* Heavily rewritten for 'one fs - one tree' dcache architecture. AV, Mar 2000
*/
-#include <linux/config.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
/**
* alloc_super - create new superblock
+ * @type: filesystem type superblock should belong to
*
* Allocates and initializes a new &struct super_block. alloc_super()
* returns a pointer new superblock or %NULL if allocation had failed.
*/
-static struct super_block *alloc_super(void)
+static struct super_block *alloc_super(struct file_system_type *type)
{
struct super_block *s = kzalloc(sizeof(struct super_block), GFP_USER);
static struct super_operations default_op;
INIT_LIST_HEAD(&s->s_inodes);
init_rwsem(&s->s_umount);
mutex_init(&s->s_lock);
+ lockdep_set_class(&s->s_umount, &type->s_umount_key);
+ /*
+ * The locking rules for s_lock are up to the
+ * filesystem. For example ext3fs has different
+ * lock ordering than usbfs:
+ */
+ lockdep_set_class(&s->s_lock, &type->s_lock_key);
down_write(&s->s_umount);
s->s_count = S_BIAS;
atomic_set(&s->s_active, 1);
* that need destruction out of superblock, call generic_shutdown_super()
* and release aforementioned objects. Note: dentries and inodes _are_
* taken care of and do not need specific handling.
+ *
+ * Upon calling this function, the filesystem may no longer alter or
+ * rearrange the set of dentries belonging to this super_block, nor may it
+ * change the attachments of dentries to inodes.
*/
void generic_shutdown_super(struct super_block *sb)
{
- struct dentry *root = sb->s_root;
struct super_operations *sop = sb->s_op;
- if (root) {
- sb->s_root = NULL;
- shrink_dcache_parent(root);
- shrink_dcache_anon(&sb->s_anon);
- dput(root);
+ if (sb->s_root) {
+ shrink_dcache_for_umount(sb);
fsync_super(sb);
lock_super(sb);
sb->s_flags &= ~MS_ACTIVE;
}
if (!s) {
spin_unlock(&sb_lock);
- s = alloc_super();
+ s = alloc_super(type);
if (!s)
return ERR_PTR(-ENOMEM);
goto retry;
s = user_get_super(new_decode_dev(dev));
if (s == NULL)
goto out;
- err = vfs_statfs(s, &sbuf);
+ err = vfs_statfs(s->s_root, &sbuf);
drop_super(s);
if (err)
goto out;
}
}
-struct super_block *get_sb_bdev(struct file_system_type *fs_type,
+int get_sb_bdev(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data,
- int (*fill_super)(struct super_block *, void *, int))
+ int (*fill_super)(struct super_block *, void *, int),
+ struct vfsmount *mnt)
{
struct block_device *bdev;
struct super_block *s;
bdev = open_bdev_excl(dev_name, flags, fs_type);
if (IS_ERR(bdev))
- return (struct super_block *)bdev;
+ return PTR_ERR(bdev);
/*
* once the super is inserted into the list by sget, s_umount
s = sget(fs_type, test_bdev_super, set_bdev_super, bdev);
mutex_unlock(&bdev->bd_mount_mutex);
if (IS_ERR(s))
- goto out;
+ goto error_s;
if (s->s_root) {
if ((flags ^ s->s_flags) & MS_RDONLY) {
up_write(&s->s_umount);
deactivate_super(s);
- s = ERR_PTR(-EBUSY);
+ error = -EBUSY;
+ goto error_bdev;
}
- goto out;
+
+ close_bdev_excl(bdev);
} else {
char b[BDEVNAME_SIZE];
if (error) {
up_write(&s->s_umount);
deactivate_super(s);
- s = ERR_PTR(error);
- } else {
- s->s_flags |= MS_ACTIVE;
- bdev_uevent(bdev, KOBJ_MOUNT);
+ goto error;
}
+
+ s->s_flags |= MS_ACTIVE;
+ bdev_uevent(bdev, KOBJ_MOUNT);
}
- return s;
+ return simple_set_mnt(mnt, s);
-out:
+error_s:
+ error = PTR_ERR(s);
+error_bdev:
close_bdev_excl(bdev);
- return s;
+error:
+ return error;
}
EXPORT_SYMBOL(get_sb_bdev);
EXPORT_SYMBOL(kill_block_super);
-struct super_block *get_sb_nodev(struct file_system_type *fs_type,
+int get_sb_nodev(struct file_system_type *fs_type,
int flags, void *data,
- int (*fill_super)(struct super_block *, void *, int))
+ int (*fill_super)(struct super_block *, void *, int),
+ struct vfsmount *mnt)
{
int error;
struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL);
if (IS_ERR(s))
- return s;
+ return PTR_ERR(s);
s->s_flags = flags;
if (error) {
up_write(&s->s_umount);
deactivate_super(s);
- return ERR_PTR(error);
+ return error;
}
s->s_flags |= MS_ACTIVE;
- return s;
+ return simple_set_mnt(mnt, s);
}
EXPORT_SYMBOL(get_sb_nodev);
return 1;
}
-struct super_block *get_sb_single(struct file_system_type *fs_type,
+int get_sb_single(struct file_system_type *fs_type,
int flags, void *data,
- int (*fill_super)(struct super_block *, void *, int))
+ int (*fill_super)(struct super_block *, void *, int),
+ struct vfsmount *mnt)
{
struct super_block *s;
int error;
s = sget(fs_type, compare_single, set_anon_super, NULL);
if (IS_ERR(s))
- return s;
+ return PTR_ERR(s);
if (!s->s_root) {
s->s_flags = flags;
error = fill_super(s, data, flags & MS_SILENT ? 1 : 0);
if (error) {
up_write(&s->s_umount);
deactivate_super(s);
- return ERR_PTR(error);
+ return error;
}
s->s_flags |= MS_ACTIVE;
}
do_remount_sb(s, flags, data, 0);
- return s;
+ return simple_set_mnt(mnt, s);
}
EXPORT_SYMBOL(get_sb_single);
struct vfsmount *
-do_kern_mount(const char *fstype, int flags, const char *name, void *data)
+vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void *data)
{
- struct file_system_type *type = get_fs_type(fstype);
- struct super_block *sb;
struct vfsmount *mnt;
- int error;
+ struct super_block *sb;
char *secdata = NULL;
+ int error;
if (!type)
return ERR_PTR(-ENODEV);
- sb = ERR_PTR(-EPERM);
- if ((type->fs_flags & FS_BINARY_MOUNTDATA) &&
- !vx_capable(CAP_SYS_ADMIN, VXC_BINARY_MOUNT))
- goto out;
-
- sb = ERR_PTR(-ENOMEM);
+ error = -ENOMEM;
mnt = alloc_vfsmnt(name);
if (!mnt)
goto out;
if (data) {
secdata = alloc_secdata();
- if (!secdata) {
- sb = ERR_PTR(-ENOMEM);
+ if (!secdata)
goto out_mnt;
- }
error = security_sb_copy_data(type, data, secdata);
- if (error) {
- sb = ERR_PTR(error);
+ if (error)
goto out_free_secdata;
- }
}
- sb = type->get_sb(type, flags, name, data);
- if (IS_ERR(sb))
+ error = type->get_sb(type, flags, name, data, mnt);
+ if (error < 0)
goto out_free_secdata;
+ sb = mnt->mnt_sb;
error = -EPERM;
if (!capable(CAP_SYS_ADMIN) && !sb->s_bdev &&
(sb->s_magic != PROC_SUPER_MAGIC) &&
(sb->s_magic != DEVPTS_SUPER_MAGIC))
goto out_sb;
- error = security_sb_kern_mount(sb, secdata);
+ error = security_sb_kern_mount(sb, secdata);
if (error)
goto out_sb;
- mnt->mnt_sb = sb;
- mnt->mnt_root = dget(sb->s_root);
- mnt->mnt_mountpoint = sb->s_root;
+
+ mnt->mnt_mountpoint = mnt->mnt_root;
mnt->mnt_parent = mnt;
- up_write(&sb->s_umount);
+ up_write(&mnt->mnt_sb->s_umount);
free_secdata(secdata);
- put_filesystem(type);
return mnt;
out_sb:
- up_write(&sb->s_umount);
- deactivate_super(sb);
- sb = ERR_PTR(error);
+ dput(mnt->mnt_root);
+ up_write(&mnt->mnt_sb->s_umount);
+ deactivate_super(mnt->mnt_sb);
out_free_secdata:
free_secdata(secdata);
out_mnt:
free_vfsmnt(mnt);
out:
- put_filesystem(type);
- return (struct vfsmount *)sb;
+ return ERR_PTR(error);
}
-EXPORT_SYMBOL_GPL(do_kern_mount);
+EXPORT_SYMBOL_GPL(vfs_kern_mount);
+
+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 = ERR_PTR(-EPERM);
+ if ((type->fs_flags & FS_BINARY_MOUNTDATA) &&
+ !vx_capable(CAP_SYS_ADMIN, VXC_BINARY_MOUNT))
+ goto out_put;
+
+ mnt = vfs_kern_mount(type, flags, name, data);
+out_put:
+ put_filesystem(type);
+ return mnt;
+}
struct vfsmount *kern_mount(struct file_system_type *type)
{
- return do_kern_mount(type->name, 0, type->name, NULL);
+ return vfs_kern_mount(type, 0, type->name, NULL);
}
EXPORT_SYMBOL(kern_mount);
git://git.onelab.eu / linux-2.6.git / blobdiff