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.)
Tested-by: Piotr Gorski lucjan.lucjanov@gmail.com Link: https://lore.kernel.org/all/20210127154939.13288-1-tiwai@suse.de/ Signed-off-by: Takashi Iwai tiwai@suse.de --- drivers/base/firmware_loader/Kconfig | 24 ++++++--- drivers/base/firmware_loader/main.c | 76 ++++++++++++++++++++++++++-- 2 files changed, 91 insertions(+), 9 deletions(-)
diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig index 38f3b66bf52b..08bb50451a96 100644 --- a/drivers/base/firmware_loader/Kconfig +++ b/drivers/base/firmware_loader/Kconfig @@ -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 diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 94d1789a233e..74830aeec7f6 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -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(¶ms, 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);