linux/fs/squashfs/zstd_wrapper.c
Thomas Gleixner 3e0a4e8580 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 or at your option any
  later version 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091651.032047323@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:02 +02:00

143 lines
2.9 KiB
C

// 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/buffer_head.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_DStreamWorkspaceBound(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 buffer_head **bh, int b, int offset, int length,
struct squashfs_page_actor *output)
{
struct workspace *wksp = strm;
ZSTD_DStream *stream;
size_t total_out = 0;
size_t zstd_err;
int k = 0;
ZSTD_inBuffer in_buf = { NULL, 0, 0 };
ZSTD_outBuffer out_buf = { NULL, 0, 0 };
stream = ZSTD_initDStream(wksp->window_size, wksp->mem, wksp->mem_size);
if (!stream) {
ERROR("Failed to initialize zstd decompressor\n");
goto out;
}
out_buf.size = PAGE_SIZE;
out_buf.dst = squashfs_first_page(output);
do {
if (in_buf.pos == in_buf.size && k < b) {
int avail = min(length, msblk->devblksize - offset);
length -= avail;
in_buf.src = bh[k]->b_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 (out_buf.dst == NULL) {
/* Shouldn't run out of pages
* before stream is done.
*/
squashfs_finish_page(output);
goto out;
}
out_buf.pos = 0;
out_buf.size = PAGE_SIZE;
}
total_out -= out_buf.pos;
zstd_err = ZSTD_decompressStream(stream, &out_buf, &in_buf);
total_out += out_buf.pos; /* add the additional data produced */
if (in_buf.pos == in_buf.size && k < b)
put_bh(bh[k++]);
} while (zstd_err != 0 && !ZSTD_isError(zstd_err));
squashfs_finish_page(output);
if (ZSTD_isError(zstd_err)) {
ERROR("zstd decompression error: %d\n",
(int)ZSTD_getErrorCode(zstd_err));
goto out;
}
if (k < b)
goto out;
return (int)total_out;
out:
for (; k < b; k++)
put_bh(bh[k]);
return -EIO;
}
const struct squashfs_decompressor squashfs_zstd_comp_ops = {
.init = zstd_init,
.free = zstd_free,
.decompress = zstd_uncompress,
.id = ZSTD_COMPRESSION,
.name = "zstd",
.supported = 1
};