1 files changed, 24 insertions, 14 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 41a0fbddc96b..a88093213674 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -527,13 +527,13 @@ void prep_transhuge_page(struct page *page)
 	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
 }
 
-static unsigned long __thp_get_unmapped_area(struct file *filp, unsigned long len,
+static unsigned long __thp_get_unmapped_area(struct file *filp,
+		unsigned long addr, unsigned long len,
 		loff_t off, unsigned long flags, unsigned long size)
 {
-	unsigned long addr;
 	loff_t off_end = off + len;
 	loff_t off_align = round_up(off, size);
-	unsigned long len_pad;
+	unsigned long len_pad, ret;
 
 	if (off_end <= off_align || (off_end - off_align) < size)
 		return 0;
@@ -542,30 +542,40 @@ static unsigned long __thp_get_unmapped_area(struct file *filp, unsigned long le
 	if (len_pad < len || (off + len_pad) < off)
 		return 0;
 
-	addr = current->mm->get_unmapped_area(filp, 0, len_pad,
+	ret = current->mm->get_unmapped_area(filp, addr, len_pad,
 					      off >> PAGE_SHIFT, flags);
-	if (IS_ERR_VALUE(addr))
+
+	/*
+	 * The failure might be due to length padding. The caller will retry
+	 * without the padding.
+	 */
+	if (IS_ERR_VALUE(ret))
 		return 0;
 
-	addr += (off - addr) & (size - 1);
-	return addr;
+	/*
+	 * Do not try to align to THP boundary if allocation at the address
+	 * hint succeeds.
+	 */
+	if (ret == addr)
+		return addr;
+
+	ret += (off - ret) & (size - 1);
+	return ret;
 }
 
 unsigned long thp_get_unmapped_area(struct file *filp, unsigned long addr,
 		unsigned long len, unsigned long pgoff, unsigned long flags)
 {
+	unsigned long ret;
 	loff_t off = (loff_t)pgoff << PAGE_SHIFT;
 
-	if (addr)
-		goto out;
 	if (!IS_DAX(filp->f_mapping->host) || !IS_ENABLED(CONFIG_FS_DAX_PMD))
 		goto out;
 
-	addr = __thp_get_unmapped_area(filp, len, off, flags, PMD_SIZE);
-	if (addr)
-		return addr;
-
- out:
+	ret = __thp_get_unmapped_area(filp, addr, len, off, flags, PMD_SIZE);
+	if (ret)
+		return ret;
+out:
 	return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
 }
 EXPORT_SYMBOL_GPL(thp_get_unmapped_area);