diff options
Diffstat (limited to 'drivers/block/zram/Kconfig')
| -rw-r--r-- | drivers/block/zram/Kconfig | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/block/zram/Kconfig b/drivers/block/zram/Kconfig new file mode 100644 index 000000000..402b7b175 --- /dev/null +++ b/drivers/block/zram/Kconfig @@ -0,0 +1,147 @@ +# SPDX-License-Identifier: GPL-2.0 +config ZRAM + tristate "Compressed RAM block device support" + depends on BLOCK && SYSFS && MMU + select ZSMALLOC + help + Creates virtual block devices called /dev/zramX (X = 0, 1, ...). + Pages written to these disks are compressed and stored in memory + itself. These disks allow very fast I/O and compression provides + good amounts of memory savings. + + It has several use cases, for example: /tmp storage, use as swap + disks and maybe many more. + + See Documentation/admin-guide/blockdev/zram.rst for more information. + +config ZRAM_BACKEND_LZ4 + bool "lz4 compression support" + depends on ZRAM + select LZ4_COMPRESS + select LZ4_DECOMPRESS + +config ZRAM_BACKEND_LZ4HC + bool "lz4hc compression support" + depends on ZRAM + select LZ4HC_COMPRESS + select LZ4_DECOMPRESS + +config ZRAM_BACKEND_ZSTD + bool "zstd compression support" + depends on ZRAM + select ZSTD_COMPRESS + select ZSTD_DECOMPRESS + +config ZRAM_BACKEND_DEFLATE + bool "deflate compression support" + depends on ZRAM + select ZLIB_DEFLATE + select ZLIB_INFLATE + +config ZRAM_BACKEND_842 + bool "842 compression support" + depends on ZRAM + select 842_COMPRESS + select 842_DECOMPRESS + +config ZRAM_BACKEND_FORCE_LZO + depends on ZRAM + def_bool !ZRAM_BACKEND_LZ4 && !ZRAM_BACKEND_LZ4HC && \ + !ZRAM_BACKEND_ZSTD && !ZRAM_BACKEND_DEFLATE && \ + !ZRAM_BACKEND_842 + +config ZRAM_BACKEND_LZO + bool "lzo and lzo-rle compression support" if !ZRAM_BACKEND_FORCE_LZO + depends on ZRAM + default ZRAM_BACKEND_FORCE_LZO + select LZO_COMPRESS + select LZO_DECOMPRESS + +choice + prompt "Default zram compressor" + default ZRAM_DEF_COMP_LZORLE + depends on ZRAM + +config ZRAM_DEF_COMP_LZORLE + bool "lzo-rle" + depends on ZRAM_BACKEND_LZO + +config ZRAM_DEF_COMP_LZO + bool "lzo" + depends on ZRAM_BACKEND_LZO + +config ZRAM_DEF_COMP_LZ4 + bool "lz4" + depends on ZRAM_BACKEND_LZ4 + +config ZRAM_DEF_COMP_LZ4HC + bool "lz4hc" + depends on ZRAM_BACKEND_LZ4HC + +config ZRAM_DEF_COMP_ZSTD + bool "zstd" + depends on ZRAM_BACKEND_ZSTD + +config ZRAM_DEF_COMP_DEFLATE + bool "deflate" + depends on ZRAM_BACKEND_DEFLATE + +config ZRAM_DEF_COMP_842 + bool "842" + depends on ZRAM_BACKEND_842 + +endchoice + +config ZRAM_DEF_COMP + string + depends on ZRAM + default "lzo-rle" if ZRAM_DEF_COMP_LZORLE + default "lzo" if ZRAM_DEF_COMP_LZO + default "lz4" if ZRAM_DEF_COMP_LZ4 + default "lz4hc" if ZRAM_DEF_COMP_LZ4HC + default "zstd" if ZRAM_DEF_COMP_ZSTD + default "deflate" if ZRAM_DEF_COMP_DEFLATE + default "842" if ZRAM_DEF_COMP_842 + default "unset-value" + +config ZRAM_WRITEBACK + bool "Write back incompressible or idle page to backing device" + depends on ZRAM + help + This lets zram entries (incompressible or idle pages) be written + back to a backing device, helping save memory. + For this feature, admin should set up backing device via + /sys/block/zramX/backing_dev. + + With /sys/block/zramX/{idle,writeback}, application could ask + idle page's writeback to the backing device to save in memory. + + See Documentation/admin-guide/blockdev/zram.rst for more information. + +config ZRAM_TRACK_ENTRY_ACTIME + bool "Track access time of zram entries" + depends on ZRAM + help + With this feature zram tracks access time of every stored + entry (page), which can be used for a more fine grained IDLE + pages writeback. + +config ZRAM_MEMORY_TRACKING + bool "Track zRam block status" + depends on ZRAM && DEBUG_FS + select ZRAM_TRACK_ENTRY_ACTIME + help + With this feature, admin can track the state of allocated blocks + of zRAM. Admin could see the information via + /sys/kernel/debug/zram/zramX/block_state. + + See Documentation/admin-guide/blockdev/zram.rst for more information. + +config ZRAM_MULTI_COMP + bool "Enable multiple compression streams" + depends on ZRAM + help + This will enable multi-compression streams, so that ZRAM can + re-compress pages using a potentially slower but more effective + compression algorithm. Note, that IDLE page recompression + requires ZRAM_TRACK_ENTRY_ACTIME. |