From 3072e413e305e353cd4654f8a57d953b66e85bf3 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Fri, 8 Sep 2017 16:11:39 -0700 Subject: mm/memory_hotplug: introduce add_pages MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There are new users of memory hotplug emerging. Some of them require different subset of arch_add_memory. There are some which only require allocation of struct pages without mapping those pages to the kernel address space. We currently have __add_pages for that purpose. But this is rather lowlevel and not very suitable for the code outside of the memory hotplug. E.g. x86_64 wants to update max_pfn which should be done by the caller. Introduce add_pages() which should care about those details if they are needed. Each architecture should define its implementation and select CONFIG_ARCH_HAS_ADD_PAGES. All others use the currently existing __add_pages. Link: http://lkml.kernel.org/r/20170817000548.32038-7-jglisse@redhat.com Signed-off-by: Michal Hocko Signed-off-by: Jérôme Glisse Acked-by: Balbir Singh Cc: Aneesh Kumar Cc: Benjamin Herrenschmidt Cc: Dan Williams Cc: David Nellans Cc: Evgeny Baskakov Cc: Johannes Weiner Cc: John Hubbard Cc: Kirill A. Shutemov Cc: Mark Hairgrove Cc: Paul E. McKenney Cc: Ross Zwisler Cc: Sherry Cheung Cc: Subhash Gutti Cc: Vladimir Davydov Cc: Bob Liu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/Kconfig | 4 ++++ arch/x86/mm/init_64.c | 22 +++++++++++++++------- 2 files changed, 19 insertions(+), 7 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 07d9b6c75328..a3e6e6136a47 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2323,6 +2323,10 @@ source "kernel/livepatch/Kconfig" endmenu +config ARCH_HAS_ADD_PAGES + def_bool y + depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG + config ARCH_ENABLE_MEMORY_HOTPLUG def_bool y depends on X86_64 || (X86_32 && HIGHMEM) diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 136422d7d539..048fbe8fc274 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -761,7 +761,7 @@ void __init paging_init(void) * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need * updating. */ -static void update_end_of_memory_vars(u64 start, u64 size) +static void update_end_of_memory_vars(u64 start, u64 size) { unsigned long end_pfn = PFN_UP(start + size); @@ -772,22 +772,30 @@ static void update_end_of_memory_vars(u64 start, u64 size) } } -int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock) +int add_pages(int nid, unsigned long start_pfn, + unsigned long nr_pages, bool want_memblock) { - unsigned long start_pfn = start >> PAGE_SHIFT; - unsigned long nr_pages = size >> PAGE_SHIFT; int ret; - init_memory_mapping(start, start + size); - ret = __add_pages(nid, start_pfn, nr_pages, want_memblock); WARN_ON_ONCE(ret); /* update max_pfn, max_low_pfn and high_memory */ - update_end_of_memory_vars(start, size); + update_end_of_memory_vars(start_pfn << PAGE_SHIFT, + nr_pages << PAGE_SHIFT); return ret; } + +int arch_add_memory(int nid, u64 start, u64 size, bool want_memblock) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + + init_memory_mapping(start, start + size); + + return add_pages(nid, start_pfn, nr_pages, want_memblock); +} EXPORT_SYMBOL_GPL(arch_add_memory); #define PAGE_INUSE 0xFD -- cgit v1.2.3