load_other_segments() sets up and adds all the memory segments necessary
other than kernel, including initrd, device-tree blob and purgatory.
Most of the code was borrowed from kexec-tools' counterpart.
In addition, arch_kexec_image_probe(), arch_kexec_image_load() and
arch_kexec_kernel_verify_sig() are stubs for supporting multiple types
of kernel image formats.
Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will.deacon at arm.com>
---
arch/arm64/include/asm/kexec.h | 18 +++
arch/arm64/kernel/machine_kexec_file.c | 255 +++++++++++++++++++++++++++++++++
2 files changed, 273 insertions(+)
diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h
index e17f0529a882..ebc4aaa707ae 100644
--- a/arch/arm64/include/asm/kexec.h
+++ b/arch/arm64/include/asm/kexec.h
@@ -93,6 +93,24 @@ static inline void crash_prepare_suspend(void) {}
static inline void crash_post_resume(void) {}
#endif
+#ifdef CONFIG_KEXEC_FILE
+#define ARCH_HAS_KIMAGE_ARCH
+
+struct kimage_arch {
+ void *dtb_buf;
+};
+
+struct kimage;
+extern int setup_dtb(struct kimage *image,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len,
+ char **dtb_buf, size_t *dtb_buf_len);
+extern int load_other_segments(struct kimage *image,
+ unsigned long kernel_load_addr,
+ char *initrd, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len);
+#endif
+
#endif /* __ASSEMBLY__ */
#endif
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 183f7776d6dd..cd12e451e474 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -16,8 +16,78 @@
#include <linux/elf.h>
#include <linux/errno.h>
#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
#include <linux/types.h>
#include <asm/byteorder.h>
+#include <asm/kexec_file.h>
+
+static int __dt_root_addr_cells;
+static int __dt_root_size_cells;
+
+static struct kexec_file_ops *kexec_file_loaders[0];
+
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ struct kexec_file_ops *fops;
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) {
+ fops = kexec_file_loaders[i];
+ if (!fops || !fops->probe)
+ continue;
+
+ ret = fops->probe(buf, buf_len);
+ if (!ret) {
+ image->fops = fops;
+ return 0;
+ }
+ }
+
+ return -ENOEXEC;
+}
+
+void *arch_kexec_kernel_image_load(struct kimage *image)
+{
+ if (!image->fops || !image->fops->load)
+ return ERR_PTR(-ENOEXEC);
+
+ return image->fops->load(image, image->kernel_buf,
+ image->kernel_buf_len, image->initrd_buf,
+ image->initrd_buf_len, image->cmdline_buf,
+ image->cmdline_buf_len);
+}
+
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+ vfree(image->arch.dtb_buf);
+ image->arch.dtb_buf = NULL;
+
+ vfree(image->arch.elf_headers);
+ image->arch.elf_headers = NULL;
+ image->arch.elf_headers_sz = 0;
+
+ if (!image->fops || !image->fops->cleanup)
+ return 0;
+
+ return image->fops->cleanup(image->image_loader_data);
+}
+
+#ifdef CONFIG_KEXEC_VERIFY_SIG
+int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel,
+ unsigned long kernel_len)
+{
+ if (!image->fops || !image->fops->verify_sig) {
+ pr_debug("kernel loader does not support signature verification.\n");
+ return -EKEYREJECTED;
+ }
+
+ return image->fops->verify_sig(kernel, kernel_len);
+}
+#endif
/*
* Apply purgatory relocations.
@@ -197,3 +267,188 @@ int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr,
return 0;
}
+
+int arch_kexec_walk_mem(struct kexec_buf *kbuf, int (*func)(u64, u64, void *))
+{
+ if (kbuf->image->type == KEXEC_TYPE_CRASH)
+ return walk_iomem_res_desc(crashk_res.desc,
+ IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY,
+ crashk_res.start, crashk_res.end,
+ kbuf, func);
+ else if (kbuf->top_down)
+ return walk_system_ram_res_rev(0, ULONG_MAX, kbuf, func);
+ else
+ return walk_system_ram_res(0, ULONG_MAX, kbuf, func);
+}
+
+int setup_dtb(struct kimage *image,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len,
+ char **dtb_buf, size_t *dtb_buf_len)
+{
+ char *buf = NULL;
+ size_t buf_size;
+ int nodeoffset;
+ u64 value;
+ int range_len;
+ int ret;
+
+ /* duplicate dt blob */
+ buf_size = fdt_totalsize(initial_boot_params);
+ range_len = (__dt_root_addr_cells + __dt_root_size_cells) * sizeof(u32);
+
+ if (initrd_load_addr)
+ buf_size += fdt_prop_len("initrd-start", sizeof(u64))
+ + fdt_prop_len("initrd-end", sizeof(u64));
+
+ if (cmdline)
+ buf_size += fdt_prop_len("bootargs", cmdline_len + 1);
+
+ buf = vmalloc(buf_size);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto out_err;
+ }
+
+ ret = fdt_open_into(initial_boot_params, buf, buf_size);
+ if (ret)
+ goto out_err;
+
+ nodeoffset = fdt_path_offset(buf, "/chosen");
+ if (nodeoffset < 0)
+ goto out_err;
+
+ /* add bootargs */
+ if (cmdline) {
+ ret = fdt_setprop(buf, nodeoffset, "bootargs",
+ cmdline, cmdline_len + 1);
+ if (ret)
+ goto out_err;
+ }
+
+ /* add initrd-* */
+ if (initrd_load_addr) {
+ value = cpu_to_fdt64(initrd_load_addr);
+ ret = fdt_setprop(buf, nodeoffset, "initrd-start",
+ &value, sizeof(value));
+ if (ret)
+ goto out_err;
+
+ value = cpu_to_fdt64(initrd_load_addr + initrd_len);
+ ret = fdt_setprop(buf, nodeoffset, "initrd-end",
+ &value, sizeof(value));
+ if (ret)
+ goto out_err;
+ }
+
+ /* trim a buffer */
+ fdt_pack(buf);
+ *dtb_buf = buf;
+ *dtb_buf_len = fdt_totalsize(buf);
+
+ return 0;
+
+out_err:
+ vfree(buf);
+ return ret;
+}
+
+int load_other_segments(struct kimage *image, unsigned long kernel_load_addr,
+ char *initrd, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len)
+{
+ struct kexec_buf kbuf;
+ unsigned long initrd_load_addr = 0;
+ unsigned long purgatory_load_addr, dtb_load_addr;
+ char *dtb = NULL;
+ unsigned long dtb_len;
+ int ret = 0;
+
+ kbuf.image = image;
+
+ /* Load initrd */
+ if (initrd) {
+ kbuf.buffer = initrd;
+ kbuf.bufsz = initrd_len;
+ kbuf.memsz = initrd_len;
+ kbuf.buf_align = PAGE_SIZE;
+ /* within 1GB-aligned window of up to 32GB in size */
+ kbuf.buf_min = kernel_load_addr;
+ kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
+ + (unsigned long)SZ_1G * 31;
+ kbuf.top_down = 0;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+ initrd_load_addr = kbuf.mem;
+
+ pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ initrd_load_addr, initrd_len, initrd_len);
+ }
+
+ /* Load dtb blob */
+ ret = setup_dtb(image, initrd_load_addr, initrd_len,
+ cmdline, cmdline_len, &dtb, &dtb_len);
+ if (ret) {
+ pr_err("Preparing for new dtb failed\n");
+ goto out_err;
+ }
+
+ kbuf.buffer = dtb;
+ kbuf.bufsz = dtb_len;
+ kbuf.memsz = dtb_len;
+ /* not across 2MB boundary */
+ kbuf.buf_align = SZ_2M;
+ /*
+ * Note for backporting:
+ * On kernel prior to v4.2, fdt must reside within 512MB block
+ * where the kernel also resides. So
+ * kbuf.buf_min = round_down(kernel_load_addr, SZ_512M);
+ * kbuf.buf_max = round_up(kernel_load_addr, SZ_512M);
+ * would be required.
+ */
+ kbuf.buf_min = kernel_load_addr;
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.top_down = 1;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+ dtb_load_addr = kbuf.mem;
+ image->arch.dtb_buf = dtb;
+
+ pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ dtb_load_addr, dtb_len, dtb_len);
+
+ /* Load purgatory */
+ ret = kexec_load_purgatory(image, kernel_load_addr, ULONG_MAX, 1,
+ &purgatory_load_addr);
+ if (ret) {
+ pr_err("Loading purgatory failed\n");
+ goto out_err;
+ }
+
+ ret = kexec_purgatory_get_set_symbol(image, "arm64_kernel_entry",
+ &kernel_load_addr, sizeof(kernel_load_addr), 0);
+ if (ret) {
+ pr_err("Relocating symbol (arm64_kernel_entry) failed.\n");
+ goto out_err;
+ }
+
+ ret = kexec_purgatory_get_set_symbol(image, "arm64_dtb_addr",
+ &dtb_load_addr, sizeof(dtb_load_addr), 0);
+ if (ret) {
+ pr_err("Relocating symbol (arm64_dtb_addr) failed.\n");
+ goto out_err;
+ }
+
+ pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr);
+
+ return 0;
+
+out_err:
+ vfree(dtb);
+ image->arch.dtb_buf = NULL;
+ return ret;
+}
--
2.14.1
