Commit 97c7e85c authored by Eric Blake's avatar Eric Blake Committed by Stefan Hajnoczi
Browse files

iscsi: Switch .bdrv_co_discard() to byte-based 



Another step towards killing off sector-based block APIs.

Unlike write_zeroes, where we can be handed unaligned requests
and must fail gracefully with -ENOTSUP for a fallback, we are
guaranteed that discard requests are always aligned because the
block layer already ignored unaligned head/tail.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1468624988-423-13-git-send-email-eblake@redhat.com
Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
parent 1014170b

block/iscsi.c

+8 −10
Original line number Diff line number Diff line
@@ -1042,24 +1042,21 @@ iscsi_getlength(BlockDriverState *bs) 
}



static int

coroutine_fn iscsi_co_discard(BlockDriverState *bs, int64_t sector_num,

                                   int nb_sectors)

coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, int count)

{

    IscsiLun *iscsilun = bs->opaque;

    struct IscsiTask iTask;

    struct unmap_list list;



    if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {

        return -EINVAL;

    }

    assert(is_byte_request_lun_aligned(offset, count, iscsilun));



    if (!iscsilun->lbp.lbpu) {

        /* UNMAP is not supported by the target */

        return 0;

    }



    list.lba = sector_qemu2lun(sector_num, iscsilun);

    list.num = sector_qemu2lun(nb_sectors, iscsilun);

    list.lba = offset / iscsilun->block_size;

    list.num = count / iscsilun->block_size;



    iscsi_co_init_iscsitask(iscsilun, &iTask);

retry:
@@ -1094,7 +1091,8 @@ retry: 
        return iTask.err_code;

    }



    iscsi_allocmap_set_invalid(iscsilun, sector_num, nb_sectors);

    iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,

                               count >> BDRV_SECTOR_BITS);



    return 0;

}
@@ -1998,7 +1996,7 @@ static BlockDriver bdrv_iscsi = { 
    .bdrv_refresh_limits = iscsi_refresh_limits,



    .bdrv_co_get_block_status = iscsi_co_get_block_status,

    .bdrv_co_discard      = iscsi_co_discard,

    .bdrv_co_pdiscard      = iscsi_co_pdiscard,

    .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,

    .bdrv_co_readv         = iscsi_co_readv,

    .bdrv_co_writev_flags  = iscsi_co_writev_flags,