From 728131d8e40c2a47c59ca91a806299c4708029f9 Mon Sep 17 00:00:00 2001
From: Chris Mason <chris.mason@oracle.com>
Date: Wed, 9 Apr 2008 16:28:12 -0400
Subject: [PATCH] Btrfs: Add additional debugging for metadata checksum
 failures

Signed-off-by: Chris Mason <chris.mason@oracle.com>
---
 fs/btrfs/disk-io.c   |  3 ++-
 fs/btrfs/extent_io.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++---
 fs/btrfs/extent_io.h |  2 ++
 3 files changed, 55 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index bc5bd5a..e444b99 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -283,6 +283,7 @@ static int btree_releasepage(struct page *page, gfp_t gfp_flags)
 	map = &BTRFS_I(page->mapping->host)->extent_tree;
 	ret = try_release_extent_mapping(map, tree, page, gfp_flags);
 	if (ret == 1) {
+		invalidate_extent_lru(tree, page_offset(page), PAGE_CACHE_SIZE);
 		ClearPagePrivate(page);
 		set_page_private(page, 0);
 		page_cache_release(page);
@@ -376,7 +377,6 @@ int btrfs_verify_block_csum(struct btrfs_root *root,
 		buf->flags |= EXTENT_CSUM;
 		return 0;
 	}
-
 	lock_extent(io_tree, buf->start, end, GFP_NOFS);
 
 	if (test_range_bit(io_tree, buf->start, end, EXTENT_CSUM, 1)) {
@@ -384,6 +384,7 @@ int btrfs_verify_block_csum(struct btrfs_root *root,
 		ret = 0;
 		goto out_unlock;
 	}
+WARN_ON(buf->flags & EXTENT_CSUM);
 
 	ret = csum_tree_block(root, buf, 1);
 	set_extent_bits(io_tree, buf->start, end, EXTENT_CSUM, GFP_NOFS);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 776c33f..13cc236 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2592,6 +2592,33 @@ static inline struct page *extent_buffer_page(struct extent_buffer *eb,
 	return p;
 }
 
+int invalidate_extent_lru(struct extent_io_tree *tree, u64 start,
+			  unsigned long len)
+{
+	struct list_head *lru = &tree->buffer_lru;
+	struct list_head *cur = lru->next;
+	struct extent_buffer *eb;
+	int found = 0;
+
+	spin_lock(&tree->lru_lock);
+	if (list_empty(lru))
+		goto out;
+
+	do {
+		eb = list_entry(cur, struct extent_buffer, lru);
+		if (eb->start <= start && eb->start + eb->len > start) {
+			eb->flags &= ~EXTENT_UPTODATE;
+		}
+		if (eb->start == start) {
+			eb->flags &= ~EXTENT_CSUM;
+		}
+		cur = cur->next;
+	} while (cur != lru);
+out:
+	spin_unlock(&tree->lru_lock);
+	return found;
+}
+
 static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
 						   u64 start,
 						   unsigned long len,
@@ -2909,10 +2936,32 @@ EXPORT_SYMBOL(set_extent_buffer_uptodate);
 int extent_buffer_uptodate(struct extent_io_tree *tree,
 			     struct extent_buffer *eb)
 {
+	int ret = 0;
+	int ret2;
+	int num_pages;
+	int i;
+	struct page *page;
+	int pg_uptodate = 1;
+
 	if (eb->flags & EXTENT_UPTODATE)
-		return 1;
-	return test_range_bit(tree, eb->start, eb->start + eb->len - 1,
+		ret = 1;
+
+	ret2  = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
 			   EXTENT_UPTODATE, 1);
+
+	num_pages = num_extent_pages(eb->start, eb->len);
+	for (i = 0; i < num_pages; i++) {
+		page = extent_buffer_page(eb, i);
+		if (!PageUptodate(page)) {
+			pg_uptodate = 0;
+			break;
+		}
+	}
+	if ((ret || ret2) && !pg_uptodate) {
+printk("uptodate error2 eb %Lu ret %d ret2 %d pg_uptodate %d\n", eb->start, ret, ret2, pg_uptodate);
+		WARN_ON(1);
+	}
+	return (ret || ret2);
 }
 EXPORT_SYMBOL(extent_buffer_uptodate);
 
@@ -2929,7 +2978,6 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 	unsigned long num_pages;
 	struct bio *bio = NULL;
 
-
 	if (eb->flags & EXTENT_UPTODATE)
 		return 0;
 
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 16d67a6..d9f5bc4 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -216,4 +216,6 @@ int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 		      unsigned long *map_start,
 		      unsigned long *map_len, int km);
 void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
+int invalidate_extent_lru(struct extent_io_tree *tree, u64 start,
+			  unsigned long len);
 #endif
-- 
2.7.4