8 files changed, 276 insertions, 65 deletions

diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index e9d293593e52..4e321f7353fa 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -46,9 +46,9 @@ struct bin_buffer {
 };
 
 static int
-fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
+fill_read(struct file *file, char *buffer, loff_t off, size_t count)
 {
-        struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+        struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
         struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
         struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
         int rc;
@@ -59,7 +59,7 @@ fill_read(struct dentry *dentry, char *buffer, loff_t off, size_t count)
 
         rc = -EIO;
         if (attr->read)
-                rc = attr->read(kobj, attr, buffer, off, count);
+                rc = attr->read(file, kobj, attr, buffer, off, count);
 
         sysfs_put_active(attr_sd);
 
@@ -70,8 +70,7 @@ static ssize_t
 read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
 {
         struct bin_buffer *bb = file->private_data;
-        struct dentry *dentry = file->f_path.dentry;
-        int size = dentry->d_inode->i_size;
+        int size = file->f_path.dentry->d_inode->i_size;
         loff_t offs = *off;
         int count = min_t(size_t, bytes, PAGE_SIZE);
         char *temp;
@@ -92,7 +91,7 @@ read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
 
         mutex_lock(&bb->mutex);
 
-        count = fill_read(dentry, bb->buffer, offs, count);
+        count = fill_read(file, bb->buffer, offs, count);
         if (count < 0) {
                 mutex_unlock(&bb->mutex);
                 goto out_free;
@@ -117,9 +116,9 @@ read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
 }
 
 static int
-flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
+flush_write(struct file *file, char *buffer, loff_t offset, size_t count)
 {
-        struct sysfs_dirent *attr_sd = dentry->d_fsdata;
+        struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
         struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
         struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
         int rc;
@@ -130,7 +129,7 @@ flush_write(struct dentry *dentry, char *buffer, loff_t offset, size_t count)
 
         rc = -EIO;
         if (attr->write)
-                rc = attr->write(kobj, attr, buffer, offset, count);
+                rc = attr->write(file, kobj, attr, buffer, offset, count);
 
         sysfs_put_active(attr_sd);
 
@@ -141,8 +140,7 @@ static ssize_t write(struct file *file, const char __user *userbuf,
                      size_t bytes, loff_t *off)
 {
         struct bin_buffer *bb = file->private_data;
-        struct dentry *dentry = file->f_path.dentry;
-        int size = dentry->d_inode->i_size;
+        int size = file->f_path.dentry->d_inode->i_size;
         loff_t offs = *off;
         int count = min_t(size_t, bytes, PAGE_SIZE);
         char *temp;
@@ -165,7 +163,7 @@ static ssize_t write(struct file *file, const char __user *userbuf,
 
         memcpy(bb->buffer, temp, count);
 
-        count = flush_write(dentry, bb->buffer, offs, count);
+        count = flush_write(file, bb->buffer, offs, count);
         mutex_unlock(&bb->mutex);
 
         if (count > 0)
@@ -363,7 +361,7 @@ static int mmap(struct file *file, struct vm_area_struct *vma)
         if (!attr->mmap)
                 goto out_put;
 
-        rc = attr->mmap(kobj, attr, vma);
+        rc = attr->mmap(file, kobj, attr, vma);
         if (rc)
                 goto out_put;
 
@@ -501,7 +499,7 @@ int sysfs_create_bin_file(struct kobject *kobj,
 void sysfs_remove_bin_file(struct kobject *kobj,
                            const struct bin_attribute *attr)
 {
-        sysfs_hash_and_remove(kobj->sd, attr->attr.name);
+        sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
 }
 
 EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 590717861c7a..7e54bac8c4b0 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -380,7 +380,7 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
 {
         struct sysfs_inode_attrs *ps_iattr;
 
-        if (sysfs_find_dirent(acxt->parent_sd, sd->s_name))
+        if (sysfs_find_dirent(acxt->parent_sd, sd->s_ns, sd->s_name))
                 return -EEXIST;
 
         sd->s_parent = sysfs_get(acxt->parent_sd);
@@ -533,13 +533,17 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
  *      Pointer to sysfs_dirent if found, NULL if not.
  */
 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
+                                       const void *ns,
                                        const unsigned char *name)
 {
         struct sysfs_dirent *sd;
 
-        for (sd = parent_sd->s_dir.children; sd; sd = sd->s_sibling)
+        for (sd = parent_sd->s_dir.children; sd; sd = sd->s_sibling) {
+                if (ns && sd->s_ns && (sd->s_ns != ns))
+                        continue;
                 if (!strcmp(sd->s_name, name))
                         return sd;
+        }
         return NULL;
 }
 
@@ -558,12 +562,13 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
  *      Pointer to sysfs_dirent if found, NULL if not.
  */
 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
+                                      const void *ns,
                                       const unsigned char *name)
 {
         struct sysfs_dirent *sd;
 
         mutex_lock(&sysfs_mutex);
-        sd = sysfs_find_dirent(parent_sd, name);
+        sd = sysfs_find_dirent(parent_sd, ns, name);
         sysfs_get(sd);
         mutex_unlock(&sysfs_mutex);
 
@@ -572,7 +577,8 @@ struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 EXPORT_SYMBOL_GPL(sysfs_get_dirent);
 
 static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
-                      const char *name, struct sysfs_dirent **p_sd)
+        enum kobj_ns_type type, const void *ns, const char *name,
+        struct sysfs_dirent **p_sd)
 {
         umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
         struct sysfs_addrm_cxt acxt;
@@ -583,6 +589,9 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
         sd = sysfs_new_dirent(name, mode, SYSFS_DIR);
         if (!sd)
                 return -ENOMEM;
+
+        sd->s_flags |= (type << SYSFS_NS_TYPE_SHIFT);
+        sd->s_ns = ns;
         sd->s_dir.kobj = kobj;
 
         /* link in */
@@ -601,7 +610,33 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd,
 int sysfs_create_subdir(struct kobject *kobj, const char *name,
                         struct sysfs_dirent **p_sd)
 {
-        return create_dir(kobj, kobj->sd, name, p_sd);
+        return create_dir(kobj, kobj->sd,
+                          KOBJ_NS_TYPE_NONE, NULL, name, p_sd);
+}
+
+/**
+ *      sysfs_read_ns_type: return associated ns_type
+ *      @kobj: the kobject being queried
+ *
+ *      Each kobject can be tagged with exactly one namespace type
+ *      (i.e. network or user).  Return the ns_type associated with
+ *      this object if any
+ */
+static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj)
+{
+        const struct kobj_ns_type_operations *ops;
+        enum kobj_ns_type type;
+
+        ops = kobj_child_ns_ops(kobj);
+        if (!ops)
+                return KOBJ_NS_TYPE_NONE;
+
+        type = ops->type;
+        BUG_ON(type <= KOBJ_NS_TYPE_NONE);
+        BUG_ON(type >= KOBJ_NS_TYPES);
+        BUG_ON(!kobj_ns_type_registered(type));
+
+        return type;
 }
 
 /**
@@ -610,7 +645,9 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name,
  */
 int sysfs_create_dir(struct kobject * kobj)
 {
+        enum kobj_ns_type type;
         struct sysfs_dirent *parent_sd, *sd;
+        const void *ns = NULL;
         int error = 0;
 
         BUG_ON(!kobj);
@@ -620,7 +657,11 @@ int sysfs_create_dir(struct kobject * kobj)
         else
                 parent_sd = &sysfs_root;
 
-        error = create_dir(kobj, parent_sd, kobject_name(kobj), &sd);
+        if (sysfs_ns_type(parent_sd))
+                ns = kobj->ktype->namespace(kobj);
+        type = sysfs_read_ns_type(kobj);
+
+        error = create_dir(kobj, parent_sd, type, ns, kobject_name(kobj), &sd);
         if (!error)
                 kobj->sd = sd;
         return error;
@@ -630,13 +671,19 @@ static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
                                 struct nameidata *nd)
 {
         struct dentry *ret = NULL;
-        struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata;
+        struct dentry *parent = dentry->d_parent;
+        struct sysfs_dirent *parent_sd = parent->d_fsdata;
         struct sysfs_dirent *sd;
         struct inode *inode;
+        enum kobj_ns_type type;
+        const void *ns;
 
         mutex_lock(&sysfs_mutex);
 
-        sd = sysfs_find_dirent(parent_sd, dentry->d_name.name);
+        type = sysfs_ns_type(parent_sd);
+        ns = sysfs_info(dir->i_sb)->ns[type];
+
+        sd = sysfs_find_dirent(parent_sd, ns, dentry->d_name.name);
 
         /* no such entry */
         if (!sd) {
@@ -735,7 +782,8 @@ void sysfs_remove_dir(struct kobject * kobj)
 }
 
 int sysfs_rename(struct sysfs_dirent *sd,
-        struct sysfs_dirent *new_parent_sd, const char *new_name)
+        struct sysfs_dirent *new_parent_sd, const void *new_ns,
+        const char *new_name)
 {
         const char *dup_name = NULL;
         int error;
@@ -743,12 +791,12 @@ int sysfs_rename(struct sysfs_dirent *sd,
         mutex_lock(&sysfs_mutex);
 
         error = 0;
-        if ((sd->s_parent == new_parent_sd) &&
+        if ((sd->s_parent == new_parent_sd) && (sd->s_ns == new_ns) &&
             (strcmp(sd->s_name, new_name) == 0))
                 goto out;       /* nothing to rename */
 
         error = -EEXIST;
-        if (sysfs_find_dirent(new_parent_sd, new_name))
+        if (sysfs_find_dirent(new_parent_sd, new_ns, new_name))
                 goto out;
 
         /* rename sysfs_dirent */
@@ -770,6 +818,7 @@ int sysfs_rename(struct sysfs_dirent *sd,
                 sd->s_parent = new_parent_sd;
                 sysfs_link_sibling(sd);
         }
+        sd->s_ns = new_ns;
 
         error = 0;
  out:
@@ -780,19 +829,28 @@ int sysfs_rename(struct sysfs_dirent *sd,
 
 int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 {
-        return sysfs_rename(kobj->sd, kobj->sd->s_parent, new_name);
+        struct sysfs_dirent *parent_sd = kobj->sd->s_parent;
+        const void *new_ns = NULL;
+
+        if (sysfs_ns_type(parent_sd))
+                new_ns = kobj->ktype->namespace(kobj);
+
+        return sysfs_rename(kobj->sd, parent_sd, new_ns, new_name);
 }
 
 int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj)
 {
         struct sysfs_dirent *sd = kobj->sd;
         struct sysfs_dirent *new_parent_sd;
+        const void *new_ns = NULL;
 
         BUG_ON(!sd->s_parent);
+        if (sysfs_ns_type(sd->s_parent))
+                new_ns = kobj->ktype->namespace(kobj);
         new_parent_sd = new_parent_kobj && new_parent_kobj->sd ?
                 new_parent_kobj->sd : &sysfs_root;
 
-        return sysfs_rename(sd, new_parent_sd, sd->s_name);
+        return sysfs_rename(sd, new_parent_sd, new_ns, sd->s_name);
 }
 
 /* Relationship between s_mode and the DT_xxx types */
@@ -807,32 +865,35 @@ static int sysfs_dir_release(struct inode *inode, struct file *filp)
         return 0;
 }
 
-static struct sysfs_dirent *sysfs_dir_pos(struct sysfs_dirent *parent_sd,
-        ino_t ino, struct sysfs_dirent *pos)
+static struct sysfs_dirent *sysfs_dir_pos(const void *ns,
+        struct sysfs_dirent *parent_sd, ino_t ino, struct sysfs_dirent *pos)
 {
         if (pos) {
                 int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) &&
                         pos->s_parent == parent_sd &&
                         ino == pos->s_ino;
                 sysfs_put(pos);
-                if (valid)
-                        return pos;
+                if (!valid)
+                        pos = NULL;
         }
-        pos = NULL;
-        if ((ino > 1) && (ino < INT_MAX)) {
+        if (!pos && (ino > 1) && (ino < INT_MAX)) {
                 pos = parent_sd->s_dir.children;
                 while (pos && (ino > pos->s_ino))
                         pos = pos->s_sibling;
         }
+        while (pos && pos->s_ns && pos->s_ns != ns)
+                pos = pos->s_sibling;
         return pos;
 }
 
-static struct sysfs_dirent *sysfs_dir_next_pos(struct sysfs_dirent *parent_sd,
-        ino_t ino, struct sysfs_dirent *pos)
+static struct sysfs_dirent *sysfs_dir_next_pos(const void *ns,
+        struct sysfs_dirent *parent_sd, ino_t ino, struct sysfs_dirent *pos)
 {
-        pos = sysfs_dir_pos(parent_sd, ino, pos);
+        pos = sysfs_dir_pos(ns, parent_sd, ino, pos);
         if (pos)
                 pos = pos->s_sibling;
+        while (pos && pos->s_ns && pos->s_ns != ns)
+                pos = pos->s_sibling;
         return pos;
 }
 
@@ -841,8 +902,13 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
         struct dentry *dentry = filp->f_path.dentry;
         struct sysfs_dirent * parent_sd = dentry->d_fsdata;
         struct sysfs_dirent *pos = filp->private_data;
+        enum kobj_ns_type type;
+        const void *ns;
         ino_t ino;
 
+        type = sysfs_ns_type(parent_sd);
+        ns = sysfs_info(dentry->d_sb)->ns[type];
+
         if (filp->f_pos == 0) {
                 ino = parent_sd->s_ino;
                 if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) == 0)
@@ -857,9 +923,9 @@ static int sysfs_readdir(struct file * filp, void * dirent, filldir_t filldir)
                         filp->f_pos++;
         }
         mutex_lock(&sysfs_mutex);
-        for (pos = sysfs_dir_pos(parent_sd, filp->f_pos, pos);
+        for (pos = sysfs_dir_pos(ns, parent_sd, filp->f_pos, pos);
              pos;
-             pos = sysfs_dir_next_pos(parent_sd, filp->f_pos, pos)) {
+             pos = sysfs_dir_next_pos(ns, parent_sd, filp->f_pos, pos)) {
                 const char * name;
                 unsigned int type;
                 int len, ret;
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index e222b2582746..1beaa739d0a6 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -478,9 +478,12 @@ void sysfs_notify(struct kobject *k, const char *dir, const char *attr)
         mutex_lock(&sysfs_mutex);
 
         if (sd && dir)
-                sd = sysfs_find_dirent(sd, dir);
+                /* Only directories are tagged, so no need to pass
+                 * a tag explicitly.
+                 */
+                sd = sysfs_find_dirent(sd, NULL, dir);
         if (sd && attr)
-                sd = sysfs_find_dirent(sd, attr);
+                sd = sysfs_find_dirent(sd, NULL, attr);
         if (sd)
                 sysfs_notify_dirent(sd);
 
@@ -569,7 +572,7 @@ int sysfs_add_file_to_group(struct kobject *kobj,
         int error;
 
         if (group)
-                dir_sd = sysfs_get_dirent(kobj->sd, group);
+                dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
         else
                 dir_sd = sysfs_get(kobj->sd);
 
@@ -599,7 +602,7 @@ int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode)
         mutex_lock(&sysfs_mutex);
 
         rc = -ENOENT;
-        sd = sysfs_find_dirent(kobj->sd, attr->name);
+        sd = sysfs_find_dirent(kobj->sd, NULL, attr->name);
         if (!sd)
                 goto out;
 
@@ -624,7 +627,7 @@ EXPORT_SYMBOL_GPL(sysfs_chmod_file);
 
 void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
 {
-        sysfs_hash_and_remove(kobj->sd, attr->name);
+        sysfs_hash_and_remove(kobj->sd, NULL, attr->name);
 }
 
 void sysfs_remove_files(struct kobject * kobj, const struct attribute **ptr)
@@ -646,11 +649,11 @@ void sysfs_remove_file_from_group(struct kobject *kobj,
         struct sysfs_dirent *dir_sd;
 
         if (group)
-                dir_sd = sysfs_get_dirent(kobj->sd, group);
+                dir_sd = sysfs_get_dirent(kobj->sd, NULL, group);
         else
                 dir_sd = sysfs_get(kobj->sd);
         if (dir_sd) {
-                sysfs_hash_and_remove(dir_sd, attr->name);
+                sysfs_hash_and_remove(dir_sd, NULL, attr->name);
                 sysfs_put(dir_sd);
         }
 }
diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c
index fe611949a7f7..23c1e598792a 100644
--- a/fs/sysfs/group.c
+++ b/fs/sysfs/group.c
@@ -23,7 +23,7 @@ static void remove_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
         int i;
 
         for (i = 0, attr = grp->attrs; *attr; i++, attr++)
-                sysfs_hash_and_remove(dir_sd, (*attr)->name);
+                sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name);
 }
 
 static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
@@ -39,7 +39,7 @@ static int create_files(struct sysfs_dirent *dir_sd, struct kobject *kobj,
                  * visibility.  Do this by first removing then
                  * re-adding (if required) the file */
                 if (update)
-                        sysfs_hash_and_remove(dir_sd, (*attr)->name);
+                        sysfs_hash_and_remove(dir_sd, NULL, (*attr)->name);
                 if (grp->is_visible) {
                         mode = grp->is_visible(kobj, *attr, i);
                         if (!mode)
@@ -132,7 +132,7 @@ void sysfs_remove_group(struct kobject * kobj,
         struct sysfs_dirent *sd;
 
         if (grp->name) {
-                sd = sysfs_get_dirent(dir_sd, grp->name);
+                sd = sysfs_get_dirent(dir_sd, NULL, grp->name);
                 if (!sd) {
                         WARN(!sd, KERN_WARNING "sysfs group %p not found for "
                                 "kobject '%s'\n", grp, kobject_name(kobj));
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index a4a0a9419711..bde1a4c3679a 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -117,13 +117,11 @@ int sysfs_setattr(struct dentry *dentry, struct iattr *iattr)
         if (error)
                 goto out;
 
-        iattr->ia_valid &= ~ATTR_SIZE; /* ignore size changes */
-
-        error = inode_setattr(inode, iattr);
-        if (error)
-                goto out;
+        /* this ignores size changes */
+        generic_setattr(inode, iattr);
 
         error = sysfs_sd_setattr(sd, iattr);
+
 out:
         mutex_unlock(&sysfs_mutex);
         return error;
@@ -324,7 +322,7 @@ void sysfs_delete_inode(struct inode *inode)
         sysfs_put(sd);
 }
 
-int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
+int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name)
 {
         struct sysfs_addrm_cxt acxt;
         struct sysfs_dirent *sd;
@@ -334,7 +332,9 @@ int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
 
         sysfs_addrm_start(&acxt, dir_sd);
 
-        sd = sysfs_find_dirent(dir_sd, name);
+        sd = sysfs_find_dirent(dir_sd, ns, name);
+        if (sd && (sd->s_ns != ns))
+                sd = NULL;
         if (sd)
                 sysfs_remove_one(&acxt, sd);
 
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index 776137828dca..281c0c9bc39f 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -35,7 +35,7 @@ static const struct super_operations sysfs_ops = {
 struct sysfs_dirent sysfs_root = {
         .s_name         = "",
         .s_count        = ATOMIC_INIT(1),
-        .s_flags        = SYSFS_DIR,
+        .s_flags        = SYSFS_DIR | (KOBJ_NS_TYPE_NONE << SYSFS_NS_TYPE_SHIFT),
         .s_mode         = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO,
         .s_ino          = 1,
 };
@@ -72,18 +72,107 @@ static int sysfs_fill_super(struct super_block *sb, void *data, int silent)
         return 0;
 }
 
+static int sysfs_test_super(struct super_block *sb, void *data)
+{
+        struct sysfs_super_info *sb_info = sysfs_info(sb);
+        struct sysfs_super_info *info = data;
+        enum kobj_ns_type type;
+        int found = 1;
+
+        for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) {
+                if (sb_info->ns[type] != info->ns[type])
+                        found = 0;
+        }
+        return found;
+}
+
+static int sysfs_set_super(struct super_block *sb, void *data)
+{
+        int error;
+        error = set_anon_super(sb, data);
+        if (!error)
+                sb->s_fs_info = data;
+        return error;
+}
+
 static int sysfs_get_sb(struct file_system_type *fs_type,
         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 {
-        return get_sb_single(fs_type, flags, data, sysfs_fill_super, mnt);
+        struct sysfs_super_info *info;
+        enum kobj_ns_type type;
+        struct super_block *sb;
+        int error;
+
+        error = -ENOMEM;
+        info = kzalloc(sizeof(*info), GFP_KERNEL);
+        if (!info)
+                goto out;
+
+        for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++)
+                info->ns[type] = kobj_ns_current(type);
+
+        sb = sget(fs_type, sysfs_test_super, sysfs_set_super, info);
+        if (IS_ERR(sb) || sb->s_fs_info != info)
+                kfree(info);
+        if (IS_ERR(sb)) {
+                error = PTR_ERR(sb);
+                goto out;
+        }
+        if (!sb->s_root) {
+                sb->s_flags = flags;
+                error = sysfs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
+                if (error) {
+                        deactivate_locked_super(sb);
+                        goto out;
+                }
+                sb->s_flags |= MS_ACTIVE;
+        }
+
+        simple_set_mnt(mnt, sb);
+        error = 0;
+out:
+        return error;
+}
+
+static void sysfs_kill_sb(struct super_block *sb)
+{
+        struct sysfs_super_info *info = sysfs_info(sb);
+
+        /* Remove the superblock from fs_supers/s_instances
+         * so we can't find it, before freeing sysfs_super_info.
+         */
+        kill_anon_super(sb);
+        kfree(info);
 }
 
 static struct file_system_type sysfs_fs_type = {
         .name           = "sysfs",
         .get_sb         = sysfs_get_sb,
-        .kill_sb        = kill_anon_super,
+        .kill_sb        = sysfs_kill_sb,
 };
 
+void sysfs_exit_ns(enum kobj_ns_type type, const void *ns)
+{
+        struct super_block *sb;
+
+        mutex_lock(&sysfs_mutex);
+        spin_lock(&sb_lock);
+        list_for_each_entry(sb, &sysfs_fs_type.fs_supers, s_instances) {
+                struct sysfs_super_info *info = sysfs_info(sb);
+                /*
+                 * If we see a superblock on the fs_supers/s_instances
+                 * list the unmount has not completed and sb->s_fs_info
+                 * points to a valid struct sysfs_super_info.
+                 */
+                /* Ignore superblocks with the wrong ns */
+                if (info->ns[type] != ns)
+                        continue;
+                info->ns[type] = NULL;
+        }
+        spin_unlock(&sb_lock);
+        mutex_unlock(&sysfs_mutex);
+}
+
 int __init sysfs_init(void)
 {
         int err = -ENOMEM;
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 942f239a2132..f71246bebfe4 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -58,6 +58,8 @@ static int sysfs_do_create_link(struct kobject *kobj, struct kobject *target,
         if (!sd)
                 goto out_put;
 
+        if (sysfs_ns_type(parent_sd))
+                sd->s_ns = target->ktype->namespace(target);
         sd->s_symlink.target_sd = target_sd;
         target_sd = NULL;       /* reference is now owned by the symlink */
 
@@ -107,6 +109,26 @@ int sysfs_create_link_nowarn(struct kobject *kobj, struct kobject *target,
 }
 
 /**
+ *      sysfs_delete_link - remove symlink in object's directory.
+ *      @kobj:  object we're acting for.
+ *      @targ:  object we're pointing to.
+ *      @name:  name of the symlink to remove.
+ *
+ *      Unlike sysfs_remove_link sysfs_delete_link has enough information
+ *      to successfully delete symlinks in tagged directories.
+ */
+void sysfs_delete_link(struct kobject *kobj, struct kobject *targ,
+                        const char *name)
+{
+        const void *ns = NULL;
+        spin_lock(&sysfs_assoc_lock);
+        if (targ->sd)
+                ns = targ->sd->s_ns;
+        spin_unlock(&sysfs_assoc_lock);
+        sysfs_hash_and_remove(kobj->sd, ns, name);
+}
+
+/**
  *      sysfs_remove_link - remove symlink in object's directory.
  *      @kobj:  object we're acting for.
  *      @name:  name of the symlink to remove.
@@ -121,7 +143,7 @@ void sysfs_remove_link(struct kobject * kobj, const char * name)
         else
                 parent_sd = kobj->sd;
 
-        sysfs_hash_and_remove(parent_sd, name);
+        sysfs_hash_and_remove(parent_sd, NULL, name);
 }
 
 /**
@@ -137,6 +159,7 @@ int sysfs_rename_link(struct kobject *kobj, struct kobject *targ,
                         const char *old, const char *new)
 {
         struct sysfs_dirent *parent_sd, *sd = NULL;
+        const void *old_ns = NULL, *new_ns = NULL;
         int result;
 
         if (!kobj)
@@ -144,8 +167,11 @@ int sysfs_rename_link(struct kobject *kobj, struct kobject *targ,
         else
                 parent_sd = kobj->sd;
 
+        if (targ->sd)
+                old_ns = targ->sd->s_ns;
+
         result = -ENOENT;
-        sd = sysfs_get_dirent(parent_sd, old);
+        sd = sysfs_get_dirent(parent_sd, old_ns, old);
         if (!sd)
                 goto out;
 
@@ -155,7 +181,10 @@ int sysfs_rename_link(struct kobject *kobj, struct kobject *targ,
         if (sd->s_symlink.target_sd->s_dir.kobj != targ)
                 goto out;
 
-        result = sysfs_rename(sd, parent_sd, new);
+        if (sysfs_ns_type(parent_sd))
+                new_ns = targ->ktype->namespace(targ);
+
+        result = sysfs_rename(sd, parent_sd, new_ns, new);
 
 out:
         sysfs_put(sd);
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 30f5a44fb5d3..6a13105b5594 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -58,6 +58,7 @@ struct sysfs_dirent {
         struct sysfs_dirent     *s_sibling;
         const char              *s_name;
 
+        const void              *s_ns; /* namespace tag */
         union {
                 struct sysfs_elem_dir           s_dir;
                 struct sysfs_elem_symlink       s_symlink;
@@ -81,14 +82,27 @@ struct sysfs_dirent {
 #define SYSFS_COPY_NAME                 (SYSFS_DIR | SYSFS_KOBJ_LINK)
 #define SYSFS_ACTIVE_REF                (SYSFS_KOBJ_ATTR | SYSFS_KOBJ_BIN_ATTR)
 
-#define SYSFS_FLAG_MASK                 ~SYSFS_TYPE_MASK
-#define SYSFS_FLAG_REMOVED              0x0200
+/* identify any namespace tag on sysfs_dirents */
+#define SYSFS_NS_TYPE_MASK              0xff00
+#define SYSFS_NS_TYPE_SHIFT             8
+
+#define SYSFS_FLAG_MASK                 ~(SYSFS_NS_TYPE_MASK|SYSFS_TYPE_MASK)
+#define SYSFS_FLAG_REMOVED              0x020000
 
 static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
 {
         return sd->s_flags & SYSFS_TYPE_MASK;
 }
 
+/*
+ * Return any namespace tags on this dirent.
+ * enum kobj_ns_type is defined in linux/kobject.h
+ */
+static inline enum kobj_ns_type sysfs_ns_type(struct sysfs_dirent *sd)
+{
+        return (sd->s_flags & SYSFS_NS_TYPE_MASK) >> SYSFS_NS_TYPE_SHIFT;
+}
+
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 #define sysfs_dirent_init_lockdep(sd)                           \
 do {                                                            \
@@ -114,6 +128,16 @@ struct sysfs_addrm_cxt {
 /*
  * mount.c
  */
+
+/*
+ * Each sb is associated with a set of namespace tags (i.e.
+ * the network namespace of the task which mounted this sysfs
+ * instance).
+ */
+struct sysfs_super_info {
+        const void *ns[KOBJ_NS_TYPES];
+};
+#define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info))
 extern struct sysfs_dirent sysfs_root;
 extern struct kmem_cache *sysfs_dir_cachep;
 
@@ -137,8 +161,10 @@ void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd);
 void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt);
 
 struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd,
+                                       const void *ns,
                                        const unsigned char *name);
 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
+                                      const void *ns,
                                       const unsigned char *name);
 struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type);
 
@@ -149,7 +175,7 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name,
 void sysfs_remove_subdir(struct sysfs_dirent *sd);
 
 int sysfs_rename(struct sysfs_dirent *sd,
-        struct sysfs_dirent *new_parent_sd, const char *new_name);
+        struct sysfs_dirent *new_parent_sd, const void *ns, const char *new_name);
 
 static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd)
 {
@@ -179,7 +205,7 @@ int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 int sysfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
 int sysfs_setxattr(struct dentry *dentry, const char *name, const void *value,
                 size_t size, int flags);
-int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
+int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const void *ns, const char *name);
 int sysfs_inode_init(void);
 
 /*