x86/boot/e820: Document e820__reserve_setup_data()

Also clean it up a bit.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/include/asm/e820/api.h

@@ -22,10 +22,10 @@ extern void e820__update_table_print(void);
 extern unsigned long e820_end_of_ram_pfn(void);
 extern unsigned long e820_end_of_low_ram_pfn(void);
 
-extern u64  e820__memblock_alloc_reserved(u64 sizet, u64 align);
+extern u64  e820__memblock_alloc_reserved(u64 size, u64 align);
 extern void e820__memblock_setup(void);
 
-extern void e820_reserve_setup_data(void);
+extern void e820__reserve_setup_data(void);
 extern void e820__finish_early_params(void);
 extern void e820_reserve_resources(void);
 extern void e820_reserve_resources_late(void);

arch/x86/kernel/e820.c

@@ -922,7 +922,12 @@ static int __init parse_memmap_opt(char *str)
 }
 early_param("memmap", parse_memmap_opt);
 
-void __init e820_reserve_setup_data(void)
+/*
+ * Reserve all entries from the bootloader's extensible data nodes list,
+ * because if present we are going to use it later on to fetch e820
+ * entries from it:
+ */
+void __init e820__reserve_setup_data(void)
 {
 	struct setup_data *data;
 	u64 pa_data;
@@ -939,8 +944,10 @@ void __init e820_reserve_setup_data(void)
 	}
 
 	e820__update_table(e820_table);
+
 	memcpy(e820_table_firmware, e820_table, sizeof(*e820_table_firmware));
-	printk(KERN_INFO "extended physical RAM map:\n");
+
+	pr_info("extended physical RAM map:\n");
 	e820__print_table("reserve setup_data");
 }
 

arch/x86/kernel/setup.c

@@ -1003,8 +1003,7 @@ void __init setup_arch(char **cmdline_p)
 		early_dump_pci_devices();
 #endif
 
-	/* update the e820_table_firmware too */
-	e820_reserve_setup_data();
+	e820__reserve_setup_data();
 	e820__finish_early_params();
 
 	if (efi_enabled(EFI_BOOT))