powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up
and freeing the resources required to carry over the IMA measurement
list from the current kernel to the next kernel across kexec system call.
These functions do not have architecture specific code, but are
currently limited to powerpc.

Move remove_ima_buffer() and setup_ima_buffer() calls into
of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".

Move the remaining architecture independent functions from
"arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c".
Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h".
Remove references to the deleted files and functions in powerpc and
in ima.

Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Tested-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210221174930.27324-11-nramas@linux.microsoft.com

arch/powerpc/include/asm/kexec.h

@@ -115,9 +115,6 @@ char *setup_kdump_cmdline(struct kimage *image, char *cmdline,
 int setup_purgatory(struct kimage *image, const void *slave_code,
 		    const void *fdt, unsigned long kernel_load_addr,
 		    unsigned long fdt_load_addr);
-int setup_new_fdt(const struct kimage *image, void *fdt,
-		  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

arch/powerpc/kexec/Makefile

@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32)		+= relocate_32.o
 
 obj-$(CONFIG_KEXEC_FILE)	+= file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
 
-ifdef CONFIG_HAVE_IMA_KEXEC
-ifdef CONFIG_IMA
-obj-y				+= ima.o
-endif
-endif
-
-
 # Disable GCOV, KCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_core_$(BITS).o := n
 KCOV_INSTRUMENT_core_$(BITS).o := n

arch/powerpc/kexec/file_load.c

@@ -19,7 +19,6 @@
 #include <linux/of_fdt.h>
 #include <linux/libfdt.h>
 #include <asm/setup.h>
-#include <asm/ima.h>
 
 #define SLAVE_CODE_SIZE		256	/* First 0x100 bytes */
 
@@ -140,27 +139,3 @@ int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size)
 
 	return -ENOENT;
 }
-
-/*
- * setup_new_fdt - modify /chosen and memory reservation for the next kernel
- * @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.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_new_fdt(const struct kimage *image, void *fdt,
-		  unsigned long initrd_load_addr, unsigned long initrd_len,
-		  const char *cmdline)
-{
-	int ret;
-
-	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
-	if (ret)
-		pr_err("Error setting up the new device tree.\n");
-
-	return ret;
-}

arch/powerpc/kexec/file_load_64.c

@@ -979,10 +979,6 @@ int setup_new_fdt_ppc64(const struct kimage *image, void *fdt,
 	struct crash_mem *umem = NULL, *rmem = NULL;
 	int i, nr_ranges, ret;
 
-	ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
-	if (ret)
-		goto out;
-
 	/*
 	 * Restrict memory usage for kdump kernel by setting up
 	 * usable memory ranges and memory reserve map.