IB/iser: Fix sg_tablesize calculation

For devices that can register page list that is bigger than
USHRT_MAX, we actually take the wrong value for sg_tablesize.
E.g: for CX4 max_fast_reg_page_list_len is 65536 (bigger than USHRT_MAX)
so we set sg_tablesize to 0 by mistake. Therefore, each IO that is
bigger than 4k splitted to "< 4k" chunks that cause performance degredation.
Remove wrong sg_tablesize assignment, and use the value that was set during
address resolution handler with the needed casting.

Cc: <stable@vger.kernel.org> # v4.5+
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Max Gurtovoy 2017-01-18 00:40:39 +02:00 committed by Doug Ledford
parent 0a475ef422
commit 1e5db6c31a
1 changed files with 0 additions and 7 deletions

View File

@ -651,13 +651,6 @@ iscsi_iser_session_create(struct iscsi_endpoint *ep,
SHOST_DIX_GUARD_CRC);
}
/*
* Limit the sg_tablesize and max_sectors based on the device
* max fastreg page list length.
*/
shost->sg_tablesize = min_t(unsigned short, shost->sg_tablesize,
ib_conn->device->ib_device->attrs.max_fast_reg_page_list_len);
if (iscsi_host_add(shost,
ib_conn->device->ib_device->dma_device)) {
mutex_unlock(&iser_conn->state_mutex);