X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=fs%2Fnamespace.c;h=058a44865bebdad95cb9416eefcedd1dd1473c25;hb=f33b5d783b4f56be5ace6a1c98fb5f76b2d2d07d;hp=2019899f2ab822caec7dd235e8c610096549a93b;hpb=e532c37858fdcc18e9a91d24c2e22cd21aa22561;p=linux-2.6-omap-h63xx.git diff --git a/fs/namespace.c b/fs/namespace.c index 2019899f2ab..058a44865be 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -47,6 +48,10 @@ static int hash_mask __read_mostly, hash_bits __read_mostly; static kmem_cache_t *mnt_cache; static struct rw_semaphore namespace_sem; +/* /sys/fs */ +decl_subsys(fs, NULL, NULL); +EXPORT_SYMBOL_GPL(fs_subsys); + static inline unsigned long hash(struct vfsmount *mnt, struct dentry *dentry) { unsigned long tmp = ((unsigned long)mnt / L1_CACHE_BYTES); @@ -355,14 +360,14 @@ static int show_vfsmnt(struct seq_file *m, void *v) { MS_SYNCHRONOUS, ",sync" }, { MS_DIRSYNC, ",dirsync" }, { MS_MANDLOCK, ",mand" }, - { MS_NOATIME, ",noatime" }, - { MS_NODIRATIME, ",nodiratime" }, { 0, NULL } }; static struct proc_fs_info mnt_info[] = { { MNT_NOSUID, ",nosuid" }, { MNT_NODEV, ",nodev" }, { MNT_NOEXEC, ",noexec" }, + { MNT_NOATIME, ",noatime" }, + { MNT_NODIRATIME, ",nodiratime" }, { 0, NULL } }; struct proc_fs_info *fs_infop; @@ -451,7 +456,7 @@ EXPORT_SYMBOL(may_umount); void release_mounts(struct list_head *head) { struct vfsmount *mnt; - while(!list_empty(head)) { + while (!list_empty(head)) { mnt = list_entry(head->next, struct vfsmount, mnt_hash); list_del_init(&mnt->mnt_hash); if (mnt->mnt_parent != mnt) { @@ -489,7 +494,7 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill) p->mnt_namespace = NULL; list_del_init(&p->mnt_child); if (p->mnt_parent != p) - mnt->mnt_mountpoint->d_mounted--; + p->mnt_mountpoint->d_mounted--; change_mnt_propagation(p, MS_PRIVATE); } } @@ -814,7 +819,7 @@ static int graft_tree(struct vfsmount *mnt, struct nameidata *nd) return -ENOTDIR; err = -ENOENT; - down(&nd->dentry->d_inode->i_sem); + mutex_lock(&nd->dentry->d_inode->i_mutex); if (IS_DEADDIR(nd->dentry->d_inode)) goto out_unlock; @@ -826,7 +831,7 @@ static int graft_tree(struct vfsmount *mnt, struct nameidata *nd) if (IS_ROOT(nd->dentry) || !d_unhashed(nd->dentry)) err = attach_recursive_mnt(mnt, nd, NULL); out_unlock: - up(&nd->dentry->d_inode->i_sem); + mutex_unlock(&nd->dentry->d_inode->i_mutex); if (!err) security_sb_post_addmount(mnt, nd); return err; @@ -962,7 +967,7 @@ static int do_move_mount(struct nameidata *nd, char *old_name) goto out; err = -ENOENT; - down(&nd->dentry->d_inode->i_sem); + mutex_lock(&nd->dentry->d_inode->i_mutex); if (IS_DEADDIR(nd->dentry->d_inode)) goto out1; @@ -1004,7 +1009,7 @@ static int do_move_mount(struct nameidata *nd, char *old_name) list_del_init(&old_nd.mnt->mnt_expire); spin_unlock(&vfsmount_lock); out1: - up(&nd->dentry->d_inode->i_sem); + mutex_unlock(&nd->dentry->d_inode->i_mutex); out: up_write(&namespace_sem); if (!err) @@ -1286,7 +1291,13 @@ long do_mount(char *dev_name, char *dir_name, char *type_page, mnt_flags |= MNT_NODEV; if (flags & MS_NOEXEC) mnt_flags |= MNT_NOEXEC; - flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE); + if (flags & MS_NOATIME) + mnt_flags |= MNT_NOATIME; + if (flags & MS_NODIRATIME) + mnt_flags |= MNT_NODIRATIME; + + flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | + MS_NOATIME | MS_NODIRATIME); /* ... and get the mountpoint */ retval = path_lookup(dir_name, LOOKUP_FOLLOW, &nd); @@ -1314,27 +1325,17 @@ dput_out: return retval; } -int copy_namespace(int flags, struct task_struct *tsk) +/* + * Allocate a new namespace structure and populate it with contents + * copied from the namespace of the passed in task structure. + */ +struct namespace *dup_namespace(struct task_struct *tsk, struct fs_struct *fs) { struct namespace *namespace = tsk->namespace; struct namespace *new_ns; struct vfsmount *rootmnt = NULL, *pwdmnt = NULL, *altrootmnt = NULL; - struct fs_struct *fs = tsk->fs; struct vfsmount *p, *q; - if (!namespace) - return 0; - - get_namespace(namespace); - - if (!(flags & CLONE_NEWNS)) - return 0; - - if (!capable(CAP_SYS_ADMIN)) { - put_namespace(namespace); - return -EPERM; - } - new_ns = kmalloc(sizeof(struct namespace), GFP_KERNEL); if (!new_ns) goto out; @@ -1385,8 +1386,6 @@ int copy_namespace(int flags, struct task_struct *tsk) } up_write(&namespace_sem); - tsk->namespace = new_ns; - if (rootmnt) mntput(rootmnt); if (pwdmnt) @@ -1394,12 +1393,40 @@ int copy_namespace(int flags, struct task_struct *tsk) if (altrootmnt) mntput(altrootmnt); - put_namespace(namespace); - return 0; +out: + return new_ns; +} + +int copy_namespace(int flags, struct task_struct *tsk) +{ + struct namespace *namespace = tsk->namespace; + struct namespace *new_ns; + int err = 0; + + if (!namespace) + return 0; + + get_namespace(namespace); + + if (!(flags & CLONE_NEWNS)) + return 0; + + if (!capable(CAP_SYS_ADMIN)) { + err = -EPERM; + goto out; + } + + new_ns = dup_namespace(tsk, tsk->fs); + if (!new_ns) { + err = -ENOMEM; + goto out; + } + + tsk->namespace = new_ns; out: put_namespace(namespace); - return -ENOMEM; + return err; } asmlinkage long sys_mount(char __user * dev_name, char __user * dir_name, @@ -1526,6 +1553,10 @@ static void chroot_fs_refs(struct nameidata *old_nd, struct nameidata *new_nd) * pointed to by put_old must yield the same directory as new_root. No other * file system may be mounted on put_old. After all, new_root is a mountpoint. * + * Also, the current root cannot be on the 'rootfs' (initial ramfs) filesystem. + * See Documentation/filesystems/ramfs-rootfs-initramfs.txt for alternatives + * in this situation. + * * Notes: * - we don't move root/cwd if they are not at the root (reason: if something * cared enough to change them, it's probably wrong to force them elsewhere) @@ -1569,7 +1600,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root, user_nd.dentry = dget(current->fs->root); read_unlock(¤t->fs->lock); down_write(&namespace_sem); - down(&old_nd.dentry->d_inode->i_sem); + mutex_lock(&old_nd.dentry->d_inode->i_mutex); error = -EINVAL; if (IS_MNT_SHARED(old_nd.mnt) || IS_MNT_SHARED(new_nd.mnt->mnt_parent) || @@ -1622,7 +1653,7 @@ asmlinkage long sys_pivot_root(const char __user * new_root, path_release(&root_parent); path_release(&parent_nd); out2: - up(&old_nd.dentry->d_inode->i_sem); + mutex_unlock(&old_nd.dentry->d_inode->i_mutex); up_write(&namespace_sem); path_release(&user_nd); path_release(&old_nd); @@ -1714,6 +1745,7 @@ void __init mnt_init(unsigned long mempages) i--; } while (i); sysfs_init(); + subsystem_register(&fs_subsys); init_rootfs(); init_mount_tree(); }