Introducing shmem

nx/include/switch.h

@@ -15,6 +15,7 @@ extern "C" {
 #include <switch/os.h>
 
 #include <switch/kernel/tmem.h>
+#include <switch/kernel/shmem.h>
 #include <switch/kernel/mutex.h>
 #include <switch/kernel/thread.h>
 #include <switch/kernel/virtmem.h>

nx/include/switch/kernel/shmem.h

@@ -0,0 +1,15 @@
+typedef struct {
+    Handle      MemHandle;
+    size_t      Size;
+    Permission  Perm;
+    void*       MappedAddr;
+} SharedMemory;
+
+Result shmemCreate(SharedMemory* s, size_t size, Permission local_perm, Permission remote_perm);
+void shmemLoadRemote(SharedMemory* t, Handle handle, size_t size, Permission perm);
+
+Result shmemMap(SharedMemory* t);
+Result shmemUnmap(SharedMemory* t);
+void*  shmemGetAddr(SharedMemory* t);
+
+Result shmemClose(SharedMemory* t);

nx/include/switch/svc.h

@@ -30,14 +30,7 @@ typedef struct {
 } MemInfo;
 
 typedef struct {
-	u64 X0;
-	u64 X1;
-	u64 X2;
-	u64 X3;
-	u64 X4;
-	u64 X5;
-	u64 X6;
-	u64 X7;
+    u64 X[8];
 } __attribute__((packed)) SecmonArgs;
 
 Result svcSetHeapSize(void** out_addr, u64 size);
@@ -51,6 +44,8 @@ void NORETURN svcExitThread();
 Result svcSleepThread(u64 nano);
 Result svcClearEvent(Handle handle);
 Result svcCloseHandle(Handle handle);
+Result svcMapSharedMemory(Handle handle, void* addr, size_t size, u32 perm);
+Result svcUnmapSharedMemory(Handle handle, void* addr, size_t size);
 Result svcCreateTransferMemory(Handle* out, void* addr, size_t size, u32 perm);
 Result svcWaitSynchronization(s32* index, const Handle* handles, s32 handleCount, u64 timeout);
 Result svcArbitrateLock(u32 wait_tag, u32* tag_location, u32 self_tag);
@@ -62,6 +57,7 @@ Result svcGetInfo(u64* out, u64 id0, Handle handle, u64 id1);
 Result svcCreateSession(Handle *server_handle, Handle *client_handle, u32 unk0, u64 unk1);//unk* are normally 0?
 Result svcAcceptSession(Handle *session_handle, Handle port_handle);
 Result svcReplyAndReceive(s32* index, const Handle* handles, s32 handleCount, Handle replyTarget, u64 timeout);
+Result svcCreateSharedMemory(Handle* out, size_t size, u32 local_perm, u32 other_perm);
 Result svcMapTransferMemory(Handle tmem_handle, void* addr, size_t size, u32 perm);
 Result svcUnmapTransferMemory(Handle tmem_handle, void* addr, size_t size);
 Result svcQueryPhysicalAddress(u64 out[3], u64 virtaddr);

nx/source/kernel/shmem.c

@@ -0,0 +1,85 @@
+// Copyright 2017 plutoo
+#include <switch.h>
+#include <malloc.h>
+
+Result shmemCreate(SharedMemory* s, size_t size, Permission local_perm, Permission remote_perm)
+{
+    Result rc;
+
+    s->MemHandle = INVALID_HANDLE;
+    s->Size = size;
+    s->MappedAddr = NULL;
+    s->Perm = local_perm;
+
+    rc = svcCreateSharedMemory(&s->MemHandle, size, local_perm, remote_perm);
+
+    return rc;
+}
+
+void shmemLoadRemote(SharedMemory* s, Handle handle, size_t size, Permission perm)
+{
+    s->MemHandle = handle;
+    s->Size = size;
+    s->MappedAddr = NULL;
+    s->Perm = perm;
+}
+
+Result shmemMap(SharedMemory* s)
+{
+    Result rc = 0;
+
+    if (s->MappedAddr == NULL)
+    {
+        void* addr = virtmemReserve(s->Size);
+
+        rc = svcMapSharedMemory(s->MemHandle, addr, s->Size, s->Perm);
+
+        if (R_SUCCEEDED(rc)) {
+            s->MappedAddr = addr;
+        }
+        else {
+            virtmemFree(addr, s->Size);
+        }
+    }
+    else {
+        rc = LIBNX_ALREADYMAPPED;
+    }
+
+    return rc;
+}
+
+Result shmemUnmap(SharedMemory* s)
+{
+    Result rc;
+
+    rc = svcUnmapSharedMemory(s->MemHandle, s->MappedAddr, s->Size);
+
+    if (R_SUCCEEDED(rc)) {
+        s->MappedAddr = NULL;
+    }
+
+    return rc;
+}
+
+void* shmemGetAddr(SharedMemory* s) {
+    return s->MappedAddr;
+}
+
+Result shmemClose(SharedMemory* s)
+{
+    Result rc = 0;
+
+    if (s->MappedAddr != NULL) {
+        rc = shmemUnmap(s);
+    }
+
+    if (R_SUCCEEDED(rc)) {
+        if (s->MemHandle != INVALID_HANDLE) {
+            rc = svcCloseHandle(s->MemHandle);
+        }
+
+        s->MemHandle = INVALID_HANDLE;
+    }
+
+    return rc;
+}

nx/source/kernel/svc.s

@@ -71,8 +71,13 @@ SVC_BEGIN svcClearEvent
 	ret
 SVC_END
 
-SVC_BEGIN svcCloseHandle
-	svc 0x16
+SVC_BEGIN svcMapSharedMemory
+	svc 0x13
+	ret
+SVC_END
+
+SVC_BEGIN svcUnmapSharedMemory
+	svc 0x14
 	ret
 SVC_END
 
@@ -84,6 +89,11 @@ SVC_BEGIN svcCreateTransferMemory
 	ret
 SVC_END
 
+SVC_BEGIN svcCloseHandle
+	svc 0x16
+	ret
+SVC_END
+
 SVC_BEGIN svcWaitSynchronization
 	str x0, [sp, #-16]!
 	svc 0x18
@@ -152,6 +162,14 @@ SVC_BEGIN svcReplyAndReceive
 	ret
 SVC_END
 
+SVC_BEGIN svcCreateSharedMemory
+	str x0, [sp, #-16]!
+	svc 0x50
+	ldr x2, [sp], #16
+	str w1, [x2]
+	ret
+SVC_END
+
 SVC_BEGIN svcMapTransferMemory
 	svc 0x51
 	ret