Btrfs: Add debugging checks to track down corrupted metadata

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

fs/btrfs/disk-io.c

@@ -250,7 +250,7 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
 		if (!ret &&
 		    !verify_parent_transid(io_tree, eb, parent_transid))
 			return ret;
-
+printk("read extent buffer pages failed with ret %d mirror no %d\n", ret, mirror_num);
 		num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 					      eb->start, eb->len);
 		if (num_copies == 1)
@@ -348,6 +348,9 @@ int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 
 	found_start = btrfs_header_bytenr(eb);
 	if (found_start != start) {
+		printk("bad tree block start %llu %llu\n",
+		       (unsigned long long)found_start,
+		       (unsigned long long)eb->start);
 		ret = -EIO;
 		goto err;
 	}
@@ -709,6 +712,8 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 
 	if (ret == 0) {
 		buf->flags |= EXTENT_UPTODATE;
+	} else {
+		WARN_ON(1);
 	}
 	return buf;
 

fs/btrfs/extent_io.c

@@ -1811,6 +1811,7 @@ printk("2bad mapping end %Lu cur %Lu\n", end, cur);
 		}
 		/* the get_extent function already copied into the page */
 		if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) {
+			check_page_uptodate(tree, page);
 			unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
 			cur = cur + iosize;
 			page_offset += iosize;
@@ -2785,21 +2786,20 @@ int set_extent_buffer_dirty(struct extent_io_tree *tree,
 		 * properly set.  releasepage may drop page->private
 		 * on us if the page isn't already dirty.
 		 */
+		lock_page(page);
 		if (i == 0) {
-			lock_page(page);
 			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)
-			unlock_page(page);
+		set_extent_dirty(tree, page_offset(page),
+				 page_offset(page) + PAGE_CACHE_SIZE -1,
+				 GFP_NOFS);
+		unlock_page(page);
 	}
-	return set_extent_dirty(tree, eb->start,
-				eb->start + eb->len - 1, GFP_NOFS);
+	return 0;
 }
 EXPORT_SYMBOL(set_extent_buffer_dirty);
 
@@ -2952,6 +2952,9 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 	if (all_uptodate) {
 		if (start_i == 0)
 			eb->flags |= EXTENT_UPTODATE;
+		if (ret) {
+			printk("all up to date but ret is %d\n", ret);
+		}
 		goto unlock_exit;
 	}
 
@@ -2968,6 +2971,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 						      mirror_num);
 			if (err) {
 				ret = err;
+				printk("err %d from __extent_read_full_page\n", ret);
 			}
 		} else {
 			unlock_page(page);
@@ -2978,12 +2982,15 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 		submit_one_bio(READ, bio, mirror_num);
 
 	if (ret || !wait) {
+		if (ret)
+			printk("ret %d wait %d returning\n", ret, wait);
 		return ret;
 	}
 	for (i = start_i; i < num_pages; i++) {
 		page = extent_buffer_page(eb, i);
 		wait_on_page_locked(page);
 		if (!PageUptodate(page)) {
+			printk("page not uptodate after wait_on_page_locked\n");
 			ret = -EIO;
 		}
 	}

fs/btrfs/file.c

@@ -39,9 +39,10 @@
 #include "compat.h"
 
 
-static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
-				struct page **prepared_pages,
-				const char __user * buf)
+static int noinline btrfs_copy_from_user(loff_t pos, int num_pages,
+					 int write_bytes,
+					 struct page **prepared_pages,
+					 const char __user * buf)
 {
 	long page_fault = 0;
 	int i;
@@ -69,7 +70,7 @@ static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
 	return page_fault ? -EFAULT : 0;
 }
 
-static void btrfs_drop_pages(struct page **pages, size_t num_pages)
+static void noinline btrfs_drop_pages(struct page **pages, size_t num_pages)
 {
 	size_t i;
 	for (i = 0; i < num_pages; i++) {
@@ -359,7 +360,7 @@ static int noinline dirty_and_release_pages(struct btrfs_trans_handle *trans,
 	return err;
 }
 
-int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
+int noinline btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end)
 {
 	struct extent_map *em;
 	struct extent_map *split = NULL;
@@ -515,7 +516,7 @@ int btrfs_check_file(struct btrfs_root *root, struct inode *inode)
  * it is either truncated or split.  Anything entirely inside the range
  * is deleted from the tree.
  */
-int btrfs_drop_extents(struct btrfs_trans_handle *trans,
+int noinline btrfs_drop_extents(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *root, struct inode *inode,
 		       u64 start, u64 end, u64 inline_limit, u64 *hint_byte)
 {
@@ -785,7 +786,7 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans,
 /*
  * this gets pages into the page cache and locks them down
  */
-static int prepare_pages(struct btrfs_root *root, struct file *file,
+static int noinline prepare_pages(struct btrfs_root *root, struct file *file,
 			 struct page **pages, size_t num_pages,
 			 loff_t pos, unsigned long first_index,
 			 unsigned long last_index, size_t write_bytes)

fs/btrfs/volumes.c

@@ -94,8 +94,8 @@ int btrfs_cleanup_fs_uuids(void)
 	return 0;
 }
 
-static struct btrfs_device *__find_device(struct list_head *head, u64 devid,
-					  u8 *uuid)
+static noinline struct btrfs_device *__find_device(struct list_head *head,
+						   u64 devid, u8 *uuid)
 {
 	struct btrfs_device *dev;
 	struct list_head *cur;
@@ -110,7 +110,7 @@ static struct btrfs_device *__find_device(struct list_head *head, u64 devid,
 	return NULL;
 }
 
-static struct btrfs_fs_devices *find_fsid(u8 *fsid)
+static noinline struct btrfs_fs_devices *find_fsid(u8 *fsid)
 {
 	struct list_head *cur;
 	struct btrfs_fs_devices *fs_devices;
@@ -134,7 +134,7 @@ static struct btrfs_fs_devices *find_fsid(u8 *fsid)
  * the list if the block device is congested.  This way, multiple devices
  * can make progress from a single worker thread.
  */
-int run_scheduled_bios(struct btrfs_device *device)
+static int noinline run_scheduled_bios(struct btrfs_device *device)
 {
 	struct bio *pending;
 	struct backing_dev_info *bdi;
@@ -233,7 +233,7 @@ void pending_bios_fn(struct btrfs_work *work)
 	run_scheduled_bios(device);
 }
 
-static int device_list_add(const char *path,
+static noinline int device_list_add(const char *path,
 			   struct btrfs_super_block *disk_super,
 			   u64 devid, struct btrfs_fs_devices **fs_devices_ret)
 {
@@ -480,10 +480,10 @@ int btrfs_scan_one_device(const char *path, int flags, void *holder,
  * called very infrequently and that a given device has a small number
  * of extents
  */
-static int find_free_dev_extent(struct btrfs_trans_handle *trans,
-				struct btrfs_device *device,
-				struct btrfs_path *path,
-				u64 num_bytes, u64 *start)
+static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans,
+					 struct btrfs_device *device,
+					 struct btrfs_path *path,
+					 u64 num_bytes, u64 *start)
 {
 	struct btrfs_key key;
 	struct btrfs_root *root = device->dev_root;
@@ -645,7 +645,7 @@ int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
+int noinline btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
 			   struct btrfs_device *device,
 			   u64 chunk_tree, u64 chunk_objectid,
 			   u64 chunk_offset,
@@ -693,7 +693,8 @@ int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-static int find_next_chunk(struct btrfs_root *root, u64 objectid, u64 *offset)
+static noinline int find_next_chunk(struct btrfs_root *root,
+				    u64 objectid, u64 *offset)
 {
 	struct btrfs_path *path;
 	int ret;
@@ -735,8 +736,8 @@ static int find_next_chunk(struct btrfs_root *root, u64 objectid, u64 *offset)
 	return ret;
 }
 
-static int find_next_devid(struct btrfs_root *root, struct btrfs_path *path,
-			   u64 *objectid)
+static noinline int find_next_devid(struct btrfs_root *root,
+				    struct btrfs_path *path, u64 *objectid)
 {
 	int ret;
 	struct btrfs_key key;
@@ -1103,8 +1104,8 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 	goto out;
 }
 
-int btrfs_update_device(struct btrfs_trans_handle *trans,
-			struct btrfs_device *device)
+int noinline btrfs_update_device(struct btrfs_trans_handle *trans,
+				 struct btrfs_device *device)
 {
 	int ret;
 	struct btrfs_path *path;
@@ -1544,8 +1545,8 @@ int btrfs_add_system_chunk(struct btrfs_trans_handle *trans,
 	return 0;
 }
 
-static u64 chunk_bytes_by_type(u64 type, u64 calc_size, int num_stripes,
-			       int sub_stripes)
+static u64 noinline chunk_bytes_by_type(u64 type, u64 calc_size,
+					int num_stripes, int sub_stripes)
 {
 	if (type & (BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_DUP))
 		return calc_size;
@@ -2141,8 +2142,9 @@ struct async_sched {
  * This will add one bio to the pending list for a device and make sure
  * the work struct is scheduled.
  */
-int schedule_bio(struct btrfs_root *root, struct btrfs_device *device,
-		 int rw, struct bio *bio)
+static int noinline schedule_bio(struct btrfs_root *root,
+				 struct btrfs_device *device,
+				 int rw, struct bio *bio)
 {
 	int should_queue = 1;