vfio/ccw: Pass vfio_ccw_private not mdev_device to various functions

mdev_device should only be used in functions assigned to ops callbacks,
interior functions should use the struct vfio_ccw_private instead of
repeatedly trying to get it from the mdev.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-cea4f5bd2c00+b52-ccw_mdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
index 7f540ad0b568bc36e08233c31ae025c15b1a7b6c..1edbea9de0ec422d082793389b36b9ea724cfc26 100644 (file)
--- a/drivers/s390/cio/vfio_ccw_ops.c
+++ b/drivers/s390/cio/vfio_ccw_ops.c
@@ -17,13 +17,11 @@
 
 #include "vfio_ccw_private.h"
 
-static int vfio_ccw_mdev_reset(struct mdev_device *mdev)
+static int vfio_ccw_mdev_reset(struct vfio_ccw_private *private)
 {
-       struct vfio_ccw_private *private;
        struct subchannel *sch;
        int ret;
 
-       private = dev_get_drvdata(mdev_parent_dev(mdev));
        sch = private->sch;
        /*
         * TODO:
@@ -61,7 +59,7 @@ static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
                if (!cp_iova_pinned(&private->cp, unmap->iova))
                        return NOTIFY_OK;
 
-               if (vfio_ccw_mdev_reset(private->mdev))
+               if (vfio_ccw_mdev_reset(private))
                        return NOTIFY_BAD;
 
                cp_free(&private->cp);
@@ -201,7 +199,7 @@ static void vfio_ccw_mdev_close_device(struct mdev_device *mdev)
 
        if ((private->state != VFIO_CCW_STATE_NOT_OPER) &&
            (private->state != VFIO_CCW_STATE_STANDBY)) {
-               if (!vfio_ccw_mdev_reset(mdev))
+               if (!vfio_ccw_mdev_reset(private))
                        private->state = VFIO_CCW_STATE_STANDBY;
                /* The state will be NOT_OPER on error. */
        }
@@ -311,12 +309,9 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev,
        return -EINVAL;
 }
 
-static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info,
-                                        struct mdev_device *mdev)
+static int vfio_ccw_mdev_get_device_info(struct vfio_ccw_private *private,
+                                        struct vfio_device_info *info)
 {
-       struct vfio_ccw_private *private;
-
-       private = dev_get_drvdata(mdev_parent_dev(mdev));
        info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET;
        info->num_regions = VFIO_CCW_NUM_REGIONS + private->num_regions;
        info->num_irqs = VFIO_CCW_NUM_IRQS;
@@ -324,14 +319,12 @@ static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info,
        return 0;
 }
 
-static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info,
-                                        struct mdev_device *mdev,
+static int vfio_ccw_mdev_get_region_info(struct vfio_ccw_private *private,
+                                        struct vfio_region_info *info,
                                         unsigned long arg)
 {
-       struct vfio_ccw_private *private;
        int i;
 
-       private = dev_get_drvdata(mdev_parent_dev(mdev));
        switch (info->index) {
        case VFIO_CCW_CONFIG_REGION_INDEX:
                info->offset = 0;
@@ -406,19 +399,16 @@ static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info)
        return 0;
 }
 
-static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev,
+static int vfio_ccw_mdev_set_irqs(struct vfio_ccw_private *private,
                                  uint32_t flags,
                                  uint32_t index,
                                  void __user *data)
 {
-       struct vfio_ccw_private *private;
        struct eventfd_ctx **ctx;
 
        if (!(flags & VFIO_IRQ_SET_ACTION_TRIGGER))
                return -EINVAL;
 
-       private = dev_get_drvdata(mdev_parent_dev(mdev));
-
        switch (index) {
        case VFIO_CCW_IO_IRQ_INDEX:
                ctx = &private->io_trigger;
@@ -524,6 +514,8 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
                                   unsigned int cmd,
                                   unsigned long arg)
 {
+       struct vfio_ccw_private *private =
+               dev_get_drvdata(mdev_parent_dev(mdev));
        int ret = 0;
        unsigned long minsz;
 
@@ -540,7 +532,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
                if (info.argsz < minsz)
                        return -EINVAL;
 
-               ret = vfio_ccw_mdev_get_device_info(&info, mdev);
+               ret = vfio_ccw_mdev_get_device_info(private, &info);
                if (ret)
                        return ret;
 
@@ -558,7 +550,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
                if (info.argsz < minsz)
                        return -EINVAL;
 
-               ret = vfio_ccw_mdev_get_region_info(&info, mdev, arg);
+               ret = vfio_ccw_mdev_get_region_info(private, &info, arg);
                if (ret)
                        return ret;
 
@@ -603,10 +595,11 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev,
                        return ret;
 
                data = (void __user *)(arg + minsz);
-               return vfio_ccw_mdev_set_irqs(mdev, hdr.flags, hdr.index, data);
+               return vfio_ccw_mdev_set_irqs(private, hdr.flags, hdr.index,
+                                             data);
        }
        case VFIO_DEVICE_RESET:
-               return vfio_ccw_mdev_reset(mdev);
+               return vfio_ccw_mdev_reset(private);
        default:
                return -ENOTTY;
        }