[PATCH v8 06/10] mm/vmalloc: extract vmap_set_ptes() to consolidate PTE mapping logic

[Wen Jiang <jiangwenxiaomi@gmail.com>]

From: Wen Jiang <jiangwen6@xiaomi.com>

Extract the common PTE mapping logic from vmap_pte_range() into a
shared helper vmap_set_ptes(). This handles both CONT_PTE and regular
PTE mappings in a single function, preparing for the next patch which
will extend vmap_pages_pte_range() to also use this helper.

No functional change.

Signed-off-by: Wen Jiang <jiangwen6@xiaomi.com>
Tested-by: Xueyuan Chen <xueyuan.chen21@gmail.com>
Tested-by: Leo Yan <leo.yan@arm.com>
---
 mm/vmalloc.c | 36 +++++++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 9 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 025b3a848d564..a0508bdb7d36f 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -90,6 +90,29 @@ struct vfree_deferred {
 static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
 
 /*** Page table manipulation functions ***/
+
+/*
+ * Try contiguous mappings at the PTE level for arches which support them, and if
+ * requested by the caller. Fall back to PAGE_SIZE mappings otherwise.
+ *
+ * Return: mapping size.
+ */
+static __always_inline unsigned long vmap_set_ptes(pte_t *ptep,
+		unsigned long addr, unsigned long end, u64 pfn,
+		pgprot_t prot, unsigned int max_page_shift)
+{
+	unsigned long size;
+
+	size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
+	if (size != PAGE_SIZE) {
+		pte_set_huge(ptep, addr, PFN_PHYS(pfn), prot, size);
+		return size;
+	}
+
+	set_pte_at(&init_mm, addr, ptep, pfn_pte(pfn, prot));
+	return PAGE_SIZE;
+}
+
 static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			phys_addr_t phys_addr, pgprot_t prot,
 			unsigned int max_page_shift, pgtbl_mod_mask *mask)
@@ -98,6 +121,7 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	u64 pfn;
 	struct page *page;
 	unsigned long size;
+	unsigned int steps;
 
 	if (WARN_ON_ONCE(!PAGE_ALIGNED(end - addr)))
 		return -EINVAL;
@@ -118,15 +142,9 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 			BUG();
 		}
 
-		size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
-		if (size != PAGE_SIZE) {
-			pte_set_huge(pte, addr, PFN_PHYS(pfn), prot, size);
-			pfn += PFN_DOWN(size);
-			continue;
-		}
-		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
-		pfn++;
-	} while (pte += PFN_DOWN(size), addr += size, addr != end);
+		size = vmap_set_ptes(pte, addr, end, pfn, prot, max_page_shift);
+		steps = PFN_DOWN(size);
+	} while (pte += steps, pfn += steps, addr += size, addr != end);
 
 	lazy_mmu_mode_disable();
 	*mask |= PGTBL_PTE_MODIFIED;
-- 
2.34.1