[PATCH] ocfs2: fix orphan recovery deadlock
Orphan dir recovery can deadlock with another process in
ocfs2_delete_inode() in some corner cases. Fix this by tracking recovery
state more closely and allowing it to handle inode wipes which might
deadlock.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 8122489..315472a 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -41,6 +41,7 @@
#include "dlmglue.h"
#include "extent_map.h"
#include "file.h"
+#include "heartbeat.h"
#include "inode.h"
#include "journal.h"
#include "namei.h"
@@ -544,6 +545,42 @@
return status;
}
+/*
+ * Serialize with orphan dir recovery. If the process doing
+ * recovery on this orphan dir does an iget() with the dir
+ * i_mutex held, we'll deadlock here. Instead we detect this
+ * and exit early - recovery will wipe this inode for us.
+ */
+static int ocfs2_check_orphan_recovery_state(struct ocfs2_super *osb,
+ int slot)
+{
+ int ret = 0;
+
+ spin_lock(&osb->osb_lock);
+ if (ocfs2_node_map_test_bit(osb, &osb->osb_recovering_orphan_dirs, slot)) {
+ mlog(0, "Recovery is happening on orphan dir %d, will skip "
+ "this inode\n", slot);
+ ret = -EDEADLK;
+ goto out;
+ }
+ /* This signals to the orphan recovery process that it should
+ * wait for us to handle the wipe. */
+ osb->osb_orphan_wipes[slot]++;
+out:
+ spin_unlock(&osb->osb_lock);
+ return ret;
+}
+
+static void ocfs2_signal_wipe_completion(struct ocfs2_super *osb,
+ int slot)
+{
+ spin_lock(&osb->osb_lock);
+ osb->osb_orphan_wipes[slot]--;
+ spin_unlock(&osb->osb_lock);
+
+ wake_up(&osb->osb_wipe_event);
+}
+
static int ocfs2_wipe_inode(struct inode *inode,
struct buffer_head *di_bh)
{
@@ -555,6 +592,11 @@
/* We've already voted on this so it should be readonly - no
* spinlock needed. */
orphaned_slot = OCFS2_I(inode)->ip_orphaned_slot;
+
+ status = ocfs2_check_orphan_recovery_state(osb, orphaned_slot);
+ if (status)
+ return status;
+
orphan_dir_inode = ocfs2_get_system_file_inode(osb,
ORPHAN_DIR_SYSTEM_INODE,
orphaned_slot);
@@ -597,6 +639,7 @@
brelse(orphan_dir_bh);
bail:
iput(orphan_dir_inode);
+ ocfs2_signal_wipe_completion(osb, orphaned_slot);
return status;
}
@@ -822,7 +865,8 @@
status = ocfs2_wipe_inode(inode, di_bh);
if (status < 0) {
- mlog_errno(status);
+ if (status != -EDEADLK)
+ mlog_errno(status);
goto bail_unlock_inode;
}