ice: add bitmap to track VF MSI-X usage

Create a bitamp to track MSI-X usage for VFs. The bitmap has the size of
total MSI-X amount on device, because at init time the amount of MSI-X
used by VFs isn't known.

The bitmap is used in follow up patchset to provide a block of
continuous block of MSI-X indexes for each created VF.
Signed-off-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Tested-by: Rafal Romanowski <rafal.romanowski@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/intel/ice/ice.h

@@ -554,6 +554,8 @@ struct ice_pf {
 	 * MSIX vectors allowed on this PF.
 	 */
 	u16 sriov_base_vector;
+	unsigned long *sriov_irq_bm;	/* bitmap to track irq usage */
+	u16 sriov_irq_size;		/* size of the irq_bm bitmap */
 
 	u16 ctrl_vsi_idx;		/* control VSI index in pf->vsi array */
 

drivers/net/ethernet/intel/ice/ice_sriov.c

@@ -138,6 +138,8 @@ static int ice_sriov_free_msix_res(struct ice_pf *pf)
 	if (!pf)
 		return -EINVAL;
 
+	bitmap_free(pf->sriov_irq_bm);
+	pf->sriov_irq_size = 0;
 	pf->sriov_base_vector = 0;
 
 	return 0;
@@ -853,10 +855,16 @@ static int ice_create_vf_entries(struct ice_pf *pf, u16 num_vfs)
  */
 static int ice_ena_vfs(struct ice_pf *pf, u16 num_vfs)
 {
+	int total_vectors = pf->hw.func_caps.common_cap.num_msix_vectors;
 	struct device *dev = ice_pf_to_dev(pf);
 	struct ice_hw *hw = &pf->hw;
 	int ret;
 
+	pf->sriov_irq_bm = bitmap_zalloc(total_vectors, GFP_KERNEL);
+	if (!pf->sriov_irq_bm)
+		return -ENOMEM;
+	pf->sriov_irq_size = total_vectors;
+
 	/* Disable global interrupt 0 so we don't try to handle the VFLR. */
 	wr32(hw, GLINT_DYN_CTL(pf->oicr_irq.index),
 	     ICE_ITR_NONE << GLINT_DYN_CTL_ITR_INDX_S);
@@ -915,6 +923,7 @@ static int ice_ena_vfs(struct ice_pf *pf, u16 num_vfs)
 	/* rearm interrupts here */
 	ice_irq_dynamic_ena(hw, NULL, NULL);
 	clear_bit(ICE_OICR_INTR_DIS, pf->state);
+	bitmap_free(pf->sriov_irq_bm);
 	return ret;
 }