From e63215e367d5d519a4d85cc5db3ba49d5cb33a1f Mon Sep 17 00:00:00 2001
From: ZhaoXi <fly0307@sjtu.edu.cn>
Date: Tue, 21 Nov 2023 14:29:36 +0800
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=9E=20fix(penglai-enclave-driver):?=
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Add a sbi call to reclaim memory and clear pmp settings when uninstalling the pontoon module; add the release operation for kmalloc data.

Mainly for issue: Facing kernel panic for openEuler 23.09
---
 .../penglai-enclave-driver.c                  | 43 +++++++++++++------
 penglai-enclave-driver/penglai-enclave.c      | 11 +++--
 penglai-enclave-driver/penglai-enclave.h      |  3 +-
 3 files changed, 37 insertions(+), 20 deletions(-)

diff --git a/penglai-enclave-driver/penglai-enclave-driver.c b/penglai-enclave-driver/penglai-enclave-driver.c
index f9b16034d..30c0c3cd2 100644
--- a/penglai-enclave-driver/penglai-enclave-driver.c
+++ b/penglai-enclave-driver/penglai-enclave-driver.c
@@ -77,22 +77,39 @@ int enclave_ioctl_init(void)
 //static void enclave_ioctl_exit(void)
 void enclave_ioctl_exit(void)
 {
-	//unsigned long size, addr, order, count;
+	unsigned long addr, order, count;
+	unsigned long *size = kmalloc(sizeof(unsigned long), GFP_KERNEL);
+	;
+	struct sbiret sbiret;
 	printk("enclave_ioctl_exit...\n");
 
-	//TODO: free SM memory
-	/*while((addr = SBI_CALL_2(SBI_SM_FREE_ENCLAVE_MEM, &size, FREE_MAX_MEMORY)))
-	  {
-	  order = ilog2(size-1) + 1;
-	  count = 0x1 << order;
-	  if(count != size)
-	  {
-	  printk("KERNEL MODULE:  the number of free pages is not exponential times of two\n");
-	  return;
-	  }
-	  free_pages((long unsigned int)__va(addr), order);
-	  }*/
+	
+	sbiret = SBI_CALL_2(SBI_SM_FREE_ENCLAVE_MEM, __pa(size), FREE_MAX_MEMORY);
+
+	addr = (unsigned long)(sbiret.value);
+	while (addr)
+	{
+		order = ilog2((*size) - 1) + 1;
+		count = 0x1 << order;
+		if (count != (*size) && (*size > 0))
+		{
+			printk("KERNEL MODULE:  the number of free pages is not exponential times of two\n");
+			kfree(size);
+			return;
+		}
+		printk("KERNEL MODULE:  free secmem:paddr:%lx, vaddr:%lx, order:%lu\n", addr, __va(addr), order);
+		if ((*size) > 0)
+		{
+			free_pages((long unsigned int)__va(addr), (order - RISCV_PGSHIFT));
+		}
+
+		sbiret = SBI_CALL_2(SBI_SM_FREE_ENCLAVE_MEM, __pa(size), FREE_MAX_MEMORY);
 
+		addr = (unsigned long)(sbiret.value);
+	}
+
+deregister_device:
+	kfree(size);
 	misc_deregister(&enclave_dev);
 	return;
 }
diff --git a/penglai-enclave-driver/penglai-enclave.c b/penglai-enclave-driver/penglai-enclave.c
index 222a3360f..3e270f83f 100644
--- a/penglai-enclave-driver/penglai-enclave.c
+++ b/penglai-enclave-driver/penglai-enclave.c
@@ -76,7 +76,7 @@ enclave_t* create_enclave(int total_pages)
 	while(ret.value == ENCLAVE_NO_MEMORY)
 	{
 		//TODO: allocate certain memory region like sm_init instead of allocating size of one enclave
-		addr = __get_free_pages(GFP_HIGHUSER, order);
+		addr = __get_free_pages(GFP_ATOMIC, order);
 		if(!addr)
 		{
 			printk("KERNEL MODULE: can not get free page which order is 0x%lx", order);
@@ -113,7 +113,7 @@ enclave_t* create_enclave(int total_pages)
 	enclave->enclave_mem = enclave_mem;
 	enclave->untrusted_mem = untrusted_mem;
 
-    kfree(untrusted_mem);
+    kfree(require_sec_memory);
 	spin_unlock_bh(&kmalloc_enclave_lock);
 	//TODO: create untrusted mem
 
@@ -124,7 +124,7 @@ enclave_t* create_enclave(int total_pages)
 	if(enclave) kfree(enclave);
 	if(enclave_mem) kfree(enclave_mem);
 	if(untrusted_mem) kfree(untrusted_mem);
-    if(require_sec_memory) kfree(untrusted_mem);
+    if(require_sec_memory) kfree(require_sec_memory);
 
 	return NULL;
 }
@@ -143,9 +143,8 @@ int destroy_enclave(enclave_t* enclave)
 	enclave_mem = enclave->enclave_mem;
 	untrusted_mem = enclave->untrusted_mem;
 	enclave_mem_destroy(enclave_mem);
-
-	kfree(enclave_mem);
-	kfree(untrusted_mem);
+	if(enclave_mem)kfree(enclave_mem);
+	if(untrusted_mem)kfree(untrusted_mem);
 	kfree(enclave);
 
 	return 0;
diff --git a/penglai-enclave-driver/penglai-enclave.h b/penglai-enclave-driver/penglai-enclave.h
index 616e4a775..02d68ac64 100644
--- a/penglai-enclave-driver/penglai-enclave.h
+++ b/penglai-enclave-driver/penglai-enclave.h
@@ -28,7 +28,8 @@
 #define SBI_SM_DESTROY_ENCLAVE           94
 #define SBI_SM_ALLOC_ENCLAVE_MEM         93
 #define SBI_SM_MEMORY_EXTEND             92
-#define SBI_SM_FREE_ENCLAVE_MEM          91
+#define SBI_SM_MEMORY_RECLAIM      		 91
+#define SBI_SM_FREE_ENCLAVE_MEM          90
 #define SBI_SM_DEBUG_PRINT               88
 
 //Error codes of SBI_SM_ALLOC_ENCLAVE_MEM