Add AUFS to 4.1.13 by hand, patch doesn't apply cleanly

MAINTAINERS

@@ -1880,6 +1880,19 @@ F:	include/linux/audit.h
 F:	include/uapi/linux/audit.h
 F:	kernel/audit*
 
+AUFS (advanced multi layered unification filesystem) FILESYSTEM
+M:	"J. R. Okajima" <hooanon05g@gmail.com>
+L:	linux-unionfs@vger.kernel.org
+L:	aufs-users@lists.sourceforge.net (members only)
+W:	http://aufs.sourceforge.net
+T:	git://github.com/sfjro/aufs4-linux.git
+S:	Supported
+F:	Documentation/filesystems/aufs/
+F:	Documentation/ABI/testing/debugfs-aufs
+F:	Documentation/ABI/testing/sysfs-aufs
+F:	fs/aufs/
+F:	include/uapi/linux/aufs_type.h
+
 AUXILIARY DISPLAY DRIVERS
 M:	Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
 W:	http://miguelojeda.es/auxdisplay.htm

drivers/block/loop.c

@@ -538,6 +538,24 @@ static inline int is_loop_device(struct file *file)
 	return i && S_ISBLK(i->i_mode) && MAJOR(i->i_rdev) == LOOP_MAJOR;
 }
 
+/*
+ * for AUFS
+ * no get/put for file.
+ */
+struct file *loop_backing_file(struct super_block *sb)
+{
+	struct file *ret;
+	struct loop_device *l;
+
+	ret = NULL;
+	if (MAJOR(sb->s_dev) == LOOP_MAJOR) {
+		l = sb->s_bdev->bd_disk->private_data;
+		ret = l->lo_backing_file;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(loop_backing_file);
+
 /* loop sysfs attributes */
 
 static ssize_t loop_attr_show(struct device *dev, char *page,

fs/Kconfig

@@ -218,6 +218,7 @@ source "fs/pstore/Kconfig"
 source "fs/sysv/Kconfig"
 source "fs/ufs/Kconfig"
 source "fs/exofs/Kconfig"
+source "fs/aufs/Kconfig"
 
 endif # MISC_FILESYSTEMS
 

fs/Makefile

@@ -127,3 +127,4 @@ obj-y				+= exofs/ # Multiple modules
 obj-$(CONFIG_CEPH_FS)		+= ceph/
 obj-$(CONFIG_PSTORE)		+= pstore/
 obj-$(CONFIG_EFIVAR_FS)		+= efivarfs/
+obj-$(CONFIG_AUFS_FS)           += aufs/

fs/buffer.c

@@ -2450,7 +2450,7 @@ int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
 	 * Update file times before taking page lock. We may end up failing the
 	 * fault so this update may be superfluous but who really cares...
 	 */
-	file_update_time(vma->vm_file);
+	vma_file_update_time(vma);
 
 	ret = __block_page_mkwrite(vma, vmf, get_block);
 	sb_end_pagefault(sb);

fs/dcache.c

@@ -1167,7 +1167,7 @@ enum d_walk_ret {
  *
  * The @enter() and @finish() callbacks are called with d_lock held.
  */
-static void d_walk(struct dentry *parent, void *data,
+void d_walk(struct dentry *parent, void *data,
 		   enum d_walk_ret (*enter)(void *, struct dentry *),
 		   void (*finish)(void *))
 {
@@ -1272,6 +1272,7 @@ static void d_walk(struct dentry *parent, void *data,
 	seq = 1;
 	goto again;
 }
+EXPORT_SYMBOL(d_walk);
 
 /*
  * Search for at least 1 mount point in the dentry's subdirs.

fs/file_table.c

@@ -147,6 +147,7 @@ struct file *get_empty_filp(void)
 	}
 	return ERR_PTR(-ENFILE);
 }
+EXPORT_SYMBOL(get_empty_filp);
 
 /**
  * alloc_file - allocate and initialize a 'struct file'
@@ -308,6 +309,7 @@ void put_filp(struct file *file)
 		file_free(file);
 	}
 }
+EXPORT_SYMBOL(put_filp);
 
 void __init files_init(unsigned long mempages)
 { 

fs/inode.c

@@ -58,6 +58,7 @@ static struct hlist_head *inode_hashtable __read_mostly;
 static __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_hash_lock);
 
 __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_sb_list_lock);
+EXPORT_SYMBOL(inode_sb_list_lock);
 
 /*
  * Empty aops. Can be used for the cases where the user does not

fs/namespace.c

@@ -463,6 +463,7 @@ void __mnt_drop_write(struct vfsmount *mnt)
 	mnt_dec_writers(real_mount(mnt));
 	preempt_enable();
 }
+EXPORT_SYMBOL_GPL(__mnt_drop_write);
 
 /**
  * mnt_drop_write - give up write access to a mount
@@ -1792,6 +1793,7 @@ int iterate_mounts(int (*f)(struct vfsmount *, void *), void *arg,
 	}
 	return 0;
 }
+EXPORT_SYMBOL(iterate_mounts);
 
 static void cleanup_group_ids(struct mount *mnt, struct mount *end)
 {

fs/notify/group.c

@@ -22,6 +22,7 @@
 #include <linux/srcu.h>
 #include <linux/rculist.h>
 #include <linux/wait.h>
+#include <linux/module.h>
 
 #include <linux/fsnotify_backend.h>
 #include "fsnotify.h"
@@ -72,6 +73,7 @@ void fsnotify_get_group(struct fsnotify_group *group)
 {
 	atomic_inc(&group->refcnt);
 }
+EXPORT_SYMBOL(fsnotify_get_group);
 
 /*
  * Drop a reference to a group.  Free it if it's through.
@@ -81,6 +83,7 @@ void fsnotify_put_group(struct fsnotify_group *group)
 	if (atomic_dec_and_test(&group->refcnt))
 		fsnotify_final_destroy_group(group);
 }
+EXPORT_SYMBOL(fsnotify_put_group);
 
 /*
  * Create a new fsnotify_group and hold a reference for the group returned.
@@ -109,6 +112,7 @@ struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
 
 	return group;
 }
+EXPORT_SYMBOL(fsnotify_alloc_group);
 
 int fsnotify_fasync(int fd, struct file *file, int on)
 {

fs/notify/mark.c

@@ -109,6 +109,7 @@ void fsnotify_put_mark(struct fsnotify_mark *mark)
 		mark->free_mark(mark);
 	}
 }
+EXPORT_SYMBOL(fsnotify_put_mark);
 
 /* Calculate mask of events for a list of marks */
 u32 fsnotify_recalc_mask(struct hlist_head *head)
@@ -202,6 +203,7 @@ void fsnotify_destroy_mark(struct fsnotify_mark *mark,
 	fsnotify_destroy_mark_locked(mark, group);
 	mutex_unlock(&group->mark_mutex);
 }
+EXPORT_SYMBOL(fsnotify_destroy_mark);
 
 /*
  * Destroy all marks in the given list. The marks must be already detached from
@@ -376,6 +378,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
 
 	return ret;
 }
+EXPORT_SYMBOL(fsnotify_add_mark);
 
 int fsnotify_add_mark(struct fsnotify_mark *mark, struct fsnotify_group *group,
 		      struct inode *inode, struct vfsmount *mnt, int allow_dups)
@@ -475,6 +478,7 @@ void fsnotify_init_mark(struct fsnotify_mark *mark,
 	atomic_set(&mark->refcnt, 1);
 	mark->free_mark = free_mark;
 }
+EXPORT_SYMBOL(fsnotify_init_mark);
 
 static int fsnotify_mark_destroy(void *ignored)
 {

fs/open.c

@@ -62,6 +62,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 	mutex_unlock(&dentry->d_inode->i_mutex);
 	return ret;
 }
+EXPORT_SYMBOL(do_truncate);
 
 long vfs_truncate(struct path *path, loff_t length)
 {
@@ -676,6 +677,7 @@ int open_check_o_direct(struct file *f)
 	}
 	return 0;
 }
+EXPORT_SYMBOL(open_check_o_direct);
 
 static int do_dentry_open(struct file *f,
 			  struct inode *inode,

fs/proc/base.c

@@ -1744,7 +1744,7 @@ static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
 	down_read(&mm->mmap_sem);
 	vma = find_exact_vma(mm, vm_start, vm_end);
 	if (vma && vma->vm_file) {
-		*path = vma->vm_file->f_path;
+		*path = vma_pr_or_file(vma)->f_path;
 		path_get(path);
 		rc = 0;
 	}

fs/proc/nommu.c

@@ -45,7 +45,10 @@ static int nommu_region_show(struct seq_file *m, struct vm_region *region)
 	file = region->vm_file;
 
 	if (file) {
-		struct inode *inode = file_inode(region->vm_file);
+		struct inode *inode;
+
+		file = vmr_pr_or_file(region);
+		inode = file_inode(file);
 		dev = inode->i_sb->s_dev;
 		ino = inode->i_ino;
 	}

fs/proc/task_mmu.c

@@ -279,7 +279,10 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
 	const char *name = NULL;
 
 	if (file) {
-		struct inode *inode = file_inode(vma->vm_file);
+		struct inode *inode;
+
+		file = vma_pr_or_file(vma);
+		inode = file_inode(file);
 		dev = inode->i_sb->s_dev;
 		ino = inode->i_ino;
 		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
@@ -1479,7 +1482,7 @@ static int show_numa_map(struct seq_file *m, void *v, int is_pid)
 	struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
 	struct vm_area_struct *vma = v;
 	struct numa_maps *md = &numa_priv->md;
-	struct file *file = vma->vm_file;
+	struct file *file = vma_pr_or_file(vma);
 	struct mm_struct *mm = vma->vm_mm;
 	struct mm_walk walk = {
 		.hugetlb_entry = gather_hugetlb_stats,

fs/proc/task_nommu.c

@@ -160,7 +160,10 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma,
 	file = vma->vm_file;
 
 	if (file) {
-		struct inode *inode = file_inode(vma->vm_file);
+		struct inode *inode;
+
+		file = vma_pr_or_file(vma);
+		inode = file_inode(file);
 		dev = inode->i_sb->s_dev;
 		ino = inode->i_ino;
 		pgoff = (loff_t)vma->vm_pgoff << PAGE_SHIFT;

fs/read_write.c

@@ -494,6 +494,30 @@ ssize_t __vfs_write(struct file *file, const char __user *p, size_t count,
 }
 EXPORT_SYMBOL(__vfs_write);
 
+vfs_readf_t vfs_readf(struct file *file)
+{
+	const struct file_operations *fop = file->f_op;
+
+	if (fop->read)
+		return fop->read;
+	if (fop->read_iter)
+		return new_sync_read;
+	return ERR_PTR(-ENOSYS);
+}
+EXPORT_SYMBOL(vfs_readf);
+
+vfs_writef_t vfs_writef(struct file *file)
+{
+	const struct file_operations *fop = file->f_op;
+
+	if (fop->write)
+		return fop->write;
+	if (fop->write_iter)
+		return new_sync_write;
+	return ERR_PTR(-ENOSYS);
+}
+EXPORT_SYMBOL(vfs_writef);
+
 ssize_t __kernel_write(struct file *file, const char *buf, size_t count, loff_t *pos)
 {
 	mm_segment_t old_fs;

fs/splice.c

@@ -1101,8 +1101,8 @@ EXPORT_SYMBOL(generic_splice_sendpage);
 /*
  * Attempt to initiate a splice from pipe to file.
  */
-static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
-			   loff_t *ppos, size_t len, unsigned int flags)
+long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
+		    loff_t *ppos, size_t len, unsigned int flags)
 {
 	ssize_t (*splice_write)(struct pipe_inode_info *, struct file *,
 				loff_t *, size_t, unsigned int);
@@ -1114,13 +1114,14 @@ static long do_splice_from(struct pipe_inode_info *pipe, struct file *out,
 
 	return splice_write(pipe, out, ppos, len, flags);
 }
+EXPORT_SYMBOL(do_splice_from);
 
 /*
  * Attempt to initiate a splice from a file to a pipe.
  */
-static long do_splice_to(struct file *in, loff_t *ppos,
-			 struct pipe_inode_info *pipe, size_t len,
-			 unsigned int flags)
+long do_splice_to(struct file *in, loff_t *ppos,
+		  struct pipe_inode_info *pipe, size_t len,
+		  unsigned int flags)
 {
 	ssize_t (*splice_read)(struct file *, loff_t *,
 			       struct pipe_inode_info *, size_t, unsigned int);
@@ -1140,6 +1141,7 @@ static long do_splice_to(struct file *in, loff_t *ppos,
 
 	return splice_read(in, ppos, pipe, len, flags);
 }
+EXPORT_SYMBOL(do_splice_to);
 
 /**
  * splice_direct_to_actor - splices data directly between two non-pipes

fs/xattr.c

@@ -207,6 +207,7 @@ vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
 	*xattr_value = value;
 	return error;
 }
+EXPORT_SYMBOL(vfs_getxattr_alloc);
 
 /* Compare an extended attribute value with the given value */
 int vfs_xattr_cmp(struct dentry *dentry, const char *xattr_name,

include/linux/file.h

@@ -19,6 +19,7 @@ struct dentry;
 struct path;
 extern struct file *alloc_file(struct path *, fmode_t mode,
 	const struct file_operations *fop);
+extern struct file *get_empty_filp(void);
 
 static inline void fput_light(struct file *file, int fput_needed)
 {

include/linux/fs.h

@@ -1663,6 +1663,12 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
 			      struct iovec *fast_pointer,
 			      struct iovec **ret_pointer);
 
+typedef ssize_t (*vfs_readf_t)(struct file *, char __user *, size_t, loff_t *);
+typedef ssize_t (*vfs_writef_t)(struct file *, const char __user *, size_t,
+				loff_t *);
+vfs_readf_t vfs_readf(struct file *file);
+vfs_writef_t vfs_writef(struct file *file);
+
 extern ssize_t __vfs_read(struct file *, char __user *, size_t, loff_t *);
 extern ssize_t __vfs_write(struct file *, const char __user *, size_t, loff_t *);
 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);

include/linux/mm.h

@@ -1200,6 +1200,28 @@ static inline int fixup_user_fault(struct task_struct *tsk,
 }
 #endif
 
+extern void vma_do_file_update_time(struct vm_area_struct *, const char[], int);
+extern struct file *vma_do_pr_or_file(struct vm_area_struct *, const char[],
+				      int);
+extern void vma_do_get_file(struct vm_area_struct *, const char[], int);
+extern void vma_do_fput(struct vm_area_struct *, const char[], int);
+
+#define vma_file_update_time(vma)	vma_do_file_update_time(vma, __func__, \
+								__LINE__)
+#define vma_pr_or_file(vma)		vma_do_pr_or_file(vma, __func__, \
+							  __LINE__)
+#define vma_get_file(vma)		vma_do_get_file(vma, __func__, __LINE__)
+#define vma_fput(vma)			vma_do_fput(vma, __func__, __LINE__)
+
+#ifndef CONFIG_MMU
+extern struct file *vmr_do_pr_or_file(struct vm_region *, const char[], int);
+extern void vmr_do_fput(struct vm_region *, const char[], int);
+
+#define vmr_pr_or_file(region)		vmr_do_pr_or_file(region, __func__, \
+							  __LINE__)
+#define vmr_fput(region)		vmr_do_fput(region, __func__, __LINE__)
+#endif /* !CONFIG_MMU */
+
 extern int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write);
 extern int access_remote_vm(struct mm_struct *mm, unsigned long addr,
 		void *buf, int len, int write);

include/linux/mm_types.h

@@ -232,6 +232,7 @@ struct vm_region {
 	unsigned long	vm_top;		/* region allocated to here */
 	unsigned long	vm_pgoff;	/* the offset in vm_file corresponding to vm_start */
 	struct file	*vm_file;	/* the backing file or NULL */
+	struct file	*vm_prfile;	/* the virtual backing file or NULL */
 
 	int		vm_usage;	/* region usage count (access under nommu_region_sem) */
 	bool		vm_icache_flushed : 1; /* true if the icache has been flushed for
@@ -296,6 +297,7 @@ struct vm_area_struct {
 	unsigned long vm_pgoff;		/* Offset (within vm_file) in PAGE_SIZE
 					   units, *not* PAGE_CACHE_SIZE */
 	struct file * vm_file;		/* File we map to (can be NULL). */
+	struct file *vm_prfile;		/* shadow of vm_file */
 	void * vm_private_data;		/* was vm_pte (shared mem) */
 
 #ifndef CONFIG_MMU