On 5/26/17 11:13 AM, Eric Sandeen wrote:
> After the long discussion about warning the user and/or consumer
> of xfs_metadumps about dirty logs, it crossed my mind that we
> could use the reserved slot in the metadump header to tag the
> file with attributes, so the consumer of the metadump knows how
> it was created.
>
> This patch adds 4 flags to describe the metadump: The first simply
> indicates the presence of any (or no) informational flags.
> The old mb_reserved field has been 0 on disk since inception, so
> the presence of XFS_METADUMP_INFO_FLAGS indicates that this metadump
> may contain the informational flags:
>
> - dirty log
> - obfuscated
> - full blocks (unused portions of metadata blocks
> are not zeroed out).
>
> It then adds a new option to xfs_mdrestore, "-i" to show info,
> which can be used with or without a target file:
>
> # xfs_mdrestore -i metadumpfile
> metadumpfile: not obfuscated, clean log, full metadata blocks
>
> Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
> ---
>
> V2: rename to mb_info, add the "we have flags" flag
Ping, any thoughts on this V2?
> diff --git a/db/metadump.c b/db/metadump.c
> index fe068ef..2f5b5b5 100644
> --- a/db/metadump.c
> +++ b/db/metadump.c
> @@ -2820,6 +2820,28 @@ metadump_f(
> metablock->mb_blocklog = BBSHIFT;
> metablock->mb_magic = cpu_to_be32(XFS_MD_MAGIC);
>
> + /* Set flags about state of metadump */
> + metablock->mb_info = XFS_METADUMP_INFO_FLAGS;
> + if (obfuscate)
> + metablock->mb_info |= XFS_METADUMP_OBFUSCATED;
> + if (!zero_stale_data)
> + metablock->mb_info |= XFS_METADUMP_FULLBLOCKS;
> +
> + /* If we'll copy the log, see if the log is dirty */
> + if (mp->m_sb.sb_logstart) {
> + push_cur();
> + set_cur(&typtab[TYP_LOG],
> + XFS_FSB_TO_DADDR(mp, mp->m_sb.sb_logstart),
> + mp->m_sb.sb_logblocks * blkbb, DB_RING_IGN, NULL);
> + if (iocur_top->data) { /* best effort */
> + struct xlog log;
> +
> + if (xlog_is_dirty(mp, &log, &x, 0))
> + metablock->mb_info |= XFS_METADUMP_DIRTYLOG;
> + }
> + pop_cur();
> + }
> +
> block_index = (__be64 *)((char *)metablock + sizeof(xfs_metablock_t));
> block_buffer = (char *)metablock + BBSIZE;
> num_indices = (BBSIZE - sizeof(xfs_metablock_t)) / sizeof(__be64);
> diff --git a/include/xfs_metadump.h b/include/xfs_metadump.h
> index f4be51b..7f3039e 100644
> --- a/include/xfs_metadump.h
> +++ b/include/xfs_metadump.h
> @@ -25,8 +25,14 @@ typedef struct xfs_metablock {
> __be32 mb_magic;
> __be16 mb_count;
> __uint8_t mb_blocklog;
> - __uint8_t mb_reserved;
> + __uint8_t mb_info;
> /* followed by an array of xfs_daddr_t */
> } xfs_metablock_t;
>
> +/* These flags are informational only, not backwards compatible */
> +#define XFS_METADUMP_INFO_FLAGS (1 << 0) /* This image has informative flags */
> +#define XFS_METADUMP_OBFUSCATED (1 << 1)
> +#define XFS_METADUMP_FULLBLOCKS (1 << 2)
> +#define XFS_METADUMP_DIRTYLOG (1 << 3)
> +
> #endif /* _XFS_METADUMP_H_ */
> diff --git a/man/man8/xfs_mdrestore.8 b/man/man8/xfs_mdrestore.8
> index 2095f15..72f3b29 100644
> --- a/man/man8/xfs_mdrestore.8
> +++ b/man/man8/xfs_mdrestore.8
> @@ -4,11 +4,15 @@ xfs_mdrestore \- restores an XFS metadump image to a filesystem image
> .SH SYNOPSIS
> .B xfs_mdrestore
> [
> -.B \-g
> +.B \-gi
> ]
> .I source
> .I target
> .br
> +.B xfs_mdrestore
> +.B \-i
> +.I source
> +.br
> .B xfs_mdrestore \-V
> .SH DESCRIPTION
> .B xfs_mdrestore
> @@ -39,6 +43,12 @@ can be destroyed.
> .B \-g
> Shows restore progress on stdout.
> .TP
> +.B \-i
> +Shows metadump information on stdout. If no
> +.I target
> +is specified, exits after displaying information. Older metadumps man not
> +include any descriptive information.
> +.TP
> .B \-V
> Prints the version number and exits.
> .SH DIAGNOSTICS
> diff --git a/mdrestore/xfs_mdrestore.c b/mdrestore/xfs_mdrestore.c
> index 0d399f1..9d1b4e8 100644
> --- a/mdrestore/xfs_mdrestore.c
> +++ b/mdrestore/xfs_mdrestore.c
> @@ -21,6 +21,7 @@
>
> char *progname;
> int show_progress = 0;
> +int show_info = 0;
> int progress_since_warning = 0;
>
> static void
> @@ -213,11 +214,14 @@ main(
>
> progname = basename(argv[0]);
>
> - while ((c = getopt(argc, argv, "gV")) != EOF) {
> + while ((c = getopt(argc, argv, "giV")) != EOF) {
> switch (c) {
> case 'g':
> show_progress = 1;
> break;
> + case 'i':
> + show_info = 1;
> + break;
> case 'V':
> printf("%s version %s\n", progname, VERSION);
> exit(0);
> @@ -226,7 +230,11 @@ main(
> }
> }
>
> - if (argc - optind != 2)
> + if (argc - optind < 1 || argc - optind > 2)
> + usage();
> +
> + /* show_info without a target is ok */
> + if (!show_info && argc - optind != 2)
> usage();
>
> /* open source */
> @@ -239,6 +247,34 @@ main(
> if (src_f == NULL)
> fatal("cannot open source dump file\n");
> }
> +
> + if (show_info) {
> + xfs_metablock_t mb;
> +
> + if (fread(&mb, sizeof(mb), 1, src_f) != 1)
> + fatal("error reading from file: %s\n", strerror(errno));
> +
> + if (be32_to_cpu(mb.mb_magic) != XFS_MD_MAGIC)
> + fatal("specified file is not a metadata dump\n");
> +
> + if (mb.mb_info & XFS_METADUMP_INFO_FLAGS) {
> + printf("%s: %sobfuscated, %s log, %s metadata blocks\n",
> + argv[optind],
> + mb.mb_info & XFS_METADUMP_OBFUSCATED ? "":"not ",
> + mb.mb_info & XFS_METADUMP_DIRTYLOG ? "dirty":"clean",
> + mb.mb_info & XFS_METADUMP_FULLBLOCKS ? "full":"zeroed");
> + } else {
> + printf("%s: no informational flags present\n",
> + argv[optind]);
> + }
> +
> + if (argc - optind == 1)
> + exit(0);
> +
> + /* Go back to the beginning for the restore function */
> + fseek(src_f, 0L, SEEK_SET);
> + }
> +
> optind++;
>
> /* check and open target */
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
--
To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
