vfs: spread struct mount - do_umount/propagate_mount_busy

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2011-11-24 21:35:16 -05:00
parent 44d964d609
commit 1ab5973862
3 changed files with 23 additions and 23 deletions

View file

@ -1180,7 +1180,7 @@ int may_umount(struct vfsmount *mnt)
int ret = 1; int ret = 1;
down_read(&namespace_sem); down_read(&namespace_sem);
br_write_lock(vfsmount_lock); br_write_lock(vfsmount_lock);
if (propagate_mount_busy(mnt, 2)) if (propagate_mount_busy(real_mount(mnt), 2))
ret = 0; ret = 0;
br_write_unlock(vfsmount_lock); br_write_unlock(vfsmount_lock);
up_read(&namespace_sem); up_read(&namespace_sem);
@ -1246,13 +1246,13 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill)
static void shrink_submounts(struct mount *mnt, struct list_head *umounts); static void shrink_submounts(struct mount *mnt, struct list_head *umounts);
static int do_umount(struct vfsmount *mnt, int flags) static int do_umount(struct mount *mnt, int flags)
{ {
struct super_block *sb = mnt->mnt_sb; struct super_block *sb = mnt->mnt.mnt_sb;
int retval; int retval;
LIST_HEAD(umount_list); LIST_HEAD(umount_list);
retval = security_sb_umount(mnt, flags); retval = security_sb_umount(&mnt->mnt, flags);
if (retval) if (retval)
return retval; return retval;
@ -1263,7 +1263,7 @@ static int do_umount(struct vfsmount *mnt, int flags)
* (2) the usage count == 1 [parent vfsmount] + 1 [sys_umount] * (2) the usage count == 1 [parent vfsmount] + 1 [sys_umount]
*/ */
if (flags & MNT_EXPIRE) { if (flags & MNT_EXPIRE) {
if (mnt == current->fs->root.mnt || if (&mnt->mnt == current->fs->root.mnt ||
flags & (MNT_FORCE | MNT_DETACH)) flags & (MNT_FORCE | MNT_DETACH))
return -EINVAL; return -EINVAL;
@ -1272,13 +1272,13 @@ static int do_umount(struct vfsmount *mnt, int flags)
* all race cases, but it's a slowpath. * all race cases, but it's a slowpath.
*/ */
br_write_lock(vfsmount_lock); br_write_lock(vfsmount_lock);
if (mnt_get_count(mnt) != 2) { if (mnt_get_count(&mnt->mnt) != 2) {
br_write_unlock(vfsmount_lock); br_write_unlock(vfsmount_lock);
return -EBUSY; return -EBUSY;
} }
br_write_unlock(vfsmount_lock); br_write_unlock(vfsmount_lock);
if (!xchg(&mnt->mnt_expiry_mark, 1)) if (!xchg(&mnt->mnt.mnt_expiry_mark, 1))
return -EAGAIN; return -EAGAIN;
} }
@ -1305,7 +1305,7 @@ static int do_umount(struct vfsmount *mnt, int flags)
* /reboot - static binary that would close all descriptors and * /reboot - static binary that would close all descriptors and
* call reboot(9). Then init(8) could umount root and exec /reboot. * call reboot(9). Then init(8) could umount root and exec /reboot.
*/ */
if (mnt == current->fs->root.mnt && !(flags & MNT_DETACH)) { if (&mnt->mnt == current->fs->root.mnt && !(flags & MNT_DETACH)) {
/* /*
* Special case for "unmounting" root ... * Special case for "unmounting" root ...
* we just try to remount it readonly. * we just try to remount it readonly.
@ -1322,12 +1322,12 @@ static int do_umount(struct vfsmount *mnt, int flags)
event++; event++;
if (!(flags & MNT_DETACH)) if (!(flags & MNT_DETACH))
shrink_submounts(real_mount(mnt), &umount_list); shrink_submounts(mnt, &umount_list);
retval = -EBUSY; retval = -EBUSY;
if (flags & MNT_DETACH || !propagate_mount_busy(mnt, 2)) { if (flags & MNT_DETACH || !propagate_mount_busy(mnt, 2)) {
if (!list_empty(&mnt->mnt_list)) if (!list_empty(&mnt->mnt.mnt_list))
umount_tree(real_mount(mnt), 1, &umount_list); umount_tree(mnt, 1, &umount_list);
retval = 0; retval = 0;
} }
br_write_unlock(vfsmount_lock); br_write_unlock(vfsmount_lock);
@ -1369,7 +1369,7 @@ SYSCALL_DEFINE2(umount, char __user *, name, int, flags)
if (!capable(CAP_SYS_ADMIN)) if (!capable(CAP_SYS_ADMIN))
goto dput_and_out; goto dput_and_out;
retval = do_umount(path.mnt, flags); retval = do_umount(real_mount(path.mnt), flags);
dput_and_out: dput_and_out:
/* we mustn't call path_put() as that would clear mnt_expiry_mark */ /* we mustn't call path_put() as that would clear mnt_expiry_mark */
dput(path.dentry); dput(path.dentry);
@ -2101,7 +2101,7 @@ void mark_mounts_for_expiry(struct list_head *mounts)
*/ */
list_for_each_entry_safe(mnt, next, mounts, mnt.mnt_expire) { list_for_each_entry_safe(mnt, next, mounts, mnt.mnt_expire) {
if (!xchg(&mnt->mnt.mnt_expiry_mark, 1) || if (!xchg(&mnt->mnt.mnt_expiry_mark, 1) ||
propagate_mount_busy(&mnt->mnt, 1)) propagate_mount_busy(mnt, 1))
continue; continue;
list_move(&mnt->mnt.mnt_expire, &graveyard); list_move(&mnt->mnt.mnt_expire, &graveyard);
} }
@ -2148,7 +2148,7 @@ static int select_submounts(struct mount *parent, struct list_head *graveyard)
goto repeat; goto repeat;
} }
if (!propagate_mount_busy(&mnt->mnt, 1)) { if (!propagate_mount_busy(mnt, 1)) {
list_move_tail(&mnt->mnt.mnt_expire, graveyard); list_move_tail(&mnt->mnt.mnt_expire, graveyard);
found++; found++;
} }

View file

@ -272,9 +272,9 @@ int propagate_mnt(struct vfsmount *dest_mnt, struct dentry *dest_dentry,
/* /*
* return true if the refcount is greater than count * return true if the refcount is greater than count
*/ */
static inline int do_refcount_check(struct vfsmount *mnt, int count) static inline int do_refcount_check(struct mount *mnt, int count)
{ {
int mycount = mnt_get_count(mnt) - mnt->mnt_ghosts; int mycount = mnt_get_count(&mnt->mnt) - mnt->mnt.mnt_ghosts;
return (mycount > count); return (mycount > count);
} }
@ -288,14 +288,14 @@ static inline int do_refcount_check(struct vfsmount *mnt, int count)
* *
* vfsmount lock must be held for write * vfsmount lock must be held for write
*/ */
int propagate_mount_busy(struct vfsmount *mnt, int refcnt) int propagate_mount_busy(struct mount *mnt, int refcnt)
{ {
struct vfsmount *m; struct vfsmount *m;
struct mount *child; struct mount *child;
struct vfsmount *parent = mnt->mnt_parent; struct vfsmount *parent = mnt->mnt.mnt_parent;
int ret = 0; int ret = 0;
if (mnt == parent) if (&mnt->mnt == parent)
return do_refcount_check(mnt, refcnt); return do_refcount_check(mnt, refcnt);
/* /*
@ -303,14 +303,14 @@ int propagate_mount_busy(struct vfsmount *mnt, int refcnt)
* If not, we don't have to go checking for all other * If not, we don't have to go checking for all other
* mounts * mounts
*/ */
if (!list_empty(&mnt->mnt_mounts) || do_refcount_check(mnt, refcnt)) if (!list_empty(&mnt->mnt.mnt_mounts) || do_refcount_check(mnt, refcnt))
return 1; return 1;
for (m = propagation_next(parent, parent); m; for (m = propagation_next(parent, parent); m;
m = propagation_next(m, parent)) { m = propagation_next(m, parent)) {
child = __lookup_mnt(m, mnt->mnt_mountpoint, 0); child = __lookup_mnt(m, mnt->mnt.mnt_mountpoint, 0);
if (child && list_empty(&child->mnt.mnt_mounts) && if (child && list_empty(&child->mnt.mnt_mounts) &&
(ret = do_refcount_check(&child->mnt, 1))) (ret = do_refcount_check(child, 1)))
break; break;
} }
return ret; return ret;

View file

@ -33,7 +33,7 @@ void change_mnt_propagation(struct mount *, int);
int propagate_mnt(struct vfsmount *, struct dentry *, struct vfsmount *, int propagate_mnt(struct vfsmount *, struct dentry *, struct vfsmount *,
struct list_head *); struct list_head *);
int propagate_umount(struct list_head *); int propagate_umount(struct list_head *);
int propagate_mount_busy(struct vfsmount *, int); int propagate_mount_busy(struct mount *, int);
void mnt_release_group_id(struct mount *); void mnt_release_group_id(struct mount *);
int get_dominating_id(struct vfsmount *mnt, const struct path *root); int get_dominating_id(struct vfsmount *mnt, const struct path *root);
unsigned int mnt_get_count(struct vfsmount *mnt); unsigned int mnt_get_count(struct vfsmount *mnt);