On 2022/09/11 15:33, Sam Li wrote:
> Damien Le Moal <damien.lem...@opensource.wdc.com> 于2022年9月11日周日 13:31写道：
[...]
>>> +/*
>>> + * zone management operations - Execute an operation on a zone
>>> + */
>>> +static int coroutine_fn raw_co_zone_mgmt(BlockDriverState *bs, BlockZoneOp
>>> op,
>>> + int64_t offset, int64_t len) {
>>> +#if defined(CONFIG_BLKZONED)
>>> + BDRVRawState *s = bs->opaque;
>>> + RawPosixAIOData acb;
>>> + int64_t zone_sector, zone_sector_mask;
>>> + const char *zone_op_name;
>>> + unsigned long zone_op;
>>> + bool is_all = false;
>>> +
>>> + zone_sector = bs->bl.zone_sectors;
>>> + zone_sector_mask = zone_sector - 1;
>>> + if (offset & zone_sector_mask) {
>>> + error_report("sector offset %" PRId64 " is not aligned to zone
>>> size "
>>> + "%" PRId64 "", offset, zone_sector);
>>> + return -EINVAL;
>>> + }
>>> +
>>> + if (len & zone_sector_mask) {
>>
>> Linux allows SMR drives to have a smaller last zone. So this needs to be
>> accounted for here. Otherwise, a zone operation that includes the last
>> smaller
>> zone would always fail. Something like this would work:
>>
>> if (((offset + len) < capacity &&
>> len & zone_sector_mask) ||
>> offset + len > capacity) {
>>
>
> I see. I think the offset can be removed, like:
> if (((len < capacity && len & zone_sector_mask) || len > capacity) {
> Then if we use the previous zone's len for the last smaller zone, it
> will be greater than its capacity.
Nope, you cannot remove the offset since the zone operation may be for that last
zone only, that is, offset == last zone start and len == last zone smaller size.
In that case, len is alwats smaller than capacity.
>
> I will also include "opening the last zone" as a test case later.
Note that you can create such smaller last zone on the host with null_blk by
specifying a device capacity that is *not* a multiple of the zone size.
>
>>> + error_report("number of sectors %" PRId64 " is not aligned to zone
>>> size"
>>> + " %" PRId64 "", len, zone_sector);
>>> + return -EINVAL;
>>> + }
>>> +
>>> + switch (op) {
>>> + case BLK_ZO_OPEN:
>>> + zone_op_name = "BLKOPENZONE";
>>> + zone_op = BLKOPENZONE;
>>> + break;
>>> + case BLK_ZO_CLOSE:
>>> + zone_op_name = "BLKCLOSEZONE";
>>> + zone_op = BLKCLOSEZONE;
>>> + break;
>>> + case BLK_ZO_FINISH:
>>> + zone_op_name = "BLKFINISHZONE";
>>> + zone_op = BLKFINISHZONE;
>>> + break;
>>> + case BLK_ZO_RESET:
>>> + zone_op_name = "BLKRESETZONE";
>>> + zone_op = BLKRESETZONE;
>>> + break;
>>> + default:
>>> + g_assert_not_reached();
>>> + }
>>> +
>>> + acb = (RawPosixAIOData) {
>>> + .bs = bs,
>>> + .aio_fildes = s->fd,
>>> + .aio_type = QEMU_AIO_ZONE_MGMT,
>>> + .aio_offset = offset,
>>> + .aio_nbytes = len,
>>> + .zone_mgmt = {
>>> + .zone_op = zone_op,
>>> + .zone_op_name = zone_op_name,
>>> + .all = is_all,
>>> + },
>>> + };
>>> +
>>> + return raw_thread_pool_submit(bs, handle_aiocb_zone_mgmt, &acb);
>>> +#else
>>> + return -ENOTSUP;
>>> +#endif
>>> +}
--
Damien Le Moal
Western Digital Research
