net: stmmac: create one debugfs dir per net-device

stmmac DebugFS entries are currently global to the driver. As a result,
having more than one stmmac device in the system creates the following
error:
* ERROR stmmaceth, debugfs create directory failed
* stmmac_hw_setup: failed debugFS registration

This also results in being able to access the debugfs information for
the first registered device only.

This patch changes the debugfs structure to have one sub-directory per
net-device. Files under "/sys/kernel/debug/stmmaceth" will now show-up
under /sys/kernel/debug/stmmaceth/ethN/.

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 59 insertions, 23 deletions

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index 2ac9552d1fa3..73bab983edd9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -117,6 +117,12 @@ struct stmmac_priv {
         int use_riwt;
         int irq_wake;
         spinlock_t ptp_lock;
+
+#ifdef CONFIG_DEBUG_FS
+        struct dentry *dbgfs_dir;
+        struct dentry *dbgfs_rings_status;
+        struct dentry *dbgfs_dma_cap;
+#endif
 };
 
 int stmmac_mdio_unregister(struct net_device *ndev);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 05c146f718a3..2c5ce2baca87 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -118,7 +118,7 @@ static irqreturn_t stmmac_interrupt(int irq, void *dev_id);
 
 #ifdef CONFIG_DEBUG_FS
 static int stmmac_init_fs(struct net_device *dev);
-static void stmmac_exit_fs(void);
+static void stmmac_exit_fs(struct net_device *dev);
 #endif
 
 #define STMMAC_COAL_TIMER(x) (jiffies + usecs_to_jiffies(x))
@@ -1916,7 +1916,7 @@ static int stmmac_release(struct net_device *dev)
         netif_carrier_off(dev);
 
 #ifdef CONFIG_DEBUG_FS
-        stmmac_exit_fs();
+        stmmac_exit_fs(dev);
 #endif
 
         stmmac_release_ptp(priv);
@@ -2508,8 +2508,6 @@ static int stmmac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 
 #ifdef CONFIG_DEBUG_FS
 static struct dentry *stmmac_fs_dir;
-static struct dentry *stmmac_rings_status;
-static struct dentry *stmmac_dma_cap;
 
 static void sysfs_display_ring(void *head, int size, int extend_desc,
                                struct seq_file *seq)
@@ -2648,36 +2646,39 @@ static const struct file_operations stmmac_dma_cap_fops = {
 
 static int stmmac_init_fs(struct net_device *dev)
 {
-        /* Create debugfs entries */
-        stmmac_fs_dir = debugfs_create_dir(STMMAC_RESOURCE_NAME, NULL);
+        struct stmmac_priv *priv = netdev_priv(dev);
+
+        /* Create per netdev entries */
+        priv->dbgfs_dir = debugfs_create_dir(dev->name, stmmac_fs_dir);
 
-        if (!stmmac_fs_dir || IS_ERR(stmmac_fs_dir)) {
-                pr_err("ERROR %s, debugfs create directory failed\n",
-                       STMMAC_RESOURCE_NAME);
+        if (!priv->dbgfs_dir || IS_ERR(priv->dbgfs_dir)) {
+                pr_err("ERROR %s/%s, debugfs create directory failed\n",
+                       STMMAC_RESOURCE_NAME, dev->name);
 
                 return -ENOMEM;
         }
 
         /* Entry to report DMA RX/TX rings */
-        stmmac_rings_status = debugfs_create_file("descriptors_status",
-                                                  S_IRUGO, stmmac_fs_dir, dev,
-                                                  &stmmac_rings_status_fops);
+        priv->dbgfs_rings_status =
+                debugfs_create_file("descriptors_status", S_IRUGO,
+                                    priv->dbgfs_dir, dev,
+                                    &stmmac_rings_status_fops);
 
-        if (!stmmac_rings_status || IS_ERR(stmmac_rings_status)) {
+        if (!priv->dbgfs_rings_status || IS_ERR(priv->dbgfs_rings_status)) {
                 pr_info("ERROR creating stmmac ring debugfs file\n");
-                debugfs_remove(stmmac_fs_dir);
+                debugfs_remove_recursive(priv->dbgfs_dir);
 
                 return -ENOMEM;
         }
 
         /* Entry to report the DMA HW features */
-        stmmac_dma_cap = debugfs_create_file("dma_cap", S_IRUGO, stmmac_fs_dir,
-                                             dev, &stmmac_dma_cap_fops);
+        priv->dbgfs_dma_cap = debugfs_create_file("dma_cap", S_IRUGO,
+                                            priv->dbgfs_dir,
+                                            dev, &stmmac_dma_cap_fops);
 
-        if (!stmmac_dma_cap || IS_ERR(stmmac_dma_cap)) {
+        if (!priv->dbgfs_dma_cap || IS_ERR(priv->dbgfs_dma_cap)) {
                 pr_info("ERROR creating stmmac MMC debugfs file\n");
-                debugfs_remove(stmmac_rings_status);
-                debugfs_remove(stmmac_fs_dir);
+                debugfs_remove_recursive(priv->dbgfs_dir);
 
                 return -ENOMEM;
         }
@@ -2685,11 +2686,11 @@ static int stmmac_init_fs(struct net_device *dev)
         return 0;
 }
 
-static void stmmac_exit_fs(void)
+static void stmmac_exit_fs(struct net_device *dev)
 {
-        debugfs_remove(stmmac_rings_status);
-        debugfs_remove(stmmac_dma_cap);
-        debugfs_remove(stmmac_fs_dir);
+        struct stmmac_priv *priv = netdev_priv(dev);
+
+        debugfs_remove_recursive(priv->dbgfs_dir);
 }
 #endif /* CONFIG_DEBUG_FS */
 
@@ -3149,6 +3150,35 @@ err:
 __setup("stmmaceth=", stmmac_cmdline_opt);
 #endif /* MODULE */
 
+static int __init stmmac_init(void)
+{
+#ifdef CONFIG_DEBUG_FS
+        /* Create debugfs main directory if it doesn't exist yet */
+        if (!stmmac_fs_dir) {
+                stmmac_fs_dir = debugfs_create_dir(STMMAC_RESOURCE_NAME, NULL);
+
+                if (!stmmac_fs_dir || IS_ERR(stmmac_fs_dir)) {
+                        pr_err("ERROR %s, debugfs create directory failed\n",
+                               STMMAC_RESOURCE_NAME);
+
+                        return -ENOMEM;
+                }
+        }
+#endif
+
+        return 0;
+}
+
+static void __exit stmmac_exit(void)
+{
+#ifdef CONFIG_DEBUG_FS
+        debugfs_remove_recursive(stmmac_fs_dir);
+#endif
+}
+
+module_init(stmmac_init)
+module_exit(stmmac_exit)
+
 MODULE_DESCRIPTION("STMMAC 10/100/1000 Ethernet device driver");
 MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
 MODULE_LICENSE("GPL");