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 <[email protected]>
> ---
> 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 ?
> + 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;
> + 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,
};
> +
> + 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
