 98310e581e
			
		
	
	
	98310e581e
	
	
	
		
			
			Decompression errors can arise due to corruption of compressed blocks on flash or in memory. This patch propagates errors detected during decompression back to the block layer. Signed-off-by: David VomLehn <dvomlehn@cisco.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			77 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
	
		
			1.7 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * uncompress.c
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|  *
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|  * (C) Copyright 1999 Linus Torvalds
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|  *
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|  * cramfs interfaces to the uncompression library. There's really just
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|  * three entrypoints:
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|  *
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|  *  - cramfs_uncompress_init() - called to initialize the thing.
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|  *  - cramfs_uncompress_exit() - tell me when you're done
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|  *  - cramfs_uncompress_block() - uncompress a block.
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|  *
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|  * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
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|  * only have one stream, and we'll initialize it only once even if it
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|  * then is used by multiple filesystems.
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/errno.h>
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| #include <linux/vmalloc.h>
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| #include <linux/zlib.h>
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| #include <linux/cramfs_fs.h>
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| 
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| static z_stream stream;
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| static int initialized;
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| 
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| /* Returns length of decompressed data. */
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| int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen)
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| {
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| 	int err;
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| 
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| 	stream.next_in = src;
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| 	stream.avail_in = srclen;
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| 
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| 	stream.next_out = dst;
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| 	stream.avail_out = dstlen;
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| 
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| 	err = zlib_inflateReset(&stream);
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| 	if (err != Z_OK) {
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| 		printk("zlib_inflateReset error %d\n", err);
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| 		zlib_inflateEnd(&stream);
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| 		zlib_inflateInit(&stream);
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| 	}
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| 
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| 	err = zlib_inflate(&stream, Z_FINISH);
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| 	if (err != Z_STREAM_END)
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| 		goto err;
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| 	return stream.total_out;
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| 
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| err:
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| 	printk("Error %d while decompressing!\n", err);
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| 	printk("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen);
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| 	return -EIO;
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| }
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| 
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| int cramfs_uncompress_init(void)
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| {
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| 	if (!initialized++) {
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| 		stream.workspace = vmalloc(zlib_inflate_workspacesize());
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| 		if ( !stream.workspace ) {
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| 			initialized = 0;
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| 			return -ENOMEM;
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| 		}
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| 		stream.next_in = NULL;
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| 		stream.avail_in = 0;
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| 		zlib_inflateInit(&stream);
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| 	}
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| 	return 0;
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| }
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| 
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| void cramfs_uncompress_exit(void)
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| {
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| 	if (!--initialized) {
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| 		zlib_inflateEnd(&stream);
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| 		vfree(stream.workspace);
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| 	}
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| }
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