diff options
Diffstat (limited to 'drivers/infiniband/ulp/iser/iser_verbs.c')
| -rw-r--r-- | drivers/infiniband/ulp/iser/iser_verbs.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c index 56b7240a3fc3..616d978cbf2b 100644 --- a/drivers/infiniband/ulp/iser/iser_verbs.c +++ b/drivers/infiniband/ulp/iser/iser_verbs.c @@ -703,19 +703,34 @@ iser_calc_scsi_params(struct iser_conn *iser_conn, unsigned int max_sectors) { struct iser_device *device = iser_conn->ib_conn.device; + struct ib_device_attr *attr = &device->ib_device->attrs; unsigned short sg_tablesize, sup_sg_tablesize; + unsigned short reserved_mr_pages; + + /* + * FRs without SG_GAPS or FMRs can only map up to a (device) page per + * entry, but if the first entry is misaligned we'll end up using two + * entries (head and tail) for a single page worth data, so one + * additional entry is required. + */ + if ((attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) && + (attr->device_cap_flags & IB_DEVICE_SG_GAPS_REG)) + reserved_mr_pages = 0; + else + reserved_mr_pages = 1; sg_tablesize = DIV_ROUND_UP(max_sectors * 512, SIZE_4K); - if (device->ib_device->attrs.device_cap_flags & - IB_DEVICE_MEM_MGT_EXTENSIONS) + if (attr->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS) sup_sg_tablesize = min_t( uint, ISCSI_ISER_MAX_SG_TABLESIZE, - device->ib_device->attrs.max_fast_reg_page_list_len); + attr->max_fast_reg_page_list_len - reserved_mr_pages); else sup_sg_tablesize = ISCSI_ISER_MAX_SG_TABLESIZE; iser_conn->scsi_sg_tablesize = min(sg_tablesize, sup_sg_tablesize); + iser_conn->pages_per_mr = + iser_conn->scsi_sg_tablesize + reserved_mr_pages; } /** |