[for,4.19-stable,v2,13/24] s390x/mm: implement arch_remove_memory()

Commit Message

David Hildenbrand Jan. 21, 2020, 6:01 p.m. UTC

commit 18c86506c80f6b6b5e67d95bf0d6f7e665de5239 upstream.

Will come in handy when wanting to handle errors after
arch_add_memory().

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: David Hildenbrand <[e-mail]>
Cc: Heiko Carstens <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: Vasily Gorbik <[e-mail]>
Cc: Oscar Salvador <[e-mail]>
Cc: Alex Deucher <[e-mail]>
Cc: Andrew Banman <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Anshuman Khandual <[e-mail]>
Cc: Ard Biesheuvel <[e-mail]>
Cc: Arun KS <[e-mail]>
Cc: Baoquan He <[e-mail]>
Cc: Benjamin Herrenschmidt <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Catalin Marinas <[e-mail]>
Cc: Chintan Pandya <[e-mail]>
Cc: Christophe Leroy <[e-mail]>
Cc: Chris Wilson <[e-mail]>
Cc: Dan Williams <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: Fenghua Yu <[e-mail]>
Cc: Greg Kroah-Hartman <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jonathan Cameron <[e-mail]>
Cc: Joonsoo Kim <[e-mail]>
Cc: Jun Yao <[e-mail]>
Cc: "Kirill A. Shutemov" <[e-mail]>
Cc: Logan Gunthorpe <[e-mail]>
Cc: Mark Brown <[e-mail]>
Cc: Mark Rutland <[e-mail]>
Cc: Masahiro Yamada <[e-mail]>
Cc: Mathieu Malaterre <[e-mail]>
Cc: Michael Ellerman <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: "[e-mail]" <[e-mail]>
Cc: Nicholas Piggin <[e-mail]>
Cc: Oscar Salvador <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Pavel Tatashin <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Qian Cai <[e-mail]>
Cc: "Rafael J. Wysocki" <[e-mail]>
Cc: Rich Felker <[e-mail]>
Cc: Rob Herring <[e-mail]>
Cc: Robin Murphy <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Tony Luck <[e-mail]>
Cc: Wei Yang <[e-mail]>
Cc: Will Deacon <[e-mail]>
Cc: Yoshinori Sato <[e-mail]>
Cc: Yu Zhao <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>
Signed-off-by: David Hildenbrand <[e-mail]>
---
 arch/s390/mm/init.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

Patch

diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 0da486d914e4..fc761001fa94 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -243,12 +243,13 @@  int arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
 void arch_remove_memory(int nid, u64 start, u64 size,
 			struct vmem_altmap *altmap)
 {
-	/*
-	 * There is no hardware or firmware interface which could trigger a
-	 * hot memory remove on s390. So there is nothing that needs to be
-	 * implemented.
-	 */
-	BUG();
+	unsigned long start_pfn = start >> PAGE_SHIFT;
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	struct zone *zone;
+
+	zone = page_zone(pfn_to_page(start_pfn));
+	__remove_pages(zone, start_pfn, nr_pages, altmap);
+	vmem_remove_mapping(start, size);
 }
 #endif
 #endif /* CONFIG_MEMORY_HOTPLUG */