riscv: Mark some global variables __ro_after_init

All of these are never modified after init, so they can be
__ro_after_init.
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

arch/riscv/kernel/sbi.c

@@ -11,14 +11,14 @@
 #include <asm/smp.h>
 
 /* default SBI version is 0.1 */
-unsigned long sbi_spec_version = SBI_SPEC_VERSION_DEFAULT;
+unsigned long sbi_spec_version __ro_after_init = SBI_SPEC_VERSION_DEFAULT;
 EXPORT_SYMBOL(sbi_spec_version);
 
-static void (*__sbi_set_timer)(uint64_t stime);
-static int (*__sbi_send_ipi)(const unsigned long *hart_mask);
+static void (*__sbi_set_timer)(uint64_t stime) __ro_after_init;
+static int (*__sbi_send_ipi)(const unsigned long *hart_mask) __ro_after_init;
 static int (*__sbi_rfence)(int fid, const unsigned long *hart_mask,
 			   unsigned long start, unsigned long size,
-			   unsigned long arg4, unsigned long arg5);
+			   unsigned long arg4, unsigned long arg5) __ro_after_init;
 
 struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
 			unsigned long arg1, unsigned long arg2,

arch/riscv/kernel/smp.c

@@ -32,7 +32,7 @@ enum ipi_message_type {
 	IPI_MAX
 };
 
-unsigned long __cpuid_to_hartid_map[NR_CPUS] = {
+unsigned long __cpuid_to_hartid_map[NR_CPUS] __ro_after_init = {
 	[0 ... NR_CPUS-1] = INVALID_HARTID
 };
 
@@ -87,7 +87,7 @@ static void ipi_stop(void)
 		wait_for_interrupt();
 }
 
-static struct riscv_ipi_ops *ipi_ops;
+static struct riscv_ipi_ops *ipi_ops __ro_after_init;
 
 void riscv_set_ipi_ops(struct riscv_ipi_ops *ops)
 {

arch/riscv/kernel/time.c

@@ -10,7 +10,7 @@
 #include <asm/sbi.h>
 #include <asm/processor.h>
 
-unsigned long riscv_timebase;
+unsigned long riscv_timebase __ro_after_init;
 EXPORT_SYMBOL_GPL(riscv_timebase);
 
 void __init time_init(void)

arch/riscv/kernel/vdso.c

@@ -20,8 +20,8 @@
 
 extern char vdso_start[], vdso_end[];
 
-static unsigned int vdso_pages;
-static struct page **vdso_pagelist;
+static unsigned int vdso_pages __ro_after_init;
+static struct page **vdso_pagelist __ro_after_init;
 
 /*
  * The vDSO data page.

arch/riscv/mm/init.c

@@ -162,17 +162,17 @@ void __init setup_bootmem(void)
 }
 
 #ifdef CONFIG_MMU
-static struct pt_alloc_ops pt_ops;
+static struct pt_alloc_ops pt_ops __ro_after_init;
 
 /* Offset between linear mapping virtual address and kernel load address */
-unsigned long va_pa_offset;
+unsigned long va_pa_offset __ro_after_init;
 EXPORT_SYMBOL(va_pa_offset);
 #ifdef CONFIG_64BIT
 /* Offset between kernel mapping virtual address and kernel load address */
 unsigned long va_kernel_pa_offset;
 EXPORT_SYMBOL(va_kernel_pa_offset);
 #endif
-unsigned long pfn_base;
+unsigned long pfn_base __ro_after_init;
 EXPORT_SYMBOL(pfn_base);
 
 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;