[PATCH 01/17] vfs: Introduce filemap_fdatawait_range

[PATCH 01/17] vfs: Introduce filemap_fdatawait_range

[Jan Kara]

This simple helper saves some filesystems conversion from byte offset
to page numbers and also makes the fdata* interface more complete.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 include/linux/fs.h |    2 ++
 mm/filemap.c       |   20 ++++++++++++++++++++
 2 files changed, 22 insertions(+), 0 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 67888a9..cb365ad 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2076,6 +2076,8 @@ extern int write_inode_now(struct inode *, int);
 extern int filemap_fdatawrite(struct address_space *);
 extern int filemap_flush(struct address_space *);
 extern int filemap_fdatawait(struct address_space *);
+extern int filemap_fdatawait_range(struct address_space *, loff_t lstart,
+				   loff_t lend);
 extern int filemap_write_and_wait(struct address_space *mapping);
 extern int filemap_write_and_wait_range(struct address_space *mapping,
 				        loff_t lstart, loff_t lend);
diff --git a/mm/filemap.c b/mm/filemap.c
index ccea3b6..65b2e50 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -307,6 +307,26 @@ int wait_on_page_writeback_range(struct address_space *mapping,
 }
 
 /**
+ * filemap_fdatawait_range - wait for all under-writeback pages to complete in a given range
+ * @mapping: address space structure to wait for
+ * @start:	offset in bytes where the range starts
+ * @end:	offset in bytes where the range ends (inclusive)
+ *
+ * Walk the list of under-writeback pages of the given address space
+ * in the given range and wait for all of them.
+ *
+ * This is just a simple wrapper so that callers don't have to convert offsets
+ * to page indexes themselves
+ */
+int filemap_fdatawait_range(struct address_space *mapping, loff_t start,
+			    loff_t end)
+{
+	return wait_on_page_writeback_range(mapping, start >> PAGE_CACHE_SHIFT,
+					    end >> PAGE_CACHE_SHIFT);
+}
+EXPORT_SYMBOL(filemap_fdatawait_range);
+
+/**
  * sync_page_range - write and wait on all pages in the passed range
  * @inode:	target inode
  * @mapping:	target address_space
-- 
1.6.0.2

[PATCH 02/17] vfs: Export __generic_file_aio_write() and add some comments

[Jan Kara]

Rename __generic_file_aio_write_nolock() to __generic_file_aio_write(), add
comments to write helpers explaining how they should be used and export
__generic_file_aio_write() since it will be used by some filesystems.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 include/linux/fs.h |    2 +
 mm/filemap.c       |   57 +++++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 52 insertions(+), 7 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index cb365ad..1edd159 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2195,6 +2195,8 @@ extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
+extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
+		loff_t *);
 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
 extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
 		unsigned long, loff_t);
diff --git a/mm/filemap.c b/mm/filemap.c
index 65b2e50..554a396 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2368,9 +2368,27 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 }
 EXPORT_SYMBOL(generic_file_buffered_write);
 
-static ssize_t
-__generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
-				unsigned long nr_segs, loff_t *ppos)
+/**
+ * __generic_file_aio_write - write data to a file
+ * @iocb:	IO state structure (file, offset, etc.)
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @ppos:	position where to write
+ *
+ * This function does all the work needed for actually writing data to a
+ * file. It does all basic checks, removes SUID from the file, updates
+ * modification times and calls proper subroutines depending on whether we
+ * do direct IO or a standard buffered write.
+ *
+ * It expects i_mutex to be grabbed unless we work on a block device or similar
+ * object which does not need locking at all.
+ *
+ * This function does *not* take care of syncing data in case of O_SYNC write.
+ * A caller has to handle it. This is mainly due to the fact that we want to
+ * avoid syncing under i_mutex.
+ */
+ssize_t __generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+				 unsigned long nr_segs, loff_t *ppos)
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space * mapping = file->f_mapping;
@@ -2467,7 +2485,23 @@ out:
 	current->backing_dev_info = NULL;
 	return written ? written : err;
 }
+EXPORT_SYMBOL(__generic_file_aio_write);
+
 
+/**
+ * generic_file_aio_write_nolock - write data, usually to a device
+ * @iocb:	IO state structure
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @pos:	position in file where to write
+ *
+ * This is a wrapper around __generic_file_aio_write() which takes care of
+ * syncing the file in case of O_SYNC file. It does not take i_mutex for the
+ * write itself but may do so during syncing. It is meant for users like block
+ * devices which do not need i_mutex during write. If your filesystem needs to
+ * do a write but already holds i_mutex, use __generic_file_aio_write()
+ * directly and then sync the file like generic_file_aio_write().
+ */
 ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 		const struct iovec *iov, unsigned long nr_segs, loff_t pos)
 {
@@ -2478,8 +2512,7 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	BUG_ON(iocb->ki_pos != pos);
 
-	ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs,
-			&iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
 	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
@@ -2492,6 +2525,17 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 }
 EXPORT_SYMBOL(generic_file_aio_write_nolock);
 
+/**
+ * generic_file_aio_write - write data to a file
+ * @iocb:	IO state structure
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @pos:	position in file where to write
+ *
+ * This is a wrapper around __generic_file_aio_write() to be used by most
+ * filesystems. It takes care of syncing the file in case of O_SYNC file
+ * and acquires i_mutex as needed.
+ */
 ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
@@ -2503,8 +2547,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	BUG_ON(iocb->ki_pos != pos);
 
 	mutex_lock(&inode->i_mutex);
-	ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs,
-			&iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
 	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-- 
1.6.0.2

[Ocfs2-devel] [PATCH 02/17] vfs: Export __generic_file_aio_write() and add some comments

[Jan Kara]

Rename __generic_file_aio_write_nolock() to __generic_file_aio_write(), add
comments to write helpers explaining how they should be used and export
__generic_file_aio_write() since it will be used by some filesystems.

CC: ocfs2-devel at oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 include/linux/fs.h |    2 +
 mm/filemap.c       |   57 +++++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 52 insertions(+), 7 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index cb365ad..1edd159 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2195,6 +2195,8 @@ extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
 extern int file_read_actor(read_descriptor_t * desc, struct page *page, unsigned long offset, unsigned long size);
 int generic_write_checks(struct file *file, loff_t *pos, size_t *count, int isblk);
 extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsigned long, loff_t);
+extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
+		loff_t *);
 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
 extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
 		unsigned long, loff_t);
diff --git a/mm/filemap.c b/mm/filemap.c
index 65b2e50..554a396 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2368,9 +2368,27 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 }
 EXPORT_SYMBOL(generic_file_buffered_write);
 
-static ssize_t
-__generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
-				unsigned long nr_segs, loff_t *ppos)
+/**
+ * __generic_file_aio_write - write data to a file
+ * @iocb:	IO state structure (file, offset, etc.)
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @ppos:	position where to write
+ *
+ * This function does all the work needed for actually writing data to a
+ * file. It does all basic checks, removes SUID from the file, updates
+ * modification times and calls proper subroutines depending on whether we
+ * do direct IO or a standard buffered write.
+ *
+ * It expects i_mutex to be grabbed unless we work on a block device or similar
+ * object which does not need locking at all.
+ *
+ * This function does *not* take care of syncing data in case of O_SYNC write.
+ * A caller has to handle it. This is mainly due to the fact that we want to
+ * avoid syncing under i_mutex.
+ */
+ssize_t __generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
+				 unsigned long nr_segs, loff_t *ppos)
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space * mapping = file->f_mapping;
@@ -2467,7 +2485,23 @@ out:
 	current->backing_dev_info = NULL;
 	return written ? written : err;
 }
+EXPORT_SYMBOL(__generic_file_aio_write);
+
 
+/**
+ * generic_file_aio_write_nolock - write data, usually to a device
+ * @iocb:	IO state structure
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @pos:	position in file where to write
+ *
+ * This is a wrapper around __generic_file_aio_write() which takes care of
+ * syncing the file in case of O_SYNC file. It does not take i_mutex for the
+ * write itself but may do so during syncing. It is meant for users like block
+ * devices which do not need i_mutex during write. If your filesystem needs to
+ * do a write but already holds i_mutex, use __generic_file_aio_write()
+ * directly and then sync the file like generic_file_aio_write().
+ */
 ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 		const struct iovec *iov, unsigned long nr_segs, loff_t pos)
 {
@@ -2478,8 +2512,7 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	BUG_ON(iocb->ki_pos != pos);
 
-	ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs,
-			&iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
 	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
@@ -2492,6 +2525,17 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 }
 EXPORT_SYMBOL(generic_file_aio_write_nolock);
 
+/**
+ * generic_file_aio_write - write data to a file
+ * @iocb:	IO state structure
+ * @iov:	vector with data to write
+ * @nr_segs:	number of segments in the vector
+ * @pos:	position in file where to write
+ *
+ * This is a wrapper around __generic_file_aio_write() to be used by most
+ * filesystems. It takes care of syncing the file in case of O_SYNC file
+ * and acquires i_mutex as needed.
+ */
 ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
@@ -2503,8 +2547,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	BUG_ON(iocb->ki_pos != pos);
 
 	mutex_lock(&inode->i_mutex);
-	ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs,
-			&iocb->ki_pos);
+	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
 	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-- 
1.6.0.2

[PATCH 03/17] vfs: Remove syncing from generic_file_direct_write() and generic_file_buffered_write()

[Jan Kara]

generic_file_direct_write() and generic_file_buffered_write() called
generic_osync_inode() if it was called on O_SYNC file or IS_SYNC inode. But
this is superfluous since generic_file_aio_write() does the syncing as well.
Also XFS and OCFS2 which call these functions directly handle syncing
themselves. So let's have a single place where syncing happens:
generic_file_aio_write().

We slightly change the behavior by syncing only the range of file to which the
write happened for buffered writes but that should be all that is required.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 mm/filemap.c |   31 ++++---------------------------
 1 files changed, 4 insertions(+), 27 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 554a396..b523e42 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2187,20 +2187,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 		*ppos = end;
 	}
-
-	/*
-	 * Sync the fs metadata but not the minor inode changes and
-	 * of course not the data as we did direct DMA for the IO.
-	 * i_mutex is held, which protects generic_osync_inode() from
-	 * livelocking.  AIO O_DIRECT ops attempt to sync metadata here.
-	 */
 out:
-	if ((written >= 0 || written == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-		int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);
-		if (err < 0)
-			written = err;
-	}
 	return written;
 }
 EXPORT_SYMBOL(generic_file_direct_write);
@@ -2332,8 +2319,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
-	const struct address_space_operations *a_ops = mapping->a_ops;
-	struct inode *inode = mapping->host;
 	ssize_t status;
 	struct iov_iter i;
 
@@ -2343,16 +2328,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 	if (likely(status >= 0)) {
 		written += status;
 		*ppos = pos + status;
-
-		/*
-		 * For now, when the user asks for O_SYNC, we'll actually give
-		 * O_DSYNC
-		 */
-		if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			if (!a_ops->writepage || !is_sync_kiocb(iocb))
-				status = generic_osync_inode(inode, mapping,
-						OSYNC_METADATA|OSYNC_DATA);
-		}
   	}
 	
 	/*
@@ -2514,7 +2489,8 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range_nolock(inode, mapping, pos, ret);
@@ -2550,7 +2526,8 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range(inode, mapping, pos, ret);
-- 
1.6.0.2

[PATCH 03/17] vfs: Remove syncing from generic_file_direct_write() and generic_file_buffered_write()

[Jan Kara]

generic_file_direct_write() and generic_file_buffered_write() called
generic_osync_inode() if it was called on O_SYNC file or IS_SYNC inode. But
this is superfluous since generic_file_aio_write() does the syncing as well.
Also XFS and OCFS2 which call these functions directly handle syncing
themselves. So let's have a single place where syncing happens:
generic_file_aio_write().

We slightly change the behavior by syncing only the range of file to which the
write happened for buffered writes but that should be all that is required.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 mm/filemap.c |   31 ++++---------------------------
 1 files changed, 4 insertions(+), 27 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 554a396..b523e42 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2187,20 +2187,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 		*ppos = end;
 	}
-
-	/*
-	 * Sync the fs metadata but not the minor inode changes and
-	 * of course not the data as we did direct DMA for the IO.
-	 * i_mutex is held, which protects generic_osync_inode() from
-	 * livelocking.  AIO O_DIRECT ops attempt to sync metadata here.
-	 */
 out:
-	if ((written >= 0 || written == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-		int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);
-		if (err < 0)
-			written = err;
-	}
 	return written;
 }
 EXPORT_SYMBOL(generic_file_direct_write);
@@ -2332,8 +2319,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
-	const struct address_space_operations *a_ops = mapping->a_ops;
-	struct inode *inode = mapping->host;
 	ssize_t status;
 	struct iov_iter i;
 
@@ -2343,16 +2328,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 	if (likely(status >= 0)) {
 		written += status;
 		*ppos = pos + status;
-
-		/*
-		 * For now, when the user asks for O_SYNC, we'll actually give
-		 * O_DSYNC
-		 */
-		if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			if (!a_ops->writepage || !is_sync_kiocb(iocb))
-				status = generic_osync_inode(inode, mapping,
-						OSYNC_METADATA|OSYNC_DATA);
-		}
   	}
 	
 	/*
@@ -2514,7 +2489,8 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range_nolock(inode, mapping, pos, ret);
@@ -2550,7 +2526,8 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range(inode, mapping, pos, ret);
-- 
1.6.0.2

[PATCH 03/17] vfs: Remove syncing from generic_file_direct_write() and generic_file_buffered_write()

[Jan Kara]

generic_file_direct_write() and generic_file_buffered_write() called
generic_osync_inode() if it was called on O_SYNC file or IS_SYNC inode. But
this is superfluous since generic_file_aio_write() does the syncing as well.
Also XFS and OCFS2 which call these functions directly handle syncing
themselves. So let's have a single place where syncing happens:
generic_file_aio_write().

We slightly change the behavior by syncing only the range of file to which the
write happened for buffered writes but that should be all that is required.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 mm/filemap.c |   31 ++++---------------------------
 1 files changed, 4 insertions(+), 27 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 554a396..b523e42 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2187,20 +2187,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 		*ppos = end;
 	}
-
-	/*
-	 * Sync the fs metadata but not the minor inode changes and
-	 * of course not the data as we did direct DMA for the IO.
-	 * i_mutex is held, which protects generic_osync_inode() from
-	 * livelocking.  AIO O_DIRECT ops attempt to sync metadata here.
-	 */
 out:
-	if ((written >= 0 || written == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-		int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);
-		if (err < 0)
-			written = err;
-	}
 	return written;
 }
 EXPORT_SYMBOL(generic_file_direct_write);
@@ -2332,8 +2319,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
-	const struct address_space_operations *a_ops = mapping->a_ops;
-	struct inode *inode = mapping->host;
 	ssize_t status;
 	struct iov_iter i;
 
@@ -2343,16 +2328,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 	if (likely(status >= 0)) {
 		written += status;
 		*ppos = pos + status;
-
-		/*
-		 * For now, when the user asks for O_SYNC, we'll actually give
-		 * O_DSYNC
-		 */
-		if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			if (!a_ops->writepage || !is_sync_kiocb(iocb))
-				status = generic_osync_inode(inode, mapping,
-						OSYNC_METADATA|OSYNC_DATA);
-		}
   	}
 	
 	/*
@@ -2514,7 +2489,8 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range_nolock(inode, mapping, pos, ret);
@@ -2550,7 +2526,8 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range(inode, mapping, pos, ret);
-- 
1.6.0.2

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[Ocfs2-devel] [PATCH 03/17] vfs: Remove syncing from generic_file_direct_write() and generic_file_buffered_write()

[Jan Kara]

generic_file_direct_write() and generic_file_buffered_write() called
generic_osync_inode() if it was called on O_SYNC file or IS_SYNC inode. But
this is superfluous since generic_file_aio_write() does the syncing as well.
Also XFS and OCFS2 which call these functions directly handle syncing
themselves. So let's have a single place where syncing happens:
generic_file_aio_write().

We slightly change the behavior by syncing only the range of file to which the
write happened for buffered writes but that should be all that is required.

CC: ocfs2-devel at oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs at oss.sgi.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 mm/filemap.c |   31 ++++---------------------------
 1 files changed, 4 insertions(+), 27 deletions(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index 554a396..b523e42 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2187,20 +2187,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 		*ppos = end;
 	}
-
-	/*
-	 * Sync the fs metadata but not the minor inode changes and
-	 * of course not the data as we did direct DMA for the IO.
-	 * i_mutex is held, which protects generic_osync_inode() from
-	 * livelocking.  AIO O_DIRECT ops attempt to sync metadata here.
-	 */
 out:
-	if ((written >= 0 || written == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-		int err = generic_osync_inode(inode, mapping, OSYNC_METADATA);
-		if (err < 0)
-			written = err;
-	}
 	return written;
 }
 EXPORT_SYMBOL(generic_file_direct_write);
@@ -2332,8 +2319,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
-	const struct address_space_operations *a_ops = mapping->a_ops;
-	struct inode *inode = mapping->host;
 	ssize_t status;
 	struct iov_iter i;
 
@@ -2343,16 +2328,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
 	if (likely(status >= 0)) {
 		written += status;
 		*ppos = pos + status;
-
-		/*
-		 * For now, when the user asks for O_SYNC, we'll actually give
-		 * O_DSYNC
-		 */
-		if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			if (!a_ops->writepage || !is_sync_kiocb(iocb))
-				status = generic_osync_inode(inode, mapping,
-						OSYNC_METADATA|OSYNC_DATA);
-		}
   	}
 	
 	/*
@@ -2514,7 +2489,8 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range_nolock(inode, mapping, pos, ret);
@@ -2550,7 +2526,8 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if ((ret > 0 || ret == -EIOCBQUEUED) &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
 		ssize_t err;
 
 		err = sync_page_range(inode, mapping, pos, ret);
-- 
1.6.0.2

[PATCH 04/17] pohmelfs: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use new helper __generic_file_aio_write(). Since the fs takes care of syncing
by itself afterwards, there are no more changes needed.

CC: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/staging/pohmelfs/inode.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/staging/pohmelfs/inode.c b/drivers/staging/pohmelfs/inode.c
index 7b60579..17801a5 100644
--- a/drivers/staging/pohmelfs/inode.c
+++ b/drivers/staging/pohmelfs/inode.c
@@ -921,7 +921,7 @@ ssize_t pohmelfs_write(struct file *file, const char __user *buf,
 	if (ret)
 		goto err_out_unlock;
 
-	ret = generic_file_aio_write_nolock(&kiocb, &iov, 1, pos);
+	ret = __generic_file_aio_write(&kiocb, &iov, 1, &kiocb.ki_pos);
 	*ppos = kiocb.ki_pos;
 
 	mutex_unlock(&inode->i_mutex);
-- 
1.6.0.2

[PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use the new helper. We have to submit data pages ourselves in case of O_SYNC
write because __generic_file_aio_write does not do it for us. OCFS2 developpers
might think about moving the sync out of i_mutex which seems to be easily
possible but that's out of scope of this patch.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/file.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 62442e4..1c71f0a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1870,8 +1870,7 @@ relock:
 			goto out_dio;
 		}
 	} else {
-		written = generic_file_aio_write_nolock(iocb, iov, nr_segs,
-							*ppos);
+		written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
 	}
 
 out_dio:
@@ -1879,18 +1878,21 @@ out_dio:
 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
 
 	if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) {
-		/*
-		 * The generic write paths have handled getting data
-		 * to disk, but since we don't make use of the dirty
-		 * inode list, a manual journal commit is necessary
-		 * here.
-		 */
-		if (old_size != i_size_read(inode) ||
-		    old_clusters != OCFS2_I(inode)->ip_clusters) {
+		ret = filemap_fdatawrite_range(file->f_mapping, pos,
+					       pos + count - 1);
+		if (ret < 0)
+			written = ret;
+
+		if (!ret && (old_size != i_size_read(inode) ||
+		    old_clusters != OCFS2_I(inode)->ip_clusters)) {
 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
 			if (ret < 0)
 				written = ret;
 		}
+
+		if (!ret)
+			ret = filemap_fdatawait_range(file->f_mapping, pos,
+						      pos + count - 1);
 	}
 
 	/* 
-- 
1.6.0.2

[Ocfs2-devel] [PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use the new helper. We have to submit data pages ourselves in case of O_SYNC
write because __generic_file_aio_write does not do it for us. OCFS2 developpers
might think about moving the sync out of i_mutex which seems to be easily
possible but that's out of scope of this patch.

CC: ocfs2-devel at oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/file.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 62442e4..1c71f0a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1870,8 +1870,7 @@ relock:
 			goto out_dio;
 		}
 	} else {
-		written = generic_file_aio_write_nolock(iocb, iov, nr_segs,
-							*ppos);
+		written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
 	}
 
 out_dio:
@@ -1879,18 +1878,21 @@ out_dio:
 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
 
 	if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) {
-		/*
-		 * The generic write paths have handled getting data
-		 * to disk, but since we don't make use of the dirty
-		 * inode list, a manual journal commit is necessary
-		 * here.
-		 */
-		if (old_size != i_size_read(inode) ||
-		    old_clusters != OCFS2_I(inode)->ip_clusters) {
+		ret = filemap_fdatawrite_range(file->f_mapping, pos,
+					       pos + count - 1);
+		if (ret < 0)
+			written = ret;
+
+		if (!ret && (old_size != i_size_read(inode) ||
+		    old_clusters != OCFS2_I(inode)->ip_clusters)) {
 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
 			if (ret < 0)
 				written = ret;
 		}
+
+		if (!ret)
+			ret = filemap_fdatawait_range(file->f_mapping, pos,
+						      pos + count - 1);
 	}
 
 	/* 
-- 
1.6.0.2

[PATCH 06/17] vfs: Rename generic_file_aio_write_nolock

[Jan Kara]

generic_file_aio_write_nolock() is now used only by block devices and raw
character device. Filesystems should use __generic_file_aio_write() in case
generic_file_aio_write() doesn't suit them. So rename the function to
device_aio_write().

Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/char/raw.c |    2 +-
 fs/block_dev.c     |    2 +-
 include/linux/fs.h |    4 ++--
 mm/filemap.c       |    9 ++++-----
 4 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 05f9d18..c43c7a7 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -246,7 +246,7 @@ static const struct file_operations raw_fops = {
 	.read	=	do_sync_read,
 	.aio_read = 	generic_file_aio_read,
 	.write	=	do_sync_write,
-	.aio_write = 	generic_file_aio_write_nolock,
+	.aio_write =	device_aio_write,
 	.open	=	raw_open,
 	.release=	raw_release,
 	.ioctl	=	raw_ioctl,
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 94dfda2..67fc1c9 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1436,7 +1436,7 @@ const struct file_operations def_blk_fops = {
 	.read		= do_sync_read,
 	.write		= do_sync_write,
   	.aio_read	= generic_file_aio_read,
-  	.aio_write	= generic_file_aio_write_nolock,
+	.aio_write	= device_aio_write,
 	.mmap		= generic_file_mmap,
 	.fsync		= block_fsync,
 	.unlocked_ioctl	= block_ioctl,
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 1edd159..29fc8da 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2198,8 +2198,8 @@ extern ssize_t generic_file_aio_read(struct kiocb *, const struct iovec *, unsig
 extern ssize_t __generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long,
 		loff_t *);
 extern ssize_t generic_file_aio_write(struct kiocb *, const struct iovec *, unsigned long, loff_t);
-extern ssize_t generic_file_aio_write_nolock(struct kiocb *, const struct iovec *,
-		unsigned long, loff_t);
+extern ssize_t device_aio_write(struct kiocb *iocb, const struct iovec *iov,
+				unsigned long nr_segs, loff_t pos);
 extern ssize_t generic_file_direct_write(struct kiocb *, const struct iovec *,
 		unsigned long *, loff_t, loff_t *, size_t, size_t);
 extern ssize_t generic_file_buffered_write(struct kiocb *, const struct iovec *,
diff --git a/mm/filemap.c b/mm/filemap.c
index b523e42..ef9f635 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2462,9 +2462,8 @@ out:
 }
 EXPORT_SYMBOL(__generic_file_aio_write);
 
-
 /**
- * generic_file_aio_write_nolock - write data, usually to a device
+ * device_aio_write - write data
  * @iocb:	IO state structure
  * @iov:	vector with data to write
  * @nr_segs:	number of segments in the vector
@@ -2477,8 +2476,8 @@ EXPORT_SYMBOL(__generic_file_aio_write);
  * do a write but already holds i_mutex, use __generic_file_aio_write()
  * directly and then sync the file like generic_file_aio_write().
  */
-ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
-		const struct iovec *iov, unsigned long nr_segs, loff_t pos)
+ssize_t device_aio_write(struct kiocb *iocb, const struct iovec *iov,
+			 unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
@@ -2499,7 +2498,7 @@ ssize_t generic_file_aio_write_nolock(struct kiocb *iocb,
 	}
 	return ret;
 }
-EXPORT_SYMBOL(generic_file_aio_write_nolock);
+EXPORT_SYMBOL(device_aio_write);
 
 /**
  * generic_file_aio_write - write data to a file
-- 
1.6.0.2

[PATCH 07/17] vfs: Introduce new helpers for syncing after writing to O_SYNC file or IS_SYNC inode

[Jan Kara]

Introduce new function for generic inode syncing (generic_sync_file) and use
it from fsync() path. Introduce also new helper for syncing after a sync
write (generic_write_sync) using the generic function.

Use these new helpers for syncing from generic VFS functions. This makes
O_SYNC writes to block devices acquire i_mutex for syncing. If we really
care about this, we can make block_fsync() drop the i_mutex and reacquire
it before it returns.

CC: Evgeniy Polyakov <zbr@ioremap.net>
CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
CC: Anton Altaparmakov <aia21@cantab.net>
CC: linux-ntfs-dev@lists.sourceforge.net
CC: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
CC: linux-ext4@vger.kernel.org
CC: tytso@mit.edu
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/splice.c        |   22 ++++----------
 fs/sync.c          |   81 +++++++++++++++++++++++++++++++++++++++++++---------
 include/linux/fs.h |    7 ++++
 mm/filemap.c       |   18 ++++--------
 4 files changed, 86 insertions(+), 42 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index 73766d2..8190237 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -976,25 +976,15 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
 
 	if (ret > 0) {
 		unsigned long nr_pages;
+		int err;
 
-		*ppos += ret;
 		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 
-		/*
-		 * If file or inode is SYNC and we actually wrote some data,
-		 * sync it.
-		 */
-		if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			int err;
-
-			mutex_lock(&inode->i_mutex);
-			err = generic_osync_inode(inode, mapping,
-						  OSYNC_METADATA|OSYNC_DATA);
-			mutex_unlock(&inode->i_mutex);
-
-			if (err)
-				ret = err;
-		}
+		err = generic_write_sync(out, *ppos, ret);
+		if (err)
+			ret = err;
+		else
+			*ppos += ret;
 		balance_dirty_pages_ratelimited_nr(mapping, nr_pages);
 	}
 
diff --git a/fs/sync.c b/fs/sync.c
index 3422ba6..fc320aa 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -176,23 +176,30 @@ int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
 }
 
 /**
- * vfs_fsync - perform a fsync or fdatasync on a file
+ * generic_sync_file - helper to sync data & metadata to disk
  * @file:		file to sync
  * @dentry:		dentry of @file
- * @data:		only perform a fdatasync operation
+ * @start:		offset in bytes of the beginning of data range to sync
+ * @end:		offset in bytes of the end of data range (inclusive)
+ * @what:		what should be synced
  *
- * Write back data and metadata for @file to disk.  If @datasync is
- * set only metadata needed to access modified file data is written.
+ * What the function exactly does is controlled by the @what parameter:
  *
- * In case this function is called from nfsd @file may be %NULL and
- * only @dentry is set.  This can only happen when the filesystem
- * implements the export_operations API.
+ * If SYNC_SUBMIT_DATA is set, the function submits all pages in the given
+ * range to disk.
+ *
+ * The function always calls ->fsync() callback of the filesystem. If
+ * SYNC_INODE is not set, we pass down the fact that it is just a datasync.
+ *
+ * If SYNC_WAIT_DATA is set, the function waits for writeback to finish
+ * in the given range.
  */
-int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+int generic_sync_file(struct file *file, struct dentry *dentry, loff_t start,
+		      loff_t end, int what)
 {
 	const struct file_operations *fop;
 	struct address_space *mapping;
-	int err, ret;
+	int err, ret = 0;
 
 	/*
 	 * Get mapping and operations from the file in case we have
@@ -212,23 +219,50 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 		goto out;
 	}
 
-	ret = filemap_fdatawrite(mapping);
+	if (what & SYNC_SUBMIT_DATA)
+		ret = filemap_fdatawrite_range(mapping, start, end);
 
 	/*
 	 * We need to protect against concurrent writers, which could cause
 	 * livelocks in fsync_buffers_list().
 	 */
 	mutex_lock(&mapping->host->i_mutex);
-	err = fop->fsync(file, dentry, datasync);
+	err = fop->fsync(file, dentry, !(what & SYNC_INODE));
 	if (!ret)
 		ret = err;
 	mutex_unlock(&mapping->host->i_mutex);
-	err = filemap_fdatawait(mapping);
-	if (!ret)
-		ret = err;
+
+	if (what & SYNC_WAIT_DATA) {
+		err = filemap_fdatawait_range(mapping, start, end);
+		if (!ret)
+			ret = err;
+	}
 out:
 	return ret;
 }
+EXPORT_SYMBOL(generic_sync_file);
+
+/**
+ * vfs_fsync - perform a fsync or fdatasync on a file
+ * @file:		file to sync
+ * @dentry:		dentry of @file
+ * @datasync:		only perform a fdatasync operation
+ *
+ * Write back data and metadata for @file to disk.  If @datasync is
+ * set only metadata needed to access modified file data is written.
+ *
+ * In case this function is called from nfsd @file may be %NULL and
+ * only @dentry is set.  This can only happen when the filesystem
+ * implements the export_operations API.
+ */
+int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+	int what = SYNC_SUBMIT_DATA | SYNC_WAIT_DATA;
+
+	if (!datasync)
+		what |= SYNC_INODE;
+	return generic_sync_file(file, dentry, 0, LLONG_MAX, what);
+}
 EXPORT_SYMBOL(vfs_fsync);
 
 static int do_fsync(unsigned int fd, int datasync)
@@ -254,6 +288,25 @@ SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
 	return do_fsync(fd, 1);
 }
 
+/**
+ * generic_write_sync - perform syncing after a write if file / inode is sync
+ * @file:	file to which the write happened
+ * @pos:	offset where the write started
+ * @count:	length of the write
+ *
+ * This is just a simple wrapper about our general syncing function.
+ * FIXME: Make it inline?
+ */
+int generic_write_sync(struct file *file, loff_t pos, loff_t count)
+{
+	if (!(file->f_flags & O_SYNC) && !IS_SYNC(file->f_mapping->host))
+		return 0;
+	return generic_sync_file(file, file->f_path.dentry, pos,
+				 pos + count - 1,
+				 SYNC_SUBMIT_DATA | SYNC_WAIT_DATA);
+}
+EXPORT_SYMBOL(generic_write_sync);
+
 /*
  * sys_sync_file_range() permits finely controlled syncing over a segment of
  * a file in the range offset .. (offset+nbytes-1) inclusive.  If nbytes is
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 29fc8da..648001c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2088,7 +2088,14 @@ extern int __filemap_fdatawrite_range(struct address_space *mapping,
 extern int filemap_fdatawrite_range(struct address_space *mapping,
 				loff_t start, loff_t end);
 
+/* Flags for generic_sync_file */
+#define SYNC_INODE		1
+#define SYNC_SUBMIT_DATA	2
+#define SYNC_WAIT_DATA		4
+extern int generic_sync_file(struct file *file, struct dentry *dentry,
+			   loff_t start, loff_t end, int what);
 extern int vfs_fsync(struct file *file, struct dentry *dentry, int datasync);
+extern int generic_write_sync(struct file *file, loff_t pos, loff_t count);
 extern void sync_supers(void);
 extern void emergency_sync(void);
 extern void emergency_remount(void);
diff --git a/mm/filemap.c b/mm/filemap.c
index ef9f635..d0802a9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -39,11 +39,10 @@
 /*
  * FIXME: remove all knowledge of the buffer layer from the core VM
  */
-#include <linux/buffer_head.h> /* for generic_osync_inode */
+#include <linux/buffer_head.h> /* for try_to_free_buffers */
 
 #include <asm/mman.h>
 
-
 /*
  * Shared mappings implemented 30.11.1994. It's not fully working yet,
  * though.
@@ -2480,19 +2479,16 @@ ssize_t device_aio_write(struct kiocb *iocb, const struct iovec *iov,
 			 unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range_nolock(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
@@ -2515,8 +2511,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
+	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
@@ -2525,11 +2520,10 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
-- 
1.6.0.2

[PATCH 07/17] vfs: Introduce new helpers for syncing after writing to O_SYNC file or IS_SYNC inode

[Jan Kara]

Introduce new function for generic inode syncing (generic_sync_file) and use
it from fsync() path. Introduce also new helper for syncing after a sync
write (generic_write_sync) using the generic function.

Use these new helpers for syncing from generic VFS functions. This makes
O_SYNC writes to block devices acquire i_mutex for syncing. If we really
care about this, we can make block_fsync() drop the i_mutex and reacquire
it before it returns.

CC: Evgeniy Polyakov <zbr@ioremap.net>
CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs@oss.sgi.com
CC: Anton Altaparmakov <aia21@cantab.net>
CC: linux-ntfs-dev@lists.sourceforge.net
CC: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
CC: linux-ext4@vger.kernel.org
CC: tytso@mit.edu
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/splice.c        |   22 ++++----------
 fs/sync.c          |   81 +++++++++++++++++++++++++++++++++++++++++++---------
 include/linux/fs.h |    7 ++++
 mm/filemap.c       |   18 ++++--------
 4 files changed, 86 insertions(+), 42 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index 73766d2..8190237 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -976,25 +976,15 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
 
 	if (ret > 0) {
 		unsigned long nr_pages;
+		int err;
 
-		*ppos += ret;
 		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 
-		/*
-		 * If file or inode is SYNC and we actually wrote some data,
-		 * sync it.
-		 */
-		if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			int err;
-
-			mutex_lock(&inode->i_mutex);
-			err = generic_osync_inode(inode, mapping,
-						  OSYNC_METADATA|OSYNC_DATA);
-			mutex_unlock(&inode->i_mutex);
-
-			if (err)
-				ret = err;
-		}
+		err = generic_write_sync(out, *ppos, ret);
+		if (err)
+			ret = err;
+		else
+			*ppos += ret;
 		balance_dirty_pages_ratelimited_nr(mapping, nr_pages);
 	}
 
diff --git a/fs/sync.c b/fs/sync.c
index 3422ba6..fc320aa 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -176,23 +176,30 @@ int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
 }
 
 /**
- * vfs_fsync - perform a fsync or fdatasync on a file
+ * generic_sync_file - helper to sync data & metadata to disk
  * @file:		file to sync
  * @dentry:		dentry of @file
- * @data:		only perform a fdatasync operation
+ * @start:		offset in bytes of the beginning of data range to sync
+ * @end:		offset in bytes of the end of data range (inclusive)
+ * @what:		what should be synced
  *
- * Write back data and metadata for @file to disk.  If @datasync is
- * set only metadata needed to access modified file data is written.
+ * What the function exactly does is controlled by the @what parameter:
  *
- * In case this function is called from nfsd @file may be %NULL and
- * only @dentry is set.  This can only happen when the filesystem
- * implements the export_operations API.
+ * If SYNC_SUBMIT_DATA is set, the function submits all pages in the given
+ * range to disk.
+ *
+ * The function always calls ->fsync() callback of the filesystem. If
+ * SYNC_INODE is not set, we pass down the fact that it is just a datasync.
+ *
+ * If SYNC_WAIT_DATA is set, the function waits for writeback to finish
+ * in the given range.
  */
-int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+int generic_sync_file(struct file *file, struct dentry *dentry, loff_t start,
+		      loff_t end, int what)
 {
 	const struct file_operations *fop;
 	struct address_space *mapping;
-	int err, ret;
+	int err, ret = 0;
 
 	/*
 	 * Get mapping and operations from the file in case we have
@@ -212,23 +219,50 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 		goto out;
 	}
 
-	ret = filemap_fdatawrite(mapping);
+	if (what & SYNC_SUBMIT_DATA)
+		ret = filemap_fdatawrite_range(mapping, start, end);
 
 	/*
 	 * We need to protect against concurrent writers, which could cause
 	 * livelocks in fsync_buffers_list().
 	 */
 	mutex_lock(&mapping->host->i_mutex);
-	err = fop->fsync(file, dentry, datasync);
+	err = fop->fsync(file, dentry, !(what & SYNC_INODE));
 	if (!ret)
 		ret = err;
 	mutex_unlock(&mapping->host->i_mutex);
-	err = filemap_fdatawait(mapping);
-	if (!ret)
-		ret = err;
+
+	if (what & SYNC_WAIT_DATA) {
+		err = filemap_fdatawait_range(mapping, start, end);
+		if (!ret)
+			ret = err;
+	}
 out:
 	return ret;
 }
+EXPORT_SYMBOL(generic_sync_file);
+
+/**
+ * vfs_fsync - perform a fsync or fdatasync on a file
+ * @file:		file to sync
+ * @dentry:		dentry of @file
+ * @datasync:		only perform a fdatasync operation
+ *
+ * Write back data and metadata for @file to disk.  If @datasync is
+ * set only metadata needed to access modified file data is written.
+ *
+ * In case this function is called from nfsd @file may be %NULL and
+ * only @dentry is set.  This can only happen when the filesystem
+ * implements the export_operations API.
+ */
+int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+	int what = SYNC_SUBMIT_DATA | SYNC_WAIT_DATA;
+
+	if (!datasync)
+		what |= SYNC_INODE;
+	return generic_sync_file(file, dentry, 0, LLONG_MAX, what);
+}
 EXPORT_SYMBOL(vfs_fsync);
 
 static int do_fsync(unsigned int fd, int datasync)
@@ -254,6 +288,25 @@ SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
 	return do_fsync(fd, 1);
 }
 
+/**
+ * generic_write_sync - perform syncing after a write if file / inode is sync
+ * @file:	file to which the write happened
+ * @pos:	offset where the write started
+ * @count:	length of the write
+ *
+ * This is just a simple wrapper about our general syncing function.
+ * FIXME: Make it inline?
+ */
+int generic_write_sync(struct file *file, loff_t pos, loff_t count)
+{
+	if (!(file->f_flags & O_SYNC) && !IS_SYNC(file->f_mapping->host))
+		return 0;
+	return generic_sync_file(file, file->f_path.dentry, pos,
+				 pos + count - 1,
+				 SYNC_SUBMIT_DATA | SYNC_WAIT_DATA);
+}
+EXPORT_SYMBOL(generic_write_sync);
+
 /*
  * sys_sync_file_range() permits finely controlled syncing over a segment of
  * a file in the range offset .. (offset+nbytes-1) inclusive.  If nbytes is
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 29fc8da..648001c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2088,7 +2088,14 @@ extern int __filemap_fdatawrite_range(struct address_space *mapping,
 extern int filemap_fdatawrite_range(struct address_space *mapping,
 				loff_t start, loff_t end);
 
+/* Flags for generic_sync_file */
+#define SYNC_INODE		1
+#define SYNC_SUBMIT_DATA	2
+#define SYNC_WAIT_DATA		4
+extern int generic_sync_file(struct file *file, struct dentry *dentry,
+			   loff_t start, loff_t end, int what);
 extern int vfs_fsync(struct file *file, struct dentry *dentry, int datasync);
+extern int generic_write_sync(struct file *file, loff_t pos, loff_t count);
 extern void sync_supers(void);
 extern void emergency_sync(void);
 extern void emergency_remount(void);
diff --git a/mm/filemap.c b/mm/filemap.c
index ef9f635..d0802a9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -39,11 +39,10 @@
 /*
  * FIXME: remove all knowledge of the buffer layer from the core VM
  */
-#include <linux/buffer_head.h> /* for generic_osync_inode */
+#include <linux/buffer_head.h> /* for try_to_free_buffers */
 
 #include <asm/mman.h>
 
-
 /*
  * Shared mappings implemented 30.11.1994. It's not fully working yet,
  * though.
@@ -2480,19 +2479,16 @@ ssize_t device_aio_write(struct kiocb *iocb, const struct iovec *iov,
 			 unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range_nolock(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
@@ -2515,8 +2511,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
+	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
@@ -2525,11 +2520,10 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
-- 
1.6.0.2

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs

[PATCH 08/17] ext2: Update comment about generic_osync_inode

[Jan Kara]

We rely on generic_write_sync() now.

CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ext2/inode.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index e271303..1c1638f 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -482,7 +482,7 @@ static int ext2_alloc_branch(struct inode *inode,
 		unlock_buffer(bh);
 		mark_buffer_dirty_inode(bh, inode);
 		/* We used to sync bh here if IS_SYNC(inode).
-		 * But we now rely upon generic_osync_inode()
+		 * But we now rely upon generic_write_sync()
 		 * and b_inode_buffers.  But not for directories.
 		 */
 		if (S_ISDIR(inode->i_mode) && IS_DIRSYNC(inode))
-- 
1.6.0.2

[PATCH 09/17] ext3: Remove syncing logic from ext3_file_write

[Jan Kara]

Syncing is now properly done by generic_file_aio_write() so no special logic is
needed in ext3.

CC: linux-ext4@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ext3/file.c |   61 +-------------------------------------------------------
 1 files changed, 1 insertions(+), 60 deletions(-)

diff --git a/fs/ext3/file.c b/fs/ext3/file.c
index 5b49704..51fee5f 100644
--- a/fs/ext3/file.c
+++ b/fs/ext3/file.c
@@ -51,71 +51,12 @@ static int ext3_release_file (struct inode * inode, struct file * filp)
 	return 0;
 }
 
-static ssize_t
-ext3_file_write(struct kiocb *iocb, const struct iovec *iov,
-		unsigned long nr_segs, loff_t pos)
-{
-	struct file *file = iocb->ki_filp;
-	struct inode *inode = file->f_path.dentry->d_inode;
-	ssize_t ret;
-	int err;
-
-	ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
-
-	/*
-	 * Skip flushing if there was an error, or if nothing was written.
-	 */
-	if (ret <= 0)
-		return ret;
-
-	/*
-	 * If the inode is IS_SYNC, or is O_SYNC and we are doing data
-	 * journalling then we need to make sure that we force the transaction
-	 * to disk to keep all metadata uptodate synchronously.
-	 */
-	if (file->f_flags & O_SYNC) {
-		/*
-		 * If we are non-data-journaled, then the dirty data has
-		 * already been flushed to backing store by generic_osync_inode,
-		 * and the inode has been flushed too if there have been any
-		 * modifications other than mere timestamp updates.
-		 *
-		 * Open question --- do we care about flushing timestamps too
-		 * if the inode is IS_SYNC?
-		 */
-		if (!ext3_should_journal_data(inode))
-			return ret;
-
-		goto force_commit;
-	}
-
-	/*
-	 * So we know that there has been no forced data flush.  If the inode
-	 * is marked IS_SYNC, we need to force one ourselves.
-	 */
-	if (!IS_SYNC(inode))
-		return ret;
-
-	/*
-	 * Open question #2 --- should we force data to disk here too?  If we
-	 * don't, the only impact is that data=writeback filesystems won't
-	 * flush data to disk automatically on IS_SYNC, only metadata (but
-	 * historically, that is what ext2 has done.)
-	 */
-
-force_commit:
-	err = ext3_force_commit(inode->i_sb);
-	if (err)
-		return err;
-	return ret;
-}
-
 const struct file_operations ext3_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
 	.write		= do_sync_write,
 	.aio_read	= generic_file_aio_read,
-	.aio_write	= ext3_file_write,
+	.aio_write	= generic_file_aio_write,
 	.unlocked_ioctl	= ext3_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= ext3_compat_ioctl,
-- 
1.6.0.2

[PATCH 10/17] ext4: Remove syncing logic from ext4_file_write

[Jan Kara]

The syncing is now properly handled by generic_file_aio_write() so
no special ext4 code is needed.

CC: linux-ext4@vger.kernel.org
CC: tytso@mit.edu
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/file.c |   53 ++---------------------------------------------------
 1 files changed, 2 insertions(+), 51 deletions(-)

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 3f1873f..aafe432 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -58,10 +58,7 @@ static ssize_t
 ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
-	struct file *file = iocb->ki_filp;
-	struct inode *inode = file->f_path.dentry->d_inode;
-	ssize_t ret;
-	int err;
+	struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
 
 	/*
 	 * If we have encountered a bitmap-format file, the size limit
@@ -81,53 +78,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 		}
 	}
 
-	ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
-	/*
-	 * Skip flushing if there was an error, or if nothing was written.
-	 */
-	if (ret <= 0)
-		return ret;
-
-	/*
-	 * If the inode is IS_SYNC, or is O_SYNC and we are doing data
-	 * journalling then we need to make sure that we force the transaction
-	 * to disk to keep all metadata uptodate synchronously.
-	 */
-	if (file->f_flags & O_SYNC) {
-		/*
-		 * If we are non-data-journaled, then the dirty data has
-		 * already been flushed to backing store by generic_osync_inode,
-		 * and the inode has been flushed too if there have been any
-		 * modifications other than mere timestamp updates.
-		 *
-		 * Open question --- do we care about flushing timestamps too
-		 * if the inode is IS_SYNC?
-		 */
-		if (!ext4_should_journal_data(inode))
-			return ret;
-
-		goto force_commit;
-	}
-
-	/*
-	 * So we know that there has been no forced data flush.  If the inode
-	 * is marked IS_SYNC, we need to force one ourselves.
-	 */
-	if (!IS_SYNC(inode))
-		return ret;
-
-	/*
-	 * Open question #2 --- should we force data to disk here too?  If we
-	 * don't, the only impact is that data=writeback filesystems won't
-	 * flush data to disk automatically on IS_SYNC, only metadata (but
-	 * historically, that is what ext2 has done.)
-	 */
-
-force_commit:
-	err = ext4_force_commit(inode->i_sb);
-	if (err)
-		return err;
-	return ret;
+	return generic_file_aio_write(iocb, iov, nr_segs, pos);
 }
 
 static struct vm_operations_struct ext4_file_vm_ops = {
-- 
1.6.0.2

[Ocfs2-devel] [PATCH 07/17] vfs: Introduce new helpers for syncing after writing to O_SYNC file or IS_SYNC inode

[Jan Kara]

Introduce new function for generic inode syncing (generic_sync_file) and use
it from fsync() path. Introduce also new helper for syncing after a sync
write (generic_write_sync) using the generic function.

Use these new helpers for syncing from generic VFS functions. This makes
O_SYNC writes to block devices acquire i_mutex for syncing. If we really
care about this, we can make block_fsync() drop the i_mutex and reacquire
it before it returns.

CC: Evgeniy Polyakov <zbr@ioremap.net>
CC: ocfs2-devel at oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
CC: Felix Blyakher <felixb@sgi.com>
CC: xfs at oss.sgi.com
CC: Anton Altaparmakov <aia21@cantab.net>
CC: linux-ntfs-dev at lists.sourceforge.net
CC: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
CC: linux-ext4 at vger.kernel.org
CC: tytso at mit.edu
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/splice.c        |   22 ++++----------
 fs/sync.c          |   81 +++++++++++++++++++++++++++++++++++++++++++---------
 include/linux/fs.h |    7 ++++
 mm/filemap.c       |   18 ++++--------
 4 files changed, 86 insertions(+), 42 deletions(-)

diff --git a/fs/splice.c b/fs/splice.c
index 73766d2..8190237 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -976,25 +976,15 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
 
 	if (ret > 0) {
 		unsigned long nr_pages;
+		int err;
 
-		*ppos += ret;
 		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 
-		/*
-		 * If file or inode is SYNC and we actually wrote some data,
-		 * sync it.
-		 */
-		if (unlikely((out->f_flags & O_SYNC) || IS_SYNC(inode))) {
-			int err;
-
-			mutex_lock(&inode->i_mutex);
-			err = generic_osync_inode(inode, mapping,
-						  OSYNC_METADATA|OSYNC_DATA);
-			mutex_unlock(&inode->i_mutex);
-
-			if (err)
-				ret = err;
-		}
+		err = generic_write_sync(out, *ppos, ret);
+		if (err)
+			ret = err;
+		else
+			*ppos += ret;
 		balance_dirty_pages_ratelimited_nr(mapping, nr_pages);
 	}
 
diff --git a/fs/sync.c b/fs/sync.c
index 3422ba6..fc320aa 100644
--- a/fs/sync.c
+++ b/fs/sync.c
@@ -176,23 +176,30 @@ int file_fsync(struct file *filp, struct dentry *dentry, int datasync)
 }
 
 /**
- * vfs_fsync - perform a fsync or fdatasync on a file
+ * generic_sync_file - helper to sync data & metadata to disk
  * @file:		file to sync
  * @dentry:		dentry of @file
- * @data:		only perform a fdatasync operation
+ * @start:		offset in bytes of the beginning of data range to sync
+ * @end:		offset in bytes of the end of data range (inclusive)
+ * @what:		what should be synced
  *
- * Write back data and metadata for @file to disk.  If @datasync is
- * set only metadata needed to access modified file data is written.
+ * What the function exactly does is controlled by the @what parameter:
  *
- * In case this function is called from nfsd @file may be %NULL and
- * only @dentry is set.  This can only happen when the filesystem
- * implements the export_operations API.
+ * If SYNC_SUBMIT_DATA is set, the function submits all pages in the given
+ * range to disk.
+ *
+ * The function always calls ->fsync() callback of the filesystem. If
+ * SYNC_INODE is not set, we pass down the fact that it is just a datasync.
+ *
+ * If SYNC_WAIT_DATA is set, the function waits for writeback to finish
+ * in the given range.
  */
-int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+int generic_sync_file(struct file *file, struct dentry *dentry, loff_t start,
+		      loff_t end, int what)
 {
 	const struct file_operations *fop;
 	struct address_space *mapping;
-	int err, ret;
+	int err, ret = 0;
 
 	/*
 	 * Get mapping and operations from the file in case we have
@@ -212,23 +219,50 @@ int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 		goto out;
 	}
 
-	ret = filemap_fdatawrite(mapping);
+	if (what & SYNC_SUBMIT_DATA)
+		ret = filemap_fdatawrite_range(mapping, start, end);
 
 	/*
 	 * We need to protect against concurrent writers, which could cause
 	 * livelocks in fsync_buffers_list().
 	 */
 	mutex_lock(&mapping->host->i_mutex);
-	err = fop->fsync(file, dentry, datasync);
+	err = fop->fsync(file, dentry, !(what & SYNC_INODE));
 	if (!ret)
 		ret = err;
 	mutex_unlock(&mapping->host->i_mutex);
-	err = filemap_fdatawait(mapping);
-	if (!ret)
-		ret = err;
+
+	if (what & SYNC_WAIT_DATA) {
+		err = filemap_fdatawait_range(mapping, start, end);
+		if (!ret)
+			ret = err;
+	}
 out:
 	return ret;
 }
+EXPORT_SYMBOL(generic_sync_file);
+
+/**
+ * vfs_fsync - perform a fsync or fdatasync on a file
+ * @file:		file to sync
+ * @dentry:		dentry of @file
+ * @datasync:		only perform a fdatasync operation
+ *
+ * Write back data and metadata for @file to disk.  If @datasync is
+ * set only metadata needed to access modified file data is written.
+ *
+ * In case this function is called from nfsd @file may be %NULL and
+ * only @dentry is set.  This can only happen when the filesystem
+ * implements the export_operations API.
+ */
+int vfs_fsync(struct file *file, struct dentry *dentry, int datasync)
+{
+	int what = SYNC_SUBMIT_DATA | SYNC_WAIT_DATA;
+
+	if (!datasync)
+		what |= SYNC_INODE;
+	return generic_sync_file(file, dentry, 0, LLONG_MAX, what);
+}
 EXPORT_SYMBOL(vfs_fsync);
 
 static int do_fsync(unsigned int fd, int datasync)
@@ -254,6 +288,25 @@ SYSCALL_DEFINE1(fdatasync, unsigned int, fd)
 	return do_fsync(fd, 1);
 }
 
+/**
+ * generic_write_sync - perform syncing after a write if file / inode is sync
+ * @file:	file to which the write happened
+ * @pos:	offset where the write started
+ * @count:	length of the write
+ *
+ * This is just a simple wrapper about our general syncing function.
+ * FIXME: Make it inline?
+ */
+int generic_write_sync(struct file *file, loff_t pos, loff_t count)
+{
+	if (!(file->f_flags & O_SYNC) && !IS_SYNC(file->f_mapping->host))
+		return 0;
+	return generic_sync_file(file, file->f_path.dentry, pos,
+				 pos + count - 1,
+				 SYNC_SUBMIT_DATA | SYNC_WAIT_DATA);
+}
+EXPORT_SYMBOL(generic_write_sync);
+
 /*
  * sys_sync_file_range() permits finely controlled syncing over a segment of
  * a file in the range offset .. (offset+nbytes-1) inclusive.  If nbytes is
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 29fc8da..648001c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2088,7 +2088,14 @@ extern int __filemap_fdatawrite_range(struct address_space *mapping,
 extern int filemap_fdatawrite_range(struct address_space *mapping,
 				loff_t start, loff_t end);
 
+/* Flags for generic_sync_file */
+#define SYNC_INODE		1
+#define SYNC_SUBMIT_DATA	2
+#define SYNC_WAIT_DATA		4
+extern int generic_sync_file(struct file *file, struct dentry *dentry,
+			   loff_t start, loff_t end, int what);
 extern int vfs_fsync(struct file *file, struct dentry *dentry, int datasync);
+extern int generic_write_sync(struct file *file, loff_t pos, loff_t count);
 extern void sync_supers(void);
 extern void emergency_sync(void);
 extern void emergency_remount(void);
diff --git a/mm/filemap.c b/mm/filemap.c
index ef9f635..d0802a9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -39,11 +39,10 @@
 /*
  * FIXME: remove all knowledge of the buffer layer from the core VM
  */
-#include <linux/buffer_head.h> /* for generic_osync_inode */
+#include <linux/buffer_head.h> /* for try_to_free_buffers */
 
 #include <asm/mman.h>
 
-
 /*
  * Shared mappings implemented 30.11.1994. It's not fully working yet,
  * though.
@@ -2480,19 +2479,16 @@ ssize_t device_aio_write(struct kiocb *iocb, const struct iovec *iov,
 			 unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range_nolock(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
@@ -2515,8 +2511,7 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 		unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
+	struct inode *inode = file->f_mapping->host;
 	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
@@ -2525,11 +2520,10 @@ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos);
 	mutex_unlock(&inode->i_mutex);
 
-	if ((ret > 0 || ret == -EIOCBQUEUED) &&
-	    ((file->f_flags & O_SYNC) || IS_SYNC(inode))) {
+	if (ret > 0 || ret == -EIOCBQUEUED) {
 		ssize_t err;
 
-		err = sync_page_range(inode, mapping, pos, ret);
+		err = generic_write_sync(file, pos, ret);
 		if (err < 0)
 			ret = err;
 	}
-- 
1.6.0.2

Re: [PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Joel Becker]

On Fri, Aug 21, 2009 at 07:23:55PM +0200, Jan Kara wrote:
> Use the new helper. We have to submit data pages ourselves in case of O_SYNC
> write because __generic_file_aio_write does not do it for us. OCFS2 developpers
> might think about moving the sync out of i_mutex which seems to be easily
> possible but that's out of scope of this patch.
> 
> CC: ocfs2-devel@oss.oracle.com
> CC: Joel Becker <joel.becker@oracle.com>
> Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Joel Becker <joel.becker@oracle.com>
 

-- 

"The real reason GNU ls is 8-bit-clean is so that they can
 start using ISO-8859-1 option characters."
	- Christopher Davis (ckd@loiosh.kei.com)

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127

Re: [PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Joel Becker]

On Fri, Aug 21, 2009 at 07:23:55PM +0200, Jan Kara wrote:
> Use the new helper. We have to submit data pages ourselves in case of O_SYNC
> write because __generic_file_aio_write does not do it for us. OCFS2 developpers
> might think about moving the sync out of i_mutex which seems to be easily
> possible but that's out of scope of this patch.
> 
> CC: ocfs2-devel@oss.oracle.com
> CC: Joel Becker <joel.becker@oracle.com>
> Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Joel Becker <joel.becker@oracle.com>
 

-- 

"The real reason GNU ls is 8-bit-clean is so that they can
 start using ISO-8859-1 option characters."
	- Christopher Davis (ckd@loiosh.kei.com)

Joel Becker
Principal Software Developer
Oracle
E-mail: joel.becker@oracle.com
Phone: (650) 506-8127

[PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use the new helper. We have to submit data pages ourselves in case of O_SYNC
write because __generic_file_aio_write does not do it for us. OCFS2 developpers
might think about moving the sync out of i_mutex which seems to be easily
possible but that's out of scope of this patch.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/file.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 62442e4..1c71f0a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1870,8 +1870,7 @@ relock:
 			goto out_dio;
 		}
 	} else {
-		written = generic_file_aio_write_nolock(iocb, iov, nr_segs,
-							*ppos);
+		written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
 	}
 
 out_dio:
@@ -1879,18 +1878,21 @@ out_dio:
 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
 
 	if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) {
-		/*
-		 * The generic write paths have handled getting data
-		 * to disk, but since we don't make use of the dirty
-		 * inode list, a manual journal commit is necessary
-		 * here.
-		 */
-		if (old_size != i_size_read(inode) ||
-		    old_clusters != OCFS2_I(inode)->ip_clusters) {
+		ret = filemap_fdatawrite_range(file->f_mapping, pos,
+					       pos + count - 1);
+		if (ret < 0)
+			written = ret;
+
+		if (!ret && (old_size != i_size_read(inode) ||
+		    old_clusters != OCFS2_I(inode)->ip_clusters)) {
 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
 			if (ret < 0)
 				written = ret;
 		}
+
+		if (!ret)
+			ret = filemap_fdatawait_range(file->f_mapping, pos,
+						      pos + count - 1);
 	}
 
 	/* 
-- 
1.6.0.2

[PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use the new helper. We have to submit data pages ourselves in case of O_SYNC
write because __generic_file_aio_write does not do it for us. OCFS2 developpers
might think about moving the sync out of i_mutex which seems to be easily
possible but that's out of scope of this patch.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/file.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 62442e4..1c71f0a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1870,8 +1870,7 @@ relock:
 			goto out_dio;
 		}
 	} else {
-		written = generic_file_aio_write_nolock(iocb, iov, nr_segs,
-							*ppos);
+		written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
 	}
 
 out_dio:
@@ -1879,18 +1878,21 @@ out_dio:
 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
 
 	if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) {
-		/*
-		 * The generic write paths have handled getting data
-		 * to disk, but since we don't make use of the dirty
-		 * inode list, a manual journal commit is necessary
-		 * here.
-		 */
-		if (old_size != i_size_read(inode) ||
-		    old_clusters != OCFS2_I(inode)->ip_clusters) {
+		ret = filemap_fdatawrite_range(file->f_mapping, pos,
+					       pos + count - 1);
+		if (ret < 0)
+			written = ret;
+
+		if (!ret && (old_size != i_size_read(inode) ||
+		    old_clusters != OCFS2_I(inode)->ip_clusters)) {
 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
 			if (ret < 0)
 				written = ret;
 		}
+
+		if (!ret)
+			ret = filemap_fdatawait_range(file->f_mapping, pos,
+						      pos + count - 1);
 	}
 
 	/* 
-- 
1.6.0.2

[PATCH 05/17] ocfs2: Use __generic_file_aio_write instead of generic_file_aio_write_nolock

[Jan Kara]

Use the new helper. We have to submit data pages ourselves in case of O_SYNC
write because __generic_file_aio_write does not do it for us. OCFS2 developpers
might think about moving the sync out of i_mutex which seems to be easily
possible but that's out of scope of this patch.

CC: ocfs2-devel@oss.oracle.com
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/file.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 62442e4..1c71f0a 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1870,8 +1870,7 @@ relock:
 			goto out_dio;
 		}
 	} else {
-		written = generic_file_aio_write_nolock(iocb, iov, nr_segs,
-							*ppos);
+		written = __generic_file_aio_write(iocb, iov, nr_segs, ppos);
 	}
 
 out_dio:
@@ -1879,18 +1878,21 @@ out_dio:
 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
 
 	if ((file->f_flags & O_SYNC && !direct_io) || IS_SYNC(inode)) {
-		/*
-		 * The generic write paths have handled getting data
-		 * to disk, but since we don't make use of the dirty
-		 * inode list, a manual journal commit is necessary
-		 * here.
-		 */
-		if (old_size != i_size_read(inode) ||
-		    old_clusters != OCFS2_I(inode)->ip_clusters) {
+		ret = filemap_fdatawrite_range(file->f_mapping, pos,
+					       pos + count - 1);
+		if (ret < 0)
+			written = ret;
+
+		if (!ret && (old_size != i_size_read(inode) ||
+		    old_clusters != OCFS2_I(inode)->ip_clusters)) {
 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
 			if (ret < 0)
 				written = ret;
 		}
+
+		if (!ret)
+			ret = filemap_fdatawait_range(file->f_mapping, pos,
+						      pos + count - 1);
 	}
 
 	/* 
-- 
1.6.0.2