anon_inodes: move allocation of anon_inode into ->mount()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-03-17 02:52:29 -04:00
parent 2226a288fa
commit ca7068c41a

View File

@ -39,19 +39,6 @@ static const struct dentry_operations anon_inodefs_dentry_operations = {
.d_dname = anon_inodefs_dname,
};
static struct dentry *anon_inodefs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_pseudo(fs_type, "anon_inode:", NULL,
&anon_inodefs_dentry_operations, ANON_INODE_FS_MAGIC);
}
static struct file_system_type anon_inode_fs_type = {
.name = "anon_inodefs",
.mount = anon_inodefs_mount,
.kill_sb = kill_anon_super,
};
/*
* nop .set_page_dirty method so that people can use .page_mkwrite on
* anon inodes.
@ -65,6 +52,62 @@ static const struct address_space_operations anon_aops = {
.set_page_dirty = anon_set_page_dirty,
};
/*
* A single inode exists for all anon_inode files. Contrary to pipes,
* anon_inode inodes have no associated per-instance data, so we need
* only allocate one of them.
*/
static struct inode *anon_inode_mkinode(struct super_block *s)
{
struct inode *inode = new_inode_pseudo(s);
if (!inode)
return ERR_PTR(-ENOMEM);
inode->i_ino = get_next_ino();
inode->i_fop = &anon_inode_fops;
inode->i_mapping->a_ops = &anon_aops;
/*
* Mark the inode dirty from the very beginning,
* that way it will never be moved to the dirty
* list because mark_inode_dirty() will think
* that it already _is_ on the dirty list.
*/
inode->i_state = I_DIRTY;
inode->i_mode = S_IRUSR | S_IWUSR;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
inode->i_flags |= S_PRIVATE;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
return inode;
}
static struct dentry *anon_inodefs_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
struct dentry *root;
root = mount_pseudo(fs_type, "anon_inode:", NULL,
&anon_inodefs_dentry_operations, ANON_INODE_FS_MAGIC);
if (!IS_ERR(root)) {
struct super_block *s = root->d_sb;
anon_inode_inode = anon_inode_mkinode(s);
if (IS_ERR(anon_inode_inode)) {
dput(root);
deactivate_locked_super(s);
root = ERR_CAST(anon_inode_inode);
}
}
return root;
}
static struct file_system_type anon_inode_fs_type = {
.name = "anon_inodefs",
.mount = anon_inodefs_mount,
.kill_sb = kill_anon_super,
};
/**
* anon_inode_getfile - creates a new file instance by hooking it up to an
* anonymous inode, and a dentry that describe the "class"
@ -180,38 +223,6 @@ int anon_inode_getfd(const char *name, const struct file_operations *fops,
}
EXPORT_SYMBOL_GPL(anon_inode_getfd);
/*
* A single inode exists for all anon_inode files. Contrary to pipes,
* anon_inode inodes have no associated per-instance data, so we need
* only allocate one of them.
*/
static struct inode *anon_inode_mkinode(void)
{
struct inode *inode = new_inode_pseudo(anon_inode_mnt->mnt_sb);
if (!inode)
return ERR_PTR(-ENOMEM);
inode->i_ino = get_next_ino();
inode->i_fop = &anon_inode_fops;
inode->i_mapping->a_ops = &anon_aops;
/*
* Mark the inode dirty from the very beginning,
* that way it will never be moved to the dirty
* list because mark_inode_dirty() will think
* that it already _is_ on the dirty list.
*/
inode->i_state = I_DIRTY;
inode->i_mode = S_IRUSR | S_IWUSR;
inode->i_uid = current_fsuid();
inode->i_gid = current_fsgid();
inode->i_flags |= S_PRIVATE;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
return inode;
}
static int __init anon_inode_init(void)
{
int error;
@ -224,16 +235,8 @@ static int __init anon_inode_init(void)
error = PTR_ERR(anon_inode_mnt);
goto err_unregister_filesystem;
}
anon_inode_inode = anon_inode_mkinode();
if (IS_ERR(anon_inode_inode)) {
error = PTR_ERR(anon_inode_inode);
goto err_mntput;
}
return 0;
err_mntput:
kern_unmount(anon_inode_mnt);
err_unregister_filesystem:
unregister_filesystem(&anon_inode_fs_type);
err_exit: