Some code refactor in kaslr_legal_offset() and kaslr_early_init(). No
functional change. This is a preparation for KASLR fsl_booke64.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Cc: Scott Wood <oss@buserror.net>
Cc: Diana Craciun <redacted>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <redacted>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Kees Cook <redacted>
---
  arch/powerpc/mm/nohash/kaslr_booke.c | 40 ++++++++++++++--------------
  1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/arch/powerpc/mm/nohash/kaslr_booke.c b/arch/powerpc/mm/nohash/kaslr_booke.c
index 4a75f2d9bf0e..07b036e98353 100644
--- a/arch/powerpc/mm/nohash/kaslr_booke.c
+++ b/arch/powerpc/mm/nohash/kaslr_booke.c

@@ -25,6 +25,7 @@ struct regions {
  	unsigned long pa_start;
  	unsigned long pa_end;
  	unsigned long kernel_size;
+	unsigned long linear_sz;
  	unsigned long dtb_start;
  	unsigned long dtb_end;
  	unsigned long initrd_start;

@@ -260,11 +261,23 @@ static __init void get_cell_sizes(const void *fdt, int node, int *addr_cells,
  		*size_cells = fdt32_to_cpu(*prop);
  }
  
-static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long index,
-					       unsigned long offset)
+static unsigned long __init kaslr_legal_offset(void *dt_ptr, unsigned long random)
  {
  	unsigned long koffset = 0;
  	unsigned long start;
+	unsigned long index;
+	unsigned long offset;
+
+	/*
+	 * Decide which 64M we want to start
+	 * Only use the low 8 bits of the random seed
+	 */
+	index = random & 0xFF;
+	index %= regions.linear_sz / SZ_64M;
+
+	/* Decide offset inside 64M */
+	offset = random % (SZ_64M - regions.kernel_size);
+	offset = round_down(offset, SZ_16K);
  
  	while ((long)index >= 0) {
  		offset = memstart_addr + index * SZ_64M + offset;

@@ -289,10 +302,9 @@ static inline __init bool kaslr_disabled(void)
  static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size,
  						  unsigned long kernel_sz)
  {
-	unsigned long offset, random;
+	unsigned long random;
  	unsigned long ram, linear_sz;
  	u64 seed;
-	unsigned long index;
  
  	kaslr_get_cmdline(dt_ptr);
  	if (kaslr_disabled())

@@ -333,22 +345,12 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size
  	regions.dtb_start = __pa(dt_ptr);
  	regions.dtb_end = __pa(dt_ptr) + fdt_totalsize(dt_ptr);
  	regions.kernel_size = kernel_sz;
+	regions.linear_sz = linear_sz;
  
  	get_initrd_range(dt_ptr);
  	get_crash_kernel(dt_ptr, ram);
  
-	/*
-	 * Decide which 64M we want to start
-	 * Only use the low 8 bits of the random seed
-	 */
-	index = random & 0xFF;
-	index %= linear_sz / SZ_64M;
-
-	/* Decide offset inside 64M */
-	offset = random % (SZ_64M - kernel_sz);
-	offset = round_down(offset, SZ_16K);
-
-	return kaslr_legal_offset(dt_ptr, index, offset);
+	return kaslr_legal_offset(dt_ptr, random);
  }
  
  /*

@@ -358,8 +360,6 @@ static unsigned long __init kaslr_choose_location(void *dt_ptr, phys_addr_t size
   */
  notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size)
  {
-	unsigned long tlb_virt;
-	phys_addr_t tlb_phys;
  	unsigned long offset;
  	unsigned long kernel_sz;
  

@@ -375,8 +375,8 @@ notrace void __init kaslr_early_init(void *dt_ptr, phys_addr_t size)
  	is_second_reloc = 1;
  
  	if (offset >= SZ_64M) {
-		tlb_virt = round_down(kernstart_virt_addr, SZ_64M);
-		tlb_phys = round_down(kernstart_addr, SZ_64M);
+		unsigned long tlb_virt = round_down(kernstart_virt_addr, SZ_64M);
+		phys_addr_t tlb_phys = round_down(kernstart_addr, SZ_64M);