linux-toradex.git/include/linux/device-mapper.h, branch Colibri_T30_LinuxImageV2.1Beta2_20140206

dm crypt: always disable discard_zeroes_data

2011-09-25T22:26:21+00:00

If optional discard support in dm-crypt is enabled, discards requests
bypass the crypt queue and blocks of the underlying device are discarded.
For the read path, discarded blocks are handled the same as normal
ciphertext blocks, thus decrypted.

So if the underlying device announces discarded regions return zeroes,
dm-crypt must disable this flag because after decryption there is just
random noise instead of zeroes.

Signed-off-by: Milan Broz 
Signed-off-by: Alasdair G Kergon

dm table: share target argument parsing functions

2011-08-02T11:32:04+00:00

Move multipath target argument parsing code into dm-table so other
targets can share it.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm table: allow targets to support discards internally

2011-05-29T11:52:55+00:00

Permit a target to support discards regardless of whether or not all its
underlying devices do.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

md/dm - remove remains of plug_fn callback.

2011-04-18T08:25:41+00:00

Now that unplugging is done differently, the unplug_fn callback is
never called, so it can be completely discarded.

Signed-off-by: NeilBrown

block: remove per-queue plugging

2011-03-10T07:52:07+00:00

Code has been converted over to the new explicit on-stack plugging,
and delay users have been converted to use the new API for that.
So lets kill off the old plugging along with aops->sync_page().

Signed-off-by: Jens Axboe

dm: per target unplug callback support

2011-01-13T20:00:02+00:00

Add per-target unplug callback support.

Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown 
Signed-off-by: Jonathan Brassow 
Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm: introduce target callbacks and congestion callback

2011-01-13T20:00:01+00:00

DM currently implements congestion checking by checking on congestion
in each component device.  For raid456 we need to also check if the
stripe cache is congested.

Add per-target congestion checker callback support.

Extending the target_callbacks structure with additional callback
functions allows for establishing multiple callbacks per-target (a
callback is also needed for unplug).

Cc: linux-raid@vger.kernel.org
Signed-off-by: NeilBrown 
Signed-off-by: Jonathan Brassow 
Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm: factor out max_io_len_target_boundary

2010-08-12T03:14:10+00:00

Split max_io_len_target_boundary out of max_io_len so that the discard
support can make use of it without duplicating max_io_len code.

Avoiding max_io_len's split_io logic enables DM's discard support to
submit the entire discard request to a target.  But discards must still
be split on target boundaries.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon

dm: linear support discard

2010-08-12T03:14:08+00:00

Allow discards to be passed through to linear mappings if at least one
underlying device supports it.  Discards will be forwarded only to
devices that support them.

A target that supports discards should set num_discard_requests to
indicate how many times each discard request must be submitted to it.

Verify table's underlying devices support discards prior to setting the
associated DM device as capable of discards (via QUEUE_FLAG_DISCARD).

Signed-off-by: Mike Snitzer 
Signed-off-by: Mikulas Patocka 
Reviewed-by: Joe Thornber 
Signed-off-by: Alasdair G Kergon

dm: rename map_info flush_request to target_request_nr

2010-08-12T03:14:04+00:00

'target_request_nr' is a more generic name that reflects the fact that
it will be used for both flush and discard support.

Signed-off-by: Mike Snitzer 
Signed-off-by: Alasdair G Kergon