loader: Add load_image_gzipped function.
As the name suggests this lets you load a ROM/disk image that is
gzipped. It is uncompressed before storing it in guest memory.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 1407831259-2115-2-git-send-email-rjones@redhat.com
[PMM: removed stray space before ')']
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 1a53f0f..193f0f8 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -577,6 +577,54 @@
return load_uboot_image(filename, NULL, &addr, NULL, IH_TYPE_RAMDISK);
}
+/* This simply prevents g_malloc in the function below from allocating
+ * a huge amount of memory, by placing a limit on the maximum
+ * uncompressed image size that load_image_gzipped will read.
+ */
+#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20)
+
+/* Load a gzip-compressed kernel. */
+int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
+{
+ uint8_t *compressed_data = NULL;
+ uint8_t *data = NULL;
+ gsize len;
+ ssize_t bytes;
+ int ret = -1;
+
+ if (!g_file_get_contents(filename, (char **) &compressed_data, &len,
+ NULL)) {
+ goto out;
+ }
+
+ /* Is it a gzip-compressed file? */
+ if (len < 2 ||
+ compressed_data[0] != 0x1f ||
+ compressed_data[1] != 0x8b) {
+ goto out;
+ }
+
+ if (max_sz > LOAD_IMAGE_MAX_GUNZIP_BYTES) {
+ max_sz = LOAD_IMAGE_MAX_GUNZIP_BYTES;
+ }
+
+ data = g_malloc(max_sz);
+ bytes = gunzip(data, max_sz, compressed_data, len);
+ if (bytes < 0) {
+ fprintf(stderr, "%s: unable to decompress gzipped kernel file\n",
+ filename);
+ goto out;
+ }
+
+ rom_add_blob_fixed(filename, data, bytes, addr);
+ ret = bytes;
+
+ out:
+ g_free(compressed_data);
+ g_free(data);
+ return ret;
+}
+
/*
* Functions for reboot-persistent memory regions.
* - used for vga bios and option roms.
