s390/cio: Convert ccw_io_region to pointer

In the event that we want to change the layout of the ccw_io_region in the
future[1], it might be easier to work with it as a pointer within the
vfio_ccw_private struct rather than an embedded struct.

[1] https://patchwork.kernel.org/comment/22228541/

Signed-off-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20180921204013.95804-2-farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
index 770fa9c..f48e6f8 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_drv.c
+++ b/drivers/s390/cio/vfio_ccw_drv.c
@@ -79,7 +79,7 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
                cp_update_scsw(&private->cp, &irb->scsw);
                cp_free(&private->cp);
        }
-       memcpy(private->io_region.irb_area, irb, sizeof(*irb));
+       memcpy(private->io_region->irb_area, irb, sizeof(*irb));
 
        if (private->io_trigger)
                eventfd_signal(private->io_trigger, 1);
@@ -114,6 +114,14 @@ static int vfio_ccw_sch_probe(struct subchannel *sch)
        private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
        if (!private)
                return -ENOMEM;
+
+       private->io_region = kzalloc(sizeof(*private->io_region),
+                                    GFP_KERNEL | GFP_DMA);
+       if (!private->io_region) {
+               kfree(private);
+               return -ENOMEM;
+       }
+
        private->sch = sch;
        dev_set_drvdata(&sch->dev, private);
 
@@ -139,6 +147,7 @@ out_disable:
        cio_disable_subchannel(sch);
 out_free:
        dev_set_drvdata(&sch->dev, NULL);
+       kfree(private->io_region);
        kfree(private);
        return ret;
 }
@@ -153,6 +162,7 @@ static int vfio_ccw_sch_remove(struct subchannel *sch)
 
        dev_set_drvdata(&sch->dev, NULL);
 
+       kfree(private->io_region);
        kfree(private);
 
        return 0;

diff --git a/drivers/s390/cio/vfio_ccw_fsm.c b/drivers/s390/cio/vfio_ccw_fsm.c
index 797a827..f94aa01 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_fsm.c
+++ b/drivers/s390/cio/vfio_ccw_fsm.c
@@ -93,13 +93,13 @@ static void fsm_io_error(struct vfio_ccw_private *private,
                         enum vfio_ccw_event event)
 {
        pr_err("vfio-ccw: FSM: I/O request from state:%d\n", private->state);
-       private->io_region.ret_code = -EIO;
+       private->io_region->ret_code = -EIO;
 }
 
 static void fsm_io_busy(struct vfio_ccw_private *private,
                        enum vfio_ccw_event event)
 {
-       private->io_region.ret_code = -EBUSY;
+       private->io_region->ret_code = -EBUSY;
 }
 
 static void fsm_disabled_irq(struct vfio_ccw_private *private,
@@ -126,7 +126,7 @@ static void fsm_io_request(struct vfio_ccw_private *private,
 {
        union orb *orb;
        union scsw *scsw = &private->scsw;
-       struct ccw_io_region *io_region = &private->io_region;
+       struct ccw_io_region *io_region = private->io_region;
        struct mdev_device *mdev = private->mdev;
        char *errstr = "request";
 

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 41eeb57..f673e10 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -174,7 +174,7 @@ static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev,
                return -EINVAL;
 
        private = dev_get_drvdata(mdev_parent_dev(mdev));
-       region = &private->io_region;
+       region = private->io_region;
        if (copy_to_user(buf, (void *)region + *ppos, count))
                return -EFAULT;
 
@@ -196,7 +196,7 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev,
        if (private->state != VFIO_CCW_STATE_IDLE)
                return -EACCES;
 
-       region = &private->io_region;
+       region = private->io_region;
        if (copy_from_user((void *)region + *ppos, buf, count))
                return -EFAULT;
 

diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
index 78a66d9..078e46f 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_private.h
+++ b/drivers/s390/cio/vfio_ccw_private.h
@@ -41,7 +41,7 @@ struct vfio_ccw_private {
        atomic_t                avail;
        struct mdev_device      *mdev;
        struct notifier_block   nb;
-       struct ccw_io_region    io_region;
+       struct ccw_io_region    *io_region;
 
        struct channel_program  cp;
        struct irb              irb;