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diff -ru /tmp/linux/linux-2.4.0.tar.bz2@/linux/fs/namei.c linux/fs/namei.c
--- /tmp/linux/linux-2.4.0.tar.bz2@/linux/fs/namei.c Fri Dec 29 23:07:23 2000
+++ linux/fs/namei.c Wed Jan 10 10:04:21 2001
@@ -99,6 +99,9 @@
* XEmacs seems to be relying on it...
*/
+/* lookup function for "virtual" files */
+struct dentry *(*lookup_virtual)(struct nameidata *, struct dentry *);
+
/* In order to reduce some races, while at the same time doing additional
* checking and hopefully speeding things up, we copy filenames to the
* kernel data space before using them..
@@ -265,9 +268,10 @@
* make sure that nobody added the entry to the dcache in the meantime..
* SMP-safe
*/
-static struct dentry * real_lookup(struct dentry * parent, struct qstr * name, int flags)
+static struct dentry * real_lookup(struct nameidata * nd, struct qstr * name, int flags)
{
struct dentry * result;
+ struct dentry *parent = nd->dentry;
struct inode *dir = parent->d_inode;
down(&dir->i_sem);
@@ -286,12 +290,24 @@
lock_kernel();
result = dir->i_op->lookup(dir, dentry);
unlock_kernel();
- if (result)
+ if (result) {
dput(dentry);
- else
+ up(&dir->i_sem);
+ }
+ else {
+ up(&dir->i_sem);
result = dentry;
- }
- up(&dir->i_sem);
+ /*
+ * If the dentry is negative it might
+ * refer to a 'virtual' file
+ */
+ if (lookup_virtual && !dentry->d_inode)
+ lookup_virtual(nd, dentry);
+ }
+ }
+ else
+ up(&dir->i_sem);
+
return result;
}
@@ -494,7 +510,7 @@
/* This does the actual lookups.. */
dentry = cached_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
if (!dentry) {
- dentry = real_lookup(nd->dentry, &this, LOOKUP_CONTINUE);
+ dentry = real_lookup(nd, &this, LOOKUP_CONTINUE);
err = PTR_ERR(dentry);
if (IS_ERR(dentry))
break;
@@ -557,7 +573,7 @@
}
dentry = cached_lookup(nd->dentry, &this, 0);
if (!dentry) {
- dentry = real_lookup(nd->dentry, &this, 0);
+ dentry = real_lookup(nd, &this, 0);
err = PTR_ERR(dentry);
if (IS_ERR(dentry))
break;
diff -ru /tmp/linux/linux-2.4.0.tar.bz2@/linux/fs/super.c linux/fs/super.c
--- /tmp/linux/linux-2.4.0.tar.bz2@/linux/fs/super.c Fri Dec 29 23:18:42 2000
+++ linux/fs/super.c Wed Jan 10 10:04:21 2001
@@ -47,7 +47,7 @@
* unmounting a filesystem and re-mounting it (or something
* else).
*/
-static DECLARE_MUTEX(mount_sem);
+DECLARE_MUTEX(mount_sem);
extern void wait_for_keypress(void);
@@ -303,9 +303,10 @@
* support for such beasts we'll have to change prototype.
*/
-static struct vfsmount *add_vfsmnt(struct nameidata *nd,
- struct dentry *root,
- const char *dev_name)
+struct vfsmount *add_vfsmnt(struct nameidata *nd,
+ struct dentry *root,
+ const char *dev_name,
+ struct mount_operations *mnt_op)
{
struct vfsmount *mnt;
struct super_block *sb = root->d_inode->i_sb;
@@ -330,6 +331,7 @@
mnt->mnt_owner = current->uid;
atomic_set(&mnt->mnt_count,1);
mnt->mnt_sb = sb;
+ mnt->mnt_op = mnt_op;
spin_lock(&dcache_lock);
if (nd && !IS_ROOT(nd->dentry) && d_unhashed(nd->dentry))
@@ -417,6 +419,8 @@
list_del(&mnt->mnt_child);
spin_unlock(&dcache_lock);
/* Now we can work safely */
+ if(mnt->mnt_op && mnt->mnt_op->release)
+ mnt->mnt_op->release(mnt);
if (mnt->mnt_parent != mnt)
mntput(mnt->mnt_parent);
@@ -979,7 +983,7 @@
put_unnamed_dev(dev);
return ERR_PTR(-EINVAL);
}
- mnt = add_vfsmnt(NULL, sb->s_root, NULL);
+ mnt = add_vfsmnt(NULL, sb->s_root, NULL, NULL);
if (!mnt) {
kill_super(sb, 0);
return ERR_PTR(-ENOMEM);
@@ -1010,7 +1014,23 @@
return 0;
}
-static int do_umount(struct vfsmount *mnt, int umount_root, int flags)
+static void try_umount_children(struct vfsmount *mnt)
+{
+ struct list_head *next, *curr;
+ struct vfsmount *child;
+
+ /* The mount list is protected by mount_sem */
+ curr = mnt->mnt_mounts.next;
+ while(curr != &mnt->mnt_mounts) {
+ next = curr->next;
+ child = list_entry(curr, struct vfsmount, mnt_child);
+ if(child->mnt_op && child->mnt_op->umount)
+ child->mnt_op->umount(child);
+ curr = next;
+ }
+}
+
+int do_umount(struct vfsmount *mnt, int umount_root, int flags)
{
struct super_block * sb = mnt->mnt_sb;
@@ -1036,6 +1056,9 @@
return retval;
}
+ /* umount any automatic mounts */
+ try_umount_children(mnt);
+
spin_lock(&dcache_lock);
if (mnt->mnt_instances.next != mnt->mnt_instances.prev) {
@@ -1213,7 +1236,7 @@
down(&new_nd.dentry->d_inode->i_zombie);
if (IS_DEADDIR(new_nd.dentry->d_inode))
err = -ENOENT;
- else if (add_vfsmnt(&new_nd, old_nd.dentry, old_nd.mnt->mnt_devname))
+ else if (add_vfsmnt(&new_nd, old_nd.dentry, old_nd.mnt->mnt_devname, NULL))
err = 0;
up(&new_nd.dentry->d_inode->i_zombie);
up(&mount_sem);
@@ -1398,7 +1421,7 @@
down(&nd.dentry->d_inode->i_zombie);
if (!IS_DEADDIR(nd.dentry->d_inode)) {
retval = -ENOMEM;
- mnt = add_vfsmnt(&nd, sb->s_root, dev_name);
+ mnt = add_vfsmnt(&nd, sb->s_root, dev_name, NULL);
}
up(&nd.dentry->d_inode->i_zombie);
if (!mnt)
@@ -1603,10 +1626,10 @@
devfs_mk_symlink (NULL, "root", DEVFS_FL_DEFAULT,
path + 5 + path_start, NULL, NULL);
memcpy (path + path_start, "/dev/", 5);
- vfsmnt = add_vfsmnt(NULL, sb->s_root, path + path_start);
+ vfsmnt = add_vfsmnt(NULL, sb->s_root, path + path_start, NULL);
}
else
- vfsmnt = add_vfsmnt(NULL, sb->s_root, "/dev/root");
+ vfsmnt = add_vfsmnt(NULL, sb->s_root, "/dev/root", NULL);
/* FIXME: if something will try to umount us right now... */
if (vfsmnt) {
set_fs_root(current->fs, vfsmnt, sb->s_root);
diff -ru /tmp/linux/linux-2.4.0.tar.bz2@/linux/include/linux/fs.h linux/include/linux/fs.h
--- /tmp/linux/linux-2.4.0.tar.bz2@/linux/include/linux/fs.h Thu Jan 4 23:50:47 2001
+++ linux/include/linux/fs.h Wed Jan 10 10:04:21 2001
@@ -874,6 +874,10 @@
extern void kern_umount(struct vfsmount *);
extern int may_umount(struct vfsmount *);
extern long do_mount(char *, char *, char *, unsigned long, void *);
+extern struct vfsmount *add_vfsmnt(struct nameidata *nd, struct dentry *root,
+ const char *dev_name,
+ struct mount_operations *mnt_op);
+extern int do_umount(struct vfsmount *mnt, int umount_root, int flags);
extern int vfs_statfs(struct super_block *, struct statfs *);
@@ -1163,6 +1167,9 @@
/* needed for stackable file system support */
extern loff_t default_llseek(struct file *file, loff_t offset, int origin);
+
+/* lookup function for "virtual" files */
+extern struct dentry *(*lookup_virtual)(struct nameidata *, struct dentry *);
extern int __user_walk(const char *, unsigned, struct nameidata *);
extern int path_init(const char *, unsigned, struct nameidata *);
diff -ru /tmp/linux/linux-2.4.0.tar.bz2@/linux/include/linux/mount.h linux/include/linux/mount.h
--- /tmp/linux/linux-2.4.0.tar.bz2@/linux/include/linux/mount.h Sun Sep 17 18:51:57 2000
+++ linux/include/linux/mount.h Wed Jan 10 10:04:21 2001
@@ -14,6 +14,8 @@
#define MNT_VISIBLE 1
+extern struct semaphore mount_sem;
+
struct vfsmount
{
struct dentry *mnt_mountpoint; /* dentry of mountpoint */
@@ -30,6 +32,20 @@
char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
struct list_head mnt_list;
uid_t mnt_owner;
+ struct mount_operations *mnt_op; /* Operations on vfsmount */
+};
+
+/*
+ * Mount operations:
+ * release(node) - called when this node has been umounted
+ * umount(node) - called when the parent is being umounted
+ *
+ * mount_sem is held in all
+ */
+
+struct mount_operations {
+ void (*release) (struct vfsmount *);
+ void (*umount) (struct vfsmount *);
};
static inline struct vfsmount *mntget(struct vfsmount *mnt)
diff -ru /tmp/linux/linux-2.4.0.tar.bz2@/linux/kernel/ksyms.c linux/kernel/ksyms.c
--- /tmp/linux/linux-2.4.0.tar.bz2@/linux/kernel/ksyms.c Wed Jan 3 01:45:37 2001
+++ linux/kernel/ksyms.c Wed Jan 10 10:04:21 2001
@@ -261,6 +261,9 @@
EXPORT_SYMBOL(filemap_sync);
EXPORT_SYMBOL(lock_page);
+/* lookup function for "virtual" files */
+EXPORT_SYMBOL(lookup_virtual);
+
/* device registration */
EXPORT_SYMBOL(register_chrdev);
EXPORT_SYMBOL(unregister_chrdev);
@@ -313,6 +316,9 @@
EXPORT_SYMBOL(kern_mount);
EXPORT_SYMBOL(kern_umount);
EXPORT_SYMBOL(may_umount);
+EXPORT_SYMBOL(add_vfsmnt);
+EXPORT_SYMBOL(do_umount);
+EXPORT_SYMBOL(mount_sem);
/* executable format registration */
EXPORT_SYMBOL(register_binfmt);
|
