[RFC v5 5/5] drm/xe/RAS: send multicast event on occurrence of an error

[Aravind Iddamsetty]

Whenever a correctable or an uncorrectable error happens an event is sent
to the corresponding listeners of these groups.

v2: Rebase
v3: protect with CONFIG_NET define.

Reviewed-by: Michael J. Ruhl <michael.j.ruhl at intel.com> #v2
Signed-off-by: Aravind Iddamsetty <aravind.iddamsetty at linux.intel.com>
---
 drivers/gpu/drm/xe/xe_hw_error.c | 41 ++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_hw_error.c b/drivers/gpu/drm/xe/xe_hw_error.c
index bdd9c88674b2..e6e2e6250b70 100644
--- a/drivers/gpu/drm/xe/xe_hw_error.c
+++ b/drivers/gpu/drm/xe/xe_hw_error.c
@@ -2,6 +2,8 @@
 /*
  * Copyright © 2023 Intel Corporation
  */
+#include <net/genetlink.h>
+#include <uapi/drm/drm_netlink.h>
 
 #include "xe_gt_printk.h"
 #include "xe_hw_error.h"
@@ -776,6 +778,43 @@ xe_soc_hw_error_handler(struct xe_tile *tile, const enum hardware_error hw_err)
 				(HARDWARE_ERROR_MAX << 1) + 1);
 }
 
+#ifdef CONFIG_NET
+static void
+generate_netlink_event(struct xe_device *xe, const enum hardware_error hw_err)
+{
+	struct sk_buff *msg;
+	void *hdr;
+
+	if (!xe->drm.drm_genl_family)
+		return;
+
+	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+	if (!msg) {
+		drm_dbg_driver(&xe->drm, "couldn't allocate memory for error multicast event\n");
+		return;
+	}
+
+	hdr = genlmsg_put(msg, 0, 0, xe->drm.drm_genl_family, 0, DRM_RAS_CMD_ERROR_EVENT);
+	if (!hdr) {
+		drm_dbg_driver(&xe->drm, "mutlicast msg buffer is small\n");
+		nlmsg_free(msg);
+		return;
+	}
+
+	genlmsg_end(msg, hdr);
+
+	genlmsg_multicast(xe->drm.drm_genl_family, msg, 0,
+			  hw_err ?
+			  DRM_GENL_MCAST_UNCORR_ERR
+			  : DRM_GENL_MCAST_CORR_ERR,
+			  GFP_ATOMIC);
+}
+#else
+static void
+generate_netlink_event(struct xe_device *xe, const enum hardware_error hw_err)
+{}
+#endif
+
 static void
 xe_hw_error_source_handler(struct xe_tile *tile, const enum hardware_error hw_err)
 {
@@ -837,6 +876,8 @@ xe_hw_error_source_handler(struct xe_tile *tile, const enum hardware_error hw_er
 	}
 
 	xe_mmio_write32(&tile->mmio, DEV_ERR_STAT_REG(hw_err), errsrc);
+
+	generate_netlink_event(tile_to_xe(tile), hw_err);
 unlock:
 	spin_unlock_irqrestore(&tile_to_xe(tile)->irq.lock, flags);
 }
-- 
2.25.1