[PATCH] Turn do_sync_file_range() into do_sync_mapping_range()

[PATCH] Turn do_sync_file_range() into do_sync_mapping_range()

[Mark Fasheh]

do_sync_file_range() accepts a file * from which it takes an address_space
to sync. Abstract out the bulk of the function into do_sync_mapping_range()
which takes the address_space directly. This way callers who want to sync an
address_space directly can take advantage of the functionality provided.

do_sync_file_range() is preserved as a 3 line wrapper around
do_sync_mapping_range().

Ocfs2 in particular would like to use this to initiate a sync of a specific
inode range during truncate, where a file * may not be available.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
---
 fs/sync.c          |   16 ++++------------
 include/linux/fs.h |   11 +++++++++--
 2 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/fs/sync.c b/fs/sync.c
index d0feff6..b0675ec 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -239,19 +239,11 @@ out:
 /*
  * `endbyte' is inclusive
  */
-int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte,
-			unsigned int flags)
+int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
+			  loff_t endbyte, unsigned int flags)
 {
-	int ret;
-	struct address_space *mapping;
-
-	mapping = file->f_mapping;
-	if (!mapping) {
-		ret = -EINVAL;
-		goto out;
-	}
+	int ret = 0;
 
-	ret = 0;
 	if (flags & SYNC_FILE_RANGE_WAIT_BEFORE) {
 		ret = wait_on_page_writeback_range(mapping,
 					offset >> PAGE_CACHE_SHIFT,
@@ -275,4 +267,4 @@ int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte,
 out:
 	return ret;
 }
-EXPORT_SYMBOL_GPL(do_sync_file_range);
+EXPORT_SYMBOL_GPL(do_sync_mapping_range);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1410e53..7fa4473 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -842,8 +842,15 @@ extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg);
 extern int fcntl_getlease(struct file *filp);
 
 /* fs/sync.c */
-extern int do_sync_file_range(struct file *file, loff_t offset, loff_t endbyte,
-			unsigned int flags);
+extern int do_sync_mapping_range(struct address_space *mapping, loff_t offset,
+			loff_t endbyte, unsigned int flags);
+static inline int do_sync_file_range(struct file *file, loff_t offset,
+				     loff_t endbyte, unsigned int flags)
+{
+	if (file->f_mapping == NULL)
+		return -EINVAL;
+	return do_sync_mapping_range(file->f_mapping, offset, endbyte, flags);
+}
 
 /* fs/locks.c */
 extern void locks_init_lock(struct file_lock *);
-- 
1.4.4.2

Re: [PATCH] Turn do_sync_file_range() into do_sync_mapping_range()

[Andrew Morton]

On Tue, 20 Mar 2007 14:46:26 -0700 Mark Fasheh <mark.fasheh@oracle.com> wrote:

> do_sync_file_range() accepts a file * from which it takes an address_space
> to sync. Abstract out the bulk of the function into do_sync_mapping_range()
> which takes the address_space directly. This way callers who want to sync an
> address_space directly can take advantage of the functionality provided.
> 
> do_sync_file_range() is preserved as a 3 line wrapper around
> do_sync_mapping_range().
> 
> Ocfs2 in particular would like to use this to initiate a sync of a specific
> inode range during truncate, where a file * may not be available.

I think we can remove do_sync_file_range() altogether?

Re: [PATCH] Turn do_sync_file_range() into do_sync_mapping_range()

[Christoph Hellwig]

On Tue, Mar 20, 2007 at 02:46:26PM -0700, Mark Fasheh wrote:
> do_sync_file_range() accepts a file * from which it takes an address_space
> to sync. Abstract out the bulk of the function into do_sync_mapping_range()
> which takes the address_space directly. This way callers who want to sync an
> address_space directly can take advantage of the functionality provided.
> 
> do_sync_file_range() is preserved as a 3 line wrapper around
> do_sync_mapping_range().
> 
> Ocfs2 in particular would like to use this to initiate a sync of a specific
> inode range during truncate, where a file * may not be available.

Looks good to me, but I agree with Andrew that we should simply
kill do_sync_file_range, espcially as at least one of the callers
has file->f_mapping guaranteed != NULL;

Re: [PATCH] Turn do_sync_file_range() into do_sync_mapping_range()

[Mark Fasheh]

On Wed, Mar 21, 2007 at 02:44:26PM +0000, Christoph Hellwig wrote:
> On Tue, Mar 20, 2007 at 02:46:26PM -0700, Mark Fasheh wrote:
> > do_sync_file_range() accepts a file * from which it takes an address_space
> > to sync. Abstract out the bulk of the function into do_sync_mapping_range()
> > which takes the address_space directly. This way callers who want to sync an
> > address_space directly can take advantage of the functionality provided.
> > 
> > do_sync_file_range() is preserved as a 3 line wrapper around
> > do_sync_mapping_range().
> > 
> > Ocfs2 in particular would like to use this to initiate a sync of a specific
> > inode range during truncate, where a file * may not be available.
> 
> Looks good to me, but I agree with Andrew that we should simply
> kill do_sync_file_range, espcially as at least one of the callers
> has file->f_mapping guaranteed != NULL;

Ok - I'll post an updated patch series today. Thank you all for taking the
time to look at this.
	--Mark

--
Mark Fasheh
Senior Software Developer, Oracle
mark.fasheh@oracle.com