X86: uv: implement a gru_read_gpa kernel function

[linux-beck.git] / drivers / misc / sgi-gru / grukservices.c

diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 766e21e15574c75ceba18828a4d492ac6a90a189..d2b149facda1d6533586bdb0021006d2c59181d3 100644 (file)
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -857,6 +857,29 @@ EXPORT_SYMBOL_GPL(gru_get_next_message);
 
 /* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/
 
+/*
+ * Load a DW from a global GPA. The GPA can be a memory or MMR address.
+ */
+int gru_read_gpa(unsigned long *value, unsigned long gpa)
+{
+       void *cb;
+       void *dsr;
+       int ret, iaa;
+
+       STAT(read_gpa);
+       if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
+               return MQE_BUG_NO_RESOURCES;
+       iaa = gpa >> 62;
+       gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA);
+       ret = gru_wait(cb);
+       if (ret == CBS_IDLE)
+               *value = *(unsigned long *)dsr;
+       gru_free_cpu_resources(cb, dsr);
+       return ret;
+}
+EXPORT_SYMBOL_GPL(gru_read_gpa);
+
+
 /*
  * Copy a block of data using the GRU resources
  */