ceph: handle interrupted ceph_writepage()
writepage() can be interrupted when it's called by direct memory
reclaimer (the direct memory relaimer is killed). To avoid lossing
data, we redirty the page.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 4aa8e37..080a9ca 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -544,11 +544,21 @@
truncate_seq, truncate_size,
&inode->i_mtime, &page, 1);
if (err < 0) {
- dout("writepage setting page/mapping error %d %p\n", err, page);
+ struct writeback_control tmp_wbc;
+ if (!wbc)
+ wbc = &tmp_wbc;
+ if (err == -ERESTARTSYS) {
+ /* killed by SIGKILL */
+ dout("writepage interrupted page %p\n", page);
+ redirty_page_for_writepage(wbc, page);
+ end_page_writeback(page);
+ goto out;
+ }
+ dout("writepage setting page/mapping error %d %p\n",
+ err, page);
SetPageError(page);
mapping_set_error(&inode->i_data, err);
- if (wbc)
- wbc->pages_skipped++;
+ wbc->pages_skipped++;
} else {
dout("writepage cleaned page %p\n", page);
err = 0; /* vfs expects us to return 0 */
@@ -569,12 +579,16 @@
BUG_ON(!inode);
ihold(inode);
err = writepage_nounlock(page, wbc);
+ if (err == -ERESTARTSYS) {
+ /* direct memory reclaimer was killed by SIGKILL. return 0
+ * to prevent caller from setting mapping/page error */
+ err = 0;
+ }
unlock_page(page);
iput(inode);
return err;
}
-
/*
* lame release_pages helper. release_pages() isn't exported to
* modules.