[PATCH 3/5] mm: Rename __thp_get_unmapped_area to mm_get_unmapped_area_aligned

Peter Xu
2025-06-13T13:41:23Z

This function is pretty handy for any type of VMA to provide a size-aligned
VMA address when mmap(). Rename the function and export it.

About the rename:

- Dropping "THP" because it doesn't really have much to do with THP
internally.

- The suffix "_aligned" imply it is a helper to generate aligned virtual
address based on what is specified (which can be not PMD_SIZE).

Cc: Zi Yan <ziy@nvidia.com>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
include/linux/huge_mm.h | 14 +++++++++++++-
mm/huge_memory.c | 6 ++++--
2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 2f190c90192d..706488d92bb6 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -339,7 +339,10 @@ unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr,
unsigned long thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags,
vm_flags_t vm_flags);
-
+unsigned long mm_get_unmapped_area_aligned(struct file *filp,
+ unsigned long addr, unsigned long len,
+ loff_t off, unsigned long flags, unsigned long size,
+ vm_flags_t vm_flags);
bool can_split_folio(struct folio *folio, int caller_pins, int *pextra_pins);
int split_huge_page_to_list_to_order(struct page *page, struct list_head *list,
unsigned int new_order);
@@ -543,6 +546,15 @@ thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr,
return 0;
}

+static inline unsigned long
+mm_get_unmapped_area_aligned(struct file *filp,
+ unsigned long addr, unsigned long len,
+ loff_t off, unsigned long flags, unsigned long size,
+ vm_flags_t vm_flags)
+{
+ return 0;
+}
+
static inline bool
can_split_folio(struct folio *folio, int caller_pins, int *pextra_pins)
{
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 4734de1dc0ae..52f13a70562f 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1088,7 +1088,7 @@ static inline bool is_transparent_hugepage(const struct folio *folio)
folio_test_large_rmappable(folio);
}

-static unsigned long __thp_get_unmapped_area(struct file *filp,
+unsigned long mm_get_unmapped_area_aligned(struct file *filp,
unsigned long addr, unsigned long len,
loff_t off, unsigned long flags, unsigned long size,
vm_flags_t vm_flags)
@@ -1132,6 +1132,7 @@ static unsigned long __thp_get_unmapped_area(struct file *filp,
ret += off_sub;
return ret;
}
+EXPORT_SYMBOL_GPL(mm_get_unmapped_area_aligned);

unsigned long thp_get_unmapped_area_vmflags(struct file *filp, unsigned long addr,
unsigned long len, unsigned long pgoff, unsigned long flags,
@@ -1140,7 +1141,8 @@ unsigned long thp_get_unmapped_area_vmflags(struct file *filp, unsigned long add
unsigned long ret;
loff_t off = (loff_t)pgoff << PAGE_SHIFT;

- ret = __thp_get_unmapped_area(filp, addr, len, off, flags, PMD_SIZE, vm_flags);
+ ret = mm_get_unmapped_area_aligned(filp, addr, len, off, flags,
+ PMD_SIZE, vm_flags);
if (ret)
return ret;

--
2.49.0