Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
target/arm/mte_helper.c | 96 +++++++++++++++++++++++++++++++++++++----
1 file changed, 87 insertions(+), 9 deletions(-)
diff --git a/target/arm/mte_helper.c b/target/arm/mte_helper.c
index ad2902472d..3abed62018 100644
--- a/target/arm/mte_helper.c
+++ b/target/arm/mte_helper.c
@@ -53,19 +53,19 @@ static uint64_t strip_tbi(CPUARMState *env, uint64_t ptr)
static uint8_t *allocation_tag_mem(CPUARMState *env, uint64_t ptr,
bool write, uintptr_t ra)
{
-#ifdef CONFIG_USER_ONLY
ARMCPU *cpu = arm_env_get_cpu(env);
+ CPUState *cs = CPU(cpu);
uint64_t clean_ptr = strip_tbi(env, ptr);
uint8_t *tags;
uintptr_t index;
- int flags;
- flags = page_get_flags(clean_ptr);
+#ifdef CONFIG_USER_ONLY
+ int flags = page_get_flags(clean_ptr);
if (!(flags & PAGE_VALID) || !(flags & (write ? PAGE_WRITE : PAGE_READ))) {
/* SIGSEGV */
env->exception.vaddress = ptr;
- cpu_restore_state(CPU(cpu), ra, true);
+ cpu_restore_state(cs, ra, true);
raise_exception(env, EXCP_DATA_ABORT, 0, 1);
}
@@ -82,16 +82,94 @@ static uint8_t *allocation_tag_mem(CPUARMState *env,
uint64_t ptr,
if (tags == NULL) {
size_t alloc_size = TARGET_PAGE_SIZE >> (LOG2_TAG_GRANULE + 1);
tags = page_alloc_target_data(clean_ptr, alloc_size);
- assert(tags != NULL);
+ }
+#else
+ int mmu_idx;
+ AddressSpace *as;
+ CPUTLBEntry *te;
+ CPUIOTLBEntry *iotlbentry;
+ MemoryRegionSection *section;
+ MemoryRegion *mr;
+ FlatView *fv;
+ hwaddr physaddr, tag_physaddr, tag_len, xlat;
+
+ /*
+ * Find the TLB entry for this access.
+ * As a side effect, this also raises an exception for invalid access.
+ */
+ mmu_idx = cpu_mmu_index(env, false);
+ index = tlb_index(env, mmu_idx, clean_ptr);
+ te = tlb_entry(env, mmu_idx, clean_ptr);
+ if (!tlb_hit(write ? tlb_addr_write(te) : te->addr_read, clean_ptr)) {
+ /* ??? Expose VICTIM_TLB_HIT from accel/tcg/cputlb.c. */
+ tlb_fill(cs, ptr, 16, write ? MMU_DATA_STORE : MMU_DATA_LOAD,
+ mmu_idx, ra);
+ index = tlb_index(env, mmu_idx, clean_ptr);
+ te = tlb_entry(env, mmu_idx, clean_ptr);
}
+ /* If the virtual page MemAttr != Tagged, nothing to do. */
+ iotlbentry = &env->iotlb[mmu_idx][index];
+ if (!iotlbentry->attrs.target_tlb_bit1) {
+ return NULL;
+ }
+
+ /* If the board did not allocate tag memory, nothing to do. */
+ as = cpu_get_address_space(cs, ARMASIdx_TAG);
+ if (!as) {
+ return NULL;
+ }
+
+ /* Find the physical address for the virtual access. */
+ section = iotlb_to_section(cs, iotlbentry->addr, iotlbentry->attrs);
+ physaddr = ((iotlbentry->addr & TARGET_PAGE_MASK) + clean_ptr
+ + section->offset_within_address_space
+ - section->offset_within_region);
+
+ /* Convert to the physical address in tag space. */
+ tag_physaddr = physaddr >> (LOG2_TAG_GRANULE + 1);
+ tag_len = TARGET_PAGE_SIZE >> (LOG2_TAG_GRANULE + 1);
+
+ /*
+ * Find the tag physical address within the tag address space.
+ *
+ * ??? Create a new mmu_idx to cache the rest of this.
+ *
+ * ??? If we were assured of exactly one block of normal ram,
+ * and thus exactly one block of tag ram, then we could validate
+ * section->mr as ram, use the section offset vs cpu->tag_memory,
+ * and finish with memory_region_get_ram_ptr.
+ */
+ rcu_read_lock();
+ fv = address_space_to_flatview(as);
+ mr = flatview_translate(fv, tag_physaddr, &xlat, &tag_len,
+ write, MEMTXATTRS_UNSPECIFIED);
+ if (!memory_access_is_direct(mr, write)) {
+ /*
+ * This would seem to imply that the guest has marked a
+ * virtual page as Tagged when the physical page is not RAM.
+ * Should this raise some sort of bus error?
+ */
+ rcu_read_unlock();
+ qemu_log_mask(LOG_GUEST_ERROR, "Tagged virtual page 0x%" PRIx64
+ " maps to physical page 0x%" PRIx64 " without RAM\n",
+ clean_ptr, physaddr);
+ return NULL;
+ }
+ rcu_read_unlock();
+
+ /* The board should have created tag ram sized correctly. */
+ assert(tag_len == TARGET_PAGE_SIZE >> (LOG2_TAG_GRANULE + 1));
+
+ /* FIXME: Mark the tag page dirty for migration. */
+
+ tags = qemu_map_ram_ptr(mr->ram_block, xlat);
+#endif
+
+ assert(tags != NULL);
index = extract32(clean_ptr, LOG2_TAG_GRANULE + 1,
TARGET_PAGE_BITS - LOG2_TAG_GRANULE - 1);
return tags + index;
-#else
- /* Tag storage not implemented. */
- return NULL;
-#endif
}
static int get_allocation_tag(CPUARMState *env, uint64_t ptr, uintptr_t ra)
--
2.17.2
