linux/drivers/md/bitmap.c, branch v4.1

md/bitmap: remove rcu annotation from pointer arithmetic.

2015-05-20T23:14:41Z

Evaluating "&mddev->disks" is simple pointer arithmetic, so it does not need 'rcu' annotations - no dereferencing is happening. Also enhance the comment to explain that 'rdev' in that case is not actually a pointer to an rdev. Reported-by: Patrick Marlier Signed-off-by: NeilBrown

md-cluster: re-add capabilities

2015-04-21T21:59:39Z

When "re-add" is writted to /sys/block/mdXX/md/dev-YYY/state, the clustered md: 1. Sends RE_ADD message with the desc_nr. Nodes receiving the message clear the Faulty bit in their respective rdev->flags. 2. The node initiating re-add, gathers the bitmaps of all nodes and copies them into the local bitmap. It does not clear the bitmap from which it is copying. 3. Initiating node schedules a md recovery to sync the devices. Signed-off-by: Guoqing Jiang Signed-off-by: Goldwyn Rodrigues Signed-off-by: NeilBrown

md: Fix bitmap offset calculations

2015-03-25T02:07:55Z

The calculations of bitmap offset is incorrect with respect to bits to bytes conversion. Also, remove an irrelevant duplicate message. Signed-off-by: Goldwyn Rodrigues Signed-off-by: NeilBrown

md/bitmap: use sector_div for sector_t divisions

2015-03-04T02:08:16Z

neilb: modified to not corrupt ->resync_max_sectors. sector_div usage fixed by Guoqing Jiang Signed-off-by: Stephen Rothwell Signed-off-by: NeilBrown

md/bitmap: fix incorrect DIV_ROUND_UP usage.

2015-03-04T01:54:29Z

DIV_ROUTND_UP doesn't work on "long long", - and it should be sector_t anyway. Signed-off-by: NeilBrown

Copy set bits from another slot

2015-02-23T15:59:05Z

bitmap_copy_from_slot reads the bitmap from the slot mentioned. It then copies the set bits to the node local bitmap. This is helper function for the resync operation on node failure. bitmap_set_memory_bits() currently assumes it is only run at startup and that they bitmap is currently empty. So if it finds that a region is already marked as dirty, it won't mark it dirty again. Change bitmap_set_memory_bits() to always set the NEEDED_MASK bit if 'needed' is set. Signed-off-by: Goldwyn Rodrigues

bitmap_create returns bitmap pointer

2015-02-23T15:57:57Z

This is done to have multiple bitmaps open at the same time. Signed-off-by: Goldwyn Rodrigues

Use separate bitmaps for each nodes in the cluster

2015-02-23T13:30:11Z

On-disk format: 0 4k 8k 12k ------------------------------------------------------------------- | idle | md super | bm super [0] + bits | | bm bits[0, contd] | bm super[1] + bits | bm bits[1, contd] | | bm super[2] + bits | bm bits [2, contd] | bm super[3] + bits | | bm bits [3, contd] | | | Bitmap super has a field nodes, which defines the maximum number of nodes the device can use. While reading the bitmap super, if the cluster finds out that the number of nodes is > 0: 1. Requests the md-cluster module. 2. Calls md_cluster_ops->join(), which sets up clustering such as joining DLM lockspace. Since the first time, the first bitmap is read. After the call to the cluster_setup, the bitmap offset is adjusted and the superblock is re-read. This also ensures the bitmap is read the bitmap lock (when bitmap lock is introduced in later patches) Questions: 1. cluster name is repeated in all bitmap supers. Is that okay? Signed-off-by: Goldwyn Rodrigues

Add node recovery callbacks

2015-02-23T13:30:11Z

DLM offers callbacks when a node fails and the lock remastery is performed: 1. recover_prep: called when DLM discovers a node is down 2. recover_slot: called when DLM identifies the node and recovery can start 3. recover_done: called when all nodes have completed recover_slot recover_slot() and recover_done() are also called when the node joins initially in order to inform the node with its slot number. These slot numbers start from one, so we deduct one to make it start with zero which the cluster-md code uses. Signed-off-by: Goldwyn Rodrigues

Introduce md_cluster_info

2015-02-23T13:28:42Z

md_cluster_info stores the cluster information in the MD device. The join() is called when mddev detects it is a clustered device. The main responsibilities are: 1. Setup a DLM lockspace 2. Setup all initial locks such as super block locks and bitmap lock (will come later) The leave() clears up the lockspace and all the locks held. Signed-off-by: Goldwyn Rodrigues