When running the partition table probes, the code considered empty
tables as invalid ones. Because of this, kpartx -u / -d does not work
correctly on empty tables (with zero partitions).

The return value of the probes should be:
-1: not our partition table type
0: our partition table, but no partitions exist
>0: number of partitions found

Adapt read_gpt_pt() to this semantics.

CC: Hannes Reinecke <hare@suse.com>
CC: Christophe Varoqui <christophe.varoqui@gmail.com>

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>
---
kpartx/gpt.c | 6 +++---
kpartx/kpartx.c | 6 ++----
2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/kpartx/gpt.c b/kpartx/gpt.c
index 3082cae..18be035 100644
--- a/kpartx/gpt.c
+++ b/kpartx/gpt.c
@@ -625,8 +625,8 @@ find_valid_gpt(int fd, gpt_header ** gpt, gpt_entry ** ptes)
* @fd
* @all - slice with start/size of whole disk
*
- * 0 if this isn't our partition table
- * number of partitions if successful
+ * -1 if this isn't our partition table
+ * number of partitions if successful (>= 0)
*
*/
int
@@ -643,7 +643,7 @@ read_gpt_pt (int fd, struct slice all, struct slice *sp, int ns)
free (gpt);
if (ptes)
free (ptes);
- return 0;
+ return -1;
}

for (i = 0; i < __le32_to_cpu(gpt->num_partition_entries) && i < ns; i++) {
diff --git a/kpartx/kpartx.c b/kpartx/kpartx.c
index b5e0a32..9a4c694 100644
--- a/kpartx/kpartx.c
+++ b/kpartx/kpartx.c
@@ -368,12 +368,10 @@ main(int argc, char **argv){
/* here we get partitions */
n = ptp->fn(fd, all, slices, SIZE(slices));

+ if (n >= 0) {
#ifdef DEBUG
- if (n >= 0)
printf("%s: %d slices
", ptp->type, n);
#endif
-
- if (n > 0) {
close(fd);
fd = -1;
}
@@ -607,7 +605,7 @@ main(int argc, char **argv){
break;

}
- if (n > 0)
+ if (n >= 0)
break;
}
if (what == LIST && loopcreated && S_ISREG (buf.st_mode)) {
--
1.7.7

--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel