Do some common-sense cleanups: - standardize on the kernel coding style consistently
- tabulate definitions consistently - extend and clarify various descriptions - fix speling - update the header guard name according to the new position - etc. No change in functionality. Cc: Alex Thorlton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dan Williams <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Huang, Ying <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul Jackson <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rafael J. Wysocki <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Wei Yang <[email protected]> Cc: Yinghai Lu <[email protected]> Cc: [email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/include/asm/e820/types.h | 84 +++++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 53 insertions(+), 31 deletions(-) diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h index 9dafe59cf6e2..cfa8f4a19b5d 100644 --- a/arch/x86/include/asm/e820/types.h +++ b/arch/x86/include/asm/e820/types.h @@ -1,18 +1,30 @@ -#ifndef _UAPI_ASM_X86_E820_H -#define _UAPI_ASM_X86_E820_H -#define E820MAP 0x2d0 /* our map */ -#define E820MAX 128 /* number of entries in E820MAP */ +#ifndef _ASM_E820_TYPES_H +#define _ASM_E820_TYPES_H + +/* Our map: */ +#define E820MAP 0x2d0 + +/* The maximum number of entries in E820MAP: */ +#define E820MAX 128 /* - * Legacy E820 BIOS limits us to 128 (E820MAX) nodes due to the - * constrained space in the zeropage. If we have more nodes than - * that, and if we've booted off EFI firmware, then the EFI tables - * passed us from the EFI firmware can list more nodes. Size our - * internal memory map tables to have room for these additional - * nodes, based on up to three entries per node for which the - * kernel was built: MAX_NUMNODES == (1 << CONFIG_NODES_SHIFT), - * plus E820MAX, allowing space for the possible duplicate E820 - * entries that might need room in the same arrays, prior to the + * The legacy E820 BIOS limits us to 128 (E820MAX) nodes due to the + * constrained space in the zeropage. + * + * On large systems we can easily have thousands of nodes with RAM, + * which cannot be fit into so few entries - so we have a mechanism + * to extend the e820 table size at build-time, via the E820_X_MAX + * define below. + * + * ( Those extra entries are enumerated via the EFI memory map, not + * via the legacy zeropage mechanism. ) + * + * Size our internal memory map tables to have room for these additional + * entries, based on a heuristic calculation: up to three entries per + * NUMA node, plus E820MAX for some extra space. + * + * This allows for bootstrap/firmware quirks such as possible duplicate + * E820 entries that might need room in the same arrays, prior to the * call to sanitize_e820_map() to remove duplicates. The allowance * of three memory map entries per node is "enough" entries for * the initial hardware platform motivating this mechanism to make @@ -20,19 +32,19 @@ * to allow more than three entries per node or otherwise refine * this size. */ - #ifndef __KERNEL__ -#define E820_X_MAX E820MAX +# define E820_X_MAX E820MAX #endif -#define E820NR 0x1e8 /* # entries in E820MAP */ +/* Number of entries in E820MAP: */ +#define E820NR 0x1e8 -#define E820_RAM 1 -#define E820_RESERVED 2 -#define E820_ACPI 3 -#define E820_NVS 4 -#define E820_UNUSABLE 5 -#define E820_PMEM 7 +#define E820_RAM 1 +#define E820_RESERVED 2 +#define E820_ACPI 3 +#define E820_NVS 4 +#define E820_UNUSABLE 5 +#define E820_PMEM 7 /* * This is a non-standardized way to represent ADR or NVDIMM regions that @@ -43,7 +55,7 @@ * but newer versions switched to 12 as 6 was assigned differently. Some * time they will learn... ) */ -#define E820_PRAM 12 +#define E820_PRAM 12 /* * reserved RAM used by kernel itself @@ -51,23 +63,34 @@ * included in the S3 integrity calculation and so should not include * any memory that BIOS might alter over the S3 transition */ -#define E820_RESERVED_KERN 128 +#define E820_RESERVED_KERN 128 #ifndef __ASSEMBLY__ #include <linux/types.h> + +/* + * A single E820 map entry, describing a memory range of [addr...addr+size-1], + * of 'type' memory type: + */ struct e820entry { - __u64 addr; /* start of memory segment */ - __u64 size; /* size of memory segment */ - __u32 type; /* type of memory segment */ + __u64 addr; + __u64 size; + __u32 type; } __attribute__((packed)); +/* + * The whole array of E820 entries: + */ struct e820map { __u32 nr_map; struct e820entry map[E820_X_MAX]; }; -#define ISA_START_ADDRESS 0xa0000 -#define ISA_END_ADDRESS 0x100000 +/* + * Various legacy ranges in physical memory: + */ +#define ISA_START_ADDRESS 0x000a0000 +#define ISA_END_ADDRESS 0x00100000 #define BIOS_BEGIN 0x000a0000 #define BIOS_END 0x00100000 @@ -77,5 +100,4 @@ struct e820map { #endif /* __ASSEMBLY__ */ - -#endif /* _UAPI_ASM_X86_E820_H */ +#endif /* _ASM_E820_TYPES_H */ -- 2.7.4
