[IPoIB] add path record information in debugfs

Add ibX_path files to debugfs that contain information about the IPoIB
path cache.  IPoIB ARP only gives GIDs, which the IPoIB driver must
resolve to real IB paths through the ib_sa module.  For debugging,
when the ARP table looks OK but traffic isn't flowing, it's useful to
be able to see if the resolution from GID to path worked.

Also clean up the formatting of the existing _mcg debugfs files.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 151 insertions, 26 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_fs.c b/drivers/infiniband/ulp/ipoib/ipoib_fs.c
index 38b150f..685258e 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_fs.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_fs.c
@@ -43,6 +43,18 @@ struct file_operations;
 
 static struct dentry *ipoib_root;
 
+static void format_gid(union ib_gid *gid, char *buf)
+{
+	int i, n;
+
+	for (n = 0, i = 0; i < 8; ++i) {
+		n += sprintf(buf + n, "%x",
+			     be16_to_cpu(((__be16 *) gid->raw)[i]));
+		if (i < 7)
+			buf[n++] = ':';
+	}
+}
+
 static void *ipoib_mcg_seq_start(struct seq_file *file, loff_t *pos)
 {
 	struct ipoib_mcast_iter *iter;
@@ -54,7 +66,7 @@ static void *ipoib_mcg_seq_start(struct seq_file *file, loff_t *pos)
 
 	while (n--) {
 		if (ipoib_mcast_iter_next(iter)) {
-			ipoib_mcast_iter_free(iter);
+			kfree(iter);
 			return NULL;
 		}
 	}
@@ -70,7 +82,7 @@ static void *ipoib_mcg_seq_next(struct seq_file *file, void *iter_ptr,
 	(*pos)++;
 
 	if (ipoib_mcast_iter_next(iter)) {
-		ipoib_mcast_iter_free(iter);
+		kfree(iter);
 		return NULL;
 	}
 
@@ -87,32 +99,32 @@ static int ipoib_mcg_seq_show(struct seq_file *file, void *iter_ptr)
 	struct ipoib_mcast_iter *iter = iter_ptr;
 	char gid_buf[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"];
 	union ib_gid mgid;
-	int i, n;
 	unsigned long created;
 	unsigned int queuelen, complete, send_only;
 
-	if (iter) {
-		ipoib_mcast_iter_read(iter, &mgid, &created, &queuelen,
-				      &complete, &send_only);
+	if (!iter)
+		return 0;
 
-		for (n = 0, i = 0; i < sizeof mgid / 2; ++i) {
-			n += sprintf(gid_buf + n, "%x",
-				     be16_to_cpu(((__be16 *) mgid.raw)[i]));
-			if (i < sizeof mgid / 2 - 1)
-				gid_buf[n++] = ':';
-		}
-	}
+	ipoib_mcast_iter_read(iter, &mgid, &created, &queuelen,
+			      &complete, &send_only);
 
-	seq_printf(file, "GID: %*s", -(1 + (int) sizeof gid_buf), gid_buf);
+	format_gid(&mgid, gid_buf);
 
 	seq_printf(file,
-		   " created: %10ld queuelen: %4d complete: %d send_only: %d\n",
-		   created, queuelen, complete, send_only);
+		   "GID: %s\n"
+		   "  created: %10ld\n"
+		   "  queuelen: %9d\n"
+		   "  complete: %9s\n"
+		   "  send_only: %8s\n"
+		   "\n",
+		   gid_buf, created, queuelen,
+		   complete ? "yes" : "no",
+		   send_only ? "yes" : "no");
 
 	return 0;
 }
 
-static struct seq_operations ipoib_seq_ops = {
+static struct seq_operations ipoib_mcg_seq_ops = {
 	.start = ipoib_mcg_seq_start,
 	.next  = ipoib_mcg_seq_next,
 	.stop  = ipoib_mcg_seq_stop,
@@ -124,7 +136,7 @@ static int ipoib_mcg_open(struct inode *inode, struct file *file)
 	struct seq_file *seq;
 	int ret;
 
-	ret = seq_open(file, &ipoib_seq_ops);
+	ret = seq_open(file, &ipoib_mcg_seq_ops);
 	if (ret)
 		return ret;
 
@@ -134,7 +146,7 @@ static int ipoib_mcg_open(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static struct file_operations ipoib_fops = {
+static struct file_operations ipoib_mcg_fops = {
 	.owner   = THIS_MODULE,
 	.open    = ipoib_mcg_open,
 	.read    = seq_read,
@@ -142,25 +154,138 @@ static struct file_operations ipoib_fops = {
 	.release = seq_release
 };
 
-int ipoib_create_debug_file(struct net_device *dev)
+static void *ipoib_path_seq_start(struct seq_file *file, loff_t *pos)
+{
+	struct ipoib_path_iter *iter;
+	loff_t n = *pos;
+
+	iter = ipoib_path_iter_init(file->private);
+	if (!iter)
+		return NULL;
+
+	while (n--) {
+		if (ipoib_path_iter_next(iter)) {
+			kfree(iter);
+			return NULL;
+		}
+	}
+
+	return iter;
+}
+
+static void *ipoib_path_seq_next(struct seq_file *file, void *iter_ptr,
+				   loff_t *pos)
+{
+	struct ipoib_path_iter *iter = iter_ptr;
+
+	(*pos)++;
+
+	if (ipoib_path_iter_next(iter)) {
+		kfree(iter);
+		return NULL;
+	}
+
+	return iter;
+}
+
+static void ipoib_path_seq_stop(struct seq_file *file, void *iter_ptr)
+{
+	/* nothing for now */
+}
+
+static int ipoib_path_seq_show(struct seq_file *file, void *iter_ptr)
+{
+	struct ipoib_path_iter *iter = iter_ptr;
+	char gid_buf[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"];
+	struct ipoib_path path;
+	int rate;
+
+	if (!iter)
+		return 0;
+
+	ipoib_path_iter_read(iter, &path);
+
+	format_gid(&path.pathrec.dgid, gid_buf);
+
+	seq_printf(file,
+		   "GID: %s\n"
+		   "  complete: %6s\n",
+		   gid_buf, path.pathrec.dlid ? "yes" : "no");
+
+	if (path.pathrec.dlid) {
+		rate = ib_sa_rate_enum_to_int(path.pathrec.rate) * 25;
+
+		seq_printf(file,
+			   "  DLID:     0x%04x\n"
+			   "  SL: %12d\n"
+			   "  rate: %*d%s Gb/sec\n",
+			   be16_to_cpu(path.pathrec.dlid),
+			   path.pathrec.sl,
+			   10 - ((rate % 10) ? 2 : 0),
+			   rate / 10, rate % 10 ? ".5" : "");
+	}
+
+	seq_putc(file, '\n');
+
+	return 0;
+}
+
+static struct seq_operations ipoib_path_seq_ops = {
+	.start = ipoib_path_seq_start,
+	.next  = ipoib_path_seq_next,
+	.stop  = ipoib_path_seq_stop,
+	.show  = ipoib_path_seq_show,
+};
+
+static int ipoib_path_open(struct inode *inode, struct file *file)
+{
+	struct seq_file *seq;
+	int ret;
+
+	ret = seq_open(file, &ipoib_path_seq_ops);
+	if (ret)
+		return ret;
+
+	seq = file->private_data;
+	seq->private = inode->u.generic_ip;
+
+	return 0;
+}
+
+static struct file_operations ipoib_path_fops = {
+	.owner   = THIS_MODULE,
+	.open    = ipoib_path_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release
+};
+
+void ipoib_create_debug_files(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
-	char name[IFNAMSIZ + sizeof "_mcg"];
+	char name[IFNAMSIZ + sizeof "_path"];
 
 	snprintf(name, sizeof name, "%s_mcg", dev->name);
-
 	priv->mcg_dentry = debugfs_create_file(name, S_IFREG | S_IRUGO,
-					       ipoib_root, dev, &ipoib_fops);
-
-	return priv->mcg_dentry ? 0 : -ENOMEM;
+					       ipoib_root, dev, &ipoib_mcg_fops);
+	if (!priv->mcg_dentry)
+		ipoib_warn(priv, "failed to create mcg debug file\n");
+
+	snprintf(name, sizeof name, "%s_path", dev->name);
+	priv->path_dentry = debugfs_create_file(name, S_IFREG | S_IRUGO,
+						ipoib_root, dev, &ipoib_path_fops);
+	if (!priv->path_dentry)
+		ipoib_warn(priv, "failed to create path debug file\n");
 }
 
-void ipoib_delete_debug_file(struct net_device *dev)
+void ipoib_delete_debug_files(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 
 	if (priv->mcg_dentry)
 		debugfs_remove(priv->mcg_dentry);
+	if (priv->path_dentry)
+		debugfs_remove(priv->path_dentry);
 }
 
 int ipoib_register_debugfs(void)