Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / lib / decompress_unlz4.c

diff --git a/kernel/lib/decompress_unlz4.c b/kernel/lib/decompress_unlz4.c
new file mode 100644 (file)
index 0000000..40f66eb
--- /dev/null
+++ b/kernel/lib/decompress_unlz4.c
@@ -0,0 +1,209 @@
+/*
+ * Wrapper for decompressing LZ4-compressed kernel, initramfs, and initrd
+ *
+ * Copyright (C) 2013, LG Electronics, Kyungsik Lee <kyungsik.lee@lge.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifdef STATIC
+#define PREBOOT
+#include "lz4/lz4_decompress.c"
+#else
+#include <linux/decompress/unlz4.h>
+#endif
+#include <linux/types.h>
+#include <linux/lz4.h>
+#include <linux/decompress/mm.h>
+#include <linux/compiler.h>
+
+#include <asm/unaligned.h>
+
+/*
+ * Note: Uncompressed chunk size is used in the compressor side
+ * (userspace side for compression).
+ * It is hardcoded because there is not proper way to extract it
+ * from the binary stream which is generated by the preliminary
+ * version of LZ4 tool so far.
+ */
+#define LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE (8 << 20)
+#define ARCHIVE_MAGICNUMBER 0x184C2102
+
+STATIC inline int INIT unlz4(u8 *input, long in_len,
+                               long (*fill)(void *, unsigned long),
+                               long (*flush)(void *, unsigned long),
+                               u8 *output, long *posp,
+                               void (*error) (char *x))
+{
+       int ret = -1;
+       size_t chunksize = 0;
+       size_t uncomp_chunksize = LZ4_DEFAULT_UNCOMPRESSED_CHUNK_SIZE;
+       u8 *inp;
+       u8 *inp_start;
+       u8 *outp;
+       long size = in_len;
+#ifdef PREBOOT
+       size_t out_len = get_unaligned_le32(input + in_len);
+#endif
+       size_t dest_len;
+
+
+       if (output) {
+               outp = output;
+       } else if (!flush) {
+               error("NULL output pointer and no flush function provided");
+               goto exit_0;
+       } else {
+               outp = large_malloc(uncomp_chunksize);
+               if (!outp) {
+                       error("Could not allocate output buffer");
+                       goto exit_0;
+               }
+       }
+
+       if (input && fill) {
+               error("Both input pointer and fill function provided,");
+               goto exit_1;
+       } else if (input) {
+               inp = input;
+       } else if (!fill) {
+               error("NULL input pointer and missing fill function");
+               goto exit_1;
+       } else {
+               inp = large_malloc(lz4_compressbound(uncomp_chunksize));
+               if (!inp) {
+                       error("Could not allocate input buffer");
+                       goto exit_1;
+               }
+       }
+       inp_start = inp;
+
+       if (posp)
+               *posp = 0;
+
+       if (fill) {
+               size = fill(inp, 4);
+               if (size < 4) {
+                       error("data corrupted");
+                       goto exit_2;
+               }
+       }
+
+       chunksize = get_unaligned_le32(inp);
+       if (chunksize == ARCHIVE_MAGICNUMBER) {
+               if (!fill) {
+                       inp += 4;
+                       size -= 4;
+               }
+       } else {
+               error("invalid header");
+               goto exit_2;
+       }
+
+       if (posp)
+               *posp += 4;
+
+       for (;;) {
+
+               if (fill) {
+                       size = fill(inp, 4);
+                       if (size == 0)
+                               break;
+                       if (size < 4) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
+               }
+
+               chunksize = get_unaligned_le32(inp);
+               if (chunksize == ARCHIVE_MAGICNUMBER) {
+                       if (!fill) {
+                               inp += 4;
+                               size -= 4;
+                       }
+                       if (posp)
+                               *posp += 4;
+                       continue;
+               }
+
+
+               if (posp)
+                       *posp += 4;
+
+               if (!fill) {
+                       inp += 4;
+                       size -= 4;
+               } else {
+                       if (chunksize > lz4_compressbound(uncomp_chunksize)) {
+                               error("chunk length is longer than allocated");
+                               goto exit_2;
+                       }
+                       size = fill(inp, chunksize);
+                       if (size < chunksize) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
+               }
+#ifdef PREBOOT
+               if (out_len >= uncomp_chunksize) {
+                       dest_len = uncomp_chunksize;
+                       out_len -= dest_len;
+               } else
+                       dest_len = out_len;
+               ret = lz4_decompress(inp, &chunksize, outp, dest_len);
+#else
+               dest_len = uncomp_chunksize;
+               ret = lz4_decompress_unknownoutputsize(inp, chunksize, outp,
+                               &dest_len);
+#endif
+               if (ret < 0) {
+                       error("Decoding failed");
+                       goto exit_2;
+               }
+
+               ret = -1;
+               if (flush && flush(outp, dest_len) != dest_len)
+                       goto exit_2;
+               if (output)
+                       outp += dest_len;
+               if (posp)
+                       *posp += chunksize;
+
+               if (!fill) {
+                       size -= chunksize;
+
+                       if (size == 0)
+                               break;
+                       else if (size < 0) {
+                               error("data corrupted");
+                               goto exit_2;
+                       }
+                       inp += chunksize;
+               }
+       }
+
+       ret = 0;
+exit_2:
+       if (!input)
+               large_free(inp_start);
+exit_1:
+       if (!output)
+               large_free(outp);
+exit_0:
+       return ret;
+}
+
+#ifdef PREBOOT
+STATIC int INIT decompress(unsigned char *buf, long in_len,
+                             long (*fill)(void*, unsigned long),
+                             long (*flush)(void*, unsigned long),
+                             unsigned char *output,
+                             long *posp,
+                             void(*error)(char *x)
+       )
+{
+       return unlz4(buf, in_len - 4, fill, flush, output, posp, error);
+}
+#endif