The io_mem_watch MemoryRegion's read and write callbacks pass the
accesses through to an underlying address space. Now that that
might be something other than address_space_memory, we need to
pass the correct AddressSpace in via the opaque pointer. That
means we need to have one io_mem_watch MemoryRegion per address
space, rather than sharing one between all address spaces.
This should also fix gdbstub watchpoints in x86 SMRAM, which would
previously not have worked correctly.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
exec.c | 40 +++++++++++++++++++++++-----------------
include/exec/memory.h | 2 ++
2 files changed, 25 insertions(+), 17 deletions(-)
diff --git a/exec.c b/exec.c
index bc6ab8a..9998fa0 100644
--- a/exec.c
+++ b/exec.c
@@ -163,8 +163,6 @@ static void io_mem_init(void);
static void memory_map_init(void);
static void tcg_commit(MemoryListener *listener);
-static MemoryRegion io_mem_watch;
-
/**
* CPUAddressSpace: all the information a CPU needs about an AddressSpace
* @cpu: the CPU whose AddressSpace this is
@@ -334,12 +332,6 @@ static MemoryRegionSection *phys_page_find(PhysPageEntry
lp, hwaddr addr,
}
}
-bool memory_region_is_unassigned(MemoryRegion *mr)
-{
- return mr != &io_mem_rom && mr != &io_mem_notdirty && !mr->rom_device
- && mr != &io_mem_watch;
-}
-
/* Called from RCU critical section */
static MemoryRegionSection *address_space_lookup_region(AddressSpaceDispatch
*d,
hwaddr addr,
@@ -2045,17 +2037,18 @@ static MemTxResult watch_mem_read(void *opaque, hwaddr
addr, uint64_t *pdata,
{
MemTxResult res;
uint64_t data;
+ AddressSpace *as = opaque;
check_watchpoint(addr & ~TARGET_PAGE_MASK, size, attrs, BP_MEM_READ);
switch (size) {
case 1:
- data = address_space_ldub(&address_space_memory, addr, attrs, &res);
+ data = address_space_ldub(as, addr, attrs, &res);
break;
case 2:
- data = address_space_lduw(&address_space_memory, addr, attrs, &res);
+ data = address_space_lduw(as, addr, attrs, &res);
break;
case 4:
- data = address_space_ldl(&address_space_memory, addr, attrs, &res);
+ data = address_space_ldl(as, addr, attrs, &res);
break;
default: abort();
}
@@ -2068,17 +2061,18 @@ static MemTxResult watch_mem_write(void *opaque, hwaddr
addr,
MemTxAttrs attrs)
{
MemTxResult res;
+ AddressSpace *as = opaque;
check_watchpoint(addr & ~TARGET_PAGE_MASK, size, attrs, BP_MEM_WRITE);
switch (size) {
case 1:
- address_space_stb(&address_space_memory, addr, val, attrs, &res);
+ address_space_stb(as, addr, val, attrs, &res);
break;
case 2:
- address_space_stw(&address_space_memory, addr, val, attrs, &res);
+ address_space_stw(as, addr, val, attrs, &res);
break;
case 4:
- address_space_stl(&address_space_memory, addr, val, attrs, &res);
+ address_space_stl(as, addr, val, attrs, &res);
break;
default: abort();
}
@@ -2091,6 +2085,15 @@ static const MemoryRegionOps watch_mem_ops = {
.endianness = DEVICE_NATIVE_ENDIAN,
};
+bool memory_region_is_unassigned(MemoryRegion *mr)
+{
+ /* Checking the ops pointer of the MemoryRegion is strictly
+ * speaking looking at private information of the MemoryRegion :-(
+ */
+ return mr != &io_mem_rom && mr != &io_mem_notdirty && !mr->rom_device
+ && mr->ops != &watch_mem_ops;
+}
+
static MemTxResult subpage_read(void *opaque, hwaddr addr, uint64_t *data,
unsigned len, MemTxAttrs attrs)
{
@@ -2251,8 +2254,6 @@ static void io_mem_init(void)
NULL, UINT64_MAX);
memory_region_init_io(&io_mem_notdirty, NULL, ¬dirty_mem_ops, NULL,
NULL, UINT64_MAX);
- memory_region_init_io(&io_mem_watch, NULL, &watch_mem_ops, NULL,
- NULL, UINT64_MAX);
}
static void mem_begin(MemoryListener *listener)
@@ -2267,7 +2268,7 @@ static void mem_begin(MemoryListener *listener)
assert(n == PHYS_SECTION_NOTDIRTY);
n = dummy_section(&d->map, as, &io_mem_rom);
assert(n == PHYS_SECTION_ROM);
- n = dummy_section(&d->map, as, &io_mem_watch);
+ n = dummy_section(&d->map, as, as->io_mem_watch);
assert(n == PHYS_SECTION_WATCH);
d->phys_map = (PhysPageEntry) { .ptr = PHYS_MAP_NODE_NIL, .skip = 1 };
@@ -2315,6 +2316,10 @@ static void tcg_commit(MemoryListener *listener)
void address_space_init_dispatch(AddressSpace *as)
{
+ as->io_mem_watch = g_new0(MemoryRegion, 1);
+ memory_region_init_io(as->io_mem_watch, NULL, &watch_mem_ops, as,
+ NULL, UINT64_MAX);
+
as->dispatch = NULL;
as->dispatch_listener = (MemoryListener) {
.begin = mem_begin,
@@ -2339,6 +2344,7 @@ void address_space_destroy_dispatch(AddressSpace *as)
if (d) {
call_rcu(d, address_space_dispatch_free, rcu);
}
+ memory_region_unref(as->io_mem_watch);
}
static void memory_map_init(void)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 0f07159..e5d98f8 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -246,6 +246,8 @@ struct AddressSpace {
struct AddressSpaceDispatch *next_dispatch;
MemoryListener dispatch_listener;
+ MemoryRegion *io_mem_watch;
+
QTAILQ_ENTRY(AddressSpace) address_spaces_link;
};
--
1.9.1
