dquot: move dquot initialization responsibility into the filesystem

Currently various places in the VFS call vfs_dq_init directly.  This means
we tie the quota code into the VFS.  Get rid of that and make the
filesystem responsible for the initialization.   For most metadata operations
this is a straight forward move into the methods, but for truncate and
open it's a bit more complicated.

For truncate we currently only call vfs_dq_init for the sys_truncate case
because open already takes care of it for ftruncate and open(O_TRUNC) - the
new code causes an additional vfs_dq_init for those which is harmless.

For open the initialization is moved from do_filp_open into the open method,
which means it happens slightly earlier now, and only for regular files.
The latter is fine because we don't need to initialize it for operations
on special files, and we already do it as part of the namespace operations
for directories.

Add a dquot_file_open helper that filesystems that support generic quotas
can use to fill in ->open.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 15 insertions, 0 deletions

diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c
index 1d1390afe55e..b7cc29da50b4 100644
--- a/fs/jfs/namei.c
+++ b/fs/jfs/namei.c
@@ -85,6 +85,8 @@ static int jfs_create(struct inode *dip, struct dentry *dentry, int mode,
 
 	jfs_info("jfs_create: dip:0x%p name:%s", dip, dentry->d_name.name);
 
+	vfs_dq_init(dip);
+
 	/*
 	 * search parent directory for entry/freespace
 	 * (dtSearch() returns parent directory page pinned)
@@ -215,6 +217,8 @@ static int jfs_mkdir(struct inode *dip, struct dentry *dentry, int mode)
 
 	jfs_info("jfs_mkdir: dip:0x%p name:%s", dip, dentry->d_name.name);
 
+	vfs_dq_init(dip);
+
 	/* link count overflow on parent directory ? */
 	if (dip->i_nlink == JFS_LINK_MAX) {
 		rc = -EMLINK;
@@ -356,6 +360,7 @@ static int jfs_rmdir(struct inode *dip, struct dentry *dentry)
 	jfs_info("jfs_rmdir: dip:0x%p name:%s", dip, dentry->d_name.name);
 
 	/* Init inode for quota operations. */
+	vfs_dq_init(dip);
 	vfs_dq_init(ip);
 
 	/* directory must be empty to be removed */
@@ -483,6 +488,7 @@ static int jfs_unlink(struct inode *dip, struct dentry *dentry)
 	jfs_info("jfs_unlink: dip:0x%p name:%s", dip, dentry->d_name.name);
 
 	/* Init inode for quota operations. */
+	vfs_dq_init(dip);
 	vfs_dq_init(ip);
 
 	if ((rc = get_UCSname(&dname, dentry)))
@@ -805,6 +811,8 @@ static int jfs_link(struct dentry *old_dentry,
 	if (ip->i_nlink == 0)
 		return -ENOENT;
 
+	vfs_dq_init(dir);
+
 	tid = txBegin(ip->i_sb, 0);
 
 	mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
@@ -896,6 +904,8 @@ static int jfs_symlink(struct inode *dip, struct dentry *dentry,
 
 	jfs_info("jfs_symlink: dip:0x%p name:%s", dip, name);
 
+	vfs_dq_init(dip);
+
 	ssize = strlen(name) + 1;
 
 	/*
@@ -1087,6 +1097,9 @@ static int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	jfs_info("jfs_rename: %s %s", old_dentry->d_name.name,
 		 new_dentry->d_name.name);
 
+	vfs_dq_init(old_dir);
+	vfs_dq_init(new_dir);
+
 	old_ip = old_dentry->d_inode;
 	new_ip = new_dentry->d_inode;
 
@@ -1360,6 +1373,8 @@ static int jfs_mknod(struct inode *dir, struct dentry *dentry,
 
 	jfs_info("jfs_mknod: %s", dentry->d_name.name);
 
+	vfs_dq_init(dir);
+
 	if ((rc = get_UCSname(&dname, dentry)))
 		goto out;