Introduce IOMMUTLBEntryUnaligned which has a @len field to specify the
iotlb size to abstract a generic iotlb entry: aligned (original
IOMMUTLBEntry) and unaligned entry. flatview_do_translate() now
returns a magic value in @page_mask_out if no IOMMU translation is
needed. Then, address_space_get_iotbl_entry() can accordingly return a
page-aligned iotlb entry or the whole memory region section where the
iova resides as a large iotlb entry.
Signed-off-by: Chao Gao <chao....@intel.com>
---
hw/virtio/vhost.c | 6 +++---
include/exec/memory.h | 16 ++++++++++++++--
softmmu/physmem.c | 37 +++++++++++++++++++++++++++++--------
3 files changed, 46 insertions(+), 13 deletions(-)
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index e8f85a5d2d..6745caa129 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1010,7 +1010,7 @@ static int vhost_memory_region_lookup(struct vhost_dev
*hdev,
int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write)
{
- IOMMUTLBEntry iotlb;
+ IOMMUTLBEntryUnaligned iotlb;
uint64_t uaddr, len;
int ret = -EFAULT;
@@ -1031,8 +1031,8 @@ int vhost_device_iotlb_miss(struct vhost_dev *dev,
uint64_t iova, int write)
goto out;
}
- len = MIN(iotlb.addr_mask + 1, len);
- iova = iova & ~iotlb.addr_mask;
+ len = MIN(iotlb.len, len);
+ iova = iotlb.iova;
ret = vhost_backend_update_device_iotlb(dev, iova, uaddr,
len, iotlb.perm);
diff --git a/include/exec/memory.h b/include/exec/memory.h
index c3d417d317..3f04e8fe88 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -94,6 +94,7 @@ struct MemoryRegionSection {
};
typedef struct IOMMUTLBEntry IOMMUTLBEntry;
+typedef struct IOMMUTLBEntryUnaligned IOMMUTLBEntryUnaligned;
/* See address_space_translate: bit 0 is read, bit 1 is write. */
typedef enum {
@@ -113,6 +114,15 @@ struct IOMMUTLBEntry {
IOMMUAccessFlags perm;
};
+/* IOMMUTLBEntryUnaligned may be not page-aligned */
+struct IOMMUTLBEntryUnaligned {
+ AddressSpace *target_as;
+ hwaddr iova;
+ hwaddr translated_addr;
+ hwaddr len;
+ IOMMUAccessFlags perm;
+};
+
/*
* Bitmap for different IOMMUNotifier capabilities. Each notifier can
* register with one or multiple IOMMU Notifier capability bit(s).
@@ -2653,8 +2663,10 @@ void address_space_cache_destroy(MemoryRegionCache
*cache);
/* address_space_get_iotlb_entry: translate an address into an IOTLB
* entry. Should be called from an RCU critical section.
*/
-IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
- bool is_write, MemTxAttrs attrs);
+IOMMUTLBEntryUnaligned address_space_get_iotlb_entry(AddressSpace *as,
+ hwaddr addr,
+ bool is_write,
+ MemTxAttrs attrs);
/* address_space_translate: translate an address range into an address space
* into a MemoryRegion and an address range into that section. Should be
diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 3c1912a1a0..469963f754 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -143,6 +143,8 @@ typedef struct subpage_t {
#define PHYS_SECTION_UNASSIGNED 0
+#define PAGE_MASK_NOT_BEHIND_IOMMU ((hwaddr)-1)
+
static void io_mem_init(void);
static void memory_map_init(void);
static void tcg_log_global_after_sync(MemoryListener *listener);
@@ -470,7 +472,9 @@ unassigned:
* @page_mask_out: page mask for the translated address. This
* should only be meaningful for IOMMU translated
* addresses, since there may be huge pages that this bit
- * would tell. It can be @NULL if we don't care about it.
+ * would tell. If the returned memory region section isn't
+ * behind an IOMMU, PAGE_MASK_NOT_BEHIND_IOMMU is return.
+ * It can be @NULL if we don't care about it.
* @is_write: whether the translation operation is for write
* @is_mmio: whether this can be MMIO, set true if it can
* @target_as: the address space targeted by the IOMMU
@@ -508,16 +512,18 @@ static MemoryRegionSection flatview_do_translate(FlatView
*fv,
target_as, attrs);
}
if (page_mask_out) {
- /* Not behind an IOMMU, use default page size. */
- *page_mask_out = ~TARGET_PAGE_MASK;
+ /* return a magic value if not behind an IOMMU */
+ *page_mask_out = PAGE_MASK_NOT_BEHIND_IOMMU;
}
return *section;
}
/* Called from RCU critical section */
-IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace *as, hwaddr addr,
- bool is_write, MemTxAttrs attrs)
+IOMMUTLBEntryUnaligned address_space_get_iotlb_entry(AddressSpace *as,
+ hwaddr addr,
+ bool is_write,
+ MemTxAttrs attrs)
{
MemoryRegionSection section;
hwaddr xlat, page_mask;
@@ -535,21 +541,36 @@ IOMMUTLBEntry address_space_get_iotlb_entry(AddressSpace
*as, hwaddr addr,
goto iotlb_fail;
}
+ /*
+ * If the section isn't behind an IOMMU, return the whole section as an
+ * IOMMU TLB entry.
+ */
+ if (page_mask == PAGE_MASK_NOT_BEHIND_IOMMU) {
+ return (IOMMUTLBEntryUnaligned) {
+ .target_as = as,
+ .iova = section.offset_within_address_space,
+ .translated_addr = section.offset_within_address_space,
+ .len = section.size,
+ /* IOTLBs are for DMAs, and DMA only allows on RAMs. */
+ .perm = IOMMU_RW,
+ };
+ }
+
/* Convert memory region offset into address space offset */
xlat += section.offset_within_address_space -
section.offset_within_region;
- return (IOMMUTLBEntry) {
+ return (IOMMUTLBEntryUnaligned) {
.target_as = as,
.iova = addr & ~page_mask,
.translated_addr = xlat & ~page_mask,
- .addr_mask = page_mask,
+ .len = page_mask + 1,
/* IOTLBs are for DMAs, and DMA only allows on RAMs. */
.perm = IOMMU_RW,
};
iotlb_fail:
- return (IOMMUTLBEntry) {0};
+ return (IOMMUTLBEntryUnaligned) {0};
}
/* Called from RCU critical section */
--
2.25.1
