From 2b02b091ab3d1685926bfc76486bf7a22d92979a Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Thu, 9 Jun 2011 17:48:39 +0200 Subject: [PATCH] x86/amd-iommu: Allow dev_data->alias to be NULL Let dev_data->alias be just NULL if the device has no alias. Signed-off-by: Joerg Roedel --- arch/x86/kernel/amd_iommu.c | 77 ++++++++++++++++++++----------------- 1 file changed, 41 insertions(+), 36 deletions(-) diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index a15a17231909..2d914a49b19a 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -183,12 +183,14 @@ static int iommu_init_device(struct device *dev) return -ENOMEM; alias = amd_iommu_alias_table[dev_data->devid]; - pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff); - if (pdev) - dev_data->alias = &pdev->dev; - else { - free_dev_data(dev_data); - return -ENOTSUPP; + if (alias != dev_data->devid) { + pdev = pci_get_bus_and_slot(PCI_BUS(alias), alias & 0xff); + if (pdev) + dev_data->alias = &pdev->dev; + else { + free_dev_data(dev_data); + return -ENOTSUPP; + } } dev->archdata.iommu = dev_data; @@ -1604,29 +1606,31 @@ static void do_detach(struct iommu_dev_data *dev_data) static int __attach_device(struct iommu_dev_data *dev_data, struct protection_domain *domain) { - struct iommu_dev_data *alias_data; int ret; - alias_data = get_dev_data(dev_data->alias); - - if (!alias_data) - return -EINVAL; - /* lock domain */ spin_lock(&domain->lock); - /* Some sanity checks */ - ret = -EBUSY; - if (alias_data->domain != NULL && - alias_data->domain != domain) - goto out_unlock; + if (dev_data->alias != NULL) { + struct iommu_dev_data *alias_data; + + alias_data = get_dev_data(dev_data->alias); + + ret = -EINVAL; + if (!alias_data) + goto out_unlock; - if (dev_data->domain != NULL && - dev_data->domain != domain) - goto out_unlock; + /* Some sanity checks */ + ret = -EBUSY; + if (alias_data->domain != NULL && + alias_data->domain != domain) + goto out_unlock; - /* Do real assignment */ - if (dev_data->devid != alias_data->devid) { + if (dev_data->domain != NULL && + dev_data->domain != domain) + goto out_unlock; + + /* Do real assignment */ if (alias_data->domain == NULL) do_attach(alias_data, domain); @@ -1696,8 +1700,8 @@ static void __detach_device(struct iommu_dev_data *dev_data) spin_lock_irqsave(&domain->lock, flags); - alias_data = get_dev_data(dev_data->alias); - if (dev_data->devid != alias_data->devid) { + if (dev_data->alias) { + alias_data = get_dev_data(dev_data->alias); if (atomic_dec_and_test(&alias_data->bind)) do_detach(alias_data); } @@ -1744,24 +1748,25 @@ static void detach_device(struct device *dev) */ static struct protection_domain *domain_for_device(struct device *dev) { - struct protection_domain *dom; struct iommu_dev_data *dev_data, *alias_data; + struct protection_domain *dom = NULL; unsigned long flags; dev_data = get_dev_data(dev); - alias_data = get_dev_data(dev_data->alias); - if (!alias_data) - return NULL; - read_lock_irqsave(&amd_iommu_devtable_lock, flags); - dom = dev_data->domain; - if (dom == NULL && - alias_data->domain != NULL) { - __attach_device(dev_data, alias_data->domain); - dom = alias_data->domain; - } + if (dev_data->domain) + return dev_data->domain; - read_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + if (dev_data->alias != NULL) { + alias_data = get_dev_data(dev_data->alias); + + read_lock_irqsave(&amd_iommu_devtable_lock, flags); + if (alias_data->domain != NULL) { + __attach_device(dev_data, alias_data->domain); + dom = alias_data->domain; + } + read_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + } return dom; } -- 2.34.1