From 5d9efa72419179f8909d62e18665784282d3201c Mon Sep 17 00:00:00 2001
From: Tomoki Shirasawa <sira@popeye.cc.u-tokyo.ac.jp>
Date: Sun, 2 Jun 2013 13:54:38 +0900
Subject: [PATCH] add rollback when ihk_mc_pt_set_page returns error

---
 arch/x86/kernel/memory.c |  5 +++++
 kernel/process.c         | 33 ++++++++++++++++++++++++++++-----
 lib/include/ihk/mm.h     |  1 +
 3 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/memory.c b/arch/x86/kernel/memory.c
index fe6077fe..34d20626 100644
--- a/arch/x86/kernel/memory.c
+++ b/arch/x86/kernel/memory.c
@@ -621,6 +621,11 @@ int ihk_mc_pt_clear_page(page_table_t pt, void *virt)
 	return __clear_pt_page(pt, virt, 0);
 }
 
+int ihk_mc_pt_clear_large_page(page_table_t pt, void *virt)
+{
+	return __clear_pt_page(pt, virt, 1);
+}
+
 void load_page_table(struct page_table *pt)
 {
 	unsigned long pt_addr;
diff --git a/kernel/process.c b/kernel/process.c
index 51cc4566..cdc8d1db 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -112,7 +112,7 @@ static int update_process_page_table(struct process *process,
                           struct vm_range *range, enum ihk_mc_pt_attribute flag)
 {
 	unsigned long p, pa = range->phys;
-
+	unsigned long pp;
 	unsigned long flags = ihk_mc_spinlock_lock(&process->vm->page_table_lock);
 	p = range->start;
 	while (p < range->end) {
@@ -125,8 +125,7 @@ static int update_process_page_table(struct process *process,
 
 			if (ihk_mc_pt_set_large_page(process->vm->page_table, (void *)p,
 					pa, PTATTR_WRITABLE | PTATTR_USER | flag) != 0) {
-				kprintf("ERROR:setting large page for 0x%lX -> 0x%lX\n", p, pa);
-				panic("");
+				goto err;
 			}
 
 			dkprintf("large page set for 0x%lX -> 0x%lX\n", p, pa);
@@ -138,8 +137,7 @@ static int update_process_page_table(struct process *process,
 #endif		
 			if(ihk_mc_pt_set_page(process->vm->page_table, (void *)p,
 			      pa, PTATTR_WRITABLE | PTATTR_USER | flag) != 0){
-				ihk_mc_spinlock_unlock(&process->vm->page_table_lock, flags);
-				return -ENOMEM;
+				goto err;
 			}
 
 			pa += PAGE_SIZE;
@@ -150,6 +148,31 @@ static int update_process_page_table(struct process *process,
 	}
 	ihk_mc_spinlock_unlock(&process->vm->page_table_lock, flags);
 	return 0;
+
+err:
+	pp = range->start;
+	pa = range->phys;
+	while(pp < p){
+#ifdef USE_LARGE_PAGES
+		if ((p & (LARGE_PAGE_SIZE - 1)) == 0 && 
+				(pa & (LARGE_PAGE_SIZE - 1)) == 0 &&
+				(range->end - p) >= LARGE_PAGE_SIZE) {
+			ihk_mc_pt_clear_large_page(process->vm->page_table, (void *)pp);
+			pa += LARGE_PAGE_SIZE;
+			pp += LARGE_PAGE_SIZE;
+		}
+		else{
+#endif
+			ihk_mc_pt_clear_page(process->vm->page_table, (void *)pp);
+			pa += PAGE_SIZE;
+			pp += PAGE_SIZE;
+#ifdef USE_LARGE_PAGES
+		}
+#endif
+	}
+
+	ihk_mc_spinlock_unlock(&process->vm->page_table_lock, flags);
+	return -ENOMEM;
 }
 
 #if 0
diff --git a/lib/include/ihk/mm.h b/lib/include/ihk/mm.h
index 7cdd5034..b619181c 100644
--- a/lib/include/ihk/mm.h
+++ b/lib/include/ihk/mm.h
@@ -91,6 +91,7 @@ int ihk_mc_pt_set_large_page(page_table_t pt, void *virt,
 int ihk_mc_pt_change_page(page_table_t pt, void *virt,
                           enum ihk_mc_pt_attribute);
 int ihk_mc_pt_clear_page(page_table_t pt, void *virt);
+int ihk_mc_pt_clear_large_page(page_table_t pt, void *virt);
 int ihk_mc_pt_prepare_map(page_table_t pt, void *virt, unsigned long size,
                           enum ihk_mc_pt_prepare_flag);