From c26fb3bef2e2bd770d5cea3f1b32b895baf3048b Mon Sep 17 00:00:00 2001
From: Thomas Schoebel-Theuer <mars@box>
Date: Wed, 21 Oct 2020 22:29:34 +0200
Subject: [PATCH] infra: invalidate user caches

---
 kernel/mars_server.c      |  2 ++
 kernel/sy_old/mars_main.c | 20 +++++++++++++++++++-
 kernel/sy_old/strategy.h  |  3 +++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/kernel/mars_server.c b/kernel/mars_server.c
index 49bccc61..bd67ce5b 100644
--- a/kernel/mars_server.c
+++ b/kernel/mars_server.c
@@ -607,6 +607,7 @@ int handler_thread(void *data)
 				status = -EPERM;
 				break;
 			}
+			invalidate_user_cache();
 
 			status =
 				ordered_symlink(cmd.cmd_str1,
@@ -629,6 +630,7 @@ int handler_thread(void *data)
 
 			status = mars_stat(cmd.cmd_str2, &probe, true);
 			if (status < 0) {
+				invalidate_user_cache();
 				activate_peer(cmd.cmd_str1, NULL, NULL, true);
 			}
 			status = 0;
diff --git a/kernel/sy_old/mars_main.c b/kernel/sy_old/mars_main.c
index 8e5dccab..ce1631d6 100644
--- a/kernel/sy_old/mars_main.c
+++ b/kernel/sy_old/mars_main.c
@@ -223,6 +223,15 @@ void _crashme(int mode, bool do_sync)
 
 #endif
 
+void invalidate_user_cache(void)
+{
+	const char *path;
+
+	path = path_make("/mars/cache-%s/invalid", my_id());
+	ordered_symlink("1", path, NULL);
+	brick_string_free(path);
+}
+
 #define GLOBAL_PATH_LIST			\
   "/mars"					\
   "|/mars/ips/"					\
@@ -2629,6 +2638,14 @@ int run_bone(struct mars_peerinfo *peer, struct mars_dent *remote_dent)
 #endif
 		}
 	} else if (S_ISLNK(remote_dent->new_stat.mode) && remote_dent->new_link) {
+		/* is something in /mars/ips/ (or a guest membership) updated ? */
+		if ((!stat_ok ||
+		     lamport_time_compare(&remote_dent->new_stat.mtime,
+					  &local_stat.mtime) > 0) &&
+		    (!strncmp(remote_dent->d_name, "device-", 7) ||
+		     !strncmp(remote_path, MARS_IP_STR, strlen(MARS_IP_STR))))
+			invalidate_user_cache();
+
 		/* Important: not not create .deleted values
 		 * unless the object already exists.
 		 */
@@ -2638,7 +2655,8 @@ int run_bone(struct mars_peerinfo *peer, struct mars_dent *remote_dent)
 			status = ordered_symlink(remote_dent->new_link,
 						 remote_path,
 						 &remote_dent->new_stat.mtime);
-			MARS_DBG("create symlink '%s' -> '%s' status = %d\n", remote_path, remote_dent->new_link, status);
+			MARS_DBG("create symlink '%s' -> '%s' status = %d\n",
+				 remote_path, remote_dent->new_link, status);
 			run_trigger = true;
 			if (!status &&
 			    (!strncmp(remote_dent->d_name, "primary", 7) ||
diff --git a/kernel/sy_old/strategy.h b/kernel/sy_old/strategy.h
index 486375cd..ea809df0 100644
--- a/kernel/sy_old/strategy.h
+++ b/kernel/sy_old/strategy.h
@@ -72,6 +72,9 @@ extern int mars_keep_msg;
 
 extern int mars_fast_fullsync;
 
+#define MARS_IP_STR      "/mars/ips/ip-"
+extern void invalidate_user_cache(void);
+
 extern char *my_id(void);
 extern const char *my_uuid;