[RFC net-next 14/17] net/dibs: Move vlan support to dibs_dev_ops

[Alexandra Winter <wintera@linux.ibm.com>]

It can be debated how much benefit definition of vlan ids for dibs devices
brings, as the dmbs are accessible only by a single peer anyhow. But ism
provides vlan support and smcd exploits it, so move it to dibs layer as an
optional feature.

smcd_loopback simply ignores all vlan settings, do the same in
dibs_loopback.

SMC-D and ISM have a method to use the invalid VLAN ID 1FFF
(ISM_RESERVED_VLANID), to indicate that both communication peers support
routable SMC-Dv2. Tolerate it in dibs, but move it to SMC only.

Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
---
 drivers/s390/net/ism_drv.c | 47 +++++---------------------------------
 include/linux/dibs.h       | 19 +++++++++++++++
 include/net/smc.h          |  5 ----
 net/smc/smc_ism.c          | 14 ++++++++----
 net/smc/smc_loopback.c     |  5 ----
 5 files changed, 34 insertions(+), 56 deletions(-)

diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index 2dbf4ebb6bff..636594b2fab2 100644
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -36,7 +36,6 @@ static struct ism_client *clients[MAX_CLIENTS];	/* use an array rather than */
 						/* a list for fast mapping  */
 static u8 max_client;
 static DEFINE_MUTEX(clients_lock);
-static bool ism_v2_capable;
 struct ism_dev_list {
 	struct list_head list;
 	struct mutex mutex; /* protects ism device list */
@@ -409,8 +408,9 @@ int ism_unregister_dmb(struct ism_dev *ism, struct ism_dmb *dmb)
 }
 EXPORT_SYMBOL_GPL(ism_unregister_dmb);
 
-static int ism_add_vlan_id(struct ism_dev *ism, u64 vlan_id)
+static int ism_add_vlan_id(struct dibs_dev *dibs, u64 vlan_id)
 {
+	struct ism_dev *ism = dibs->drv_priv;
 	union ism_set_vlan_id cmd;
 
 	memset(&cmd, 0, sizeof(cmd));
@@ -422,8 +422,9 @@ static int ism_add_vlan_id(struct ism_dev *ism, u64 vlan_id)
 	return ism_cmd(ism, &cmd);
 }
 
-static int ism_del_vlan_id(struct ism_dev *ism, u64 vlan_id)
+static int ism_del_vlan_id(struct dibs_dev *dibs, u64 vlan_id)
 {
+	struct ism_dev *ism = dibs->drv_priv;
 	union ism_set_vlan_id cmd;
 
 	memset(&cmd, 0, sizeof(cmd));
@@ -536,6 +537,8 @@ static irqreturn_t ism_handle_irq(int irq, void *data)
 
 static const struct dibs_dev_ops ism_ops = {
 	.get_fabric_id = ism_get_chid,
+	.add_vlan_id = ism_add_vlan_id,
+	.del_vlan_id = ism_del_vlan_id,
 };
 
 static int ism_dev_init(struct ism_dev *ism)
@@ -565,12 +568,6 @@ static int ism_dev_init(struct ism_dev *ism)
 	if (ret)
 		goto unreg_sba;
 
-	if (!ism_add_vlan_id(ism, ISM_RESERVED_VLANID))
-		/* hardware is V2 capable */
-		ism_v2_capable = true;
-	else
-		ism_v2_capable = false;
-
 	mutex_lock(&ism_dev_list.mutex);
 	mutex_lock(&clients_lock);
 	for (i = 0; i < max_client; ++i) {
@@ -611,8 +608,6 @@ static void ism_dev_exit(struct ism_dev *ism)
 
 	mutex_lock(&ism_dev_list.mutex);
 
-	if (ism_v2_capable)
-		ism_del_vlan_id(ism, ISM_RESERVED_VLANID);
 	unregister_ieq(ism);
 	unregister_sba(ism);
 	free_irq(pci_irq_vector(pdev, 0), ism);
@@ -791,26 +786,6 @@ static int smcd_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
 	return ism_unregister_dmb(smcd->priv, (struct ism_dmb *)dmb);
 }
 
-static int smcd_add_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
-{
-	return ism_add_vlan_id(smcd->priv, vlan_id);
-}
-
-static int smcd_del_vlan_id(struct smcd_dev *smcd, u64 vlan_id)
-{
-	return ism_del_vlan_id(smcd->priv, vlan_id);
-}
-
-static int smcd_set_vlan_required(struct smcd_dev *smcd)
-{
-	return ism_cmd_simple(smcd->priv, ISM_SET_VLAN);
-}
-
-static int smcd_reset_vlan_required(struct smcd_dev *smcd)
-{
-	return ism_cmd_simple(smcd->priv, ISM_RESET_VLAN);
-}
-
 static int ism_signal_ieq(struct ism_dev *ism, u64 rgid, u32 trigger_irq,
 			  u32 event_code, u64 info)
 {
@@ -842,22 +817,12 @@ static int smcd_move(struct smcd_dev *smcd, u64 dmb_tok, unsigned int idx,
 	return ism_move(smcd->priv, dmb_tok, idx, sf, offset, data, size);
 }
 
-static int smcd_supports_v2(void)
-{
-	return ism_v2_capable;
-}
-
 static const struct smcd_ops ism_smcd_ops = {
 	.query_remote_gid = smcd_query_rgid,
 	.register_dmb = smcd_register_dmb,
 	.unregister_dmb = smcd_unregister_dmb,
-	.add_vlan_id = smcd_add_vlan_id,
-	.del_vlan_id = smcd_del_vlan_id,
-	.set_vlan_required = smcd_set_vlan_required,
-	.reset_vlan_required = smcd_reset_vlan_required,
 	.signal_event = smcd_signal_ieq,
 	.move_data = smcd_move,
-	.supports_v2 = smcd_supports_v2,
 };
 
 const struct smcd_ops *ism_get_smcd_ops(void)
diff --git a/include/linux/dibs.h b/include/linux/dibs.h
index 058dfc14aa5c..10be10ae4660 100644
--- a/include/linux/dibs.h
+++ b/include/linux/dibs.h
@@ -133,6 +133,25 @@ struct dibs_dev_ops {
 	 * Return: 2 byte dibs fabric id
 	 */
 	u16 (*get_fabric_id)(struct dibs_dev *dev);
+	/**
+	 * add_vlan_id() - add dibs device to vlan (optional, deprecated)
+	 * @dev: dibs device
+	 * @vlan_id: vlan id
+	 *
+	 * In order to write into a vlan-tagged dmb, the remote device needs
+	 * to belong to the this vlan. A device can belong to more than 1 vlan.
+	 * Any device can access an untagged dmb.
+	 * Deprecated, only supported for backwards compatibility.
+	 * Return: zero on success
+	 */
+	int (*add_vlan_id)(struct dibs_dev *dev, u64 vlan_id);
+	/**
+	 * del_vlan_id() - remove dibs device from vlan (optional, deprecated)
+	 * @dev: dibs device
+	 * @vlan_id: vlan id
+	 * Return: zero on success
+	 */
+	int (*del_vlan_id)(struct dibs_dev *dev, u64 vlan_id);
 };
 
 struct dibs_dev {
diff --git a/include/net/smc.h b/include/net/smc.h
index 9cb8385bbc6e..51b4aefc106a 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -61,13 +61,8 @@ struct smcd_ops {
 	int (*move_data)(struct smcd_dev *dev, u64 dmb_tok, unsigned int idx,
 			 bool sf, unsigned int offset, void *data,
 			 unsigned int size);
-	int (*supports_v2)(void);
 
 	/* optional operations */
-	int (*add_vlan_id)(struct smcd_dev *dev, u64 vlan_id);
-	int (*del_vlan_id)(struct smcd_dev *dev, u64 vlan_id);
-	int (*set_vlan_required)(struct smcd_dev *dev);
-	int (*reset_vlan_required)(struct smcd_dev *dev);
 	int (*signal_event)(struct smcd_dev *dev, struct smcd_gid *rgid,
 			    u32 trigger_irq, u32 event_code, u64 info);
 	int (*support_dmb_nocopy)(struct smcd_dev *dev);
diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index dd46d8000381..ce9d2195e14a 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -140,7 +140,7 @@ int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
 
 	if (!vlanid)			/* No valid vlan id */
 		return -EINVAL;
-	if (!smcd->ops->add_vlan_id)
+	if (!smcd->dibs->ops->add_vlan_id)
 		return -EOPNOTSUPP;
 
 	/* create new vlan entry, in case we need it */
@@ -163,7 +163,7 @@ int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
 	/* no existing entry found.
 	 * add new entry to device; might fail, e.g., if HW limit reached
 	 */
-	if (smcd->ops->add_vlan_id(smcd, vlanid)) {
+	if (smcd->dibs->ops->add_vlan_id(smcd->dibs, vlanid)) {
 		kfree(new_vlan);
 		rc = -EIO;
 		goto out;
@@ -187,7 +187,7 @@ int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
 
 	if (!vlanid)			/* No valid vlan id */
 		return -EINVAL;
-	if (!smcd->ops->del_vlan_id)
+	if (!smcd->dibs->ops->del_vlan_id)
 		return -EOPNOTSUPP;
 
 	spin_lock_irqsave(&smcd->lock, flags);
@@ -205,7 +205,7 @@ int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
 	}
 
 	/* Found and the last reference just gone */
-	if (smcd->ops->del_vlan_id(smcd, vlanid))
+	if (smcd->dibs->ops->del_vlan_id(smcd->dibs, vlanid))
 		rc = -EIO;
 	list_del(&vlan->list);
 	kfree(vlan);
@@ -536,8 +536,12 @@ static void smcd_register_dev(struct dibs_dev *dibs)
 
 	smcd->client = &smc_ism_client;
 
-	if (smcd->ops->supports_v2())
+	if (smc_ism_is_loopback(dibs) ||
+	    (dibs->ops->add_vlan_id &&
+	     !dibs->ops->add_vlan_id(dibs, ISM_RESERVED_VLANID))) {
 		smc_ism_set_v2_capable();
+	}
+
 	mutex_lock(&smcd_dev_list.mutex);
 	/* sort list:
 	 * - devices without pnetid before devices with pnetid;
diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c
index 454d9d6a6e8f..982a19430313 100644
--- a/net/smc/smc_loopback.c
+++ b/net/smc/smc_loopback.c
@@ -20,7 +20,6 @@
 #include "smc_ism.h"
 #include "smc_loopback.h"
 
-#define SMC_LO_V2_CAPABLE	0x1 /* loopback-ism acts as ISMv2 */
 #define SMC_LO_SUPPORT_NOCOPY	0x1
 #define SMC_DMA_ADDR_INVALID	(~(dma_addr_t)0)
 
@@ -242,10 +241,6 @@ static const struct smcd_ops lo_ops = {
 	.support_dmb_nocopy = smc_lo_support_dmb_nocopy,
 	.attach_dmb = smc_lo_attach_dmb,
 	.detach_dmb = smc_lo_detach_dmb,
-	.add_vlan_id		= NULL,
-	.del_vlan_id		= NULL,
-	.set_vlan_required	= NULL,
-	.reset_vlan_required	= NULL,
 	.signal_event		= NULL,
 	.move_data = smc_lo_move_data,
 };
-- 
2.48.1