x86/e820: Prepare e280 code for switch to dynamic storage

This patch turns e820 and e820_saved into pointers to e820 tables,
of the same size as before.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
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: 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: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20160917213927.1787-2-dvlasenk@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/e820.h

@@ -10,8 +10,8 @@
 #include <uapi/asm/e820.h>
 #ifndef __ASSEMBLY__
 /* see comment in arch/x86/kernel/e820.c */
-extern struct e820map e820;
-extern struct e820map e820_saved;
+extern struct e820map *e820;
+extern struct e820map *e820_saved;
 
 extern unsigned long pci_mem_start;
 extern int e820_any_mapped(u64 start, u64 end, unsigned type);
@@ -53,6 +53,8 @@ extern void e820_reserve_resources_late(void);
 extern void setup_memory_map(void);
 extern char *default_machine_specific_memory_setup(void);
 
+extern void e820_reallocate_tables(void);
+
 /*
  * Returns true iff the specified range [s,e) is completely contained inside
  * the ISA region.

arch/x86/kernel/early-quirks.c

@@ -555,7 +555,7 @@ intel_graphics_stolen(int num, int slot, int func,
 
 	/* Mark this space as reserved */
 	e820_add_region(base, size, E820_RESERVED);
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 }
 
 static void __init intel_graphics_quirks(int num, int slot, int func)

arch/x86/kernel/kexec-bzimage64.c

@@ -99,14 +99,14 @@ static int setup_e820_entries(struct boot_params *params)
 {
 	unsigned int nr_e820_entries;
 
-	nr_e820_entries = e820_saved.nr_map;
+	nr_e820_entries = e820_saved->nr_map;
 
 	/* TODO: Pass entries more than E820MAX in bootparams setup data */
 	if (nr_e820_entries > E820MAX)
 		nr_e820_entries = E820MAX;
 
 	params->e820_entries = nr_e820_entries;
-	memcpy(&params->e820_map, &e820_saved.map,
+	memcpy(&params->e820_map, &e820_saved->map,
 	       nr_e820_entries * sizeof(struct e820entry));
 
 	return 0;

arch/x86/kernel/resource.c

@@ -27,8 +27,8 @@ static void remove_e820_regions(struct resource *avail)
 	int i;
 	struct e820entry *entry;
 
-	for (i = 0; i < e820.nr_map; i++) {
-		entry = &e820.map[i];
+	for (i = 0; i < e820->nr_map; i++) {
+		entry = &e820->map[i];
 
 		resource_clip(avail, entry->addr,
 			      entry->addr + entry->size - 1);

arch/x86/kernel/setup.c

@@ -458,8 +458,8 @@ static void __init e820_reserve_setup_data(void)
 		early_memunmap(data, sizeof(*data));
 	}
 
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
-	memcpy(&e820_saved, &e820, sizeof(struct e820map));
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
+	memcpy(e820_saved, e820, sizeof(struct e820map));
 	printk(KERN_INFO "extended physical RAM map:\n");
 	e820_print_map("reserve setup_data");
 }
@@ -763,7 +763,7 @@ static void __init trim_bios_range(void)
 	 */
 	e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
 
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 }
 
 /* called before trim_bios_range() to spare extra sanitize */
@@ -1032,7 +1032,7 @@ void __init setup_arch(char **cmdline_p)
 	if (ppro_with_ram_bug()) {
 		e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
 				  E820_RESERVED);
-		sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+		sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 		printk(KERN_INFO "fixed physical RAM map:\n");
 		e820_print_map("bad_ppro");
 	}

arch/x86/kernel/tboot.c

@@ -188,12 +188,12 @@ static int tboot_setup_sleep(void)
 
 	tboot->num_mac_regions = 0;
 
-	for (i = 0; i < e820.nr_map; i++) {
-		if ((e820.map[i].type != E820_RAM)
-		 && (e820.map[i].type != E820_RESERVED_KERN))
+	for (i = 0; i < e820->nr_map; i++) {
+		if ((e820->map[i].type != E820_RAM)
+		 && (e820->map[i].type != E820_RESERVED_KERN))
 			continue;
 
-		add_mac_region(e820.map[i].addr, e820.map[i].size);
+		add_mac_region(e820->map[i].addr, e820->map[i].size);
 	}
 
 	tboot->acpi_sinfo.kernel_s3_resume_vector =

arch/x86/mm/init.c

@@ -701,6 +701,8 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end)
 
 void free_initmem(void)
 {
+	/* e820_reallocate_tables(); - disabled for now */
+
 	free_init_pages("unused kernel",
 			(unsigned long)(&__init_begin),
 			(unsigned long)(&__init_end));

arch/x86/platform/efi/efi.c

@@ -166,7 +166,7 @@ static void __init do_add_efi_memmap(void)
 		}
 		e820_add_region(start, size, e820_type);
 	}
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 }
 
 int __init efi_memblock_x86_reserve_range(void)

arch/x86/xen/setup.c

@@ -861,7 +861,7 @@ char * __init xen_memory_setup(void)
 	e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
 			E820_RESERVED);
 
-	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+	sanitize_e820_map(e820->map, ARRAY_SIZE(e820->map), &e820->nr_map);
 
 	/*
 	 * Check whether the kernel itself conflicts with the target E820 map.