Merge branch 'containers'

7 files changed, 242 insertions, 9 deletions

diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index c587e3c4c6a6..34cdeaecccf6 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -8,7 +8,8 @@ obj-$(CONFIG_NFS_FS) += nfs.o
 CFLAGS_nfstrace.o += -I$(src)
 nfs-y                   := client.o dir.o file.o getroot.o inode.o super.o \
                            io.o direct.o pagelist.o read.o symlink.o unlink.o \
-                           write.o namespace.o mount_clnt.o nfstrace.o export.o
+                           write.o namespace.o mount_clnt.o nfstrace.o \
+                           export.o sysfs.o
 nfs-$(CONFIG_ROOT_NFS)  += nfsroot.o
 nfs-$(CONFIG_SYSCTL)    += sysctl.o
 nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index d7e4f0848e28..6e7aeb543f6a 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -49,6 +49,7 @@
 #include "pnfs.h"
 #include "nfs.h"
 #include "netns.h"
+#include "sysfs.h"
 
 #define NFSDBG_FACILITY         NFSDBG_CLIENT
 
@@ -192,7 +193,7 @@ error_0:
 EXPORT_SYMBOL_GPL(nfs_alloc_client);
 
 #if IS_ENABLED(CONFIG_NFS_V4)
-void nfs_cleanup_cb_ident_idr(struct net *net)
+static void nfs_cleanup_cb_ident_idr(struct net *net)
 {
         struct nfs_net *nn = net_generic(net, nfs_net_id);
 
@@ -214,7 +215,7 @@ static void pnfs_init_server(struct nfs_server *server)
 }
 
 #else
-void nfs_cleanup_cb_ident_idr(struct net *net)
+static void nfs_cleanup_cb_ident_idr(struct net *net)
 {
 }
 
@@ -1072,6 +1073,18 @@ void nfs_clients_init(struct net *net)
 #endif
         spin_lock_init(&nn->nfs_client_lock);
         nn->boot_time = ktime_get_real();
+
+        nfs_netns_sysfs_setup(nn, net);
+}
+
+void nfs_clients_exit(struct net *net)
+{
+        struct nfs_net *nn = net_generic(net, nfs_net_id);
+
+        nfs_netns_sysfs_destroy(nn);
+        nfs_cleanup_cb_ident_idr(net);
+        WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
+        WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
 }
 
 #ifdef CONFIG_PROC_FS
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index ea52c71534b5..8a1758200b57 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -51,6 +51,7 @@
 #include "pnfs.h"
 #include "nfs.h"
 #include "netns.h"
+#include "sysfs.h"
 
 #include "nfstrace.h"
 
@@ -2167,12 +2168,8 @@ static int nfs_net_init(struct net *net)
 
 static void nfs_net_exit(struct net *net)
 {
-        struct nfs_net *nn = net_generic(net, nfs_net_id);
-
         nfs_fs_proc_net_exit(net);
-        nfs_cleanup_cb_ident_idr(net);
-        WARN_ON_ONCE(!list_empty(&nn->nfs_client_list));
-        WARN_ON_ONCE(!list_empty(&nn->nfs_volume_list));
+        nfs_clients_exit(net);
 }
 
 static struct pernet_operations nfs_net_ops = {
@@ -2189,6 +2186,10 @@ static int __init init_nfs_fs(void)
 {
         int err;
 
+        err = nfs_sysfs_init();
+        if (err < 0)
+                goto out10;
+
         err = register_pernet_subsys(&nfs_net_ops);
         if (err < 0)
                 goto out9;
@@ -2252,6 +2253,8 @@ out7:
 out8:
         unregister_pernet_subsys(&nfs_net_ops);
 out9:
+        nfs_sysfs_exit();
+out10:
         return err;
 }
 
@@ -2268,6 +2271,7 @@ static void __exit exit_nfs_fs(void)
         unregister_nfs_fs();
         nfs_fs_proc_exit();
         nfsiod_stop();
+        nfs_sysfs_exit();
 }
 
 /* Not quite true; I just maintain it */
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 498fab72f70b..9e87265907b8 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -158,6 +158,7 @@ extern void nfs_umount(const struct nfs_mount_request *info);
 /* client.c */
 extern const struct rpc_program nfs_program;
 extern void nfs_clients_init(struct net *net);
+extern void nfs_clients_exit(struct net *net);
 extern struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *);
 int nfs_create_rpc_client(struct nfs_client *, const struct nfs_client_initdata *, rpc_authflavor_t);
 struct nfs_client *nfs_get_client(const struct nfs_client_initdata *);
@@ -170,7 +171,6 @@ int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
 struct nfs_server *nfs_alloc_server(void);
 void nfs_server_copy_userdata(struct nfs_server *, struct nfs_server *);
 
-extern void nfs_cleanup_cb_ident_idr(struct net *);
 extern void nfs_put_client(struct nfs_client *);
 extern void nfs_free_client(struct nfs_client *);
 extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h
index fc9978c58265..c8374f74dce1 100644
--- a/fs/nfs/netns.h
+++ b/fs/nfs/netns.h
@@ -15,6 +15,8 @@ struct bl_dev_msg {
         uint32_t major, minor;
 };
 
+struct nfs_netns_client;
+
 struct nfs_net {
         struct cache_detail *nfs_dns_resolve;
         struct rpc_pipe *bl_device_pipe;
@@ -29,6 +31,7 @@ struct nfs_net {
         unsigned short nfs_callback_tcpport6;
         int cb_users[NFS4_MAX_MINOR_VERSION + 1];
 #endif
+        struct nfs_netns_client *nfs_client;
         spinlock_t nfs_client_lock;
         ktime_t boot_time;
 #ifdef CONFIG_PROC_FS
diff --git a/fs/nfs/sysfs.c b/fs/nfs/sysfs.c
new file mode 100644
index 000000000000..4f3390b20239
--- /dev/null
+++ b/fs/nfs/sysfs.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Hammerspace Inc
+ */
+
+#include <linux/module.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/string.h>
+#include <linux/nfs_fs.h>
+#include <linux/rcupdate.h>
+
+#include "nfs4_fs.h"
+#include "netns.h"
+#include "sysfs.h"
+
+struct kobject *nfs_client_kobj;
+static struct kset *nfs_client_kset;
+
+static void nfs_netns_object_release(struct kobject *kobj)
+{
+        kfree(kobj);
+}
+
+static const struct kobj_ns_type_operations *nfs_netns_object_child_ns_type(
+                struct kobject *kobj)
+{
+        return &net_ns_type_operations;
+}
+
+static struct kobj_type nfs_netns_object_type = {
+        .release = nfs_netns_object_release,
+        .sysfs_ops = &kobj_sysfs_ops,
+        .child_ns_type = nfs_netns_object_child_ns_type,
+};
+
+static struct kobject *nfs_netns_object_alloc(const char *name,
+                struct kset *kset, struct kobject *parent)
+{
+        struct kobject *kobj;
+
+        kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
+        if (kobj) {
+                kobj->kset = kset;
+                if (kobject_init_and_add(kobj, &nfs_netns_object_type,
+                                        parent, "%s", name) == 0)
+                        return kobj;
+                kobject_put(kobj);
+        }
+        return NULL;
+}
+
+int nfs_sysfs_init(void)
+{
+        nfs_client_kset = kset_create_and_add("nfs", NULL, fs_kobj);
+        if (!nfs_client_kset)
+                return -ENOMEM;
+        nfs_client_kobj = nfs_netns_object_alloc("net", nfs_client_kset, NULL);
+        if  (!nfs_client_kobj) {
+                kset_unregister(nfs_client_kset);
+                nfs_client_kset = NULL;
+                return -ENOMEM;
+        }
+        return 0;
+}
+
+void nfs_sysfs_exit(void)
+{
+        kobject_put(nfs_client_kobj);
+        kset_unregister(nfs_client_kset);
+}
+
+static ssize_t nfs_netns_identifier_show(struct kobject *kobj,
+                struct kobj_attribute *attr, char *buf)
+{
+        struct nfs_netns_client *c = container_of(kobj,
+                        struct nfs_netns_client,
+                        kobject);
+        return scnprintf(buf, PAGE_SIZE, "%s\n", c->identifier);
+}
+
+/* Strip trailing '\n' */
+static size_t nfs_string_strip(const char *c, size_t len)
+{
+        while (len > 0 && c[len-1] == '\n')
+                --len;
+        return len;
+}
+
+static ssize_t nfs_netns_identifier_store(struct kobject *kobj,
+                struct kobj_attribute *attr,
+                const char *buf, size_t count)
+{
+        struct nfs_netns_client *c = container_of(kobj,
+                        struct nfs_netns_client,
+                        kobject);
+        const char *old;
+        char *p;
+        size_t len;
+
+        len = nfs_string_strip(buf, min_t(size_t, count, CONTAINER_ID_MAXLEN));
+        if (!len)
+                return 0;
+        p = kmemdup_nul(buf, len, GFP_KERNEL);
+        if (!p)
+                return -ENOMEM;
+        old = xchg(&c->identifier, p);
+        if (old) {
+                synchronize_rcu();
+                kfree(old);
+        }
+        return count;
+}
+
+static void nfs_netns_client_release(struct kobject *kobj)
+{
+        struct nfs_netns_client *c = container_of(kobj,
+                        struct nfs_netns_client,
+                        kobject);
+
+        if (c->identifier)
+                kfree(c->identifier);
+        kfree(c);
+}
+
+static const void *nfs_netns_client_namespace(struct kobject *kobj)
+{
+        return container_of(kobj, struct nfs_netns_client, kobject)->net;
+}
+
+static struct kobj_attribute nfs_netns_client_id = __ATTR(identifier,
+                0644, nfs_netns_identifier_show, nfs_netns_identifier_store);
+
+static struct attribute *nfs_netns_client_attrs[] = {
+        &nfs_netns_client_id.attr,
+        NULL,
+};
+
+static struct kobj_type nfs_netns_client_type = {
+        .release = nfs_netns_client_release,
+        .default_attrs = nfs_netns_client_attrs,
+        .sysfs_ops = &kobj_sysfs_ops,
+        .namespace = nfs_netns_client_namespace,
+};
+
+static struct nfs_netns_client *nfs_netns_client_alloc(struct kobject *parent,
+                struct net *net)
+{
+        struct nfs_netns_client *p;
+
+        p = kzalloc(sizeof(*p), GFP_KERNEL);
+        if (p) {
+                p->net = net;
+                p->kobject.kset = nfs_client_kset;
+                if (kobject_init_and_add(&p->kobject, &nfs_netns_client_type,
+                                        parent, "nfs_client") == 0)
+                        return p;
+                kobject_put(&p->kobject);
+        }
+        return NULL;
+}
+
+void nfs_netns_sysfs_setup(struct nfs_net *netns, struct net *net)
+{
+        struct nfs_netns_client *clp;
+
+        clp = nfs_netns_client_alloc(nfs_client_kobj, net);
+        if (clp) {
+                netns->nfs_client = clp;
+                kobject_uevent(&clp->kobject, KOBJ_ADD);
+        }
+}
+
+void nfs_netns_sysfs_destroy(struct nfs_net *netns)
+{
+        struct nfs_netns_client *clp = netns->nfs_client;
+
+        if (clp) {
+                kobject_uevent(&clp->kobject, KOBJ_REMOVE);
+                kobject_del(&clp->kobject);
+                kobject_put(&clp->kobject);
+                netns->nfs_client = NULL;
+        }
+}
diff --git a/fs/nfs/sysfs.h b/fs/nfs/sysfs.h
new file mode 100644
index 000000000000..f1b27411dcc0
--- /dev/null
+++ b/fs/nfs/sysfs.h
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Hammerspace Inc
+ */
+
+#ifndef __NFS_SYSFS_H
+#define __NFS_SYSFS_H
+
+#define CONTAINER_ID_MAXLEN (64)
+
+struct nfs_netns_client {
+        struct kobject kobject;
+        struct net *net;
+        const char *identifier;
+};
+
+extern struct kobject *nfs_client_kobj;
+
+extern int nfs_sysfs_init(void);
+extern void nfs_sysfs_exit(void);
+
+void nfs_netns_sysfs_setup(struct nfs_net *netns, struct net *net);
+void nfs_netns_sysfs_destroy(struct nfs_net *netns);
+
+#endif