151 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			151 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Channel path related status regions for vfio_ccw
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|  *
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|  * Copyright IBM Corp. 2020
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|  *
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|  * Author(s): Farhan Ali <alifm@linux.ibm.com>
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|  *            Eric Farman <farman@linux.ibm.com>
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|  */
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| 
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| #include <linux/slab.h>
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| #include <linux/vfio.h>
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| #include "vfio_ccw_private.h"
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| 
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| static ssize_t vfio_ccw_schib_region_read(struct vfio_ccw_private *private,
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| 					  char __user *buf, size_t count,
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| 					  loff_t *ppos)
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| {
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| 	struct subchannel *sch = to_subchannel(private->vdev.dev->parent);
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| 	unsigned int i = VFIO_CCW_OFFSET_TO_INDEX(*ppos) - VFIO_CCW_NUM_REGIONS;
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| 	loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
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| 	struct ccw_schib_region *region;
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| 	int ret;
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| 
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| 	if (pos + count > sizeof(*region))
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| 		return -EINVAL;
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| 
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| 	mutex_lock(&private->io_mutex);
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| 	region = private->region[i].data;
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| 
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| 	if (cio_update_schib(sch)) {
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| 		ret = -ENODEV;
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| 		goto out;
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| 	}
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| 
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| 	memcpy(region, &sch->schib, sizeof(*region));
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| 
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| 	if (copy_to_user(buf, (void *)region + pos, count)) {
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| 		ret = -EFAULT;
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| 		goto out;
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| 	}
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| 
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| 	ret = count;
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| 
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| out:
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| 	mutex_unlock(&private->io_mutex);
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| 	return ret;
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| }
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| 
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| static ssize_t vfio_ccw_schib_region_write(struct vfio_ccw_private *private,
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| 					   const char __user *buf, size_t count,
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| 					   loff_t *ppos)
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| {
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| 	return -EINVAL;
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| }
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| 
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| 
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| static void vfio_ccw_schib_region_release(struct vfio_ccw_private *private,
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| 					  struct vfio_ccw_region *region)
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| {
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| 
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| }
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| 
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| static const struct vfio_ccw_regops vfio_ccw_schib_region_ops = {
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| 	.read = vfio_ccw_schib_region_read,
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| 	.write = vfio_ccw_schib_region_write,
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| 	.release = vfio_ccw_schib_region_release,
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| };
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| 
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| int vfio_ccw_register_schib_dev_regions(struct vfio_ccw_private *private)
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| {
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| 	return vfio_ccw_register_dev_region(private,
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| 					    VFIO_REGION_SUBTYPE_CCW_SCHIB,
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| 					    &vfio_ccw_schib_region_ops,
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| 					    sizeof(struct ccw_schib_region),
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| 					    VFIO_REGION_INFO_FLAG_READ,
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| 					    private->schib_region);
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| }
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| 
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| static ssize_t vfio_ccw_crw_region_read(struct vfio_ccw_private *private,
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| 					char __user *buf, size_t count,
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| 					loff_t *ppos)
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| {
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| 	unsigned int i = VFIO_CCW_OFFSET_TO_INDEX(*ppos) - VFIO_CCW_NUM_REGIONS;
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| 	loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK;
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| 	struct ccw_crw_region *region;
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| 	struct vfio_ccw_crw *crw;
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| 	int ret;
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| 
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| 	if (pos + count > sizeof(*region))
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| 		return -EINVAL;
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| 
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| 	crw = list_first_entry_or_null(&private->crw,
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| 				       struct vfio_ccw_crw, next);
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| 
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| 	if (crw)
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| 		list_del(&crw->next);
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| 
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| 	mutex_lock(&private->io_mutex);
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| 	region = private->region[i].data;
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| 
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| 	if (crw)
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| 		memcpy(®ion->crw, &crw->crw, sizeof(region->crw));
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| 
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| 	if (copy_to_user(buf, (void *)region + pos, count))
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| 		ret = -EFAULT;
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| 	else
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| 		ret = count;
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| 
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| 	region->crw = 0;
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| 
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| 	mutex_unlock(&private->io_mutex);
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| 
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| 	kfree(crw);
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| 
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| 	/* Notify the guest if more CRWs are on our queue */
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| 	if (!list_empty(&private->crw) && private->crw_trigger)
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| 		eventfd_signal(private->crw_trigger);
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| 
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| 	return ret;
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| }
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| 
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| static ssize_t vfio_ccw_crw_region_write(struct vfio_ccw_private *private,
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| 					 const char __user *buf, size_t count,
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| 					 loff_t *ppos)
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| {
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| 	return -EINVAL;
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| }
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| 
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| static void vfio_ccw_crw_region_release(struct vfio_ccw_private *private,
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| 					struct vfio_ccw_region *region)
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| {
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| 
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| }
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| 
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| static const struct vfio_ccw_regops vfio_ccw_crw_region_ops = {
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| 	.read = vfio_ccw_crw_region_read,
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| 	.write = vfio_ccw_crw_region_write,
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| 	.release = vfio_ccw_crw_region_release,
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| };
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| 
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| int vfio_ccw_register_crw_dev_regions(struct vfio_ccw_private *private)
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| {
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| 	return vfio_ccw_register_dev_region(private,
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| 					    VFIO_REGION_SUBTYPE_CCW_CRW,
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| 					    &vfio_ccw_crw_region_ops,
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| 					    sizeof(struct ccw_crw_region),
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| 					    VFIO_REGION_INFO_FLAG_READ,
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| 					    private->crw_region);
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| }
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