;
+ }
+ spin_unlock(&last_ptr->refill_lock);
+ }
+
offset = btrfs_find_space_for_alloc(block_group, search_start,
num_bytes, empty_size);
if (!offset)
goto loop;
-
+checks:
search_start = stripe_align(root, offset);
/* move on to the next group */
@@ -2637,11 +2717,6 @@ have_block_group:
goto loop;
}
- if (using_hint && search_start > hint_byte) {
- btrfs_add_free_space(block_group, offset, num_bytes);
- goto loop;
- }
-
if (exclude_nr > 0 &&
(search_start + num_bytes > exclude_start &&
search_start < exclude_start + exclude_nr)) {
@@ -2670,33 +2745,33 @@ have_block_group:
/* we are all good, lets return */
break;
loop:
- put_block_group(block_group);
- if (using_hint) {
- empty_size += empty_cluster;
- using_hint = 0;
- up_read(&space_info->groups_sem);
- goto search;
- }
+ btrfs_put_block_group(block_group);
}
up_read(&space_info->groups_sem);
- if (!ins->objectid && (empty_size || allowed_chunk_alloc)) {
- int try_again = empty_size;
-
- empty_size = 0;
+ /* loop == 0, try to find a clustered alloc in every block group
+ * loop == 1, try again after forcing a chunk allocation
+ * loop == 2, set empty_size and empty_cluster to 0 and try again
+ */
+ if (!ins->objectid && loop < 3 &&
+ (empty_size || empty_cluster || allowed_chunk_alloc)) {
+ if (loop >= 2) {
+ empty_size = 0;
+ empty_cluster = 0;
+ }
if (allowed_chunk_alloc) {
ret = do_chunk_alloc(trans, root, num_bytes +
2 * 1024 * 1024, data, 1);
- if (!ret)
- try_again = 1;
allowed_chunk_alloc = 0;
} else {
space_info->force_alloc = 1;
}
- if (try_again)
+ if (loop < 3) {
+ loop++;
goto search;
+ }
ret = -ENOSPC;
} else if (!ins->objectid) {
ret = -ENOSPC;
@@ -2707,9 +2782,7 @@ loop:
if (!(data & BTRFS_BLOCK_GROUP_DATA))
trans->block_group = block_group->key.objectid;
- if (last_ptr)
- *last_ptr = ins->objectid + ins->offset;
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
ret = 0;
}
@@ -2817,7 +2890,7 @@ int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
ret = btrfs_discard_extent(root, start, len);
btrfs_add_free_space(cache, start, len);
- put_block_group(cache);
+ btrfs_put_block_group(cache);
update_reserved_extents(root, start, len, 0);
return ret;
@@ -2955,7 +3028,7 @@ int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans,
ret = btrfs_remove_free_space(block_group, ins->objectid,
ins->offset);
BUG_ON(ret);
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
ref_generation, owner, ins, 1);
return ret;
@@ -5644,7 +5717,7 @@ next:
WARN_ON(block_group->reserved > 0);
WARN_ON(btrfs_block_group_used(&block_group->item) > 0);
spin_unlock(&block_group->lock);
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
ret = 0;
out:
btrfs_free_path(path);
@@ -5774,6 +5847,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
spin_lock_init(&cache->tree_lock);
mutex_init(&cache->cache_mutex);
INIT_LIST_HEAD(&cache->list);
+ INIT_LIST_HEAD(&cache->cluster_list);
read_extent_buffer(leaf, &cache->item,
btrfs_item_ptr_offset(leaf, path->slots[0]),
sizeof(cache->item));
@@ -5830,6 +5904,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
spin_lock_init(&cache->tree_lock);
mutex_init(&cache->cache_mutex);
INIT_LIST_HEAD(&cache->list);
+ INIT_LIST_HEAD(&cache->cluster_list);
btrfs_set_block_group_used(&cache->item, bytes_used);
btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
@@ -5889,8 +5964,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
spin_unlock(&block_group->space_info->lock);
block_group->space_info->full = 0;
- put_block_group(block_group);
- put_block_group(block_group);
+ btrfs_put_block_group(block_group);
+ btrfs_put_block_group(block_group);
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
if (ret > 0)
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index df19b60eef61..3fdadd28e935 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -18,6 +18,15 @@
#include <linux/sched.h>
#include "ctree.h"
+#include "free-space-cache.h"
+#include "transaction.h"
+
+struct btrfs_free_space {
+ struct rb_node bytes_index;
+ struct rb_node offset_index;
+ u64 offset;
+ u64 bytes;
+};
static int tree_insert_offset(struct rb_root *root, u64 offset,
struct rb_node *node)
@@ -371,12 +380,58 @@ u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group)
return ret;
}
+/*
+ * for a given cluster, put all of its extents back into the free
+ * space cache. If the block group passed doesn't match the block group
+ * pointed to by the cluster, someone else raced in and freed the
+ * cluster already. In that case, we just return without changing anything
+ */
+static int
+__btrfs_return_cluster_to_free_space(
+ struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster)
+{
+ struct btrfs_free_space *entry;
+ struct rb_node *node;
+
+ spin_lock(&cluster->lock);
+ if (cluster->block_group != block_group)
+ goto out;
+
+ cluster->window_start = 0;
+ node = rb_first(&cluster->root);
+ while(node) {
+ entry = rb_entry(node, struct btrfs_free_space, offset_index);
+ node = rb_next(&entry->offset_index);
+ rb_erase(&entry->offset_index, &cluster->root);
+ link_free_space(block_group, entry);
+ }
+ list_del_init(&cluster->block_group_list);
+
+ btrfs_put_block_group(cluster->block_group);
+ cluster->block_group = NULL;
+ cluster->root.rb_node = NULL;
+out:
+ spin_unlock(&cluster->lock);
+ return 0;
+}
+
void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group)
{
struct btrfs_free_space *info;
struct rb_node *node;
+ struct btrfs_free_cluster *cluster;
+ struct btrfs_free_cluster *safe;
spin_lock(&block_group->tree_lock);
+
+ list_for_each_entry_safe(cluster, safe, &block_group->cluster_list,
+ block_group_list) {
+
+ WARN_ON(cluster->block_group != block_group);
+ __btrfs_return_cluster_to_free_space(block_group, cluster);
+ }
+
while ((node = rb_last(&block_group->free_space_bytes)) != NULL) {
info = rb_entry(node, struct btrfs_free_space, bytes_index);
unlink_free_space(block_group, info);
@@ -417,3 +472,245 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
return ret;
}
+
+/*
+ * given a cluster, put all of its extents back into the free space
+ * cache. If a block group is passed, this function will only free
+ * a cluster that belongs to the passed block group.
+ *
+ * Otherwise, it'll get a reference on the block group pointed to by the
+ * cluster and remove the cluster from it.
+ */
+int btrfs_return_cluster_to_free_space(
+ struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster)
+{
+ int ret;
+
+ /* first, get a safe pointer to the block group */
+ spin_lock(&cluster->lock);
+ if (!block_group) {
+ block_group = cluster->block_group;
+ if (!block_group) {
+ spin_unlock(&cluster->lock);
+ return 0;
+ }
+ } else if (cluster->block_group != block_group) {
+ /* someone else has already freed it don't redo their work */
+ spin_unlock(&cluster->lock);
+ return 0;
+ }
+ atomic_inc(&block_group->count);
+ spin_unlock(&cluster->lock);
+
+ /* now return any extents the cluster had on it */
+ spin_lock(&block_group->tree_lock);
+ ret = __btrfs_return_cluster_to_free_space(block_group, cluster);
+ spin_unlock(&block_group->tree_lock);
+
+ /* finally drop our ref */
+ btrfs_put_block_group(block_group);
+ return ret;
+}
+
+/*
+ * given a cluster, try to allocate 'bytes' from it, returns 0
+ * if it couldn't find anything suitably large, or a logical disk offset
+ * if things worked out
+ */
+u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster, u64 bytes,
+ u64 min_start)
+{
+ struct btrfs_free_space *entry = NULL;
+ struct rb_node *node;
+ u64 ret = 0;
+
+ spin_lock(&cluster->lock);
+ if (bytes > cluster->max_size)
+ goto out;
+
+ if (cluster->block_group != block_group)
+ goto out;
+
+ node = rb_first(&cluster->root);
+ if (!node)
+ goto out;
+
+ entry = rb_entry(node, struct btrfs_free_space, offset_index);
+
+ while(1) {
+ if (entry->bytes < bytes || entry->offset < min_start) {
+ struct rb_node *node;
+
+ node = rb_next(&entry->offset_index);
+ if (!node)
+ break;
+ entry = rb_entry(node, struct btrfs_free_space,
+ offset_index);
+ continue;
+ }
+ ret = entry->offset;
+
+ entry->offset += bytes;
+ entry->bytes -= bytes;
+
+ if (entry->bytes == 0) {
+ rb_erase(&entry->offset_index, &cluster->root);
+ kfree(entry);
+ }
+ break;
+ }
+out:
+ spin_unlock(&cluster->lock);
+ return ret;
+}
+
+/*
+ * here we try to find a cluster of blocks in a block group. The goal
+ * is to find at least bytes free and up to empty_size + bytes free.
+ * We might not find them all in one contiguous area.
+ *
+ * returns zero and sets up cluster if things worked out, otherwise
+ * it returns -enospc
+ */
+int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
+ struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster,
+ u64 offset, u64 bytes, u64 empty_size)
+{
+ struct btrfs_free_space *entry = NULL;
+ struct rb_node *node;
+ struct btrfs_free_space *next;
+ struct btrfs_free_space *last;
+ u64 min_bytes;
+ u64 window_start;
+ u64 window_free;
+ u64 max_extent = 0;
+ int total_retries = 0;
+ int ret;
+
+ /* for metadata, allow allocates with more holes */
+ if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) {
+ /*
+ * we want to do larger allocations when we are
+ * flushing out the delayed refs, it helps prevent
+ * making more work as we go along.
+ */
+ if (trans->transaction->delayed_refs.flushing)
+ min_bytes = max(bytes, (bytes + empty_size) >> 1);
+ else
+ min_bytes = max(bytes, (bytes + empty_size) >> 4);
+ } else
+ min_bytes = max(bytes, (bytes + empty_size) >> 2);
+
+ spin_lock(&block_group->tree_lock);
+ spin_lock(&cluster->lock);
+
+ /* someone already found a cluster, hooray */
+ if (cluster->block_group) {
+ ret = 0;
+ goto out;
+ }
+again:
+ min_bytes = min(min_bytes, bytes + empty_size);
+ entry = tree_search_bytes(&block_group->free_space_bytes,
+ offset, min_bytes);
+ if (!entry) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ window_start = entry->offset;
+ window_free = entry->bytes;
+ last = entry;
+ max_extent = entry->bytes;
+
+ while(1) {
+ /* out window is just right, lets fill it */
+ if (window_free >= bytes + empty_size)
+ break;
+
+ node = rb_next(&last->offset_index);
+ if (!node) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ next = rb_entry(node, struct btrfs_free_space, offset_index);
+
+ /*
+ * we haven't filled the empty size and the window is
+ * very large. reset and try again
+ */
+ if (next->offset - window_start > (bytes + empty_size) * 2) {
+ entry = next;
+ window_start = entry->offset;
+ window_free = entry->bytes;
+ last = entry;
+ max_extent = 0;
+ total_retries++;
+ if (total_retries % 256 == 0) {
+ if (min_bytes >= (bytes + empty_size)) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ /*
+ * grow our allocation a bit, we're not having
+ * much luck
+ */
+ min_bytes *= 2;
+ goto again;
+ }
+ } else {
+ last = next;
+ window_free += next->bytes;
+ if (entry->bytes > max_extent)
+ max_extent = entry->bytes;
+ }
+ }
+
+ cluster->window_start = entry->offset;
+
+ /*
+ * now we've found our entries, pull them out of the free space
+ * cache and put them into the cluster rbtree
+ *
+ * The cluster includes an rbtree, but only uses the offset index
+ * of each free space cache entry.
+ */
+ while(1) {
+ node = rb_next(&entry->offset_index);
+ unlink_free_space(block_group, entry);
+ ret = tree_insert_offset(&cluster->root, entry->offset,
+ &entry->offset_index);
+ BUG_ON(ret);
+
+ if (!node || entry == last)
+ break;
+
+ entry = rb_entry(node, struct btrfs_free_space, offset_index);
+ }
+ ret = 0;
+ cluster->max_size = max_extent;
+ atomic_inc(&block_group->count);
+ list_add_tail(&cluster->block_group_list, &block_group->cluster_list);
+ cluster->block_group = block_group;
+out:
+ spin_unlock(&cluster->lock);
+ spin_unlock(&block_group->tree_lock);
+
+ return ret;
+}
+
+/*
+ * simple code to zero out a cluster
+ */
+void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster)
+{
+ spin_lock_init(&cluster->lock);
+ spin_lock_init(&cluster->refill_lock);
+ cluster->root.rb_node = NULL;
+ cluster->max_size = 0;
+ INIT_LIST_HEAD(&cluster->block_group_list);
+ cluster->block_group = NULL;
+}
+
diff --git a/fs/btrfs/free-space-cache.h b/fs/btrfs/free-space-cache.h
new file mode 100644
index 000000000000..ab0bdc0a63ce
--- /dev/null
+++ b/fs/btrfs/free-space-cache.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2009 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef __BTRFS_FREE_SPACE_CACHE
+#define __BTRFS_FREE_SPACE_CACHE
+
+int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
+ u64 bytenr, u64 size);
+int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
+ u64 bytenr, u64 size);
+void btrfs_remove_free_space_cache(struct btrfs_block_group_cache
+ *block_group);
+u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes, u64 empty_size);
+void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group,
+ u64 bytes);
+u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group);
+int btrfs_find_space_cluster(struct btrfs_trans_handle *trans,
+ struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster,
+ u64 offset, u64 bytes, u64 empty_size);
+void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster);
+u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster, u64 bytes,
+ u64 min_start);
+int btrfs_return_cluster_to_free_space(
+ struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_cluster *cluster);
+#endif
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 664782c6a2df..3e8225de4e9d 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -53,8 +53,6 @@ static noinline int join_transaction(struct btrfs_root *root)
GFP_NOFS);
BUG_ON(!cur_trans);
root->fs_info->generation++;
- root->fs_info->last_alloc = 0;
- root->fs_info->last_data_alloc = 0;
cur_trans->num_writers = 1;
cur_trans->num_joined = 0;
cur_trans->transid = root->fs_info->generation;