diff options
| author | Ram Pai <linuxram@us.ibm.com> | 2005-11-07 17:21:01 -0500 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-11-07 21:18:11 -0500 |
| commit | 5afe00221389998a25d611dc7941c06580c29eb6 (patch) | |
| tree | 521270fb5974b42ac2b27666541f20fd375d8f66 /fs/namespace.c | |
| parent | a58b0eb8e64b78d9315a5491955e78b1391d42e5 (diff) | |
[PATCH] handling of slave mounts
This makes bind, rbind, move, clone namespace and umount operations
aware of the semantics of slave mount (see Documentation/sharedsubtree.txt
in the last patch of the series for detailed description).
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 77 |
1 files changed, 49 insertions, 28 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 46f99bc585bd..089670363704 100644 --- a/fs/namespace.c +++ b/fs/namespace.c | |||
| @@ -227,8 +227,17 @@ static struct vfsmount *clone_mnt(struct vfsmount *old, struct dentry *root, | |||
| 227 | mnt->mnt_mountpoint = mnt->mnt_root; | 227 | mnt->mnt_mountpoint = mnt->mnt_root; |
| 228 | mnt->mnt_parent = mnt; | 228 | mnt->mnt_parent = mnt; |
| 229 | 229 | ||
| 230 | if ((flag & CL_PROPAGATION) || IS_MNT_SHARED(old)) | 230 | if (flag & CL_SLAVE) { |
| 231 | list_add(&mnt->mnt_share, &old->mnt_share); | 231 | list_add(&mnt->mnt_slave, &old->mnt_slave_list); |
| 232 | mnt->mnt_master = old; | ||
| 233 | CLEAR_MNT_SHARED(mnt); | ||
| 234 | } else { | ||
| 235 | if ((flag & CL_PROPAGATION) || IS_MNT_SHARED(old)) | ||
| 236 | list_add(&mnt->mnt_share, &old->mnt_share); | ||
| 237 | if (IS_MNT_SLAVE(old)) | ||
| 238 | list_add(&mnt->mnt_slave, &old->mnt_slave); | ||
| 239 | mnt->mnt_master = old->mnt_master; | ||
| 240 | } | ||
| 232 | if (flag & CL_MAKE_SHARED) | 241 | if (flag & CL_MAKE_SHARED) |
| 233 | set_mnt_shared(mnt); | 242 | set_mnt_shared(mnt); |
| 234 | 243 | ||
| @@ -689,18 +698,18 @@ Enomem: | |||
| 689 | * | 698 | * |
| 690 | * NOTE: in the table below explains the semantics when a source mount | 699 | * NOTE: in the table below explains the semantics when a source mount |
| 691 | * of a given type is attached to a destination mount of a given type. | 700 | * of a given type is attached to a destination mount of a given type. |
| 692 | * --------------------------------------------- | 701 | * ------------------------------------------------------------- |
| 693 | * | BIND MOUNT OPERATION | | 702 | * | BIND MOUNT OPERATION | |
| 694 | * |******************************************** | 703 | * |************************************************************* |
| 695 | * | source-->| shared | private | | 704 | * | source-->| shared | private | slave | |
| 696 | * | dest | | | | 705 | * | dest | | | | |
| 697 | * | | | | | | 706 | * | | | | | | |
| 698 | * | v | | | | 707 | * | v | | | | |
| 699 | * |******************************************** | 708 | * |************************************************************* |
| 700 | * | shared | shared (++) | shared (+) | | 709 | * | shared | shared (++) | shared (+) | shared(+++)| |
| 701 | * | | | | | 710 | * | | | | | |
| 702 | * |non-shared| shared (+) | private | | 711 | * |non-shared| shared (+) | private | slave (*) | |
| 703 | * ********************************************* | 712 | * ************************************************************** |
| 704 | * A bind operation clones the source mount and mounts the clone on the | 713 | * A bind operation clones the source mount and mounts the clone on the |
| 705 | * destination mount. | 714 | * destination mount. |
| 706 | * | 715 | * |
| @@ -710,21 +719,33 @@ Enomem: | |||
| 710 | * (+) the cloned mount is created under the destination mount and is marked | 719 | * (+) the cloned mount is created under the destination mount and is marked |
| 711 | * as shared. The cloned mount is added to the peer group of the source | 720 | * as shared. The cloned mount is added to the peer group of the source |
| 712 | * mount. | 721 | * mount. |
| 713 | * --------------------------------------------- | 722 | * (+++) the mount is propagated to all the mounts in the propagation tree |
| 714 | * | MOVE MOUNT OPERATION | | 723 | * of the destination mount and the cloned mount is made slave |
| 715 | * |******************************************** | 724 | * of the same master as that of the source mount. The cloned mount |
| 716 | * | source-->| shared | private | | 725 | * is marked as 'shared and slave'. |
| 717 | * | dest | | | | 726 | * (*) the cloned mount is made a slave of the same master as that of the |
| 718 | * | | | | | | 727 | * source mount. |
| 719 | * | v | | | | 728 | * |
| 720 | * |******************************************** | 729 | * -------------------------------------------------------------- |
| 721 | * | shared | shared (+) | shared (+) | | 730 | * | MOVE MOUNT OPERATION | |
| 722 | * | | | | | 731 | * |************************************************************* |
| 723 | * |non-shared| shared (+*) | private | | 732 | * | source-->| shared | private | slave | |
| 724 | * ********************************************* | 733 | * | dest | | | | |
| 725 | * (+) the mount is moved to the destination. And is then propagated to all | 734 | * | | | | | | |
| 726 | * the mounts in the propagation tree of the destination mount. | 735 | * | v | | | | |
| 736 | * |************************************************************* | ||
| 737 | * | shared | shared (+) | shared (+) | shared(+++) | | ||
| 738 | * | | | | | | ||
| 739 | * |non-shared| shared (+*) | private | slave (*) | | ||
| 740 | * ************************************************************** | ||
| 741 | * | ||
| 742 | * (+) the mount is moved to the destination. And is then propagated to | ||
| 743 | * all the mounts in the propagation tree of the destination mount. | ||
| 727 | * (+*) the mount is moved to the destination. | 744 | * (+*) the mount is moved to the destination. |
| 745 | * (+++) the mount is moved to the destination and is then propagated to | ||
| 746 | * all the mounts belonging to the destination mount's propagation tree. | ||
| 747 | * the mount is marked as 'shared and slave'. | ||
| 748 | * (*) the mount continues to be a slave at the new location. | ||
| 728 | * | 749 | * |
| 729 | * if the source mount is a tree, the operations explained above is | 750 | * if the source mount is a tree, the operations explained above is |
| 730 | * applied to each mount in the tree. | 751 | * applied to each mount in the tree. |