[PATCH] habanalabs: restore vm_pgoff after mmap

From: Oded Gabbay
Date: Wed Nov 04 2020 - 09:09:37 EST


Due to using dma_mmap_coherent() to perform mmap of dma memory, we
had to clear the vm_pgoff field before calling that function.

However, that broke the userspace (profiler tool) as they relied
on searching the /proc/self/maps for these values to correctly
"disassemble" the topology recipe.

To re-enable that functionality, the driver can simply restore the
value of vm_pgoff before returning to userspace but after calling
dma_mmap_coherent().

Signed-off-by: Oded Gabbay <ogabbay@xxxxxxxxxx>
---
drivers/misc/habanalabs/common/command_buffer.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/misc/habanalabs/common/command_buffer.c b/drivers/misc/habanalabs/common/command_buffer.c
index 360dc340b2f4..b30249e4d3b7 100644
--- a/drivers/misc/habanalabs/common/command_buffer.c
+++ b/drivers/misc/habanalabs/common/command_buffer.c
@@ -518,6 +518,7 @@ int hl_cb_mmap(struct hl_fpriv *hpriv, struct vm_area_struct *vma)
}

cb->mmap_size = cb->size;
+ vma->vm_pgoff = handle;

return 0;

--
2.17.1