[PATCH 4.18 015/197] bnxt_en: Do not adjust max_cp_rings by the ones used by RDMA.

From: Greg Kroah-Hartman
Date: Thu Sep 13 2018 - 09:50:52 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Michael Chan <michael.chan@xxxxxxxxxxxx>

[ Upstream commit 00fe9c326d2027f2437dea38ef0e82f9d02d94c0 ]

Currently, the driver adjusts the bp->hw_resc.max_cp_rings by the number
of MSIX vectors used by RDMA. There is one code path in open that needs
to check the true max_cp_rings including any used by RDMA. This code
is now checking for the reduced max_cp_rings which will fail when the
number of cp rings is very small.

To fix this in a clean way, we don't adjust max_cp_rings anymore.
Instead, we add a helper bnxt_get_max_func_cp_rings_for_en() to get the
reduced max_cp_rings when appropriate.

Fixes: ec86f14ea506 ("bnxt_en: Add ULP calls to stop and restart IRQs.")
Signed-off-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bnxt/bnxt.c | 7 ++++---
drivers/net/ethernet/broadcom/bnxt/bnxt.h | 2 +-
drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c | 7 ++++---
drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c | 5 -----
4 files changed, 9 insertions(+), 12 deletions(-)

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -5907,9 +5907,9 @@ unsigned int bnxt_get_max_func_cp_rings(
return bp->hw_resc.max_cp_rings;
}

-void bnxt_set_max_func_cp_rings(struct bnxt *bp, unsigned int max)
+unsigned int bnxt_get_max_func_cp_rings_for_en(struct bnxt *bp)
{
- bp->hw_resc.max_cp_rings = max;
+ return bp->hw_resc.max_cp_rings - bnxt_get_ulp_msix_num(bp);
}

static unsigned int bnxt_get_max_func_irqs(struct bnxt *bp)
@@ -8492,7 +8492,8 @@ static void _bnxt_get_max_rings(struct b

*max_tx = hw_resc->max_tx_rings;
*max_rx = hw_resc->max_rx_rings;
- *max_cp = min_t(int, hw_resc->max_irqs, hw_resc->max_cp_rings);
+ *max_cp = min_t(int, bnxt_get_max_func_cp_rings_for_en(bp),
+ hw_resc->max_irqs);
*max_cp = min_t(int, *max_cp, hw_resc->max_stat_ctxs);
max_ring_grps = hw_resc->max_hw_ring_grps;
if (BNXT_CHIP_TYPE_NITRO_A0(bp) && BNXT_PF(bp)) {
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1468,7 +1468,7 @@ int bnxt_hwrm_set_coal(struct bnxt *);
unsigned int bnxt_get_max_func_stat_ctxs(struct bnxt *bp);
void bnxt_set_max_func_stat_ctxs(struct bnxt *bp, unsigned int max);
unsigned int bnxt_get_max_func_cp_rings(struct bnxt *bp);
-void bnxt_set_max_func_cp_rings(struct bnxt *bp, unsigned int max);
+unsigned int bnxt_get_max_func_cp_rings_for_en(struct bnxt *bp);
int bnxt_get_avail_msix(struct bnxt *bp, int num);
int bnxt_reserve_rings(struct bnxt *bp);
void bnxt_tx_disable(struct bnxt *bp);
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_sriov.c
@@ -451,7 +451,7 @@ static int bnxt_hwrm_func_vf_resc_cfg(st

bnxt_hwrm_cmd_hdr_init(bp, &req, HWRM_FUNC_VF_RESOURCE_CFG, -1, -1);

- vf_cp_rings = hw_resc->max_cp_rings - bp->cp_nr_rings;
+ vf_cp_rings = bnxt_get_max_func_cp_rings_for_en(bp) - bp->cp_nr_rings;
vf_stat_ctx = hw_resc->max_stat_ctxs - bp->num_stat_ctxs;
if (bp->flags & BNXT_FLAG_AGG_RINGS)
vf_rx_rings = hw_resc->max_rx_rings - bp->rx_nr_rings * 2;
@@ -544,7 +544,8 @@ static int bnxt_hwrm_func_cfg(struct bnx
max_stat_ctxs = hw_resc->max_stat_ctxs;

/* Remaining rings are distributed equally amongs VF's for now */
- vf_cp_rings = (hw_resc->max_cp_rings - bp->cp_nr_rings) / num_vfs;
+ vf_cp_rings = (bnxt_get_max_func_cp_rings_for_en(bp) -
+ bp->cp_nr_rings) / num_vfs;
vf_stat_ctx = (max_stat_ctxs - bp->num_stat_ctxs) / num_vfs;
if (bp->flags & BNXT_FLAG_AGG_RINGS)
vf_rx_rings = (hw_resc->max_rx_rings - bp->rx_nr_rings * 2) /
@@ -638,7 +639,7 @@ static int bnxt_sriov_enable(struct bnxt
*/
vfs_supported = *num_vfs;

- avail_cp = hw_resc->max_cp_rings - bp->cp_nr_rings;
+ avail_cp = bnxt_get_max_func_cp_rings_for_en(bp) - bp->cp_nr_rings;
avail_stat = hw_resc->max_stat_ctxs - bp->num_stat_ctxs;
avail_cp = min_t(int, avail_cp, avail_stat);

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
@@ -169,7 +169,6 @@ static int bnxt_req_msix_vecs(struct bnx
edev->ulp_tbl[ulp_id].msix_requested = avail_msix;
}
bnxt_fill_msix_vecs(bp, ent);
- bnxt_set_max_func_cp_rings(bp, max_cp_rings - avail_msix);
edev->flags |= BNXT_EN_FLAG_MSIX_REQUESTED;
return avail_msix;
}
@@ -178,7 +177,6 @@ static int bnxt_free_msix_vecs(struct bn
{
struct net_device *dev = edev->net;
struct bnxt *bp = netdev_priv(dev);
- int max_cp_rings, msix_requested;

ASSERT_RTNL();
if (ulp_id != BNXT_ROCE_ULP)
@@ -187,9 +185,6 @@ static int bnxt_free_msix_vecs(struct bn
if (!(edev->flags & BNXT_EN_FLAG_MSIX_REQUESTED))
return 0;

- max_cp_rings = bnxt_get_max_func_cp_rings(bp);
- msix_requested = edev->ulp_tbl[ulp_id].msix_requested;
- bnxt_set_max_func_cp_rings(bp, max_cp_rings + msix_requested);
edev->ulp_tbl[ulp_id].msix_requested = 0;
edev->flags &= ~BNXT_EN_FLAG_MSIX_REQUESTED;
if (netif_running(dev)) {