x86/boot/64: Rename init_level4_pgt and early_level4_pgt

With CONFIG_X86_5LEVEL=y, level 4 is no longer top level of page tables.

Let's give these variable more generic names: init_top_pgt and
early_top_pgt.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-9-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/espfix_64.c

@@ -125,7 +125,7 @@ void __init init_espfix_bsp(void)
 	p4d_t *p4d;
 
 	/* Install the espfix pud into the kernel page directory */
-	pgd = &init_level4_pgt[pgd_index(ESPFIX_BASE_ADDR)];
+	pgd = &init_top_pgt[pgd_index(ESPFIX_BASE_ADDR)];
 	p4d = p4d_alloc(&init_mm, pgd, ESPFIX_BASE_ADDR);
 	p4d_populate(&init_mm, p4d, espfix_pud_page);
 

arch/x86/kernel/head64.c

@@ -33,7 +33,7 @@
 /*
  * Manage page tables very early on.
  */
-extern pgd_t early_level4_pgt[PTRS_PER_PGD];
+extern pgd_t early_top_pgt[PTRS_PER_PGD];
 extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
 static unsigned int __initdata next_early_pgt;
 pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX);
@@ -67,7 +67,7 @@ void __init __startup_64(unsigned long physaddr)
 
 	/* Fixup the physical addresses in the page table */
 
-	pgd = fixup_pointer(&early_level4_pgt, physaddr);
+	pgd = fixup_pointer(&early_top_pgt, physaddr);
 	pgd[pgd_index(__START_KERNEL_map)] += load_delta;
 
 	pud = fixup_pointer(&level3_kernel_pgt, physaddr);
@@ -124,9 +124,9 @@ void __init __startup_64(unsigned long physaddr)
 /* Wipe all early page tables except for the kernel symbol map */
 static void __init reset_early_page_tables(void)
 {
-	memset(early_level4_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
+	memset(early_top_pgt, 0, sizeof(pgd_t)*(PTRS_PER_PGD-1));
 	next_early_pgt = 0;
-	write_cr3(__pa_nodebug(early_level4_pgt));
+	write_cr3(__pa_nodebug(early_top_pgt));
 }
 
 /* Create a new PMD entry */
@@ -138,12 +138,11 @@ int __init early_make_pgtable(unsigned long address)
 	pmdval_t pmd, *pmd_p;
 
 	/* Invalid address or early pgt is done ?  */
-	if (physaddr >= MAXMEM ||
-	    read_cr3_pa() != __pa_nodebug(early_level4_pgt))
+	if (physaddr >= MAXMEM || read_cr3_pa() != __pa_nodebug(early_top_pgt))
 		return -1;
 
 again:
-	pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
+	pgd_p = &early_top_pgt[pgd_index(address)].pgd;
 	pgd = *pgd_p;
 
 	/*
@@ -240,7 +239,7 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
 
 	clear_bss();
 
-	clear_page(init_level4_pgt);
+	clear_page(init_top_pgt);
 
 	kasan_early_init();
 
@@ -255,8 +254,8 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)
 	 */
 	load_ucode_bsp();
 
-	/* set init_level4_pgt kernel high mapping*/
-	init_level4_pgt[511] = early_level4_pgt[511];
+	/* set init_top_pgt kernel high mapping*/
+	init_top_pgt[511] = early_top_pgt[511];
 
 	x86_64_start_reservations(real_mode_data);
 }

arch/x86/kernel/head_64.S

@@ -77,7 +77,7 @@ startup_64:
 	call	__startup_64
 	popq	%rsi
 
-	movq	$(early_level4_pgt - __START_KERNEL_map), %rax
+	movq	$(early_top_pgt - __START_KERNEL_map), %rax
 	jmp 1f
 ENTRY(secondary_startup_64)
 	/*
@@ -97,7 +97,7 @@ ENTRY(secondary_startup_64)
 	/* Sanitize CPU configuration */
 	call verify_cpu
 
-	movq	$(init_level4_pgt - __START_KERNEL_map), %rax
+	movq	$(init_top_pgt - __START_KERNEL_map), %rax
 1:
 
 	/* Enable PAE mode and PGE */
@@ -328,7 +328,7 @@ GLOBAL(name)
 	.endr
 
 	__INITDATA
-NEXT_PAGE(early_level4_pgt)
+NEXT_PAGE(early_top_pgt)
 	.fill	511,8,0
 	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
 
@@ -338,14 +338,14 @@ NEXT_PAGE(early_dynamic_pgts)
 	.data
 
 #ifndef CONFIG_XEN
-NEXT_PAGE(init_level4_pgt)
+NEXT_PAGE(init_top_pgt)
 	.fill	512,8,0
 #else
-NEXT_PAGE(init_level4_pgt)
+NEXT_PAGE(init_top_pgt)
 	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.org    init_level4_pgt + L4_PAGE_OFFSET*8, 0
+	.org    init_top_pgt + L4_PAGE_OFFSET*8, 0
 	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.org    init_level4_pgt + L4_START_KERNEL*8, 0
+	.org    init_top_pgt + L4_START_KERNEL*8, 0
 	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
 	.quad   level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
 

arch/x86/kernel/machine_kexec_64.c

@@ -347,7 +347,7 @@ void machine_kexec(struct kimage *image)
 void arch_crash_save_vmcoreinfo(void)
 {
 	VMCOREINFO_NUMBER(phys_base);
-	VMCOREINFO_SYMBOL(init_level4_pgt);
+	VMCOREINFO_SYMBOL(init_top_pgt);
 
 #ifdef CONFIG_NUMA
 	VMCOREINFO_SYMBOL(node_data);