[3/7] dax: Simplify arguments of dax_insert_mapping()

Commit Message

Jan Kara July 27, 2017, 1:12 p.m. UTC

dax_insert_mapping() has lots of arguments and a lot of them is actuall
duplicated by passing vm_fault structure as well. Change the function to
take the same arguments as dax_pmd_insert_mapping().

Signed-off-by: Jan Kara <[e-mail]>
---
 fs/dax.c | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

Comments

Ross Zwisler July 27, 2017, 10:09 p.m. UTC | #1

On Thu, Jul 27, 2017 at 03:12:41PM +0200, Jan Kara wrote:
> dax_insert_mapping() has lots of arguments and a lot of them is actuall
								  actually
> duplicated by passing vm_fault structure as well. Change the function to
> take the same arguments as dax_pmd_insert_mapping().

Yay, this is much better!

> Signed-off-by: Jan Kara <[e-mail]>

Reviewed-by: Ross Zwisler <[e-mail]>

Christoph Hellwig Aug. 1, 2017, 10:54 a.m. UTC | #2

On Thu, Jul 27, 2017 at 03:12:41PM +0200, Jan Kara wrote:
> dax_insert_mapping() has lots of arguments and a lot of them is actuall
> duplicated by passing vm_fault structure as well. Change the function to
> take the same arguments as dax_pmd_insert_mapping().

Some of this is probably for historic reasons, when I did the initial
pass at iomap based DAX dax_insert_mapping still had to be usable for
the non-DAX case.

Either way this looks like a great cleanup:

Reviewed-by: Christoph Hellwig <[e-mail]>

Patch

diff --git a/fs/dax.c b/fs/dax.c
index 44d9cce4399b..0673efd72f53 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -814,23 +814,30 @@  int dax_writeback_mapping_range(struct address_space *mapping,
 }
 EXPORT_SYMBOL_GPL(dax_writeback_mapping_range);
 
-static int dax_insert_mapping(struct address_space *mapping,
-		struct block_device *bdev, struct dax_device *dax_dev,
-		sector_t sector, size_t size, void *entry,
-		struct vm_area_struct *vma, struct vm_fault *vmf)
+static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
+{
+	return iomap->blkno + (((pos & PAGE_MASK) - iomap->offset) >> 9);
+}
+
+static int dax_insert_mapping(struct vm_fault *vmf, struct iomap *iomap,
+			      loff_t pos, void *entry)
 {
+	const sector_t sector = dax_iomap_sector(iomap, pos);
+	struct vm_area_struct *vma = vmf->vma;
+	struct address_space *mapping = vma->vm_file->f_mapping;
 	unsigned long vaddr = vmf->address;
 	void *ret, *kaddr;
 	pgoff_t pgoff;
 	int id, rc;
 	pfn_t pfn;
 
-	rc = bdev_dax_pgoff(bdev, sector, size, &pgoff);
+	rc = bdev_dax_pgoff(iomap->bdev, sector, PAGE_SIZE, &pgoff);
 	if (rc)
 		return rc;
 
 	id = dax_read_lock();
-	rc = dax_direct_access(dax_dev, pgoff, PHYS_PFN(size), &kaddr, &pfn);
+	rc = dax_direct_access(iomap->dax_dev, pgoff, PHYS_PFN(PAGE_SIZE),
+			       &kaddr, &pfn);
 	if (rc < 0) {
 		dax_read_unlock(id);
 		return rc;
@@ -930,11 +937,6 @@  int __dax_zero_page_range(struct block_device *bdev,
 }
 EXPORT_SYMBOL_GPL(__dax_zero_page_range);
 
-static sector_t dax_iomap_sector(struct iomap *iomap, loff_t pos)
-{
-	return iomap->blkno + (((pos & PAGE_MASK) - iomap->offset) >> 9);
-}
-
 static loff_t
 dax_iomap_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
 		struct iomap *iomap)
@@ -1076,7 +1078,6 @@  static int dax_iomap_pte_fault(struct vm_fault *vmf, bool sync,
 	struct inode *inode = mapping->host;
 	unsigned long vaddr = vmf->address;
 	loff_t pos = (loff_t)vmf->pgoff << PAGE_SHIFT;
-	sector_t sector;
 	struct iomap iomap = { 0 };
 	unsigned flags = IOMAP_FAULT;
 	int error, major = 0;
@@ -1129,9 +1130,9 @@  static int dax_iomap_pte_fault(struct vm_fault *vmf, bool sync,
 		goto error_finish_iomap;
 	}
 
-	sector = dax_iomap_sector(&iomap, pos);
-
 	if (vmf->cow_page) {
+		sector_t sector = dax_iomap_sector(&iomap, pos);
+
 		switch (iomap.type) {
 		case IOMAP_HOLE:
 		case IOMAP_UNWRITTEN:
@@ -1164,8 +1165,7 @@  static int dax_iomap_pte_fault(struct vm_fault *vmf, bool sync,
 			count_memcg_event_mm(vmf->vma->vm_mm, PGMAJFAULT);
 			major = VM_FAULT_MAJOR;
 		}
-		error = dax_insert_mapping(mapping, iomap.bdev, iomap.dax_dev,
-				sector, PAGE_SIZE, entry, vmf->vma, vmf);
+		error = dax_insert_mapping(vmf, &iomap, pos, entry);
 		/* -EBUSY is fine, somebody else faulted on the same PTE */
 		if (error == -EBUSY)
 			error = 0;