linux/Documentation/device-mapper
Patrik Torstensson 67628da0e2 BACKPORT: dm verity: add 'check_at_most_once' option to only validate hashes once
This allows platforms that are CPU/memory contrained to verify data
blocks only the first time they are read from the data device, rather
than every time.  As such, it provides a reduced level of security
because only offline tampering of the data device's content will be
detected, not online tampering.

Hash blocks are still verified each time they are read from the hash
device, since verification of hash blocks is less performance critical
than data blocks, and a hash block will not be verified any more after
all the data blocks it covers have been verified anyway.

This option introduces a bitset that is used to check if a block has
been validated before or not.  A block can be validated more than once
as there is no thread protection for the bitset.

These changes were developed and tested on entry-level Android Go
devices.

(change to use vzalloc/vfree)
(change per_bio_data_size variable)

Bug: 72664474
Change-Id: I2db2db26c7897c78407789de2cc4cff3587c84bb
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
(cherry picked from commit 843f38d382)
Signed-off-by: Patrik Torstensson <totte@google.com>
2018-05-20 16:40:16 +05:30
..
boot.txt CHROMIUM: dm: boot time specification of dm= 2016-08-18 18:56:03 +05:30
cache-policies.txt dm cache: switch the "default" cache replacement policy from mq to smq 2015-06-17 12:40:38 -04:00
cache.txt dm cache: display 'needs_check' in status if it is set 2015-07-16 10:23:50 -04:00
delay.txt dm delay: document that offsets are specified in sectors 2015-10-31 19:06:05 -04:00
dm-crypt.txt dm crypt: update URLs to new cryptsetup project page 2015-04-15 12:10:24 -04:00
dm-flakey.txt dm flakey: add corrupt_bio_byte feature 2011-08-02 12:32:06 +01:00
dm-io.txt
dm-log.txt dm log userspace: fix comment hyphens 2011-10-31 20:21:22 +00:00
dm-queue-length.txt
dm-raid.txt dm raid: document RAID 4/5/6 discard support 2015-08-31 15:05:31 -04:00
dm-service-time.txt Fix common misspellings 2011-03-31 11:26:23 -03:00
dm-uevent.txt
era.txt dm: add era target 2014-03-27 16:56:23 -04:00
kcopyd.txt
linear.txt
log-writes.txt dm: add log writes target 2015-04-15 12:10:24 -04:00
persistent-data.txt Documentation: Fix multiple typo in Documentation 2012-03-07 16:08:24 +01:00
snapshot.txt dm snapshot: add new persistent store option to support overflow 2015-10-09 16:57:03 -04:00
statistics.txt dm stats: report precise_timestamps and histogram in @stats_list output 2015-08-18 17:20:03 -04:00
striped.txt dm stripe: support for non power of 2 chunksize 2012-07-27 15:08:01 +01:00
switch.txt dm switch: fix Documentation to use plain text 2015-03-31 12:03:49 -04:00
thin-provisioning.txt dm thin: display 'needs_check' in status if it is set 2015-07-16 10:23:50 -04:00
verity.txt BACKPORT: dm verity: add 'check_at_most_once' option to only validate hashes once 2018-05-20 16:40:16 +05:30
zero.txt