| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | From: Felix Fietkau <nbd@nbd.name> |
| 2 | Subject: jffs2: add RENAME_EXCHANGE support |
| 3 | |
| 4 | Signed-off-by: Felix Fietkau <nbd@nbd.name> |
| 5 | --- |
| 6 | |
| 7 | --- a/fs/jffs2/dir.c |
| 8 | +++ b/fs/jffs2/dir.c |
| 9 | @@ -781,18 +781,31 @@ static int jffs2_rename (struct inode *o |
| 10 | int ret; |
| 11 | struct jffs2_sb_info *c = JFFS2_SB_INFO(old_dir_i->i_sb); |
| 12 | struct jffs2_inode_info *victim_f = NULL; |
| 13 | + struct inode *fst_inode = d_inode(old_dentry); |
| 14 | + struct inode *snd_inode = d_inode(new_dentry); |
| 15 | uint8_t type; |
| 16 | uint32_t now; |
| 17 | |
| 18 | - if (flags & ~(RENAME_NOREPLACE|RENAME_WHITEOUT)) |
| 19 | + if (flags & ~(RENAME_NOREPLACE|RENAME_WHITEOUT|RENAME_EXCHANGE)) |
| 20 | return -EINVAL; |
| 21 | |
| 22 | + if ((flags & RENAME_EXCHANGE) && (old_dir_i != new_dir_i)) { |
| 23 | + if (S_ISDIR(fst_inode->i_mode) && !S_ISDIR(snd_inode->i_mode)) { |
| 24 | + inc_nlink(new_dir_i); |
| 25 | + drop_nlink(old_dir_i); |
| 26 | + } |
| 27 | + else if (!S_ISDIR(fst_inode->i_mode) && S_ISDIR(snd_inode->i_mode)) { |
| 28 | + drop_nlink(new_dir_i); |
| 29 | + inc_nlink(old_dir_i); |
| 30 | + } |
| 31 | + } |
| 32 | + |
| 33 | /* The VFS will check for us and prevent trying to rename a |
| 34 | * file over a directory and vice versa, but if it's a directory, |
| 35 | * the VFS can't check whether the victim is empty. The filesystem |
| 36 | * needs to do that for itself. |
| 37 | */ |
| 38 | - if (d_really_is_positive(new_dentry)) { |
| 39 | + if (d_really_is_positive(new_dentry) && !(flags & RENAME_EXCHANGE)) { |
| 40 | victim_f = JFFS2_INODE_INFO(d_inode(new_dentry)); |
| 41 | if (d_is_dir(new_dentry)) { |
| 42 | struct jffs2_full_dirent *fd; |
| 43 | @@ -827,7 +840,7 @@ static int jffs2_rename (struct inode *o |
| 44 | if (ret) |
| 45 | return ret; |
| 46 | |
| 47 | - if (victim_f) { |
| 48 | + if (victim_f && !(flags & RENAME_EXCHANGE)) { |
| 49 | /* There was a victim. Kill it off nicely */ |
| 50 | if (d_is_dir(new_dentry)) |
| 51 | clear_nlink(d_inode(new_dentry)); |
| 52 | @@ -853,6 +866,12 @@ static int jffs2_rename (struct inode *o |
| 53 | if (flags & RENAME_WHITEOUT) |
| 54 | /* Replace with whiteout */ |
| 55 | ret = jffs2_whiteout(old_dir_i, old_dentry); |
| 56 | + else if (flags & RENAME_EXCHANGE) |
| 57 | + /* Replace the original */ |
| 58 | + ret = jffs2_do_link(c, JFFS2_INODE_INFO(old_dir_i), |
| 59 | + d_inode(new_dentry)->i_ino, type, |
| 60 | + old_dentry->d_name.name, old_dentry->d_name.len, |
| 61 | + now); |
| 62 | else |
| 63 | /* Unlink the original */ |
| 64 | ret = jffs2_do_unlink(c, JFFS2_INODE_INFO(old_dir_i), |
| 65 | @@ -884,7 +903,7 @@ static int jffs2_rename (struct inode *o |
| 66 | return ret; |
| 67 | } |
| 68 | |
| 69 | - if (d_is_dir(old_dentry)) |
| 70 | + if (d_is_dir(old_dentry) && !(flags & RENAME_EXCHANGE)) |
| 71 | drop_nlink(old_dir_i); |
| 72 | |
| 73 | new_dir_i->i_mtime = new_dir_i->i_ctime = old_dir_i->i_mtime = old_dir_i->i_ctime = ITIME(now); |