libblkid: support zone reset for wipefs

We cannot overwrite superblock magic in a sequential required zone. So,
wipefs cannot work as it is. Instead, this commit implements the wiping by
zone resetting.

Zone resetting must be done only for a sequential write zone. This is
checked by is_conventional().

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>

diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
index 219cceea0f947087d7df648056a45ec27050f29f..d4ca47c6dbedde4e82fc424467b40c82e74af0f1 100644 (file)
--- a/libblkid/src/probe.c
+++ b/libblkid/src/probe.c
@@ -1229,6 +1229,39 @@ int blkid_do_probe(blkid_probe pr)
        return rc;
 }
 
+#ifdef HAVE_LINUX_BLKZONED_H
+static int is_conventional(blkid_probe pr, uint64_t offset)
+{
+       struct blk_zone_report *rep = NULL;
+       int ret;
+       uint64_t zone_mask;
+
+       if (!pr->zone_size)
+               return 1;
+
+       zone_mask = ~(pr->zone_size - 1);
+       rep = blkdev_get_zonereport(blkid_probe_get_fd(pr),
+                                   (offset & zone_mask) >> 9, 1);
+       if (!rep)
+               return -1;
+
+       if (rep->zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL)
+               ret = 1;
+       else
+               ret = 0;
+
+       free(rep);
+
+       return ret;
+}
+#else
+static inline int is_conventional(blkid_probe pr __attribute__((__unused__)),
+                                 uint64_t offset __attribute__((__unused__)))
+{
+       return 1;
+}
+#endif
+
 /**
  * blkid_do_wipe:
  * @pr: prober
@@ -1268,6 +1301,7 @@ int blkid_do_wipe(blkid_probe pr, int dryrun)
        const char *off = NULL;
        size_t len = 0;
        uint64_t offset, magoff;
+       int conventional;
        char buf[BUFSIZ];
        int fd, rc = 0;
        struct blkid_chain *chn;
@@ -1303,6 +1337,11 @@ int blkid_do_wipe(blkid_probe pr, int dryrun)
        if (len > sizeof(buf))
                len = sizeof(buf);
 
+       rc = is_conventional(pr, offset);
+       if (rc < 0)
+               return rc;
+       conventional = rc == 1;
+
        DBG(LOWPROBE, ul_debug(
            "do_wipe [offset=0x%"PRIx64" (%"PRIu64"), len=%zu, chain=%s, idx=%d, dryrun=%s]\n",
            offset, offset, len, chn->driver->name, chn->idx, dryrun ? "yes" : "not"));
@@ -1310,13 +1349,31 @@ int blkid_do_wipe(blkid_probe pr, int dryrun)
        if (lseek(fd, offset, SEEK_SET) == (off_t) -1)
                return -1;
 
-       memset(buf, 0, len);
-
        if (!dryrun && len) {
-               /* wipen on device */
-               if (write_all(fd, buf, len))
-                       return -1;
-               fsync(fd);
+               if (conventional) {
+                       memset(buf, 0, len);
+
+                       /* wipen on device */
+                       if (write_all(fd, buf, len))
+                               return -1;
+                       fsync(fd);
+               } else {
+#ifdef HAVE_LINUX_BLKZONED_H
+                       uint64_t zone_mask = ~(pr->zone_size - 1);
+                       struct blk_zone_range range = {
+                               .sector = (offset & zone_mask) >> 9,
+                               .nr_sectors = pr->zone_size >> 9,
+                       };
+
+                       rc = ioctl(fd, BLKRESETZONE, &range);
+                       if (rc < 0)
+                               return -1;
+#else
+                       /* Should not reach here */
+                       assert(0);
+#endif
+               }
+
                pr->flags &= ~BLKID_FL_MODIF_BUFF;      /* be paranoid */
 
                return blkid_probe_step_back(pr);