[LU-8842] Possible incorrect handling of IT_OPEN in mdc_enqueue

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.10.0
• Labels: patch
• Severity: 3
• Assignee: WC Triage
• Reporter: Patrick Farrell

Description

The patch at:
http://review.whamcloud.com/#/c/10205/3

Changes handling of IT_OPEN in mdc_enqueue:

	if (it != NULL) {
		LASSERT(policy == NULL);

		saved_flags |= LDLM_FL_HAS_INTENT;
		if (it->it_op & (IT_OPEN | IT_UNLINK | IT_GETATTR | IT_READDIR))
			policy = &update_policy;
		else if (it->it_op & IT_LAYOUT)
			policy = &layout_policy;
		else if (it->it_op & (IT_GETXATTR | IT_SETXATTR))
			policy = &getxattr_policy;
		else
			policy = &lookup_policy;
	}

Previously, IT_OPEN was not special cased, and so used the "lookup_policy".

This means instead of using MDS_INODELOCK_LOOKUP for the inodebits, it uses MDS_INODELOCK_UPDATE.

I am not aware of any bugs this causes, but John Hammond confirmed to me this was a mistake, so I'm going to push a patch to revert that part of the change. (I found this while looking in to an issue, but this turned out not to be the cause of that issue.)