Jonathan Earl Brassow 2b34836c61 A misunderstanding of the return value of 'dm_bit' has been causing a data ... corruption bug in cmirror. 'dm_bit' is only ever used as a boolean operation within LVM, but it can return a range of values. If the bit is set, a power of 2 is returned. If the bit is unset, 0 is returned. 'log_test_bit' (a function in the cluster mirror log daemon code) has switched to using the dm bit operations in rhel6. There are two places in the daemon code where 'log_test_bit' is not used merely as a boolean, but rather the return value is used as the return value for the log functions 'is_clean' and 'in_sync' - having assumed that 'dm_bit' was returning 0 or 1 only. One place the 'in_sync' function is utilized is in 'dm_rh_get_state' - a function that informs the mirroring code how to treat I/O and which devices to read/write from. 'dm_rh_get_state' was checking if the return value of 'in_sync' was 1 to determine if the region was DM_RH_CLEAN. Since 'dm_bit' (and by extension 'log_test_bit' and 'in_sync') was returning powers of 2, DM_RH_CLEAN was rarely being reported as it should have been. Thinking the region was out-of-sync, the mirroring code would write only to the primary device. When the primary device was failed, all of those writes were lost - leaving the entire mirror corrupted.		2010-08-04 18:18:18 +00:00
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clvmd	Use void parameter for function definition.	2010-08-03 13:06:35 +00:00
cmirrord	A misunderstanding of the return value of 'dm_bit' has been causing a data	2010-08-04 18:18:18 +00:00
dmeventd	Add dm_create_lockfile to libdm to handle pidfiles for all daemons.	2010-07-13 13:51:01 +00:00
Makefile.in	Use vpath instead of VPATH.	2010-04-09 21:34:25 +00:00