do_set_pte_range() allows to setup page table entries for a
specific range. It calls folio_add_file_rmap_range() to take
advantage of batched rmap update for large folio.
Signed-off-by: Yin Fengwei <fengwei.yin@xxxxxxxxx>
---
include/linux/mm.h | 3 +++
mm/filemap.c | 1 -
mm/memory.c | 66 ++++++++++++++++++++++++++++++++--------------
3 files changed, 49 insertions(+), 21 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index d6f8f41514cc..93192f04b276 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1162,6 +1162,9 @@ static inline pte_t maybe_mkwrite(pte_t pte, struct vm_area_struct *vma)
vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page);
void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr);
+void do_set_pte_range(struct vm_fault *vmf, struct folio *folio,
+ unsigned long addr, pte_t *pte,
+ unsigned long start, unsigned int nr);
vm_fault_t finish_fault(struct vm_fault *vmf);
vm_fault_t finish_mkwrite_fault(struct vm_fault *vmf);
diff --git a/mm/filemap.c b/mm/filemap.c
index 1c37376fc8d5..6f110b9e5d27 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3376,7 +3376,6 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf,
ref_count++;
do_set_pte(vmf, page, addr);
- update_mmu_cache(vma, addr, vmf->pte);
} while (vmf->pte++, page++, addr += PAGE_SIZE, ++count < nr_pages);
/* Restore the vmf->pte */
diff --git a/mm/memory.c b/mm/memory.c
index 7a04a1130ec1..51f8bd91d9f0 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4257,36 +4257,65 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
}
#endif
-void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr)
+void do_set_pte_range(struct vm_fault *vmf, struct folio *folio,
+ unsigned long addr, pte_t *pte,
+ unsigned long start, unsigned int nr)
{
struct vm_area_struct *vma = vmf->vma;
bool uffd_wp = pte_marker_uffd_wp(vmf->orig_pte);
bool write = vmf->flags & FAULT_FLAG_WRITE;
+ bool cow = write && !(vma->vm_flags & VM_SHARED);
bool prefault = vmf->address != addr;
+ struct page *page = folio_page(folio, start);
pte_t entry;
- flush_icache_page(vma, page);
- entry = mk_pte(page, vma->vm_page_prot);
+ if (!cow) {
+ folio_add_file_rmap_range(folio, start, nr, vma, false);
+ add_mm_counter(vma->vm_mm, mm_counter_file(page), nr);
+ } else {
+ /*
+ * rmap code is not ready to handle COW with anonymous
+ * large folio yet. Capture and warn if large folio
+ * is given.
+ */
+ VM_WARN_ON_FOLIO(folio_test_large(folio), folio);
+ }
- if (prefault && arch_wants_old_prefaulted_pte())
- entry = pte_mkold(entry);
- else
- entry = pte_sw_mkyoung(entry);
+ do {
+ flush_icache_page(vma, page);
+ entry = mk_pte(page, vma->vm_page_prot);
- if (write)
- entry = maybe_mkwrite(pte_mkdirty(entry), vma);
- if (unlikely(uffd_wp))
- entry = pte_mkuffd_wp(entry);
- /* copy-on-write page */
- if (write && !(vma->vm_flags & VM_SHARED)) {
+ if (prefault && arch_wants_old_prefaulted_pte())
+ entry = pte_mkold(entry);
+ else
+ entry = pte_sw_mkyoung(entry);
+
+ if (write)
+ entry = maybe_mkwrite(pte_mkdirty(entry), vma);
+ if (unlikely(uffd_wp))
+ entry = pte_mkuffd_wp(entry);
+ set_pte_at(vma->vm_mm, addr, pte, entry);
+
+ /* no need to invalidate: a not-present page won't be cached */
+ update_mmu_cache(vma, addr, pte);
+ } while (pte++, page++, addr += PAGE_SIZE, --nr > 0);
+}
+
+void do_set_pte(struct vm_fault *vmf, struct page *page, unsigned long addr)
+{
+ struct folio *folio = page_folio(page);
+ struct vm_area_struct *vma = vmf->vma;
+ bool cow = (vmf->flags & FAULT_FLAG_WRITE) &&
+ !(vma->vm_flags & VM_SHARED);
+
+ if (cow) {
inc_mm_counter(vma->vm_mm, MM_ANONPAGES);
page_add_new_anon_rmap(page, vma, addr);
lru_cache_add_inactive_or_unevictable(page, vma);
- } else {
- inc_mm_counter(vma->vm_mm, mm_counter_file(page));
- page_add_file_rmap(page, vma, false);
}
- set_pte_at(vma->vm_mm, addr, vmf->pte, entry);
+
+ do_set_pte_range(vmf, folio, addr, vmf->pte,
+ folio_page_idx(folio, page), 1);
}
static bool vmf_pte_changed(struct vm_fault *vmf)
@@ -4361,9 +4390,6 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
if (likely(!vmf_pte_changed(vmf))) {
do_set_pte(vmf, page, vmf->address);
- /* no need to invalidate: a not-present page won't be cached */
- update_mmu_cache(vma, vmf->address, vmf->pte);
-
ret = 0;
} else {
update_mmu_tlb(vma, vmf->address, vmf->pte);
--
2.30.2
