// SPDX-License-Identifier: GPL-2.0-only

  /*
   * EEH functionality support for VFIO devices. The feature is only
   * available on sPAPR compatible platforms.
   *
   * Copyright Gavin Shan, IBM Corporation 2014.

   */

  #include <linux/module.h>

  #include <linux/uaccess.h>
  #include <linux/vfio.h>
  #include <asm/eeh.h>

  #define DRIVER_VERSION	"0.1"
  #define DRIVER_AUTHOR	"Gavin Shan, IBM Corporation"
  #define DRIVER_DESC	"VFIO IOMMU SPAPR EEH"

  /* We might build address mapping here for "fast" path later */

  void vfio_spapr_pci_eeh_open(struct pci_dev *pdev)

  {

  	eeh_dev_open(pdev);

  }

  EXPORT_SYMBOL_GPL(vfio_spapr_pci_eeh_open);

  
  void vfio_spapr_pci_eeh_release(struct pci_dev *pdev)
  {
  	eeh_dev_release(pdev);
  }

  EXPORT_SYMBOL_GPL(vfio_spapr_pci_eeh_release);

  
  long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
  				unsigned int cmd, unsigned long arg)
  {
  	struct eeh_pe *pe;
  	struct vfio_eeh_pe_op op;
  	unsigned long minsz;
  	long ret = -EINVAL;
  
  	switch (cmd) {
  	case VFIO_CHECK_EXTENSION:
  		if (arg == VFIO_EEH)
  			ret = eeh_enabled() ? 1 : 0;
  		else
  			ret = 0;
  		break;
  	case VFIO_EEH_PE_OP:
  		pe = eeh_iommu_group_to_pe(group);
  		if (!pe)
  			return -ENODEV;
  
  		minsz = offsetofend(struct vfio_eeh_pe_op, op);
  		if (copy_from_user(&op, (void __user *)arg, minsz))
  			return -EFAULT;
  		if (op.argsz < minsz || op.flags)
  			return -EINVAL;
  
  		switch (op.op) {
  		case VFIO_EEH_PE_DISABLE:
  			ret = eeh_pe_set_option(pe, EEH_OPT_DISABLE);
  			break;
  		case VFIO_EEH_PE_ENABLE:
  			ret = eeh_pe_set_option(pe, EEH_OPT_ENABLE);
  			break;
  		case VFIO_EEH_PE_UNFREEZE_IO:
  			ret = eeh_pe_set_option(pe, EEH_OPT_THAW_MMIO);
  			break;
  		case VFIO_EEH_PE_UNFREEZE_DMA:
  			ret = eeh_pe_set_option(pe, EEH_OPT_THAW_DMA);
  			break;
  		case VFIO_EEH_PE_GET_STATE:
  			ret = eeh_pe_get_state(pe);
  			break;
  		case VFIO_EEH_PE_RESET_DEACTIVATE:

  			ret = eeh_pe_reset(pe, EEH_RESET_DEACTIVATE, true);

  			break;
  		case VFIO_EEH_PE_RESET_HOT:

  			ret = eeh_pe_reset(pe, EEH_RESET_HOT, true);

  			break;
  		case VFIO_EEH_PE_RESET_FUNDAMENTAL:

  			ret = eeh_pe_reset(pe, EEH_RESET_FUNDAMENTAL, true);

  			break;
  		case VFIO_EEH_PE_CONFIGURE:
  			ret = eeh_pe_configure(pe);
  			break;

  		case VFIO_EEH_PE_INJECT_ERR:
  			minsz = offsetofend(struct vfio_eeh_pe_op, err.mask);
  			if (op.argsz < minsz)
  				return -EINVAL;
  			if (copy_from_user(&op, (void __user *)arg, minsz))
  				return -EFAULT;
  
  			ret = eeh_pe_inject_err(pe, op.err.type, op.err.func,
  						op.err.addr, op.err.mask);
  			break;

  		default:
  			ret = -EINVAL;
  		}
  	}
  
  	return ret;
  }

  EXPORT_SYMBOL_GPL(vfio_spapr_iommu_eeh_ioctl);

  
  MODULE_VERSION(DRIVER_VERSION);
  MODULE_LICENSE("GPL v2");
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC);