NFS: Add server and volume lists to /proc
Make two new proc files available:
/proc/fs/nfsfs/servers
/proc/fs/nfsfs/volumes
The first lists the servers with which we are currently dealing (struct
nfs_client), and the second lists the volumes we have on those servers (struct
nfs_server).
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index dafba60..27f6478 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -1148,3 +1148,287 @@
dprintk("<-- nfs_clone_server() = error %d\n", error);
return ERR_PTR(error);
}
+
+#ifdef CONFIG_PROC_FS
+static struct proc_dir_entry *proc_fs_nfs;
+
+static int nfs_server_list_open(struct inode *inode, struct file *file);
+static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
+static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
+static void nfs_server_list_stop(struct seq_file *p, void *v);
+static int nfs_server_list_show(struct seq_file *m, void *v);
+
+static struct seq_operations nfs_server_list_ops = {
+ .start = nfs_server_list_start,
+ .next = nfs_server_list_next,
+ .stop = nfs_server_list_stop,
+ .show = nfs_server_list_show,
+};
+
+static struct file_operations nfs_server_list_fops = {
+ .open = nfs_server_list_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int nfs_volume_list_open(struct inode *inode, struct file *file);
+static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
+static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
+static void nfs_volume_list_stop(struct seq_file *p, void *v);
+static int nfs_volume_list_show(struct seq_file *m, void *v);
+
+static struct seq_operations nfs_volume_list_ops = {
+ .start = nfs_volume_list_start,
+ .next = nfs_volume_list_next,
+ .stop = nfs_volume_list_stop,
+ .show = nfs_volume_list_show,
+};
+
+static struct file_operations nfs_volume_list_fops = {
+ .open = nfs_volume_list_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/*
+ * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
+ * we're dealing
+ */
+static int nfs_server_list_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *m;
+ int ret;
+
+ ret = seq_open(file, &nfs_server_list_ops);
+ if (ret < 0)
+ return ret;
+
+ m = file->private_data;
+ m->private = PDE(inode)->data;
+
+ return 0;
+}
+
+/*
+ * set up the iterator to start reading from the server list and return the first item
+ */
+static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
+{
+ struct list_head *_p;
+ loff_t pos = *_pos;
+
+ /* lock the list against modification */
+ spin_lock(&nfs_client_lock);
+
+ /* allow for the header line */
+ if (!pos)
+ return SEQ_START_TOKEN;
+ pos--;
+
+ /* find the n'th element in the list */
+ list_for_each(_p, &nfs_client_list)
+ if (!pos--)
+ break;
+
+ return _p != &nfs_client_list ? _p : NULL;
+}
+
+/*
+ * move to next server
+ */
+static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
+{
+ struct list_head *_p;
+
+ (*pos)++;
+
+ _p = v;
+ _p = (v == SEQ_START_TOKEN) ? nfs_client_list.next : _p->next;
+
+ return _p != &nfs_client_list ? _p : NULL;
+}
+
+/*
+ * clean up after reading from the transports list
+ */
+static void nfs_server_list_stop(struct seq_file *p, void *v)
+{
+ spin_unlock(&nfs_client_lock);
+}
+
+/*
+ * display a header line followed by a load of call lines
+ */
+static int nfs_server_list_show(struct seq_file *m, void *v)
+{
+ struct nfs_client *clp;
+
+ /* display header on line 1 */
+ if (v == SEQ_START_TOKEN) {
+ seq_puts(m, "NV SERVER PORT USE HOSTNAME\n");
+ return 0;
+ }
+
+ /* display one transport per line on subsequent lines */
+ clp = list_entry(v, struct nfs_client, cl_share_link);
+
+ seq_printf(m, "v%d %02x%02x%02x%02x %4hx %3d %s\n",
+ clp->cl_nfsversion,
+ NIPQUAD(clp->cl_addr.sin_addr),
+ ntohs(clp->cl_addr.sin_port),
+ atomic_read(&clp->cl_count),
+ clp->cl_hostname);
+
+ return 0;
+}
+
+/*
+ * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
+ */
+static int nfs_volume_list_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *m;
+ int ret;
+
+ ret = seq_open(file, &nfs_volume_list_ops);
+ if (ret < 0)
+ return ret;
+
+ m = file->private_data;
+ m->private = PDE(inode)->data;
+
+ return 0;
+}
+
+/*
+ * set up the iterator to start reading from the volume list and return the first item
+ */
+static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
+{
+ struct list_head *_p;
+ loff_t pos = *_pos;
+
+ /* lock the list against modification */
+ spin_lock(&nfs_client_lock);
+
+ /* allow for the header line */
+ if (!pos)
+ return SEQ_START_TOKEN;
+ pos--;
+
+ /* find the n'th element in the list */
+ list_for_each(_p, &nfs_volume_list)
+ if (!pos--)
+ break;
+
+ return _p != &nfs_volume_list ? _p : NULL;
+}
+
+/*
+ * move to next volume
+ */
+static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
+{
+ struct list_head *_p;
+
+ (*pos)++;
+
+ _p = v;
+ _p = (v == SEQ_START_TOKEN) ? nfs_volume_list.next : _p->next;
+
+ return _p != &nfs_volume_list ? _p : NULL;
+}
+
+/*
+ * clean up after reading from the transports list
+ */
+static void nfs_volume_list_stop(struct seq_file *p, void *v)
+{
+ spin_unlock(&nfs_client_lock);
+}
+
+/*
+ * display a header line followed by a load of call lines
+ */
+static int nfs_volume_list_show(struct seq_file *m, void *v)
+{
+ struct nfs_server *server;
+ struct nfs_client *clp;
+ char dev[8], fsid[17];
+
+ /* display header on line 1 */
+ if (v == SEQ_START_TOKEN) {
+ seq_puts(m, "NV SERVER PORT DEV FSID\n");
+ return 0;
+ }
+ /* display one transport per line on subsequent lines */
+ server = list_entry(v, struct nfs_server, master_link);
+ clp = server->nfs_client;
+
+ snprintf(dev, 8, "%u:%u",
+ MAJOR(server->s_dev), MINOR(server->s_dev));
+
+ snprintf(fsid, 17, "%llx:%llx",
+ server->fsid.major, server->fsid.minor);
+
+ seq_printf(m, "v%d %02x%02x%02x%02x %4hx %-7s %-17s\n",
+ clp->cl_nfsversion,
+ NIPQUAD(clp->cl_addr.sin_addr),
+ ntohs(clp->cl_addr.sin_port),
+ dev,
+ fsid);
+
+ return 0;
+}
+
+/*
+ * initialise the /proc/fs/nfsfs/ directory
+ */
+int __init nfs_fs_proc_init(void)
+{
+ struct proc_dir_entry *p;
+
+ proc_fs_nfs = proc_mkdir("nfsfs", proc_root_fs);
+ if (!proc_fs_nfs)
+ goto error_0;
+
+ proc_fs_nfs->owner = THIS_MODULE;
+
+ /* a file of servers with which we're dealing */
+ p = create_proc_entry("servers", S_IFREG|S_IRUGO, proc_fs_nfs);
+ if (!p)
+ goto error_1;
+
+ p->proc_fops = &nfs_server_list_fops;
+ p->owner = THIS_MODULE;
+
+ /* a file of volumes that we have mounted */
+ p = create_proc_entry("volumes", S_IFREG|S_IRUGO, proc_fs_nfs);
+ if (!p)
+ goto error_2;
+
+ p->proc_fops = &nfs_volume_list_fops;
+ p->owner = THIS_MODULE;
+ return 0;
+
+error_2:
+ remove_proc_entry("servers", proc_fs_nfs);
+error_1:
+ remove_proc_entry("nfsfs", proc_root_fs);
+error_0:
+ return -ENOMEM;
+}
+
+/*
+ * clean up the /proc/fs/nfsfs/ directory
+ */
+void nfs_fs_proc_exit(void)
+{
+ remove_proc_entry("volumes", proc_fs_nfs);
+ remove_proc_entry("servers", proc_fs_nfs);
+ remove_proc_entry("nfsfs", proc_root_fs);
+}
+
+#endif /* CONFIG_PROC_FS */
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index a547c58..cb5c65f 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1141,6 +1141,10 @@
{
int err;
+ err = nfs_fs_proc_init();
+ if (err)
+ goto out5;
+
err = nfs_init_nfspagecache();
if (err)
goto out4;
@@ -1181,6 +1185,8 @@
out3:
nfs_destroy_nfspagecache();
out4:
+ nfs_fs_proc_exit();
+out5:
return err;
}
@@ -1195,6 +1201,7 @@
rpc_proc_unregister("nfs");
#endif
unregister_nfs_fs();
+ nfs_fs_proc_exit();
}
/* Not quite true; I just maintain it */
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index e73ba4f..bea0b01 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -47,6 +47,18 @@
extern struct nfs_server *nfs_clone_server(struct nfs_server *,
struct nfs_fh *,
struct nfs_fattr *);
+#ifdef CONFIG_PROC_FS
+extern int __init nfs_fs_proc_init(void);
+extern void nfs_fs_proc_exit(void);
+#else
+static inline int nfs_fs_proc_init(void)
+{
+ return 0;
+}
+static inline void nfs_fs_proc_exit(void)
+{
+}
+#endif
/* nfs4namespace.c */
#ifdef CONFIG_NFS_V4