dsp: msm_audio_ion: unmap dma only if unmap kernel succeeds

If buf unmap is executed without successful kernel unmap
the vmap counter mismatches. Check for error scenarios in
kernel unmap function and ignore buf unmap if not necessary.

Change-Id: I3c5835dcdfe05db4baaa5cf904995ed8f89e9cfe
Signed-off-by: Karthikeyan Mani <[email protected]>

dsp/msm_audio_ion.c

@@ -279,7 +279,7 @@ exit:
 	return addr;
 }
 
-static void msm_audio_ion_unmap_kernel(struct dma_buf *dma_buf)
+static int msm_audio_ion_unmap_kernel(struct dma_buf *dma_buf)
 {
 	int rc = 0;
 	void *vaddr = NULL;
@@ -304,6 +304,7 @@ static void msm_audio_ion_unmap_kernel(struct dma_buf *dma_buf)
 		dev_err(cb_dev,
 			"%s: cannot find allocation for dma_buf %pK",
 			__func__, dma_buf);
+		rc = -EINVAL;
 		goto err;
 	}
 
@@ -317,7 +318,7 @@ static void msm_audio_ion_unmap_kernel(struct dma_buf *dma_buf)
 	}
 
 err:
-	return;
+	return rc;
 }
 
 static int msm_audio_ion_map_buf(struct dma_buf *dma_buf, dma_addr_t *paddr,
@@ -489,12 +490,16 @@ EXPORT_SYMBOL(msm_audio_ion_import);
  */
 int msm_audio_ion_free(struct dma_buf *dma_buf)
 {
+	int ret = 0;
+
 	if (!dma_buf) {
 		pr_err("%s: dma_buf invalid\n", __func__);
 		return -EINVAL;
 	}
 
-	msm_audio_ion_unmap_kernel(dma_buf);
+	ret = msm_audio_ion_unmap_kernel(dma_buf);
+	if (ret)
+		return ret;
 
 	msm_audio_dma_buf_unmap(dma_buf);