[RFC,v2,7/8] shmem: add high order page support

Message ID 20230526075552.363524-8-mcgrof@kernel.org
State New
Headers
Series add support for blocksize > PAGE_SIZE |

Commit Message

Luis Chamberlain May 26, 2023, 7:55 a.m. UTC
  To support high order block sizes we want to support a high order
folios so to treat the larger block atomically. Add support for this
for tmpfs mounts.

Right now this produces no functional changes since we only allow one
single block size, matching the PAGE_SIZE and so the order is always 0.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 mm/shmem.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
  

Patch

diff --git a/mm/shmem.c b/mm/shmem.c
index d347a5ba49f1..080864949fe5 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1623,9 +1623,15 @@  static struct folio *shmem_alloc_folio(gfp_t gfp,
 {
 	struct vm_area_struct pvma;
 	struct folio *folio;
+	struct inode *inode = &info->vfs_inode;
+	struct super_block *i_sb = inode->i_sb;
+	int order = 0;
+
+	if (!(i_sb->s_flags & SB_KERNMOUNT))
+		order = i_sb->s_blocksize_bits - PAGE_SHIFT;
 
 	shmem_pseudo_vma_init(&pvma, info, index);
-	folio = vma_alloc_folio(gfp, 0, &pvma, 0, false);
+	folio = vma_alloc_folio(gfp, order, &pvma, 0, false);
 	shmem_pseudo_vma_destroy(&pvma);
 
 	return folio;