VServer 1.9.2 (patch-2.6.8.1-vs1.9.2.diff)

[linux-2.6.git] / include / linux / quotaops.h

diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index 9db474d..acc926c 100644 (file)
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -69,9 +69,22 @@ static __inline__ void DQUOT_INIT(struct inode *inode)
 /* The same as with DQUOT_INIT */
 static __inline__ void DQUOT_DROP(struct inode *inode)
 {
-       if (IS_QUOTAINIT(inode)) {
-               BUG_ON(!inode->i_sb);
-               inode->i_sb->dq_op->drop(inode);        /* Ops must be set when there's any quota... */
+       /* Here we can get arbitrary inode from clear_inode() so we have
+        * to be careful. OTOH we don't need locking as quota operations
+        * are allowed to change only at mount time */
+       if (!IS_NOQUOTA(inode) && inode->i_sb && inode->i_sb->dq_op
+           && inode->i_sb->dq_op->drop) {
+               int cnt;
+               /* Test before calling to rule out calls from proc and such
+                 * where we are not allowed to block. Note that this is
+                * actually reliable test even without the lock - the caller
+                * must assure that nobody can come after the DQUOT_DROP and
+                * add quota pointers back anyway */
+               for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+                       if (inode->i_dquot[cnt] != NODQUOT)
+                               break;
+               if (cnt < MAXQUOTAS)
+                       inode->i_sb->dq_op->drop(inode);
        }
 }