[PATCH v2 2/5] pstore/platform: pass max_reason to kmesg dump

[Pavel Tatashin]

Add a new field to pstore_info that passes information about kmesg dump
maximum reason.

This allows a finer control of what kmesg dumps are stored on pstore
device.

Those clients that do not explicitly set this field (keep it equal to 0),
get the default behavior: dump only Oops and Panics, and dump everything
if printk.always_kmsg_dump is provided.

Signed-off-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
---
 fs/pstore/platform.c   | 4 +++-
 include/linux/pstore.h | 3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c
index 408277ee3cdb..75bf8a43f92a 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -602,8 +602,10 @@ int pstore_register(struct pstore_info *psi)
 	if (pstore_is_mounted())
 		pstore_get_records(0);
 
-	if (psi->flags & PSTORE_FLAGS_DMESG)
+	if (psi->flags & PSTORE_FLAGS_DMESG) {
+		pstore_dumper.max_reason = psinfo->max_reason;
 		pstore_register_kmsg();
+	}
 	if (psi->flags & PSTORE_FLAGS_CONSOLE)
 		pstore_register_console();
 	if (psi->flags & PSTORE_FLAGS_FTRACE)
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index e779441e6d26..45ae424bfeb5 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -97,6 +97,8 @@ struct pstore_record {
  * @read_mutex:	serializes @open, @read, @close, and @erase callbacks
  * @flags:	bitfield of frontends the backend can accept writes for
  * @data:	backend-private pointer passed back during callbacks
+ * @max_reason: Used when PSTORE_FLAGS_DMESG is set. Contains the
+ *              kmsg_dump_reason enum value.
  *
  * Callbacks:
  *
@@ -180,6 +182,7 @@ struct pstore_info {
 
 	int		flags;
 	void		*data;
+	int		max_reason;
 
 	int		(*open)(struct pstore_info *psi);
 	int		(*close)(struct pstore_info *psi);
-- 
2.25.1