dibs: Create class dibs

Create '/sys/class/dibs' to represent multiple kinds of dibs devices in
sysfs. Show s390/ism devices as well as dibs_loopback devices.

Show attribute fabric_id using dibs_ops.get_fabric_id(). This can help
users understand which dibs devices are connected to the same fabric in
different systems and which dibs devices are loopback devices
(fabric_id 0xffff)

Instead of using the same name as the pci device, give the ism devices
their own readable names based on uid or fid from the HW definition.

smc_loopback was never visible in sysfs. dibs_loopback is now represented
as a virtual device.

For the SMC feature "software defined pnet-id" either the ib device name or
the PCI-ID (actually the parent device name) can be used for SMC-R entries.
Mimic this behaviour for SMC-D, and check the parent device name as well.
So device name or PCI-ID can be used for ism and device name can be used
for dibs-loopback. Note that this:
IB_DEVICE_NAME_MAX - 1 == smc_pnet_policy.[SMC_PNETID_IBNAME].len
is the length of smcd_name. Future SW-pnetid cleanup patches to could use a
meaningful define, but that would touch too much unrelated code here.

Examples:
---------
ism before:
> ls /sys/bus/pci/devices/0000:00:00.0/0000:00:00.0
uevent

ism now:
> ls /sys/bus/pci/devices/0000:00:00.0/dibs/ism30
device -> ../../../0000:00:00.0/
fabric_id
subsystem -> ../../../../../class/dibs/
uevent

dibs loopback:
> ls /sys/devices/virtual/dibs/lo/
fabric_id
subsystem -> ../../../../class/dibs/
uevent

dibs class:
> ls -l /sys/class/dibs/
ism30 -> ../../devices/pci0000:00/0000:00:00.0/dibs/ism30/
lo -> ../../devices/virtual/dibs/lo/

For comparison:
> ls -l /sys/class/net/
enc8410 -> ../../devices/qeth/0.0.8410/net/enc8410/
ens1693 -> ../../devices/pci0001:00/0001:00:00.0/net/ens1693/
lo -> ../../devices/virtual/net/lo/

Signed-off-by: Julian Ruess <julianr@linux.ibm.com>
Co-developed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-10-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/dibs/dibs_main.c b/drivers/dibs/dibs_main.c
index 610b6c452211d6e3ace50ffe347abf57d0f7b628..b3f21805aa59a9f6f829a0f70a433b8466c5d446 100644 (file)
--- a/drivers/dibs/dibs_main.c
+++ b/drivers/dibs/dibs_main.c
@@ -20,6 +20,8 @@
 MODULE_DESCRIPTION("Direct Internal Buffer Sharing class");
 MODULE_LICENSE("GPL");
 
+static struct class *dibs_class;
+
 /* use an array rather a list for fast mapping: */
 static struct dibs_client *clients[MAX_DIBS_CLIENTS];
 static u8 max_client;
@@ -105,12 +107,35 @@ struct dibs_dev *dibs_dev_alloc(void)
        if (!dibs)
                return dibs;
        dibs->dev.release = dibs_dev_release;
+       dibs->dev.class = dibs_class;
        device_initialize(&dibs->dev);
 
        return dibs;
 }
 EXPORT_SYMBOL_GPL(dibs_dev_alloc);
 
+static ssize_t fabric_id_show(struct device *dev, struct device_attribute *attr,
+                             char *buf)
+{
+       struct dibs_dev *dibs;
+       u16 fabric_id;
+
+       dibs = container_of(dev, struct dibs_dev, dev);
+       fabric_id = dibs->ops->get_fabric_id(dibs);
+
+       return sysfs_emit(buf, "0x%04x\n", fabric_id);
+}
+static DEVICE_ATTR_RO(fabric_id);
+
+static struct attribute *dibs_dev_attrs[] = {
+       &dev_attr_fabric_id.attr,
+       NULL,
+};
+
+static const struct attribute_group dibs_dev_attr_group = {
+       .attrs = dibs_dev_attrs,
+};
+
 int dibs_dev_add(struct dibs_dev *dibs)
 {
        int i, ret;
@@ -119,6 +144,11 @@ int dibs_dev_add(struct dibs_dev *dibs)
        if (ret)
                return ret;
 
+       ret = sysfs_create_group(&dibs->dev.kobj, &dibs_dev_attr_group);
+       if (ret) {
+               dev_err(&dibs->dev, "sysfs_create_group failed for dibs_dev\n");
+               goto err_device_del;
+       }
        mutex_lock(&dibs_dev_list.mutex);
        mutex_lock(&clients_lock);
        for (i = 0; i < max_client; ++i) {
@@ -130,6 +160,11 @@ int dibs_dev_add(struct dibs_dev *dibs)
        mutex_unlock(&dibs_dev_list.mutex);
 
        return 0;
+
+err_device_del:
+       device_del(&dibs->dev);
+       return ret;
+
 }
 EXPORT_SYMBOL_GPL(dibs_dev_add);
 
@@ -158,6 +193,10 @@ static int __init dibs_init(void)
        memset(clients, 0, sizeof(clients));
        max_client = 0;
 
+       dibs_class = class_create("dibs");
+       if (IS_ERR(&dibs_class))
+               return PTR_ERR(&dibs_class);
+
        rc = dibs_loopback_init();
        if (rc)
                pr_err("%s fails with %d\n", __func__, rc);
@@ -168,6 +207,7 @@ static int __init dibs_init(void)
 static void __exit dibs_exit(void)
 {
        dibs_loopback_exit();
+       class_destroy(dibs_class);
 }
 
 module_init(dibs_init);

diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c
index 4096ea9faa7ea41e18db290d9d22f0d6ba6d2e8f..ab1d61eb3e3bf28e1ab7b09a7bf031a07a44b973 100644 (file)
--- a/drivers/s390/net/ism_drv.c
+++ b/drivers/s390/net/ism_drv.c
@@ -629,6 +629,7 @@ static void ism_dev_exit(struct ism_dev *ism)
 static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
        struct dibs_dev *dibs;
+       struct zpci_dev *zdev;
        struct ism_dev *ism;
        int ret;
 
@@ -672,7 +673,9 @@ static int ism_probe(struct pci_dev *pdev, const struct pci_device_id *id)
                goto err_dibs;
 
        dibs->dev.parent = &pdev->dev;
-       dev_set_name(&dibs->dev, "%s", dev_name(&pdev->dev));
+
+       zdev = to_zpci(pdev);
+       dev_set_name(&dibs->dev, "ism%x", zdev->uid ? zdev->uid : zdev->fid);
 
        ret = dibs_dev_add(dibs);
        if (ret)

diff --git a/net/smc/smc_pnet.c b/net/smc/smc_pnet.c
index d0df7f2b03aadeba7ba3be62513a6986bb7577e7..a3a1e1fde8eb64a48c9bfcb7349e0cc003980f00 100644 (file)
--- a/net/smc/smc_pnet.c
+++ b/net/smc/smc_pnet.c
@@ -332,8 +332,11 @@ static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
 
        mutex_lock(&smcd_dev_list.mutex);
        list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
-               if (!strncmp(dev_name(&smcd_dev->dibs->dev),
-                            smcd_name, IB_DEVICE_NAME_MAX - 1))
+               if (!strncmp(dev_name(&smcd_dev->dibs->dev), smcd_name,
+                            IB_DEVICE_NAME_MAX - 1) ||
+                   (smcd_dev->dibs->dev.parent &&
+                    !strncmp(dev_name(smcd_dev->dibs->dev.parent), smcd_name,
+                             IB_DEVICE_NAME_MAX - 1)))
                        goto out;
        }
        smcd_dev = NULL;
@@ -1190,7 +1193,6 @@ int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
  */
 int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
 {
-       const char *ib_name = dev_name(&smcddev->dibs->dev);
        struct smc_pnettable *pnettable;
        struct smc_pnetentry *tmp_pe;
        struct smc_net *sn;
@@ -1203,7 +1205,13 @@ int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
        mutex_lock(&pnettable->lock);
        list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
                if (tmp_pe->type == SMC_PNET_IB &&
-                   !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
+                   (!strncmp(tmp_pe->ib_name,
+                              dev_name(&smcddev->dibs->dev),
+                              sizeof(tmp_pe->ib_name)) ||
+                    (smcddev->dibs->dev.parent &&
+                     !strncmp(tmp_pe->ib_name,
+                              dev_name(smcddev->dibs->dev.parent),
+                              sizeof(tmp_pe->ib_name))))) {
                        smc_pnet_apply_smcd(smcddev, tmp_pe->pnet_name);
                        rc = 0;
                        break;