ceph: don't call truncate_pagecache in ceph_writepages_start
truncate_pagecache() may decrease inode's reference. This can cause
deadlock if inode's last reference is dropped and iput_final() wants
to evict the inode. (evict() calls inode_wait_for_writeback(), which
waits for ceph_writepages_start() to return).
The fix is use work thead to truncate dirty pages. Also add 'forced
umount' check to ceph_update_writeable_page(), which prevents new
pages getting dirty.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index f474184..d52e3bc 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -715,8 +715,11 @@
(wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
if (ACCESS_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
- pr_warn("writepage_start %p on forced umount\n", inode);
- truncate_pagecache(inode, 0);
+ if (ci->i_wrbuffer_ref > 0) {
+ pr_warn_ratelimited(
+ "writepage_start %p %lld forced umount\n",
+ inode, ceph_ino(inode));
+ }
mapping_set_error(mapping, -EIO);
return -EIO; /* we're in a forced umount, don't write! */
}
@@ -1127,6 +1130,7 @@
struct page *page)
{
struct inode *inode = file_inode(file);
+ struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_inode_info *ci = ceph_inode(inode);
loff_t page_off = pos & PAGE_MASK;
int pos_in_page = pos & ~PAGE_MASK;
@@ -1135,6 +1139,12 @@
int r;
struct ceph_snap_context *snapc, *oldest;
+ if (ACCESS_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
+ dout(" page %p forced umount\n", page);
+ unlock_page(page);
+ return -EIO;
+ }
+
retry_locked:
/* writepages currently holds page lock, but if we change that later, */
wait_on_page_writeback(page);