[PATCH 4/7] cxl/pci: Hold memdev lock in cxl_event_trace_record()

[Li Ming]

This is a preparatory patch for the following changes.

To enable endpoint validity checks in cxl_dpa_to_region().
cxl_dpa_to_region() has to require caller to hold CXL memdev lock to
ensure the CXL memdev probing is completed.

So holding the given CXL memdev lock before invoking cxl_dpa_to_region()
in cxl_event_trace_record().

Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Li Ming <ming.li@xxxxxxxxxxxx>
---
 drivers/cxl/core/mbox.c | 5 +++--
 drivers/cxl/cxlmem.h    | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index e7a6452bf544..3f34bbabf4d3 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -893,7 +893,7 @@ int cxl_enumerate_cmds(struct cxl_memdev_state *mds)
 }
 EXPORT_SYMBOL_NS_GPL(cxl_enumerate_cmds, "CXL");
 
-void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
+void cxl_event_trace_record(struct cxl_memdev *cxlmd,
 			    enum cxl_event_log_type type,
 			    enum cxl_event_type event_type,
 			    const uuid_t *uuid, union cxl_event *evt)
@@ -920,6 +920,7 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
 		 * translations. Take topology mutation locks and lookup
 		 * { HPA, REGION } from { DPA, MEMDEV } in the event record.
 		 */
+		guard(device)(&cxlmd->dev);
 		guard(rwsem_read)(&cxl_rwsem.region);
 		guard(rwsem_read)(&cxl_rwsem.dpa);
 
@@ -968,7 +969,7 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
 }
 EXPORT_SYMBOL_NS_GPL(cxl_event_trace_record, "CXL");
 
-static void __cxl_event_trace_record(const struct cxl_memdev *cxlmd,
+static void __cxl_event_trace_record(struct cxl_memdev *cxlmd,
 				     enum cxl_event_log_type type,
 				     struct cxl_event_record_raw *record)
 {
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index e21d744d639b..7a34a19c02c8 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -864,7 +864,7 @@ void set_exclusive_cxl_commands(struct cxl_memdev_state *mds,
 void clear_exclusive_cxl_commands(struct cxl_memdev_state *mds,
 				  unsigned long *cmds);
 void cxl_mem_get_event_records(struct cxl_memdev_state *mds, u32 status);
-void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
+void cxl_event_trace_record(struct cxl_memdev *cxlmd,
 			    enum cxl_event_log_type type,
 			    enum cxl_event_type event_type,
 			    const uuid_t *uuid, union cxl_event *evt);

-- 
2.43.0