[PATCH 04/11] exec: Add address_space_read and address_space_write debug helpers.

Ashish Kalra
2020-11-16T18:50:51Z

From: Ashish Kalra <ashish.kalra@amd.com>

Add new address_space_read and address_space_write debug helper
interfaces which can be invoked by vendor specific guest memory
debug assist/hooks to do guest RAM memory accesses using the
added MemoryRegion callbacks.

Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
---
include/exec/memory.h | 10 +++++
softmmu/physmem.c | 88 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 98 insertions(+)

diff --git a/include/exec/memory.h b/include/exec/memory.h
index 2fb4193358..74f2dcec00 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -2432,6 +2432,16 @@ typedef struct MemoryDebugOps {

void address_space_set_debug_ops(const MemoryDebugOps *ops);

+MemTxResult address_space_write_rom_debug(AddressSpace *as,
+ hwaddr addr,
+ MemTxAttrs attrs,
+ const void *ptr,
+ hwaddr len);
+
+MemTxResult address_space_read_debug(AddressSpace *as, hwaddr addr,
+ MemTxAttrs attrs, void *buf,
+ hwaddr len);
+
static inline bool memory_access_is_direct(MemoryRegion *mr, bool is_write)
{
if (is_write) {
diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 057d6d4ce1..2c08624ca8 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -3266,6 +3266,94 @@ void cpu_physical_memory_unmap(void *buffer, hwaddr len,
#define RCU_READ_UNLOCK(...) rcu_read_unlock()
#include "memory_ldst.c.inc"

+MemTxResult address_space_read_debug(AddressSpace *as, hwaddr addr,
+ MemTxAttrs attrs, void *ptr,
+ hwaddr len)
+{
+ uint64_t val;
+ MemoryRegion *mr;
+ hwaddr l = len;
+ hwaddr addr1;
+ MemTxResult result = MEMTX_OK;
+ bool release_lock = false;
+ uint8_t *buf = ptr;
+ uint8_t *ram_ptr;
+
+ for (;;) {
+ RCU_READ_LOCK_GUARD();
+ mr = address_space_translate(as, addr, &addr1, &l, false, attrs);
+ if (!memory_access_is_direct(mr, false)) {
+ /* I/O case */
+ release_lock |= prepare_mmio_access(mr);
+ l = memory_access_size(mr, l, addr1);
+ result |= memory_region_dispatch_read(mr, addr1, &val,
+ size_memop(l), attrs);
+ stn_he_p(buf, l, val);
+ } else {
+ /* RAM case */
+ fuzz_dma_read_cb(addr, l, mr, false);
+ ram_ptr = qemu_ram_ptr_length(mr->ram_block, addr1, &l, false);
+ if (attrs.debug && mr->ram_debug_ops) {
+ mr->ram_debug_ops->read(buf, ram_ptr, l, attrs);
+ } else {
+ memcpy(buf, ram_ptr, l);
+ }
+ result = MEMTX_OK;
+ }
+ if (release_lock) {
+ qemu_mutex_unlock_iothread();
+ release_lock = false;
+ }
+
+ len -= l;
+ buf += l;
+ addr += l;
+
+ if (!len) {
+ break;
+ }
+ l = len;
+ }
+ return result;
+}
+
+inline MemTxResult address_space_write_rom_debug(AddressSpace *as,
+ hwaddr addr,
+ MemTxAttrs attrs,
+ const void *ptr,
+ hwaddr len)
+{
+ hwaddr l;
+ uint8_t *ram_ptr;
+ hwaddr addr1;
+ MemoryRegion *mr;
+ const uint8_t *buf = ptr;
+
+ RCU_READ_LOCK_GUARD();
+ while (len > 0) {
+ l = len;
+ mr = address_space_translate(as, addr, &addr1, &l, true, attrs);
+
+ if (!(memory_region_is_ram(mr) ||
+ memory_region_is_romd(mr))) {
+ l = memory_access_size(mr, l, addr1);
+ } else {
+ /* ROM/RAM case */
+ ram_ptr = qemu_map_ram_ptr(mr->ram_block, addr1);
+ if (attrs.debug && mr->ram_debug_ops) {
+ mr->ram_debug_ops->write(ram_ptr, buf, l, attrs);
+ } else {
+ memcpy(ram_ptr, buf, l);
+ }
+ invalidate_and_set_dirty(mr, addr1, l);
+ }
+ len -= l;
+ buf += l;
+ addr += l;
+ }
+ return MEMTX_OK;
+}
+
int64_t address_space_cache_init(MemoryRegionCache *cache,
AddressSpace *as,
hwaddr addr,
--
2.17.1