Minor fixes to free-space-tree patchset, for 4.5

index b1d920b30070..0e1e61a7ec23 100644
@@ -82,18 +82,18 @@ void btrfs_destroy_test_fs(void)
 struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(void)
 {
 	struct btrfs_fs_info *fs_info = kzalloc(sizeof(struct btrfs_fs_info),
-						GFP_NOFS);
+						GFP_KERNEL);
 
 	if (!fs_info)
 		return fs_info;
 	fs_info->fs_devices = kzalloc(sizeof(struct btrfs_fs_devices),
-				      GFP_NOFS);
+				      GFP_KERNEL);
 	if (!fs_info->fs_devices) {
 		kfree(fs_info);
 		return NULL;
 	}
 	fs_info->super_copy = kzalloc(sizeof(struct btrfs_super_block),
-				      GFP_NOFS);
+				      GFP_KERNEL);
 	if (!fs_info->super_copy) {
 		kfree(fs_info->fs_devices);
 		kfree(fs_info);

@@ -180,11 +180,11 @@ btrfs_alloc_dummy_block_group(unsigned long length)
 {
 	struct btrfs_block_group_cache *cache;
 
-	cache = kzalloc(sizeof(*cache), GFP_NOFS);
+	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
 	if (!cache)
 		return NULL;
 	cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
-					GFP_NOFS);
+					GFP_KERNEL);
 	if (!cache->free_space_ctl) {
 		kfree(cache);
 		return NULL;

index e29fa297e053..669b58201e36 100644
@@ -94,7 +94,7 @@ static int test_find_delalloc(void)
 	 * test.
 	 */
 	for (index = 0; index < (total_dirty >> PAGE_CACHE_SHIFT); index++) {
-		page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
+		page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
 		if (!page) {
 			test_msg("Failed to allocate test page\n");
 			ret = -ENOMEM;

@@ -113,7 +113,7 @@ static int test_find_delalloc(void)
 	 * |--- delalloc ---|
 	 * |---  search  ---|
 	 */
-	set_extent_delalloc(&tmp, 0, 4095, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, 0, 4095, NULL, GFP_KERNEL);
 	start = 0;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,

@@ -144,7 +144,7 @@ static int test_find_delalloc(void)
 		test_msg("Couldn't find the locked page\n");
 		goto out_bits;
 	}
-	set_extent_delalloc(&tmp, 4096, max_bytes - 1, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, 4096, max_bytes - 1, NULL, GFP_KERNEL);
 	start = test_start;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,

@@ -199,7 +199,7 @@ static int test_find_delalloc(void)
 	 *
 	 * We are re-using our test_start from above since it works out well.
 	 */
-	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, NULL, GFP_KERNEL);
 	start = test_start;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,

@@ -262,7 +262,7 @@ static int test_find_delalloc(void)
 	}
 	ret = 0;
 out_bits:
-	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1, GFP_NOFS);
+	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1, GFP_KERNEL);
 out:
 	if (locked_page)
 		page_cache_release(locked_page);

@@ -360,7 +360,7 @@ static int test_eb_bitmaps(void)
 
 	test_msg("Running extent buffer bitmap tests\n");
 
-	bitmap = kmalloc(len, GFP_NOFS);
+	bitmap = kmalloc(len, GFP_KERNEL);
 	if (!bitmap) {
 		test_msg("Couldn't allocate test bitmap\n");
 		return -ENOMEM;

index 5de55fdd28bc..e2d3da02deee 100644
@@ -974,7 +974,7 @@ static int test_extent_accounting(void)
 			       (BTRFS_MAX_EXTENT_SIZE >> 1) + 4095,
 			       EXTENT_DELALLOC | EXTENT_DIRTY |
 			       EXTENT_UPTODATE | EXTENT_DO_ACCOUNTING, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;

@@ -1045,7 +1045,7 @@ static int test_extent_accounting(void)
 			       BTRFS_MAX_EXTENT_SIZE+8191,
 			       EXTENT_DIRTY | EXTENT_DELALLOC |
 			       EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;

@@ -1079,7 +1079,7 @@ static int test_extent_accounting(void)
 	ret = clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
 			       EXTENT_DIRTY | EXTENT_DELALLOC |
 			       EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;

@@ -1096,7 +1096,7 @@ static int test_extent_accounting(void)
 		clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
 				 EXTENT_DIRTY | EXTENT_DELALLOC |
 				 EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-				 NULL, GFP_NOFS);
+				 NULL, GFP_KERNEL);
 	iput(inode);
 	btrfs_free_dummy_root(root);
 	return ret;

index 393e36bd5845..0f33d58cb321 100644
@@ -153,6 +153,20 @@ static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize)
 
 static unsigned long *alloc_bitmap(u32 bitmap_size)
 {
+	void *mem;
+
+	/*
+	 * The allocation size varies, observed numbers were < 4K up to 16K.
+	 * Using vmalloc unconditionally would be too heavy, we'll try
+	 * contiguous allocations first.
+	 */
+	if  (bitmap_size <= PAGE_SIZE)
+		return kzalloc(bitmap_size, GFP_NOFS);
+
+	mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_NOWARN);
+	if (mem)
+		return mem;
+
 	return __vmalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_ZERO,
 			 PAGE_KERNEL);
 }

@@ -289,7 +303,7 @@ int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans,
 
 	ret = 0;
 out:
-	vfree(bitmap);
+	kvfree(bitmap);
 	if (ret)
 		btrfs_abort_transaction(trans, root, ret);
 	return ret;

@@ -438,7 +452,7 @@ int convert_free_space_to_extents(struct btrfs_trans_handle *trans,
 
 	ret = 0;
 out:
-	vfree(bitmap);
+	kvfree(bitmap);
 	if (ret)
 		btrfs_abort_transaction(trans, root, ret);
 	return ret;

index c67c129fe99a..ca78bf2ed287 100644
@@ -176,6 +176,7 @@ static struct btrfs_lockdep_keyset {
 	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
+	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	.name_stem = "free-space" },
 	{ .id = 0,				.name_stem = "tree"	},
 };
 

index ef6d8fc85853..c5540302402d 100644
@@ -575,7 +575,8 @@ static int is_cowonly_root(u64 root_objectid)
 	    root_objectid == BTRFS_TREE_LOG_OBJECTID ||
 	    root_objectid == BTRFS_CSUM_TREE_OBJECTID ||
 	    root_objectid == BTRFS_UUID_TREE_OBJECTID ||
-	    root_objectid == BTRFS_QUOTA_TREE_OBJECTID)
+	    root_objectid == BTRFS_QUOTA_TREE_OBJECTID ||
+	    root_objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
 		return 1;
 	return 0;
 }