android_kernel_samsung_sm8650/drivers/block/zram
Sergey Senozhatsky f635725c39 zram: do not waste zram_table_entry flags bits
zram_table_entry::flags stores object size in the lower bits and zram
pageflags in the upper bits.  However, for some reason, we use 24 lower
bits, while maximum zram object size is PAGE_SIZE, which requires
PAGE_SHIFT bits (up to 16 on arm64).  This wastes 24 - PAGE_SHIFT bits
that we can use for additional zram pageflags instead.

Also add a BUILD_BUG_ON() to alert us should we run out of bits in
zram_table_entry::flags.

Link: https://lkml.kernel.org/r/20220912152744.527438-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:09 -07:00
..
Kconfig zram: fix Kconfig dependency warning 2022-05-25 10:47:47 -07:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
zcomp.c zram: do not lookup algorithm in backends table 2022-07-03 18:08:50 -07:00
zcomp.h zram: Use local lock to protect per-CPU data 2020-05-28 10:31:10 +02:00
zram_drv.c zram: do not waste zram_table_entry flags bits 2022-10-03 14:03:09 -07:00
zram_drv.h zram: do not waste zram_table_entry flags bits 2022-10-03 14:03:09 -07:00