linux-stable.git/drivers/md/bitmap.c, branch v4.1.41

md/bitmap: don't pass -1 to bitmap_storage_alloc.

2015-10-22T21:43:26+00:00

commit da6fb7a9e5bd6f04f7e15070f630bdf1ea502841 upstream.

Passing -1 to bitmap_storage_alloc() causes page->index to be set to
-1, which is quite problematic.

So only pass ->cluster_slot if mddev_is_clustered().

Fixes: b97e92574c0b ("Use separate bitmaps for each nodes in the cluster")
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md: Skip cluster setup for dm-raid

2015-08-03T16:29:13+00:00

commit d3b178adb3a3adf54ecf77758138b654c3ee7f09 upstream.

There is a bug that the bitmap superblock isn't initialised properly for
dm-raid, so a new field can have garbage in new fields.
(dm-raid does initialisation in the kernel - md initialised the
 superblock in mdadm).

This means that for dm-raid we cannot currently trust the new ->nodes
field. So:
 - use __GFP_ZERO to initialise the superblock properly for all new
    arrays
 - initialise all fields in bitmap_info in bitmap_new_disk_sb
 - ignore ->nodes for dm arrays (yes, this is a hack)

This bug exposes dm-raid to bug in the (still experimental) md-cluster
code, so it is suitable for -stable.  It does cause crashes.

References: https://bugzilla.kernel.org/show_bug.cgi?id=100491
Signed-off-By: Goldwyn Rodrigues 
Signed-off-by: NeilBrown 
Signed-off-by: Greg Kroah-Hartman

md/bitmap: remove rcu annotation from pointer arithmetic.

2015-05-20T23:14:41+00:00

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

2015-04-21T21:59:39+00:00

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

2015-03-25T02:07:55+00:00

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

2015-03-04T02:08:16+00:00

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.

2015-03-04T01:54:29+00:00

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

2015-02-23T15:59:05+00:00

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

2015-02-23T15:57:57+00:00

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

2015-02-23T13:30:11+00:00

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