s390/qeth: allow cmd callbacks to return errnos

Error propagation from cmd callbacks currently works in a way where
qeth_send_control_data_cb() picks the raw HW code from the response,
and the cmd's originator later translates this into an errno.
The callback itself only returns 0 ("done") or 1 ("expect more data").

This is
1. limiting, as the only means for the callback to report an internal
error is to invent pseudo HW codes (such as IPA_RC_ENOMEM), that
the originator then needs to understand. For non-IPA callbacks, we
even provide a separate field in the IO buffer metadata (iob->rc) so
the callback can pass back a return value.
2. fragile, as the originator must take care to not translate any errno
that is returned by qeth's own IO code paths (eg -ENOMEM). Also, any
originator that forgets to translate the HW codes potentially passes
garbage back to its caller. For instance, see
commit 2aa4867198c2 ("s390/qeth: translate SETVLAN/DELVLAN errors").

Introduce a new model where all HW error translation is done within the
callback, and the callback returns
>  0, if it expects more data (as before)
== 0, on success
<  0, with an errno

Start off with converting all callbacks to the new model that either
a) pass back pseudo HW codes, or b) have a dependency on a specific
HW error code. Also convert c) the one callback that uses iob->rc, and
d) qeth_setadpparms_change_macaddr_cb() so that it can pass back an
error back to qeth_l2_request_initial_mac() even when the cmd itself
was successful.

The old model remains supported: if the callback returns 0, we still
propagate the response's HW error code back to the originator.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index 83f710336685a1e478594efb75219b7e3d56e8e3..18696ffb662d2b5e127b852a77b77b0b13be8f0e 100644 (file)
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -597,7 +597,6 @@ struct qeth_cmd_buffer {
        struct qeth_channel *channel;
        struct qeth_reply *reply;
        unsigned char *data;
-       int rc;
        void (*callback)(struct qeth_card *card, struct qeth_channel *channel,
                         struct qeth_cmd_buffer *iob);
 };

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index b1a7a35a086ead5b242657c88f5da53c71df5161..cdb65ba99888f3e82f5781d3479c512796d246e4 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -747,7 +747,6 @@ void qeth_release_buffer(struct qeth_channel *channel,
                qeth_put_reply(iob->reply);
                iob->reply = NULL;
        }
-       iob->rc = 0;
        spin_unlock_irqrestore(&channel->iob_lock, flags);
        wake_up(&channel->wait_q);
 }
@@ -809,7 +808,6 @@ static void qeth_send_control_data_cb(struct qeth_card *card,
        struct qeth_reply *reply = NULL;
        struct qeth_reply *r;
        unsigned long flags;
-       int keep_reply = 0;
        int rc = 0;
 
        QETH_CARD_TEXT(card, 4, "sndctlcb");
@@ -857,22 +855,27 @@ static void qeth_send_control_data_cb(struct qeth_card *card,
        if (!reply)
                goto out;
 
-       if (reply->callback) {
+       if (!reply->callback) {
+               rc = 0;
+       } else {
                if (cmd) {
                        reply->offset = (u16)((char *)cmd - (char *)iob->data);
-                       keep_reply = reply->callback(card, reply,
-                                                    (unsigned long)cmd);
-               } else
-                       keep_reply = reply->callback(card, reply,
-                                                    (unsigned long)iob);
+                       rc = reply->callback(card, reply, (unsigned long)cmd);
+               } else {
+                       rc = reply->callback(card, reply, (unsigned long)iob);
+               }
        }
-       if (cmd)
-               reply->rc = (u16) cmd->hdr.return_code;
-       else if (iob->rc)
-               reply->rc = iob->rc;
 
-       if (!keep_reply)
+       if (rc <= 0) {
+               if (cmd)
+                       reply->rc = (u16) cmd->hdr.return_code;
+
+               /* for callbacks with proper errnos: */
+               if (rc < 0)
+                       reply->rc = rc;
                qeth_notify_reply(reply);
+       }
+
        qeth_put_reply(reply);
 
 out:
@@ -1293,7 +1296,6 @@ static int qeth_setup_channel(struct qeth_channel *channel, bool alloc_buffers)
                channel->iob[cnt].state = BUF_STATE_FREE;
                channel->iob[cnt].channel = channel;
                channel->iob[cnt].callback = qeth_send_control_data_cb;
-               channel->iob[cnt].rc = 0;
        }
        if (cnt < QETH_CMD_BUFFER_NO) {
                qeth_clean_channel(channel);
@@ -2343,9 +2345,8 @@ static int qeth_ulp_setup_cb(struct qeth_card *card, struct qeth_reply *reply,
                QETH_DBF_TEXT(SETUP, 2, "olmlimit");
                dev_err(&card->gdev->dev, "A connection could not be "
                        "established because of an OLM limit\n");
-               iob->rc = -EMLINK;
+               return -EMLINK;
        }
-       QETH_DBF_TEXT_(SETUP, 2, "  rc%d", iob->rc);
        return 0;
 }
 
@@ -2900,9 +2901,19 @@ int qeth_send_ipa_cmd(struct qeth_card *card, struct qeth_cmd_buffer *iob,
 }
 EXPORT_SYMBOL_GPL(qeth_send_ipa_cmd);
 
+static int qeth_send_startlan_cb(struct qeth_card *card,
+                                struct qeth_reply *reply, unsigned long data)
+{
+       struct qeth_ipa_cmd *cmd = (struct qeth_ipa_cmd *) data;
+
+       if (cmd->hdr.return_code == IPA_RC_LAN_OFFLINE)
+               return -ENETDOWN;
+
+       return (cmd->hdr.return_code) ? -EIO : 0;
+}
+
 static int qeth_send_startlan(struct qeth_card *card)
 {
-       int rc;
        struct qeth_cmd_buffer *iob;
 
        QETH_DBF_TEXT(SETUP, 2, "strtlan");
@@ -2910,8 +2921,7 @@ static int qeth_send_startlan(struct qeth_card *card)
        iob = qeth_get_ipacmd_buffer(card, IPA_CMD_STARTLAN, 0);
        if (!iob)
                return -ENOMEM;
-       rc = qeth_send_ipa_cmd(card, iob, NULL, NULL);
-       return rc;
+       return qeth_send_ipa_cmd(card, iob, qeth_send_startlan_cb, NULL);
 }
 
 static int qeth_setadpparms_inspect_rc(struct qeth_ipa_cmd *cmd)
@@ -4238,12 +4248,15 @@ static int qeth_setadpparms_change_macaddr_cb(struct qeth_card *card,
 
        QETH_CARD_TEXT(card, 4, "chgmaccb");
        if (qeth_setadpparms_inspect_rc(cmd))
-               return 0;
+               return -EIO;
 
        adp_cmd = &cmd->data.setadapterparms;
+       if (!is_valid_ether_addr(adp_cmd->data.change_addr.addr))
+               return -EADDRNOTAVAIL;
+
        if (IS_LAYER2(card) && IS_OSD(card) && !IS_VM_NIC(card) &&
            !(adp_cmd->hdr.flags & QETH_SETADP_FLAGS_VIRTUAL_MAC))
-               return 0;
+               return -EADDRNOTAVAIL;
 
        ether_addr_copy(card->dev->dev_addr, adp_cmd->data.change_addr.addr);
        return 0;
@@ -4507,13 +4520,13 @@ static int qeth_snmp_command_cb(struct qeth_card *card,
 
        if (cmd->hdr.return_code) {
                QETH_CARD_TEXT_(card, 4, "scer1%x", cmd->hdr.return_code);
-               return 0;
+               return -EIO;
        }
        if (cmd->data.setadapterparms.hdr.return_code) {
                cmd->hdr.return_code =
                        cmd->data.setadapterparms.hdr.return_code;
                QETH_CARD_TEXT_(card, 4, "scer2%x", cmd->hdr.return_code);
-               return 0;
+               return -EIO;
        }
        data_len = *((__u16 *)QETH_IPA_PDU_LEN_PDU1(data));
        if (cmd->data.setadapterparms.hdr.seq_no == 1) {
@@ -4528,9 +4541,8 @@ static int qeth_snmp_command_cb(struct qeth_card *card,
 
        /* check if there is enough room in userspace */
        if ((qinfo->udata_len - qinfo->udata_offset) < data_len) {
-               QETH_CARD_TEXT_(card, 4, "scer3%i", -ENOMEM);
-               cmd->hdr.return_code = IPA_RC_ENOMEM;
-               return 0;
+               QETH_CARD_TEXT_(card, 4, "scer3%i", -ENOSPC);
+               return -ENOSPC;
        }
        QETH_CARD_TEXT_(card, 4, "snore%i",
                       cmd->data.setadapterparms.hdr.used_total);
@@ -4625,16 +4637,14 @@ static int qeth_setadpparms_query_oat_cb(struct qeth_card *card,
 
        QETH_CARD_TEXT(card, 3, "qoatcb");
        if (qeth_setadpparms_inspect_rc(cmd))
-               return 0;
+               return -EIO;
 
        priv = (struct qeth_qoat_priv *)reply->param;
        resdatalen = cmd->data.setadapterparms.hdr.cmdlength;
        resdata = (char *)data + 28;
 
-       if (resdatalen > (priv->buffer_len - priv->response_len)) {
-               cmd->hdr.return_code = IPA_RC_FFFF;
-               return 0;
-       }
+       if (resdatalen > (priv->buffer_len - priv->response_len))
+               return -ENOSPC;
 
        memcpy((priv->buffer + priv->response_len), resdata,
                resdatalen);
@@ -4707,9 +4717,7 @@ static int qeth_query_oat_command(struct qeth_card *card, char __user *udata)
                if (copy_to_user(udata, &oat_data,
                    sizeof(struct qeth_query_oat_data)))
                        rc = -EFAULT;
-       } else
-               if (rc == IPA_RC_FFFF)
-                       rc = -EFAULT;
+       }
 
 out_free:
        vfree(priv.buffer);
@@ -5128,12 +5136,10 @@ retriable:
        rc = qeth_send_startlan(card);
        if (rc) {
                QETH_DBF_TEXT_(SETUP, 2, "6err%d", rc);
-               if (rc == IPA_RC_LAN_OFFLINE) {
-                       dev_warn(&card->gdev->dev,
-                               "The LAN is offline\n");
+               if (rc == -ENETDOWN) {
+                       dev_warn(&card->gdev->dev, "The LAN is offline\n");
                        *carrier_ok = false;
                } else {
-                       rc = -ENODEV;
                        goto out;
                }
        } else {

diff --git a/drivers/s390/net/qeth_core_mpc.c b/drivers/s390/net/qeth_core_mpc.c
index 7ff221ae0a2e1a279ae64092a81bf7a11d9852fc..e3f4866c158e4873c6531e93258c4463297ba2a9 100644 (file)
--- a/drivers/s390/net/qeth_core_mpc.c
+++ b/drivers/s390/net/qeth_core_mpc.c
@@ -201,12 +201,10 @@ static const struct ipa_rc_msg qeth_ipa_rc_msg[] = {
        {IPA_RC_LAN_OFFLINE,            "STRTLAN_LAN_DISABLED - LAN offline"},
        {IPA_RC_VEPA_TO_VEB_TRANSITION, "Adj. switch disabled port mode RR"},
        {IPA_RC_INVALID_IP_VERSION2,    "Invalid IP version"},
-       {IPA_RC_ENOMEM,                 "Memory problem"},
+       /* default for qeth_get_ipa_msg(): */
        {IPA_RC_FFFF,                   "Unknown Error"}
 };
 
-
-
 const char *qeth_get_ipa_msg(enum qeth_ipa_return_codes rc)
 {
        int x;

diff --git a/drivers/s390/net/qeth_core_mpc.h b/drivers/s390/net/qeth_core_mpc.h
index 7919a0c8109ae5724947dadf33f9bbd0cc9e7ad0..4b1690380ebe5b7110cd4ee606cf880eb67bafe8 100644 (file)
--- a/drivers/s390/net/qeth_core_mpc.h
+++ b/drivers/s390/net/qeth_core_mpc.h
@@ -229,7 +229,6 @@ enum qeth_ipa_return_codes {
        IPA_RC_LAN_OFFLINE              = 0xe080,
        IPA_RC_VEPA_TO_VEB_TRANSITION   = 0xe090,
        IPA_RC_INVALID_IP_VERSION2      = 0xf001,
-       IPA_RC_ENOMEM                   = 0xfffe,
        IPA_RC_FFFF                     = 0xffff
 };
 /* for VNIC Characteristics */

diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index 453b3f7f272c49640162e6374b4b0454534f1b5d..6d9eb54ea3b02447ca0d7ff8fc753579b76a5409 100644 (file)
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -393,7 +393,7 @@ static int qeth_l2_request_initial_mac(struct qeth_card *card)
 
        if (!IS_OSN(card)) {
                rc = qeth_setadpparms_change_macaddr(card);
-               if (!rc && is_valid_ether_addr(card->dev->dev_addr))
+               if (!rc)
                        goto out;
                QETH_DBF_MESSAGE(2, "READ_MAC Assist failed on device %x: %#x\n",
                                 CARD_DEVID(card), rc);

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index f0b790810ebc8bcd6d68c48f96b43e9f2c9c3f2f..852bfd5cc3e9117ff347b23316ed06bd17d150ad 100644 (file)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -253,8 +253,7 @@ static int qeth_l3_add_ip(struct qeth_card *card, struct qeth_ipaddr *tmp_addr)
                } else
                        rc = qeth_l3_register_addr_entry(card, addr);
 
-               if (!rc || (rc == IPA_RC_DUPLICATE_IP_ADDRESS) ||
-                               (rc == IPA_RC_LAN_OFFLINE)) {
+               if (!rc || rc == -EADDRINUSE || rc == -ENETDOWN) {
                        addr->disp_flag = QETH_DISP_ADDR_DO_NOTHING;
                        if (addr->ref_counter < 1) {
                                qeth_l3_deregister_addr_entry(card, addr);
@@ -338,10 +337,28 @@ static void qeth_l3_recover_ip(struct qeth_card *card)
 
 }
 
+static int qeth_l3_setdelip_cb(struct qeth_card *card, struct qeth_reply *reply,
+                              unsigned long data)
+{
+       struct qeth_ipa_cmd *cmd = (struct qeth_ipa_cmd *) data;
+
+       switch (cmd->hdr.return_code) {
+       case IPA_RC_SUCCESS:
+               return 0;
+       case IPA_RC_DUPLICATE_IP_ADDRESS:
+               return -EADDRINUSE;
+       case IPA_RC_MC_ADDR_NOT_FOUND:
+               return -ENOENT;
+       case IPA_RC_LAN_OFFLINE:
+               return -ENETDOWN;
+       default:
+               return -EIO;
+       }
+}
+
 static int qeth_l3_send_setdelmc(struct qeth_card *card,
                        struct qeth_ipaddr *addr, int ipacmd)
 {
-       int rc;
        struct qeth_cmd_buffer *iob;
        struct qeth_ipa_cmd *cmd;
 
@@ -358,9 +375,7 @@ static int qeth_l3_send_setdelmc(struct qeth_card *card,
        else
                memcpy(&cmd->data.setdelipm.ip4, &addr->u.a4.addr, 4);
 
-       rc = qeth_send_ipa_cmd(card, iob, NULL, NULL);
-
-       return rc;
+       return qeth_send_ipa_cmd(card, iob, qeth_l3_setdelip_cb, NULL);
 }
 
 static void qeth_l3_fill_netmask(u8 *netmask, unsigned int len)
@@ -422,7 +437,7 @@ static int qeth_l3_send_setdelip(struct qeth_card *card,
                cmd->data.setdelip4.flags = flags;
        }
 
-       return qeth_send_ipa_cmd(card, iob, NULL, NULL);
+       return qeth_send_ipa_cmd(card, iob, qeth_l3_setdelip_cb, NULL);
 }
 
 static int qeth_l3_send_setrouting(struct qeth_card *card,
@@ -1481,14 +1496,14 @@ static void qeth_l3_set_rx_mode(struct net_device *dev)
                        switch (addr->disp_flag) {
                        case QETH_DISP_ADDR_DELETE:
                                rc = qeth_l3_deregister_addr_entry(card, addr);
-                               if (!rc || rc == IPA_RC_MC_ADDR_NOT_FOUND) {
+                               if (!rc || rc == -ENOENT) {
                                        hash_del(&addr->hnode);
                                        kfree(addr);
                                }
                                break;
                        case QETH_DISP_ADDR_ADD:
                                rc = qeth_l3_register_addr_entry(card, addr);
-                               if (rc && rc != IPA_RC_LAN_OFFLINE) {
+                               if (rc && rc != -ENETDOWN) {
                                        hash_del(&addr->hnode);
                                        kfree(addr);
                                        break;
@@ -1599,7 +1614,6 @@ static int qeth_l3_arp_query_cb(struct qeth_card *card,
        struct qeth_ipa_cmd *cmd;
        struct qeth_arp_query_data *qdata;
        struct qeth_arp_query_info *qinfo;
-       int i;
        int e;
        int entrybytes_done;
        int stripped_bytes;
@@ -1613,13 +1627,13 @@ static int qeth_l3_arp_query_cb(struct qeth_card *card,
        if (cmd->hdr.return_code) {
                QETH_CARD_TEXT(card, 4, "arpcberr");
                QETH_CARD_TEXT_(card, 4, "%i", cmd->hdr.return_code);
-               return 0;
+               return qeth_l3_arp_makerc(cmd->hdr.return_code);
        }
        if (cmd->data.setassparms.hdr.return_code) {
                cmd->hdr.return_code = cmd->data.setassparms.hdr.return_code;
                QETH_CARD_TEXT(card, 4, "setaperr");
                QETH_CARD_TEXT_(card, 4, "%i", cmd->hdr.return_code);
-               return 0;
+               return qeth_l3_arp_makerc(cmd->hdr.return_code);
        }
        qdata = &cmd->data.setassparms.data.query_arp;
        QETH_CARD_TEXT_(card, 4, "anoen%i", qdata->no_entries);
@@ -1646,9 +1660,9 @@ static int qeth_l3_arp_query_cb(struct qeth_card *card,
                        break;
 
                if ((qinfo->udata_len - qinfo->udata_offset) < esize) {
-                       QETH_CARD_TEXT_(card, 4, "qaer3%i", -ENOMEM);
-                       cmd->hdr.return_code = IPA_RC_ENOMEM;
-                       goto out_error;
+                       QETH_CARD_TEXT_(card, 4, "qaer3%i", -ENOSPC);
+                       memset(qinfo->udata, 0, 4);
+                       return -ENOSPC;
                }
 
                memcpy(qinfo->udata + qinfo->udata_offset,
@@ -1671,10 +1685,6 @@ static int qeth_l3_arp_query_cb(struct qeth_card *card,
        memcpy(qinfo->udata + QETH_QARP_MASK_OFFSET, &qdata->reply_bits, 2);
        QETH_CARD_TEXT_(card, 4, "rc%i", 0);
        return 0;
-out_error:
-       i = 0;
-       memcpy(qinfo->udata, &i, 4);
-       return 0;
 }
 
 static int qeth_l3_query_arp_cache_info(struct qeth_card *card,
@@ -1700,7 +1710,7 @@ static int qeth_l3_query_arp_cache_info(struct qeth_card *card,
        if (rc)
                QETH_DBF_MESSAGE(2, "Error while querying ARP cache on device %x: %#x\n",
                                 CARD_DEVID(card), rc);
-       return qeth_l3_arp_makerc(rc);
+       return rc;
 }
 
 static int qeth_l3_arp_query(struct qeth_card *card, char __user *udata)