Restore the x86-64 support for memory hotplug in the context of sparsemem. This arch specific patch includes the [add,remove]_memory and online functions as well as the kernel page table initialization changes necessary to map new memory should it be added at runtime. Also, allow for sparsemem to be an available option to single node memory hotplug kernels, by removing the strict dependency on CONFIG_NUMA. Signed-off-by: Matt Tolentino Signed-off-by: Dave Hansen --- include/asm-x86_64/mman.h | 0 memhotplug-dave/arch/x86_64/Kconfig | 1 memhotplug-dave/arch/x86_64/mm/init.c | 193 ++++++++++++++++++++++++++++------ 3 files changed, 161 insertions(+), 33 deletions(-) diff -puN arch/x86_64/Kconfig~L4-x86-64-memory-hotplug-no-sparse arch/x86_64/Kconfig --- memhotplug/arch/x86_64/Kconfig~L4-x86-64-memory-hotplug-no-sparse 2005-04-13 14:21:13.000000000 -0700 +++ memhotplug-dave/arch/x86_64/Kconfig 2005-04-13 14:21:13.000000000 -0700 @@ -286,7 +286,6 @@ config ARCH_DISCONTIGMEM_DEFAULT config ARCH_SPARSEMEM_ENABLE def_bool y - depends on NUMA config ARCH_FLATMEM_DISABLE def_bool y diff -puN arch/x86_64/mm/init.c~L4-x86-64-memory-hotplug-no-sparse arch/x86_64/mm/init.c --- memhotplug/arch/x86_64/mm/init.c~L4-x86-64-memory-hotplug-no-sparse 2005-04-13 14:21:13.000000000 -0700 +++ memhotplug-dave/arch/x86_64/mm/init.c 2005-04-13 14:21:13.000000000 -0700 @@ -22,6 +22,8 @@ #include #include #include +#include +#include #include #include @@ -179,13 +181,19 @@ static struct temp_map { {} }; -static __init void *alloc_low_page(int *index, unsigned long *phys) +static __devinit void *alloc_low_page(int *index, unsigned long *phys) { struct temp_map *ti; int i; unsigned long pfn = table_end++, paddr; void *adr; + if (after_bootmem) { + adr = (void *)get_zeroed_page(GFP_ATOMIC); + *phys = __pa(adr); + return adr; + } + if (pfn >= end_pfn) panic("alloc_low_page: ran out of memory"); for (i = 0; temp_mappings[i].allocated; i++) { @@ -198,55 +206,95 @@ static __init void *alloc_low_page(int * ti->allocated = 1; __flush_tlb(); adr = ti->address + ((pfn << PAGE_SHIFT) & ~PMD_MASK); + memset(adr, 0, PAGE_SIZE); *index = i; *phys = pfn * PAGE_SIZE; return adr; } -static __init void unmap_low_page(int i) +static __devinit void unmap_low_page(int i) { - struct temp_map *ti = &temp_mappings[i]; + struct temp_map *ti; + + if (after_bootmem) + return; + ti = &temp_mappings[i]; set_pmd(ti->pmd, __pmd(0)); ti->allocated = 0; } -static void __init phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) + +static void __devinit +phys_pmd_init(pmd_t *pmd, unsigned long address, unsigned long end) +{ + int i; + + printk("%s: pmd: 0x%p, address: 0x%lx end: 0x%lx\n", + __func__, pmd, address, end); + + for (i = 0; i < PTRS_PER_PMD; pmd++, i++, address += PMD_SIZE) { + unsigned long entry; + + if (address > end) { + for (; i < PTRS_PER_PMD; i++, pmd++) + set_pmd(pmd, __pmd(0)); + break; + } + entry = _PAGE_NX|_PAGE_PSE | _KERNPG_TABLE | _PAGE_GLOBAL | address; + entry &= __supported_pte_mask; + set_pmd(pmd, __pmd(entry)); + } +} + + +static void __devinit +phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end) +{ + pmd_t *pmd = pmd_offset(pud, (unsigned long)__va(address)); + + printk("%s: addr: 0x%lx end: 0x%lx pmd: 0x%p\n", + __func__, address, end, pmd); + + if (pmd_none(*pmd)) { + spin_lock(&init_mm.page_table_lock); + phys_pmd_init(pmd, address, end); + spin_unlock(&init_mm.page_table_lock); + __flush_tlb_all(); + } +} + + + +static void __devinit phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) { - long i, j; + long i = pud_index(address); - i = pud_index(address); pud = pud + i; + + if (after_bootmem && pud_val(*pud)) { + phys_pmd_update(pud, address, end); + return; + } + for (; i < PTRS_PER_PUD; pud++, i++) { int map; unsigned long paddr, pmd_phys; pmd_t *pmd; - paddr = address + i*PUD_SIZE; - if (paddr >= end) { - for (; i < PTRS_PER_PUD; i++, pud++) - set_pud(pud, __pud(0)); + paddr = (address & PGDIR_MASK) + i*PUD_SIZE; + if (paddr >= end) break; - } - if (!e820_mapped(paddr, paddr+PUD_SIZE, 0)) { + if (!after_bootmem && !e820_mapped(paddr, paddr+PUD_SIZE, 0)) { set_pud(pud, __pud(0)); continue; } pmd = alloc_low_page(&map, &pmd_phys); + if (after_bootmem) spin_lock(&init_mm.page_table_lock); set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE)); - for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) { - unsigned long pe; - - if (paddr >= end) { - for (; j < PTRS_PER_PMD; j++, pmd++) - set_pmd(pmd, __pmd(0)); - break; - } - pe = _PAGE_NX|_PAGE_PSE | _KERNPG_TABLE | _PAGE_GLOBAL | paddr; - pe &= __supported_pte_mask; - set_pmd(pmd, __pmd(pe)); - } + phys_pmd_init(pmd, paddr, end); + if (after_bootmem) spin_unlock(&init_mm.page_table_lock); unmap_low_page(map); } __flush_tlb(); @@ -267,12 +315,16 @@ static void __init find_early_table_spac table_start >>= PAGE_SHIFT; table_end = table_start; + + early_printk("kernel direct mapping tables upto %lx @ %lx-%lx\n", end, + table_start< end) next = end; phys_pud_init(pud, __pa(start), __pa(next)); - set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys)); + if (!after_bootmem) + set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys)); unmap_low_page(map); } - asm volatile("movq %%cr4,%0" : "=r" (mmu_cr4_features)); + if (!after_bootmem) + asm volatile("movq %%cr4,%0" : "=r" (mmu_cr4_features)); __flush_tlb_all(); - early_printk("kernel direct mapping tables upto %lx @ %lx-%lx\n", end, - table_start<node_zones + MAX_NR_ZONES - 2; + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + ret = __add_pages(zone, start_pfn, nr_pages, attr); + if (ret) + goto error; + + init_memory_mapping(start, (start + size - 1)); + + return ret; +error: + printk("%s: Problem encountered in __add_pages!\n", __func__); + return ret; +} +EXPORT_SYMBOL(add_memory); + +int remove_memory(u64 start, u64 size, unsigned long attr) +{ + struct zone *zone; + unsigned long start_pfn, end_pfn, nr_pages; + + printk("%s: start: 0x%llx size: 0x%llx attr: 0x%lx\n", + __func__, start, size, attr); + + start_pfn = start >> PAGE_SHIFT; + nr_pages = size >> PAGE_SHIFT; + /* end_pfn is the last *valid* pfn */ + end_pfn = start_pfn + nr_pages - 1; + + zone = page_zone(pfn_to_page(start_pfn)); + + printk("%s: memory will be removed from the %s zone\n", + __func__, zone->name); + printk("%s: start_pfn: 0x%lx nr_pages: 0x%lx end_pfn: 0x%lx\n", + __func__, start_pfn, nr_pages, end_pfn); + + if (zone != page_zone(pfn_to_page(end_pfn))) + goto overlap; + + printk("%s: just before remove pages\n", __func__); + + return __remove_pages(zone, start_pfn, nr_pages, attr); +overlap: + printk("%s: memory range overlaps multiple zones?\n", __func__); + return -ENOSYS; +} +EXPORT_SYMBOL(remove_memory); + +#endif + extern int swiotlb_force; static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, kcore_modules, diff -puN include/asm-x86_64/mman.h~L4-x86-64-memory-hotplug-no-sparse include/asm-x86_64/mman.h _