libdce: Add mutex protection for dce_buf_lock/dce_buf_unlock

The dce_buf_lock and dce_buf_unlock are meant for any video
buffer locking and unlocking with the GEM allocator.
Currently, these methods are being called from libdce apis
with ipc mutex held. In order to enable other media components
to make use of these buffer lock/unlock apis, explicit ipc mutex
protection is added.

Change-Id: I6d63a4cdcffec62a346341ff515a7ebb03dea8c0
Signed-off-by: Sunita Nadampalli <sunitan@ti.com>

3 files changed, 18 insertions, 2 deletions

diff --git a/libdce.c b/libdce.c
index 6b664bd..881516e 100644
--- a/libdce.c
+++ b/libdce.c
@@ -50,7 +50,7 @@
 /* Handle used for Remote Communication              */
 MmRpc_Handle    MmRpcHandle[MAX_REMOTEDEVICES] = { NULL};
 Engine_Handle   gEngineHandle[MAX_INSTANCES][MAX_REMOTEDEVICES] = { {NULL, NULL}};
-static pthread_mutex_t    ipc_mutex = PTHREAD_MUTEX_INITIALIZER;
+pthread_mutex_t    ipc_mutex = PTHREAD_MUTEX_INITIALIZER;
 static int      __ClientCount[MAX_REMOTEDEVICES] = {0};
 int             dce_debug = DCE_DEBUG_LEVEL;
 const String DCE_DEVICE_NAME[MAX_REMOTEDEVICES]= {"rpmsg-dce","rpmsg-dce-dsp"};
diff --git a/libdce_android.c b/libdce_android.c
index 300c311..9480926 100644
--- a/libdce_android.c
+++ b/libdce_android.c
@@ -33,6 +33,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
+#include <pthread.h>
 
 #include <ti/ipc/mm/MmRpc.h>
 #include "dce_priv.h"
@@ -42,6 +43,7 @@
 
 
 extern MmRpc_Handle    MmRpcHandle[];
+extern pthread_mutex_t    ipc_mutex;
 
 int dce_buf_lock(int num, size_t *handle)
 {
@@ -49,6 +51,8 @@ int dce_buf_lock(int num, size_t *handle)
     MmRpc_BufDesc      *desc = NULL;
     dce_error_status    eError = DCE_EOK;
 
+    pthread_mutex_lock(&ipc_mutex);
+
     _ASSERT(num > 0, DCE_EINVALID_INPUT);
 
     desc = malloc(num * sizeof(MmRpc_BufDesc));
@@ -65,6 +69,8 @@ EXIT:
     if( desc ) {
         free(desc);
     }
+    pthread_mutex_unlock(&ipc_mutex);
+
     return (eError);
 }
 
@@ -74,6 +80,8 @@ int dce_buf_unlock(int num, size_t *handle)
     MmRpc_BufDesc      *desc = NULL;
     dce_error_status    eError = DCE_EOK;
 
+    pthread_mutex_lock(&ipc_mutex);
+
     _ASSERT(num > 0, DCE_EINVALID_INPUT);
 
     desc = malloc(num * sizeof(MmRpc_BufDesc));
@@ -90,6 +98,9 @@ EXIT:
     if( desc ) {
         free(desc);
     }
+
+    pthread_mutex_unlock(&ipc_mutex);
+
     return (eError);
 }
 
diff --git a/memplugin_android.c b/memplugin_android.c
index d2f5b35..307dc9e 100644
--- a/memplugin_android.c
+++ b/memplugin_android.c
@@ -34,7 +34,7 @@
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <sys/eventfd.h>
-#include <fcntl.h>
+#include <pthread.h>
 
 #include "memplugin.h"
 #include "libdce.h"
@@ -50,6 +50,7 @@
 
 int                    OmapDrm_FD  = INVALID_DRM_FD;
 struct omap_device    *OmapDev     = NULL;
+extern pthread_mutex_t    ipc_mutex;
 
 int memplugin_open()
 {
@@ -70,6 +71,10 @@ int memplugin_open()
         return MEM_EOPEN_FAILURE;
     }
 
+    pthread_mutexattr_t attr;
+    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+    pthread_mutex_init(&ipc_mutex, &attr);
+
     if (dce_ipc_init(IPU) != MEM_EOK) {
         omap_device_del(OmapDev);
         OmapDev = NULL;