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 @@ -609,7 +609,8 @@ static int jffs2_rmdir (struct inode *di
  12         return ret;
  13  }
  14
  15 -static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode, dev_t rdev)
  16 +static int __jffs2_mknod (struct inode *dir_i, struct dentry *dentry,
  17 +                         umode_t mode, dev_t rdev, bool whiteout)
  18  {
  19         struct jffs2_inode_info *f, *dir_f;
  20         struct jffs2_sb_info *c;
  21 @@ -748,7 +749,11 @@ static int jffs2_mknod (struct inode *di
  22         mutex_unlock(&dir_f->sem);
  23         jffs2_complete_reservation(c);
  24
  25 -       d_instantiate_new(dentry, inode);
  26 +       if (!whiteout)
  27 +               d_instantiate_new(dentry, inode);
  28 +       else
  29 +               unlock_new_inode(inode);
  30 +
  31         return 0;
  32
  33   fail:
  34 @@ -756,6 +761,17 @@ static int jffs2_mknod (struct inode *di
  35         return ret;
  36  }
  37
  38 +static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode, dev_t rdev)
  39 +{
  40 +       return __jffs2_mknod(dir_i, dentry, mode, rdev, false);
  41 +}
  42 +
  43 +static int jffs2_whiteout (struct inode *old_dir, struct dentry *old_dentry)
  44 +{
  45 +       return __jffs2_mknod(old_dir, old_dentry, S_IFCHR | WHITEOUT_MODE,
  46 +                            WHITEOUT_DEV, true);
  47 +}
  48 +
  49  static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry,
  50                          struct inode *new_dir_i, struct dentry *new_dentry,
  51                          unsigned int flags)
  52 @@ -766,7 +782,7 @@ static int jffs2_rename (struct inode *o
  53         uint8_t type;
  54         uint32_t now;
  55
  56 -       if (flags & ~RENAME_NOREPLACE)
  57 +       if (flags & ~(RENAME_NOREPLACE|RENAME_WHITEOUT))
  58                 return -EINVAL;
  59
  60         /* The VFS will check for us and prevent trying to rename a
  61 @@ -832,9 +848,14 @@ static int jffs2_rename (struct inode *o
  62         if (d_is_dir(old_dentry) && !victim_f)
  63                 inc_nlink(new_dir_i);
  64
  65 -       /* Unlink the original */
  66 -       ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
  67 -                             old_dentry->d_name.name, old_dentry->d_name.len, NULL, now);
  68 +       if (flags & RENAME_WHITEOUT)
  69 +               /* Replace with whiteout */
  70 +               ret = jffs2_whiteout(old_dir_i, old_dentry);
  71 +       else
  72 +               /* Unlink the original */
  73 +               ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i),
  74 +                                     old_dentry->d_name.name,
  75 +                                     old_dentry->d_name.len, NULL, now);
  76
  77         /* We don't touch inode->i_nlink */
  78