parisc: add support for kexec_file_load() syscall (1191cf49) · Commits · e / devices / android_kernel_fairphone_FP5

arch/parisc/Kconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -359,6 +359,16 @@ config KEXEC
		shutdown, so do not be surprised if this code does not
		initially work for you.

		config KEXEC_FILE
		bool "kexec file based system call"
		select KEXEC_CORE
		select KEXEC_ELF
		help
		This enables the kexec_file_load() System call. This is
		file based and takes file descriptors as system call argument
		for kernel and initramfs as opposed to list of segments as
		accepted by previous system call.

		endmenu

arch/parisc/kernel/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -38,3 +38,4 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
		obj-$(CONFIG_KGDB) += kgdb.o
		obj-$(CONFIG_KPROBES) += kprobes.o
		obj-$(CONFIG_KEXEC) += kexec.o relocate_kernel.o
		obj-$(CONFIG_KEXEC_FILE) += kexec_file.o

arch/parisc/kernel/kexec.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -40,6 +40,13 @@ static void kexec_image_info(const struct kimage *kimage)

		for (i = 0; i < kimage->nr_segments; i++)
		kexec_show_segment_info(kimage, i);

		#ifdef CONFIG_KEXEC_FILE
		if (kimage->file_mode) {
		pr_debug("cmdline: %.*s\n", (int)kimage->cmdline_buf_len,
		kimage->cmdline_buf);
		}
		#endif
		}

		void machine_kexec_cleanup(struct kimage *kimage)

arch/parisc/kernel/kexec_file.c

0 → 100644

+86 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/*
		* Load ELF vmlinux file for the kexec_file_load syscall.
		*
		* Copyright (c) 2019 Sven Schnelle <svens@stackframe.org>
		*
		*/
		#include <linux/elf.h>
		#include <linux/kexec.h>
		#include <linux/libfdt.h>
		#include <linux/module.h>
		#include <linux/of_fdt.h>
		#include <linux/slab.h>
		#include <linux/types.h>

		static void elf_load(struct kimage image, char *kernel_buf,
		unsigned long kernel_len, char *initrd,
		unsigned long initrd_len, char *cmdline,
		unsigned long cmdline_len)
		{
		int ret, i;
		unsigned long kernel_load_addr;
		struct elfhdr ehdr;
		struct kexec_elf_info elf_info;
		struct kexec_buf kbuf = { .image = image, .buf_min = 0,
		.buf_max = -1UL, };

		ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info);
		if (ret)
		goto out;

		ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr);
		if (ret)
		goto out;

		image->start = __pa(elf_info.ehdr->e_entry);

		for (i = 0; i < image->nr_segments; i++)
		image->segment[i].mem = __pa(image->segment[i].mem);

		pr_debug("Loaded the kernel at 0x%lx, entry at 0x%lx\n",
		kernel_load_addr, image->start);

		if (initrd != NULL) {
		kbuf.buffer = initrd;
		kbuf.bufsz = kbuf.memsz = initrd_len;
		kbuf.buf_align = PAGE_SIZE;
		kbuf.top_down = false;
		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
		ret = kexec_add_buffer(&kbuf);
		if (ret)
		goto out;

		pr_debug("Loaded initrd at 0x%lx\n", kbuf.mem);
		image->arch.initrd_start = kbuf.mem;
		image->arch.initrd_end = kbuf.mem + initrd_len;
		}

		if (cmdline != NULL) {
		kbuf.buffer = cmdline;
		kbuf.bufsz = kbuf.memsz = ALIGN(cmdline_len, 8);
		kbuf.buf_align = PAGE_SIZE;
		kbuf.top_down = false;
		kbuf.buf_min = PAGE0->mem_free + PAGE_SIZE;
		kbuf.buf_max = kernel_load_addr;
		kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
		ret = kexec_add_buffer(&kbuf);
		if (ret)
		goto out;

		pr_debug("Loaded cmdline at 0x%lx\n", kbuf.mem);
		image->arch.cmdline = kbuf.mem;
		}
		out:
		return NULL;
		}

		const struct kexec_file_ops kexec_elf_ops = {
		.probe = kexec_elf_probe,
		.load = elf_load,
		};

		const struct kexec_file_ops * const kexec_file_loaders[] = {
		&kexec_elf_ops,
		NULL
		};