[1/1] fs: Use inode_lock/unlock class of provided APIs in filesystems
diff mbox series

Message ID 20191205103902.23618-2-riteshh@linux.ibm.com
State New
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Series
  • Use inode_lock/unlock class of provided APIs in filesystems
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Commit Message

Ritesh Harjani Dec. 5, 2019, 10:39 a.m. UTC
This defines 4 more APIs which some of the filesystem needs
and reduces the direct use of i_rwsem in filesystem drivers.
Instead those are replaced with inode_lock/unlock_** APIs.

Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
---
 fs/btrfs/delayed-inode.c |  2 +-
 fs/btrfs/ioctl.c         |  4 ++--
 fs/ceph/io.c             | 24 ++++++++++++------------
 fs/nfs/io.c              | 24 ++++++++++++------------
 fs/orangefs/file.c       |  4 ++--
 fs/overlayfs/readdir.c   |  2 +-
 fs/readdir.c             |  4 ++--
 include/linux/fs.h       | 21 +++++++++++++++++++++
 8 files changed, 53 insertions(+), 32 deletions(-)

Comments

Matthew Wilcox Dec. 5, 2019, 1:38 p.m. UTC | #1
On Thu, Dec 05, 2019 at 04:09:02PM +0530, Ritesh Harjani wrote:
> This defines 4 more APIs which some of the filesystem needs
> and reduces the direct use of i_rwsem in filesystem drivers.
> Instead those are replaced with inode_lock/unlock_** APIs.
> 
> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>

Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
David Sterba Dec. 5, 2019, 1:42 p.m. UTC | #2
On Thu, Dec 05, 2019 at 04:09:02PM +0530, Ritesh Harjani wrote:
> This defines 4 more APIs which some of the filesystem needs
> and reduces the direct use of i_rwsem in filesystem drivers.
> Instead those are replaced with inode_lock/unlock_** APIs.
> 
> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
> ---

For the btrfs part

>  fs/btrfs/delayed-inode.c |  2 +-
>  fs/btrfs/ioctl.c         |  4 ++--

Acked-by: David Sterba <dsterba@suse.com>
Jeff Layton Dec. 5, 2019, 4:08 p.m. UTC | #3
On Thu, 2019-12-05 at 16:09 +0530, Ritesh Harjani wrote:
> This defines 4 more APIs which some of the filesystem needs
> and reduces the direct use of i_rwsem in filesystem drivers.
> Instead those are replaced with inode_lock/unlock_** APIs.
> 
> Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
> ---
>  fs/btrfs/delayed-inode.c |  2 +-
>  fs/btrfs/ioctl.c         |  4 ++--
>  fs/ceph/io.c             | 24 ++++++++++++------------
>  fs/nfs/io.c              | 24 ++++++++++++------------
>  fs/orangefs/file.c       |  4 ++--
>  fs/overlayfs/readdir.c   |  2 +-
>  fs/readdir.c             |  4 ++--
>  include/linux/fs.h       | 21 +++++++++++++++++++++
>  8 files changed, 53 insertions(+), 32 deletions(-)
> 
> diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
> index d3e15e1d4a91..c3e92f2fd915 100644
> --- a/fs/btrfs/delayed-inode.c
> +++ b/fs/btrfs/delayed-inode.c
> @@ -1644,7 +1644,7 @@ void btrfs_readdir_put_delayed_items(struct inode *inode,
>  	 * The VFS is going to do up_read(), so we need to downgrade back to a
>  	 * read lock.
>  	 */
> -	downgrade_write(&inode->i_rwsem);
> +	inode_lock_downgrade(inode);
>  }
>  
>  int btrfs_should_delete_dir_index(struct list_head *del_list,
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index a1ee0b775e65..1cbd763a46d8 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -955,7 +955,7 @@ static noinline int btrfs_mksubvol(const struct path *parent,
>  	struct dentry *dentry;
>  	int error;
>  
> -	error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
> +	error = inode_lock_killable_nested(dir, I_MUTEX_PARENT);
>  	if (error == -EINTR)
>  		return error;
>  
> @@ -2863,7 +2863,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
>  		goto out;
>  
>  
> -	err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
> +	err = inode_lock_killable_nested(dir, I_MUTEX_PARENT);
>  	if (err == -EINTR)
>  		goto out_drop_write;
>  	dentry = lookup_one_len(vol_args->name, parent, namelen);
> diff --git a/fs/ceph/io.c b/fs/ceph/io.c
> index 97602ea92ff4..e94186259c2e 100644
> --- a/fs/ceph/io.c
> +++ b/fs/ceph/io.c
> @@ -53,14 +53,14 @@ ceph_start_io_read(struct inode *inode)
>  	struct ceph_inode_info *ci = ceph_inode(inode);
>  
>  	/* Be an optimist! */
> -	down_read(&inode->i_rwsem);
> +	inode_lock_shared(inode);
>  	if (!(READ_ONCE(ci->i_ceph_flags) & CEPH_I_ODIRECT))
>  		return;
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  	/* Slow path.... */
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	ceph_block_o_direct(ci, inode);
> -	downgrade_write(&inode->i_rwsem);
> +	inode_lock_downgrade(inode);
>  }
>  
>  /**
> @@ -73,7 +73,7 @@ ceph_start_io_read(struct inode *inode)
>  void
>  ceph_end_io_read(struct inode *inode)
>  {
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  }
>  
>  /**
> @@ -86,7 +86,7 @@ ceph_end_io_read(struct inode *inode)
>  void
>  ceph_start_io_write(struct inode *inode)
>  {
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	ceph_block_o_direct(ceph_inode(inode), inode);
>  }
>  
> @@ -100,7 +100,7 @@ ceph_start_io_write(struct inode *inode)
>  void
>  ceph_end_io_write(struct inode *inode)
>  {
> -	up_write(&inode->i_rwsem);
> +	inode_unlock(inode);
>  }
>  
>  /* Call with exclusively locked inode->i_rwsem */
> @@ -139,14 +139,14 @@ ceph_start_io_direct(struct inode *inode)
>  	struct ceph_inode_info *ci = ceph_inode(inode);
>  
>  	/* Be an optimist! */
> -	down_read(&inode->i_rwsem);
> +	inode_lock_shared(inode);
>  	if (READ_ONCE(ci->i_ceph_flags) & CEPH_I_ODIRECT)
>  		return;
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  	/* Slow path.... */
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	ceph_block_buffered(ci, inode);
> -	downgrade_write(&inode->i_rwsem);
> +	inode_lock_downgrade(inode);
>  }
>  
>  /**
> @@ -159,5 +159,5 @@ ceph_start_io_direct(struct inode *inode)
>  void
>  ceph_end_io_direct(struct inode *inode)
>  {
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  }
> diff --git a/fs/nfs/io.c b/fs/nfs/io.c
> index 5088fda9b453..bf5ed7bea59d 100644
> --- a/fs/nfs/io.c
> +++ b/fs/nfs/io.c
> @@ -44,14 +44,14 @@ nfs_start_io_read(struct inode *inode)
>  {
>  	struct nfs_inode *nfsi = NFS_I(inode);
>  	/* Be an optimist! */
> -	down_read(&inode->i_rwsem);
> +	inode_lock_shared(inode);
>  	if (test_bit(NFS_INO_ODIRECT, &nfsi->flags) == 0)
>  		return;
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  	/* Slow path.... */
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	nfs_block_o_direct(nfsi, inode);
> -	downgrade_write(&inode->i_rwsem);
> +	inode_lock_downgrade(inode);
>  }
>  
>  /**
> @@ -64,7 +64,7 @@ nfs_start_io_read(struct inode *inode)
>  void
>  nfs_end_io_read(struct inode *inode)
>  {
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  }
>  
>  /**
> @@ -77,7 +77,7 @@ nfs_end_io_read(struct inode *inode)
>  void
>  nfs_start_io_write(struct inode *inode)
>  {
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	nfs_block_o_direct(NFS_I(inode), inode);
>  }
>  
> @@ -91,7 +91,7 @@ nfs_start_io_write(struct inode *inode)
>  void
>  nfs_end_io_write(struct inode *inode)
>  {
> -	up_write(&inode->i_rwsem);
> +	inode_unlock(inode);
>  }
>  
>  /* Call with exclusively locked inode->i_rwsem */
> @@ -124,14 +124,14 @@ nfs_start_io_direct(struct inode *inode)
>  {
>  	struct nfs_inode *nfsi = NFS_I(inode);
>  	/* Be an optimist! */
> -	down_read(&inode->i_rwsem);
> +	inode_lock_shared(inode);
>  	if (test_bit(NFS_INO_ODIRECT, &nfsi->flags) != 0)
>  		return;
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  	/* Slow path.... */
> -	down_write(&inode->i_rwsem);
> +	inode_lock(inode);
>  	nfs_block_buffered(nfsi, inode);
> -	downgrade_write(&inode->i_rwsem);
> +	inode_lock_downgrade(inode);
>  }
>  
>  /**
> @@ -144,5 +144,5 @@ nfs_start_io_direct(struct inode *inode)
>  void
>  nfs_end_io_direct(struct inode *inode)
>  {
> -	up_read(&inode->i_rwsem);
> +	inode_unlock_shared(inode);
>  }
> diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
> index a5612abc0936..6420503e1275 100644
> --- a/fs/orangefs/file.c
> +++ b/fs/orangefs/file.c
> @@ -328,14 +328,14 @@ static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
>  		ro->blksiz = iter->count;
>  	}
>  
> -	down_read(&file_inode(iocb->ki_filp)->i_rwsem);
> +	inode_lock_shared(file_inode(iocb->ki_filp));
>  	ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
>  	if (ret)
>  		goto out;
>  
>  	ret = generic_file_read_iter(iocb, iter);
>  out:
> -	up_read(&file_inode(iocb->ki_filp)->i_rwsem);
> +	inode_unlock_shared(file_inode(iocb->ki_filp));
>  	return ret;
>  }
>  
> diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
> index 47a91c9733a5..c203e73160b0 100644
> --- a/fs/overlayfs/readdir.c
> +++ b/fs/overlayfs/readdir.c
> @@ -273,7 +273,7 @@ static int ovl_check_whiteouts(struct dentry *dir, struct ovl_readdir_data *rdd)
>  
>  	old_cred = ovl_override_creds(rdd->dentry->d_sb);
>  
> -	err = down_write_killable(&dir->d_inode->i_rwsem);
> +	err = inode_lock_killable(dir->d_inode);
>  	if (!err) {
>  		while (rdd->first_maybe_whiteout) {
>  			p = rdd->first_maybe_whiteout;
> diff --git a/fs/readdir.c b/fs/readdir.c
> index d26d5ea4de7b..10a34efa0af0 100644
> --- a/fs/readdir.c
> +++ b/fs/readdir.c
> @@ -52,9 +52,9 @@ int iterate_dir(struct file *file, struct dir_context *ctx)
>  		goto out;
>  
>  	if (shared)
> -		res = down_read_killable(&inode->i_rwsem);
> +		res = inode_lock_shared_killable(inode);
>  	else
> -		res = down_write_killable(&inode->i_rwsem);
> +		res = inode_lock_killable(inode);
>  	if (res)
>  		goto out;
>  
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 98e0349adb52..2b407464fac1 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -831,6 +831,27 @@ static inline void inode_lock_shared_nested(struct inode *inode, unsigned subcla
>  	down_read_nested(&inode->i_rwsem, subclass);
>  }
>  
> +static inline void inode_lock_downgrade(struct inode *inode)
> +{
> +	downgrade_write(&inode->i_rwsem);
> +}
> +
> +static inline int inode_lock_killable(struct inode *inode)
> +{
> +	return down_write_killable(&inode->i_rwsem);
> +}
> +
> +static inline int inode_lock_shared_killable(struct inode *inode)
> +{
> +	return down_read_killable(&inode->i_rwsem);
> +}
> +
> +static inline int inode_lock_killable_nested(struct inode *inode,
> +					     unsigned subclass)
> +{
> +	return down_write_killable_nested(&inode->i_rwsem, subclass);
> +}
> +
>  void lock_two_nondirectories(struct inode *, struct inode*);
>  void unlock_two_nondirectories(struct inode *, struct inode*);
>  

Nice little cleanup.

Reviewed-by: Jeff Layton <jlayton@kernel.org>

Patch
diff mbox series

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index d3e15e1d4a91..c3e92f2fd915 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1644,7 +1644,7 @@  void btrfs_readdir_put_delayed_items(struct inode *inode,
 	 * The VFS is going to do up_read(), so we need to downgrade back to a
 	 * read lock.
 	 */
-	downgrade_write(&inode->i_rwsem);
+	inode_lock_downgrade(inode);
 }
 
 int btrfs_should_delete_dir_index(struct list_head *del_list,
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a1ee0b775e65..1cbd763a46d8 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -955,7 +955,7 @@  static noinline int btrfs_mksubvol(const struct path *parent,
 	struct dentry *dentry;
 	int error;
 
-	error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
+	error = inode_lock_killable_nested(dir, I_MUTEX_PARENT);
 	if (error == -EINTR)
 		return error;
 
@@ -2863,7 +2863,7 @@  static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 		goto out;
 
 
-	err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
+	err = inode_lock_killable_nested(dir, I_MUTEX_PARENT);
 	if (err == -EINTR)
 		goto out_drop_write;
 	dentry = lookup_one_len(vol_args->name, parent, namelen);
diff --git a/fs/ceph/io.c b/fs/ceph/io.c
index 97602ea92ff4..e94186259c2e 100644
--- a/fs/ceph/io.c
+++ b/fs/ceph/io.c
@@ -53,14 +53,14 @@  ceph_start_io_read(struct inode *inode)
 	struct ceph_inode_info *ci = ceph_inode(inode);
 
 	/* Be an optimist! */
-	down_read(&inode->i_rwsem);
+	inode_lock_shared(inode);
 	if (!(READ_ONCE(ci->i_ceph_flags) & CEPH_I_ODIRECT))
 		return;
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 	/* Slow path.... */
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	ceph_block_o_direct(ci, inode);
-	downgrade_write(&inode->i_rwsem);
+	inode_lock_downgrade(inode);
 }
 
 /**
@@ -73,7 +73,7 @@  ceph_start_io_read(struct inode *inode)
 void
 ceph_end_io_read(struct inode *inode)
 {
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 }
 
 /**
@@ -86,7 +86,7 @@  ceph_end_io_read(struct inode *inode)
 void
 ceph_start_io_write(struct inode *inode)
 {
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	ceph_block_o_direct(ceph_inode(inode), inode);
 }
 
@@ -100,7 +100,7 @@  ceph_start_io_write(struct inode *inode)
 void
 ceph_end_io_write(struct inode *inode)
 {
-	up_write(&inode->i_rwsem);
+	inode_unlock(inode);
 }
 
 /* Call with exclusively locked inode->i_rwsem */
@@ -139,14 +139,14 @@  ceph_start_io_direct(struct inode *inode)
 	struct ceph_inode_info *ci = ceph_inode(inode);
 
 	/* Be an optimist! */
-	down_read(&inode->i_rwsem);
+	inode_lock_shared(inode);
 	if (READ_ONCE(ci->i_ceph_flags) & CEPH_I_ODIRECT)
 		return;
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 	/* Slow path.... */
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	ceph_block_buffered(ci, inode);
-	downgrade_write(&inode->i_rwsem);
+	inode_lock_downgrade(inode);
 }
 
 /**
@@ -159,5 +159,5 @@  ceph_start_io_direct(struct inode *inode)
 void
 ceph_end_io_direct(struct inode *inode)
 {
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 }
diff --git a/fs/nfs/io.c b/fs/nfs/io.c
index 5088fda9b453..bf5ed7bea59d 100644
--- a/fs/nfs/io.c
+++ b/fs/nfs/io.c
@@ -44,14 +44,14 @@  nfs_start_io_read(struct inode *inode)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
 	/* Be an optimist! */
-	down_read(&inode->i_rwsem);
+	inode_lock_shared(inode);
 	if (test_bit(NFS_INO_ODIRECT, &nfsi->flags) == 0)
 		return;
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 	/* Slow path.... */
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	nfs_block_o_direct(nfsi, inode);
-	downgrade_write(&inode->i_rwsem);
+	inode_lock_downgrade(inode);
 }
 
 /**
@@ -64,7 +64,7 @@  nfs_start_io_read(struct inode *inode)
 void
 nfs_end_io_read(struct inode *inode)
 {
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 }
 
 /**
@@ -77,7 +77,7 @@  nfs_end_io_read(struct inode *inode)
 void
 nfs_start_io_write(struct inode *inode)
 {
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	nfs_block_o_direct(NFS_I(inode), inode);
 }
 
@@ -91,7 +91,7 @@  nfs_start_io_write(struct inode *inode)
 void
 nfs_end_io_write(struct inode *inode)
 {
-	up_write(&inode->i_rwsem);
+	inode_unlock(inode);
 }
 
 /* Call with exclusively locked inode->i_rwsem */
@@ -124,14 +124,14 @@  nfs_start_io_direct(struct inode *inode)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
 	/* Be an optimist! */
-	down_read(&inode->i_rwsem);
+	inode_lock_shared(inode);
 	if (test_bit(NFS_INO_ODIRECT, &nfsi->flags) != 0)
 		return;
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 	/* Slow path.... */
-	down_write(&inode->i_rwsem);
+	inode_lock(inode);
 	nfs_block_buffered(nfsi, inode);
-	downgrade_write(&inode->i_rwsem);
+	inode_lock_downgrade(inode);
 }
 
 /**
@@ -144,5 +144,5 @@  nfs_start_io_direct(struct inode *inode)
 void
 nfs_end_io_direct(struct inode *inode)
 {
-	up_read(&inode->i_rwsem);
+	inode_unlock_shared(inode);
 }
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
index a5612abc0936..6420503e1275 100644
--- a/fs/orangefs/file.c
+++ b/fs/orangefs/file.c
@@ -328,14 +328,14 @@  static ssize_t orangefs_file_read_iter(struct kiocb *iocb,
 		ro->blksiz = iter->count;
 	}
 
-	down_read(&file_inode(iocb->ki_filp)->i_rwsem);
+	inode_lock_shared(file_inode(iocb->ki_filp));
 	ret = orangefs_revalidate_mapping(file_inode(iocb->ki_filp));
 	if (ret)
 		goto out;
 
 	ret = generic_file_read_iter(iocb, iter);
 out:
-	up_read(&file_inode(iocb->ki_filp)->i_rwsem);
+	inode_unlock_shared(file_inode(iocb->ki_filp));
 	return ret;
 }
 
diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c
index 47a91c9733a5..c203e73160b0 100644
--- a/fs/overlayfs/readdir.c
+++ b/fs/overlayfs/readdir.c
@@ -273,7 +273,7 @@  static int ovl_check_whiteouts(struct dentry *dir, struct ovl_readdir_data *rdd)
 
 	old_cred = ovl_override_creds(rdd->dentry->d_sb);
 
-	err = down_write_killable(&dir->d_inode->i_rwsem);
+	err = inode_lock_killable(dir->d_inode);
 	if (!err) {
 		while (rdd->first_maybe_whiteout) {
 			p = rdd->first_maybe_whiteout;
diff --git a/fs/readdir.c b/fs/readdir.c
index d26d5ea4de7b..10a34efa0af0 100644
--- a/fs/readdir.c
+++ b/fs/readdir.c
@@ -52,9 +52,9 @@  int iterate_dir(struct file *file, struct dir_context *ctx)
 		goto out;
 
 	if (shared)
-		res = down_read_killable(&inode->i_rwsem);
+		res = inode_lock_shared_killable(inode);
 	else
-		res = down_write_killable(&inode->i_rwsem);
+		res = inode_lock_killable(inode);
 	if (res)
 		goto out;
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 98e0349adb52..2b407464fac1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -831,6 +831,27 @@  static inline void inode_lock_shared_nested(struct inode *inode, unsigned subcla
 	down_read_nested(&inode->i_rwsem, subclass);
 }
 
+static inline void inode_lock_downgrade(struct inode *inode)
+{
+	downgrade_write(&inode->i_rwsem);
+}
+
+static inline int inode_lock_killable(struct inode *inode)
+{
+	return down_write_killable(&inode->i_rwsem);
+}
+
+static inline int inode_lock_shared_killable(struct inode *inode)
+{
+	return down_read_killable(&inode->i_rwsem);
+}
+
+static inline int inode_lock_killable_nested(struct inode *inode,
+					     unsigned subclass)
+{
+	return down_write_killable_nested(&inode->i_rwsem, subclass);
+}
+
 void lock_two_nondirectories(struct inode *, struct inode*);
 void unlock_two_nondirectories(struct inode *, struct inode*);