v4.19.13 snapshot.
diff --git a/crypto/zstd.c b/crypto/zstd.c
new file mode 100644
index 0000000..9a76b3e
--- /dev/null
+++ b/crypto/zstd.c
@@ -0,0 +1,265 @@
+/*
+ * Cryptographic API.
+ *
+ * Copyright (c) 2017-present, Facebook, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+#include <linux/crypto.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/vmalloc.h>
+#include <linux/zstd.h>
+#include <crypto/internal/scompress.h>
+
+
+#define ZSTD_DEF_LEVEL 3
+
+struct zstd_ctx {
+ ZSTD_CCtx *cctx;
+ ZSTD_DCtx *dctx;
+ void *cwksp;
+ void *dwksp;
+};
+
+static ZSTD_parameters zstd_params(void)
+{
+ return ZSTD_getParams(ZSTD_DEF_LEVEL, 0, 0);
+}
+
+static int zstd_comp_init(struct zstd_ctx *ctx)
+{
+ int ret = 0;
+ const ZSTD_parameters params = zstd_params();
+ const size_t wksp_size = ZSTD_CCtxWorkspaceBound(params.cParams);
+
+ ctx->cwksp = vzalloc(wksp_size);
+ if (!ctx->cwksp) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ctx->cctx = ZSTD_initCCtx(ctx->cwksp, wksp_size);
+ if (!ctx->cctx) {
+ ret = -EINVAL;
+ goto out_free;
+ }
+out:
+ return ret;
+out_free:
+ vfree(ctx->cwksp);
+ goto out;
+}
+
+static int zstd_decomp_init(struct zstd_ctx *ctx)
+{
+ int ret = 0;
+ const size_t wksp_size = ZSTD_DCtxWorkspaceBound();
+
+ ctx->dwksp = vzalloc(wksp_size);
+ if (!ctx->dwksp) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ ctx->dctx = ZSTD_initDCtx(ctx->dwksp, wksp_size);
+ if (!ctx->dctx) {
+ ret = -EINVAL;
+ goto out_free;
+ }
+out:
+ return ret;
+out_free:
+ vfree(ctx->dwksp);
+ goto out;
+}
+
+static void zstd_comp_exit(struct zstd_ctx *ctx)
+{
+ vfree(ctx->cwksp);
+ ctx->cwksp = NULL;
+ ctx->cctx = NULL;
+}
+
+static void zstd_decomp_exit(struct zstd_ctx *ctx)
+{
+ vfree(ctx->dwksp);
+ ctx->dwksp = NULL;
+ ctx->dctx = NULL;
+}
+
+static int __zstd_init(void *ctx)
+{
+ int ret;
+
+ ret = zstd_comp_init(ctx);
+ if (ret)
+ return ret;
+ ret = zstd_decomp_init(ctx);
+ if (ret)
+ zstd_comp_exit(ctx);
+ return ret;
+}
+
+static void *zstd_alloc_ctx(struct crypto_scomp *tfm)
+{
+ int ret;
+ struct zstd_ctx *ctx;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return ERR_PTR(-ENOMEM);
+
+ ret = __zstd_init(ctx);
+ if (ret) {
+ kfree(ctx);
+ return ERR_PTR(ret);
+ }
+
+ return ctx;
+}
+
+static int zstd_init(struct crypto_tfm *tfm)
+{
+ struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ return __zstd_init(ctx);
+}
+
+static void __zstd_exit(void *ctx)
+{
+ zstd_comp_exit(ctx);
+ zstd_decomp_exit(ctx);
+}
+
+static void zstd_free_ctx(struct crypto_scomp *tfm, void *ctx)
+{
+ __zstd_exit(ctx);
+ kzfree(ctx);
+}
+
+static void zstd_exit(struct crypto_tfm *tfm)
+{
+ struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ __zstd_exit(ctx);
+}
+
+static int __zstd_compress(const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen, void *ctx)
+{
+ size_t out_len;
+ struct zstd_ctx *zctx = ctx;
+ const ZSTD_parameters params = zstd_params();
+
+ out_len = ZSTD_compressCCtx(zctx->cctx, dst, *dlen, src, slen, params);
+ if (ZSTD_isError(out_len))
+ return -EINVAL;
+ *dlen = out_len;
+ return 0;
+}
+
+static int zstd_compress(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ return __zstd_compress(src, slen, dst, dlen, ctx);
+}
+
+static int zstd_scompress(struct crypto_scomp *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen,
+ void *ctx)
+{
+ return __zstd_compress(src, slen, dst, dlen, ctx);
+}
+
+static int __zstd_decompress(const u8 *src, unsigned int slen,
+ u8 *dst, unsigned int *dlen, void *ctx)
+{
+ size_t out_len;
+ struct zstd_ctx *zctx = ctx;
+
+ out_len = ZSTD_decompressDCtx(zctx->dctx, dst, *dlen, src, slen);
+ if (ZSTD_isError(out_len))
+ return -EINVAL;
+ *dlen = out_len;
+ return 0;
+}
+
+static int zstd_decompress(struct crypto_tfm *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+ struct zstd_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ return __zstd_decompress(src, slen, dst, dlen, ctx);
+}
+
+static int zstd_sdecompress(struct crypto_scomp *tfm, const u8 *src,
+ unsigned int slen, u8 *dst, unsigned int *dlen,
+ void *ctx)
+{
+ return __zstd_decompress(src, slen, dst, dlen, ctx);
+}
+
+static struct crypto_alg alg = {
+ .cra_name = "zstd",
+ .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
+ .cra_ctxsize = sizeof(struct zstd_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_init = zstd_init,
+ .cra_exit = zstd_exit,
+ .cra_u = { .compress = {
+ .coa_compress = zstd_compress,
+ .coa_decompress = zstd_decompress } }
+};
+
+static struct scomp_alg scomp = {
+ .alloc_ctx = zstd_alloc_ctx,
+ .free_ctx = zstd_free_ctx,
+ .compress = zstd_scompress,
+ .decompress = zstd_sdecompress,
+ .base = {
+ .cra_name = "zstd",
+ .cra_driver_name = "zstd-scomp",
+ .cra_module = THIS_MODULE,
+ }
+};
+
+static int __init zstd_mod_init(void)
+{
+ int ret;
+
+ ret = crypto_register_alg(&alg);
+ if (ret)
+ return ret;
+
+ ret = crypto_register_scomp(&scomp);
+ if (ret)
+ crypto_unregister_alg(&alg);
+
+ return ret;
+}
+
+static void __exit zstd_mod_fini(void)
+{
+ crypto_unregister_alg(&alg);
+ crypto_unregister_scomp(&scomp);
+}
+
+module_init(zstd_mod_init);
+module_exit(zstd_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Zstd Compression Algorithm");
+MODULE_ALIAS_CRYPTO("zstd");