| Message ID | 5241D9F2.80908@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Wed, Sep 25, 2013 at 02:29:06AM +0800, Zhang Yanfei wrote: > +/** > + * memory_map_top_down - Map [map_start, map_end) top down > + * @map_start: start address of the target memory range > + * @map_end: end address of the target memory range > + * > + * This function will setup direct mapping for memory range > + * [map_start, map_end) in top-down. Can you please put a bit more effort into the function description? Other than that, Acked-by: Tejun Heo <tj@kernel.org> Thanks.
On 09/26/2013 10:46 PM, Tejun Heo wrote: > On Wed, Sep 25, 2013 at 02:29:06AM +0800, Zhang Yanfei wrote: >> +/** >> + * memory_map_top_down - Map [map_start, map_end) top down >> + * @map_start: start address of the target memory range >> + * @map_end: end address of the target memory range >> + * >> + * This function will setup direct mapping for memory range >> + * [map_start, map_end) in top-down. > > Can you please put a bit more effort into the function description? Sorry.... I will try to make a more detailed description. > > Other than that, > > Acked-by: Tejun Heo <tj@kernel.org> Thanks.
Hello tejun, On 09/26/2013 11:39 PM, Zhang Yanfei wrote: > On 09/26/2013 10:46 PM, Tejun Heo wrote: >> On Wed, Sep 25, 2013 at 02:29:06AM +0800, Zhang Yanfei wrote: >>> +/** >>> + * memory_map_top_down - Map [map_start, map_end) top down >>> + * @map_start: start address of the target memory range >>> + * @map_end: end address of the target memory range >>> + * >>> + * This function will setup direct mapping for memory range >>> + * [map_start, map_end) in top-down. >> >> Can you please put a bit more effort into the function description? > > Sorry.... I will try to make a more detailed description. Trying below: /** * memory_map_top_down - Map [map_start, map_end) top down * @map_start: start address of the target memory range * @map_end: end address of the target memory range * * This function will setup direct mapping for memory range * [map_start, map_end) in top-down. That said, the page tables * will be allocated at the end of the memory, and we map the * memory top-down. */ static void __init memory_map_top_down(unsigned long map_start, unsigned long map_end) { Thanks. > >> >> Other than that, >> >> Acked-by: Tejun Heo <tj@kernel.org> > > Thanks. >
On Wed, 2013-09-25 at 02:29 +0800, Zhang Yanfei wrote: > From: Tang Chen <tangchen@cn.fujitsu.com> > > This patch creates a new function memory_map_top_down to > factor out of the top-down direct memory mapping pagetable > setup. This is also a preparation for the following patch, > which will introduce the bottom-up memory mapping. That said, > we will put the two ways of pagetable setup into separate > functions, and choose to use which way in init_mem_mapping, > which makes the code more clear. > > Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> > Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 04664cd..dbe57e5 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -401,27 +401,26 @@ static unsigned long __init init_range_memory_mapping( /* (PUD_SHIFT-PMD_SHIFT)/2 */ #define STEP_SIZE_SHIFT 5 -void __init init_mem_mapping(void) + +/** + * memory_map_top_down - Map [map_start, map_end) top down + * @map_start: start address of the target memory range + * @map_end: end address of the target memory range + * + * This function will setup direct mapping for memory range + * [map_start, map_end) in top-down. + */ +static void __init memory_map_top_down(unsigned long map_start, + unsigned long map_end) { - unsigned long end, real_end, start, last_start; + unsigned long real_end, start, last_start; unsigned long step_size; unsigned long addr; unsigned long mapped_ram_size = 0; unsigned long new_mapped_ram_size; - probe_page_size_mask(); - -#ifdef CONFIG_X86_64 - end = max_pfn << PAGE_SHIFT; -#else - end = max_low_pfn << PAGE_SHIFT; -#endif - - /* the ISA range is always mapped regardless of memory holes */ - init_memory_mapping(0, ISA_END_ADDRESS); - /* xen has big range in reserved near end of ram, skip it at first.*/ - addr = memblock_find_in_range(ISA_END_ADDRESS, end, PMD_SIZE, PMD_SIZE); + addr = memblock_find_in_range(map_start, map_end, PMD_SIZE, PMD_SIZE); real_end = addr + PMD_SIZE; /* step_size need to be small so pgt_buf from BRK could cover it */ @@ -436,13 +435,13 @@ void __init init_mem_mapping(void) * end of RAM in [min_pfn_mapped, max_pfn_mapped) used as new pages * for page table. */ - while (last_start > ISA_END_ADDRESS) { + while (last_start > map_start) { if (last_start > step_size) { start = round_down(last_start - 1, step_size); - if (start < ISA_END_ADDRESS) - start = ISA_END_ADDRESS; + if (start < map_start) + start = map_start; } else - start = ISA_END_ADDRESS; + start = map_start; new_mapped_ram_size = init_range_memory_mapping(start, last_start); last_start = start; @@ -453,8 +452,27 @@ void __init init_mem_mapping(void) mapped_ram_size += new_mapped_ram_size; } - if (real_end < end) - init_range_memory_mapping(real_end, end); + if (real_end < map_end) + init_range_memory_mapping(real_end, map_end); +} + +void __init init_mem_mapping(void) +{ + unsigned long end; + + probe_page_size_mask(); + +#ifdef CONFIG_X86_64 + end = max_pfn << PAGE_SHIFT; +#else + end = max_low_pfn << PAGE_SHIFT; +#endif + + /* the ISA range is always mapped regardless of memory holes */ + init_memory_mapping(0, ISA_END_ADDRESS); + + /* setup direct mapping for range [ISA_END_ADDRESS, end) in top-down*/ + memory_map_top_down(ISA_END_ADDRESS, end); #ifdef CONFIG_X86_64 if (max_pfn > max_low_pfn) {