Changes in uspace/lib/net/generic/packet_remote.c [fbcdeb8:ab9378b4] in mainline

File:

• uspace/lib/net/generic/packet_remote.c (modified) (4 diffs)

uspace/lib/net/generic/packet_remote.c

@@ -38 +38 @@
 #include <async.h>
 #include <errno.h>
+#include <fibril_synch.h>
 #include <ipc/packet.h>
 #include <sys/mman.h>
@@ -46 +47 @@
 #include <net/packet.h>
 #include <net/packet_header.h>
+
+static FIBRIL_MUTEX_INITIALIZE(packet_return_lock);
 
 /** Obtain the packet from the packet server as the shared memory block.
@@ -66 +69 @@
     packet_id_t packet_id, size_t size)
 {
+        /*
+         * Prevent racing for address space with other invocations
+         * of packet_return().
+         *
+         * XXX This of course does not prevent us racing with other
+         * competitors for address space mapping.
+         */
+        fibril_mutex_lock(&packet_return_lock);
+        *packet = (packet_t *) as_get_mappable_page(size);
+        
         async_exch_t *exch = async_exchange_begin(sess);
         ipc_call_t answer;
         aid_t message = async_send_1(exch, NET_PACKET_GET, packet_id, &answer);
-        int rc = async_share_in_start_0_0(exch, size, (void *) packet);
+        int rc = async_share_in_start_0_0(exch, *packet, size);
         async_exchange_end(exch);
         
@@ -75 +88 @@
         async_wait_for(message, &result);
         
-        if (rc != EOK)
+        if (rc != EOK) {
+                munmap(*packet, size);
+                fibril_mutex_unlock(&packet_return_lock);
                 return rc;
-        
-        if (packet == (void *) -1)
-                return ENOMEM;
+        }
         
         rc = pm_add(*packet);
         if (rc != EOK) {
                 munmap(*packet, size);
+                fibril_mutex_unlock(&packet_return_lock);
                 return rc;
         }
         
+        fibril_mutex_unlock(&packet_return_lock);
         return result;
 }