diff options
| author | Takashi Iwai <tiwai@suse.de> | 2019-06-11 15:26:25 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-18 10:11:22 +0300 |
| commit | 82fd7a8142a10b8eb41313074b3859d82c0857dc (patch) | |
| tree | c98ad021f2d262809d9155ad443c2ea009b78a4e /drivers/base/firmware_loader/Kconfig | |
| parent | 5342e7093ff298d9cbd40f9342b607adb02b2dd0 (diff) | |
| download | linux-82fd7a8142a10b8eb41313074b3859d82c0857dc.tar.xz | |
firmware: Add support for loading compressed files
This patch adds the support for loading compressed firmware files.
The primary motivation is to reduce the storage size; e.g. currently
the files in /lib/firmware on my machine counts up to 419MB, while
they can be reduced to 130MB by file compression.
The patch introduces a new kconfig option CONFIG_FW_LOADER_COMPRESS.
Even with this option set, the firmware loader still tries to load the
original firmware file as-is at first, but then falls back to the file
with ".xz" extension when it's not found, and the decompressed file
content is returned to the caller of request_firmware(). So, no
change is needed for the rest.
Currently only XZ format is supported. A caveat is that the kernel XZ
helper code supports only CRC32 (or none) integrity check type, so
you'll have to compress the files via xz -C crc32 option.
Since we can't determine the expanded size immediately from an XZ
file, the patch re-uses the paged buffer that was used for the
user-mode fallback; it puts the decompressed content page, which are
vmapped at the end. The paged buffer code is conditionally built with
a new Kconfig that is selected automatically.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base/firmware_loader/Kconfig')
| -rw-r--r-- | drivers/base/firmware_loader/Kconfig | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig index 38f2da6f5c2b..3f9e274e2ed3 100644 --- a/drivers/base/firmware_loader/Kconfig +++ b/drivers/base/firmware_loader/Kconfig @@ -26,6 +26,9 @@ config FW_LOADER if FW_LOADER +config FW_LOADER_PAGED_BUF + bool + config EXTRA_FIRMWARE string "Build named firmware blobs into the kernel binary" help @@ -67,6 +70,7 @@ config EXTRA_FIRMWARE_DIR config FW_LOADER_USER_HELPER bool "Enable the firmware sysfs fallback mechanism" + select FW_LOADER_PAGED_BUF help This option enables a sysfs loading facility to enable firmware loading to the kernel through userspace as a fallback mechanism @@ -151,5 +155,19 @@ config FW_LOADER_USER_HELPER_FALLBACK If you are unsure about this, say N here. +config FW_LOADER_COMPRESS + bool "Enable compressed firmware support" + select FW_LOADER_PAGED_BUF + select XZ_DEC + help + This option enables the support for loading compressed firmware + files. The caller of firmware API receives the decompressed file + content. The compressed file is loaded as a fallback, only after + loading the raw file failed at first. + + Currently only XZ-compressed files are supported, and they have to + be compressed with either none or crc32 integrity check type (pass + "-C crc32" option to xz command). + endif # FW_LOADER endmenu |