@@ -298,6 +298,11 @@ bool iommu_dma_memory_valid(DMAContext *dma, dma_addr_t addr, dma_addr_t len,
plen = len;
}
+ if (!address_space_access_valid(dma->as, paddr, len,
+ dir == DMA_DIRECTION_FROM_DEVICE)) {
+ return false;
+ }
+
len -= plen;
addr += plen;
}
@@ -2064,6 +2064,27 @@ static void cpu_notify_map_clients(void)
}
}
+bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_write)
+{
+ MemoryRegionSection *section;
+ hwaddr l, xlat;
+
+ while (len > 0) {
+ l = len;
+ section = address_space_translate(as, addr, &xlat, &l, is_write);
+ if (!memory_access_is_direct(section->mr, is_write)) {
+ l = memory_access_size(l, addr);
+ if (!memory_region_access_valid(section->mr, xlat, l, is_write)) {
+ return false;
+ }
+ }
+
+ len -= l;
+ addr += l;
+ }
+ return true;
+}
+
/* Map a physical memory region into a host virtual address.
* May map a subset of the requested range, given by and returned in *plen.
* May return NULL if resources needed to perform the mapping are exhausted.
@@ -866,6 +866,21 @@ MemoryRegionSection *address_space_translate(AddressSpace *as, hwaddr addr,
hwaddr *xlat, hwaddr *len,
bool is_write);
+/* address_space_access_valid: check for validity of accessing an address
+ * space range
+ *
+ * Check whether memory is assigned to the given address space range.
+ *
+ * For now, addr and len should be aligned to a page size. This limitation
+ * will be lifted in the future.
+ *
+ * @as: #AddressSpace to be accessed
+ * @addr: address within that address space
+ * @len: length of the area to be checked
+ * @is_write: indicates the transfer direction
+ */
+bool address_space_access_valid(AddressSpace *as, hwaddr addr, int len, bool is_write);
+
/* address_space_map: map a physical memory region into a host virtual address
*
* May map a subset of the requested range, given by and returned in @plen.
@@ -113,7 +113,8 @@ static inline bool dma_memory_valid(DMAContext *dma,
DMADirection dir)
{
if (!dma_has_iommu(dma)) {
- return true;
+ return address_space_access_valid(dma->as, addr, len,
+ dir == DMA_DIRECTION_FROM_DEVICE);
} else {
return iommu_dma_memory_valid(dma, addr, len, dir);
}
The old-style IOMMU lets you check whether an access is valid in a given DMAContext. There is no equivalent for AddressSpace in the memory API, but we can implement it easily. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- dma-helpers.c | 5 +++++ exec.c | 21 +++++++++++++++++++++ include/exec/memory.h | 15 +++++++++++++++ include/sysemu/dma.h | 3 ++- 4 files changed, 43 insertions(+), 1 deletion(-)