parisc: add support for kexec_file_load() syscall

Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 548c767f4358b18bb962bde18964ae5b93547cc1..2e757c785239a97a77bb4f1a04b63d374e4226e0 100644 (file)
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -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
 
 

diff --git a/arch/parisc/kernel/Makefile b/arch/parisc/kernel/Makefile
index 487cf88866a8ad029a4fd11c7fa99e0f92775636..2663c8f8be115a0929b2e6f933f4b3e05ca9e98d 100644 (file)
--- a/arch/parisc/kernel/Makefile
+++ b/arch/parisc/kernel/Makefile
@@ -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

diff --git a/arch/parisc/kernel/kexec.c b/arch/parisc/kernel/kexec.c
index a92d265a2261301b3ac02dd87f74ccc1a3711560..5eb7f30edc1f7da3eedd284ada33cda9ef0a9d52 100644 (file)
--- a/arch/parisc/kernel/kexec.c
+++ b/arch/parisc/kernel/kexec.c
@@ -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)

diff --git a/arch/parisc/kernel/kexec_file.c b/arch/parisc/kernel/kexec_file.c
new file mode 100644 (file)
index 0000000..8c53420
--- /dev/null
+++ b/arch/parisc/kernel/kexec_file.c
@@ -0,0 +1,86 @@
+// 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
+};