On Tue, Apr 13, 2021 at 10:47:00PM +0000, Damien Le Moal wrote:
> On 2021/04/14 7:11, Naohiro Aota wrote:
> > 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.a...@wdc.com>
> > ---
> > libblkid/src/probe.c | 65 ++++++++++++++++++++++++++++++++++++++++----
> > 1 file changed, 59 insertions(+), 6 deletions(-)
> >
> > diff --git a/libblkid/src/probe.c b/libblkid/src/probe.c
> > index 102766e57aa0..7454a14bdfe6 100644
> > --- a/libblkid/src/probe.c
> > +++ b/libblkid/src/probe.c
> > @@ -107,6 +107,7 @@
> > #include <stdint.h>
> > #include <stdarg.h>
> > #include <limits.h>
> > +#include <stdbool.h>
> >
> > #include "blkidP.h"
> > #include "all-io.h"
> > @@ -1225,6 +1226,40 @@ int blkid_do_probe(blkid_probe pr)
> > return rc;
> > }
> >
> > +static int is_conventional(blkid_probe pr, uint64_t offset)
> > +{
> > + struct blk_zone_report *rep = NULL;
> > + size_t rep_size;
> > + bool conventional;
> > + int ret;
> > +
> > + if (!pr->zone_size)
> > + return 1;
> > +
> > + rep_size = sizeof(struct blk_zone_report) + sizeof(struct blk_zone);
> > + rep = malloc(rep_size);
> > + if (!rep)
> > + return -1;
> > +
> > + memset(rep, 0, rep_size);
>
> Use calloc() to get the zeroing done at the same time as allocation, may be ?
Will do.
> > + rep->sector = (offset & pr->zone_size) >> 9;
>
> Why the "& pr->zone_size" ? This seems wrong. To get the zone info of the zone
> containing offset, you can just have:
>
> rep->sector = offset >> 9;
>
> And if you want to align to the zone start, then:
>
> rep->sector = (offset & (~(pr->zone_size - 1))) >> 9;
Ouch. I was silly and missed this bug because it was only doing reset
on zone #0 and #1. I'll introduce "zone_mask" and do the correct
calculation.
> > + rep->nr_zones = 1;
> > + ret = ioctl(blkid_probe_get_fd(pr), BLKREPORTZONE, rep);
> > + if (ret) {
> > + free(rep);
> > + return -1;
> > + }
> > +
> > + if (rep->zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL)
> > + ret = 1;
> > + else
> > + ret = 0;
> > +
> > + free(rep);
> > +
> > + return ret;
> > +}
> > +
> > /**
> > * blkid_do_wipe:
> > * @pr: prober
> > @@ -1264,6 +1299,7 @@ int blkid_do_wipe(blkid_probe pr, int dryrun)
> > const char *off = NULL;
> > size_t len = 0;
> > uint64_t offset, magoff;
> > + bool conventional;
> > char buf[BUFSIZ];
> > int fd, rc = 0;
> > struct blkid_chain *chn;
> > @@ -1299,6 +1335,11 @@ 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"));
> > @@ -1306,13 +1347,25 @@ 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 {
> > + struct blk_zone_range range = {
> > + (offset & pr->zone_size) >> 9,
> > + pr->zone_size >> 9,
> > + };
>
> Please add the field names for clarity and fix the sector position (it looks
> very wrong):
>
> struct blk_zone_range range = {
> .sector = (offset & (~(pr->zone_size - 1))) >> 9,
> .nr_sectors = pr->zone_size >> 9,
> };
Will do the same.
> > +
> > + rc = ioctl(fd, BLKRESETZONE, &range);
> > + if (rc < 0)
> > + return -1;
> > + }
> > +
> > pr->flags &= ~BLKID_FL_MODIF_BUFF; /* be paranoid */
> >
> > return blkid_probe_step_back(pr);
> >
>
>
> --
> Damien Le Moal
> Western Digital Research
