Now with zstd compressed kernel & initrd upstream, we would rather compress everything with one type of compressor, so I added support for zstd compressed firmware loading, too.
Tested on x86-64, sparc64 and mips64. Signed-off-by: René Rebe <r...@exactcode.de> diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig index 5b24f3959255..30d440bec257 100644 --- a/drivers/base/firmware_loader/Kconfig +++ b/drivers/base/firmware_loader/Kconfig @@ -169,6 +169,16 @@ config FW_LOADER_COMPRESS 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 FW_LOADER_PAGED_BUF + select ZSTD_DECOMPRESS + help + This option enables the support for loading Zstd 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. + 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 9da0c9d5f538..5deb73dbe81e 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -33,7 +33,9 @@ #include <linux/syscore_ops.h> #include <linux/reboot.h> #include <linux/security.h> +#include <linux/decompress/mm.h> #include <linux/xz.h> +#include <linux/zstd.h> #include <generated/utsrelease.h> @@ -435,6 +437,140 @@ static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv, } #endif /* CONFIG_FW_LOADER_COMPRESS */ +/* + * Zstd-compressed firmware support + */ +#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD +/* show an error and return the standard error code */ +static int handle_zstd_error(size_t ret) +{ + const int err = ZSTD_getErrorCode(ret); + + if (!ZSTD_isError(ret)) + return 0; + + switch (err) { + case ZSTD_error_memory_allocation: + printk("ZSTD decompressor ran out of memory"); + break; + case ZSTD_error_prefix_unknown: + printk("Input is not in the ZSTD format (wrong magic bytes)"); + break; + case ZSTD_error_dstSize_tooSmall: + case ZSTD_error_corruption_detected: + case ZSTD_error_checksum_wrong: + printk("ZSTD-compressed data is corrupt"); + break; + default: + printk("ZSTD-compressed data is probably corrupt"); + break; + } + return -1; +} + +/* single-shot decompression onto the pre-allocated buffer */ +static int fw_decompress_zstd_single(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + const size_t wksp_size = ZSTD_DCtxWorkspaceBound(); + void *wksp = large_malloc(wksp_size); + ZSTD_DCtx *dctx = ZSTD_initDCtx(wksp, wksp_size); + int err; + size_t ret; + + printk("zstd_single\n"); + + if (dctx == NULL) { + dev_warn(dev, "Out of memory while allocating ZSTD_DCtx"); + err = -1; + goto out; + } + /* Find out how large the frame actually is, there may be junk at + * the end of the frame that ZSTD_decompressDCtx() can't handle. + */ + ret = ZSTD_findFrameCompressedSize(in_buffer, in_size); + err = handle_zstd_error(ret); + if (err) + goto out; + in_size = (long)ret; + + ret = ZSTD_decompressDCtx(dctx, fw_priv->data, fw_priv->allocated_size, in_buffer, in_size); + err = handle_zstd_error(ret); + if (err) + goto out; + + fw_priv->size = ret; + +out: + if (wksp != NULL) + large_free(wksp); + return err; +} + +/* decompression on paged buffer and map it */ +static int fw_decompress_zstd_pages(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ +#if 0 + struct zstd_dec *zstd_dec; + struct zstd_buf zstd_buf; + enum zstd_ret zstd_ret; + struct page *page; + int err = 0; + + printk("zstd_pages\n"); + + zstd_dec = zstd_dec_init(ZSTD_DYNALLOC, (u32)-1); + if (!zstd_dec) + return -ENOMEM; + + zstd_buf.in_size = in_size; + zstd_buf.in = in_buffer; + zstd_buf.in_pos = 0; + + fw_priv->is_paged_buf = true; + fw_priv->size = 0; + do { + if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) { + err = -ENOMEM; + goto out; + } + + /* decompress onto the new allocated page */ + page = fw_priv->pages[fw_priv->nr_pages - 1]; + zstd_buf.out = kmap(page); + zstd_buf.out_pos = 0; + zstd_buf.out_size = PAGE_SIZE; + zstd_ret = zstd_dec_run(zstd_dec, &zstd_buf); + kunmap(page); + fw_priv->size += zstd_buf.out_pos; + /* partial decompression means either end or error */ + if (zstd_buf.out_pos != PAGE_SIZE) + break; + } while (zstd_ret == ZSTD_OK); + + err = fw_decompress_zstd_error(dev, zstd_ret); + if (!err) + err = fw_map_paged_buf(fw_priv); + + out: + zstd_dec_end(zstd_dec); + return err; +#endif + return -ENOMEM; +} + +static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + /* if the buffer is pre-allocated, we can perform in single-shot mode */ + if (fw_priv->data) + return fw_decompress_zstd_single(dev, fw_priv, in_size, in_buffer); + else + return fw_decompress_zstd_pages(dev, fw_priv, in_size, in_buffer); +} +#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */ + /* direct firmware loading support */ static char fw_path_para[256]; static const char * const fw_path[] = { @@ -773,6 +909,11 @@ _request_firmware(const struct firmware **firmware_p, const char *name, ret = fw_get_filesystem_firmware(device, fw->priv, ".xz", fw_decompress_xz); #endif +#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD + if (ret == -ENOENT) + ret = fw_get_filesystem_firmware(device, fw->priv, ".zst", + fw_decompress_zstd); +#endif if (ret == -ENOENT) ret = firmware_fallback_platform(fw->priv, opt_flags); -- René Rebe, ExactCODE GmbH, Lietzenburger Str. 42, DE-10789 Berlin https://exactcode.com | https://t2sde.org | https://rene.rebe.de