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-rw-r--r--kexec/arch/arm64/kexec-vmlinuz-arm64.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/kexec/arch/arm64/kexec-vmlinuz-arm64.c b/kexec/arch/arm64/kexec-vmlinuz-arm64.c
new file mode 100644
index 0000000..c0ee47c
--- /dev/null
+++ b/kexec/arch/arm64/kexec-vmlinuz-arm64.c
@@ -0,0 +1,110 @@
+/*
+ * ARM64 PE compressed Image (vmlinuz, ZBOOT) support.
+ *
+ * Several distros use 'make zinstall' rule inside
+ * 'arch/arm64/boot/Makefile' to install the arm64
+ * ZBOOT compressed file inside the boot destination
+ * directory (for e.g. /boot).
+ *
+ * Currently we cannot use kexec_file_load() to load vmlinuz
+ * PE images that self decompress.
+ *
+ * To support ZBOOT, we should:
+ * a). Copy the compressed contents of vmlinuz to a temporary file.
+ * b). Decompress (gunzip-decompress) the contents inside the
+ * temporary file.
+ * c). Validate the resulting image and write it back to the
+ * temporary file.
+ * d). Pass the 'fd' of the temporary file to the kernel space.
+ *
+ * Note this, module doesn't provide a _load() function instead
+ * relying on image_arm64_load() to load the resulting decompressed
+ * image.
+ *
+ * So basically the kernel space still gets a decompressed
+ * kernel image to load via kexec-tools.
+ */
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include "kexec-arm64.h"
+#include <kexec-pe-zboot.h>
+#include "arch/options.h"
+
+static int kernel_fd = -1;
+
+/* Returns:
+ * -1 : in case of error/invalid format (not a valid PE+compressed ZBOOT format.
+ */
+int pez_arm64_probe(const char *kernel_buf, off_t kernel_size)
+{
+ int ret = -1;
+ const struct arm64_image_header *h;
+ char *buf;
+ off_t buf_sz;
+
+ buf = (char *)kernel_buf;
+ buf_sz = kernel_size;
+ if (!buf)
+ return -1;
+ h = (const struct arm64_image_header *)buf;
+
+ dbgprintf("%s: PROBE.\n", __func__);
+ if (buf_sz < sizeof(struct arm64_image_header)) {
+ dbgprintf("%s: Not large enough to be a PE image.\n", __func__);
+ return -1;
+ }
+ if (!arm64_header_check_pe_sig(h)) {
+ dbgprintf("%s: Not an PE image.\n", __func__);
+ return -1;
+ }
+
+ if (buf_sz < sizeof(struct arm64_image_header) + h->pe_header) {
+ dbgprintf("%s: PE image offset larger than image.\n", __func__);
+ return -1;
+ }
+
+ if (memcmp(&buf[h->pe_header],
+ arm64_pe_machtype, sizeof(arm64_pe_machtype))) {
+ dbgprintf("%s: PE header doesn't match machine type.\n", __func__);
+ return -1;
+ }
+
+ ret = pez_prepare(buf, buf_sz, &kernel_fd);
+
+ if (!ret) {
+ /* validate the arm64 specific header */
+ struct arm64_image_header hdr_check;
+ if (read(kernel_fd, &hdr_check, sizeof(hdr_check)) != sizeof(hdr_check))
+ goto bad_header;
+
+ lseek(kernel_fd, 0, SEEK_SET);
+
+ if (!arm64_header_check_magic(&hdr_check)) {
+ dbgprintf("%s: Bad arm64 image header.\n", __func__);
+ goto bad_header;
+ }
+ }
+
+ return ret;
+bad_header:
+ close(kernel_fd);
+ free(buf);
+ return -1;
+}
+
+int pez_arm64_load(int argc, char **argv, const char *buf, off_t len,
+ struct kexec_info *info)
+{
+ info->kernel_fd = kernel_fd;
+ return image_arm64_load(argc, argv, buf, len, info);
+}
+
+void pez_arm64_usage(void)
+{
+ printf(
+" An ARM64 vmlinuz, PE image of a compressed, little endian.\n"
+" kernel, built with ZBOOT enabled.\n\n");
+}