Re: [PATCH 1/4] mdadm: bad block support for external metadata - initialization

[Tomasz Majchrzak <tomasz.majchrzak@intel.com>]

I cannot see how badblocks program is related to this patch. It is a generic
code for bad blocks support in IMSM metadata. It introduces 64-bit value for
sector address, the same size as in kernel. All it does is syncing kernel bad
block list with raid metadata.

Tomek

On Thu, Oct 20, 2016 at 04:02:20PM +0200, keld@keldix.com wrote:
> Is this safe for 2TB+ arrays?
> I think the badblocks program does not handle 2TB+ partitions?
> 
> best regards
> Keld
> 
> Best regards
> Keld
> 
> On Thu, Oct 20, 2016 at 03:03:46PM +0200, Tomasz Majchrzak wrote:
> > If metadata handler provides support for bad blocks, tell md by writing
> > 'external_bbl' to rdev state file (both on create and assemble),
> > followed by a list of known bad blocks written via sysfs 'bad_blocks'
> > file.
> > 
> > Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
> > Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
> > ---
> >  mdadm.h | 13 +++++++++++++
> >  sysfs.c | 29 ++++++++++++++++++++++++++++-
> >  2 files changed, 41 insertions(+), 1 deletion(-)
> > 
> > diff --git a/mdadm.h b/mdadm.h
> > index 0516c82..5156ea4 100755
> > --- a/mdadm.h
> > +++ b/mdadm.h
> > @@ -237,6 +237,17 @@ struct dlm_lksb {
> >  
> >  extern const char Name[];
> >  
> > +struct md_bb_entry {
> > +	unsigned long long sector;
> > +	int length;
> > +};
> > +
> > +struct md_bb {
> > +	int supported;
> > +	int count;
> > +	struct md_bb_entry *entries;
> > +};
> > +
> >  /* general information that might be extracted from a superblock */
> >  struct mdinfo {
> >  	mdu_array_info_t	array;
> > @@ -311,6 +322,8 @@ struct mdinfo {
> >  
> >  	/* info read from sysfs */
> >  	char		sysfs_array_state[20];
> > +
> > +	struct md_bb bb;
> >  };
> >  
> >  struct createinfo {
> > diff --git a/sysfs.c b/sysfs.c
> > index d28e21a..c7a8e66 100644
> > --- a/sysfs.c
> > +++ b/sysfs.c
> > @@ -50,8 +50,12 @@ void sysfs_free(struct mdinfo *sra)
> >  		while (sra->devs) {
> >  			struct mdinfo *d = sra->devs;
> >  			sra->devs = d->next;
> > +			if (d->bb.entries)
> > +				free(d->bb.entries);
> >  			free(d);
> >  		}
> > +		if (sra->bb.entries)
> > +			free(sra->bb.entries);
> >  		free(sra);
> >  		sra = sra2;
> >  	}
> > @@ -259,7 +263,7 @@ struct mdinfo *sysfs_read(int fd, char *devnm, unsigned long options)
> >  		dbase = base + strlen(base);
> >  		*dbase++ = '/';
> >  
> > -		dev = xmalloc(sizeof(*dev));
> > +		dev = xcalloc(1, sizeof(*dev));
> >  
> >  		/* Always get slot, major, minor */
> >  		strcpy(dbase, "slot");
> > @@ -687,6 +691,7 @@ int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume)
> >  	char nm[PATH_MAX];
> >  	char *dname;
> >  	int rv;
> > +	int i;
> >  
> >  	sprintf(dv, "%d:%d", sd->disk.major, sd->disk.minor);
> >  	rv = sysfs_set_str(sra, NULL, "new_dev", dv);
> > @@ -718,6 +723,28 @@ int sysfs_add_disk(struct mdinfo *sra, struct mdinfo *sd, int resume)
> >  		if (resume)
> >  			sysfs_set_num(sra, sd, "recovery_start", sd->recovery_start);
> >  	}
> > +	if (sd->bb.supported) {
> > +		if (sysfs_set_str(sra, sd, "state", "external_bbl")) {
> > +			/*
> > +			 * backward compatibility - if kernel doesn't support
> > +			 * bad blocks for external metadata, let it continue
> > +			 * as long as there are none known so far
> > +			 */
> > +			if (sd->bb.count) {
> > +				pr_err("The kernel has no support for bad blocks in external metadata\n");
> > +				return -1;
> > +			}
> > +		}
> > +
> > +		for (i = 0; i < sd->bb.count; i++) {
> > +			char s[30];
> > +			const struct md_bb_entry *entry = &sd->bb.entries[i];
> > +
> > +			snprintf(s, sizeof(s) - 1, "%llu %d\n", entry->sector,
> > +				 entry->length);
> > +			rv |= sysfs_set_str(sra, sd, "bad_blocks", s);
> > +		}
> > +	}
> >  	return rv;
> >  }
> >  
> > -- 
> > 1.8.3.1
> > 
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html