From fa90243e20eeef91eda5a5bb249bed05066852e3 Mon Sep 17 00:00:00 2001 From: Pranith Kumar K Date: Sat, 14 Apr 2012 14:33:53 +0530 Subject: cluster/afr: Enforce order in pre/post op The xattrop order in pre/post op on all the subvols is client-0, client-1... client-n where n is (replica-count - 1). This order can lead to invalid split-brains if the brick dies in the middle of xattrops. Example: transaction completed pre-op, so on all the subvolumes xattrs have '1' changelog. Now post-op is sent to both the subvols. On subvol-0 change-log of client-0 is decremented to 0, before decrementing change-log of client-1 to 0 the brick dies. This change-log status on subvol-0 gives the meaning that a change is done on subvol-0 successfully but on subvol-1 it failed. Which is not what happened. Changes done when the subvol-0 was down will lead to pending change-log on subvol-1 for subvol-0. Which is correct. When the subvol-0 is brought back up, the change-log will be in split-brain state even when it is not a legitimate split-brain. If the brick dies in the middle of xattrops it should remain fool. Pre-op should perform xattrop of the local change-log first and post-op should perform xattrop of the local change-log last. In case of optimistic changelogs txn_changelog should be done last on local if it succeeds, first if it fails. Change-Id: Ib6eeb20cdc49b0b1fd2f454f25a9c8e08388c6e7 BUG: 765194 Signed-off-by: Pranith Kumar K Reviewed-on: http://review.gluster.com/3226 Tested-by: Gluster Build System Reviewed-by: Anand Avati --- xlators/cluster/afr/src/afr-transaction.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'xlators/cluster/afr/src/afr-transaction.h') diff --git a/xlators/cluster/afr/src/afr-transaction.h b/xlators/cluster/afr/src/afr-transaction.h index 965ee673..d19d16fb 100644 --- a/xlators/cluster/afr/src/afr-transaction.h +++ b/xlators/cluster/afr/src/afr-transaction.h @@ -11,6 +11,11 @@ #ifndef __TRANSACTION_H__ #define __TRANSACTION_H__ +typedef enum { + LOCAL_FIRST = 1, + LOCAL_LAST = 2 +} afr_xattrop_type_t; + void afr_transaction_fop_failed (call_frame_t *frame, xlator_t *this, int child_index); @@ -24,5 +29,6 @@ afr_transaction (call_frame_t *frame, xlator_t *this, afr_transaction_type type) afr_fd_ctx_t * afr_fd_ctx_get (fd_t *fd, xlator_t *this); int -afr_set_pending_dict (afr_private_t *priv, dict_t *xattr, int32_t **pending); +afr_set_pending_dict (afr_private_t *priv, dict_t *xattr, int32_t **pending, + int child, afr_xattrop_type_t op); #endif /* __TRANSACTION_H__ */ -- cgit