[RESEND PATCH v4 2/8] hugetlbfs: Use arch_get_mmap_* macros

Amanieu d'Antras
2021-05-18T09:08:03Z

hugetlb_get_unmapped_area should obey the same arch-specific constraints
as mmap when selecting an address.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Co-developed-by: Ryan Houdek <Houdek.Ryan@fex-emu.org>
Signed-off-by: Ryan Houdek <Houdek.Ryan@fex-emu.org>
---
fs/hugetlbfs/inode.c | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 701c82c36138..526ccb524329 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -191,6 +191,18 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
*/

#ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#ifndef arch_get_mmap_end
+#define arch_get_mmap_end(addr) (TASK_SIZE)
+#endif
+
+#ifndef arch_get_mmap_base
+#define arch_get_mmap_base(addr) (current->mm->mmap_base)
+#endif
+
+#ifndef arch_get_mmap_base_topdown
+#define arch_get_mmap_base_topdown(addr) (current->mm->mmap_base)
+#endif
+
static unsigned long
hugetlb_get_unmapped_area_bottomup(struct file *file, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags)
@@ -200,8 +212,8 @@ hugetlb_get_unmapped_area_bottomup(struct file *file, unsigned long addr,

info.flags = 0;
info.length = len;
- info.low_limit = current->mm->mmap_base;
- info.high_limit = TASK_SIZE;
+ info.low_limit = arch_get_mmap_base(addr);
+ info.high_limit = arch_get_mmap_end(addr);
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
return vm_unmapped_area(&info);
@@ -217,7 +229,7 @@ hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long addr,
info.flags = VM_UNMAPPED_AREA_TOPDOWN;
info.length = len;
info.low_limit = max(PAGE_SIZE, mmap_min_addr);
- info.high_limit = current->mm->mmap_base;
+ info.high_limit = arch_get_mmap_base_topdown(addr);
info.align_mask = PAGE_MASK & ~huge_page_mask(h);
info.align_offset = 0;
addr = vm_unmapped_area(&info);
@@ -231,8 +243,8 @@ hugetlb_get_unmapped_area_topdown(struct file *file, unsigned long addr,
if (unlikely(offset_in_page(addr))) {
VM_BUG_ON(addr != -ENOMEM);
info.flags = 0;
- info.low_limit = current->mm->mmap_base;
- info.high_limit = TASK_SIZE;
+ info.low_limit = arch_get_mmap_base(addr);
+ info.high_limit = arch_get_mmap_end(addr);
addr = vm_unmapped_area(&info);
}

--
2.31.1