From: Vivek Goyal - 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: Murali M Chakravarthy Signed-off-by: Hariprasad Nellitheertha Signed-off-by: Vivek Goyal Cc: Andi Kleen Signed-off-by: Andrew Morton --- Documentation/kernel-parameters.txt | 2 +- arch/x86_64/kernel/e820.c | 21 +++++++++++++++++++++ arch/x86_64/kernel/setup.c | 27 +++++++++++++++++++++++++++ include/asm-x86_64/e820.h | 1 + 4 files changed, 50 insertions(+), 1 deletion(-) diff -puN arch/x86_64/kernel/e820.c~kdump-x86_64-add-memmmap-command-line-option arch/x86_64/kernel/e820.c --- devel/arch/x86_64/kernel/e820.c~kdump-x86_64-add-memmmap-command-line-option 2005-12-22 05:09:30.000000000 -0800 +++ devel-akpm/arch/x86_64/kernel/e820.c 2005-12-22 05:09:30.000000000 -0800 @@ -559,6 +559,27 @@ void __init parse_memopt(char *p, char * 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; /* diff -puN arch/x86_64/kernel/setup.c~kdump-x86_64-add-memmmap-command-line-option arch/x86_64/kernel/setup.c --- devel/arch/x86_64/kernel/setup.c~kdump-x86_64-add-memmmap-command-line-option 2005-12-22 05:09:30.000000000 -0800 +++ devel-akpm/arch/x86_64/kernel/setup.c 2005-12-22 05:09:30.000000000 -0800 @@ -276,6 +276,7 @@ static __init void parse_cmdline_early ( { 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); @@ -355,6 +356,28 @@ static __init void parse_cmdline_early ( 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); @@ -401,6 +424,10 @@ static __init void parse_cmdline_early ( break; *(to++) = c; } + if (userdef) { + printk(KERN_INFO "user-defined physical RAM map:\n"); + e820_print_map("user"); + } *to = '\0'; *cmdline_p = command_line; } diff -puN Documentation/kernel-parameters.txt~kdump-x86_64-add-memmmap-command-line-option Documentation/kernel-parameters.txt --- devel/Documentation/kernel-parameters.txt~kdump-x86_64-add-memmmap-command-line-option 2005-12-22 05:09:30.000000000 -0800 +++ devel-akpm/Documentation/kernel-parameters.txt 2005-12-22 05:09:30.000000000 -0800 @@ -837,7 +837,7 @@ 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 diff -puN include/asm-x86_64/e820.h~kdump-x86_64-add-memmmap-command-line-option include/asm-x86_64/e820.h --- devel/include/asm-x86_64/e820.h~kdump-x86_64-add-memmmap-command-line-option 2005-12-22 05:09:30.000000000 -0800 +++ devel-akpm/include/asm-x86_64/e820.h 2005-12-22 05:09:30.000000000 -0800 @@ -55,6 +55,7 @@ extern unsigned long e820_hole_size(unsi 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__*/ _