On Tue, 2016-07-19 at 15:25 +0200, Hannes Reinecke wrote: > For ZBC devices I/O must not cross zone boundaries, so setup > the 'chunk_sectors' block queue setting to the zone size. > This is only valid for REPORT ZONES SAME type 2 or 3; > for other types the zone sizes might be different > for individual zones. So issue a warning if the type is > found to be different. > Also the capacity might be different from the announced > capacity, so adjust it as needed. > > Signed-off-by: Hannes Reinecke <h...@suse.com>
... > +static void sd_read_zones(struct scsi_disk *sdkp, unsigned char *buffer) > +{ > + int retval; > + unsigned char *desc; > + u32 rep_len; > + u8 same; > + u64 zone_len, lba; > + > + if (sdkp->zoned != 1) > + /* Device managed, no special handling required */ > + return; > + > + retval = sd_zbc_report_zones(sdkp, buffer, SD_BUF_SIZE, > + 0, ZBC_ZONE_REPORTING_OPTION_ALL, false); > + if (retval < 0) > + return; > + > + rep_len = get_unaligned_be32(&buffer[0]); > + if (rep_len < 64) { > + sd_printk(KERN_WARNING, sdkp, > + "REPORT ZONES report invalid length %u\n", > + rep_len); > + return; > + } > + > + if (sdkp->rc_basis == 0) { > + /* The max_lba field is the capacity of a zoned device */ > + lba = get_unaligned_be64(&buffer[8]); > + if (lba + 1 > sdkp->capacity) { > + sd_printk(KERN_WARNING, sdkp, > + "Max LBA %zu (capacity %zu)\n", > + (sector_t) lba + 1, sdkp->capacity); > + sdkp->capacity = lba + 1; > + } > + } > + > + /* > + * Adjust 'chunk_sectors' to the zone length if the device > + * supports equal zone sizes. > + */ > + same = buffer[4] & 0xf; > + if (same == 0 || same > 3) { > + sd_printk(KERN_WARNING, sdkp, > + "REPORT ZONES SAME type %d not supported\n", same); > + return; > + } > + /* Read the zone length from the first zone descriptor */ > + desc = &buffer[64]; > + zone_len = logical_to_sectors(sdkp->device, > + get_unaligned_be64(&desc[8])); > + blk_queue_chunk_sectors(sdkp->disk->queue, zone_len); > +} > + So, blk_queue_chunk_sectors() has: void blk_queue_chunk_sectors(struct request_queue *q, unsigned int chunk_sectors) { BUG_ON(!is_power_of_2(chunk_sectors)); q->limits.chunk_sectors = chunk_sectors; } and it seems like if some device reports a non-power-of-2 zone_len then we will BUG_ON(). Probably would be better if we reported an error instead? -Ewan -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html