Commit 3072e413 authored by Michal Hocko's avatar Michal Hocko Committed by Linus Torvalds

mm/memory_hotplug: introduce add_pages

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.comSigned-off-by: default avatarMichal Hocko <mhocko@suse.com>
Signed-off-by: default avatarJérôme Glisse <jglisse@redhat.com>
Acked-by: default avatarBalbir Singh <bsingharora@gmail.com>
Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Evgeny Baskakov <ebaskakov@nvidia.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mark Hairgrove <mhairgrove@nvidia.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Sherry Cheung <SCheung@nvidia.com>
Cc: Subhash Gutti <sgutti@nvidia.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Bob Liu <liubo95@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 74eee180
......@@ -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)
......
......@@ -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
......
......@@ -133,6 +133,17 @@ extern int __remove_pages(struct zone *zone, unsigned long start_pfn,
extern int __add_pages(int nid, unsigned long start_pfn,
unsigned long nr_pages, bool want_memblock);
#ifndef CONFIG_ARCH_HAS_ADD_PAGES
static inline int add_pages(int nid, unsigned long start_pfn,
unsigned long nr_pages, bool want_memblock)
{
return __add_pages(nid, start_pfn, nr_pages, want_memblock);
}
#else /* ARCH_HAS_ADD_PAGES */
int add_pages(int nid, unsigned long start_pfn,
unsigned long nr_pages, bool want_memblock);
#endif /* ARCH_HAS_ADD_PAGES */
#ifdef CONFIG_NUMA
extern int memory_add_physaddr_to_nid(u64 start);
#else
......
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