Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * uncompress.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * (C) Copyright 1999 Linus Torvalds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  * cramfs interfaces to the uncompression library. There's really just
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8)  * three entrypoints:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)  *  - cramfs_uncompress_init() - called to initialize the thing.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)  *  - cramfs_uncompress_exit() - tell me when you're done
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12)  *  - cramfs_uncompress_block() - uncompress a block.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)  * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)  * only have one stream, and we'll initialize it only once even if it
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)  * then is used by multiple filesystems.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #include <linux/vmalloc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #include <linux/zlib.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #include "internal.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) static z_stream stream;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) static int initialized;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) /* Returns length of decompressed data. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	stream.next_in = src;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	stream.avail_in = srclen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	stream.next_out = dst;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	stream.avail_out = dstlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	err = zlib_inflateReset(&stream);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	if (err != Z_OK) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 		pr_err("zlib_inflateReset error %d\n", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 		zlib_inflateEnd(&stream);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 		zlib_inflateInit(&stream);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	err = zlib_inflate(&stream, Z_FINISH);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	if (err != Z_STREAM_END)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		goto err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	return stream.total_out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) err:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) 	pr_err("Error %d while decompressing!\n", err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	pr_err("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) int cramfs_uncompress_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	if (!initialized++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		stream.workspace = vmalloc(zlib_inflate_workspacesize());
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		if (!stream.workspace) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 			initialized = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 			return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		stream.next_in = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 		stream.avail_in = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 		zlib_inflateInit(&stream);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) void cramfs_uncompress_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	if (!--initialized) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 		zlib_inflateEnd(&stream);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 		vfree(stream.workspace);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) }