Forwarded: OCFS2 fix test

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Subject: OCFS2 fix test
Author: swilczek.lx@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
master

diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index e85b1ccf81be..136aaaae27f3 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -821,6 +821,19 @@ static int ocfs2_acquire_dquot(struct dquot *dquot)
     trace_ocfs2_acquire_dquot(from_kqid(&init_user_ns, dquot->dq_id),
                   type);
     mutex_lock(&dquot->dq_lock);
+    /*
+     * Extend global quota file before acquiring global qf lock to avoid
+     * lock inversion with sb_internal (via ocfs2_start_trans).
+     */
+    if (need_alloc) {
+        WARN_ON(journal_current_handle());
+        status = ocfs2_extend_no_holes(gqinode, NULL,
+            i_size_read(gqinode) + (need_alloc << sb->s_blocksize_bits),
+            i_size_read(gqinode));
+        if (status < 0)
+            goto out;
+    }
+
     /*
      * We need an exclusive lock, because we're going to update use count
      * and instantiate possibly new dquot structure
@@ -843,19 +856,8 @@ static int ocfs2_acquire_dquot(struct dquot *dquot)
     OCFS2_DQUOT(dquot)->dq_use_count++;
     OCFS2_DQUOT(dquot)->dq_origspace = dquot->dq_dqb.dqb_curspace;
     OCFS2_DQUOT(dquot)->dq_originodes = dquot->dq_dqb.dqb_curinodes;
-    if (!dquot->dq_off) {    /* No real quota entry? */
+    if (!dquot->dq_off)    /* No real quota entry? */
         ex = 1;
-        /*
-         * Add blocks to quota file before we start a transaction since
-         * locking allocators ranks above a transaction start
-         */
-        WARN_ON(journal_current_handle());
-        status = ocfs2_extend_no_holes(gqinode, NULL,
-            i_size_read(gqinode) + (need_alloc << sb->s_blocksize_bits),
-            i_size_read(gqinode));
-        if (status < 0)
-            goto out_dq;
-    }

     handle = ocfs2_start_trans(osb,
                    ocfs2_calc_global_qinit_credits(sb, type));