diff options
author | Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> | 2017-03-17 04:17:34 +0100 |
---|---|---|
committer | Cornelia Huck <cornelia.huck@de.ibm.com> | 2017-03-31 12:55:06 +0200 |
commit | 060d2b5afcc4f9e2d61e2b059e648f569b8dba9a (patch) | |
tree | c33cfb0c149782f539391e3cbcc4cd021eb6886b /drivers | |
parent | 84cd8fc48478b5e67b3f1600717299e11430a67e (diff) | |
download | op-kernel-dev-060d2b5afcc4f9e2d61e2b059e648f569b8dba9a.zip op-kernel-dev-060d2b5afcc4f9e2d61e2b059e648f569b8dba9a.tar.gz |
vfio: ccw: introduce ccw_io_region
To provide user-space a set of interfaces to:
1. pass in a ccw program to perform an I/O operation.
2. read back I/O results of the completed I/O operations.
We introduce an MMIO region for the vfio-ccw device here.
This region is defined to content:
1. areas to store arguments that an ssch required.
2. areas to store the I/O results.
Using pwrite/pread to the device on this region, a user-space program
could write/read data to/from the vfio-ccw device.
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170317031743.40128-8-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/s390/cio/vfio_ccw_ops.c | 47 | ||||
-rw-r--r-- | drivers/s390/cio/vfio_ccw_private.h | 4 |
2 files changed, 51 insertions, 0 deletions
diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index b8a2fed..6c06805 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -127,6 +127,51 @@ void vfio_ccw_mdev_release(struct mdev_device *mdev) &private->nb); } +static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev, + char __user *buf, + size_t count, + loff_t *ppos) +{ + struct vfio_ccw_private *private; + struct ccw_io_region *region; + + if (*ppos + count > sizeof(*region)) + return -EINVAL; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + if (!private) + return -ENODEV; + + region = &private->io_region; + if (copy_to_user(buf, (void *)region + *ppos, count)) + return -EFAULT; + + return count; +} + +static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, + const char __user *buf, + size_t count, + loff_t *ppos) +{ + struct vfio_ccw_private *private; + struct ccw_io_region *region; + + if (*ppos + count > sizeof(*region)) + return -EINVAL; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + if (!private) + return -ENODEV; + + region = &private->io_region; + if (copy_from_user((void *)region + *ppos, buf, count)) + return -EFAULT; + region->ret_code = 0; + + return count; +} + static const struct mdev_parent_ops vfio_ccw_mdev_ops = { .owner = THIS_MODULE, .supported_type_groups = mdev_type_groups, @@ -134,6 +179,8 @@ static const struct mdev_parent_ops vfio_ccw_mdev_ops = { .remove = vfio_ccw_mdev_remove, .open = vfio_ccw_mdev_open, .release = vfio_ccw_mdev_release, + .read = vfio_ccw_mdev_read, + .write = vfio_ccw_mdev_write, }; int vfio_ccw_mdev_reg(struct subchannel *sch) diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h index 5afb3ba..359e96b 100644 --- a/drivers/s390/cio/vfio_ccw_private.h +++ b/drivers/s390/cio/vfio_ccw_private.h @@ -10,6 +10,8 @@ #ifndef _VFIO_CCW_PRIVATE_H_ #define _VFIO_CCW_PRIVATE_H_ +#include <linux/vfio_ccw.h> + #include "css.h" /** @@ -19,6 +21,7 @@ * @avail: available for creating a mediated device * @mdev: pointer to the mediated device * @nb: notifier for vfio events + * @io_region: MMIO region to input/output I/O arguments/results */ struct vfio_ccw_private { struct subchannel *sch; @@ -26,6 +29,7 @@ struct vfio_ccw_private { atomic_t avail; struct mdev_device *mdev; struct notifier_block nb; + struct ccw_io_region io_region; } __aligned(8); extern int vfio_ccw_mdev_reg(struct subchannel *sch); |