Btrfs: Fix extent_buffer usage when nodesize != leafsize

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

fs/btrfs/disk-io.c

@@ -197,9 +197,23 @@ int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 	if (found_start != start) {
 		printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n",
 		       start, found_start, len);
+		WARN_ON(1);
+		goto err;
+	}
+	if (eb->first_page != page) {
+		printk("bad first page %lu %lu\n", eb->first_page->index,
+		       page->index);
+		WARN_ON(1);
+		goto err;
+	}
+	if (!PageUptodate(page)) {
+		printk("csum not up to date page %lu\n", page->index);
+		WARN_ON(1);
+		goto err;
 	}
 	found_level = btrfs_header_level(eb);
 	csum_tree_block(root, eb, 0);
+err:
 	free_extent_buffer(eb);
 out:
 	return 0;
@@ -368,7 +382,10 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		     struct extent_buffer *buf)
 {
 	struct inode *btree_inode = root->fs_info->btree_inode;
-	clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
+	if (btrfs_header_generation(buf) ==
+	    root->fs_info->running_transaction->transid)
+		clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree,
+					  buf);
 	return 0;
 }
 
@@ -897,8 +914,11 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 
 void btrfs_throttle(struct btrfs_root *root)
 {
-	if (root->fs_info->throttles)
-		congestion_wait(WRITE, HZ/10);
+	struct backing_dev_info *bdi;
+
+	bdi = root->fs_info->sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
+	if (root->fs_info->throttles && bdi_write_congested(bdi))
+		congestion_wait(WRITE, HZ/20);
 }
 
 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)

fs/btrfs/extent-tree.c

@@ -1212,6 +1212,7 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
 				u64 header_transid =
 					btrfs_header_generation(buf);
 				if (header_transid == transid) {
+					clean_tree_block(NULL, root, buf);
 					free_extent_buffer(buf);
 					return 1;
 				}
@@ -1249,7 +1250,6 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
 	key.objectid = bytenr;
 	btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
 	key.offset = num_bytes;
-
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -1648,8 +1648,6 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
 			       search_start, search_end, hint_byte, ins,
 			       trans->alloc_exclude_start,
 			       trans->alloc_exclude_nr, data);
-if (ret)
-printk("find free extent returns %d\n", ret);
 	BUG_ON(ret);
 	if (ret)
 		return ret;
@@ -1764,7 +1762,16 @@ struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 				  0, 0, 0);
 		return ERR_PTR(-ENOMEM);
 	}
+	btrfs_set_header_generation(buf, trans->transid);
+	clean_tree_block(trans, root, buf);
+	wait_on_tree_block_writeback(root, buf);
 	btrfs_set_buffer_uptodate(buf);
+
+	if (PageDirty(buf->first_page)) {
+		printk("page %lu dirty\n", buf->first_page->index);
+		WARN_ON(1);
+	}
+
 	set_extent_dirty(&trans->transaction->dirty_pages, buf->start,
 			 buf->start + buf->len - 1, GFP_NOFS);
 	set_extent_bits(&BTRFS_I(root->fs_info->btree_inode)->extent_tree,

fs/btrfs/extent_map.c

@@ -1663,6 +1663,13 @@ void set_page_extent_mapped(struct page *page)
 	}
 }
 
+void set_page_extent_head(struct page *page, unsigned long len)
+{
+	WARN_ON(page->private && page->private == EXTENT_PAGE_PRIVATE &&
+		PageDirty(page));
+	set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2);
+}
+
 /*
  * basic readpage implementation.  Locked extent state structs are inserted
  * into the tree that are removed when the IO is done (by the end_io
@@ -2490,8 +2497,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree,
 		mark_page_accessed(page0);
 		set_page_extent_mapped(page0);
 		WARN_ON(!PageUptodate(page0));
-		set_page_private(page0, EXTENT_PAGE_PRIVATE_FIRST_PAGE |
-				 len << 2);
+		set_page_extent_head(page0, len);
 	} else {
 		i = 0;
 	}
@@ -2505,8 +2511,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree,
 		mark_page_accessed(p);
 		if (i == 0) {
 			eb->first_page = p;
-			set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE |
-					 len << 2);
+			set_page_extent_head(p, len);
 		} else {
 			set_page_private(p, EXTENT_PAGE_PRIVATE);
 		}
@@ -2569,8 +2574,7 @@ struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree,
 
 		if (i == 0) {
 			eb->first_page = p;
-			set_page_private(p, EXTENT_PAGE_PRIVATE_FIRST_PAGE |
-					 len << 2);
+			set_page_extent_head(p, len);
 		} else {
 			set_page_private(p, EXTENT_PAGE_PRIVATE);
 		}
@@ -2643,6 +2647,11 @@ int clear_extent_buffer_dirty(struct extent_map_tree *tree,
 	for (i = 0; i < num_pages; i++) {
 		page = extent_buffer_page(eb, i);
 		lock_page(page);
+		if (i == 0)
+			set_page_extent_head(page, eb->len);
+		else
+			set_page_private(page, EXTENT_PAGE_PRIVATE);
+
 		/*
 		 * if we're on the last page or the first page and the
 		 * block isn't aligned on a page boundary, do extra checks
@@ -2697,9 +2706,12 @@ int set_extent_buffer_dirty(struct extent_map_tree *tree,
 		 */
 		if (i == 0) {
 			lock_page(page);
-			set_page_private(page,
-					 EXTENT_PAGE_PRIVATE_FIRST_PAGE |
-					 eb->len << 2);
+			set_page_extent_head(page, eb->len);
+		} else if (PagePrivate(page) &&
+			   page->private != EXTENT_PAGE_PRIVATE) {
+			lock_page(page);
+			set_page_extent_mapped(page);
+			unlock_page(page);
 		}
 		__set_page_dirty_nobuffers(extent_buffer_page(eb, i));
 		if (i == 0)