[PATCH v3 05/20] ext4 fast_commit: make use of name_snapshot primitives

Al Viro
2025-01-23T01:46:45Z

... rather than open-coding them. As a bonus, that avoids the pointless
work with extra allocations, etc. for long names.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/ext4/fast_commit.c | 29 +++++------------------------
fs/ext4/fast_commit.h | 3 +--
2 files changed, 6 insertions(+), 26 deletions(-)

diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index 26c4fc37edcf..da4263a14a20 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -322,9 +322,7 @@ void ext4_fc_del(struct inode *inode)
WARN_ON(!list_empty(&ei->i_fc_dilist));
spin_unlock(&sbi->s_fc_lock);

- if (fc_dentry->fcd_name.name &&
- fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
- kfree(fc_dentry->fcd_name.name);
+ release_dentry_name_snapshot(&fc_dentry->fcd_name);
kmem_cache_free(ext4_fc_dentry_cachep, fc_dentry);

return;
@@ -449,22 +447,7 @@ static int __track_dentry_update(handle_t *handle, struct inode *inode,
node->fcd_op = dentry_update->op;
node->fcd_parent = dir->i_ino;
node->fcd_ino = inode->i_ino;
- if (dentry->d_name.len > DNAME_INLINE_LEN) {
- node->fcd_name.name = kmalloc(dentry->d_name.len, GFP_NOFS);
- if (!node->fcd_name.name) {
- kmem_cache_free(ext4_fc_dentry_cachep, node);
- ext4_fc_mark_ineligible(sb, EXT4_FC_REASON_NOMEM, handle);
- mutex_lock(&ei->i_fc_lock);
- return -ENOMEM;
- }
- memcpy((u8 *)node->fcd_name.name, dentry->d_name.name,
- dentry->d_name.len);
- } else {
- memcpy(node->fcd_iname, dentry->d_name.name,
- dentry->d_name.len);
- node->fcd_name.name = node->fcd_iname;
- }
- node->fcd_name.len = dentry->d_name.len;
+ take_dentry_name_snapshot(&node->fcd_name, dentry);
INIT_LIST_HEAD(&node->fcd_dilist);
spin_lock(&sbi->s_fc_lock);
if (sbi->s_journal->j_flags & JBD2_FULL_COMMIT_ONGOING ||
@@ -832,7 +815,7 @@ static bool ext4_fc_add_dentry_tlv(struct super_block *sb, u32 *crc,
{
struct ext4_fc_dentry_info fcd;
struct ext4_fc_tl tl;
- int dlen = fc_dentry->fcd_name.len;
+ int dlen = fc_dentry->fcd_name.name.len;
u8 *dst = ext4_fc_reserve_space(sb,
EXT4_FC_TAG_BASE_LEN + sizeof(fcd) + dlen, crc);

@@ -847,7 +830,7 @@ static bool ext4_fc_add_dentry_tlv(struct super_block *sb, u32 *crc,
dst += EXT4_FC_TAG_BASE_LEN;
memcpy(dst, &fcd, sizeof(fcd));
dst += sizeof(fcd);
- memcpy(dst, fc_dentry->fcd_name.name, dlen);
+ memcpy(dst, fc_dentry->fcd_name.name.name, dlen);

return true;
}
@@ -1328,9 +1311,7 @@ static void ext4_fc_cleanup(journal_t *journal, int full, tid_t tid)
list_del_init(&fc_dentry->fcd_dilist);
spin_unlock(&sbi->s_fc_lock);

- if (fc_dentry->fcd_name.name &&
- fc_dentry->fcd_name.len > DNAME_INLINE_LEN)
- kfree(fc_dentry->fcd_name.name);
+ release_dentry_name_snapshot(&fc_dentry->fcd_name);
kmem_cache_free(ext4_fc_dentry_cachep, fc_dentry);
spin_lock(&sbi->s_fc_lock);
}
diff --git a/fs/ext4/fast_commit.h b/fs/ext4/fast_commit.h
index 2fadb2c4780c..3bd534e4dbbf 100644
--- a/fs/ext4/fast_commit.h
+++ b/fs/ext4/fast_commit.h
@@ -109,8 +109,7 @@ struct ext4_fc_dentry_update {
int fcd_op; /* Type of update create / unlink / link */
int fcd_parent; /* Parent inode number */
int fcd_ino; /* Inode number */
- struct qstr fcd_name; /* Dirent name */
- unsigned char fcd_iname[DNAME_INLINE_LEN]; /* Dirent name string */
+ struct name_snapshot fcd_name; /* Dirent name */
struct list_head fcd_list;
struct list_head fcd_dilist;
};
--
2.39.5