bnxt_en: implement devlink dev reload driver_reinit

The RTNL lock must be held between down and up to prevent interleaving
state changes, especially since external state changes might release
and allocate different driver resource subsets that would otherwise
need to be tracked and carefully handled. If the down function fails,
then devlink will not call the corresponding up function, thus the
lock is released in the down error paths.

v2: Don't use devlink_reload_disable() and devlink_reload_enable().
Instead, check that the netdev is not in unregistered state before
proceeding with reload.
Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-Off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -49,8 +49,6 @@
 #include <linux/log2.h>
 #include <linux/aer.h>
 #include <linux/bitmap.h>
-#include <linux/ptp_clock_kernel.h>
-#include <linux/timecounter.h>
 #include <linux/cpu_rmap.h>
 #include <linux/cpumask.h>
 #include <net/pkt_cls.h>
@@ -4603,7 +4601,7 @@ int bnxt_hwrm_func_drv_rgtr(struct bnxt *bp, unsigned long *bmap, int bmap_size,
 	return rc;
 }
 
-static int bnxt_hwrm_func_drv_unrgtr(struct bnxt *bp)
+int bnxt_hwrm_func_drv_unrgtr(struct bnxt *bp)
 {
 	struct hwrm_func_drv_unrgtr_input *req;
 	int rc;
@@ -7144,7 +7142,7 @@ static void bnxt_free_ctx_pg_tbls(struct bnxt *bp,
 	ctx_pg->nr_pages = 0;
 }
 
-static void bnxt_free_ctx_mem(struct bnxt *bp)
+void bnxt_free_ctx_mem(struct bnxt *bp)
 {
 	struct bnxt_ctx_mem_info *ctx = bp->ctx;
 	int i;
@@ -9198,7 +9196,7 @@ static char *bnxt_report_fec(struct bnxt_link_info *link_info)
 	}
 }
 
-static void bnxt_report_link(struct bnxt *bp)
+void bnxt_report_link(struct bnxt *bp)
 {
 	if (bp->link_info.link_up) {
 		const char *signal = "";
@@ -9643,8 +9641,6 @@ static int bnxt_hwrm_shutdown_link(struct bnxt *bp)
 	return hwrm_req_send(bp, req);
 }
 
-static int bnxt_fw_init_one(struct bnxt *bp);
-
 static int bnxt_fw_reset_via_optee(struct bnxt *bp)
 {
 #ifdef CONFIG_TEE_BNXT_FW
@@ -10279,7 +10275,7 @@ void bnxt_half_close_nic(struct bnxt *bp)
 	bnxt_free_mem(bp, false);
 }
 
-static void bnxt_reenable_sriov(struct bnxt *bp)
+void bnxt_reenable_sriov(struct bnxt *bp)
 {
 	if (BNXT_PF(bp)) {
 		struct bnxt_pf_info *pf = &bp->pf;
@@ -11950,7 +11946,7 @@ static void bnxt_fw_init_one_p3(struct bnxt *bp)
 
 static int bnxt_probe_phy(struct bnxt *bp, bool fw_dflt);
 
-static int bnxt_fw_init_one(struct bnxt *bp)
+int bnxt_fw_init_one(struct bnxt *bp)
 {
 	int rc;
 

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -2230,11 +2230,13 @@ void bnxt_set_ring_params(struct bnxt *);
 int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode);
 int bnxt_hwrm_func_drv_rgtr(struct bnxt *bp, unsigned long *bmap,
 			    int bmap_size, bool async_only);
+int bnxt_hwrm_func_drv_unrgtr(struct bnxt *bp);
 int bnxt_get_nr_rss_ctxs(struct bnxt *bp, int rx_rings);
 int bnxt_hwrm_vnic_cfg(struct bnxt *bp, u16 vnic_id);
 int __bnxt_hwrm_get_tx_rings(struct bnxt *bp, u16 fid, int *tx_rings);
 int bnxt_nq_rings_in_use(struct bnxt *bp);
 int bnxt_hwrm_set_coal(struct bnxt *);
+void bnxt_free_ctx_mem(struct bnxt *bp);
 unsigned int bnxt_get_max_func_stat_ctxs(struct bnxt *bp);
 unsigned int bnxt_get_avail_stat_ctxs_for_en(struct bnxt *bp);
 unsigned int bnxt_get_max_func_cp_rings(struct bnxt *bp);
@@ -2243,6 +2245,7 @@ int bnxt_get_avail_msix(struct bnxt *bp, int num);
 int bnxt_reserve_rings(struct bnxt *bp, bool irq_re_init);
 void bnxt_tx_disable(struct bnxt *bp);
 void bnxt_tx_enable(struct bnxt *bp);
+void bnxt_report_link(struct bnxt *bp);
 int bnxt_update_link(struct bnxt *bp, bool chng_link_state);
 int bnxt_hwrm_set_pause(struct bnxt *);
 int bnxt_hwrm_set_link_setting(struct bnxt *, bool, bool);
@@ -2255,6 +2258,7 @@ int bnxt_hwrm_fw_set_time(struct bnxt *);
 int bnxt_open_nic(struct bnxt *, bool, bool);
 int bnxt_half_open_nic(struct bnxt *bp);
 void bnxt_half_close_nic(struct bnxt *bp);
+void bnxt_reenable_sriov(struct bnxt *bp);
 int bnxt_close_nic(struct bnxt *, bool, bool);
 int bnxt_dbg_hwrm_rd_reg(struct bnxt *bp, u32 reg_off, u16 num_words,
 			 u32 *reg_buf);
@@ -2262,6 +2266,7 @@ void bnxt_fw_exception(struct bnxt *bp);
 void bnxt_fw_reset(struct bnxt *bp);
 int bnxt_check_rings(struct bnxt *bp, int tx, int rx, bool sh, int tcs,
 		     int tx_xdp);
+int bnxt_fw_init_one(struct bnxt *bp);
 int bnxt_setup_mq_tc(struct net_device *dev, u8 tc);
 int bnxt_get_max_rings(struct bnxt *, int *, int *, bool);
 int bnxt_restore_pf_fw_resources(struct bnxt *bp);

drivers/net/ethernet/broadcom/bnxt/bnxt_devlink.c

@@ -16,6 +16,8 @@
 #include "bnxt_vfr.h"
 #include "bnxt_devlink.h"
 #include "bnxt_ethtool.h"
+#include "bnxt_ulp.h"
+#include "bnxt_ptp.h"
 
 static int
 bnxt_dl_flash_update(struct devlink *dl,
@@ -280,6 +282,98 @@ void bnxt_dl_health_recovery_done(struct bnxt *bp)
 static int bnxt_dl_info_get(struct devlink *dl, struct devlink_info_req *req,
 			    struct netlink_ext_ack *extack);
 
+static int bnxt_dl_reload_down(struct devlink *dl, bool netns_change,
+			       enum devlink_reload_action action,
+			       enum devlink_reload_limit limit,
+			       struct netlink_ext_ack *extack)
+{
+	struct bnxt *bp = bnxt_get_bp_from_dl(dl);
+	int rc = 0;
+
+	switch (action) {
+	case DEVLINK_RELOAD_ACTION_DRIVER_REINIT: {
+		if (BNXT_PF(bp) && bp->pf.active_vfs) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "reload is unsupported when VFs are allocated\n");
+			return -EOPNOTSUPP;
+		}
+		rtnl_lock();
+		if (bp->dev->reg_state == NETREG_UNREGISTERED) {
+			rtnl_unlock();
+			return -ENODEV;
+		}
+		bnxt_ulp_stop(bp);
+		if (netif_running(bp->dev)) {
+			rc = bnxt_close_nic(bp, true, true);
+			if (rc) {
+				NL_SET_ERR_MSG_MOD(extack, "Failed to close");
+				dev_close(bp->dev);
+				rtnl_unlock();
+				break;
+			}
+		}
+		bnxt_vf_reps_free(bp);
+		rc = bnxt_hwrm_func_drv_unrgtr(bp);
+		if (rc) {
+			NL_SET_ERR_MSG_MOD(extack, "Failed to deregister");
+			if (netif_running(bp->dev))
+				dev_close(bp->dev);
+			rtnl_unlock();
+			break;
+		}
+		bnxt_cancel_reservations(bp, false);
+		bnxt_free_ctx_mem(bp);
+		kfree(bp->ctx);
+		bp->ctx = NULL;
+		break;
+	}
+	default:
+		rc = -EOPNOTSUPP;
+	}
+
+	return rc;
+}
+
+static int bnxt_dl_reload_up(struct devlink *dl, enum devlink_reload_action action,
+			     enum devlink_reload_limit limit, u32 *actions_performed,
+			     struct netlink_ext_ack *extack)
+{
+	struct bnxt *bp = bnxt_get_bp_from_dl(dl);
+	int rc = 0;
+
+	*actions_performed = 0;
+	switch (action) {
+	case DEVLINK_RELOAD_ACTION_DRIVER_REINIT: {
+		bnxt_fw_init_one(bp);
+		bnxt_vf_reps_alloc(bp);
+		if (netif_running(bp->dev))
+			rc = bnxt_open_nic(bp, true, true);
+		bnxt_ulp_start(bp, rc);
+		if (!rc) {
+			bnxt_reenable_sriov(bp);
+			bnxt_ptp_reapply_pps(bp);
+		}
+		break;
+	}
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	if (!rc) {
+		bnxt_print_device_info(bp);
+		if (netif_running(bp->dev)) {
+			mutex_lock(&bp->link_lock);
+			bnxt_report_link(bp);
+			mutex_unlock(&bp->link_lock);
+		}
+		*actions_performed |= BIT(action);
+	} else if (netif_running(bp->dev)) {
+		dev_close(bp->dev);
+	}
+	rtnl_unlock();
+	return rc;
+}
+
 static const struct devlink_ops bnxt_dl_ops = {
 #ifdef CONFIG_BNXT_SRIOV
 	.eswitch_mode_set = bnxt_dl_eswitch_mode_set,
@@ -287,6 +381,9 @@ static const struct devlink_ops bnxt_dl_ops = {
 #endif /* CONFIG_BNXT_SRIOV */
 	.info_get	  = bnxt_dl_info_get,
 	.flash_update	  = bnxt_dl_flash_update,
+	.reload_actions	  = BIT(DEVLINK_RELOAD_ACTION_DRIVER_REINIT),
+	.reload_down	  = bnxt_dl_reload_down,
+	.reload_up	  = bnxt_dl_reload_up,
 };
 
 static const struct devlink_ops bnxt_vf_dl_ops;

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c

@@ -11,9 +11,7 @@
 #include <linux/pci.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
-#include <linux/ptp_clock_kernel.h>
 #include <linux/net_tstamp.h>
-#include <linux/timecounter.h>
 #include <linux/timekeeping.h>
 #include <linux/ptp_classify.h>
 #include "bnxt_hsi.h"

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h

@@ -10,6 +10,9 @@
 #ifndef BNXT_PTP_H
 #define BNXT_PTP_H
 
+#include <linux/ptp_clock_kernel.h>
+#include <linux/timecounter.h>
+
 #define BNXT_PTP_GRC_WIN	6
 #define BNXT_PTP_GRC_WIN_BASE	0x6000