nfsd4: add a client info file

Add a new nfsd/clients/#/info file with some basic information about
each NFSv4 client.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 8f9747d8452515720e77aeb1471dd9a3e89cc645..a6c722dc7e5e66394511926eb599f45469a66c7f 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -2214,6 +2214,41 @@ find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
        return s;
 }
 
+static int client_info_show(struct seq_file *m, void *v)
+{
+       struct inode *inode = m->private;
+       struct nfsdfs_client *nc;
+       struct nfs4_client *clp;
+       u64 clid;
+
+       nc = get_nfsdfs_client(inode);
+       if (!nc)
+               return -ENXIO;
+       clp = container_of(nc, struct nfs4_client, cl_nfsdfs);
+       memcpy(&clid, &clp->cl_clientid, sizeof(clid));
+       seq_printf(m, "clientid: 0x%llx\n", clid);
+       drop_client(clp);
+
+       return 0;
+}
+
+static int client_info_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, client_info_show, inode);
+}
+
+static const struct file_operations client_info_fops = {
+       .open           = client_info_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+static const struct tree_descr client_files[] = {
+       [0] = {"info", &client_info_fops, S_IRUSR},
+       [1] = {""},
+};
+
 static struct nfs4_client *create_client(struct xdr_netobj name,
                struct svc_rqst *rqstp, nfs4_verifier *verf)
 {
@@ -2242,7 +2277,8 @@ static struct nfs4_client *create_client(struct xdr_netobj name,
        clp->cl_cb_session = NULL;
        clp->net = net;
        clp->cl_nfsd_dentry = nfsd_client_mkdir(nn, &clp->cl_nfsdfs,
-                       clp->cl_clientid.cl_id - nn->clientid_base);
+                       clp->cl_clientid.cl_id - nn->clientid_base,
+                       client_files);
        if (!clp->cl_nfsd_dentry) {
                free_client(clp);
                return NULL;

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 599d600f0658baab5fdf541ad57c8bb7079879e1..4683ba5c69c7e4e97d8c5da9bd83ea3510458b5f 100644 (file)
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -1208,14 +1208,116 @@ out_err:
        goto out;
 }
 
+static void clear_ncl(struct inode *inode)
+{
+       struct nfsdfs_client *ncl = inode->i_private;
+
+       inode->i_private = NULL;
+       synchronize_rcu();
+       kref_put(&ncl->cl_ref, ncl->cl_release);
+}
+
+
+struct nfsdfs_client *__get_nfsdfs_client(struct inode *inode)
+{
+       struct nfsdfs_client *nc = inode->i_private;
+
+       if (nc)
+               kref_get(&nc->cl_ref);
+       return nc;
+}
+
+struct nfsdfs_client *get_nfsdfs_client(struct inode *inode)
+{
+       struct nfsdfs_client *nc;
+
+       rcu_read_lock();
+       nc = __get_nfsdfs_client(inode);
+       rcu_read_unlock();
+       return nc;
+}
+/* from __rpc_unlink */
+static void nfsdfs_remove_file(struct inode *dir, struct dentry *dentry)
+{
+       int ret;
+
+       clear_ncl(d_inode(dentry));
+       dget(dentry);
+       ret = simple_unlink(dir, dentry);
+       d_delete(dentry);
+       dput(dentry);
+       WARN_ON_ONCE(ret);
+}
+
+static void nfsdfs_remove_files(struct dentry *root)
+{
+       struct dentry *dentry, *tmp;
+
+       list_for_each_entry_safe(dentry, tmp, &root->d_subdirs, d_child) {
+               if (!simple_positive(dentry)) {
+                       WARN_ON_ONCE(1); /* I think this can't happen? */
+                       continue;
+               }
+               nfsdfs_remove_file(d_inode(root), dentry);
+       }
+}
+
+/* XXX: cut'n'paste from simple_fill_super; figure out if we could share
+ * code instead. */
+static  int nfsdfs_create_files(struct dentry *root,
+                                       const struct tree_descr *files)
+{
+       struct inode *dir = d_inode(root);
+       struct inode *inode;
+       struct dentry *dentry;
+       int i;
+
+       inode_lock(dir);
+       for (i = 0; files->name && files->name[0]; i++, files++) {
+               if (!files->name)
+                       continue;
+               dentry = d_alloc_name(root, files->name);
+               if (!dentry)
+                       goto out;
+               inode = nfsd_get_inode(d_inode(root)->i_sb,
+                                       S_IFREG | files->mode);
+               if (!inode) {
+                       dput(dentry);
+                       goto out;
+               }
+               inode->i_fop = files->ops;
+               inode->i_private = __get_nfsdfs_client(dir);
+               d_add(dentry, inode);
+               fsnotify_create(dir, dentry);
+       }
+       inode_unlock(dir);
+       return 0;
+out:
+       nfsdfs_remove_files(root);
+       inode_unlock(dir);
+       return -ENOMEM;
+}
+
 /* on success, returns positive number unique to that client. */
-struct dentry *nfsd_client_mkdir(struct nfsd_net *nn, struct nfsdfs_client *ncl, u32 id)
+struct dentry *nfsd_client_mkdir(struct nfsd_net *nn,
+               struct nfsdfs_client *ncl, u32 id,
+               const struct tree_descr *files)
 {
+       struct dentry *dentry;
        char name[11];
+       int ret;
 
        sprintf(name, "%u", id);
 
-       return nfsd_mkdir(nn->nfsd_client_dir, ncl, name);
+       dentry = nfsd_mkdir(nn->nfsd_client_dir, ncl, name);
+       if (IS_ERR(dentry)) /* XXX: tossing errors? */
+               return NULL;
+       ret = nfsdfs_create_files(dentry, files);
+       if (ret) {
+               nfsd_client_rmdir(dentry);
+               return NULL;
+       }
+       return dentry;
 }
 
 /* Taken from __rpc_rmdir: */
@@ -1223,16 +1325,16 @@ void nfsd_client_rmdir(struct dentry *dentry)
 {
        struct inode *dir = d_inode(dentry->d_parent);
        struct inode *inode = d_inode(dentry);
-       struct nfsdfs_client *ncl = inode->i_private;
        int ret;
 
-       inode->i_private = NULL;
-       synchronize_rcu();
-       kref_put(&ncl->cl_ref, ncl->cl_release);
+       inode_lock(dir);
+       nfsdfs_remove_files(dentry);
+       clear_ncl(inode);
        dget(dentry);
        ret = simple_rmdir(dir, dentry);
        WARN_ON_ONCE(ret);
        d_delete(dentry);
+       inode_unlock(dir);
 }
 
 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 85525dcbf77ddcdef3aab164abbbc2ee2dbfb63d..af2947551e9ce87cf3f8a94564963974e84199b3 100644 (file)
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -92,7 +92,9 @@ struct nfsdfs_client {
        void (*cl_release)(struct kref *kref);
 };
 
-struct dentry *nfsd_client_mkdir(struct nfsd_net *nn, struct nfsdfs_client *ncl, u32 id);
+struct nfsdfs_client *get_nfsdfs_client(struct inode *);
+struct dentry *nfsd_client_mkdir(struct nfsd_net *nn,
+               struct nfsdfs_client *ncl, u32 id, const struct tree_descr *);
 void nfsd_client_rmdir(struct dentry *dentry);
 
 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)