mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
AMD IOMMU: don't assign preallocated protection domains to devices
In isolation mode the protection domains for the devices are preallocated and preassigned. This is bad if a device should be passed to a virtualization guest because the IOMMU code does not know if it is in use by a driver. This patch changes the code to assign the device to the preallocated domain only if there are dma mapping requests for it. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
parent
b39ba6ad00
commit
bd60b735c6
2 changed files with 44 additions and 5 deletions
|
@ -33,6 +33,10 @@
|
|||
|
||||
static DEFINE_RWLOCK(amd_iommu_devtable_lock);
|
||||
|
||||
/* A list of preallocated protection domains */
|
||||
static LIST_HEAD(iommu_pd_list);
|
||||
static DEFINE_SPINLOCK(iommu_pd_list_lock);
|
||||
|
||||
/*
|
||||
* general struct to manage commands send to an IOMMU
|
||||
*/
|
||||
|
@ -663,6 +667,7 @@ static struct dma_ops_domain *dma_ops_domain_alloc(struct amd_iommu *iommu,
|
|||
dma_dom->next_bit = 0;
|
||||
|
||||
dma_dom->need_flush = false;
|
||||
dma_dom->target_dev = 0xffff;
|
||||
|
||||
/* Intialize the exclusion range if necessary */
|
||||
if (iommu->exclusion_start &&
|
||||
|
@ -768,6 +773,33 @@ static bool check_device(struct device *dev)
|
|||
return true;
|
||||
}
|
||||
|
||||
/*
|
||||
* In this function the list of preallocated protection domains is traversed to
|
||||
* find the domain for a specific device
|
||||
*/
|
||||
static struct dma_ops_domain *find_protection_domain(u16 devid)
|
||||
{
|
||||
struct dma_ops_domain *entry, *ret = NULL;
|
||||
unsigned long flags;
|
||||
|
||||
if (list_empty(&iommu_pd_list))
|
||||
return NULL;
|
||||
|
||||
spin_lock_irqsave(&iommu_pd_list_lock, flags);
|
||||
|
||||
list_for_each_entry(entry, &iommu_pd_list, list) {
|
||||
if (entry->target_dev == devid) {
|
||||
ret = entry;
|
||||
list_del(&ret->list);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
spin_unlock_irqrestore(&iommu_pd_list_lock, flags);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* In the dma_ops path we only have the struct device. This function
|
||||
* finds the corresponding IOMMU, the protection domain and the
|
||||
|
@ -803,9 +835,11 @@ static int get_device_resources(struct device *dev,
|
|||
*iommu = amd_iommu_rlookup_table[*bdf];
|
||||
if (*iommu == NULL)
|
||||
return 0;
|
||||
dma_dom = (*iommu)->default_dom;
|
||||
*domain = domain_for_device(*bdf);
|
||||
if (*domain == NULL) {
|
||||
dma_dom = find_protection_domain(*bdf);
|
||||
if (!dma_dom)
|
||||
dma_dom = (*iommu)->default_dom;
|
||||
*domain = &dma_dom->domain;
|
||||
set_device_domain(*iommu, *domain, *bdf);
|
||||
printk(KERN_INFO "AMD IOMMU: Using protection domain %d for "
|
||||
|
@ -1257,10 +1291,9 @@ void prealloc_protection_domains(void)
|
|||
if (!dma_dom)
|
||||
continue;
|
||||
init_unity_mappings_for_device(dma_dom, devid);
|
||||
set_device_domain(iommu, &dma_dom->domain, devid);
|
||||
printk(KERN_INFO "AMD IOMMU: Allocated domain %d for device ",
|
||||
dma_dom->domain.id);
|
||||
print_devid(devid, 1);
|
||||
dma_dom->target_dev = devid;
|
||||
|
||||
list_add_tail(&dma_dom->list, &iommu_pd_list);
|
||||
}
|
||||
}
|
||||
|
||||
|
|
|
@ -227,6 +227,12 @@ struct dma_ops_domain {
|
|||
|
||||
/* This will be set to true when TLB needs to be flushed */
|
||||
bool need_flush;
|
||||
|
||||
/*
|
||||
* if this is a preallocated domain, keep the device for which it was
|
||||
* preallocated in this variable
|
||||
*/
|
||||
u16 target_dev;
|
||||
};
|
||||
|
||||
/*
|
||||
|
|
Loading…
Reference in a new issue