ocfs2: Add ->set_lvb callback in dlmglue

This allows a lock type to set the value block before downconvert.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
This commit is contained in:
Mark Fasheh 2006-09-13 21:21:52 -07:00
parent 16d5b9567a
commit 5ef0d4ea08

View File

@ -130,6 +130,17 @@ struct ocfs2_lock_res_ops {
*/
int (*check_downconvert)(struct ocfs2_lock_res *, int);
/*
* Allows a lock type to populate the lock value block. This
* is called on downconvert, and when we drop a lock.
*
* Locks that want to use this should set LOCK_TYPE_USES_LVB
* in the flags field.
*
* Called with the lockres spinlock held.
*/
void (*set_lvb)(struct ocfs2_lock_res *);
/*
* LOCK_TYPE_* flags which describe the specific requirements
* of a lock type. Descriptions of each individual flag follow.
@ -148,7 +159,8 @@ struct ocfs2_lock_res_ops {
#define LOCK_TYPE_REQUIRES_REFRESH 0x1
/*
* Indicate that a lock type makes use of the lock value block.
* Indicate that a lock type makes use of the lock value block. The
* ->set_lvb lock type callback must be defined.
*/
#define LOCK_TYPE_USES_LVB 0x2
@ -2629,6 +2641,7 @@ static int ocfs2_generic_unblock_lock(struct ocfs2_super *osb,
int blocking;
int new_level;
int ret = 0;
int set_lvb = 0;
mlog_entry_void();
@ -2703,9 +2716,23 @@ recheck:
downconvert:
ctl->requeue = 0;
if (lockres->l_ops->flags & LOCK_TYPE_USES_LVB) {
if (lockres->l_level == LKM_EXMODE)
set_lvb = 1;
/*
* We only set the lvb if the lock has been fully
* refreshed - otherwise we risk setting stale
* data. Otherwise, there's no need to actually clear
* out the lvb here as it's value is still valid.
*/
if (set_lvb && !(lockres->l_flags & OCFS2_LOCK_NEEDS_REFRESH))
lockres->l_ops->set_lvb(lockres);
}
ocfs2_prepare_downconvert(lockres, new_level);
spin_unlock_irqrestore(&lockres->l_lock, flags);
ret = ocfs2_downconvert_lock(osb, lockres, new_level, 0);
ret = ocfs2_downconvert_lock(osb, lockres, new_level, set_lvb);
leave:
mlog_exit(ret);
return ret;