diff options
| author | Janosch Frank <frankja@linux.ibm.com> | 2018-07-13 11:28:37 +0100 |
|---|---|---|
| committer | Janosch Frank <frankja@linux.ibm.com> | 2018-07-30 23:13:38 +0200 |
| commit | a9e00d8349c98e0973c8b0d671d69e838f7b5bcc (patch) | |
| tree | b6c9a4374f72c0f6ccea510dc8fc1f8c74d43d2d /arch/s390/mm/gmap.c | |
| parent | 7d735b9ae82d073e23ff7d2648e0aa8056049d16 (diff) | |
s390/mm: Add huge page gmap linking support
Let's allow huge pmd linking when enabled through the
KVM_CAP_S390_HPAGE_1M capability. Also we can now restrict gmap
invalidation and notification to the cases where the capability has
been activated and save some cycles when that's not the case.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Diffstat (limited to 'arch/s390/mm/gmap.c')
| -rw-r--r-- | arch/s390/mm/gmap.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/s390/mm/gmap.c b/arch/s390/mm/gmap.c index 736ed32a83c5..bb44990c8212 100644 --- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -2,8 +2,10 @@ /* * KVM guest address space mapping code * - * Copyright IBM Corp. 2007, 2016 + * Copyright IBM Corp. 2007, 2016, 2018 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> + * David Hildenbrand <david@redhat.com> + * Janosch Frank <frankja@linux.vnet.ibm.com> */ #include <linux/kernel.h> @@ -588,8 +590,8 @@ int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) return -EFAULT; pmd = pmd_offset(pud, vmaddr); VM_BUG_ON(pmd_none(*pmd)); - /* large pmds cannot yet be handled */ - if (pmd_large(*pmd)) + /* Are we allowed to use huge pages? */ + if (pmd_large(*pmd) && !gmap->mm->context.allow_gmap_hpage_1m) return -EFAULT; /* Link gmap segment table entry location to page table. */ rc = radix_tree_preload(GFP_KERNEL); @@ -1632,6 +1634,7 @@ struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, unsigned long limit; int rc; + BUG_ON(parent->mm->context.allow_gmap_hpage_1m); BUG_ON(gmap_is_shadow(parent)); spin_lock(&parent->shadow_lock); sg = gmap_find_shadow(parent, asce, edat_level); |