From 8436f5a5ac3a65d7ec4a6de6245490ae0431618f Mon Sep 17 00:00:00 2001
From: NAKAMURA Gou <go.nakamura.yw@hitachi-solutions.com>
Date: Tue, 11 Jun 2013 13:44:23 +0900
Subject: [PATCH] add remove_process_memory_range()

---
 kernel/include/process.h |  2 +
 kernel/process.c         | 90 ++++++++++++++++++++++++++++++++++++++++
 kernel/syscall.c         |  8 +++-
 3 files changed, 98 insertions(+), 2 deletions(-)

diff --git a/kernel/include/process.h b/kernel/include/process.h
index b3e0b44d..4d12eaa3 100644
--- a/kernel/include/process.h
+++ b/kernel/include/process.h
@@ -98,6 +98,8 @@ void free_process_memory(struct process *proc);
 int add_process_memory_range(struct process *process,
                              unsigned long start, unsigned long end,
                              unsigned long phys, unsigned long flag);
+int remove_process_memory_range(
+		struct process *process, unsigned long start, unsigned long end);
 int remove_process_region(struct process *proc,
                           unsigned long start, unsigned long end);
 struct program_load_desc;
diff --git a/kernel/process.c b/kernel/process.c
index 991f435c..55297e32 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -171,6 +171,96 @@ err:
 	return -ENOMEM;
 }
 
+int remove_process_memory_range(struct process *process, unsigned long start, unsigned long end)
+{
+	struct process_vm * const vm = process->vm;
+	struct vm_range *range;
+	struct vm_range *next;
+	int error;
+	unsigned long freestart;
+	unsigned long freephys;
+	unsigned long freesize;
+	struct vm_range *freerange;
+	struct vm_range *newrange;
+
+	list_for_each_entry_safe(range, next, &vm->vm_range_list, list) {
+		if ((range->end <= start) || (end <= range->start)) {
+			/* no overlap */
+			continue;
+		}
+
+		error = 0;
+		freerange = NULL;
+		freesize = 0;
+
+		if (start <= range->start) {
+			/* partial or whole delete from range->start */
+			freestart = range->start;
+			freephys = range->phys;
+			freesize = end - range->start;
+
+			if (freesize >= (range->end - range->start)) {
+				freesize = range->end - range->start;
+				list_del(&range->list);
+				freerange = range;
+			}
+			else {
+				range->start += freesize;
+				range->phys += freesize;
+			}
+		}
+		else if (range->end <= end) {
+			/* partial delete up to range->end */
+			freestart = start;
+			freephys = range->phys + (start - range->start);
+			freesize = range->end - start;
+
+			range->end = start;
+		}
+		else {
+			/* delete the middle part of the 'range' */
+			freestart = start;
+			freephys = range->phys + (start - range->start);
+			freesize = end - start;
+
+			newrange = kmalloc(sizeof(struct vm_range), IHK_MC_AP_NOWAIT);
+			if (!newrange) {
+				kprintf("remove_process_memory_range:kmalloc failed\n");
+				return -ENOMEM;
+			}
+			INIT_LIST_HEAD(&range->list);
+			newrange->start = end;
+			newrange->end = range->end;
+			newrange->phys = range->phys + (end - range->start);
+			newrange->flag = range->flag;
+			list_add_tail(&newrange->list, &vm->vm_range_list);
+
+			range->end = start;
+		}
+
+		if (freesize > 0) {
+			error = remove_process_region(process, freestart, (freestart + freesize));
+			if (error) {
+				kprintf("remove_process_memory_range:remove_process_region failed: %d\n", error);
+				/* through */
+			}
+
+			if (!(range->flag & (VR_REMOTE | VR_IO_NOCACHE | VR_RESERVED))) {
+				// XXX: need TLB shootdown?
+				ihk_mc_free_pages(phys_to_virt(freephys), freesize>>PAGE_SHIFT);
+			}
+		}
+		if (freerange != NULL) {
+			ihk_mc_free(freerange);
+		}
+		if (error) {
+			return error;
+		}
+	}
+
+	return 0;
+}
+
 int add_process_memory_range(struct process *process,
                              unsigned long start, unsigned long end,
                              unsigned long phys, unsigned long flag)
diff --git a/kernel/syscall.c b/kernel/syscall.c
index ea1f2b5d..c8e620ac 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -506,12 +506,16 @@ SYSCALL_DECLARE(mmap)
 SYSCALL_DECLARE(munmap)
 {
 	unsigned long address, len;
+	int error;
 
 	address = ihk_mc_syscall_arg0(ctx);
 	len = ihk_mc_syscall_arg1(ctx);
 
-	return remove_process_region(cpu_local_var(current), address, 
-	                             address + len);
+	ihk_mc_spinlock_lock_noirq(&cpu_local_var(current)->vm->memory_range_lock);
+	error = remove_process_memory_range(cpu_local_var(current), address, address+len);
+	ihk_mc_spinlock_unlock_noirq(&cpu_local_var(current)->vm->memory_range_lock);
+
+	return error;
 }
 
 SYSCALL_DECLARE(mprotect)