From e7317cca98d74c63456b4a72eba896ef42e25413 Mon Sep 17 00:00:00 2001
From: "Masamichi Takagi m-takagi@ab.jp.nec.com" <takagi@kncc-login1.(none)>
Date: Tue, 30 Oct 2012 21:32:49 +0900
Subject: [PATCH] make munmap free physical pages, and one correction for
 aligned mmap in syscall.c (extend_process_region is called with memory-region
 start-address which is aligned (map_end_aligned), instead of tail-address of
 current-region (region->map_end)) for aligned mmap (in syscall.c)

---
 kernel/include/page.h    |  1 +
 kernel/include/process.h |  4 ++--
 kernel/mem.c             |  6 ++++++
 kernel/process.c         | 19 +++++++++++++------
 kernel/syscall.c         | 14 +++++++++-----
 5 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/kernel/include/page.h b/kernel/include/page.h
index 41b456d7..b7b6354c 100644
--- a/kernel/include/page.h
+++ b/kernel/include/page.h
@@ -2,6 +2,7 @@
 #define __HEADER_PAGE_H
 
 void *allocate_pages(int npages, enum aal_mc_ap_flag flag);
+void free_pages_pa(unsigned long pa, int npages);
 void free_pages(void *va, int npages);
 
 #endif
diff --git a/kernel/include/process.h b/kernel/include/process.h
index f1bbf217..4bd14ed8 100644
--- a/kernel/include/process.h
+++ b/kernel/include/process.h
@@ -92,8 +92,8 @@ int add_process_memory_range(struct process *process,
 int add_process_large_range(struct process *process,
                             unsigned long start, unsigned long end,
                             unsigned long flag, unsigned long *phys);
-int remove_process_region(struct process *proc,
-                          unsigned long start, unsigned long end);
+int remove_process_region(struct process *proc, unsigned long va_start, unsigned long va_end, unsigned long pa);
+
 struct program_load_desc;
 void init_process_stack(struct process *process, struct program_load_desc *pn,
                         int argc, char **argv, 
diff --git a/kernel/mem.c b/kernel/mem.c
index 44487d81..e4863117 100644
--- a/kernel/mem.c
+++ b/kernel/mem.c
@@ -40,6 +40,12 @@ void *allocate_pages(int npages, enum aal_mc_ap_flag flag)
 	return pa ? phys_to_virt(pa) : 0; 
 }
 
+void free_pages_pa(unsigned long pa, int npages)
+{
+    kprintf("mem.c,free_pages_pa,pa=%lx\n", pa);
+	aal_pagealloc_free(pa_allocator, pa, npages);
+}
+
 void free_pages(void *va, int npages)
 {
 	aal_pagealloc_free(pa_allocator, virt_to_phys(va), npages);
diff --git a/kernel/process.c b/kernel/process.c
index 412aaee8..3dc4214a 100644
--- a/kernel/process.c
+++ b/kernel/process.c
@@ -283,22 +283,29 @@ unsigned long extend_process_region(struct process *proc,
 	return address;
 }
 
-int remove_process_region(struct process *proc,
-                          unsigned long start, unsigned long end)
+int remove_process_region(struct process *proc, unsigned long va_start, unsigned long va_end, unsigned long pa)
 {
     unsigned long flags;
-	if ((start & (PAGE_SIZE - 1)) || (end & (PAGE_SIZE - 1))) {
+	if ((va_start & (PAGE_SIZE - 1)) || (va_end & (PAGE_SIZE - 1))) {
 		return -EINVAL;
 	}
 
     flags = aal_mc_spinlock_lock(&proc->vm->page_table_lock);
 	/* We defer freeing to the time of exit */
-	while (start < end) {
-		aal_mc_pt_clear_page(proc->vm->page_table, (void *)start);
-		start += PAGE_SIZE;
+    unsigned long va = va_start;
+	while (va < va_end) {
+		aal_mc_pt_clear_page(proc->vm->page_table, (void *)va);
+		va += PAGE_SIZE;
 	}
     aal_mc_spinlock_unlock(&proc->vm->page_table_lock, flags);
 
+    // we skip freeing "range"
+
+#if 1
+    kprintf("process.c,free_pages,pa=%lx,start=%lx,end=%lx\n", pa, va_start, va_end);
+    free_pages_pa(pa, (va_end - va_start) / PAGE_SIZE);
+#endif
+
 	return 0;
 }
 
diff --git a/kernel/syscall.c b/kernel/syscall.c
index c472a30c..b89582d8 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -411,7 +411,7 @@ SYSCALL_DECLARE(mmap)
 		region->map_end = 
 			extend_process_region(cpu_local_var(current),
 			                      region->map_start,
-			                      region->map_end,
+			                      map_end_aligned,
 			                      s + len);
         aal_mc_spinlock_unlock(&cpu_local_var(current)->vm->memory_range_lock, flags);
         //        kprintf("syscall.c,mmap,map_end=%lx,s+len=%lx\n", region->map_end, s+len);
@@ -457,13 +457,17 @@ SYSCALL_DECLARE(mmap)
 
 SYSCALL_DECLARE(munmap)
 {
-	unsigned long address, len;
+	unsigned long va, pa, len;
+    int r;
 
-	address = aal_mc_syscall_arg0(ctx);
+	va = aal_mc_syscall_arg0(ctx);
 	len = aal_mc_syscall_arg1(ctx);
 
-	return remove_process_region(cpu_local_var(current), address, 
-	                             address + len);
+    if(aal_mc_pt_virt_to_phys(cpu_local_var(current)->vm->page_table, (void *)va, &pa)) {
+        return -EFAULT; 
+    }
+    r = remove_process_region(cpu_local_var(current), va, va + len, pa);
+	return r;
 }
 
 SYSCALL_DECLARE(mprotect)