arch/s390: teach arch_get_unmapped_area{_topdown} to handle hugetlb mappings

We want to stop special casing hugetlb mappings and make them go through
generic channels, so teach arch_get_unmapped_area{_topdown} to handle
those.

s390 specific hugetlb function does not set info.align_offset, so do the
same here for compatibility.

Link: https://lkml.kernel.org/r/20241007075037.267650-3-osalvador@suse.de
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
index 96efa061ce01ba9ed650ac7a45e956b24527da8d..33f3504be90b593f3f23bc2746a4192fe2653fe1 100644 (file)
--- a/arch/s390/mm/mmap.c
+++ b/arch/s390/mm/mmap.c
@@ -17,6 +17,7 @@
 #include <linux/random.h>
 #include <linux/compat.h>
 #include <linux/security.h>
+#include <linux/hugetlb.h>
 #include <asm/elf.h>
 
 static unsigned long stack_maxrandom_size(void)
@@ -73,6 +74,8 @@ static inline unsigned long mmap_base(unsigned long rnd,
 
 static int get_align_mask(struct file *filp, unsigned long flags)
 {
+       if (filp && is_file_hugepages(filp))
+               return huge_page_mask_align(filp);
        if (!(current->flags & PF_RANDOMIZE))
                return 0;
        if (filp || (flags & MAP_SHARED))
@@ -106,7 +109,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
        info.low_limit = mm->mmap_base;
        info.high_limit = TASK_SIZE;
        info.align_mask = get_align_mask(filp, flags);
-       info.align_offset = pgoff << PAGE_SHIFT;
+       if (!(filp && is_file_hugepages(filp)))
+               info.align_offset = pgoff << PAGE_SHIFT;
        addr = vm_unmapped_area(&info);
        if (offset_in_page(addr))
                return addr;
@@ -144,7 +148,8 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp, unsigned long ad
        info.low_limit = PAGE_SIZE;
        info.high_limit = mm->mmap_base;
        info.align_mask = get_align_mask(filp, flags);
-       info.align_offset = pgoff << PAGE_SHIFT;
+       if (!(filp && is_file_hugepages(filp)))
+               info.align_offset = pgoff << PAGE_SHIFT;
        addr = vm_unmapped_area(&info);
 
        /*