1 files changed, 73 insertions, 3 deletions

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>
@@ -305,9 +306,73 @@ 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);