add uksm 0.1.2.3 for v3.10 .ge.46.patch

Conflicts:
	fs/exec.c

Signed-off-by: Stefan Guendhoer <stefan@guendhoer.com>

1 files changed, 43 insertions, 6 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index ceb1b5732..18856ffca 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -36,6 +36,7 @@
 #include <linux/sched/sysctl.h>
 #include <linux/notifier.h>
 #include <linux/memory.h>
+#include <linux/ksm.h>
 
 #include <asm/uaccess.h>
 #include <asm/cacheflush.h>
@@ -65,7 +66,7 @@ static void unmap_region(struct mm_struct *mm,
  * MAP_SHARED	r: (no) no	r: (yes) yes	r: (no) yes	r: (no) yes
  *		w: (no) no	w: (no) no	w: (yes) yes	w: (no) no
  *		x: (no) no	x: (no) yes	x: (no) yes	x: (yes) yes
- *		
+ *
  * MAP_PRIVATE	r: (no) no	r: (yes) yes	r: (no) yes	r: (no) yes
  *		w: (no) no	w: (no) no	w: (copy) copy	w: (no) no
  *		x: (no) no	x: (no) yes	x: (no) yes	x: (yes) yes
@@ -252,6 +253,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
 	if (vma->vm_file)
 		fput(vma->vm_file);
 	mpol_put(vma_policy(vma));
+	uksm_remove_vma(vma);
 	kmem_cache_free(vm_area_cachep, vma);
 	return next;
 }
@@ -707,9 +709,16 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start,
 	long adjust_next = 0;
 	int remove_next = 0;
 
+/*
+ * to avoid deadlock, ksm_remove_vma must be done before any spin_lock is
+ * acquired
+ */
+	uksm_remove_vma(vma);
+
 	if (next && !insert) {
 		struct vm_area_struct *exporter = NULL;
 
+		uksm_remove_vma(next);
 		if (end >= next->vm_end) {
 			/*
 			 * vma expands, overlapping all the next, and
@@ -803,6 +812,7 @@ again:			remove_next = 1 + (end > next->vm_end);
 		end_changed = true;
 	}
 	vma->vm_pgoff = pgoff;
+
 	if (adjust_next) {
 		next->vm_start += adjust_next << PAGE_SHIFT;
 		next->vm_pgoff += adjust_next;
@@ -873,16 +883,22 @@ again:			remove_next = 1 + (end > next->vm_end);
 		 * up the code too much to do both in one go.
 		 */
 		next = vma->vm_next;
-		if (remove_next == 2)
+		if (remove_next == 2) {
+			uksm_remove_vma(next);
 			goto again;
-		else if (next)
+		} else if (next) {
 			vma_gap_update(next);
-		else
+		} else {
 			mm->highest_vm_end = end;
+		}
+	} else {
+		if (next && !insert)
+			uksm_vma_add_new(next);
 	}
 	if (insert && file)
 		uprobe_mmap(insert);
 
+	uksm_vma_add_new(vma);
 	validate_mm(mm);
 
 	return 0;
@@ -1256,6 +1272,9 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) |
 			mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
 
+	/* If uksm is enabled, we add VM_MERGABLE to new VMAs. */
+	uksm_vm_flags_mod(&vm_flags);
+
 	if (flags & MAP_LOCKED)
 		if (!can_do_mlock())
 			return -EPERM;
@@ -1602,6 +1621,7 @@ munmap_back:
 
 	vma_link(mm, vma, prev, rb_link, rb_parent);
 	file = vma->vm_file;
+	uksm_vma_add_new(vma);
 
 	/* Once vma denies write, undo our temporary denial count */
 	if (correct_wcount)
@@ -1633,6 +1653,7 @@ unmap_and_free_vma:
 	unmap_region(mm, vma, prev, vma->vm_start, vma->vm_end);
 	charged = 0;
 free_vma:
+	uksm_remove_vma(vma);
 	kmem_cache_free(vm_area_cachep, vma);
 unacct_error:
 	if (charged)
@@ -1881,7 +1902,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	info.align_mask = 0;
 	return vm_unmapped_area(&info);
 }
-#endif	
+#endif
 
 void arch_unmap_area(struct mm_struct *mm, unsigned long addr)
 {
@@ -2462,6 +2483,8 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma,
 	else
 		err = vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new);
 
+	uksm_vma_add_new(new);
+
 	/* Success. */
 	if (!err)
 		return 0;
@@ -2658,6 +2681,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
 		return addr;
 
 	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
+	uksm_vm_flags_mod(&flags);
 
 	error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
 	if (error & ~PAGE_MASK)
@@ -2725,6 +2749,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
 	vma->vm_flags = flags;
 	vma->vm_page_prot = vm_get_page_prot(flags);
 	vma_link(mm, vma, prev, rb_link, rb_parent);
+	uksm_vma_add_new(vma);
 out:
 	perf_event_mmap(vma);
 	mm->total_vm += len >> PAGE_SHIFT;
@@ -2759,6 +2784,12 @@ void exit_mmap(struct mm_struct *mm)
 	/* mm's last user has gone, and its about to be pulled down */
 	mmu_notifier_release(mm);
 
+	/*
+	 * Taking write lock on mmap_sem does not harm others,
+	 * but it's crucial for uksm to avoid races.
+	 */
+	down_write(&mm->mmap_sem);
+
 	if (mm->locked_vm) {
 		vma = mm->mmap;
 		while (vma) {
@@ -2795,6 +2826,11 @@ void exit_mmap(struct mm_struct *mm)
 	}
 	vm_unacct_memory(nr_accounted);
 
+	mm->mmap = NULL;
+	mm->mm_rb = RB_ROOT;
+	mm->mmap_cache = NULL;
+	up_write(&mm->mmap_sem);
+
 	WARN_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT);
 }
 
@@ -2906,6 +2942,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap,
 				new_vma->vm_ops->open(new_vma);
 			vma_link(mm, new_vma, prev, rb_link, rb_parent);
 			*need_rmap_locks = false;
+			uksm_vma_add_new(new_vma);
 		}
 	}
 	return new_vma;
@@ -3007,10 +3044,10 @@ int install_special_mapping(struct mm_struct *mm,
 	ret = insert_vm_struct(mm, vma);
 	if (ret)
 		goto out;
-
 	mm->total_vm += len >> PAGE_SHIFT;
 
 	perf_event_mmap(vma);
+	uksm_vma_add_new(vma);
 
 	return 0;