[PATCH 03/49] zstd: Create a function for use from U-Boot

Simon Glass
2021-05-03T23:10:50Z

The existing zstd API requires the same sequence of calls to perform its
task. Create a helper for U-Boot, to avoid code duplication, as is done
with other compression algorithms. Make use of of this from the image
code.

Note that the zstd code lacks a test in test/compression.c and this should
be added by the maintainer.

Signed-off-by: Simon Glass <sjg@chromium.org>
---

(no changes since v1)

common/image.c | 50 +++++++---------------------------
include/linux/zstd.h | 11 ++++++++
lib/zstd/Makefile | 2 +-
lib/zstd/zstd.c | 64 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 85 insertions(+), 42 deletions(-)
create mode 100644 lib/zstd/zstd.c

diff --git a/common/image.c b/common/image.c
index 51854aae5dd..062e08886fd 100644
--- a/common/image.c
+++ b/common/image.c
@@ -22,6 +22,7 @@
#include <status_led.h>
#endif

+#include <abuf.h>
#include <rtc.h>

#include <gzip.h>
@@ -525,50 +526,17 @@ int image_decomp(int comp, ulong load, ulong image_start, int type,
#ifndef USE_HOSTCC
#if CONFIG_IS_ENABLED(ZSTD)
case IH_COMP_ZSTD: {
- size_t size = unc_len;
- ZSTD_DStream *dstream;
- ZSTD_inBuffer in_buf;
- ZSTD_outBuffer out_buf;
- void *workspace;
- size_t wsize;
-
- wsize = ZSTD_DStreamWorkspaceBound(image_len);
- workspace = malloc(wsize);
- if (!workspace) {
- debug("%s: cannot allocate workspace of size %zu\n", __func__,
- wsize);
- return -1;
- }
-
- dstream = ZSTD_initDStream(image_len, workspace, wsize);
- if (!dstream) {
- printf("%s: ZSTD_initDStream failed\n", __func__);
- return ZSTD_getErrorCode(ret);
- }
-
- in_buf.src = image_buf;
- in_buf.pos = 0;
- in_buf.size = image_len;
+ struct abuf in, out;

- out_buf.dst = load_buf;
- out_buf.pos = 0;
- out_buf.size = size;
-
- while (1) {
- size_t ret;
-
- ret = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
- if (ZSTD_isError(ret)) {
- printf("%s: ZSTD_decompressStream error %d\n", __func__,
- ZSTD_getErrorCode(ret));
- return ZSTD_getErrorCode(ret);
- }
-
- if (in_buf.pos >= image_len || !ret)
- break;
+ abuf_init_set(&in, image_buf, image_len);
+ abuf_init_set(&in, load_buf, unc_len);
+ ret = zstd_decompress(&in, &out);
+ if (ret < 0) {
+ printf("ZSTD decompression failed\n");
+ return ret;
}

- image_len = out_buf.pos;
+ image_len = ret;

break;
}
diff --git a/include/linux/zstd.h b/include/linux/zstd.h
index 724f69350e0..35ba4c90aa4 100644
--- a/include/linux/zstd.h
+++ b/include/linux/zstd.h
@@ -1144,4 +1144,15 @@ size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity,
size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart,
size_t blockSize);

+struct abuf;
+
+/**
+ * zstd_decompress() - Decompress Zstandard data
+ *
+ * @in: Input buffer to decompress
+ * @out: Output buffer to hold the results (must be large enough)
+ * @return size of the decompressed data, or -ve on error
+ */
+int zstd_decompress(struct abuf *in, struct abuf *out);
+
#endif /* ZSTD_H */
diff --git a/lib/zstd/Makefile b/lib/zstd/Makefile
index 33c1df48ec8..12170892923 100644
--- a/lib/zstd/Makefile
+++ b/lib/zstd/Makefile
@@ -1,4 +1,4 @@
obj-y += zstd_decompress.o

zstd_decompress-y := huf_decompress.o decompress.o \
- entropy_common.o fse_decompress.o zstd_common.o
+ entropy_common.o fse_decompress.o zstd_common.o zstd.o
diff --git a/lib/zstd/zstd.c b/lib/zstd/zstd.c
new file mode 100644
index 00000000000..bf9cd19cfa3
--- /dev/null
+++ b/lib/zstd/zstd.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2021 Google LLC
+ */
+
+#define LOG_CATEGORY LOGC_BOOT
+
+#include <common.h>
+#include <abuf.h>
+#include <log.h>
+#include <malloc.h>
+#include <linux/zstd.h>
+
+int zstd_decompress(struct abuf *in, struct abuf *out)
+{
+ ZSTD_DStream *dstream;
+ ZSTD_inBuffer in_buf;
+ ZSTD_outBuffer out_buf;
+ void *workspace;
+ size_t wsize;
+ int ret;
+
+ wsize = ZSTD_DStreamWorkspaceBound(abuf_size(in));
+ workspace = malloc(wsize);
+ if (!workspace) {
+ debug("%s: cannot allocate workspace of size %zu\n", __func__,
+ wsize);
+ return -ENOMEM;
+ }
+
+ dstream = ZSTD_initDStream(abuf_size(in), workspace, wsize);
+ if (!dstream) {
+ log_err("%s: ZSTD_initDStream failed\n", __func__);
+ ret = -EPERM;
+ goto do_free;
+ }
+
+ in_buf.src = abuf_data(in);
+ in_buf.pos = 0;
+ in_buf.size = abuf_size(in);
+
+ out_buf.dst = abuf_data(out);
+ out_buf.pos = 0;
+ out_buf.size = abuf_size(out);
+
+ while (1) {
+ size_t res;
+
+ res = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
+ if (ZSTD_isError(res)) {
+ ret = ZSTD_getErrorCode(res);
+ log_err("ZSTD_decompressStream error %d\n", ret);
+ goto do_free;
+ }
+
+ if (in_buf.pos >= abuf_size(in) || !res)
+ break;
+ }
+
+ ret = out_buf.pos;
+do_free:
+ free(workspace);
+ return ret;
+}
--
2.31.1.527.g47e6f16901-goog