ocfs2: fix race between dio and recover orphan

During direct io the inode will be added to orphan first and then
deleted from orphan.  There is a race window that the orphan entry will
be deleted twice and thus trigger the BUG when validating
OCFS2_DIO_ORPHANED_FL in ocfs2_del_inode_from_orphan.

ocfs2_direct_IO_write
    ...
    ocfs2_add_inode_to_orphan
    >>>>>>>> race window.
             1) another node may rm the file and then down, this node
             take care of orphan recovery and clear flag
             OCFS2_DIO_ORPHANED_FL.
             2) since rw lock is unlocked, it may race with another
             orphan recovery and append dio.
    ocfs2_del_inode_from_orphan

So take inode mutex lock when recovering orphans and make rw unlock at the
end of aio write in case of append dio.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Weiwei Wang <wangww631@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 0f5fd9d..1e88ff4 100644 (file)
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -627,10 +627,13 @@ static void ocfs2_dio_end_io(struct kiocb *iocb,
                mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
        }
 
-       ocfs2_iocb_clear_rw_locked(iocb);
+       /* Let rw unlock to be done later to protect append direct io write */
+       if (offset + bytes <= i_size_read(inode)) {
+               ocfs2_iocb_clear_rw_locked(iocb);
 
-       level = ocfs2_iocb_rw_locked_level(iocb);
-       ocfs2_rw_unlock(inode, level);
+               level = ocfs2_iocb_rw_locked_level(iocb);
+               ocfs2_rw_unlock(inode, level);
+       }
 }
 
 static int ocfs2_releasepage(struct page *page, gfp_t wait)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 2eb1136..5d384a6 100644 (file)
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2416,7 +2416,7 @@ relock:
        }
 
 no_sync:
-       if (unaligned_dio) {
+       if (unaligned_dio && ocfs2_iocb_is_unaligned_aio(iocb)) {
                ocfs2_iocb_clear_unaligned_aio(iocb);
                mutex_unlock(&OCFS2_I(inode)->ip_unaligned_aio);
        }

diff --git a/fs/ocfs2/inode.h b/fs/ocfs2/inode.h
index 5e86b24..ca3431e 100644 (file)
--- a/fs/ocfs2/inode.h
+++ b/fs/ocfs2/inode.h
@@ -81,8 +81,6 @@ struct ocfs2_inode_info
        tid_t i_sync_tid;
        tid_t i_datasync_tid;
 
-       wait_queue_head_t append_dio_wq;
-
        struct dquot *i_dquot[MAXQUOTAS];
 };
 

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 7c099f7..5e56268 100644 (file)
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -2170,6 +2170,7 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                iter = oi->ip_next_orphan;
                oi->ip_next_orphan = NULL;
 
+               mutex_lock(&inode->i_mutex);
                ret = ocfs2_rw_lock(inode, 1);
                if (ret < 0) {
                        mlog_errno(ret);
@@ -2206,17 +2207,16 @@ static int ocfs2_recover_orphans(struct ocfs2_super *osb,
                        ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);
                        if (ret)
                                mlog_errno(ret);
-
-                       wake_up(&OCFS2_I(inode)->append_dio_wq);
                } /* else if ORPHAN_NO_NEED_TRUNCATE, do nothing */
 unlock_inode:
                ocfs2_inode_unlock(inode, 1);
+               brelse(di_bh);
+               di_bh = NULL;
 unlock_rw:
                ocfs2_rw_unlock(inode, 1);
 next:
+               mutex_unlock(&inode->i_mutex);
                iput(inode);
-               brelse(di_bh);
-               di_bh = NULL;
                inode = iter;
        }
 

diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 948681e..e9ea7f2 100644 (file)
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -2601,27 +2601,6 @@ leave:
        return status;
 }
 
-static int ocfs2_dio_orphan_recovered(struct inode *inode)
-{
-       int ret;
-       struct buffer_head *di_bh = NULL;
-       struct ocfs2_dinode *di = NULL;
-
-       ret = ocfs2_inode_lock(inode, &di_bh, 1);
-       if (ret < 0) {
-               mlog_errno(ret);
-               return 0;
-       }
-
-       di = (struct ocfs2_dinode *) di_bh->b_data;
-       ret = !(di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL));
-       ocfs2_inode_unlock(inode, 1);
-       brelse(di_bh);
-
-       return ret;
-}
-
-#define OCFS2_DIO_ORPHANED_FL_CHECK_INTERVAL 10000
 int ocfs2_add_inode_to_orphan(struct ocfs2_super *osb,
        struct inode *inode)
 {
@@ -2633,7 +2612,6 @@ int ocfs2_add_inode_to_orphan(struct ocfs2_super *osb,
        handle_t *handle = NULL;
        struct ocfs2_dinode *di = NULL;
 
-restart:
        status = ocfs2_inode_lock(inode, &di_bh, 1);
        if (status < 0) {
                mlog_errno(status);
@@ -2643,15 +2621,21 @@ restart:
        di = (struct ocfs2_dinode *) di_bh->b_data;
        /*
         * Another append dio crashed?
-        * If so, wait for recovery first.
+        * If so, manually recover it first.
         */
        if (unlikely(di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL))) {
-               ocfs2_inode_unlock(inode, 1);
-               brelse(di_bh);
-               wait_event_interruptible_timeout(OCFS2_I(inode)->append_dio_wq,
-                               ocfs2_dio_orphan_recovered(inode),
-                               msecs_to_jiffies(OCFS2_DIO_ORPHANED_FL_CHECK_INTERVAL));
-               goto restart;
+               status = ocfs2_truncate_file(inode, di_bh, i_size_read(inode));
+               if (status < 0) {
+                       if (status != -ENOSPC)
+                               mlog_errno(status);
+                       goto bail_unlock_inode;
+               }
+
+               status = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);
+               if (status < 0) {
+                       mlog_errno(status);
+                       goto bail_unlock_inode;
+               }
        }
 
        status = ocfs2_prepare_orphan_dir(osb, &orphan_dir_inode,

diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 403c566..4474ef2 100644 (file)
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1746,8 +1746,6 @@ static void ocfs2_inode_init_once(void *data)
        ocfs2_lock_res_init_once(&oi->ip_inode_lockres);
        ocfs2_lock_res_init_once(&oi->ip_open_lockres);
 
-       init_waitqueue_head(&oi->append_dio_wq);
-
        ocfs2_metadata_cache_init(INODE_CACHE(&oi->vfs_inode),
                                  &ocfs2_inode_caching_ops);