Re: [patch take 2][Intel-IOMMU] Fix for IOMMU early crash

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

> Subject: [Intel-IOMMU] Fix for IOMMU early crash
> 
> pci_dev's->sysdata is highly overloaded and currently
> IOMMU is broken due to IOMMU code depending on this field.
> 
> This patch introduces new field in pci_dev's dev.archdata struct to
> hold IOMMU specific per device IOMMU private data.
> 
> Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>

Looks good. Won't break powerpc.

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> ---
>  drivers/pci/intel-iommu.c   |   22 +++++++++++-----------
>  include/asm-x86_64/device.h |    3 +++
>  2 files changed, 14 insertions(+), 11 deletions(-)
> 
> Index: 2.6-mm/drivers/pci/intel-iommu.c
> ===================================================================
> --- 2.6-mm.orig/drivers/pci/intel-iommu.c	2007-10-04 11:35:09.000000000 -0700
> +++ 2.6-mm/drivers/pci/intel-iommu.c	2007-10-04 11:47:47.000000000 -0700
> @@ -1348,7 +1348,7 @@
>  		list_del(&info->link);
>  		list_del(&info->global);
>  		if (info->dev)
> -			info->dev->sysdata = NULL;
> +			info->dev->dev.archdata.iommu = NULL;
>  		spin_unlock_irqrestore(&device_domain_lock, flags);
>  
>  		detach_domain_for_dev(info->domain, info->bus, info->devfn);
> @@ -1361,7 +1361,7 @@
>  
>  /*
>   * find_domain
> - * Note: we use struct pci_dev->sysdata stores the info
> + * Note: we use struct pci_dev->dev.archdata.iommu stores the info
>   */
>  struct dmar_domain *
>  find_domain(struct pci_dev *pdev)
> @@ -1369,7 +1369,7 @@
>  	struct device_domain_info *info;
>  
>  	/* No lock here, assumes no domain exit in normal case */
> -	info = pdev->sysdata;
> +	info = pdev->dev.archdata.iommu;
>  	if (info)
>  		return info->domain;
>  	return NULL;
> @@ -1519,7 +1519,7 @@
>  	}
>  	list_add(&info->link, &domain->devices);
>  	list_add(&info->global, &device_domain_list);
> -	pdev->sysdata = info;
> +	pdev->dev.archdata.iommu = info;
>  	spin_unlock_irqrestore(&device_domain_lock, flags);
>  	return domain;
>  error:
> @@ -1579,7 +1579,7 @@
>  static inline int iommu_prepare_rmrr_dev(struct dmar_rmrr_unit *rmrr,
>  	struct pci_dev *pdev)
>  {
> -	if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
> +	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
>  		return 0;
>  	return iommu_prepare_identity_map(pdev, rmrr->base_address,
>  		rmrr->end_address + 1);
> @@ -1595,7 +1595,7 @@
>  	int ret;
>  
>  	for_each_pci_dev(pdev) {
> -		if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO ||
> +		if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO ||
>  				!IS_GFX_DEVICE(pdev))
>  			continue;
>  		printk(KERN_INFO "IOMMU: gfx device %s 1-1 mapping\n",
> @@ -1836,7 +1836,7 @@
>  	int prot = 0;
>  
>  	BUG_ON(dir == DMA_NONE);
> -	if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
> +	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
>  		return virt_to_bus(addr);
>  
>  	domain = get_valid_domain_for_dev(pdev);
> @@ -1900,7 +1900,7 @@
>  	unsigned long start_addr;
>  	struct iova *iova;
>  
> -	if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
> +	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
>  		return;
>  	domain = find_domain(pdev);
>  	BUG_ON(!domain);
> @@ -1974,7 +1974,7 @@
>  	size_t size = 0;
>  	void *addr;
>  
> -	if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
> +	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
>  		return;
>  
>  	domain = find_domain(pdev);
> @@ -2032,7 +2032,7 @@
>  	unsigned long start_addr;
>  
>  	BUG_ON(dir == DMA_NONE);
> -	if (pdev->sysdata == DUMMY_DEVICE_DOMAIN_INFO)
> +	if (pdev->dev.archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO)
>  		return intel_nontranslate_map_sg(hwdev, sg, nelems, dir);
>  
>  	domain = get_valid_domain_for_dev(pdev);
> @@ -2234,7 +2234,7 @@
>  		for (i = 0; i < drhd->devices_cnt; i++) {
>  			if (!drhd->devices[i])
>  				continue;
> -			drhd->devices[i]->sysdata = DUMMY_DEVICE_DOMAIN_INFO;
> +			drhd->devices[i]->dev.archdata.iommu = DUMMY_DEVICE_DOMAIN_INFO;
>  		}
>  	}
>  }
> Index: 2.6-mm/include/asm-x86_64/device.h
> ===================================================================
> --- 2.6-mm.orig/include/asm-x86_64/device.h	2007-10-04 11:35:09.000000000 -0700
> +++ 2.6-mm/include/asm-x86_64/device.h	2007-10-04 11:49:44.000000000 -0700
> @@ -10,6 +10,9 @@
>  #ifdef CONFIG_ACPI
>  	void	*acpi_handle;
>  #endif
> +#ifdef CONFIG_DMAR
> +	void *iommu; /* hook for IOMMU specific extension */
> +#endif
>  };
>  
>  #endif /* _ASM_X86_64_DEVICE_H */