[PATCH v4 04/36] mm: Introduce thp_size

Matthew Wilcox
2020-05-15T13:17:12Z

This is like page_size(), but compiles down to just PAGE_SIZE if THP
are disabled. Convert the users of hpage_nr_pages() which would prefer
this interface.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
drivers/nvdimm/btt.c | 4 +---
drivers/nvdimm/pmem.c | 6 ++----
include/linux/huge_mm.h | 7 +++++++
mm/internal.h | 2 +-
mm/page_io.c | 2 +-
mm/page_vma_mapped.c | 4 ++--
6 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 3b09419218d6..78e8d972d45a 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -1488,10 +1488,8 @@ static int btt_rw_page(struct block_device *bdev, sector_t sector,
{
struct btt *btt = bdev->bd_disk->private_data;
int rc;
- unsigned int len;

- len = hpage_nr_pages(page) * PAGE_SIZE;
- rc = btt_do_bvec(btt, NULL, page, len, 0, op, sector);
+ rc = btt_do_bvec(btt, NULL, page, thp_size(page), 0, op, sector);
if (rc == 0)
page_endio(page, op_is_write(op), 0);

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 2df6994acf83..d511504d07af 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -235,11 +235,9 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,
blk_status_t rc;

if (op_is_write(op))
- rc = pmem_do_write(pmem, page, 0, sector,
- hpage_nr_pages(page) * PAGE_SIZE);
+ rc = pmem_do_write(pmem, page, 0, sector, thp_size(page));
else
- rc = pmem_do_read(pmem, page, 0, sector,
- hpage_nr_pages(page) * PAGE_SIZE);
+ rc = pmem_do_read(pmem, page, 0, sector, thp_size(page));
/*
* The ->rw_page interface is subtle and tricky. The core
* retries on any error, so we can only invoke page_endio() in
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 6bec4b5b61e1..e944f9757349 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -271,6 +271,11 @@ static inline int hpage_nr_pages(struct page *page)
return compound_nr(page);
}

+static inline unsigned long thp_size(struct page *page)
+{
+ return page_size(page);
+}
+
struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
pmd_t *pmd, int flags, struct dev_pagemap **pgmap);
struct page *follow_devmap_pud(struct vm_area_struct *vma, unsigned long addr,
@@ -329,6 +334,8 @@ static inline int hpage_nr_pages(struct page *page)
return 1;
}

+#define thp_size(x) PAGE_SIZE
+
static inline bool __transparent_hugepage_enabled(struct vm_area_struct *vma)
{
return false;
diff --git a/mm/internal.h b/mm/internal.h
index f762a34b0c57..5efb13d5c226 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -386,7 +386,7 @@ vma_address(struct page *page, struct vm_area_struct *vma)
unsigned long start, end;

start = __vma_address(page, vma);
- end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1);
+ end = start + thp_size(page) - PAGE_SIZE;

/* page should be within @vma mapping range */
VM_BUG_ON_VMA(end < vma->vm_start || start >= vma->vm_end, vma);
diff --git a/mm/page_io.c b/mm/page_io.c
index 76965be1d40e..dd935129e3cb 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -41,7 +41,7 @@ static struct bio *get_swap_bio(gfp_t gfp_flags,
bio->bi_iter.bi_sector <<= PAGE_SHIFT - 9;
bio->bi_end_io = end_io;

- bio_add_page(bio, page, PAGE_SIZE * hpage_nr_pages(page), 0);
+ bio_add_page(bio, page, thp_size(page), 0);
}
return bio;
}
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 719c35246cfa..e65629c056e8 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -227,7 +227,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
if (pvmw->address >= pvmw->vma->vm_end ||
pvmw->address >=
__vma_address(pvmw->page, pvmw->vma) +
- hpage_nr_pages(pvmw->page) * PAGE_SIZE)
+ thp_size(pvmw->page))
return not_found(pvmw);
/* Did we cross page table boundary? */
if (pvmw->address % PMD_SIZE == 0) {
@@ -268,7 +268,7 @@ int page_mapped_in_vma(struct page *page, struct vm_area_struct *vma)
unsigned long start, end;

start = __vma_address(page, vma);
- end = start + PAGE_SIZE * (hpage_nr_pages(page) - 1);
+ end = start + thp_size(page) - PAGE_SIZE;

if (unlikely(end < vma->vm_start || start >= vma->vm_end))
return 0;
--
2.26.2