Btrfs: deal with read errors on extent buffers differently

[linux-2.6-block.git] / fs / btrfs / disk-io.c

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 53c5ea7027998fa0e5aa3beb52c68578992086af..6107b69584135e82485a676ebe7771558818235e 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -360,9 +360,11 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                                          u64 start, u64 parent_transid)
 {
        struct extent_io_tree *io_tree;
+       int failed = 0;
        int ret;
        int num_copies = 0;
        int mirror_num = 0;
+       int failed_mirror = 0;
 
        clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
        io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
@@ -371,7 +373,7 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                                               WAIT_COMPLETE,
                                               btree_get_extent, mirror_num);
                if (!ret && !verify_parent_transid(io_tree, eb, parent_transid))
-                       return ret;
+                       break;
 
                /*
                 * This buffer's crc is fine, but its contents are corrupted, so
@@ -379,18 +381,31 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
                 * any less wrong.
                 */
                if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags))
-                       return ret;
+                       break;
+
+               if (!failed_mirror) {
+                       failed = 1;
+                       printk(KERN_ERR "failed mirror was %d\n", eb->failed_mirror);
+                       failed_mirror = eb->failed_mirror;
+               }
 
                num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
                                              eb->start, eb->len);
                if (num_copies == 1)
-                       return ret;
+                       break;
 
                mirror_num++;
+               if (mirror_num == failed_mirror)
+                       mirror_num++;
+
                if (mirror_num > num_copies)
-                       return ret;
+                       break;
        }
-       return -EIO;
+
+       if (failed && !ret)
+               repair_eb_io_failure(root, eb, failed_mirror);
+
+       return ret;
 }
 
 /*
@@ -575,6 +590,11 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
        if (!reads_done)
                goto err;
 
+       if (test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
+               ret = -EIO;
+               goto err;
+       }
+
        found_start = btrfs_header_bytenr(eb);
        if (found_start != eb->start) {
                printk_ratelimited(KERN_INFO "btrfs bad tree block start "
@@ -626,21 +646,16 @@ out:
        return ret;
 }
 
-static int btree_io_failed_hook(struct bio *failed_bio,
-                        struct page *page, u64 start, u64 end,
-                        int mirror_num, struct extent_state *state)
+static int btree_io_failed_hook(struct page *page, int failed_mirror)
 {
        struct extent_buffer *eb;
        struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 
        eb = (struct extent_buffer *)page->private;
-       if (page != eb->pages[0])
-               return -EIO;
-
-       if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
-               clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
+       set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+       eb->failed_mirror = failed_mirror;
+       if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags))
                btree_readahead_hook(root, eb, eb->start, -EIO);
-       }
        return -EIO;    /* we fixed nothing */
 }