[PATCH 1/2] dax: some small updates to dax.txt documentation

[PATCH 1/2] dax: some small updates to dax.txt documentation

[Ross Zwisler]

These are originally from Matthew Wilcox and were part of his huge
"mm,fs,dax: Change ->pmd_fault to ->huge_fault" patch that was part of PUD
support.

I'm breaking these small changes out as they stand on their own and add
useful information to Documentation/filesystems/dax.txt.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 Documentation/filesystems/dax.txt | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt
index ce4587d..0c16a22 100644
--- a/Documentation/filesystems/dax.txt
+++ b/Documentation/filesystems/dax.txt
@@ -49,6 +49,7 @@ These block devices may be used for inspiration:
 - axonram: Axon DDR2 device driver
 - brd: RAM backed block device driver
 - dcssblk: s390 dcss block device driver
+- pmem: NVDIMM persistent memory driver
 
 
 Implementation Tips for Filesystem Writers
@@ -75,8 +76,9 @@ calls to get_block() (for example by a page-fault racing with a read()
 or a write()) work correctly.
 
 These filesystems may be used for inspiration:
-- ext2: the second extended filesystem, see Documentation/filesystems/ext2.txt
-- ext4: the fourth extended filesystem, see Documentation/filesystems/ext4.txt
+- ext2: see Documentation/filesystems/ext2.txt
+- ext4: see Documentation/filesystems/ext4.txt
+- xfs:  see Documentation/filesystems/xfs.txt
 
 
 Handling Media Errors
-- 
2.9.0

[PATCH 2/2] dax: remote unused fault wrappers

[Ross Zwisler]

Remove the unused wrappers dax_fault() and dax_pmd_fault().  After this
removal, rename __dax_fault() and __dax_pmd_fault() to dax_fault() and
dax_pmd_fault() respectively, and update all callers.

The dax_fault() and dax_pmd_fault() wrappers were initially intended to
capture some filesystem independent functionality around page faults
(calling sb_start_pagefault() & sb_end_pagefault(), updating file
mtime and ctime).  However, the following commits:

commit 5726b27b09cc ("ext2: Add locking for DAX faults")
commit ea3d7209ca01 ("ext4: fix races between page faults and hole punching")

Added locking to the ext2 and ext4 filesystems after these common
operations but before __dax_fault() and __dax_pmd_fault() were called.
This means that these wrappers are no longer used, and are unlikely to be
used in the future.  XFS has had locking analogous to what was recently
added to ext2 and ext4 since DAX support was initially introduced by:

commit 6b698edeeef0 ("xfs: add DAX file operations support")

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
---
 fs/dax.c            | 73 ++++++++++-------------------------------------------
 fs/ext2/file.c      |  4 +--
 fs/ext4/file.c      |  4 +--
 fs/xfs/xfs_file.c   |  6 ++---
 include/linux/dax.h |  5 ----
 5 files changed, 21 insertions(+), 71 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index e207f8f..432b9e6 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -819,16 +819,16 @@ static int dax_insert_mapping(struct address_space *mapping,
 }
 
 /**
- * __dax_fault - handle a page fault on a DAX file
+ * dax_fault - handle a page fault on a DAX file
  * @vma: The virtual memory area where the fault occurred
  * @vmf: The description of the fault
  * @get_block: The filesystem method used to translate file offsets to blocks
  *
  * When a page fault occurs, filesystems may call this helper in their
- * fault handler for DAX files. __dax_fault() assumes the caller has done all
+ * fault handler for DAX files. dax_fault() assumes the caller has done all
  * the necessary locking for the page fault to proceed successfully.
  */
-int __dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
+int dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
 			get_block_t get_block)
 {
 	struct file *file = vma->vm_file;
@@ -913,33 +913,6 @@ int __dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
 		return VM_FAULT_SIGBUS | major;
 	return VM_FAULT_NOPAGE | major;
 }
-EXPORT_SYMBOL(__dax_fault);
-
-/**
- * dax_fault - handle a page fault on a DAX file
- * @vma: The virtual memory area where the fault occurred
- * @vmf: The description of the fault
- * @get_block: The filesystem method used to translate file offsets to blocks
- *
- * When a page fault occurs, filesystems may call this helper in their
- * fault handler for DAX files.
- */
-int dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
-	      get_block_t get_block)
-{
-	int result;
-	struct super_block *sb = file_inode(vma->vm_file)->i_sb;
-
-	if (vmf->flags & FAULT_FLAG_WRITE) {
-		sb_start_pagefault(sb);
-		file_update_time(vma->vm_file);
-	}
-	result = __dax_fault(vma, vmf, get_block);
-	if (vmf->flags & FAULT_FLAG_WRITE)
-		sb_end_pagefault(sb);
-
-	return result;
-}
 EXPORT_SYMBOL_GPL(dax_fault);
 
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
@@ -967,7 +940,16 @@ static void __dax_dbg(struct buffer_head *bh, unsigned long address,
 
 #define dax_pmd_dbg(bh, address, reason)	__dax_dbg(bh, address, reason, "dax_pmd")
 
-int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
+/**
+ * dax_pmd_fault - handle a PMD fault on a DAX file
+ * @vma: The virtual memory area where the fault occurred
+ * @vmf: The description of the fault
+ * @get_block: The filesystem method used to translate file offsets to blocks
+ *
+ * When a page fault occurs, filesystems may call this helper in their
+ * pmd_fault handler for DAX files.
+ */
+int dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 		pmd_t *pmd, unsigned int flags, get_block_t get_block)
 {
 	struct file *file = vma->vm_file;
@@ -1119,7 +1101,7 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 		 *
 		 * The PMD path doesn't have an equivalent to
 		 * dax_pfn_mkwrite(), though, so for a read followed by a
-		 * write we traverse all the way through __dax_pmd_fault()
+		 * write we traverse all the way through dax_pmd_fault()
 		 * twice.  This means we can just skip inserting a radix tree
 		 * entry completely on the initial read and just wait until
 		 * the write to insert a dirty entry.
@@ -1148,33 +1130,6 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
 	result = VM_FAULT_FALLBACK;
 	goto out;
 }
-EXPORT_SYMBOL_GPL(__dax_pmd_fault);
-
-/**
- * dax_pmd_fault - handle a PMD fault on a DAX file
- * @vma: The virtual memory area where the fault occurred
- * @vmf: The description of the fault
- * @get_block: The filesystem method used to translate file offsets to blocks
- *
- * When a page fault occurs, filesystems may call this helper in their
- * pmd_fault handler for DAX files.
- */
-int dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
-			pmd_t *pmd, unsigned int flags, get_block_t get_block)
-{
-	int result;
-	struct super_block *sb = file_inode(vma->vm_file)->i_sb;
-
-	if (flags & FAULT_FLAG_WRITE) {
-		sb_start_pagefault(sb);
-		file_update_time(vma->vm_file);
-	}
-	result = __dax_pmd_fault(vma, address, pmd, flags, get_block);
-	if (flags & FAULT_FLAG_WRITE)
-		sb_end_pagefault(sb);
-
-	return result;
-}
 EXPORT_SYMBOL_GPL(dax_pmd_fault);
 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index 868c023..5efeefe 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -51,7 +51,7 @@ static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	}
 	down_read(&ei->dax_sem);
 
-	ret = __dax_fault(vma, vmf, ext2_get_block);
+	ret = dax_fault(vma, vmf, ext2_get_block);
 
 	up_read(&ei->dax_sem);
 	if (vmf->flags & FAULT_FLAG_WRITE)
@@ -72,7 +72,7 @@ static int ext2_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
 	}
 	down_read(&ei->dax_sem);
 
-	ret = __dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block);
+	ret = dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block);
 
 	up_read(&ei->dax_sem);
 	if (flags & FAULT_FLAG_WRITE)
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index df44c87..6664f9c 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -202,7 +202,7 @@ static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	if (IS_ERR(handle))
 		result = VM_FAULT_SIGBUS;
 	else
-		result = __dax_fault(vma, vmf, ext4_dax_get_block);
+		result = dax_fault(vma, vmf, ext4_dax_get_block);
 
 	if (write) {
 		if (!IS_ERR(handle))
@@ -237,7 +237,7 @@ static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
 	if (IS_ERR(handle))
 		result = VM_FAULT_SIGBUS;
 	else
-		result = __dax_pmd_fault(vma, addr, pmd, flags,
+		result = dax_pmd_fault(vma, addr, pmd, flags,
 					 ext4_dax_get_block);
 
 	if (write) {
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 47fc632..1b3dc9dd 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -1551,7 +1551,7 @@ xfs_filemap_page_mkwrite(
 	xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
 
 	if (IS_DAX(inode)) {
-		ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault);
+		ret = dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault);
 	} else {
 		ret = block_page_mkwrite(vma, vmf, xfs_get_blocks);
 		ret = block_page_mkwrite_return(ret);
@@ -1585,7 +1585,7 @@ xfs_filemap_fault(
 		 * changes to xfs_get_blocks_direct() to map unwritten extent
 		 * ioend for conversion on read-only mappings.
 		 */
-		ret = __dax_fault(vma, vmf, xfs_get_blocks_dax_fault);
+		ret = dax_fault(vma, vmf, xfs_get_blocks_dax_fault);
 	} else
 		ret = filemap_fault(vma, vmf);
 	xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
@@ -1622,7 +1622,7 @@ xfs_filemap_pmd_fault(
 	}
 
 	xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
-	ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault);
+	ret = dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault);
 	xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
 
 	if (flags & FAULT_FLAG_WRITE)
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 43d5f0b..9c6dc77 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -14,7 +14,6 @@ ssize_t dax_do_io(struct kiocb *, struct inode *, struct iov_iter *,
 int dax_zero_page_range(struct inode *, loff_t from, unsigned len, get_block_t);
 int dax_truncate_page(struct inode *, loff_t from, get_block_t);
 int dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
-int __dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
 void dax_wake_mapping_entry_waiter(struct address_space *mapping,
 				   pgoff_t index, bool wake_all);
@@ -46,19 +45,15 @@ static inline int __dax_zero_page_range(struct block_device *bdev,
 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
 int dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *,
 				unsigned int flags, get_block_t);
-int __dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *,
-				unsigned int flags, get_block_t);
 #else
 static inline int dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
 				pmd_t *pmd, unsigned int flags, get_block_t gb)
 {
 	return VM_FAULT_FALLBACK;
 }
-#define __dax_pmd_fault dax_pmd_fault
 #endif
 int dax_pfn_mkwrite(struct vm_area_struct *, struct vm_fault *);
 #define dax_mkwrite(vma, vmf, gb)	dax_fault(vma, vmf, gb)
-#define __dax_mkwrite(vma, vmf, gb)	__dax_fault(vma, vmf, gb)
 
 static inline bool vma_is_dax(struct vm_area_struct *vma)
 {
-- 
2.9.0

Re: [PATCH 2/2] dax: remote unused fault wrappers

[Jan Kara]

On Thu 14-07-16 15:40:49, Ross Zwisler wrote:
> Remove the unused wrappers dax_fault() and dax_pmd_fault().  After this
> removal, rename __dax_fault() and __dax_pmd_fault() to dax_fault() and
> dax_pmd_fault() respectively, and update all callers.
> 
> The dax_fault() and dax_pmd_fault() wrappers were initially intended to
> capture some filesystem independent functionality around page faults
> (calling sb_start_pagefault() & sb_end_pagefault(), updating file
> mtime and ctime).  However, the following commits:
> 
> commit 5726b27b09cc ("ext2: Add locking for DAX faults")
> commit ea3d7209ca01 ("ext4: fix races between page faults and hole punching")
> 
> Added locking to the ext2 and ext4 filesystems after these common
> operations but before __dax_fault() and __dax_pmd_fault() were called.
> This means that these wrappers are no longer used, and are unlikely to be
> used in the future.  XFS has had locking analogous to what was recently
> added to ext2 and ext4 since DAX support was initially introduced by:
> 
> commit 6b698edeeef0 ("xfs: add DAX file operations support")
> 
> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>

The patch looks good. You can add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> diff --git a/fs/dax.c b/fs/dax.c
> index e207f8f..432b9e6 100644
> --- a/fs/dax.c
> +++ b/fs/dax.c
> @@ -819,16 +819,16 @@ static int dax_insert_mapping(struct address_space *mapping,
>  }
>  
>  /**
> - * __dax_fault - handle a page fault on a DAX file
> + * dax_fault - handle a page fault on a DAX file
>   * @vma: The virtual memory area where the fault occurred
>   * @vmf: The description of the fault
>   * @get_block: The filesystem method used to translate file offsets to blocks
>   *
>   * When a page fault occurs, filesystems may call this helper in their
> - * fault handler for DAX files. __dax_fault() assumes the caller has done all
> + * fault handler for DAX files. dax_fault() assumes the caller has done all
>   * the necessary locking for the page fault to proceed successfully.
>   */
> -int __dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
> +int dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
>  			get_block_t get_block)
>  {
>  	struct file *file = vma->vm_file;
> @@ -913,33 +913,6 @@ int __dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
>  		return VM_FAULT_SIGBUS | major;
>  	return VM_FAULT_NOPAGE | major;
>  }
> -EXPORT_SYMBOL(__dax_fault);
> -
> -/**
> - * dax_fault - handle a page fault on a DAX file
> - * @vma: The virtual memory area where the fault occurred
> - * @vmf: The description of the fault
> - * @get_block: The filesystem method used to translate file offsets to blocks
> - *
> - * When a page fault occurs, filesystems may call this helper in their
> - * fault handler for DAX files.
> - */
> -int dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf,
> -	      get_block_t get_block)
> -{
> -	int result;
> -	struct super_block *sb = file_inode(vma->vm_file)->i_sb;
> -
> -	if (vmf->flags & FAULT_FLAG_WRITE) {
> -		sb_start_pagefault(sb);
> -		file_update_time(vma->vm_file);
> -	}
> -	result = __dax_fault(vma, vmf, get_block);
> -	if (vmf->flags & FAULT_FLAG_WRITE)
> -		sb_end_pagefault(sb);
> -
> -	return result;
> -}
>  EXPORT_SYMBOL_GPL(dax_fault);
>  
>  #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
> @@ -967,7 +940,16 @@ static void __dax_dbg(struct buffer_head *bh, unsigned long address,
>  
>  #define dax_pmd_dbg(bh, address, reason)	__dax_dbg(bh, address, reason, "dax_pmd")
>  
> -int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
> +/**
> + * dax_pmd_fault - handle a PMD fault on a DAX file
> + * @vma: The virtual memory area where the fault occurred
> + * @vmf: The description of the fault
> + * @get_block: The filesystem method used to translate file offsets to blocks
> + *
> + * When a page fault occurs, filesystems may call this helper in their
> + * pmd_fault handler for DAX files.
> + */
> +int dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
>  		pmd_t *pmd, unsigned int flags, get_block_t get_block)
>  {
>  	struct file *file = vma->vm_file;
> @@ -1119,7 +1101,7 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
>  		 *
>  		 * The PMD path doesn't have an equivalent to
>  		 * dax_pfn_mkwrite(), though, so for a read followed by a
> -		 * write we traverse all the way through __dax_pmd_fault()
> +		 * write we traverse all the way through dax_pmd_fault()
>  		 * twice.  This means we can just skip inserting a radix tree
>  		 * entry completely on the initial read and just wait until
>  		 * the write to insert a dirty entry.
> @@ -1148,33 +1130,6 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
>  	result = VM_FAULT_FALLBACK;
>  	goto out;
>  }
> -EXPORT_SYMBOL_GPL(__dax_pmd_fault);
> -
> -/**
> - * dax_pmd_fault - handle a PMD fault on a DAX file
> - * @vma: The virtual memory area where the fault occurred
> - * @vmf: The description of the fault
> - * @get_block: The filesystem method used to translate file offsets to blocks
> - *
> - * When a page fault occurs, filesystems may call this helper in their
> - * pmd_fault handler for DAX files.
> - */
> -int dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
> -			pmd_t *pmd, unsigned int flags, get_block_t get_block)
> -{
> -	int result;
> -	struct super_block *sb = file_inode(vma->vm_file)->i_sb;
> -
> -	if (flags & FAULT_FLAG_WRITE) {
> -		sb_start_pagefault(sb);
> -		file_update_time(vma->vm_file);
> -	}
> -	result = __dax_pmd_fault(vma, address, pmd, flags, get_block);
> -	if (flags & FAULT_FLAG_WRITE)
> -		sb_end_pagefault(sb);
> -
> -	return result;
> -}
>  EXPORT_SYMBOL_GPL(dax_pmd_fault);
>  #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>  
> diff --git a/fs/ext2/file.c b/fs/ext2/file.c
> index 868c023..5efeefe 100644
> --- a/fs/ext2/file.c
> +++ b/fs/ext2/file.c
> @@ -51,7 +51,7 @@ static int ext2_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
>  	}
>  	down_read(&ei->dax_sem);
>  
> -	ret = __dax_fault(vma, vmf, ext2_get_block);
> +	ret = dax_fault(vma, vmf, ext2_get_block);
>  
>  	up_read(&ei->dax_sem);
>  	if (vmf->flags & FAULT_FLAG_WRITE)
> @@ -72,7 +72,7 @@ static int ext2_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
>  	}
>  	down_read(&ei->dax_sem);
>  
> -	ret = __dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block);
> +	ret = dax_pmd_fault(vma, addr, pmd, flags, ext2_get_block);
>  
>  	up_read(&ei->dax_sem);
>  	if (flags & FAULT_FLAG_WRITE)
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index df44c87..6664f9c 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -202,7 +202,7 @@ static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
>  	if (IS_ERR(handle))
>  		result = VM_FAULT_SIGBUS;
>  	else
> -		result = __dax_fault(vma, vmf, ext4_dax_get_block);
> +		result = dax_fault(vma, vmf, ext4_dax_get_block);
>  
>  	if (write) {
>  		if (!IS_ERR(handle))
> @@ -237,7 +237,7 @@ static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
>  	if (IS_ERR(handle))
>  		result = VM_FAULT_SIGBUS;
>  	else
> -		result = __dax_pmd_fault(vma, addr, pmd, flags,
> +		result = dax_pmd_fault(vma, addr, pmd, flags,
>  					 ext4_dax_get_block);
>  
>  	if (write) {
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 47fc632..1b3dc9dd 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -1551,7 +1551,7 @@ xfs_filemap_page_mkwrite(
>  	xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
>  
>  	if (IS_DAX(inode)) {
> -		ret = __dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault);
> +		ret = dax_mkwrite(vma, vmf, xfs_get_blocks_dax_fault);
>  	} else {
>  		ret = block_page_mkwrite(vma, vmf, xfs_get_blocks);
>  		ret = block_page_mkwrite_return(ret);
> @@ -1585,7 +1585,7 @@ xfs_filemap_fault(
>  		 * changes to xfs_get_blocks_direct() to map unwritten extent
>  		 * ioend for conversion on read-only mappings.
>  		 */
> -		ret = __dax_fault(vma, vmf, xfs_get_blocks_dax_fault);
> +		ret = dax_fault(vma, vmf, xfs_get_blocks_dax_fault);
>  	} else
>  		ret = filemap_fault(vma, vmf);
>  	xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
> @@ -1622,7 +1622,7 @@ xfs_filemap_pmd_fault(
>  	}
>  
>  	xfs_ilock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
> -	ret = __dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault);
> +	ret = dax_pmd_fault(vma, addr, pmd, flags, xfs_get_blocks_dax_fault);
>  	xfs_iunlock(XFS_I(inode), XFS_MMAPLOCK_SHARED);
>  
>  	if (flags & FAULT_FLAG_WRITE)
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 43d5f0b..9c6dc77 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -14,7 +14,6 @@ ssize_t dax_do_io(struct kiocb *, struct inode *, struct iov_iter *,
>  int dax_zero_page_range(struct inode *, loff_t from, unsigned len, get_block_t);
>  int dax_truncate_page(struct inode *, loff_t from, get_block_t);
>  int dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
> -int __dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
>  int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
>  void dax_wake_mapping_entry_waiter(struct address_space *mapping,
>  				   pgoff_t index, bool wake_all);
> @@ -46,19 +45,15 @@ static inline int __dax_zero_page_range(struct block_device *bdev,
>  #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
>  int dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *,
>  				unsigned int flags, get_block_t);
> -int __dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *,
> -				unsigned int flags, get_block_t);
>  #else
>  static inline int dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
>  				pmd_t *pmd, unsigned int flags, get_block_t gb)
>  {
>  	return VM_FAULT_FALLBACK;
>  }
> -#define __dax_pmd_fault dax_pmd_fault
>  #endif
>  int dax_pfn_mkwrite(struct vm_area_struct *, struct vm_fault *);
>  #define dax_mkwrite(vma, vmf, gb)	dax_fault(vma, vmf, gb)
> -#define __dax_mkwrite(vma, vmf, gb)	__dax_fault(vma, vmf, gb)
>  
>  static inline bool vma_is_dax(struct vm_area_struct *vma)
>  {
> -- 
> 2.9.0
> 
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH 1/2] dax: some small updates to dax.txt documentation

[Jonathan Corbet]

On Thu, 14 Jul 2016 15:40:48 -0600
Ross Zwisler <ross.zwisler@linux.intel.com> wrote:

> These are originally from Matthew Wilcox and were part of his huge
> "mm,fs,dax: Change ->pmd_fault to ->huge_fault" patch that was part of PUD
> support.
> 
> I'm breaking these small changes out as they stand on their own and add
> useful information to Documentation/filesystems/dax.txt.

So how were you thinking of routing these?  I can take the docs fix, of
course, but part 2 is a bit out of my turf.  If you want to route them
together via another tree that's fine, just let me know.

Thanks,

jon

Re: [PATCH 1/2] dax: some small updates to dax.txt documentation

[Andrew Morton]

On Wed, 20 Jul 2016 17:13:02 -0600 Jonathan Corbet <corbet@lwn.net> wrote:

> On Thu, 14 Jul 2016 15:40:48 -0600
> Ross Zwisler <ross.zwisler@linux.intel.com> wrote:
> 
> > These are originally from Matthew Wilcox and were part of his huge
> > "mm,fs,dax: Change ->pmd_fault to ->huge_fault" patch that was part of PUD
> > support.
> > 
> > I'm breaking these small changes out as they stand on their own and add
> > useful information to Documentation/filesystems/dax.txt.
> 
> So how were you thinking of routing these?  I can take the docs fix, of
> course, but part 2 is a bit out of my turf.  If you want to route them
> together via another tree that's fine, just let me know.

I have them queued.  You were cc'ed on the commit!

Re: [PATCH 1/2] dax: some small updates to dax.txt documentation

[Jonathan Corbet]

On Wed, 20 Jul 2016 16:18:57 -0700
Andrew Morton <akpm@linux-foundation.org> wrote:

> > So how were you thinking of routing these?  I can take the docs fix, of
> > course, but part 2 is a bit out of my turf.  If you want to route them
> > together via another tree that's fine, just let me know.  
> 
> I have them queued.  You were cc'ed on the commit!

Interesting, I can't find that cc in my archive anywhere.  It seems it
went astray somewhere?

Thanks,

jon