vfs: split off vfsmount-related parts of vfs_kern_mount()
new function: mount_fs(). Does all work done by vfs_kern_mount() except the allocation and filling of vfsmount; returns root dentry or ERR_PTR(). vfs_kern_mount() switched to using it and taken to fs/namespace.c, along with its wrappers. alloc_vfsmnt()/free_vfsmnt() made static. functions in namespace.c slightly reordered. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro
parent
fbe0aa1f3d
commit
9d412a43c3
@ -12,6 +12,7 @@
|
||||
#include <linux/lglock.h>
|
||||
|
||||
struct super_block;
|
||||
struct file_system_type;
|
||||
struct linux_binprm;
|
||||
struct path;
|
||||
|
||||
@ -61,8 +62,6 @@ extern int check_unsafe_exec(struct linux_binprm *);
|
||||
extern int copy_mount_options(const void __user *, unsigned long *);
|
||||
extern int copy_mount_string(const void __user *, char **);
|
||||
|
||||
extern void free_vfsmnt(struct vfsmount *);
|
||||
extern struct vfsmount *alloc_vfsmnt(const char *);
|
||||
extern unsigned int mnt_get_count(struct vfsmount *mnt);
|
||||
extern struct vfsmount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
|
||||
extern void mnt_set_mountpoint(struct vfsmount *, struct dentry *,
|
||||
@ -99,6 +98,8 @@ extern struct file *get_empty_filp(void);
|
||||
extern int do_remount_sb(struct super_block *, int, void *, int);
|
||||
extern void __put_super(struct super_block *sb);
|
||||
extern void put_super(struct super_block *sb);
|
||||
extern struct dentry *mount_fs(struct file_system_type *,
|
||||
int, const char *, void *);
|
||||
|
||||
/*
|
||||
* open.c
|
||||
|
||||
153
fs/namespace.c
153
fs/namespace.c
@ -196,7 +196,7 @@ unsigned int mnt_get_count(struct vfsmount *mnt)
|
||||
#endif
|
||||
}
|
||||
|
||||
struct vfsmount *alloc_vfsmnt(const char *name)
|
||||
static struct vfsmount *alloc_vfsmnt(const char *name)
|
||||
{
|
||||
struct vfsmount *mnt = kmem_cache_zalloc(mnt_cache, GFP_KERNEL);
|
||||
if (mnt) {
|
||||
@ -466,7 +466,7 @@ static void __mnt_unmake_readonly(struct vfsmount *mnt)
|
||||
br_write_unlock(vfsmount_lock);
|
||||
}
|
||||
|
||||
void free_vfsmnt(struct vfsmount *mnt)
|
||||
static void free_vfsmnt(struct vfsmount *mnt)
|
||||
{
|
||||
kfree(mnt->mnt_devname);
|
||||
mnt_free_id(mnt);
|
||||
@ -670,6 +670,36 @@ static struct vfsmount *skip_mnt_tree(struct vfsmount *p)
|
||||
return p;
|
||||
}
|
||||
|
||||
struct vfsmount *
|
||||
vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void *data)
|
||||
{
|
||||
struct vfsmount *mnt;
|
||||
struct dentry *root;
|
||||
|
||||
if (!type)
|
||||
return ERR_PTR(-ENODEV);
|
||||
|
||||
mnt = alloc_vfsmnt(name);
|
||||
if (!mnt)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
if (flags & MS_KERNMOUNT)
|
||||
mnt->mnt_flags = MNT_INTERNAL;
|
||||
|
||||
root = mount_fs(type, flags, name, data);
|
||||
if (IS_ERR(root)) {
|
||||
free_vfsmnt(mnt);
|
||||
return ERR_CAST(root);
|
||||
}
|
||||
|
||||
mnt->mnt_root = root;
|
||||
mnt->mnt_sb = root->d_sb;
|
||||
mnt->mnt_mountpoint = mnt->mnt_root;
|
||||
mnt->mnt_parent = mnt;
|
||||
return mnt;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(vfs_kern_mount);
|
||||
|
||||
static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root,
|
||||
int flag)
|
||||
{
|
||||
@ -1905,7 +1935,81 @@ out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int do_add_mount(struct vfsmount *, struct path *, int);
|
||||
static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
|
||||
{
|
||||
int err;
|
||||
const char *subtype = strchr(fstype, '.');
|
||||
if (subtype) {
|
||||
subtype++;
|
||||
err = -EINVAL;
|
||||
if (!subtype[0])
|
||||
goto err;
|
||||
} else
|
||||
subtype = "";
|
||||
|
||||
mnt->mnt_sb->s_subtype = kstrdup(subtype, GFP_KERNEL);
|
||||
err = -ENOMEM;
|
||||
if (!mnt->mnt_sb->s_subtype)
|
||||
goto err;
|
||||
return mnt;
|
||||
|
||||
err:
|
||||
mntput(mnt);
|
||||
return ERR_PTR(err);
|
||||
}
|
||||
|
||||
struct vfsmount *
|
||||
do_kern_mount(const char *fstype, int flags, const char *name, void *data)
|
||||
{
|
||||
struct file_system_type *type = get_fs_type(fstype);
|
||||
struct vfsmount *mnt;
|
||||
if (!type)
|
||||
return ERR_PTR(-ENODEV);
|
||||
mnt = vfs_kern_mount(type, flags, name, data);
|
||||
if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
|
||||
!mnt->mnt_sb->s_subtype)
|
||||
mnt = fs_set_subtype(mnt, fstype);
|
||||
put_filesystem(type);
|
||||
return mnt;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(do_kern_mount);
|
||||
|
||||
/*
|
||||
* add a mount into a namespace's mount tree
|
||||
*/
|
||||
static int do_add_mount(struct vfsmount *newmnt, struct path *path, int mnt_flags)
|
||||
{
|
||||
int err;
|
||||
|
||||
mnt_flags &= ~(MNT_SHARED | MNT_WRITE_HOLD | MNT_INTERNAL);
|
||||
|
||||
down_write(&namespace_sem);
|
||||
/* Something was mounted here while we slept */
|
||||
err = follow_down(path, true);
|
||||
if (err < 0)
|
||||
goto unlock;
|
||||
|
||||
err = -EINVAL;
|
||||
if (!(mnt_flags & MNT_SHRINKABLE) && !check_mnt(path->mnt))
|
||||
goto unlock;
|
||||
|
||||
/* Refuse the same filesystem on the same mount point */
|
||||
err = -EBUSY;
|
||||
if (path->mnt->mnt_sb == newmnt->mnt_sb &&
|
||||
path->mnt->mnt_root == path->dentry)
|
||||
goto unlock;
|
||||
|
||||
err = -EINVAL;
|
||||
if (S_ISLNK(newmnt->mnt_root->d_inode->i_mode))
|
||||
goto unlock;
|
||||
|
||||
newmnt->mnt_flags = mnt_flags;
|
||||
err = graft_tree(newmnt, path);
|
||||
|
||||
unlock:
|
||||
up_write(&namespace_sem);
|
||||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* create a new mount for userspace and request it to be added into the
|
||||
@ -1965,43 +2069,6 @@ fail:
|
||||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* add a mount into a namespace's mount tree
|
||||
*/
|
||||
static int do_add_mount(struct vfsmount *newmnt, struct path *path, int mnt_flags)
|
||||
{
|
||||
int err;
|
||||
|
||||
mnt_flags &= ~(MNT_SHARED | MNT_WRITE_HOLD | MNT_INTERNAL);
|
||||
|
||||
down_write(&namespace_sem);
|
||||
/* Something was mounted here while we slept */
|
||||
err = follow_down(path, true);
|
||||
if (err < 0)
|
||||
goto unlock;
|
||||
|
||||
err = -EINVAL;
|
||||
if (!(mnt_flags & MNT_SHRINKABLE) && !check_mnt(path->mnt))
|
||||
goto unlock;
|
||||
|
||||
/* Refuse the same filesystem on the same mount point */
|
||||
err = -EBUSY;
|
||||
if (path->mnt->mnt_sb == newmnt->mnt_sb &&
|
||||
path->mnt->mnt_root == path->dentry)
|
||||
goto unlock;
|
||||
|
||||
err = -EINVAL;
|
||||
if (S_ISLNK(newmnt->mnt_root->d_inode->i_mode))
|
||||
goto unlock;
|
||||
|
||||
newmnt->mnt_flags = mnt_flags;
|
||||
err = graft_tree(newmnt, path);
|
||||
|
||||
unlock:
|
||||
up_write(&namespace_sem);
|
||||
return err;
|
||||
}
|
||||
|
||||
/**
|
||||
* mnt_set_expiry - Put a mount on an expiration list
|
||||
* @mnt: The mount to list.
|
||||
@ -2660,3 +2727,9 @@ void put_mnt_ns(struct mnt_namespace *ns)
|
||||
kfree(ns);
|
||||
}
|
||||
EXPORT_SYMBOL(put_mnt_ns);
|
||||
|
||||
struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
|
||||
{
|
||||
return vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(kern_mount_data);
|
||||
|
||||
96
fs/super.c
96
fs/super.c
@ -910,29 +910,18 @@ struct dentry *mount_single(struct file_system_type *fs_type,
|
||||
}
|
||||
EXPORT_SYMBOL(mount_single);
|
||||
|
||||
struct vfsmount *
|
||||
vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void *data)
|
||||
struct dentry *
|
||||
mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
|
||||
{
|
||||
struct vfsmount *mnt;
|
||||
struct dentry *root;
|
||||
struct super_block *sb;
|
||||
char *secdata = NULL;
|
||||
int error;
|
||||
|
||||
if (!type)
|
||||
return ERR_PTR(-ENODEV);
|
||||
|
||||
error = -ENOMEM;
|
||||
mnt = alloc_vfsmnt(name);
|
||||
if (!mnt)
|
||||
goto out;
|
||||
|
||||
if (flags & MS_KERNMOUNT)
|
||||
mnt->mnt_flags = MNT_INTERNAL;
|
||||
int error = -ENOMEM;
|
||||
|
||||
if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
|
||||
secdata = alloc_secdata();
|
||||
if (!secdata)
|
||||
goto out_mnt;
|
||||
goto out;
|
||||
|
||||
error = security_sb_copy_data(data, secdata);
|
||||
if (error)
|
||||
@ -944,13 +933,12 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
|
||||
error = PTR_ERR(root);
|
||||
goto out_free_secdata;
|
||||
}
|
||||
mnt->mnt_root = root;
|
||||
mnt->mnt_sb = root->d_sb;
|
||||
BUG_ON(!mnt->mnt_sb);
|
||||
WARN_ON(!mnt->mnt_sb->s_bdi);
|
||||
mnt->mnt_sb->s_flags |= MS_BORN;
|
||||
sb = root->d_sb;
|
||||
BUG_ON(!sb);
|
||||
WARN_ON(!sb->s_bdi);
|
||||
sb->s_flags |= MS_BORN;
|
||||
|
||||
error = security_sb_kern_mount(mnt->mnt_sb, flags, secdata);
|
||||
error = security_sb_kern_mount(sb, flags, secdata);
|
||||
if (error)
|
||||
goto out_sb;
|
||||
|
||||
@ -961,27 +949,21 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
|
||||
* violate this rule. This warning should be either removed or
|
||||
* converted to a BUG() in 2.6.34.
|
||||
*/
|
||||
WARN((mnt->mnt_sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "
|
||||
"negative value (%lld)\n", type->name, mnt->mnt_sb->s_maxbytes);
|
||||
WARN((sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "
|
||||
"negative value (%lld)\n", type->name, sb->s_maxbytes);
|
||||
|
||||
mnt->mnt_mountpoint = mnt->mnt_root;
|
||||
mnt->mnt_parent = mnt;
|
||||
up_write(&mnt->mnt_sb->s_umount);
|
||||
up_write(&sb->s_umount);
|
||||
free_secdata(secdata);
|
||||
return mnt;
|
||||
return root;
|
||||
out_sb:
|
||||
dput(mnt->mnt_root);
|
||||
deactivate_locked_super(mnt->mnt_sb);
|
||||
dput(root);
|
||||
deactivate_locked_super(sb);
|
||||
out_free_secdata:
|
||||
free_secdata(secdata);
|
||||
out_mnt:
|
||||
free_vfsmnt(mnt);
|
||||
out:
|
||||
return ERR_PTR(error);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL_GPL(vfs_kern_mount);
|
||||
|
||||
/**
|
||||
* freeze_super - lock the filesystem and force it into a consistent state
|
||||
* @sb: the super to lock
|
||||
@ -1071,49 +1053,3 @@ out:
|
||||
return 0;
|
||||
}
|
||||
EXPORT_SYMBOL(thaw_super);
|
||||
|
||||
static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
|
||||
{
|
||||
int err;
|
||||
const char *subtype = strchr(fstype, '.');
|
||||
if (subtype) {
|
||||
subtype++;
|
||||
err = -EINVAL;
|
||||
if (!subtype[0])
|
||||
goto err;
|
||||
} else
|
||||
subtype = "";
|
||||
|
||||
mnt->mnt_sb->s_subtype = kstrdup(subtype, GFP_KERNEL);
|
||||
err = -ENOMEM;
|
||||
if (!mnt->mnt_sb->s_subtype)
|
||||
goto err;
|
||||
return mnt;
|
||||
|
||||
err:
|
||||
mntput(mnt);
|
||||
return ERR_PTR(err);
|
||||
}
|
||||
|
||||
struct vfsmount *
|
||||
do_kern_mount(const char *fstype, int flags, const char *name, void *data)
|
||||
{
|
||||
struct file_system_type *type = get_fs_type(fstype);
|
||||
struct vfsmount *mnt;
|
||||
if (!type)
|
||||
return ERR_PTR(-ENODEV);
|
||||
mnt = vfs_kern_mount(type, flags, name, data);
|
||||
if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
|
||||
!mnt->mnt_sb->s_subtype)
|
||||
mnt = fs_set_subtype(mnt, fstype);
|
||||
put_filesystem(type);
|
||||
return mnt;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(do_kern_mount);
|
||||
|
||||
struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
|
||||
{
|
||||
return vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL_GPL(kern_mount_data);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user