kern/175323: Fail to use ZVOL as a gmirror component

[Алексей Волков]

The following reply was made to PR kern/175323; it has been noted by GNATS.

From: =?UTF-8?B?0JDQu9C10LrRgdC10Lkg0JLQvtC70LrQvtCy?=
 <Alexei.Volkov at softlynx.ru>
To: bug-followup at FreeBSD.org, Andriy Gapon <avg at FreeBSD.org>
Cc:  
Subject: Re: kern/175323: Fail to use ZVOL as a gmirror component
Date: Mon, 21 Jan 2013 15:47:32 +0400

 Andriy, many thanks for the suggestion. I am trying to rebuild and test
 the kernel with the following patch:
 
 --- sys/geom/mirror/g_mirror.c    (revision 245741)
 +++ sys/geom/mirror/g_mirror.c    (working copy)
 @@ -456,7 +456,7 @@
      disk->d_flags = md->md_dflags;
      error = g_getattr("GEOM::candelete", disk->d_consumer, &i);
      if (error != 0)
 -        goto fail;
 +        i=0;
      if (i)
          disk->d_flags |= G_MIRROR_DISK_FLAG_CANDELETE;
      if (md->md_provider[0] != '\0')
 
 
 It seems to correct if assume G_MIRROR_DISK_FLAG_CANDELETE is always off
 unless successfully reported by GEOM::candelete attribute.
 
 -- 
 Best regards
 
 
 21.01.2013 13:47, Andriy Gapon пишет:
 > This
 >> GEOM_MIRROR: Cannot add disk zvol/tank0/vol0 to mirror0 (error=45).
 > seems to be triggered by the following code in sys/geom/mirror/g_mirror.c:
 >
 > error = g_getattr("GEOM::candelete", disk->d_consumer, &i);
 > if (error != 0)
 >         goto fail;
 >
 > plus the fact that ZFS zvol does the following:
 > case BIO_GETATTR:
 > case BIO_DELETE:
 > default:
 >         g_io_deliver(bp, EOPNOTSUPP);
 >         break;
 >
 > Perhaps, the gmirror code should be more flexible with respect to EOPNOTSUPP
 > from g_getattr?
 >