net: hns3: refactor dump bd info of debugfs

Currently, the debugfs command for bd info is implemented
by "echo xxxx > cmd", and record the information in dmesg.
It's unnecessary and heavy.

To improve it, add two debugfs directories "tx_bd_info" and
"rx_bd_info", and create a file for each queue under these
two directories, and query the bd info of specific queue by
"cat tx_bd_info/tx_bd_queue*" or "cat rx_bd_info/rx_bd_queue*",
return the result to userspace, rather than record in dmesg.

The display style is below:
$ cat rx_bd_info/rx_bd_queue0
Queue 0 rx bd info:
BD_IDX   L234_INFO  PKT_LEN   SIZE...
0        0x0             60     60...
1        0x0           1512   1512...

$ cat tx_bd_info/tx_bd_queue0
Queue 0 tx bd info:
BD_IDX     ADDRESS  VLAN_TAG  SIZE...
0          0x0          0        0...
1          0x0          0        0...
Signed-off-by: Huazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/hisilicon/hns3/hnae3.h

@@ -255,6 +255,8 @@ enum hnae3_dbg_cmd {
 	HNAE3_DBG_CMD_TM_PRI,
 	HNAE3_DBG_CMD_TM_QSET,
 	HNAE3_DBG_CMD_DEV_INFO,
+	HNAE3_DBG_CMD_TX_BD,
+	HNAE3_DBG_CMD_RX_BD,
 	HNAE3_DBG_CMD_UNKNOWN,
 };
 

drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.h

@@ -5,10 +5,28 @@
 #define __HNS3_DEBUGFS_H
 
 #define HNS3_DBG_READ_LEN	65536
+#define HNS3_DBG_READ_LEN_4MB	0x400000
 #define HNS3_DBG_WRITE_LEN	1024
 
+#define HNS3_DBG_DATA_STR_LEN	32
+#define HNS3_DBG_INFO_LEN	256
+#define HNS3_DBG_ITEM_NAME_LEN	32
+#define HNS3_DBG_FILE_NAME_LEN	16
+
+struct hns3_dbg_item {
+	char name[HNS3_DBG_ITEM_NAME_LEN];
+	u16 interval; /* blank numbers after the item */
+};
+
+struct hns3_dbg_data {
+	struct hnae3_handle *handle;
+	u16 qid;
+};
+
 enum hns3_dbg_dentry_type {
 	HNS3_DBG_DENTRY_TM,
+	HNS3_DBG_DENTRY_TX_BD,
+	HNS3_DBG_DENTRY_RX_BD,
 	HNS3_DBG_DENTRY_COMMON,
 };
 
@@ -29,6 +47,7 @@ struct hns3_dbg_cmd_info {
 struct hns3_dbg_func {
 	enum hnae3_dbg_cmd cmd;
 	int (*dbg_dump)(struct hnae3_handle *handle, char *buf, int len);
+	int (*dbg_dump_bd)(struct hns3_dbg_data *data, char *buf, int len);
 };
 
 struct hns3_dbg_cap_info {

drivers/net/ethernet/hisilicon/hns3/hns3_enet.c

@@ -634,7 +634,7 @@ static int hns3_nic_set_real_num_queue(struct net_device *netdev)
 	return 0;
 }
 
-static u16 hns3_get_max_available_channels(struct hnae3_handle *h)
+u16 hns3_get_max_available_channels(struct hnae3_handle *h)
 {
 	u16 alloc_tqps, max_rss_size, rss_size;
 

drivers/net/ethernet/hisilicon/hns3/hns3_enet.h

@@ -655,4 +655,5 @@ void hns3_dbg_uninit(struct hnae3_handle *handle);
 void hns3_dbg_register_debugfs(const char *debugfs_dir_name);
 void hns3_dbg_unregister_debugfs(void);
 void hns3_shinfo_pack(struct skb_shared_info *shinfo, __u32 *size);
+u16 hns3_get_max_available_channels(struct hnae3_handle *h);
 #endif