xavi/android_kernel_m2note/drivers/md/Kconfig, branch o-8.1

ANDROID: dm verity: add minimum prefetch size

2018-01-06T16:15:19+00:00

- For device like eMMC, it gives better performance to read more hash blocks at a time. - For android, set it to default 128. For other devices, set it to 1 which is the same as now. - saved boot-up time by 300ms in tested device bug: 32246564 Cc: Sami Tolvanen Signed-off-by: Keun-young Park

ANDROID: dm: Add android verity target

2017-12-27T18:08:51+00:00

This device-mapper target is virtually a VERITY target. This target is setup by reading the metadata contents piggybacked to the actual data blocks in the block device. The signature of the metadata contents are verified against the key included in the system keyring. Upon success, the underlying verity target is setup. BUG: 27175947 Change-Id: I7e99644a0960ac8279f02c0158ed20999510ea97 Signed-off-by: Badhri Jagan Sridharan

dm verity: add support for forward error correction

2017-12-27T18:08:50+00:00

Add support for correcting corrupted blocks using Reed-Solomon. This code uses RS(255, N) interleaved across data and hash blocks. Each error-correcting block covers N bytes evenly distributed across the combined total data, so that each byte is a maximum distance away from the others. This makes it possible to recover from several consecutive corrupted blocks with relatively small space overhead. In addition, using verity hashes to locate erasures nearly doubles the effectiveness of error correction. Being able to detect corrupted blocks also improves performance, because only corrupted blocks need to corrected. For a 2 GiB partition, RS(255, 253) (two parity bytes for each 253-byte block) can correct up to 16 MiB of consecutive corrupted blocks if erasures can be located, and 8 MiB if they cannot, with 16 MiB space overhead. Bug: 21893453 Change-Id: Ib0372f49f45127e33bfe6b7182b0d608f56f3c7e Signed-off-by: Sami Tolvanen Signed-off-by: Mike Snitzer (cherry picked from commit a431c56bf1764448c12fd2d545b15466d552460c)

first commit

2016-08-15T02:19:42+00:00