Btrfs: Handle write errors on raid1 and raid10
When duplicate copies exist, writes are allowed to fail to one of those
copies. This changeset includes a few changes that allow the FS to
continue even when some IOs fail.
It also adds verification of the parent generation number for btree blocks.
This generation is stored in the pointer to a block, and it ensures
that missed writes to are detected.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 289d71d..02e571e 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -379,7 +379,7 @@
cur = btrfs_find_tree_block(root, blocknr, blocksize);
if (cur)
- uptodate = btrfs_buffer_uptodate(cur);
+ uptodate = btrfs_buffer_uptodate(cur, gen);
else
uptodate = 0;
if (!cur || !uptodate) {
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index edee7a4..574b124 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -205,6 +205,33 @@
return 0;
}
+static int verify_parent_transid(struct extent_io_tree *io_tree,
+ struct extent_buffer *eb, u64 parent_transid)
+{
+ int ret;
+
+ if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
+ return 0;
+
+ lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS);
+ if (extent_buffer_uptodate(io_tree, eb) &&
+ btrfs_header_generation(eb) == parent_transid) {
+ ret = 0;
+ goto out;
+ }
+ printk("parent transid verify failed on %llu wanted %llu found %llu\n",
+ (unsigned long long)eb->start,
+ (unsigned long long)parent_transid,
+ (unsigned long long)btrfs_header_generation(eb));
+ ret = 1;
+out:
+ clear_extent_buffer_uptodate(io_tree, eb);
+ unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
+ GFP_NOFS);
+ return ret;
+
+}
+
static int btree_read_extent_buffer_pages(struct btrfs_root *root,
struct extent_buffer *eb,
u64 start, u64 parent_transid)
@@ -218,7 +245,8 @@
while (1) {
ret = read_extent_buffer_pages(io_tree, eb, start, 1,
btree_get_extent, mirror_num);
- if (!ret)
+ if (!ret &&
+ !verify_parent_transid(io_tree, eb, parent_transid))
return ret;
num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
@@ -330,6 +358,13 @@
ret = -EIO;
goto err;
}
+ if (memcmp_extent_buffer(eb, root->fs_info->fsid,
+ (unsigned long)btrfs_header_fsid(eb),
+ BTRFS_FSID_SIZE)) {
+ printk("bad fsid on block %Lu\n", eb->start);
+ ret = -EIO;
+ goto err;
+ }
found_level = btrfs_header_level(eb);
ret = csum_tree_block(root, eb, 1);
@@ -1363,7 +1398,9 @@
"I/O error on %s\n",
bdevname(bh->b_bdev, b));
}
- set_buffer_write_io_error(bh);
+ /* note, we dont' set_buffer_write_io_error because we have
+ * our own ways of dealing with the IO errors
+ */
clear_buffer_uptodate(bh);
}
unlock_buffer(bh);
@@ -1459,7 +1496,8 @@
ret = submit_bh(WRITE, bh);
BUG_ON(ret);
wait_on_buffer(bh);
- BUG_ON(!buffer_uptodate(bh));
+ if (!buffer_uptodate(bh))
+ total_errors++;
} else {
total_errors++;
}
@@ -1607,10 +1645,18 @@
return 0;
}
-int btrfs_buffer_uptodate(struct extent_buffer *buf)
+int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
{
+ int ret;
struct inode *btree_inode = buf->first_page->mapping->host;
- return extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
+
+ ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
+ if (!ret)
+ return ret;
+
+ ret = verify_parent_transid(&BTRFS_I(btree_inode)->io_tree, buf,
+ parent_transid);
+ return !ret;
}
int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index e29c895..30d1ed2 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -56,7 +56,7 @@
void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr);
int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root);
void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
-int btrfs_buffer_uptodate(struct extent_buffer *buf);
+int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid);
int btrfs_set_buffer_uptodate(struct extent_buffer *buf);
int wait_on_tree_block_writeback(struct btrfs_root *root,
struct extent_buffer *buf);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index db07dde..605018c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1366,7 +1366,7 @@
if (!pending) {
buf = btrfs_find_tree_block(root, bytenr, num_bytes);
if (buf) {
- if (btrfs_buffer_uptodate(buf)) {
+ if (btrfs_buffer_uptodate(buf, 0)) {
u64 transid =
root->fs_info->running_transaction->transid;
u64 header_transid =
@@ -2151,7 +2151,7 @@
continue;
}
next = btrfs_find_tree_block(root, bytenr, blocksize);
- if (!next || !btrfs_buffer_uptodate(next)) {
+ if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
free_extent_buffer(next);
reada_walk_down(root, cur, path->slots[*level]);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index dd403b4..2a3624a 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1366,7 +1366,7 @@
unsigned int bytes_done, int err)
#endif
{
- const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
+ int uptodate = err == 0;
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
struct extent_state *state = bio->bi_private;
struct extent_io_tree *tree = state->tree;
@@ -1375,6 +1375,7 @@
u64 end;
u64 cur;
int whole_page;
+ int ret;
unsigned long flags;
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
@@ -1395,17 +1396,30 @@
if (--bvec >= bio->bi_io_vec)
prefetchw(&bvec->bv_page->flags);
+ if (tree->ops && tree->ops->writepage_end_io_hook) {
+ ret = tree->ops->writepage_end_io_hook(page, start,
+ end, state);
+ if (ret)
+ uptodate = 0;
+ }
+
+ if (!uptodate && tree->ops &&
+ tree->ops->writepage_io_failed_hook) {
+ ret = tree->ops->writepage_io_failed_hook(bio, page,
+ start, end, state);
+ if (ret == 0) {
+ state = NULL;
+ uptodate = (err == 0);
+ continue;
+ }
+ }
+
if (!uptodate) {
clear_extent_uptodate(tree, start, end, GFP_ATOMIC);
ClearPageUptodate(page);
SetPageError(page);
}
- if (tree->ops && tree->ops->writepage_end_io_hook) {
- tree->ops->writepage_end_io_hook(page, start, end,
- state);
- }
-
/*
* bios can get merged in funny ways, and so we need to
* be careful with the state variable. We know the
@@ -2073,9 +2087,9 @@
} else {
ret = 0;
}
- if (ret)
+ if (ret) {
SetPageError(page);
- else {
+ } else {
unsigned long max_nr = end_index + 1;
set_range_writeback(tree, cur, cur + iosize - 1);
if (!PageWriteback(page)) {
@@ -2948,6 +2962,25 @@
}
EXPORT_SYMBOL(set_extent_buffer_dirty);
+int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
+ struct extent_buffer *eb)
+{
+ unsigned long i;
+ struct page *page;
+ unsigned long num_pages;
+
+ num_pages = num_extent_pages(eb->start, eb->len);
+ eb->flags &= ~EXTENT_UPTODATE;
+
+ clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
+ GFP_NOFS);
+ for (i = 0; i < num_pages; i++) {
+ page = extent_buffer_page(eb, i);
+ ClearPageUptodate(page);
+ }
+ return 0;
+}
+
int set_extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb)
{
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index e483461..f1960da 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -36,9 +36,12 @@
int (*readpage_io_failed_hook)(struct bio *bio, struct page *page,
u64 start, u64 end,
struct extent_state *state);
+ int (*writepage_io_failed_hook)(struct bio *bio, struct page *page,
+ u64 start, u64 end,
+ struct extent_state *state);
int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
struct extent_state *state);
- void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
+ int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
struct extent_state *state);
int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
unsigned long old, unsigned long bits);
@@ -212,6 +215,8 @@
struct extent_buffer *eb);
int set_extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb);
+int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
+ struct extent_buffer *eb);
int extent_buffer_uptodate(struct extent_io_tree *tree,
struct extent_buffer *eb);
int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a492fd2..08760ff 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -430,9 +430,9 @@
int last_mirror;
};
-int btrfs_readpage_io_failed_hook(struct bio *failed_bio,
- struct page *page, u64 start, u64 end,
- struct extent_state *state)
+int btrfs_io_failed_hook(struct bio *failed_bio,
+ struct page *page, u64 start, u64 end,
+ struct extent_state *state)
{
struct io_failure_record *failrec = NULL;
u64 private;
@@ -443,6 +443,7 @@
struct bio *bio;
int num_copies;
int ret;
+ int rw;
u64 logical;
ret = get_state_private(failure_tree, start, &private);
@@ -505,7 +506,41 @@
bio->bi_bdev = failed_bio->bi_bdev;
bio->bi_size = 0;
bio_add_page(bio, page, failrec->len, start - page_offset(page));
- btrfs_submit_bio_hook(inode, READ, bio, failrec->last_mirror);
+ if (failed_bio->bi_rw & (1 << BIO_RW))
+ rw = WRITE;
+ else
+ rw = READ;
+
+ BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
+ failrec->last_mirror);
+ return 0;
+}
+
+int btrfs_clean_io_failures(struct inode *inode, u64 start)
+{
+ u64 private;
+ u64 private_failure;
+ struct io_failure_record *failure;
+ int ret;
+
+ private = 0;
+ if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
+ (u64)-1, 1, EXTENT_DIRTY)) {
+ ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
+ start, &private_failure);
+ if (ret == 0) {
+ failure = (struct io_failure_record *)(unsigned long)
+ private_failure;
+ set_state_private(&BTRFS_I(inode)->io_failure_tree,
+ failure->start, 0);
+ clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
+ failure->start,
+ failure->start + failure->len - 1,
+ EXTENT_DIRTY | EXTENT_LOCKED,
+ GFP_NOFS);
+ kfree(failure);
+ }
+ }
return 0;
}
@@ -547,26 +582,7 @@
/* if the io failure tree for this inode is non-empty,
* check to see if we've recovered from a failed IO
*/
- private = 0;
- if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
- (u64)-1, 1, EXTENT_DIRTY)) {
- u64 private_failure;
- struct io_failure_record *failure;
- ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
- start, &private_failure);
- if (ret == 0) {
- failure = (struct io_failure_record *)(unsigned long)
- private_failure;
- set_state_private(&BTRFS_I(inode)->io_failure_tree,
- failure->start, 0);
- clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
- failure->start,
- failure->start + failure->len - 1,
- EXTENT_DIRTY | EXTENT_LOCKED,
- GFP_NOFS);
- kfree(failure);
- }
- }
+ btrfs_clean_io_failures(inode, start);
return 0;
zeroit:
@@ -3657,7 +3673,7 @@
.merge_bio_hook = btrfs_merge_bio_hook,
.readpage_io_hook = btrfs_readpage_io_hook,
.readpage_end_io_hook = btrfs_readpage_end_io_hook,
- .readpage_io_failed_hook = btrfs_readpage_io_failed_hook,
+ .readpage_io_failed_hook = btrfs_io_failed_hook,
.set_bit_hook = btrfs_set_bit_hook,
.clear_bit_hook = btrfs_clear_bit_hook,
};
diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index 5085e9e..c02e2bf 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -51,6 +51,7 @@
struct extent_buffer *next;
struct extent_buffer *cur;
u64 bytenr;
+ u64 ptr_gen;
int ret = 0;
int is_extent = 0;
@@ -93,11 +94,12 @@
break;
}
bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
+ ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
if (cache_only) {
next = btrfs_find_tree_block(root, bytenr,
btrfs_level_size(root, *level - 1));
- if (!next || !btrfs_buffer_uptodate(next) ||
+ if (!next || !btrfs_buffer_uptodate(next, ptr_gen) ||
!btrfs_buffer_defrag(next)) {
free_extent_buffer(next);
path->slots[*level]++;
@@ -106,8 +108,7 @@
} else {
next = read_tree_block(root, bytenr,
btrfs_level_size(root, *level - 1),
- btrfs_node_ptr_generation(cur,
- path->slots[*level]));
+ ptr_gen);
}
ret = btrfs_cow_block(trans, root, next, path->nodes[*level],
path->slots[*level], &next);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index b5d7bd1..5fc7fb4 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1807,14 +1807,19 @@
if (atomic_dec_and_test(&multi->stripes_pending)) {
bio->bi_private = multi->private;
bio->bi_end_io = multi->end_io;
-
/* only send an error to the higher layers if it is
* beyond the tolerance of the multi-bio
*/
- if (atomic_read(&multi->error) > multi->max_errors)
+ if (atomic_read(&multi->error) > multi->max_errors) {
err = -EIO;
- else
+ } else if (err) {
+ /*
+ * this bio is actually up to date, we didn't
+ * go over the max number of errors
+ */
+ set_bit(BIO_UPTODATE, &bio->bi_flags);
err = 0;
+ }
kfree(multi);
#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)