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
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 */
--
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