#include "ordered-data.h"
#include "transaction.h"
#include "backref.h"
+#include "extent_io.h"
/*
* This is only the first step towards a full-features scrub. It reads all
static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx)
{
- struct page *page;
+ struct page *page = NULL;
unsigned long index;
struct scrub_fixup_nodatasum *fixup = ctx;
int ret;
- int corrected;
+ int corrected = 0;
struct btrfs_key key;
- struct inode *inode;
+ struct inode *inode = NULL;
u64 end = offset + PAGE_SIZE - 1;
struct btrfs_root *local_root;
if (IS_ERR(inode))
return PTR_ERR(inode);
- ret = set_extent_bit(&BTRFS_I(inode)->io_tree, offset, end,
- EXTENT_DAMAGED, 0, NULL, NULL, GFP_NOFS);
-
- /* set_extent_bit should either succeed or give proper error */
- WARN_ON(ret > 0);
- if (ret)
- return ret < 0 ? ret : -EFAULT;
-
index = offset >> PAGE_CACHE_SHIFT;
page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
- if (!page)
- return -ENOMEM;
+ if (!page) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ if (PageUptodate(page)) {
+ struct btrfs_mapping_tree *map_tree;
+ if (PageDirty(page)) {
+ /*
+ * we need to write the data to the defect sector. the
+ * data that was in that sector is not in memory,
+ * because the page was modified. we must not write the
+ * modified page to that sector.
+ *
+ * TODO: what could be done here: wait for the delalloc
+ * runner to write out that page (might involve
+ * COW) and see whether the sector is still
+ * referenced afterwards.
+ *
+ * For the meantime, we'll treat this error
+ * incorrectable, although there is a chance that a
+ * later scrub will find the bad sector again and that
+ * there's no dirty page in memory, then.
+ */
+ ret = -EIO;
+ goto out;
+ }
+ map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree;
+ ret = repair_io_failure(map_tree, offset, PAGE_SIZE,
+ fixup->logical, page,
+ fixup->mirror_num);
+ unlock_page(page);
+ corrected = !ret;
+ } else {
+ /*
+ * we need to get good data first. the general readpage path
+ * will call repair_io_failure for us, we just have to make
+ * sure we read the bad mirror.
+ */
+ ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
+ EXTENT_DAMAGED, GFP_NOFS);
+ if (ret) {
+ /* set_extent_bits should give proper error */
+ WARN_ON(ret > 0);
+ if (ret > 0)
+ ret = -EFAULT;
+ goto out;
+ }
- ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
- btrfs_get_extent, fixup->mirror_num);
- wait_on_page_locked(page);
- corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset, end,
- EXTENT_DAMAGED, 0, NULL);
+ ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
+ btrfs_get_extent,
+ fixup->mirror_num);
+ wait_on_page_locked(page);
- if (corrected)
- WARN_ON(!PageUptodate(page));
- else
- clear_extent_bit(&BTRFS_I(inode)->io_tree, offset, end,
- EXTENT_DAMAGED, 0, 0, NULL, GFP_NOFS);
+ corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset,
+ end, EXTENT_DAMAGED, 0, NULL);
+ if (!corrected)
+ clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
+ EXTENT_DAMAGED, GFP_NOFS);
+ }
- put_page(page);
- iput(inode);
+out:
+ if (page)
+ put_page(page);
+ if (inode)
+ iput(inode);
if (ret < 0)
return ret;