X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fmremap.c;h=a39b7b91be46722789a0ce95ed5382405796077c;hb=0a0dd05dd7e1a800241888cbf515bf8d3dc2e59c;hp=8de77b632a206b5865a8d3a59c3c89cd25d4fa28;hpb=c74df32c724a1652ad8399b4891bb02c9d43743a;p=safe%2Fjmp%2Flinux-2.6

diff --git a/mm/mremap.c b/mm/mremap.c
index 8de77b6..a39b7b9 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -3,7 +3,7 @@
  *
  *	(C) Copyright 1996 Linus Torvalds
  *
- *	Address space accounting code	<alan@redhat.com>
+ *	Address space accounting code	<alan@lxorguk.ukuu.org.uk>
  *	(C) Copyright 2002 Red Hat Inc, All Rights Reserved
  */
 
@@ -13,15 +13,19 @@
 #include <linux/shm.h>
 #include <linux/mman.h>
 #include <linux/swap.h>
+#include <linux/capability.h>
 #include <linux/fs.h>
 #include <linux/highmem.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
+#include <linux/mmu_notifier.h>
 
 #include <asm/uaccess.h>
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
+#include "internal.h"
+
 static pmd_t *get_old_pmd(struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
@@ -72,8 +76,12 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
 	struct address_space *mapping = NULL;
 	struct mm_struct *mm = vma->vm_mm;
 	pte_t *old_pte, *new_pte, pte;
-	spinlock_t *old_ptl;
+	spinlock_t *old_ptl, *new_ptl;
+	unsigned long old_start;
 
+	old_start = old_addr;
+	mmu_notifier_invalidate_range_start(vma->vm_mm,
+					    old_start, old_end);
 	if (vma->vm_file) {
 		/*
 		 * Subtle point from Rajesh Venkatasubramanian: before
@@ -88,28 +96,39 @@ static void move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd,
 			new_vma->vm_truncate_count = 0;
 	}
 
+	/*
+	 * We don't have to worry about the ordering of src and dst
+	 * pte locks because exclusive mmap_sem prevents deadlock.
+	 */
 	old_pte = pte_offset_map_lock(mm, old_pmd, old_addr, &old_ptl);
  	new_pte = pte_offset_map_nested(new_pmd, new_addr);
+	new_ptl = pte_lockptr(mm, new_pmd);
+	if (new_ptl != old_ptl)
+		spin_lock_nested(new_ptl, SINGLE_DEPTH_NESTING);
+	arch_enter_lazy_mmu_mode();
 
 	for (; old_addr < old_end; old_pte++, old_addr += PAGE_SIZE,
 				   new_pte++, new_addr += PAGE_SIZE) {
 		if (pte_none(*old_pte))
 			continue;
 		pte = ptep_clear_flush(vma, old_addr, old_pte);
-		/* ZERO_PAGE can be dependant on virtual addr */
 		pte = move_pte(pte, new_vma->vm_page_prot, old_addr, new_addr);
 		set_pte_at(mm, new_addr, new_pte, pte);
 	}
 
+	arch_leave_lazy_mmu_mode();
+	if (new_ptl != old_ptl)
+		spin_unlock(new_ptl);
 	pte_unmap_nested(new_pte - 1);
 	pte_unmap_unlock(old_pte - 1, old_ptl);
 	if (mapping)
 		spin_unlock(&mapping->i_mmap_lock);
+	mmu_notifier_invalidate_range_end(vma->vm_mm, old_start, old_end);
 }
 
 #define LATENCY_LIMIT	(64 * PAGE_SIZE)
 
-static unsigned long move_page_tables(struct vm_area_struct *vma,
+unsigned long move_page_tables(struct vm_area_struct *vma,
 		unsigned long old_addr, struct vm_area_struct *new_vma,
 		unsigned long new_addr, unsigned long len)
 {
@@ -221,8 +240,8 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 	if (vm_flags & VM_LOCKED) {
 		mm->locked_vm += new_len >> PAGE_SHIFT;
 		if (new_len > old_len)
-			make_pages_present(new_addr + old_len,
-					   new_addr + new_len);
+			mlock_vma_pages_range(new_vma, new_addr + old_len,
+						       new_addr + new_len);
 	}
 
 	return new_addr;
@@ -280,6 +299,10 @@ unsigned long do_mremap(unsigned long addr,
 		if ((addr <= new_addr) && (addr+old_len) > new_addr)
 			goto out;
 
+		ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
+		if (ret)
+			goto out;
+
 		ret = do_munmap(mm, new_addr, new_len);
 		if (ret)
 			goto out;
@@ -314,7 +337,7 @@ unsigned long do_mremap(unsigned long addr,
 	/* We can't remap across vm area boundaries */
 	if (old_len > vma->vm_end - addr)
 		goto out;
-	if (vma->vm_flags & VM_DONTEXPAND) {
+	if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) {
 		if (new_len > old_len)
 			goto out;
 	}
@@ -358,7 +381,7 @@ unsigned long do_mremap(unsigned long addr,
 			vm_stat_account(mm, vma->vm_flags, vma->vm_file, pages);
 			if (vma->vm_flags & VM_LOCKED) {
 				mm->locked_vm += pages;
-				make_pages_present(addr + old_len,
+				mlock_vma_pages_range(vma, addr + old_len,
 						   addr + new_len);
 			}
 			ret = addr;
@@ -379,8 +402,13 @@ unsigned long do_mremap(unsigned long addr,
 
 			new_addr = get_unmapped_area(vma->vm_file, 0, new_len,
 						vma->vm_pgoff, map_flags);
-			ret = new_addr;
-			if (new_addr & ~PAGE_MASK)
+			if (new_addr & ~PAGE_MASK) {
+				ret = new_addr;
+				goto out;
+			}
+
+			ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
+			if (ret)
 				goto out;
 		}
 		ret = move_vma(vma, addr, old_len, new_len, new_addr);
@@ -392,9 +420,9 @@ out_nc:
 	return ret;
 }
 
-asmlinkage unsigned long sys_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr)
+SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len,
+		unsigned long, new_len, unsigned long, flags,
+		unsigned long, new_addr)
 {
 	unsigned long ret;