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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/squashfs/zstd_wrapper.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/squashfs/zstd_wrapper.c')
-rw-r--r--fs/squashfs/zstd_wrapper.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/fs/squashfs/zstd_wrapper.c b/fs/squashfs/zstd_wrapper.c
new file mode 100644
index 000000000..0e407c4d8
--- /dev/null
+++ b/fs/squashfs/zstd_wrapper.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2016-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * zstd_wrapper.c
+ */
+
+#include <linux/mutex.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+#include <linux/zstd.h>
+#include <linux/vmalloc.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+#include "decompressor.h"
+#include "page_actor.h"
+
+struct workspace {
+ void *mem;
+ size_t mem_size;
+ size_t window_size;
+};
+
+static void *zstd_init(struct squashfs_sb_info *msblk, void *buff)
+{
+ struct workspace *wksp = kmalloc(sizeof(*wksp), GFP_KERNEL);
+
+ if (wksp == NULL)
+ goto failed;
+ wksp->window_size = max_t(size_t,
+ msblk->block_size, SQUASHFS_METADATA_SIZE);
+ wksp->mem_size = zstd_dstream_workspace_bound(wksp->window_size);
+ wksp->mem = vmalloc(wksp->mem_size);
+ if (wksp->mem == NULL)
+ goto failed;
+
+ return wksp;
+
+failed:
+ ERROR("Failed to allocate zstd workspace\n");
+ kfree(wksp);
+ return ERR_PTR(-ENOMEM);
+}
+
+
+static void zstd_free(void *strm)
+{
+ struct workspace *wksp = strm;
+
+ if (wksp)
+ vfree(wksp->mem);
+ kfree(wksp);
+}
+
+
+static int zstd_uncompress(struct squashfs_sb_info *msblk, void *strm,
+ struct bio *bio, int offset, int length,
+ struct squashfs_page_actor *output)
+{
+ struct workspace *wksp = strm;
+ zstd_dstream *stream;
+ size_t total_out = 0;
+ int error = 0;
+ zstd_in_buffer in_buf = { NULL, 0, 0 };
+ zstd_out_buffer out_buf = { NULL, 0, 0 };
+ struct bvec_iter_all iter_all = {};
+ struct bio_vec *bvec = bvec_init_iter_all(&iter_all);
+
+ stream = zstd_init_dstream(wksp->window_size, wksp->mem, wksp->mem_size);
+
+ if (!stream) {
+ ERROR("Failed to initialize zstd decompressor\n");
+ return -EIO;
+ }
+
+ out_buf.size = PAGE_SIZE;
+ out_buf.dst = squashfs_first_page(output);
+ if (IS_ERR(out_buf.dst)) {
+ error = PTR_ERR(out_buf.dst);
+ goto finish;
+ }
+
+ for (;;) {
+ size_t zstd_err;
+
+ if (in_buf.pos == in_buf.size) {
+ const void *data;
+ int avail;
+
+ if (!bio_next_segment(bio, &iter_all)) {
+ error = -EIO;
+ break;
+ }
+
+ avail = min(length, ((int)bvec->bv_len) - offset);
+ data = bvec_virt(bvec);
+ length -= avail;
+ in_buf.src = data + offset;
+ in_buf.size = avail;
+ in_buf.pos = 0;
+ offset = 0;
+ }
+
+ if (out_buf.pos == out_buf.size) {
+ out_buf.dst = squashfs_next_page(output);
+ if (IS_ERR(out_buf.dst)) {
+ error = PTR_ERR(out_buf.dst);
+ break;
+ } else if (out_buf.dst == NULL) {
+ /* Shouldn't run out of pages
+ * before stream is done.
+ */
+ error = -EIO;
+ break;
+ }
+ out_buf.pos = 0;
+ out_buf.size = PAGE_SIZE;
+ }
+
+ total_out -= out_buf.pos;
+ zstd_err = zstd_decompress_stream(stream, &out_buf, &in_buf);
+ total_out += out_buf.pos; /* add the additional data produced */
+ if (zstd_err == 0)
+ break;
+
+ if (zstd_is_error(zstd_err)) {
+ ERROR("zstd decompression error: %d\n",
+ (int)zstd_get_error_code(zstd_err));
+ error = -EIO;
+ break;
+ }
+ }
+
+finish:
+
+ squashfs_finish_page(output);
+
+ return error ? error : total_out;
+}
+
+const struct squashfs_decompressor squashfs_zstd_comp_ops = {
+ .init = zstd_init,
+ .free = zstd_free,
+ .decompress = zstd_uncompress,
+ .id = ZSTD_COMPRESSION,
+ .name = "zstd",
+ .alloc_buffer = 1,
+ .supported = 1
+};