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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/zlib_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/zlib_wrapper.c')
-rw-r--r--fs/squashfs/zlib_wrapper.c137
1 files changed, 137 insertions, 0 deletions
diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c
new file mode 100644
index 000000000..cbb7afe7b
--- /dev/null
+++ b/fs/squashfs/zlib_wrapper.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+ * Phillip Lougher <phillip@squashfs.org.uk>
+ *
+ * zlib_wrapper.c
+ */
+
+
+#include <linux/mutex.h>
+#include <linux/bio.h>
+#include <linux/slab.h>
+#include <linux/zlib.h>
+#include <linux/vmalloc.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs.h"
+#include "decompressor.h"
+#include "page_actor.h"
+
+static void *zlib_init(struct squashfs_sb_info *dummy, void *buff)
+{
+ z_stream *stream = kmalloc(sizeof(z_stream), GFP_KERNEL);
+ if (stream == NULL)
+ goto failed;
+ stream->workspace = vmalloc(zlib_inflate_workspacesize());
+ if (stream->workspace == NULL)
+ goto failed;
+
+ return stream;
+
+failed:
+ ERROR("Failed to allocate zlib workspace\n");
+ kfree(stream);
+ return ERR_PTR(-ENOMEM);
+}
+
+
+static void zlib_free(void *strm)
+{
+ z_stream *stream = strm;
+
+ if (stream)
+ vfree(stream->workspace);
+ kfree(stream);
+}
+
+
+static int zlib_uncompress(struct squashfs_sb_info *msblk, void *strm,
+ struct bio *bio, int offset, int length,
+ struct squashfs_page_actor *output)
+{
+ struct bvec_iter_all iter_all = {};
+ struct bio_vec *bvec = bvec_init_iter_all(&iter_all);
+ int zlib_init = 0, error = 0;
+ z_stream *stream = strm;
+
+ stream->avail_out = PAGE_SIZE;
+ stream->next_out = squashfs_first_page(output);
+ stream->avail_in = 0;
+
+ if (IS_ERR(stream->next_out)) {
+ error = PTR_ERR(stream->next_out);
+ goto finish;
+ }
+
+ for (;;) {
+ int zlib_err;
+
+ if (stream->avail_in == 0) {
+ const void *data;
+ int avail;
+
+ if (!bio_next_segment(bio, &iter_all)) {
+ /* Z_STREAM_END must be reached. */
+ error = -EIO;
+ break;
+ }
+
+ avail = min(length, ((int)bvec->bv_len) - offset);
+ data = bvec_virt(bvec);
+ length -= avail;
+ stream->next_in = data + offset;
+ stream->avail_in = avail;
+ offset = 0;
+ }
+
+ if (stream->avail_out == 0) {
+ stream->next_out = squashfs_next_page(output);
+ if (IS_ERR(stream->next_out)) {
+ error = PTR_ERR(stream->next_out);
+ break;
+ } else if (stream->next_out != NULL)
+ stream->avail_out = PAGE_SIZE;
+ }
+
+ if (!zlib_init) {
+ zlib_err = zlib_inflateInit(stream);
+ if (zlib_err != Z_OK) {
+ error = -EIO;
+ break;
+ }
+ zlib_init = 1;
+ }
+
+ zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);
+ if (zlib_err == Z_STREAM_END)
+ break;
+ if (zlib_err != Z_OK) {
+ error = -EIO;
+ break;
+ }
+ }
+
+finish:
+ squashfs_finish_page(output);
+
+ if (!error)
+ if (zlib_inflateEnd(stream) != Z_OK)
+ error = -EIO;
+
+ return error ? error : stream->total_out;
+}
+
+const struct squashfs_decompressor squashfs_zlib_comp_ops = {
+ .init = zlib_init,
+ .free = zlib_free,
+ .decompress = zlib_uncompress,
+ .id = ZLIB_COMPRESSION,
+ .name = "zlib",
+ .alloc_buffer = 1,
+ .supported = 1
+};
+