From 532b5fece258134d82a71cb0dcd4c9e4ba3e2eee Mon Sep 17 00:00:00 2001
From: Zhenhua Huang <zhenhuah@codeaurora.org>
Date: Wed, 22 Jul 2020 11:29:39 +0800
Subject: [PATCH] soc: qcom: secure_buffer: track all hyp based secure pages

To track all secure pages which are not stage 2 mapped to APPS, add a
MAGIC in page->private.

Change-Id: I4674f74eca95eeb36f004185a5d9cb0d63d558b0
Signed-off-by: Zhenhua Huang <zhenhuah@codeaurora.org>
---
 drivers/soc/qcom/secure_buffer.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/soc/qcom/secure_buffer.c b/drivers/soc/qcom/secure_buffer.c
index 7d6d2ecdbdf6..6697fca0c3f2 100644
--- a/drivers/soc/qcom/secure_buffer.c
+++ b/drivers/soc/qcom/secure_buffer.c
@@ -145,6 +145,22 @@ static int batched_hyp_assign(struct sg_table *table, u32 *source_vmids,
 	return ret;
 }
 
+static inline void set_each_page_of_sg(struct sg_table *table, u64 flag)
+{
+	struct scatterlist *sg;
+	int npages;
+	int i = 0;
+
+	for_each_sg(table->sgl, sg, table->nents, i) {
+		npages = sg->length / PAGE_SIZE;
+		if (sg->length % PAGE_SIZE)
+			npages++;
+		while (npages--)
+			set_page_private(nth_page(sg_page(sg), npages), flag);
+	}
+}
+
+#define SECURE_PAGE_MAGIC 0xEEEEEEEE
 /*
  *  When -EADDRNOTAVAIL is returned the memory may no longer be in
  *  a usable state and should no longer be accessed by the HLOS.
@@ -206,6 +222,19 @@ int hyp_assign_table(struct sg_table *table,
 	ret = batched_hyp_assign(table, source_vm_copy, source_vm_copy_size,
 				 dest_vm_copy, dest_vm_copy_size);
 
+	if (!ret) {
+		while (dest_nelems--) {
+			if (dest_vmids[dest_nelems] == VMID_HLOS)
+				break;
+		}
+
+		if (dest_nelems == -1)
+			set_each_page_of_sg(table, SECURE_PAGE_MAGIC);
+		else
+			set_each_page_of_sg(table, 0);
+	}
+
+
 	dma_unmap_single(qcom_secure_buffer_dev, dest_dma_addr,
 			 dest_vm_copy_size, DMA_TO_DEVICE);
 out_free_dest: