diff options
author | Joerg Roedel <joerg.roedel@amd.com> | 2008-09-11 10:24:48 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-09-19 12:59:21 +0200 |
commit | bd60b735c658e6e8c656e89771d281bcfcf51279 (patch) | |
tree | 3587d684e56ed7e057d30b022fa1985990a08939 | |
parent | b39ba6ad004a31bf2a08ba2b08c1e0f9b3530bb7 (diff) | |
download | op-kernel-dev-bd60b735c658e6e8c656e89771d281bcfcf51279.zip op-kernel-dev-bd60b735c658e6e8c656e89771d281bcfcf51279.tar.gz |
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>
-rw-r--r-- | arch/x86/kernel/amd_iommu.c | 43 | ||||
-rw-r--r-- | include/asm-x86/amd_iommu_types.h | 6 |
2 files changed, 44 insertions, 5 deletions
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index a6a6f8e..7c17914 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -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 && @@ -769,6 +774,33 @@ static bool check_device(struct device *dev) } /* + * 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 * requestor id for a given device. @@ -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); } } diff --git a/include/asm-x86/amd_iommu_types.h b/include/asm-x86/amd_iommu_types.h index d8c5a6c..9aa22ea 100644 --- a/include/asm-x86/amd_iommu_types.h +++ b/include/asm-x86/amd_iommu_types.h @@ -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; }; /* |