1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
From: Felix Fietkau <nbd@nbd.name>
Subject: jffs2: use .rename2 and add RENAME_WHITEOUT support
It is required for renames on overlayfs
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -614,8 +614,8 @@ static int jffs2_rmdir (struct inode *di
return ret;
}
-static int jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i,
- struct dentry *dentry, umode_t mode, dev_t rdev)
+static int __jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i,
+ struct dentry *dentry, umode_t mode, dev_t rdev, bool whiteout)
{
struct jffs2_inode_info *f, *dir_f;
struct jffs2_sb_info *c;
@@ -754,7 +754,11 @@ static int jffs2_mknod (struct user_name
mutex_unlock(&dir_f->sem);
jffs2_complete_reservation(c);
- d_instantiate_new(dentry, inode);
+ if (!whiteout)
+ d_instantiate_new(dentry, inode);
+ else
+ unlock_new_inode(inode);
+
return 0;
fail:
@@ -762,6 +766,19 @@ static int jffs2_mknod (struct user_name
return ret;
}
+static int jffs2_mknod (struct user_namespace *mnt_userns, struct inode *dir_i,
+ struct dentry *dentry, umode_t mode, dev_t rdev)
+{
+ return __jffs2_mknod(mnt_userns, dir_i, dentry, mode, rdev, false);
+}
+
+static int jffs2_whiteout (struct user_namespace *mnt_userns, struct inode *old_dir,
+ struct dentry *old_dentry)
+{
+ return __jffs2_mknod(mnt_userns, old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE,
+ WHITEOUT_DEV, true);
+}
+
static int jffs2_rename (struct user_namespace *mnt_userns,
struct inode *old_dir_i, struct dentry *old_dentry,
struct inode *new_dir_i, struct dentry *new_dentry,
@@ -773,7 +790,7 @@ static int jffs2_rename (struct user_nam
uint8_t type;
uint32_t now;
- if (flags & ~RENAME_NOREPLACE)
+ if (flags & ~(RENAME_NOREPLACE|RENAME_WHITEOUT))
return -EINVAL;
/* The VFS will check for us and prevent trying to rename a
@@ -839,9 +856,14 @@ static int jffs2_rename (struct user_nam
if (d_is_dir(old_dentry) && !victim_f)
inc_nlink(new_dir_i);
- /* Unlink the original */
- ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
- old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
+ if (flags & RENAME_WHITEOUT)
+ /* Replace with whiteout */
+ ret = jffs2_whiteout(mnt_userns, old_dir_i, old_dentry);
+ else
+ /* Unlink the original */
+ ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
+ old_dentry->d_name.name,
+ old_dentry->d_name.len, NULL, now);
/* We don't touch inode->i_nlink */
|
