[Ocfs2-tools-devel] [PATCH] debugfs.ocfs2: Allow dumping fs locks from a file

[Mark Fasheh]

This way we can review locking state even if all a customer provides us is
the contents of /sys/kernel/debug/ocfs2/locking_state.

Signed-off-by: Mark Fasheh <mfasheh at suse.com>
---
 debugfs.ocfs2/commands.c              |   22 +++++++++++++-----
 debugfs.ocfs2/dump_fs_locks.c         |   39 ++++++++++++++++++++------------
 debugfs.ocfs2/include/dump_fs_locks.h |    4 +-
 3 files changed, 42 insertions(+), 23 deletions(-)

diff --git a/debugfs.ocfs2/commands.c b/debugfs.ocfs2/commands.c
index b6aa39a..0e46151 100644
--- a/debugfs.ocfs2/commands.c
+++ b/debugfs.ocfs2/commands.c
@@ -836,7 +836,7 @@ static void do_help (char **args)
 	printf ("encode <filespec>\t\t\tShow lock name\n");
 	printf ("extent <block#>\t\t\t\tShow extent block\n");
 	printf ("findpath <block#>\t\t\tList one pathname of the inode/lockname\n");
-	printf ("fs_locks [-l] [-B]\t\t\tShow live fs locking state\n");
+	printf ("fs_locks [-f <file>] [-l] [-B]\t\t\tShow live fs locking state\n");
 	printf ("group <block#>\t\t\t\tShow chain group\n");
 	printf ("hb\t\t\t\t\tShows the used heartbeat blocks\n");
 	printf ("help, ?\t\t\t\t\tThis information\n");
@@ -1521,14 +1521,12 @@ static void do_fs_locks(char **args)
 	int only_busy = 0;
 	int c, argc;
 	struct list_head locklist;
-
-	if (check_device_open())
-		return;
+	char *path = NULL, *uuid_str = NULL;
 
 	for (argc = 0; (args[argc]); ++argc);
 	optind = 0;
 
-	while ((c = getopt(argc, args, "lB")) != -1) {
+	while ((c = getopt(argc, args, "lBf:")) != -1) {
 		switch (c) {
 		case 'l':
 			dump_lvbs = 1;
@@ -1536,10 +1534,21 @@ static void do_fs_locks(char **args)
 		case 'B':
 			only_busy = 1;
 			break;
+		case 'f':
+			path = optarg;
+			break;
 		default:
 			break;
 		}
 	}
+	if ((path == NULL)) {
+		/* Only error for a missing device if we're asked to
+		 * read from a live file system. */
+		if (check_device_open())
+			return;
+
+		uuid_str = gbls.fs->uuid_str;
+	}
 
 	init_stringlist(&locklist);
 
@@ -1550,7 +1559,8 @@ static void do_fs_locks(char **args)
 	}
 
 	out = open_pager(gbls.interactive);
-	dump_fs_locks(gbls.fs->uuid_str, out, dump_lvbs, only_busy, &locklist);
+	dump_fs_locks(uuid_str, out, path, dump_lvbs, only_busy,
+		      &locklist);
 	close_pager(out);
 
 	free_stringlist(&locklist);
diff --git a/debugfs.ocfs2/dump_fs_locks.c b/debugfs.ocfs2/dump_fs_locks.c
index 2d5d718..1d4a56e 100644
--- a/debugfs.ocfs2/dump_fs_locks.c
+++ b/debugfs.ocfs2/dump_fs_locks.c
@@ -416,28 +416,37 @@ static int dump_one_lockres(FILE *file, FILE *out, int lvbs, int only_busy,
 	return ret;
 }
 
-void dump_fs_locks(char *uuid_str, FILE *out, int dump_lvbs, int only_busy,
-		   struct list_head *locklist)
+void dump_fs_locks(char *uuid_str, FILE *out, char *path, int dump_lvbs,
+		   int only_busy, struct list_head *locklist)
 {
 	errcode_t ret;
 	char debugfs_path[PATH_MAX];
 	FILE *file;
 	int show_select;
 
-	ret = get_debugfs_path(debugfs_path, sizeof(debugfs_path));
-	if (ret) {
-		fprintf(stderr, "Could not locate debugfs file system. "
-			"Perhaps it is not mounted?\n");
-		return;
-	}
+	if (path == NULL) {
+		ret = get_debugfs_path(debugfs_path, sizeof(debugfs_path));
+		if (ret) {
+			fprintf(stderr, "Could not locate debugfs file system. "
+				"Perhaps it is not mounted?\n");
+			return;
+		}
 
-	ret = open_debugfs_file(debugfs_path, "ocfs2", uuid_str,
-				"locking_state", &file);
-	if (ret) {
-		fprintf(stderr, "Could not open debug state for \"%s\".\n"
-			"Perhaps that OCFS2 file system is not mounted?\n",
-			uuid_str);
-		return;
+		ret = open_debugfs_file(debugfs_path, "ocfs2", uuid_str,
+					"locking_state", &file);
+		if (ret) {
+			fprintf(stderr, "Could not open debug state for "
+				"\"%s\".\nPerhaps that OCFS2 file system is "
+				"not mounted?\n", uuid_str);
+			return;
+		}
+	} else {
+		file = fopen(path, "r");
+		if (!file) {
+			fprintf(stderr, "Could not open file at \"%s\"\n",
+				path);
+			return;
+		}
 	}
 
 	show_select = !list_empty(locklist);
diff --git a/debugfs.ocfs2/include/dump_fs_locks.h b/debugfs.ocfs2/include/dump_fs_locks.h
index f6da59e..9445c31 100644
--- a/debugfs.ocfs2/include/dump_fs_locks.h
+++ b/debugfs.ocfs2/include/dump_fs_locks.h
@@ -25,7 +25,7 @@
 #ifndef _DUMP_FS_LOCKS_H_
 #define _DUMP_FS_LOCKS_H_
 
-void dump_fs_locks(char *uuid, FILE *out, int dump_lvbs, int only_busy,
-		   struct list_head *locklist);
+void dump_fs_locks(char *uuid_str, FILE *out, char *path, int dump_lvbs,
+		   int only_busy, struct list_head *locklist);
 
 #endif		/* _DUMP_FS_LOCKS_H_ */
-- 
1.5.4.1