powerpc/kexec_file: Mark PPC64 specific code

Some of the kexec_file_load code isn't PPC64 specific. Move PPC64
specific code from kexec/file_load.c to kexec/file_load_64.c. Also,
rename purgatory/trampoline.S to purgatory/trampoline_64.S in the same
spirit. No functional changes.

Signed-off-by: Hari Bathini <[e-mail]>
Tested-by: Pingfan Liu <[e-mail]>
Reviewed-by: Laurent Dufour <[e-mail]>
Reviewed-by: Thiago Jung Bauermann <[e-mail]>
Signed-off-by: Michael Ellerman <[e-mail]>
Link: https://lore.kernel.org/r/159602276920.575379.10390965946438306388.stgit@hbathini

arch/powerpc/include/asm/kexec.h

···
 		  unsigned long initrd_load_addr, unsigned long initrd_len,
 		  const char *cmdline);
 int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
+
+#ifdef CONFIG_PPC64
+int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
+			  const void *fdt, unsigned long kernel_load_addr,
+			  unsigned long fdt_load_addr);
+int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
+			unsigned long initrd_load_addr,
+			unsigned long initrd_len, const char *cmdline);
+#endif /* CONFIG_PPC64 */
 #endif /* CONFIG_KEXEC_FILE */
 
 #else /* !CONFIG_KEXEC_CORE */

arch/powerpc/kexec/Makefile

···
 
 obj-$(CONFIG_PPC32)		+= relocate_32.o
 
-obj-$(CONFIG_KEXEC_FILE)	+= file_load.o elf_$(BITS).o
+obj-$(CONFIG_KEXEC_FILE)	+= file_load.o file_load_$(BITS).o elf_$(BITS).o
 
 ifdef CONFIG_HAVE_IMA_KEXEC
 ifdef CONFIG_IMA

arch/powerpc/kexec/elf_64.c

···
 		goto out;
 	}
 
-	ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+	ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr,
+				  initrd_len, cmdline);
 	if (ret)
 		goto out;
 
···
 	pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
 
 	slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
-	ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
-			      fdt_load_addr);
+	ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr,
+				    fdt_load_addr);
 	if (ret)
 		pr_err("Error setting up the purgatory.\n");
 

arch/powerpc/kexec/file_load.c

···
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * ppc64 code to implement the kexec_file_load syscall
+ * powerpc code to implement the kexec_file_load syscall
  *
  * Copyright (C) 2004  Adam Litke ([e-mail])
  * Copyright (C) 2004  IBM Corp.
···
 #include <linux/libfdt.h>
 #include <asm/ima.h>
 
-#define SLAVE_CODE_SIZE		256
-
-const struct kexec_file_ops * const kexec_file_loaders[] = {
-	&kexec_elf64_ops,
-	NULL
-};
-
-int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
-				  unsigned long buf_len)
-{
-	/* We don't support crash kernels yet. */
-	if (image->type == KEXEC_TYPE_CRASH)
-		return -EOPNOTSUPP;
-
-	return kexec_image_probe_default(image, buf, buf_len);
-}
+#define SLAVE_CODE_SIZE		256	/* First 0x100 bytes */
 
 /**
  * setup_purgatory - initialize the purgatory's global variables

arch/powerpc/kexec/file_load_64.c

···
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ppc64 code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004  Adam Litke ([e-mail])
+ * Copyright (C) 2004  IBM Corp.
+ * Copyright (C) 2004,2005  Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005  R Sharada ([e-mail])
+ * Copyright (C) 2006  Mohan Kumar M ([e-mail])
+ * Copyright (C) 2020  IBM Corporation
+ *
+ * Based on kexec-tools' kexec-ppc64.c, kexec-elf-rel-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Hari Bathini, IBM Corporation.
+ */
+
+#include <linux/kexec.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+	&kexec_elf64_ops,
+	NULL
+};
+
+/**
+ * setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
+ *                         variables and call setup_purgatory() to initialize
+ *                         common global variable.
+ * @image:                 kexec image.
+ * @slave_code:            Slave code for the purgatory.
+ * @fdt:                   Flattened device tree for the next kernel.
+ * @kernel_load_addr:      Address where the kernel is loaded.
+ * @fdt_load_addr:         Address where the flattened device tree is loaded.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
+			  const void *fdt, unsigned long kernel_load_addr,
+			  unsigned long fdt_load_addr)
+{
+	int ret;
+
+	ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
+			      fdt_load_addr);
+	if (ret)
+		pr_err("Failed to setup purgatory symbols");
+	return ret;
+}
+
+/**
+ * setup_new_fdt_ppc64 - Update the flattend device-tree of the kernel
+ *                       being loaded.
+ * @image:               kexec image being loaded.
+ * @fdt:                 Flattened device tree for the next kernel.
+ * @initrd_load_addr:    Address where the next initrd will be loaded.
+ * @initrd_len:          Size of the next initrd, or 0 if there will be none.
+ * @cmdline:             Command line for the next kernel, or NULL if there will
+ *                       be none.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
+			unsigned long initrd_load_addr,
+			unsigned long initrd_len, const char *cmdline)
+{
+	return setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
+}
+
+/**
+ * arch_kexec_kernel_image_probe - Does additional handling needed to setup
+ *                                 kexec segments.
+ * @image:                         kexec image being loaded.
+ * @buf:                           Buffer pointing to elf data.
+ * @buf_len:                       Length of the buffer.
+ *
+ * Returns 0 on success, negative errno on error.
+ */
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+				  unsigned long buf_len)
+{
+	/* We don't support crash kernels yet. */
+	if (image->type == KEXEC_TYPE_CRASH)
+		return -EOPNOTSUPP;
+
+	return kexec_image_probe_default(image, buf, buf_len);
+}

arch/powerpc/purgatory/Makefile

···
 
 KASAN_SANITIZE := n
 
-targets += trampoline.o purgatory.ro kexec-purgatory.c
+targets += trampoline_$(BITS).o purgatory.ro kexec-purgatory.c
 
 LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined
 
-$(obj)/purgatory.ro: $(obj)/trampoline.o FORCE
+$(obj)/purgatory.ro: $(obj)/trampoline_$(BITS).o FORCE
 		$(call if_changed,ld)
 
 quiet_cmd_bin2c = BIN2C   $@