Commit 69cda7b1 authored by akpm@osdl.org's avatar akpm@osdl.org Committed by Linus Torvalds
Browse files

[PATCH] kdump: x86_64: add memmmap command line option 




)

From: Vivek Goyal <vgoyal@in.ibm.com>

- This patch introduces the memmap option for x86_64 similar to i386.

- memmap=exactmap enables setting of an exact E820 memory map, as specified
  by the user.

Changes in this version:

- Used e820_end_of_ram() to find the max_pfn as suggested by Andi kleen.

- removed PFN_UP & PFN_DOWN macros

- Printing the user defined map also.

Signed-off-by: default avatarMurali M Chakravarthy <muralim@in.ibm.com>
Signed-off-by: default avatarHariprasad Nellitheertha <nharipra@gmail.com>
Signed-off-by: default avatarVivek Goyal <vgoyal@in.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent bf208305

Documentation/kernel-parameters.txt

+1 −1
Original line number Diff line number Diff line
@@ -832,7 +832,7 @@ running once the system is up. 
	mem=nopentium	[BUGS=IA-32] Disable usage of 4MB pages for kernel

			memory.



	memmap=exactmap	[KNL,IA-32] Enable setting of an exact

	memmap=exactmap	[KNL,IA-32,X86_64] Enable setting of an exact

			E820 memory map, as specified by the user.

			Such memmap=exactmap lines can be constructed based on

			BIOS output or other requirements. See the memmap=nn@ss

arch/x86_64/kernel/e820.c

+21 −0
Original line number Diff line number Diff line
@@ -559,6 +559,27 @@ void __init parse_memopt(char *p, char **from) 
	end_user_pfn >>= PAGE_SHIFT;	

} 



void __init parse_memmapopt(char *p, char **from)

{

	unsigned long long start_at, mem_size;



	mem_size = memparse(p, from);

	p = *from;

	if (*p == '@') {

		start_at = memparse(p+1, from);

		add_memory_region(start_at, mem_size, E820_RAM);

	} else if (*p == '#') {

		start_at = memparse(p+1, from);

		add_memory_region(start_at, mem_size, E820_ACPI);

	} else if (*p == '$') {

		start_at = memparse(p+1, from);

		add_memory_region(start_at, mem_size, E820_RESERVED);

	} else {

		end_user_pfn = (mem_size >> PAGE_SHIFT);

	}

	p = *from;

}



unsigned long pci_mem_start = 0xaeedbabe;



/*

arch/x86_64/kernel/setup.c

+27 −0
Original line number Diff line number Diff line
@@ -275,6 +275,7 @@ static __init void parse_cmdline_early (char ** cmdline_p) 
{

	char c = ' ', *to = command_line, *from = COMMAND_LINE;

	int len = 0;

	int userdef = 0;



	/* Save unparsed command line copy for /proc/cmdline */

	memcpy(saved_command_line, COMMAND_LINE, COMMAND_LINE_SIZE);
@@ -357,6 +358,28 @@ static __init void parse_cmdline_early (char ** cmdline_p) 
		if (!memcmp(from, "mem=", 4))

			parse_memopt(from+4, &from); 



		if (!memcmp(from, "memmap=", 7)) {

			/* exactmap option is for used defined memory */

			if (!memcmp(from+7, "exactmap", 8)) {

#ifdef CONFIG_CRASH_DUMP

				/* If we are doing a crash dump, we

				 * still need to know the real mem

				 * size before original memory map is

				 * reset.

				 */

				saved_max_pfn = e820_end_of_ram();

#endif

				from += 8+7;

				end_pfn_map = 0;

				e820.nr_map = 0;

				userdef = 1;

			}

			else {

				parse_memmapopt(from+7, &from);

				userdef = 1;

			}

		}



#ifdef CONFIG_NUMA

		if (!memcmp(from, "numa=", 5))

			numa_setup(from+5);
@@ -403,6 +426,10 @@ static __init void parse_cmdline_early (char ** cmdline_p) 
			break;

		*(to++) = c;

	}

	if (userdef) {

		printk(KERN_INFO "user-defined physical RAM map:\n");

		e820_print_map("user");

	}

	*to = '\0';

	*cmdline_p = command_line;

}

include/asm-x86_64/e820.h

+1 −0
Original line number Diff line number Diff line
@@ -55,6 +55,7 @@ extern unsigned long e820_hole_size(unsigned long start_pfn, 
				    unsigned long end_pfn);



extern void __init parse_memopt(char *p, char **end);

extern void __init parse_memmapopt(char *p, char **end);



extern struct e820map e820;

#endif/*!__ASSEMBLY__*/

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