From: Fan Yong <fan.yong@xxxxxxxxx> Since all the LOV_MAGIC_* definitions have the same postfix values break that value out into its own definition. With this we can check whether the magic's postfix match the LOV_MAGIC_MAGIC or not: if yes, then it is quite possible that the clients has encountered an newer LOV magic. This extra information can let us handle those cases more gracefully. Signed-off-by: Fan Yong <fan.yong@xxxxxxxxx> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4941 Reviewed-on: http://review.whamcloud.com/10045 Reviewed-by: Andreas Dilger <andreas.dilger@xxxxxxxxx> Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx> Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx> --- .../lustre/lustre/include/lustre/lustre_idl.h | 20 +++++++++++++++----- 1 files changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h index d3a9db9..3444add 100644 --- a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h +++ b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h @@ -1478,11 +1478,21 @@ enum obdo_flags { OBD_FL_LOCAL_MASK = 0xF0000000, }; -#define LOV_MAGIC_V1 0x0BD10BD0 -#define LOV_MAGIC LOV_MAGIC_V1 -#define LOV_MAGIC_JOIN_V1 0x0BD20BD0 -#define LOV_MAGIC_V3 0x0BD30BD0 -#define LOV_MAGIC_MIGRATE 0x0BD40BD0 +/* + * All LOV EA magics should have the same postfix, if some new version + * Lustre instroduces new LOV EA magic, then when down-grade to an old + * Lustre, even though the old version system does not recognizes such + * new magic, it still can distinguish the corrupted cases by checking + * the magic's postfix. + */ +#define LOV_MAGIC_MAGIC 0x0BD0 +#define LOV_MAGIC_MASK 0xFFFF + +#define LOV_MAGIC_V1 (0x0BD10000 | LOV_MAGIC_MAGIC) +#define LOV_MAGIC_JOIN_V1 (0x0BD20000 | LOV_MAGIC_MAGIC) +#define LOV_MAGIC_V3 (0x0BD30000 | LOV_MAGIC_MAGIC) +#define LOV_MAGIC_MIGRATE (0x0BD40000 | LOV_MAGIC_MAGIC) +#define LOV_MAGIC LOV_MAGIC_V1 /* * magic for fully defined striping -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
