mirror of https://gitee.com/openkylin/linux.git
82fd7a8142
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> |
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| .. | ||
| builtin | ||
| Kconfig | ||
| Makefile | ||
| fallback.c | ||
| fallback.h | ||
| fallback_table.c | ||
| firmware.h | ||
| main.c | ||