From: Joerg Roedel <[email protected]> This patch changes the behavior of the iommu_attach_device and iommu_detach_device functions. With this change these functions only work on devices that have their own group. For all other devices the iommu_group_attach/detach functions must be used.
Signed-off-by: Joerg Roedel <[email protected]> --- drivers/iommu/iommu.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 67 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index fbfc015..adeedd2 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -433,6 +433,17 @@ void iommu_group_remove_device(struct device *dev) } EXPORT_SYMBOL_GPL(iommu_group_remove_device); +static int iommu_group_device_count(struct iommu_group *group) +{ + struct iommu_device *entry; + int ret = 0; + + list_for_each_entry(entry, &group->devices, list) + ret++; + + return ret; +} + /** * iommu_group_for_each_dev - iterate over each device in the group * @group: the group @@ -970,7 +981,8 @@ void iommu_domain_free(struct iommu_domain *domain) } EXPORT_SYMBOL_GPL(iommu_domain_free); -int iommu_attach_device(struct iommu_domain *domain, struct device *dev) +static int __iommu_attach_device(struct iommu_domain *domain, + struct device *dev) { int ret; if (unlikely(domain->ops->attach_dev == NULL)) @@ -981,9 +993,38 @@ int iommu_attach_device(struct iommu_domain *domain, struct device *dev) trace_attach_device_to_domain(dev); return ret; } + +int iommu_attach_device(struct iommu_domain *domain, struct device *dev) +{ + struct iommu_group *group; + int ret; + + group = iommu_group_get(dev); + /* FIXME: Remove this when groups a mandatory for iommu drivers */ + if (group == NULL) + return __iommu_attach_device(domain, dev); + + /* + * We have a group - lock it to make sure the device-count doesn't + * change while we are attaching + */ + mutex_lock(&group->mutex); + ret = -EINVAL; + if (iommu_group_device_count(group) != 1) + goto out_unlock; + + ret = __iommu_attach_device(domain, dev); + +out_unlock: + mutex_unlock(&group->mutex); + iommu_group_put(group); + + return ret; +} EXPORT_SYMBOL_GPL(iommu_attach_device); -void iommu_detach_device(struct iommu_domain *domain, struct device *dev) +static void __iommu_detach_device(struct iommu_domain *domain, + struct device *dev) { if (unlikely(domain->ops->detach_dev == NULL)) return; @@ -991,6 +1032,28 @@ void iommu_detach_device(struct iommu_domain *domain, struct device *dev) domain->ops->detach_dev(domain, dev); trace_detach_device_from_domain(dev); } + +void iommu_detach_device(struct iommu_domain *domain, struct device *dev) +{ + struct iommu_group *group; + + group = iommu_group_get(dev); + /* FIXME: Remove this when groups a mandatory for iommu drivers */ + if (group == NULL) + return __iommu_detach_device(domain, dev); + + mutex_lock(&group->mutex); + if (iommu_group_device_count(group) != 1) { + WARN_ON(1); + goto out_unlock; + } + + __iommu_detach_device(domain, dev); + +out_unlock: + mutex_unlock(&group->mutex); + iommu_group_put(group); +} EXPORT_SYMBOL_GPL(iommu_detach_device); /* @@ -1007,7 +1070,7 @@ static int iommu_group_do_attach_device(struct device *dev, void *data) { struct iommu_domain *domain = data; - return iommu_attach_device(domain, dev); + return __iommu_attach_device(domain, dev); } int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group) @@ -1021,7 +1084,7 @@ static int iommu_group_do_detach_device(struct device *dev, void *data) { struct iommu_domain *domain = data; - iommu_detach_device(domain, dev); + __iommu_detach_device(domain, dev); return 0; } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
