Viewing: ext4-dirdata-lustre-compat.patch
commit 409935cc7094bf0d98b392d8ddc9a016f02749eb
Author: Artem Blagodarenko <ablagodarenko@thelustrecollective.com>
Date: Mon Jan 19 09:37:24 2026 +0300
LU-19847 ldiskfs: dirent and fscrypt+case_insensitive
EXT4 occupies space in dirent just after the name with
a hash for simultaneous fscrypt and casefold support.
It was discussed with the EXT4 community that it is
possible to move the hash to dirdata. It could be the
second (or third, if 64-bit inode count) user of
dirdata.
At the same time, the hash placed after the file name
should also be supported.
This patch makes LDISKFS ready for such a hash present
in both variants. While it is not currently possible
to enable fscrypt + case_insensitive on LDISKFS, it is
useful to verify that LUFID works well with such code.
fscrypt + case_insensitive support with dirdata
enabled is checked in a special xfstest sent to EXT4
with the dirdata patch.
Test-Parameters: clientdistro=el10.0 serverdistro=el10.0
Test-Parameters: clientdistro=el10.1 serverdistro=el10.1
Signed-off-by: Artem Blagodarenko <ablagodarenko@thelustrecollective.com>
Change-Id: Ia9874396037a24b494dd3cfa7208e10a366f5eb3
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/64439
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@thelustrecollective.com>
---
Patch 3 of 3: ext4-dirdata-lustre-compat.patch
---
fs/ext4/ext4.h | 19 ++++++++++++++++++
fs/ext4/namei.c | 51 ++++++++++++++++++++++++++++++++++++++++++++++---
2 files changed, 67 insertions(+), 3 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1184,6 +1184,7 @@ struct ext4_inode_info {
__u32 i_csum_seed;
kprojid_t i_projid;
+ void *i_dirdata;
#ifdef CONFIG_FS_ENCRYPTION
struct fscrypt_inode_info *i_crypt_info;
@@ -2503,6 +2504,13 @@ struct ext4_dir_entry_tail {
#define EXT4_DIRENT_INO64 0x20
#define EXT4_DIRENT_CFHASH 0x40
+#define EXT4_LUFID_MAGIC 0xAD200907UL
+struct ext4_dentry_param {
+ __u32 edp_magic; /* EXT4_LUFID_MAGIC */
+ char edp_len; /* size of edp_data in bytes */
+ char edp_data[]; /* packed array of data */
+} __packed;
+
struct ext4_dirent_data_header {
/* length of this header + the whole data blob */
__u8 ddh_length;
@@ -2513,6 +2521,17 @@ struct ext4_dirent_hash {
struct ext4_dir_entry_hash dh_hash;
} __packed;
+static inline unsigned char *ext4_dentry_get_data(struct super_block *sb,
+ struct ext4_dentry_param *p)
+{
+ if (!ext4_has_feature_dirdata(sb))
+ return NULL;
+ if (p && p->edp_magic == EXT4_LUFID_MAGIC)
+ return &p->edp_len;
+ else
+ return NULL;
+}
+
#define EXT4_FT_DIR_CSUM 0xDE
/*
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2233,6 +2233,8 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
if (ext4_has_feature_metadata_csum(inode->i_sb))
csum_size = sizeof(struct ext4_dir_entry_tail);
+ data = ext4_dentry_get_data(inode->i_sb, (struct ext4_dentry_param *)
+ EXT4_I(inode)->i_dirdata);
if (!de) {
if (data)
dlen = (*data) + 1;
@@ -2606,7 +2608,8 @@ static int ext4_update_dotdot(handle_t *handle, struct dentry *dentry,
dotdot_de->inode = cpu_to_le32(inode->i_ino);
- /* Deliver data any appropriate way here. Now it is NULL */
+ data = ext4_dentry_get_data(dir->i_sb,
+ (struct ext4_dentry_param *)dentry->d_fsdata);
if (data != NULL) {
dlen = *data + 1;
if (is_dx(dir)) {
@@ -2666,6 +2669,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
ext4_lblk_t block, blocks;
int csum_size = 0;
+ EXT4_I(inode)->i_dirdata = dentry->d_fsdata;
if (ext4_has_feature_metadata_csum(inode->i_sb))
csum_size = sizeof(struct ext4_dir_entry_tail);
@@ -3250,22 +3254,40 @@ static int _ext4_init_dirblock(handle_t *handle, struct inode *inode,
struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) bh->b_data;
size_t blocksize = bh->b_size;
int csum_size = 0, header_size;
+ int dot_reclen = 0;
if (ext4_has_feature_metadata_csum(inode->i_sb))
csum_size = sizeof(struct ext4_dir_entry_tail);
de->inode = cpu_to_le32(inode->i_ino);
de->name_len = 1;
- de->rec_len = ext4_rec_len_to_disk(ext4_dir_rec_len(de->name_len, NULL),
- blocksize);
memcpy(de->name, ".", 2);
ext4_set_de_type(inode->i_sb, de, S_IFDIR);
+ /* get packed fid data*/
+ data1 = ext4_dentry_get_data(inode->i_sb,
+ (struct ext4_dentry_param *) data1);
+ if (data1) {
+ de->name[1] = 0;
+ memcpy(&de->name[2], data1, *(char *) data1);
+ de->file_type |= EXT4_DIRENT_LUFID;
+ }
+ de->rec_len = cpu_to_le16(EXT4_DIR_ENTRY_LEN(de, NULL));
+
+ dot_reclen = cpu_to_le16(de->rec_len);
de = ext4_next_entry(de, blocksize);
de->inode = cpu_to_le32(parent_ino);
de->name_len = 2;
memcpy(de->name, "..", 3);
ext4_set_de_type(inode->i_sb, de, S_IFDIR);
+ data2 = ext4_dentry_get_data(inode->i_sb,
+ (struct ext4_dentry_param *) data2);
+ if (data2) {
+ de->name[2] = 0;
+ memcpy(&de->name[3], data2, *(char *) data2);
+ de->file_type |= EXT4_DIRENT_LUFID;
+ }
+
if (inline_buf) {
de->rec_len = ext4_rec_len_to_disk(
ext4_dir_entry_len(de, NULL),
@@ -3390,6 +3412,29 @@ out_retry:
return ERR_PTR(err);
}
+/* Initialize @inode as a subdirectory of @dir, and add the
+ * "." and ".." entries into the first directory block. */
+int ext4_add_dot_dotdot(handle_t *handle, struct inode *dir,
+ struct inode *inode,
+ const void *data1, const void *data2)
+{
+ int rc;
+
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ if (IS_DIRSYNC(dir))
+ ext4_handle_sync(handle);
+
+ inode->i_op = &ext4_dir_inode_operations;
+ inode->i_fop = &ext4_dir_operations;
+ rc = ext4_init_new_dir(handle, dir, inode, data1, data2);
+ if (!rc)
+ rc = ext4_mark_inode_dirty(handle, inode);
+ return rc;
+}
+EXPORT_SYMBOL(ext4_add_dot_dotdot);
+
/*
* routine to check that the specified directory is empty (for rmdir)
*/
--
2.53.0
