[PATCH] kernel: Export mm_access

[Felix Kuehling]

From: Harish Kasiviswanathan <Harish.Kasiviswanathan@xxxxxxx>

Exporting mm_access, which is required for implementing accelerated
equivalents of process_vm_readv/process_vm_writev for GPU memory in KFD
(AMD's GPU compute driver). This allows us to apply all the same remote
process memory access policies.

Signed-off-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@xxxxxxx>
Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
---
Current KFD with AMD discrete GPU support is not yet upstream, but we
are working on getting it upstream for 4.13 or 4.14 depending on how we
line up with Dave Airlie's merge windows.

For reference, recent releases of ROCm (AMD's Radeon Open Compute
Platform software stack) with fully open-source user mode and kernel
code can be found on GitHub:
https://github.com/RadeonOpenCompute/ROCK-Kernel-Driver/tree/roc-1.5.0

 kernel/fork.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/fork.c b/kernel/fork.c
index aa1076c..0849896 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1060,6 +1060,7 @@ struct mm_struct *mm_access(struct task_struct
*task, unsigned int mode)

 	return mm;
 }
+EXPORT_SYMBOL_GPL(mm_access);

 static void complete_vfork_done(struct task_struct *tsk)
 {