For synchronous page fault dax_iomap_fault() will need to return PFN
which will then need to inserted into page tables after fsync()
completes. Add necessary parameter to dax_iomap_fault().
Signed-off-by: Jan Kara <[email protected]>
---
fs/dax.c | 13 +++++++------
fs/ext2/file.c | 2 +-
fs/ext4/file.c | 2 +-
fs/xfs/xfs_file.c | 8 ++++----
include/linux/dax.h | 2 +-
5 files changed, 14 insertions(+), 13 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 85ea49bbbdbf..bc040e654cc9 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1069,7 +1069,7 @@ static int dax_fault_return(int error)
}
static int dax_iomap_pte_fault(struct vm_fault *vmf,
- const struct iomap_ops *ops)
+ const struct iomap_ops *ops, pfn_t *pfnp)
{
struct vm_area_struct *vma = vmf->vma;
struct address_space *mapping = vma->vm_file->f_mapping;
@@ -1270,7 +1270,7 @@ static int dax_pmd_load_hole(struct vm_fault *vmf, struct iomap *iomap,
}
static int dax_iomap_pmd_fault(struct vm_fault *vmf,
- const struct iomap_ops *ops)
+ const struct iomap_ops *ops, pfn_t *pfnp)
{
struct vm_area_struct *vma = vmf->vma;
struct address_space *mapping = vma->vm_file->f_mapping;
@@ -1405,7 +1405,7 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
}
#else
static int dax_iomap_pmd_fault(struct vm_fault *vmf,
- const struct iomap_ops *ops)
+ const struct iomap_ops *ops, pfn_t *pfnp)
{
return VM_FAULT_FALLBACK;
}
@@ -1416,6 +1416,7 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
* @vmf: The description of the fault
* @pe_size: Size of the page to fault in
* @ops: Iomap ops passed from the file system
+ * @pfnp: PFN to insert for synchronous faults if fsync is required
*
* When a page fault occurs, filesystems may call this helper in
* their fault handler for DAX files. dax_iomap_fault() assumes the caller
@@ -1423,13 +1424,13 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
* successfully.
*/
int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
- const struct iomap_ops *ops)
+ const struct iomap_ops *ops, pfn_t *pfnp)
{
switch (pe_size) {
case PE_SIZE_PTE:
- return dax_iomap_pte_fault(vmf, ops);
+ return dax_iomap_pte_fault(vmf, ops, pfnp);
case PE_SIZE_PMD:
- return dax_iomap_pmd_fault(vmf, ops);
+ return dax_iomap_pmd_fault(vmf, ops, pfnp);
default:
return VM_FAULT_FALLBACK;
}
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index ff3a3636a5ca..689f17b5f444 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -99,7 +99,7 @@ static int ext2_dax_fault(struct vm_fault *vmf)
}
down_read(&ei->dax_sem);
- ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &ext2_iomap_ops);
+ ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &ext2_iomap_ops, NULL);
up_read(&ei->dax_sem);
if (vmf->flags & FAULT_FLAG_WRITE)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 9dda70edba74..f84bb29e941e 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -291,7 +291,7 @@ static int ext4_dax_huge_fault(struct vm_fault *vmf,
down_read(&EXT4_I(inode)->i_mmap_sem);
}
if (!IS_ERR(handle))
- result = dax_iomap_fault(vmf, pe_size, &ext4_iomap_ops);
+ result = dax_iomap_fault(vmf, pe_size, &ext4_iomap_ops, NULL);
else
result = VM_FAULT_SIGBUS;
if (write) {
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 62db8ffa83b9..c17ca982272c 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1032,7 +1032,7 @@ xfs_filemap_page_mkwrite(
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
if (IS_DAX(inode)) {
- ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
+ ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops, NULL);
} else {
ret = iomap_page_mkwrite(vmf, &xfs_iomap_ops);
ret = block_page_mkwrite_return(ret);
@@ -1059,7 +1059,7 @@ xfs_filemap_fault(
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
if (IS_DAX(inode))
- ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
+ ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops, NULL);
else
ret = filemap_fault(vmf);
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
@@ -1094,7 +1094,7 @@ xfs_filemap_huge_fault(
}
xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
- ret = dax_iomap_fault(vmf, pe_size, &xfs_iomap_ops);
+ ret = dax_iomap_fault(vmf, pe_size, &xfs_iomap_ops, NULL);
xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
if (vmf->flags & FAULT_FLAG_WRITE)
@@ -1130,7 +1130,7 @@ xfs_filemap_pfn_mkwrite(
if (vmf->pgoff >= size)
ret = VM_FAULT_SIGBUS;
else if (IS_DAX(inode))
- ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops);
+ ret = dax_iomap_fault(vmf, PE_SIZE_PTE, &xfs_iomap_ops, NULL);
xfs_iunlock(ip, XFS_MMAPLOCK_SHARED);
sb_end_pagefault(inode->i_sb);
return ret;
diff --git a/include/linux/dax.h b/include/linux/dax.h
index d0e32729ad1e..8f493d9879f7 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -91,7 +91,7 @@ void dax_write_cache(struct dax_device *dax_dev, bool wc);
ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
const struct iomap_ops *ops);
int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
- const struct iomap_ops *ops);
+ const struct iomap_ops *ops, pfn_t *pfnp);
int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
pgoff_t index);
--
2.12.3
On Thu, Aug 17, 2017 at 06:08:11PM +0200, Jan Kara wrote:
> For synchronous page fault dax_iomap_fault() will need to return PFN
> which will then need to inserted into page tables after fsync()
> completes. Add necessary parameter to dax_iomap_fault().
>
> Signed-off-by: Jan Kara <[email protected]>
Yep, this seems like a nice, straightforward way of doing things. I like this
better than the vmf->orig_pte solution from the previous RFC.
Reviewed-by: Ross Zwisler <[email protected]>
> @@ -1416,6 +1416,7 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
> * @vmf: The description of the fault
> * @pe_size: Size of the page to fault in
> * @ops: Iomap ops passed from the file system
> + * @pfnp: PFN to insert for synchronous faults if fsync is required
> *
> * When a page fault occurs, filesystems may call this helper in
> * their fault handler for DAX files. dax_iomap_fault() assumes the caller
> @@ -1423,13 +1424,13 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
> * successfully.
> */
> int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
> - const struct iomap_ops *ops)
> + const struct iomap_ops *ops, pfn_t *pfnp)
Please keep the iomap_ops argument the last one for the exported
function (and probably all others for consistency).
Otherwise looks good:
Reviewed-by: Christoph Hellwig <[email protected]>
On Wed 23-08-17 11:34:00, Christoph Hellwig wrote:
> > @@ -1416,6 +1416,7 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
> > * @vmf: The description of the fault
> > * @pe_size: Size of the page to fault in
> > * @ops: Iomap ops passed from the file system
> > + * @pfnp: PFN to insert for synchronous faults if fsync is required
> > *
> > * When a page fault occurs, filesystems may call this helper in
> > * their fault handler for DAX files. dax_iomap_fault() assumes the caller
> > @@ -1423,13 +1424,13 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf,
> > * successfully.
> > */
> > int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
> > - const struct iomap_ops *ops)
> > + const struct iomap_ops *ops, pfn_t *pfnp)
>
> Please keep the iomap_ops argument the last one for the exported
> function (and probably all others for consistency).
Hum, I wanted the output argument to be the last one. But I don't care
much. Swapped.
> Otherwise looks good:
>
> Reviewed-by: Christoph Hellwig <[email protected]>
Thanks!
Honza
--
Jan Kara <[email protected]>
SUSE Labs, CR