target/linux/generic/pending-5.15/140-jffs2-use-.rename2-and-add-RENAME_WHITEOUT-support.patch

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