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| author | Miklos Szeredi <mszeredi@suse.cz> | 2011-11-21 12:11:30 +0100 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-01-06 23:20:12 -0500 |
| commit | 39f7c4db1d2d9e2e2a90abdf34811783089d217d (patch) | |
| tree | cbc3496ce21e26b5891bb4c4d4155853317ddfb3 | |
| parent | 34c80b1d93e6e20ca9dea0baf583a5b5510d92d4 (diff) | |
| download | op-kernel-dev-39f7c4db1d2d9e2e2a90abdf34811783089d217d.zip op-kernel-dev-39f7c4db1d2d9e2e2a90abdf34811783089d217d.tar.gz | |
vfs: keep list of mounts for each superblock
Keep track of vfsmounts belonging to a superblock. List is protected
by vfsmount_lock.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | fs/mount.h | 1 | ||||
| -rw-r--r-- | fs/namespace.c | 7 | ||||
| -rw-r--r-- | fs/super.c | 2 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 |
4 files changed, 11 insertions, 0 deletions
@@ -29,6 +29,7 @@ struct mount { #endif struct list_head mnt_mounts; /* list of children, anchored here */ struct list_head mnt_child; /* and going through their mnt_child */ + struct list_head mnt_instance; /* mount instance on sb->s_mounts */ const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ struct list_head mnt_list; struct list_head mnt_expire; /* link in fs-specific expiry list */ diff --git a/fs/namespace.c b/fs/namespace.c index db65e2e..145217b 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -671,6 +671,9 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void mnt->mnt.mnt_sb = root->d_sb; mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; + br_write_lock(vfsmount_lock); + list_add_tail(&mnt->mnt_instance, &root->d_sb->s_mounts); + br_write_unlock(vfsmount_lock); return &mnt->mnt; } EXPORT_SYMBOL_GPL(vfs_kern_mount); @@ -699,6 +702,9 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root, mnt->mnt.mnt_root = dget(root); mnt->mnt_mountpoint = mnt->mnt.mnt_root; mnt->mnt_parent = mnt; + br_write_lock(vfsmount_lock); + list_add_tail(&mnt->mnt_instance, &sb->s_mounts); + br_write_unlock(vfsmount_lock); if (flag & CL_SLAVE) { list_add(&mnt->mnt_slave, &old->mnt_slave_list); @@ -781,6 +787,7 @@ put_again: acct_auto_close_mnt(&mnt->mnt); goto put_again; } + list_del(&mnt->mnt_instance); br_write_unlock(vfsmount_lock); mntfree(mnt); } @@ -142,6 +142,7 @@ static struct super_block *alloc_super(struct file_system_type *type) INIT_LIST_HEAD(&s->s_dentry_lru); INIT_LIST_HEAD(&s->s_inode_lru); spin_lock_init(&s->s_inode_lru_lock); + INIT_LIST_HEAD(&s->s_mounts); init_rwsem(&s->s_umount); mutex_init(&s->s_lock); lockdep_set_class(&s->s_umount, &type->s_umount_key); @@ -200,6 +201,7 @@ static inline void destroy_super(struct super_block *s) free_percpu(s->s_files); #endif security_sb_free(s); + WARN_ON(!list_empty(&s->s_mounts)); kfree(s->s_subtype); kfree(s->s_options); kfree(s); diff --git a/include/linux/fs.h b/include/linux/fs.h index cc1021f..03385ac 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1428,6 +1428,7 @@ struct super_block { #else struct list_head s_files; #endif + struct list_head s_mounts; /* list of mounts; _not_ for fs use */ /* s_dentry_lru, s_nr_dentry_unused protected by dcache.c lru locks */ struct list_head s_dentry_lru; /* unused dentry lru */ int s_nr_dentry_unused; /* # of dentry on lru */ |
