Commit 23cfbc6e authored by Takashi Iwai's avatar Takashi Iwai Committed by Greg Kroah-Hartman
Browse files

firmware: Add the support for ZSTD-compressed firmware files 

As the growing demand on ZSTD compressions, there have been requests
for the support of ZSTD-compressed firmware files, so here it is:
this patch extends the firmware loader code to allow loading ZSTD
files.  The implementation is fairly straightforward, it just adds a
ZSTD decompression routine for the file expander.  (And the code is
even simpler than XZ thanks to the ZSTD API that gives the original
decompressed size from the header.)

Link: https://lore.kernel.org/all/20210127154939.13288-1-tiwai@suse.de/


Tested-by: default avatarPiotr Gorski <lucjan.lucjanov@gmail.com>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20220421152908.4718-2-tiwai@suse.de


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ce522ba9

drivers/base/firmware_loader/Kconfig

+18 −6
Original line number Diff line number Diff line
@@ -159,21 +159,33 @@ config FW_LOADER_USER_HELPER_FALLBACK 


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).



	  Compressed firmware support does not apply to firmware images

	  that are built into the kernel image (CONFIG_EXTRA_FIRMWARE).



if FW_LOADER_COMPRESS

config FW_LOADER_COMPRESS_XZ

	bool "Enable XZ-compressed firmware support"

	select FW_LOADER_PAGED_BUF

	select XZ_DEC

	help

	  This option adds the support for XZ-compressed files.

	  The files have to be compressed with either none or crc32

	  integrity check type (pass "-C crc32" option to xz command).



config FW_LOADER_COMPRESS_ZSTD

	bool "Enable ZSTD-compressed firmware support"

	select ZSTD_DECOMPRESS

	help

	  This option adds the support for ZSTD-compressed files.



endif # FW_LOADER_COMPRESS



config FW_CACHE

	bool "Enable firmware caching during suspend"

	depends on PM_SLEEP

drivers/base/firmware_loader/main.c

+73 −3
Original line number Diff line number Diff line
@@ -35,6 +35,7 @@ 
#include <linux/syscore_ops.h>

#include <linux/reboot.h>

#include <linux/security.h>

#include <linux/zstd.h>

#include <linux/xz.h>



#include <generated/utsrelease.h>
@@ -304,10 +305,74 @@ int fw_map_paged_buf(struct fw_priv *fw_priv) 
}

#endif



/*

 * ZSTD-compressed firmware support

 */

#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD

static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,

			      size_t in_size, const void *in_buffer)

{

	size_t len, out_size, workspace_size;

	void *workspace, *out_buf;

	zstd_dctx *ctx;

	int err;



	if (fw_priv->allocated_size) {

		out_size = fw_priv->allocated_size;

		out_buf = fw_priv->data;

	} else {

		zstd_frame_header params;



		if (zstd_get_frame_header(&params, in_buffer, in_size) ||

		    params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {

			dev_dbg(dev, "%s: invalid zstd header\n", __func__);

			return -EINVAL;

		}

		out_size = params.frameContentSize;

		out_buf = vzalloc(out_size);

		if (!out_buf)

			return -ENOMEM;

	}



	workspace_size = zstd_dctx_workspace_bound();

	workspace = kvzalloc(workspace_size, GFP_KERNEL);

	if (!workspace) {

		err = -ENOMEM;

		goto error;

	}



	ctx = zstd_init_dctx(workspace, workspace_size);

	if (!ctx) {

		dev_dbg(dev, "%s: failed to initialize context\n", __func__);

		err = -EINVAL;

		goto error;

	}



	len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);

	if (zstd_is_error(len)) {

		dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,

			zstd_get_error_code(len));

		err = -EINVAL;

		goto error;

	}



	if (!fw_priv->allocated_size)

		fw_priv->data = out_buf;

	fw_priv->size = len;

	err = 0;



 error:

	kvfree(workspace);

	if (err && !fw_priv->allocated_size)

		vfree(out_buf);

	return err;

}

#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */



/*

 * XZ-compressed firmware support

 */

#ifdef CONFIG_FW_LOADER_COMPRESS

#ifdef CONFIG_FW_LOADER_COMPRESS_XZ

/* show an error and return the standard error code */

static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)

{
@@ -401,7 +466,7 @@ static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv, 
	else

		return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);

}

#endif /* CONFIG_FW_LOADER_COMPRESS */

#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */



/* direct firmware loading support */

static char fw_path_para[256];
@@ -757,7 +822,12 @@ _request_firmware(const struct firmware **firmware_p, const char *name, 
	if (!(opt_flags & FW_OPT_PARTIAL))

		nondirect = true;



#ifdef CONFIG_FW_LOADER_COMPRESS

#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD

	if (ret == -ENOENT && nondirect)

		ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",

						 fw_decompress_zstd);

#endif

#ifdef CONFIG_FW_LOADER_COMPRESS_XZ

	if (ret == -ENOENT && nondirect)

		ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",

						 fw_decompress_xz);