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

[Tao Ma <tao.ma@oracle.com>]

Signed-off-by: Tao Ma <tao.ma@oracle.com>

Mark Fasheh wrote:
> This way we can review locking state even if all a customer provides us is
> the contents of /sys/kernel/debug/o2dlm/locking_state.
> 
> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
> ---
>  debugfs.ocfs2/commands.c               |   36 ++++++++++++++++++++++-------
>  debugfs.ocfs2/dump_dlm_locks.c         |   38 ++++++++++++++++++++-----------
>  debugfs.ocfs2/include/dump_dlm_locks.h |    2 +-
>  3 files changed, 52 insertions(+), 24 deletions(-)
> 
> diff --git a/debugfs.ocfs2/commands.c b/debugfs.ocfs2/commands.c
> index 0e46151..06b6c98 100644
> --- a/debugfs.ocfs2/commands.c
> +++ b/debugfs.ocfs2/commands.c
> @@ -831,7 +831,7 @@ static void do_help (char **args)
>  	printf ("controld dump\t\t\tObtain information from ocfs2_controld\n");
>  	printf ("curdev\t\t\t\t\tShow current device\n");
>  	printf ("decode <lockname#> ...\t\t\tDecode block#(s) from the lockname(s)\n");
> -	printf ("dlm_locks [-l] lockname\t\t\tShow live dlm locking state\n");
> +	printf ("dlm_locks [-f <file>] [-l] lockname\t\t\tShow live dlm locking state\n");
>  	printf ("dump [-p] <filespec> <outfile>\t\tDumps file to outfile on a mounted fs\n");
>  	printf ("encode <filespec>\t\t\tShow lock name\n");
>  	printf ("extent <block#>\t\t\t\tShow extent block\n");
> @@ -1485,26 +1485,44 @@ static void do_dlm_locks(char **args)
>  	int dump_lvbs = 0;
>  	int i;
>  	struct list_head locklist;
> -
> -	if (check_device_open())
> -		return;
> +	char *path = NULL, *uuid_str = NULL;
> +	int c, argc;
>  
>  	init_stringlist(&locklist);
>  
> -	i = 1;
> -	if (args[i] && strlen(args[i])) {
> -		if (!strcmp("-l", args[i])) {
> +	for (argc = 0; (args[argc]); ++argc);
> +	optind = 0;
> +
> +	while ((c = getopt(argc, args, "lf:")) != -1) {
> +		switch (c) {
> +		case 'l':
>  			dump_lvbs = 1;
> -			i++;
> +			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;
> +	}
>  
> +	i = optind;
> +	if (args[i] && strlen(args[i])) {
>  		for ( ; args[i] && strlen(args[i]); ++i)
>  			if (add_to_stringlist(args[i], &locklist))
>  				break;
>  	}
>  
>  	out = open_pager(gbls.interactive);
> -	dump_dlm_locks(gbls.fs->uuid_str, out, dump_lvbs, &locklist);
> +	dump_dlm_locks(uuid_str, out, path, dump_lvbs, &locklist);
>  	close_pager(out);
>  
>  	free_stringlist(&locklist);
> diff --git a/debugfs.ocfs2/dump_dlm_locks.c b/debugfs.ocfs2/dump_dlm_locks.c
> index b946821..6344ff1 100644
> --- a/debugfs.ocfs2/dump_dlm_locks.c
> +++ b/debugfs.ocfs2/dump_dlm_locks.c
> @@ -411,7 +411,7 @@ static int get_next_dlm_lockname(FILE *file, char *name, int len)
>  	return 0;
>  }
>  
> -void dump_dlm_locks(char *uuid, FILE *out, int dump_lvbs,
> +void dump_dlm_locks(char *uuid, FILE *out, char *path, int dump_lvbs,
>  		    struct list_head *locklist)
>  {
>  	errcode_t ret;
> @@ -421,20 +421,30 @@ void dump_dlm_locks(char *uuid, FILE *out, int dump_lvbs,
>  	struct lockres res;
>  	int show_all_locks = 0;
>  
> -	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, "o2dlm", uuid, "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);
> -		return;
> +		ret = open_debugfs_file(debugfs_path, "o2dlm", uuid,
> +					"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);
> +			return;
> +		}
> +	} else {
> +		file = fopen(path, "r");
> +		if (!file) {
> +			fprintf(stderr, "Could not open file at \"%s\"\n",
> +				path);
> +			return;
> +		}
>  	}
>  
>  	show_all_locks = list_empty(locklist);
> diff --git a/debugfs.ocfs2/include/dump_dlm_locks.h b/debugfs.ocfs2/include/dump_dlm_locks.h
> index 2cbb72a..7bc35ba 100644
> --- a/debugfs.ocfs2/include/dump_dlm_locks.h
> +++ b/debugfs.ocfs2/include/dump_dlm_locks.h
> @@ -74,7 +74,7 @@ struct lock {
>  	struct list_head list;
>  };
>  
> -void dump_dlm_locks(char *uuid, FILE *out, int dump_lvbs,
> +void dump_dlm_locks(char *uuid, FILE *out, char *path, int dump_lvbs,
>  		    struct list_head *locklist);
>  
>  #endif		/* _DUMP_DLM_LOCKS_H_ */