On Tue, Jul 02, 2019 at 05:29:23PM -0400, Theodore Ts'o wrote:
> Functions such as ext4_dirent_csum_verify() and ext4_dirent_csum_set()
> don't actually operate on a directory entry, but a directory block.
> And while they take a struct ext4_dir_entry *dirent as an argument, it
> had better be the first directory at the beginning of the direct
> block, or things will go very wrong.
>
> Rename the following functions so that things make more sense, and
> remove a lot of confusing casts along the way:
>
> ext4_dirent_csum_verify -> ext4_dirblock_csum_verify
> ext4_dirent_csum_set -> ext4_dirblock_csum_set
> ext4_dirent_csum -> ext4_dirblock_csum
> ext4_handle_dirty_dirent_node -> ext4_handle_dirty_dirblock
>
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Looks ok,
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
--D
> ---
> fs/ext4/dir.c | 3 +--
> fs/ext4/ext4.h | 9 ++++---
> fs/ext4/inline.c | 2 +-
> fs/ext4/namei.c | 62 ++++++++++++++++++++++--------------------------
> 4 files changed, 35 insertions(+), 41 deletions(-)
>
> diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
> index 3a77b7affd09..86054f31fe4d 100644
> --- a/fs/ext4/dir.c
> +++ b/fs/ext4/dir.c
> @@ -194,8 +194,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
>
> /* Check the checksum */
> if (!buffer_verified(bh) &&
> - !ext4_dirent_csum_verify(inode,
> - (struct ext4_dir_entry *)bh->b_data)) {
> + !ext4_dirblock_csum_verify(inode, bh)) {
> EXT4_ERROR_FILE(file, 0, "directory fails checksum "
> "at offset %llu",
> (unsigned long long)ctx->pos);
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 7215a2a2a0de..5b86df7ec326 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -2602,8 +2602,8 @@ extern int ext4_ext_migrate(struct inode *);
> extern int ext4_ind_migrate(struct inode *inode);
>
> /* namei.c */
> -extern int ext4_dirent_csum_verify(struct inode *inode,
> - struct ext4_dir_entry *dirent);
> +extern int ext4_dirblock_csum_verify(struct inode *inode,
> + struct buffer_head *bh);
> extern int ext4_orphan_add(handle_t *, struct inode *);
> extern int ext4_orphan_del(handle_t *, struct inode *);
> extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
> @@ -3149,9 +3149,8 @@ extern struct ext4_dir_entry_2 *ext4_init_dot_dotdot(struct inode *inode,
> unsigned int parent_ino, int dotdot_real_len);
> extern void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
> unsigned int blocksize);
> -extern int ext4_handle_dirty_dirent_node(handle_t *handle,
> - struct inode *inode,
> - struct buffer_head *bh);
> +extern int ext4_handle_dirty_dirblock(handle_t *handle, struct inode *inode,
> + struct buffer_head *bh);
> extern int ext4_ci_compare(const struct inode *parent,
> const struct qstr *fname,
> const struct qstr *entry, bool quick);
> diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
> index f73bc3925282..f19dd5a08d0d 100644
> --- a/fs/ext4/inline.c
> +++ b/fs/ext4/inline.c
> @@ -1164,7 +1164,7 @@ static int ext4_finish_convert_inline_dir(handle_t *handle,
> initialize_dirent_tail(t, inode->i_sb->s_blocksize);
> }
> set_buffer_uptodate(dir_block);
> - err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
> + err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
> if (err)
> return err;
> set_buffer_verified(dir_block);
> diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
> index 0cda080f3fd5..4f0bcbbcfe96 100644
> --- a/fs/ext4/namei.c
> +++ b/fs/ext4/namei.c
> @@ -163,7 +163,7 @@ static struct buffer_head *__ext4_read_dirblock(struct inode *inode,
> }
> }
> if (!is_dx_block) {
> - if (ext4_dirent_csum_verify(inode, dirent))
> + if (ext4_dirblock_csum_verify(inode, bh))
> set_buffer_verified(bh);
> else {
> ext4_error_inode(inode, func, line, block,
> @@ -304,17 +304,17 @@ void initialize_dirent_tail(struct ext4_dir_entry_tail *t,
>
> /* Walk through a dirent block to find a checksum "dirent" at the tail */
> static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
> - struct ext4_dir_entry *de)
> + struct buffer_head *bh)
> {
> struct ext4_dir_entry_tail *t;
>
> #ifdef PARANOID
> struct ext4_dir_entry *d, *top;
>
> - d = de;
> - top = (struct ext4_dir_entry *)(((void *)de) +
> + d = (struct ext4_dir_entry *)bh->b_data;
> + top = (struct ext4_dir_entry *)(bh->b_data +
> (EXT4_BLOCK_SIZE(inode->i_sb) -
> - sizeof(struct ext4_dir_entry_tail)));
> + sizeof(struct ext4_dir_entry_tail)));
> while (d < top && d->rec_len)
> d = (struct ext4_dir_entry *)(((void *)d) +
> le16_to_cpu(d->rec_len));
> @@ -324,7 +324,7 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
>
> t = (struct ext4_dir_entry_tail *)d;
> #else
> - t = EXT4_DIRENT_TAIL(de, EXT4_BLOCK_SIZE(inode->i_sb));
> + t = EXT4_DIRENT_TAIL(bh->b_data, EXT4_BLOCK_SIZE(inode->i_sb));
> #endif
>
> if (t->det_reserved_zero1 ||
> @@ -336,8 +336,7 @@ static struct ext4_dir_entry_tail *get_dirent_tail(struct inode *inode,
> return t;
> }
>
> -static __le32 ext4_dirent_csum(struct inode *inode,
> - struct ext4_dir_entry *dirent, int size)
> +static __le32 ext4_dirblock_csum(struct inode *inode, void *dirent, int size)
> {
> struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
> struct ext4_inode_info *ei = EXT4_I(inode);
> @@ -357,49 +356,49 @@ static void __warn_no_space_for_csum(struct inode *inode, const char *func,
> "No space for directory leaf checksum. Please run e2fsck -D.");
> }
>
> -int ext4_dirent_csum_verify(struct inode *inode, struct ext4_dir_entry *dirent)
> +int ext4_dirblock_csum_verify(struct inode *inode, struct buffer_head *bh)
> {
> struct ext4_dir_entry_tail *t;
>
> if (!ext4_has_metadata_csum(inode->i_sb))
> return 1;
>
> - t = get_dirent_tail(inode, dirent);
> + t = get_dirent_tail(inode, bh);
> if (!t) {
> warn_no_space_for_csum(inode);
> return 0;
> }
>
> - if (t->det_checksum != ext4_dirent_csum(inode, dirent,
> - (void *)t - (void *)dirent))
> + if (t->det_checksum != ext4_dirblock_csum(inode, bh->b_data,
> + (char *)t - bh->b_data))
> return 0;
>
> return 1;
> }
>
> -static void ext4_dirent_csum_set(struct inode *inode,
> - struct ext4_dir_entry *dirent)
> +static void ext4_dirblock_csum_set(struct inode *inode,
> + struct buffer_head *bh)
> {
> struct ext4_dir_entry_tail *t;
>
> if (!ext4_has_metadata_csum(inode->i_sb))
> return;
>
> - t = get_dirent_tail(inode, dirent);
> + t = get_dirent_tail(inode, bh);
> if (!t) {
> warn_no_space_for_csum(inode);
> return;
> }
>
> - t->det_checksum = ext4_dirent_csum(inode, dirent,
> - (void *)t - (void *)dirent);
> + t->det_checksum = ext4_dirblock_csum(inode, bh->b_data,
> + (char *)t - bh->b_data);
> }
>
> -int ext4_handle_dirty_dirent_node(handle_t *handle,
> - struct inode *inode,
> - struct buffer_head *bh)
> +int ext4_handle_dirty_dirblock(handle_t *handle,
> + struct inode *inode,
> + struct buffer_head *bh)
> {
> - ext4_dirent_csum_set(inode, (struct ext4_dir_entry *)bh->b_data);
> + ext4_dirblock_csum_set(inode, bh);
> return ext4_handle_dirty_metadata(handle, inode, bh);
> }
>
> @@ -1530,8 +1529,7 @@ static struct buffer_head *__ext4_find_entry(struct inode *dir,
> if (!buffer_verified(bh) &&
> !is_dx_internal_node(dir, block,
> (struct ext4_dir_entry *)bh->b_data) &&
> - !ext4_dirent_csum_verify(dir,
> - (struct ext4_dir_entry *)bh->b_data)) {
> + !ext4_dirblock_csum_verify(dir, bh)) {
> EXT4_ERROR_INODE(dir, "checksumming directory "
> "block %lu", (unsigned long)block);
> brelse(bh);
> @@ -1894,7 +1892,7 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
> de = de2;
> }
> dx_insert_block(frame, hash2 + continued, newblock);
> - err = ext4_handle_dirty_dirent_node(handle, dir, bh2);
> + err = ext4_handle_dirty_dirblock(handle, dir, bh2);
> if (err)
> goto journal_error;
> err = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
> @@ -2022,7 +2020,7 @@ static int add_dirent_to_buf(handle_t *handle, struct ext4_filename *fname,
> inode_inc_iversion(dir);
> ext4_mark_inode_dirty(handle, dir);
> BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
> - err = ext4_handle_dirty_dirent_node(handle, dir, bh);
> + err = ext4_handle_dirty_dirblock(handle, dir, bh);
> if (err)
> ext4_std_error(dir->i_sb, err);
> return 0;
> @@ -2126,7 +2124,7 @@ static int make_indexed_dir(handle_t *handle, struct ext4_filename *fname,
> retval = ext4_handle_dirty_dx_node(handle, dir, frame->bh);
> if (retval)
> goto out_frames;
> - retval = ext4_handle_dirty_dirent_node(handle, dir, bh2);
> + retval = ext4_handle_dirty_dirblock(handle, dir, bh2);
> if (retval)
> goto out_frames;
>
> @@ -2512,7 +2510,7 @@ static int ext4_delete_entry(handle_t *handle,
> goto out;
>
> BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
> - err = ext4_handle_dirty_dirent_node(handle, dir, bh);
> + err = ext4_handle_dirty_dirblock(handle, dir, bh);
> if (unlikely(err))
> goto out;
>
> @@ -2744,7 +2742,7 @@ static int ext4_init_new_dir(handle_t *handle, struct inode *dir,
> }
>
> BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata");
> - err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
> + err = ext4_handle_dirty_dirblock(handle, inode, dir_block);
> if (err)
> goto out;
> set_buffer_verified(dir_block);
> @@ -3492,9 +3490,8 @@ static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent,
> ent->inode,
> ent->dir_bh);
> } else {
> - retval = ext4_handle_dirty_dirent_node(handle,
> - ent->inode,
> - ent->dir_bh);
> + retval = ext4_handle_dirty_dirblock(handle, ent->inode,
> + ent->dir_bh);
> }
> } else {
> retval = ext4_mark_inode_dirty(handle, ent->inode);
> @@ -3524,8 +3521,7 @@ static int ext4_setent(handle_t *handle, struct ext4_renament *ent,
> ext4_mark_inode_dirty(handle, ent->dir);
> BUFFER_TRACE(ent->bh, "call ext4_handle_dirty_metadata");
> if (!ent->inlined) {
> - retval = ext4_handle_dirty_dirent_node(handle,
> - ent->dir, ent->bh);
> + retval = ext4_handle_dirty_dirblock(handle, ent->dir, ent->bh);
> if (unlikely(retval)) {
> ext4_std_error(ent->dir->i_sb, retval);
> return retval;
> --
> 2.22.0
>
