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>

3 files changed, 18 insertions, 0 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 472e8f8bc892..126198f5a67c 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -107,6 +107,9 @@ static int ocfs2_file_open(struct inode *inode, struct file *file)
         mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
                    file->f_path.dentry->d_name.len, file->f_path.dentry->d_name.name);
 
+        if (file->f_mode & FMODE_WRITE)
+                vfs_dq_init(inode);
+
         spin_lock(&oi->ip_lock);
 
         /* Check that the inode hasn't been wiped from disk by another
@@ -977,6 +980,8 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 
         size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
         if (size_change) {
+                vfs_dq_init(inode);
+
                 status = ocfs2_rw_lock(inode, 1);
                 if (status < 0) {
                         mlog_errno(status);
diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 00eb6a095e68..77681a690d16 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -971,6 +971,8 @@ void ocfs2_delete_inode(struct inode *inode)
                 goto bail;
         }
 
+        vfs_dq_init(inode);
+
         if (!ocfs2_inode_is_valid_to_delete(inode)) {
                 /* It's probably not necessary to truncate_inode_pages
                  * here but we do it for safety anyway (it will most
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 99766b6418eb..8b5b142eb638 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -244,6 +244,8 @@ static int ocfs2_mknod(struct inode *dir,
                    (unsigned long)dev, dentry->d_name.len,
                    dentry->d_name.name);
 
+        vfs_dq_init(dir);
+
         /* get our super block */
         osb = OCFS2_SB(dir->i_sb);
 
@@ -632,6 +634,8 @@ static int ocfs2_link(struct dentry *old_dentry,
         if (S_ISDIR(inode->i_mode))
                 return -EPERM;
 
+        vfs_dq_init(dir);
+
         err = ocfs2_inode_lock_nested(dir, &parent_fe_bh, 1, OI_LS_PARENT);
         if (err < 0) {
                 if (err != -ENOENT)
@@ -787,6 +791,8 @@ static int ocfs2_unlink(struct inode *dir,
         mlog_entry("(0x%p, 0x%p, '%.*s')\n", dir, dentry,
                    dentry->d_name.len, dentry->d_name.name);
 
+        vfs_dq_init(dir);
+
         BUG_ON(dentry->d_parent->d_inode != dir);
 
         mlog(0, "ino = %llu\n", (unsigned long long)OCFS2_I(inode)->ip_blkno);
@@ -1047,6 +1053,9 @@ static int ocfs2_rename(struct inode *old_dir,
                    old_dentry->d_name.len, old_dentry->d_name.name,
                    new_dentry->d_name.len, new_dentry->d_name.name);
 
+        vfs_dq_init(old_dir);
+        vfs_dq_init(new_dir);
+
         osb = OCFS2_SB(old_dir->i_sb);
 
         if (new_inode) {
@@ -1595,6 +1604,8 @@ static int ocfs2_symlink(struct inode *dir,
         mlog_entry("(0x%p, 0x%p, symname='%s' actual='%.*s')\n", dir,
                    dentry, symname, dentry->d_name.len, dentry->d_name.name);
 
+        vfs_dq_init(dir);
+
         sb = dir->i_sb;
         osb = OCFS2_SB(sb);