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path: root/fs/btrfs/free-space-cache.c
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Diffstat (limited to 'fs/btrfs/free-space-cache.c')
-rw-r--r--fs/btrfs/free-space-cache.c162
1 files changed, 100 insertions, 62 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 60d68426695..a0390657451 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -987,11 +987,18 @@ tree_search_offset(struct btrfs_block_group_cache *block_group,
return entry;
}
-static void unlink_free_space(struct btrfs_block_group_cache *block_group,
- struct btrfs_free_space *info)
+static inline void
+__unlink_free_space(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_space *info)
{
rb_erase(&info->offset_index, &block_group->free_space_offset);
block_group->free_extents--;
+}
+
+static void unlink_free_space(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_space *info)
+{
+ __unlink_free_space(block_group, info);
block_group->free_space -= info->bytes;
}
@@ -1016,14 +1023,18 @@ static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
u64 max_bytes;
u64 bitmap_bytes;
u64 extent_bytes;
+ u64 size = block_group->key.offset;
/*
* The goal is to keep the total amount of memory used per 1gb of space
* at or below 32k, so we need to adjust how much memory we allow to be
* used by extent based free space tracking
*/
- max_bytes = MAX_CACHE_BYTES_PER_GIG *
- (div64_u64(block_group->key.offset, 1024 * 1024 * 1024));
+ if (size < 1024 * 1024 * 1024)
+ max_bytes = MAX_CACHE_BYTES_PER_GIG;
+ else
+ max_bytes = MAX_CACHE_BYTES_PER_GIG *
+ div64_u64(size, 1024 * 1024 * 1024);
/*
* we want to account for 1 more bitmap than what we have so we can make
@@ -1171,6 +1182,16 @@ static void add_new_bitmap(struct btrfs_block_group_cache *block_group,
recalculate_thresholds(block_group);
}
+static void free_bitmap(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_space *bitmap_info)
+{
+ unlink_free_space(block_group, bitmap_info);
+ kfree(bitmap_info->bitmap);
+ kfree(bitmap_info);
+ block_group->total_bitmaps--;
+ recalculate_thresholds(block_group);
+}
+
static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group,
struct btrfs_free_space *bitmap_info,
u64 *offset, u64 *bytes)
@@ -1195,6 +1216,7 @@ again:
*/
search_start = *offset;
search_bytes = *bytes;
+ search_bytes = min(search_bytes, end - search_start + 1);
ret = search_bitmap(block_group, bitmap_info, &search_start,
&search_bytes);
BUG_ON(ret < 0 || search_start != *offset);
@@ -1211,13 +1233,8 @@ again:
if (*bytes) {
struct rb_node *next = rb_next(&bitmap_info->offset_index);
- if (!bitmap_info->bytes) {
- unlink_free_space(block_group, bitmap_info);
- kfree(bitmap_info->bitmap);
- kfree(bitmap_info);
- block_group->total_bitmaps--;
- recalculate_thresholds(block_group);
- }
+ if (!bitmap_info->bytes)
+ free_bitmap(block_group, bitmap_info);
/*
* no entry after this bitmap, but we still have bytes to
@@ -1250,13 +1267,8 @@ again:
return -EAGAIN;
goto again;
- } else if (!bitmap_info->bytes) {
- unlink_free_space(block_group, bitmap_info);
- kfree(bitmap_info->bitmap);
- kfree(bitmap_info);
- block_group->total_bitmaps--;
- recalculate_thresholds(block_group);
- }
+ } else if (!bitmap_info->bytes)
+ free_bitmap(block_group, bitmap_info);
return 0;
}
@@ -1359,22 +1371,14 @@ out:
return ret;
}
-int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
- u64 offset, u64 bytes)
+bool try_merge_free_space(struct btrfs_block_group_cache *block_group,
+ struct btrfs_free_space *info, bool update_stat)
{
- struct btrfs_free_space *right_info = NULL;
- struct btrfs_free_space *left_info = NULL;
- struct btrfs_free_space *info = NULL;
- int ret = 0;
-
- info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS);
- if (!info)
- return -ENOMEM;
-
- info->offset = offset;
- info->bytes = bytes;
-
- spin_lock(&block_group->tree_lock);
+ struct btrfs_free_space *left_info;
+ struct btrfs_free_space *right_info;
+ bool merged = false;
+ u64 offset = info->offset;
+ u64 bytes = info->bytes;
/*
* first we want to see if there is free space adjacent to the range we
@@ -1388,37 +1392,62 @@ int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
else
left_info = tree_search_offset(block_group, offset - 1, 0, 0);
- /*
- * If there was no extent directly to the left or right of this new
- * extent then we know we're going to have to allocate a new extent, so
- * before we do that see if we need to drop this into a bitmap
- */
- if ((!left_info || left_info->bitmap) &&
- (!right_info || right_info->bitmap)) {
- ret = insert_into_bitmap(block_group, info);
-
- if (ret < 0) {
- goto out;
- } else if (ret) {
- ret = 0;
- goto out;
- }
- }
-
if (right_info && !right_info->bitmap) {
- unlink_free_space(block_group, right_info);
+ if (update_stat)
+ unlink_free_space(block_group, right_info);
+ else
+ __unlink_free_space(block_group, right_info);
info->bytes += right_info->bytes;
kfree(right_info);
+ merged = true;
}
if (left_info && !left_info->bitmap &&
left_info->offset + left_info->bytes == offset) {
- unlink_free_space(block_group, left_info);
+ if (update_stat)
+ unlink_free_space(block_group, left_info);
+ else
+ __unlink_free_space(block_group, left_info);
info->offset = left_info->offset;
info->bytes += left_info->bytes;
kfree(left_info);
+ merged = true;
}
+ return merged;
+}
+
+int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
+ u64 offset, u64 bytes)
+{
+ struct btrfs_free_space *info;
+ int ret = 0;
+
+ info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS);
+ if (!info)
+ return -ENOMEM;
+
+ info->offset = offset;
+ info->bytes = bytes;
+
+ spin_lock(&block_group->tree_lock);
+
+ if (try_merge_free_space(block_group, info, true))
+ goto link;
+
+ /*
+ * There was no extent directly to the left or right of this new
+ * extent then we know we're going to have to allocate a new extent, so
+ * before we do that see if we need to drop this into a bitmap
+ */
+ ret = insert_into_bitmap(block_group, info);
+ if (ret < 0) {
+ goto out;
+ } else if (ret) {
+ ret = 0;
+ goto out;
+ }
+link:
ret = link_free_space(block_group, info);
if (ret)
kfree(info);
@@ -1621,6 +1650,7 @@ __btrfs_return_cluster_to_free_space(
node = rb_next(&entry->offset_index);
rb_erase(&entry->offset_index, &cluster->root);
BUG_ON(entry->bitmap);
+ try_merge_free_space(block_group, entry, false);
tree_insert_offset(&block_group->free_space_offset,
entry->offset, &entry->offset_index, 0);
}
@@ -1685,13 +1715,8 @@ u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
ret = offset;
if (entry->bitmap) {
bitmap_clear_bits(block_group, entry, offset, bytes);
- if (!entry->bytes) {
- unlink_free_space(block_group, entry);
- kfree(entry->bitmap);
- kfree(entry);
- block_group->total_bitmaps--;
- recalculate_thresholds(block_group);
- }
+ if (!entry->bytes)
+ free_bitmap(block_group, entry);
} else {
unlink_free_space(block_group, entry);
entry->offset += bytes;
@@ -1789,6 +1814,8 @@ static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
ret = search_start;
bitmap_clear_bits(block_group, entry, ret, bytes);
+ if (entry->bytes == 0)
+ free_bitmap(block_group, entry);
out:
spin_unlock(&cluster->lock);
spin_unlock(&block_group->tree_lock);
@@ -1842,15 +1869,26 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
entry->offset += bytes;
entry->bytes -= bytes;
- if (entry->bytes == 0) {
+ if (entry->bytes == 0)
rb_erase(&entry->offset_index, &cluster->root);
- kfree(entry);
- }
break;
}
out:
spin_unlock(&cluster->lock);
+ if (!ret)
+ return 0;
+
+ spin_lock(&block_group->tree_lock);
+
+ block_group->free_space -= bytes;
+ if (entry->bytes == 0) {
+ block_group->free_extents--;
+ kfree(entry);
+ }
+
+ spin_unlock(&block_group->tree_lock);
+
return ret;
}