vio: make remove callback return void

The driver core ignores the return value of struct bus_type::remove()
because there is only little that can be done. To simplify the quest to
make this function return void, let struct vio_driver::remove() return
void, too. All users already unconditionally return 0, this commit makes
it obvious that returning an error code is a bad idea.

Note there are two nominally different implementations for a vio bus:
one in arch/sparc/kernel/vio.c and the other in
arch/powerpc/platforms/pseries/vio.c. This patch only adapts the powerpc
one.

Before this patch for a device that was bound to a driver without a
remove callback vio_cmo_bus_remove(viodev) wasn't called. As the device
core still considers the device unbound after vio_bus_remove() returns
calling this unconditionally is the consistent behaviour which is
implemented here.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Reviewed-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Acked-by: Lijun Pan <ljp@linux.ibm.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[mpe: Drop unneeded hvcs_remove() forward declaration, squash in
 change from sfr to drop ibmvnic_remove() forward declaration]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210225221834.160083-1-uwe@kleine-koenig.org

diff --git a/arch/powerpc/include/asm/vio.h b/arch/powerpc/include/asm/vio.h
index 0cf5274..721c0d6 100644 (file)
--- a/arch/powerpc/include/asm/vio.h
+++ b/arch/powerpc/include/asm/vio.h
@@ -113,7 +113,7 @@ struct vio_driver {
        const char *name;
        const struct vio_device_id *id_table;
        int (*probe)(struct vio_dev *dev, const struct vio_device_id *id);
-       int (*remove)(struct vio_dev *dev);
+       void (*remove)(struct vio_dev *dev);
        /* A driver must have a get_desired_dma() function to
         * be loaded in a CMO environment if it uses DMA.
         */

diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c
index b2797cf..9cb4fc8 100644 (file)
--- a/arch/powerpc/platforms/pseries/vio.c
+++ b/arch/powerpc/platforms/pseries/vio.c
@@ -1261,7 +1261,6 @@ static int vio_bus_remove(struct device *dev)
        struct vio_dev *viodev = to_vio_dev(dev);
        struct vio_driver *viodrv = to_vio_driver(dev->driver);
        struct device *devptr;
-       int ret = 1;
 
        /*
         * Hold a reference to the device after the remove function is called
@@ -1270,13 +1269,13 @@ static int vio_bus_remove(struct device *dev)
        devptr = get_device(dev);
 
        if (viodrv->remove)
-               ret = viodrv->remove(viodev);
+               viodrv->remove(viodev);
 
-       if (!ret && firmware_has_feature(FW_FEATURE_CMO))
+       if (firmware_has_feature(FW_FEATURE_CMO))
                vio_cmo_bus_remove(viodev);
 
        put_device(devptr);
-       return ret;
+       return 0;
 }
 
 /**

diff --git a/drivers/char/hw_random/pseries-rng.c b/drivers/char/hw_random/pseries-rng.c
index 8038a8a..f4949b6 100644 (file)
--- a/drivers/char/hw_random/pseries-rng.c
+++ b/drivers/char/hw_random/pseries-rng.c
@@ -54,10 +54,9 @@ static int pseries_rng_probe(struct vio_dev *dev,
        return hwrng_register(&pseries_rng);
 }
 
-static int pseries_rng_remove(struct vio_dev *dev)
+static void pseries_rng_remove(struct vio_dev *dev)
 {
        hwrng_unregister(&pseries_rng);
-       return 0;
 }
 
 static const struct vio_device_id pseries_rng_driver_ids[] = {

diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c
index 994385b..9036047 100644 (file)
--- a/drivers/char/tpm/tpm_ibmvtpm.c
+++ b/drivers/char/tpm/tpm_ibmvtpm.c
@@ -343,7 +343,7 @@ static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
  *
  * Return: Always 0.
  */
-static int tpm_ibmvtpm_remove(struct vio_dev *vdev)
+static void tpm_ibmvtpm_remove(struct vio_dev *vdev)
 {
        struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
        struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
@@ -372,8 +372,6 @@ static int tpm_ibmvtpm_remove(struct vio_dev *vdev)
        kfree(ibmvtpm);
        /* For tpm_ibmvtpm_get_desired_dma */
        dev_set_drvdata(&vdev->dev, NULL);
-
-       return 0;
 }
 
 /**

diff --git a/drivers/crypto/nx/nx-842-pseries.c b/drivers/crypto/nx/nx-842-pseries.c
index 2de5e36..cc8dd30 100644 (file)
--- a/drivers/crypto/nx/nx-842-pseries.c
+++ b/drivers/crypto/nx/nx-842-pseries.c
@@ -1042,7 +1042,7 @@ error:
        return ret;
 }
 
-static int nx842_remove(struct vio_dev *viodev)
+static void nx842_remove(struct vio_dev *viodev)
 {
        struct nx842_devdata *old_devdata;
        unsigned long flags;
@@ -1063,8 +1063,6 @@ static int nx842_remove(struct vio_dev *viodev)
        if (old_devdata)
                kfree(old_devdata->counters);
        kfree(old_devdata);
-
-       return 0;
 }
 
 static const struct vio_device_id nx842_vio_driver_ids[] = {

diff --git a/drivers/crypto/nx/nx.c b/drivers/crypto/nx/nx.c
index 0d2dc5b..1d0e8a1 100644 (file)
--- a/drivers/crypto/nx/nx.c
+++ b/drivers/crypto/nx/nx.c
@@ -783,7 +783,7 @@ static int nx_probe(struct vio_dev *viodev, const struct vio_device_id *id)
        return nx_register_algs();
 }
 
-static int nx_remove(struct vio_dev *viodev)
+static void nx_remove(struct vio_dev *viodev)
 {
        dev_dbg(&viodev->dev, "entering nx_remove for UA 0x%x\n",
                viodev->unit_address);
@@ -811,8 +811,6 @@ static int nx_remove(struct vio_dev *viodev)
                nx_unregister_skcipher(&nx_ecb_aes_alg, NX_FC_AES,
                                       NX_MODE_AES_ECB);
        }
-
-       return 0;
 }
 
 

diff --git a/drivers/misc/ibmvmc.c b/drivers/misc/ibmvmc.c
index 2d778d0..c0fe329 100644 (file)
--- a/drivers/misc/ibmvmc.c
+++ b/drivers/misc/ibmvmc.c
@@ -2288,15 +2288,13 @@ crq_failed:
        return -EPERM;
 }
 
-static int ibmvmc_remove(struct vio_dev *vdev)
+static void ibmvmc_remove(struct vio_dev *vdev)
 {
        struct crq_server_adapter *adapter = dev_get_drvdata(&vdev->dev);
 
        dev_info(adapter->dev, "Entering remove for UA 0x%x\n",
                 vdev->unit_address);
        ibmvmc_release_crq_queue(adapter);
-
-       return 0;
 }
 
 static struct vio_device_id ibmvmc_device_table[] = {

diff --git a/drivers/net/ethernet/ibm/ibmveth.c b/drivers/net/ethernet/ibm/ibmveth.c
index c3ec9ce..7fea9ae 100644 (file)
--- a/drivers/net/ethernet/ibm/ibmveth.c
+++ b/drivers/net/ethernet/ibm/ibmveth.c
@@ -1758,7 +1758,7 @@ static int ibmveth_probe(struct vio_dev *dev, const struct vio_device_id *id)
        return 0;
 }
 
-static int ibmveth_remove(struct vio_dev *dev)
+static void ibmveth_remove(struct vio_dev *dev)
 {
        struct net_device *netdev = dev_get_drvdata(&dev->dev);
        struct ibmveth_adapter *adapter = netdev_priv(netdev);
@@ -1771,8 +1771,6 @@ static int ibmveth_remove(struct vio_dev *dev)
 
        free_netdev(netdev);
        dev_set_drvdata(&dev->dev, NULL);
-
-       return 0;
 }
 
 static struct attribute veth_active_attr;

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 118a4bd..fe3201b 100644 (file)
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -78,7 +78,6 @@ MODULE_LICENSE("GPL");
 MODULE_VERSION(IBMVNIC_DRIVER_VERSION);
 
 static int ibmvnic_version = IBMVNIC_INITIAL_VERSION;
-static int ibmvnic_remove(struct vio_dev *);
 static void release_sub_crqs(struct ibmvnic_adapter *, bool);
 static int ibmvnic_reset_crq(struct ibmvnic_adapter *);
 static int ibmvnic_send_crq_init(struct ibmvnic_adapter *);
@@ -5396,7 +5395,7 @@ ibmvnic_init_fail:
        return rc;
 }
 
-static int ibmvnic_remove(struct vio_dev *dev)
+static void ibmvnic_remove(struct vio_dev *dev)
 {
        struct net_device *netdev = dev_get_drvdata(&dev->dev);
        struct ibmvnic_adapter *adapter = netdev_priv(netdev);
@@ -5437,8 +5436,6 @@ static int ibmvnic_remove(struct vio_dev *dev)
        device_remove_file(&dev->dev, &dev_attr_failover);
        free_netdev(netdev);
        dev_set_drvdata(&dev->dev, NULL);
-
-       return 0;
 }
 
 static ssize_t failover_store(struct device *dev, struct device_attribute *attr,

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 755313b..e663085 100644 (file)
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -6038,7 +6038,7 @@ out:
  * Return value:
  *     0
  **/
-static int ibmvfc_remove(struct vio_dev *vdev)
+static void ibmvfc_remove(struct vio_dev *vdev)
 {
        struct ibmvfc_host *vhost = dev_get_drvdata(&vdev->dev);
        LIST_HEAD(purge);
@@ -6070,7 +6070,6 @@ static int ibmvfc_remove(struct vio_dev *vdev)
        spin_unlock(&ibmvfc_driver_lock);
        scsi_host_put(vhost->host);
        LEAVE;
-       return 0;
 }
 
 /**

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 29fcc44..77fafb1 100644 (file)
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -2335,7 +2335,7 @@ static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
        return -1;
 }
 
-static int ibmvscsi_remove(struct vio_dev *vdev)
+static void ibmvscsi_remove(struct vio_dev *vdev)
 {
        struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
 
@@ -2356,8 +2356,6 @@ static int ibmvscsi_remove(struct vio_dev *vdev)
        spin_unlock(&ibmvscsi_driver_lock);
 
        scsi_host_put(hostdata->host);
-
-       return 0;
 }
 
 /**

diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
index cc3908c..9abd9e2 100644 (file)
--- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
@@ -3595,7 +3595,7 @@ free_adapter:
        return rc;
 }
 
-static int ibmvscsis_remove(struct vio_dev *vdev)
+static void ibmvscsis_remove(struct vio_dev *vdev)
 {
        struct scsi_info *vscsi = dev_get_drvdata(&vdev->dev);
 
@@ -3622,8 +3622,6 @@ static int ibmvscsis_remove(struct vio_dev *vdev)
        list_del(&vscsi->list);
        spin_unlock_bh(&ibmvscsis_dev_lock);
        kfree(vscsi);
-
-       return 0;
 }
 
 static ssize_t system_id_show(struct device *dev,

diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index c908489..9afa1dc 100644 (file)
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -317,7 +317,6 @@ static void hvcs_hangup(struct tty_struct * tty);
 
 static int hvcs_probe(struct vio_dev *dev,
                const struct vio_device_id *id);
-static int hvcs_remove(struct vio_dev *dev);
 static int __init hvcs_module_init(void);
 static void __exit hvcs_module_exit(void);
 static int hvcs_initialize(void);
@@ -819,7 +818,7 @@ static int hvcs_probe(
        return 0;
 }
 
-static int hvcs_remove(struct vio_dev *dev)
+static void hvcs_remove(struct vio_dev *dev)
 {
        struct hvcs_struct *hvcsd = dev_get_drvdata(&dev->dev);
        unsigned long flags;
@@ -849,7 +848,6 @@ static int hvcs_remove(struct vio_dev *dev)
 
        printk(KERN_INFO "HVCS: vty-server@%X removed from the"
                        " vio bus.\n", dev->unit_address);
-       return 0;
 };
 
 static struct vio_driver hvcs_vio_driver = {