sfc: Retry MCDI after NO_EVB_PORT error on a VF

After reboot the vswitch configuration from the PF may not be
complete before the VF attempts to restore filters. In that
case we see NO_EVB_PORT errors from the MC. Retry up to a time
limit or until a different result is seen.

Signed-off-by: Bert Kenward <bkenward@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c
index 41fb6b60a3f07e11444e0d62430aca937f7e84ea..2509ca916880b968aa84994423e9834f82599aa8 100644 (file)
--- a/drivers/net/ethernet/sfc/mcdi.c
+++ b/drivers/net/ethernet/sfc/mcdi.c
@@ -315,6 +315,7 @@ static void efx_mcdi_read_response_header(struct efx_nic *efx)
        }
 #endif
 
+       mcdi->resprc_raw = 0;
        if (error && mcdi->resp_data_len == 0) {
                netif_err(efx, hw, efx->net_dev, "MC rebooted\n");
                mcdi->resprc = -EIO;
@@ -325,8 +326,8 @@ static void efx_mcdi_read_response_header(struct efx_nic *efx)
                mcdi->resprc = -EIO;
        } else if (error) {
                efx->type->mcdi_read_response(efx, &hdr, mcdi->resp_hdr_len, 4);
-               mcdi->resprc =
-                       efx_mcdi_errno(EFX_DWORD_FIELD(hdr, EFX_DWORD_0));
+               mcdi->resprc_raw = EFX_DWORD_FIELD(hdr, EFX_DWORD_0);
+               mcdi->resprc = efx_mcdi_errno(mcdi->resprc_raw);
        } else {
                mcdi->resprc = 0;
        }
@@ -623,7 +624,8 @@ efx_mcdi_check_supported(struct efx_nic *efx, unsigned int cmd, size_t inlen)
 
 static int _efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
                                efx_dword_t *outbuf, size_t outlen,
-                               size_t *outlen_actual, bool quiet)
+                               size_t *outlen_actual, bool quiet,
+                               int *raw_rc)
 {
        struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
        MCDI_DECLARE_BUF_ERR(errbuf);
@@ -669,6 +671,8 @@ static int _efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
                 * acquiring the iface_lock. */
                spin_lock_bh(&mcdi->iface_lock);
                rc = mcdi->resprc;
+               if (raw_rc)
+                       *raw_rc = mcdi->resprc_raw;
                hdr_len = mcdi->resp_hdr_len;
                data_len = mcdi->resp_data_len;
                err_len = min(sizeof(errbuf), data_len);
@@ -708,27 +712,92 @@ static int _efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
 static int _efx_mcdi_rpc(struct efx_nic *efx, unsigned cmd,
                         const efx_dword_t *inbuf, size_t inlen,
                         efx_dword_t *outbuf, size_t outlen,
-                        size_t *outlen_actual, bool quiet)
+                        size_t *outlen_actual, bool quiet, int *raw_rc)
 {
        int rc;
 
        rc = efx_mcdi_rpc_start(efx, cmd, inbuf, inlen);
-       if (rc) {
-               if (outlen_actual)
-                       *outlen_actual = 0;
+       if (rc)
                return rc;
-       }
+
        return _efx_mcdi_rpc_finish(efx, cmd, inlen, outbuf, outlen,
-                                   outlen_actual, quiet);
+                                   outlen_actual, quiet, raw_rc);
 }
 
+static int _efx_mcdi_rpc_evb_retry(struct efx_nic *efx, unsigned cmd,
+                                  const efx_dword_t *inbuf, size_t inlen,
+                                  efx_dword_t *outbuf, size_t outlen,
+                                  size_t *outlen_actual, bool quiet)
+{
+       int raw_rc = 0;
+       int rc;
+
+       rc = _efx_mcdi_rpc(efx, cmd, inbuf, inlen,
+                          outbuf, outlen, outlen_actual, true, &raw_rc);
+
+       if ((rc == -EPROTO) && (raw_rc == MC_CMD_ERR_NO_EVB_PORT) &&
+           efx->type->is_vf) {
+               /* If the EVB port isn't available within a VF this may
+                * mean the PF is still bringing the switch up. We should
+                * retry our request shortly.
+                */
+               unsigned long abort_time = jiffies + MCDI_RPC_TIMEOUT;
+               unsigned int delay_us = 10000;
+
+               netif_dbg(efx, hw, efx->net_dev,
+                         "%s: NO_EVB_PORT; will retry request\n",
+                         __func__);
+
+               do {
+                       usleep_range(delay_us, delay_us + 10000);
+                       rc = _efx_mcdi_rpc(efx, cmd, inbuf, inlen,
+                                          outbuf, outlen, outlen_actual,
+                                          true, &raw_rc);
+                       if (delay_us < 100000)
+                               delay_us <<= 1;
+               } while ((rc == -EPROTO) &&
+                        (raw_rc == MC_CMD_ERR_NO_EVB_PORT) &&
+                        time_before(jiffies, abort_time));
+       }
+
+       if (rc && !quiet && !(cmd == MC_CMD_REBOOT && rc == -EIO))
+               efx_mcdi_display_error(efx, cmd, inlen,
+                                      outbuf, outlen, rc);
+
+       return rc;
+}
+
+/**
+ * efx_mcdi_rpc - Issue an MCDI command and wait for completion
+ * @efx: NIC through which to issue the command
+ * @cmd: Command type number
+ * @inbuf: Command parameters
+ * @inlen: Length of command parameters, in bytes.  Must be a multiple
+ *     of 4 and no greater than %MCDI_CTL_SDU_LEN_MAX_V1.
+ * @outbuf: Response buffer.  May be %NULL if @outlen is 0.
+ * @outlen: Length of response buffer, in bytes.  If the actual
+ *     response is longer than @outlen & ~3, it will be truncated
+ *     to that length.
+ * @outlen_actual: Pointer through which to return the actual response
+ *     length.  May be %NULL if this is not needed.
+ *
+ * This function may sleep and therefore must be called in an appropriate
+ * context.
+ *
+ * Return: A negative error code, or zero if successful.  The error
+ *     code may come from the MCDI response or may indicate a failure
+ *     to communicate with the MC.  In the former case, the response
+ *     will still be copied to @outbuf and *@outlen_actual will be
+ *     set accordingly.  In the latter case, *@outlen_actual will be
+ *     set to zero.
+ */
 int efx_mcdi_rpc(struct efx_nic *efx, unsigned cmd,
                 const efx_dword_t *inbuf, size_t inlen,
                 efx_dword_t *outbuf, size_t outlen,
                 size_t *outlen_actual)
 {
-       return _efx_mcdi_rpc(efx, cmd, inbuf, inlen, outbuf, outlen,
-                            outlen_actual, false);
+       return _efx_mcdi_rpc_evb_retry(efx, cmd, inbuf, inlen, outbuf, outlen,
+                                      outlen_actual, false);
 }
 
 /* Normally, on receiving an error code in the MCDI response,
@@ -744,8 +813,8 @@ int efx_mcdi_rpc_quiet(struct efx_nic *efx, unsigned cmd,
                       efx_dword_t *outbuf, size_t outlen,
                       size_t *outlen_actual)
 {
-       return _efx_mcdi_rpc(efx, cmd, inbuf, inlen, outbuf, outlen,
-                            outlen_actual, true);
+       return _efx_mcdi_rpc_evb_retry(efx, cmd, inbuf, inlen, outbuf, outlen,
+                                      outlen_actual, true);
 }
 
 int efx_mcdi_rpc_start(struct efx_nic *efx, unsigned cmd,
@@ -866,7 +935,7 @@ int efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
                        size_t *outlen_actual)
 {
        return _efx_mcdi_rpc_finish(efx, cmd, inlen, outbuf, outlen,
-                                   outlen_actual, false);
+                                   outlen_actual, false, NULL);
 }
 
 int efx_mcdi_rpc_finish_quiet(struct efx_nic *efx, unsigned cmd, size_t inlen,
@@ -874,7 +943,7 @@ int efx_mcdi_rpc_finish_quiet(struct efx_nic *efx, unsigned cmd, size_t inlen,
                              size_t *outlen_actual)
 {
        return _efx_mcdi_rpc_finish(efx, cmd, inlen, outbuf, outlen,
-                                   outlen_actual, true);
+                                   outlen_actual, true, NULL);
 }
 
 void efx_mcdi_display_error(struct efx_nic *efx, unsigned cmd,

diff --git a/drivers/net/ethernet/sfc/mcdi.h b/drivers/net/ethernet/sfc/mcdi.h
index 025d504c472b5e4ff0bfc516162e69926f65ede6..397660d1b3de0b809b274137a583901a91e097d9 100644 (file)
--- a/drivers/net/ethernet/sfc/mcdi.h
+++ b/drivers/net/ethernet/sfc/mcdi.h
@@ -71,6 +71,7 @@ struct efx_mcdi_iface {
        unsigned int credits;
        unsigned int seqno;
        int resprc;
+       int resprc_raw;
        size_t resp_hdr_len;
        size_t resp_data_len;
        spinlock_t async_lock;