BMC/Intel-BMC/linux.git/drivers/md/md-cluster.c, branch dev-4.6

md-cluster: fix missing memory free

2016-01-25T02:13:18+00:00

There are several places we allocate dlm_lock_resource, but not free it. leave() need free a lock resource too (from Guoqing) Cc: Goldwyn Rodrigues Cc: Guoqing Jiang Cc: NeilBrown Signed-off-by: Shaohua Li

md-cluster: update comments for MD_CLUSTER_SEND_LOCKED_ALREADY

2016-01-06T00:39:21+00:00

1. fix unbalanced parentheses. 2. add more description about that MD_CLUSTER_SEND_LOCKED_ALREADY will be cleared after set it in add_new_disk. Signed-off-by: Guoqing Jiang Signed-off-by: NeilBrown

md-cluster: Protect communication with mutexes

2016-01-06T00:39:17+00:00

Communication can happen through multiple threads. It is possible that one thread steps over another threads sequence. So, we use mutexes to protect both the send and receive sequences. Send communication is locked through state bit, MD_CLUSTER_SEND_LOCK. Communication is locked with bit manipulation in order to allow "lock and hold" for the add operation. In case of an add operation, if the lock is held, MD_CLUSTER_SEND_LOCKED_ALREADY is set. When md_update_sb() calls metadata_update_start(), it checks (in a single statement to avoid races), if the communication is already locked. If yes, it merely returns zero, else it locks the token lockresource. Signed-off-by: Goldwyn Rodrigues Signed-off-by: NeilBrown

md-cluster: Defer MD reloading to mddev->thread

2016-01-06T00:39:10+00:00

Reloading of superblock must be performed under reconfig_mutex. However, this cannot be done with md_reload_sb because it would deadlock with the message DLM lock. So, we defer it in md_check_recovery() which is executed by mddev->thread. This introduces a new flag, MD_RELOAD_SB, which if set, will reload the superblock. And good_device_nr is also added to 'struct mddev' which is used to get the num of the good device within cluster raid. Signed-off-by: Goldwyn Rodrigues Signed-off-by: Guoqing Jiang Signed-off-by: NeilBrown

md-cluster: append some actions when change bitmap from clustered to none

2016-01-06T00:38:57+00:00

For clustered raid, we need to do extra actions when change bitmap to none. 1. check if all the bitmap lock could be get or not, if yes then we can continue the change since cluster raid is only active in current node. Otherwise return fail and unlock the related bitmap locks 2. set nodes to 0 and then leave cluster environment. 3. release other nodes's bitmap lock. Signed-off-by: Guoqing Jiang Signed-off-by: NeilBrown

md-cluster: Fix the remove sequence with the new MD reload code

2016-01-06T00:38:42+00:00

The remove disk message does not need metadata_update_start(), but can be an independent message. Signed-off-by: Goldwyn Rodrigues Signed-off-by: Guoqing Jiang Signed-off-by: NeilBrown

md-cluster: remove a disk asynchronously from cluster environment

2016-01-06T00:38:36+00:00

For cluster raid, if one disk couldn't be reach in one node, then other nodes would receive the REMOVE message for the disk. In receiving node, we can't call md_kick_rdev_from_array to remove the disk from array synchronously since the disk might still be busy in this node. So let's set a ClusterRemove flag on the disk, then let the thread to do the removal job eventually. Signed-off-by: Guoqing Jiang Signed-off-by: Goldwyn Rodrigues Signed-off-by: NeilBrown

md-cluster: Avoid the resync ping-pong

2016-01-06T00:38:27+00:00

If a RESYNCING message with (0,0) has been sent before, do not send it again. This avoids a resync ping pong between the nodes. We read the bitmap lockresource's LVB to figure out the previous value of the RESYNCING message. Signed-off-by: Goldwyn Rodrigues Signed-off-by: NeilBrown

md-cluster: remove mddev arg from add_resync_info()

2015-10-24T06:16:18+00:00

The arg isn't used, so its presence is only confusing. Signed-off-by: NeilBrown

md-cluster: don't cast void pointers when assigning them.

2015-10-24T06:16:18+00:00

It is common practice in the kernel to leave out this case. It isn't needed and adds little if any value. Signed-off-by: NeilBrown