Signed-off-by: Liu Ping Fan <pingf...@linux.vnet.ibm.com>
---
cpus.c | 3 ++
exec.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
qemu-thread.h | 8 +++++++
vl.c | 1 +
4 files changed, 70 insertions(+), 0 deletions(-)
diff --git a/cpus.c b/cpus.c
index 191cbf5..e67d80f 100644
--- a/cpus.c
+++ b/cpus.c
@@ -733,6 +733,7 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
qemu_mutex_lock(&qemu_global_mutex);
qemu_thread_get_self(cpu->thread);
+ qemu_thread_init_context();
env->thread_id = qemu_get_thread_id();
cpu_single_env = env;
@@ -774,6 +775,7 @@ static void *qemu_dummy_cpu_thread_fn(void *arg)
qemu_mutex_lock_iothread();
qemu_thread_get_self(cpu->thread);
+ qemu_thread_init_context();
env->thread_id = qemu_get_thread_id();
sigemptyset(&waitset);
@@ -813,6 +815,7 @@ static void *qemu_tcg_cpu_thread_fn(void *arg)
qemu_tcg_init_cpu_signals();
qemu_thread_get_self(cpu->thread);
+ qemu_thread_init_context();
/* signal CPU creation */
qemu_mutex_lock(&qemu_global_mutex);
diff --git a/exec.c b/exec.c
index 46da08c..ea672c6 100644
--- a/exec.c
+++ b/exec.c
@@ -3449,6 +3449,49 @@ static bool
address_space_section_lookup_ref(AddressSpace *as,
return safe_ref;
}
+typedef struct ThreadContext {
+ DispatchType dispatch_type;
+ unsigned int mmio_req_pending;
+} ThreadContext;
+
+static __thread ThreadContext *thread_context;
+
+void qemu_thread_init_context(void)
+{
+ thread_context = g_new(ThreadContext, 1);
+ thread_context->dispatch_type = DISPATCH_INIT;
+ thread_context->mmio_req_pending = 0;
+}
+
+void qemu_thread_set_dispatch_type(DispatchType type)
+{
+ thread_context->dispatch_type = type;
+}
+
+void qemu_thread_reset_dispatch_type(void)
+{
+ thread_context->dispatch_type = DISPATCH_INIT;
+}
+
+static bool address_space_inc_req_pending(void)
+{
+ bool nested = false;
+
+ /* currently, only mmio out of big lock, and need this to avoid dead lock
*/
+ if (thread_context->dispatch_type == DISPATCH_MMIO) {
+ nested = ++thread_context->mmio_req_pending > 1 ? true : false;
+ }
+
+ return nested;
+}
+
+static void address_space_dec_req_pending(void)
+{
+ if (thread_context->dispatch_type == DISPATCH_MMIO) {
+ thread_context->mmio_req_pending--;
+ }
+}
+
void address_space_rw(AddressSpace *as, target_phys_addr_t addr, uint8_t *buf,
int len, bool is_write)
{
@@ -3459,6 +3502,7 @@ void address_space_rw(AddressSpace *as,
target_phys_addr_t addr, uint8_t *buf,
target_phys_addr_t page;
bool safe_ref = false;
MemoryRegionSection *section, obj_mrs;
+ bool nested_dma = false;
while (len > 0) {
page = addr & TARGET_PAGE_MASK;
@@ -3485,10 +3529,17 @@ void address_space_rw(AddressSpace *as,
target_phys_addr_t addr, uint8_t *buf,
memory_region_section_lookup_ref(d, page, &obj_mrs);
}
section = &obj_mrs;
+ nested_dma = address_space_inc_req_pending();
if (is_write) {
if (!memory_region_is_ram(section->mr)) {
target_phys_addr_t addr1;
+
+ /* To fix, will filter iommu case */
+ if (nested_dma) {
+ fprintf(stderr, "can not support nested DMA");
+ abort();
+ }
addr1 = memory_region_section_addr(section, addr);
/* XXX: could force cpu_single_env to NULL to avoid
potential bugs */
@@ -3522,6 +3573,12 @@ void address_space_rw(AddressSpace *as,
target_phys_addr_t addr, uint8_t *buf,
if (!(memory_region_is_ram(section->mr) ||
memory_region_is_romd(section->mr))) {
target_phys_addr_t addr1;
+
+ /* To fix, will filter iommu case */
+ if (nested_dma) {
+ fprintf(stderr, "can not support nested DMA");
+ abort();
+ }
/* I/O case */
addr1 = memory_region_section_addr(section, addr);
if (l >= 4 && ((addr1 & 3) == 0)) {
@@ -3549,6 +3606,7 @@ void address_space_rw(AddressSpace *as,
target_phys_addr_t addr, uint8_t *buf,
qemu_put_ram_ptr(ptr);
}
}
+ address_space_dec_req_pending();
memory_region_section_unref(&obj_mrs);
len -= l;
buf += l;
diff --git a/qemu-thread.h b/qemu-thread.h
index 05fdaaf..bb9535e 100644
--- a/qemu-thread.h
+++ b/qemu-thread.h
@@ -7,6 +7,11 @@
typedef struct QemuMutex QemuMutex;
typedef struct QemuCond QemuCond;
typedef struct QemuThread QemuThread;
+typedef enum {
+ DISPATCH_INIT = 0,
+ DISPATCH_MMIO,
+ DISPATCH_IO,
+} DispatchType;
#ifdef _WIN32
#include "qemu-thread-win32.h"
@@ -46,4 +51,7 @@ void qemu_thread_get_self(QemuThread *thread);
bool qemu_thread_is_self(QemuThread *thread);
void qemu_thread_exit(void *retval);
+void qemu_thread_init_context(void);
+void qemu_thread_set_dispatch_type(DispatchType type);
+void qemu_thread_reset_dispatch_type(void);
#endif
diff --git a/vl.c b/vl.c
index ee3c43a..be8d825 100644
--- a/vl.c
+++ b/vl.c
@@ -3439,6 +3439,7 @@ int main(int argc, char **argv, char **envp)
add_device_config(DEV_VIRTCON, "vc:80Cx24C");
}
+ qemu_thread_init_context();
socket_init();
if (qemu_opts_foreach(qemu_find_opts("chardev"), chardev_init_func, NULL,
1) != 0)
--
1.7.4.4
