lustre/mdc: comments on LOOKUP and PERM lock

Add more comments for MDS_INODELOCK_PERM and
MDS_INODELOCK_LOOKUP

Signed-off-by: wang di <di.wang@intel.com>
Reviewed-on: http://review.whamcloud.com/7937
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-3240
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
wang di 2014-02-28 21:16:33 -05:00 committed by Greg Kroah-Hartman
parent 588de43a9b
commit fe4c58af2f
2 changed files with 21 additions and 6 deletions

View File

@ -2116,12 +2116,24 @@ extern void lustre_swab_generic_32s (__u32 *val);
#define DISP_OPEN_LEASE 0x04000000
/* INODE LOCK PARTS */
#define MDS_INODELOCK_LOOKUP 0x000001 /* dentry, mode, owner, group */
#define MDS_INODELOCK_UPDATE 0x000002 /* size, links, timestamps */
#define MDS_INODELOCK_OPEN 0x000004 /* For opened files */
#define MDS_INODELOCK_LAYOUT 0x000008 /* for layout */
#define MDS_INODELOCK_PERM 0x000010 /* for permission */
#define MDS_INODELOCK_XATTR 0x000020 /* extended attributes */
#define MDS_INODELOCK_LOOKUP 0x000001 /* For namespace, dentry etc, and also
* was used to protect permission (mode,
* owner, group etc) before 2.4. */
#define MDS_INODELOCK_UPDATE 0x000002 /* size, links, timestamps */
#define MDS_INODELOCK_OPEN 0x000004 /* For opened files */
#define MDS_INODELOCK_LAYOUT 0x000008 /* for layout */
/* The PERM bit is added int 2.4, and it is used to protect permission(mode,
* owner, group, acl etc), so to separate the permission from LOOKUP lock.
* Because for remote directories(in DNE), these locks will be granted by
* different MDTs(different ldlm namespace).
*
* For local directory, MDT will always grant UPDATE_LOCK|PERM_LOCK together.
* For Remote directory, the master MDT, where the remote directory is, will
* grant UPDATE_LOCK|PERM_LOCK, and the remote MDT, where the name entry is,
* will grant LOOKUP_LOCK. */
#define MDS_INODELOCK_PERM 0x000010
#define MDS_INODELOCK_XATTR 0x000020 /* extended attributes */
#define MDS_INODELOCK_MAXSHIFT 5
/* This FULL lock is useful to take on unlink sort of operations */

View File

@ -1072,6 +1072,9 @@ int mdc_revalidate_lock(struct obd_export *exp, struct lookup_intent *it,
* locks, there's no easy way to match all of them here,
* so an extra RPC would be performed to fetch all
* of those bits at once for now. */
/* For new MDTs(> 2.4), UPDATE|PERM should be enough,
* but for old MDTs (< 2.4), permission is covered
* by LOOKUP lock, so it needs to match all bits here.*/
policy.l_inodebits.bits = MDS_INODELOCK_UPDATE |
MDS_INODELOCK_LOOKUP |
MDS_INODELOCK_PERM;