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Diffstat (limited to 'drivers/iommu/amd_iommu.c')
-rw-r--r--drivers/iommu/amd_iommu.c398
1 files changed, 248 insertions, 150 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 8b2be1e7714f..e5e223938eec 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -35,6 +35,7 @@
#include <linux/msi.h>
#include <linux/dma-contiguous.h>
#include <linux/irqdomain.h>
+#include <linux/percpu.h>
#include <asm/irq_remapping.h>
#include <asm/io_apic.h>
#include <asm/apic.h>
@@ -114,6 +115,45 @@ struct kmem_cache *amd_iommu_irq_cache;
static void update_domain(struct protection_domain *domain);
static int protection_domain_init(struct protection_domain *domain);
+/*
+ * For dynamic growth the aperture size is split into ranges of 128MB of
+ * DMA address space each. This struct represents one such range.
+ */
+struct aperture_range {
+
+ spinlock_t bitmap_lock;
+
+ /* address allocation bitmap */
+ unsigned long *bitmap;
+ unsigned long offset;
+ unsigned long next_bit;
+
+ /*
+ * Array of PTE pages for the aperture. In this array we save all the
+ * leaf pages of the domain page table used for the aperture. This way
+ * we don't need to walk the page table to find a specific PTE. We can
+ * just calculate its address in constant time.
+ */
+ u64 *pte_pages[64];
+};
+
+/*
+ * Data container for a dma_ops specific protection domain
+ */
+struct dma_ops_domain {
+ /* generic protection domain information */
+ struct protection_domain domain;
+
+ /* size of the aperture for the mappings */
+ unsigned long aperture_size;
+
+ /* aperture index we start searching for free addresses */
+ u32 __percpu *next_index;
+
+ /* address space relevant data */
+ struct aperture_range *aperture[APERTURE_MAX_RANGES];
+};
+
/****************************************************************************
*
* Helper functions
@@ -1167,11 +1207,21 @@ static u64 *alloc_pte(struct protection_domain *domain,
end_lvl = PAGE_SIZE_LEVEL(page_size);
while (level > end_lvl) {
- if (!IOMMU_PTE_PRESENT(*pte)) {
+ u64 __pte, __npte;
+
+ __pte = *pte;
+
+ if (!IOMMU_PTE_PRESENT(__pte)) {
page = (u64 *)get_zeroed_page(gfp);
if (!page)
return NULL;
- *pte = PM_LEVEL_PDE(level, virt_to_phys(page));
+
+ __npte = PM_LEVEL_PDE(level, virt_to_phys(page));
+
+ if (cmpxchg64(pte, __pte, __npte)) {
+ free_page((unsigned long)page);
+ continue;
+ }
}
/* No level skipping support yet */
@@ -1376,8 +1426,10 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
bool populate, gfp_t gfp)
{
int index = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
- struct amd_iommu *iommu;
unsigned long i, old_size, pte_pgsize;
+ struct aperture_range *range;
+ struct amd_iommu *iommu;
+ unsigned long flags;
#ifdef CONFIG_IOMMU_STRESS
populate = false;
@@ -1386,15 +1438,17 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
if (index >= APERTURE_MAX_RANGES)
return -ENOMEM;
- dma_dom->aperture[index] = kzalloc(sizeof(struct aperture_range), gfp);
- if (!dma_dom->aperture[index])
+ range = kzalloc(sizeof(struct aperture_range), gfp);
+ if (!range)
return -ENOMEM;
- dma_dom->aperture[index]->bitmap = (void *)get_zeroed_page(gfp);
- if (!dma_dom->aperture[index]->bitmap)
+ range->bitmap = (void *)get_zeroed_page(gfp);
+ if (!range->bitmap)
goto out_free;
- dma_dom->aperture[index]->offset = dma_dom->aperture_size;
+ range->offset = dma_dom->aperture_size;
+
+ spin_lock_init(&range->bitmap_lock);
if (populate) {
unsigned long address = dma_dom->aperture_size;
@@ -1407,14 +1461,20 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
if (!pte)
goto out_free;
- dma_dom->aperture[index]->pte_pages[i] = pte_page;
+ range->pte_pages[i] = pte_page;
address += APERTURE_RANGE_SIZE / 64;
}
}
- old_size = dma_dom->aperture_size;
- dma_dom->aperture_size += APERTURE_RANGE_SIZE;
+ spin_lock_irqsave(&dma_dom->domain.lock, flags);
+
+ /* First take the bitmap_lock and then publish the range */
+ spin_lock(&range->bitmap_lock);
+
+ old_size = dma_dom->aperture_size;
+ dma_dom->aperture[index] = range;
+ dma_dom->aperture_size += APERTURE_RANGE_SIZE;
/* Reserve address range used for MSI messages */
if (old_size < MSI_ADDR_BASE_LO &&
@@ -1461,62 +1521,123 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
update_domain(&dma_dom->domain);
+ spin_unlock(&range->bitmap_lock);
+
+ spin_unlock_irqrestore(&dma_dom->domain.lock, flags);
+
return 0;
out_free:
update_domain(&dma_dom->domain);
- free_page((unsigned long)dma_dom->aperture[index]->bitmap);
+ free_page((unsigned long)range->bitmap);
- kfree(dma_dom->aperture[index]);
- dma_dom->aperture[index] = NULL;
+ kfree(range);
return -ENOMEM;
}
+static dma_addr_t dma_ops_aperture_alloc(struct dma_ops_domain *dom,
+ struct aperture_range *range,
+ unsigned long pages,
+ unsigned long dma_mask,
+ unsigned long boundary_size,
+ unsigned long align_mask,
+ bool trylock)
+{
+ unsigned long offset, limit, flags;
+ dma_addr_t address;
+ bool flush = false;
+
+ offset = range->offset >> PAGE_SHIFT;
+ limit = iommu_device_max_index(APERTURE_RANGE_PAGES, offset,
+ dma_mask >> PAGE_SHIFT);
+
+ if (trylock) {
+ if (!spin_trylock_irqsave(&range->bitmap_lock, flags))
+ return -1;
+ } else {
+ spin_lock_irqsave(&range->bitmap_lock, flags);
+ }
+
+ address = iommu_area_alloc(range->bitmap, limit, range->next_bit,
+ pages, offset, boundary_size, align_mask);
+ if (address == -1) {
+ /* Nothing found, retry one time */
+ address = iommu_area_alloc(range->bitmap, limit,
+ 0, pages, offset, boundary_size,
+ align_mask);
+ flush = true;
+ }
+
+ if (address != -1)
+ range->next_bit = address + pages;
+
+ spin_unlock_irqrestore(&range->bitmap_lock, flags);
+
+ if (flush) {
+ domain_flush_tlb(&dom->domain);
+ domain_flush_complete(&dom->domain);
+ }
+
+ return address;
+}
+
static unsigned long dma_ops_area_alloc(struct device *dev,
struct dma_ops_domain *dom,
unsigned int pages,
unsigned long align_mask,
- u64 dma_mask,
- unsigned long start)
+ u64 dma_mask)
{
- unsigned long next_bit = dom->next_address % APERTURE_RANGE_SIZE;
- int max_index = dom->aperture_size >> APERTURE_RANGE_SHIFT;
- int i = start >> APERTURE_RANGE_SHIFT;
unsigned long boundary_size, mask;
unsigned long address = -1;
- unsigned long limit;
+ bool first = true;
+ u32 start, i;
- next_bit >>= PAGE_SHIFT;
+ preempt_disable();
mask = dma_get_seg_boundary(dev);
+again:
+ start = this_cpu_read(*dom->next_index);
+
+ /* Sanity check - is it really necessary? */
+ if (unlikely(start > APERTURE_MAX_RANGES)) {
+ start = 0;
+ this_cpu_write(*dom->next_index, 0);
+ }
+
boundary_size = mask + 1 ? ALIGN(mask + 1, PAGE_SIZE) >> PAGE_SHIFT :
1UL << (BITS_PER_LONG - PAGE_SHIFT);
- for (;i < max_index; ++i) {
- unsigned long offset = dom->aperture[i]->offset >> PAGE_SHIFT;
+ for (i = 0; i < APERTURE_MAX_RANGES; ++i) {
+ struct aperture_range *range;
+ int index;
- if (dom->aperture[i]->offset >= dma_mask)
- break;
+ index = (start + i) % APERTURE_MAX_RANGES;
- limit = iommu_device_max_index(APERTURE_RANGE_PAGES, offset,
- dma_mask >> PAGE_SHIFT);
+ range = dom->aperture[index];
- address = iommu_area_alloc(dom->aperture[i]->bitmap,
- limit, next_bit, pages, 0,
- boundary_size, align_mask);
+ if (!range || range->offset >= dma_mask)
+ continue;
+
+ address = dma_ops_aperture_alloc(dom, range, pages,
+ dma_mask, boundary_size,
+ align_mask, first);
if (address != -1) {
- address = dom->aperture[i]->offset +
- (address << PAGE_SHIFT);
- dom->next_address = address + (pages << PAGE_SHIFT);
+ address = range->offset + (address << PAGE_SHIFT);
+ this_cpu_write(*dom->next_index, index);
break;
}
+ }
- next_bit = 0;
+ if (address == -1 && first) {
+ first = false;
+ goto again;
}
+ preempt_enable();
+
return address;
}
@@ -1526,21 +1647,14 @@ static unsigned long dma_ops_alloc_addresses(struct device *dev,
unsigned long align_mask,
u64 dma_mask)
{
- unsigned long address;
-
-#ifdef CONFIG_IOMMU_STRESS
- dom->next_address = 0;
- dom->need_flush = true;
-#endif
+ unsigned long address = -1;
- address = dma_ops_area_alloc(dev, dom, pages, align_mask,
- dma_mask, dom->next_address);
+ while (address == -1) {
+ address = dma_ops_area_alloc(dev, dom, pages,
+ align_mask, dma_mask);
- if (address == -1) {
- dom->next_address = 0;
- address = dma_ops_area_alloc(dev, dom, pages, align_mask,
- dma_mask, 0);
- dom->need_flush = true;
+ if (address == -1 && alloc_new_range(dom, false, GFP_ATOMIC))
+ break;
}
if (unlikely(address == -1))
@@ -1562,6 +1676,7 @@ static void dma_ops_free_addresses(struct dma_ops_domain *dom,
{
unsigned i = address >> APERTURE_RANGE_SHIFT;
struct aperture_range *range = dom->aperture[i];
+ unsigned long flags;
BUG_ON(i >= APERTURE_MAX_RANGES || range == NULL);
@@ -1570,12 +1685,18 @@ static void dma_ops_free_addresses(struct dma_ops_domain *dom,
return;
#endif
- if (address >= dom->next_address)
- dom->need_flush = true;
+ if (amd_iommu_unmap_flush) {
+ domain_flush_tlb(&dom->domain);
+ domain_flush_complete(&dom->domain);
+ }
address = (address % APERTURE_RANGE_SIZE) >> PAGE_SHIFT;
+ spin_lock_irqsave(&range->bitmap_lock, flags);
+ if (address + pages > range->next_bit)
+ range->next_bit = address + pages;
bitmap_clear(range->bitmap, address, pages);
+ spin_unlock_irqrestore(&range->bitmap_lock, flags);
}
@@ -1755,6 +1876,8 @@ static void dma_ops_domain_free(struct dma_ops_domain *dom)
if (!dom)
return;
+ free_percpu(dom->next_index);
+
del_domain_from_list(&dom->domain);
free_pagetable(&dom->domain);
@@ -1769,6 +1892,23 @@ static void dma_ops_domain_free(struct dma_ops_domain *dom)
kfree(dom);
}
+static int dma_ops_domain_alloc_apertures(struct dma_ops_domain *dma_dom,
+ int max_apertures)
+{
+ int ret, i, apertures;
+
+ apertures = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
+ ret = 0;
+
+ for (i = apertures; i < max_apertures; ++i) {
+ ret = alloc_new_range(dma_dom, false, GFP_KERNEL);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
/*
* Allocates a new protection domain usable for the dma_ops functions.
* It also initializes the page table and the address allocator data
@@ -1777,6 +1917,7 @@ static void dma_ops_domain_free(struct dma_ops_domain *dom)
static struct dma_ops_domain *dma_ops_domain_alloc(void)
{
struct dma_ops_domain *dma_dom;
+ int cpu;
dma_dom = kzalloc(sizeof(struct dma_ops_domain), GFP_KERNEL);
if (!dma_dom)
@@ -1785,6 +1926,10 @@ static struct dma_ops_domain *dma_ops_domain_alloc(void)
if (protection_domain_init(&dma_dom->domain))
goto free_dma_dom;
+ dma_dom->next_index = alloc_percpu(u32);
+ if (!dma_dom->next_index)
+ goto free_dma_dom;
+
dma_dom->domain.mode = PAGE_MODE_2_LEVEL;
dma_dom->domain.pt_root = (void *)get_zeroed_page(GFP_KERNEL);
dma_dom->domain.flags = PD_DMA_OPS_MASK;
@@ -1792,8 +1937,6 @@ static struct dma_ops_domain *dma_ops_domain_alloc(void)
if (!dma_dom->domain.pt_root)
goto free_dma_dom;
- dma_dom->need_flush = false;
-
add_domain_to_list(&dma_dom->domain);
if (alloc_new_range(dma_dom, true, GFP_KERNEL))
@@ -1804,8 +1947,9 @@ static struct dma_ops_domain *dma_ops_domain_alloc(void)
* a valid dma-address. So we can use 0 as error value
*/
dma_dom->aperture[0]->bitmap[0] = 1;
- dma_dom->next_address = 0;
+ for_each_possible_cpu(cpu)
+ *per_cpu_ptr(dma_dom->next_index, cpu) = 0;
return dma_dom;
@@ -1905,7 +2049,7 @@ static void do_attach(struct iommu_dev_data *dev_data,
/* Update device table */
set_dte_entry(dev_data->devid, domain, ats);
if (alias != dev_data->devid)
- set_dte_entry(dev_data->devid, domain, ats);
+ set_dte_entry(alias, domain, ats);
device_flush_dte(dev_data);
}
@@ -2328,7 +2472,7 @@ static dma_addr_t dma_ops_domain_map(struct dma_ops_domain *dom,
else if (direction == DMA_BIDIRECTIONAL)
__pte |= IOMMU_PTE_IR | IOMMU_PTE_IW;
- WARN_ON(*pte);
+ WARN_ON_ONCE(*pte);
*pte = __pte;
@@ -2357,7 +2501,7 @@ static void dma_ops_domain_unmap(struct dma_ops_domain *dom,
pte += PM_LEVEL_INDEX(0, address);
- WARN_ON(!*pte);
+ WARN_ON_ONCE(!*pte);
*pte = 0ULL;
}
@@ -2393,26 +2537,11 @@ static dma_addr_t __map_single(struct device *dev,
if (align)
align_mask = (1UL << get_order(size)) - 1;
-retry:
address = dma_ops_alloc_addresses(dev, dma_dom, pages, align_mask,
dma_mask);
- if (unlikely(address == DMA_ERROR_CODE)) {
- /*
- * setting next_address here will let the address
- * allocator only scan the new allocated range in the
- * first run. This is a small optimization.
- */
- dma_dom->next_address = dma_dom->aperture_size;
- if (alloc_new_range(dma_dom, false, GFP_ATOMIC))
- goto out;
-
- /*
- * aperture was successfully enlarged by 128 MB, try
- * allocation again
- */
- goto retry;
- }
+ if (address == DMA_ERROR_CODE)
+ goto out;
start = address;
for (i = 0; i < pages; ++i) {
@@ -2427,11 +2556,10 @@ retry:
ADD_STATS_COUNTER(alloced_io_mem, size);
- if (unlikely(dma_dom->need_flush && !amd_iommu_unmap_flush)) {
- domain_flush_tlb(&dma_dom->domain);
- dma_dom->need_flush = false;
- } else if (unlikely(amd_iommu_np_cache))
+ if (unlikely(amd_iommu_np_cache)) {
domain_flush_pages(&dma_dom->domain, address, size);
+ domain_flush_complete(&dma_dom->domain);
+ }
out:
return address;
@@ -2478,11 +2606,6 @@ static void __unmap_single(struct dma_ops_domain *dma_dom,
SUB_STATS_COUNTER(alloced_io_mem, size);
dma_ops_free_addresses(dma_dom, dma_addr, pages);
-
- if (amd_iommu_unmap_flush || dma_dom->need_flush) {
- domain_flush_pages(&dma_dom->domain, flush_addr, size);
- dma_dom->need_flush = false;
- }
}
/*
@@ -2493,11 +2616,9 @@ static dma_addr_t map_page(struct device *dev, struct page *page,
enum dma_data_direction dir,
struct dma_attrs *attrs)
{
- unsigned long flags;
+ phys_addr_t paddr = page_to_phys(page) + offset;
struct protection_domain *domain;
- dma_addr_t addr;
u64 dma_mask;
- phys_addr_t paddr = page_to_phys(page) + offset;
INC_STATS_COUNTER(cnt_map_single);
@@ -2509,19 +2630,8 @@ static dma_addr_t map_page(struct device *dev, struct page *page,
dma_mask = *dev->dma_mask;
- spin_lock_irqsave(&domain->lock, flags);
-
- addr = __map_single(dev, domain->priv, paddr, size, dir, false,
+ return __map_single(dev, domain->priv, paddr, size, dir, false,
dma_mask);
- if (addr == DMA_ERROR_CODE)
- goto out;
-
- domain_flush_complete(domain);
-
-out:
- spin_unlock_irqrestore(&domain->lock, flags);
-
- return addr;
}
/*
@@ -2530,7 +2640,6 @@ out:
static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir, struct dma_attrs *attrs)
{
- unsigned long flags;
struct protection_domain *domain;
INC_STATS_COUNTER(cnt_unmap_single);
@@ -2539,13 +2648,7 @@ static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
if (IS_ERR(domain))
return;
- spin_lock_irqsave(&domain->lock, flags);
-
__unmap_single(domain->priv, dma_addr, size, dir);
-
- domain_flush_complete(domain);
-
- spin_unlock_irqrestore(&domain->lock, flags);
}
/*
@@ -2556,7 +2659,6 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
- unsigned long flags;
struct protection_domain *domain;
int i;
struct scatterlist *s;
@@ -2572,8 +2674,6 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
dma_mask = *dev->dma_mask;
- spin_lock_irqsave(&domain->lock, flags);
-
for_each_sg(sglist, s, nelems, i) {
paddr = sg_phys(s);
@@ -2588,12 +2688,8 @@ static int map_sg(struct device *dev, struct scatterlist *sglist,
goto unmap;
}
- domain_flush_complete(domain);
-
-out:
- spin_unlock_irqrestore(&domain->lock, flags);
-
return mapped_elems;
+
unmap:
for_each_sg(sglist, s, mapped_elems, i) {
if (s->dma_address)
@@ -2602,9 +2698,7 @@ unmap:
s->dma_address = s->dma_length = 0;
}
- mapped_elems = 0;
-
- goto out;
+ return 0;
}
/*
@@ -2615,7 +2709,6 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction dir,
struct dma_attrs *attrs)
{
- unsigned long flags;
struct protection_domain *domain;
struct scatterlist *s;
int i;
@@ -2626,17 +2719,11 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist,
if (IS_ERR(domain))
return;
- spin_lock_irqsave(&domain->lock, flags);
-
for_each_sg(sglist, s, nelems, i) {
__unmap_single(domain->priv, s->dma_address,
s->dma_length, dir);
s->dma_address = s->dma_length = 0;
}
-
- domain_flush_complete(domain);
-
- spin_unlock_irqrestore(&domain->lock, flags);
}
/*
@@ -2648,7 +2735,6 @@ static void *alloc_coherent(struct device *dev, size_t size,
{
u64 dma_mask = dev->coherent_dma_mask;
struct protection_domain *domain;
- unsigned long flags;
struct page *page;
INC_STATS_COUNTER(cnt_alloc_coherent);
@@ -2680,19 +2766,11 @@ static void *alloc_coherent(struct device *dev, size_t size,
if (!dma_mask)
dma_mask = *dev->dma_mask;
- spin_lock_irqsave(&domain->lock, flags);
-
*dma_addr = __map_single(dev, domain->priv, page_to_phys(page),
size, DMA_BIDIRECTIONAL, true, dma_mask);
- if (*dma_addr == DMA_ERROR_CODE) {
- spin_unlock_irqrestore(&domain->lock, flags);
+ if (*dma_addr == DMA_ERROR_CODE)
goto out_free;
- }
-
- domain_flush_complete(domain);
-
- spin_unlock_irqrestore(&domain->lock, flags);
return page_address(page);
@@ -2712,7 +2790,6 @@ static void free_coherent(struct device *dev, size_t size,
struct dma_attrs *attrs)
{
struct protection_domain *domain;
- unsigned long flags;
struct page *page;
INC_STATS_COUNTER(cnt_free_coherent);
@@ -2724,14 +2801,8 @@ static void free_coherent(struct device *dev, size_t size,
if (IS_ERR(domain))
goto free_mem;
- spin_lock_irqsave(&domain->lock, flags);
-
__unmap_single(domain->priv, dma_addr, size, DMA_BIDIRECTIONAL);
- domain_flush_complete(domain);
-
- spin_unlock_irqrestore(&domain->lock, flags);
-
free_mem:
if (!dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT))
__free_pages(page, get_order(size));
@@ -2746,14 +2817,43 @@ static int amd_iommu_dma_supported(struct device *dev, u64 mask)
return check_device(dev);
}
+static int set_dma_mask(struct device *dev, u64 mask)
+{
+ struct protection_domain *domain;
+ int max_apertures = 1;
+
+ domain = get_domain(dev);
+ if (IS_ERR(domain))
+ return PTR_ERR(domain);
+
+ if (mask == DMA_BIT_MASK(64))
+ max_apertures = 8;
+ else if (mask > DMA_BIT_MASK(32))
+ max_apertures = 4;
+
+ /*
+ * To prevent lock contention it doesn't make sense to allocate more
+ * apertures than online cpus
+ */
+ if (max_apertures > num_online_cpus())
+ max_apertures = num_online_cpus();
+
+ if (dma_ops_domain_alloc_apertures(domain->priv, max_apertures))
+ dev_err(dev, "Can't allocate %d iommu apertures\n",
+ max_apertures);
+
+ return 0;
+}
+
static struct dma_map_ops amd_iommu_dma_ops = {
- .alloc = alloc_coherent,
- .free = free_coherent,
- .map_page = map_page,
- .unmap_page = unmap_page,
- .map_sg = map_sg,
- .unmap_sg = unmap_sg,
- .dma_supported = amd_iommu_dma_supported,
+ .alloc = alloc_coherent,
+ .free = free_coherent,
+ .map_page = map_page,
+ .unmap_page = unmap_page,
+ .map_sg = map_sg,
+ .unmap_sg = unmap_sg,
+ .dma_supported = amd_iommu_dma_supported,
+ .set_dma_mask = set_dma_mask,
};
int __init amd_iommu_init_api(void)
@@ -3757,11 +3857,9 @@ static struct irq_domain *get_irq_domain(struct irq_alloc_info *info)
case X86_IRQ_ALLOC_TYPE_MSI:
case X86_IRQ_ALLOC_TYPE_MSIX:
devid = get_device_id(&info->msi_dev->dev);
- if (devid >= 0) {
- iommu = amd_iommu_rlookup_table[devid];
- if (iommu)
- return iommu->msi_domain;
- }
+ iommu = amd_iommu_rlookup_table[devid];
+ if (iommu)
+ return iommu->msi_domain;
break;
default:
break;