________________________________________
From: Miao Xie [miaoxie@xxxxxxxxxx]
Sent: Friday, June 30, 2017 16:48
To: Wang Shilong; linux-ext4@xxxxxxxxxxxxxxx
Cc: tytso@xxxxxxx; Li Xi; yi.zhang@xxxxxxxxxx; adilger@xxxxxxxxx; Wang Shilong; Shuichi Ihara
Subject: Re: [PATCH 1/2] ext4, project: expand inode extra size if possible
on 2017/6/30 at 11:51, Wang Shilong wrote:
> when upgrading from old format, try to set project id
> to old file first time, it will return EOVERFLOW, but if
> that file is dirtied(touch etc), changing project id will
> be allowed, this might be confusing for users, we could
> try to expand @i_extra_iszie here too.
>
> Reported-by: zhangyi(F) <yi.zhang@xxxxxxxxxx>
> Signed-off-by: Wang Shilong <wshilong@xxxxxxx>
> ---
> fs/ext4/ext4.h | 3 +++
> fs/ext4/inode.c | 7 +++----
> fs/ext4/ioctl.c | 17 +++++++++++++++--
> 3 files changed, 21 insertions(+), 6 deletions(-)
>
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 3219154..640f006 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -2453,6 +2453,9 @@ int ext4_walk_page_buffers(handle_t *handle,
> int *partial,
> int (*fn)(handle_t *handle,
> struct buffer_head *bh));
> +int ext4_expand_extra_isize(struct inode *inode,
> + unsigned int new_extra_isize,
> + struct ext4_iloc iloc, handle_t *handle);
> int do_journal_get_write_access(handle_t *handle,
> struct buffer_head *bh);
> #define FALL_BACK_TO_NONDELALLOC 1
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 5cf82d0..d53fae6 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -5632,10 +5632,9 @@ ext4_reserve_inode_write(handle_t *handle, struct inode *inode,
> * Expand an inode by new_extra_isize bytes.
> * Returns 0 on success or negative error number on failure.
> */
> -static int ext4_expand_extra_isize(struct inode *inode,
> - unsigned int new_extra_isize,
> - struct ext4_iloc iloc,
> - handle_t *handle)
> +int ext4_expand_extra_isize(struct inode *inode,
> + unsigned int new_extra_isize,
> + struct ext4_iloc iloc, handle_t *handle)
> {
> struct ext4_inode *raw_inode;
> struct ext4_xattr_ibody_header *header;
> diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
> index 0c21e22..819f59d 100644
> --- a/fs/ext4/ioctl.c
> +++ b/fs/ext4/ioctl.c
> @@ -319,6 +319,7 @@ static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
> struct ext4_iloc iloc;
> struct ext4_inode *raw_inode;
> struct dquot *transfer_to[MAXQUOTAS] = { };
> + bool need_expand = false;
>
> if (!ext4_has_feature_project(sb)) {
> if (projid != EXT4_DEF_PROJID)
> @@ -350,7 +351,10 @@ static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
> goto out_unlock;
>
> raw_inode = ext4_raw_inode(&iloc);
> - if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) {
> + if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid) &&
> + !ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND)) {
> + need_expand = true;
> + } else if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) {
> err = -EOVERFLOW;
> brelse(iloc.bh);
> goto out_unlock;
> @@ -361,12 +365,21 @@ static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
>
> handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
> EXT4_QUOTA_INIT_BLOCKS(sb) +
> - EXT4_QUOTA_DEL_BLOCKS(sb) + 3);
> + EXT4_QUOTA_DEL_BLOCKS(sb) + 3 +
> + need_expand ? EXT4_DATA_TRANS_BLOCKS(sb) : 0);
> if (IS_ERR(handle)) {
> err = PTR_ERR(handle);
> goto out_unlock;
> }
>
> + if (need_expand) {
> + err = ext4_expand_extra_isize(inode,
> + EXT4_SB(sb)->s_want_extra_isize,
> + iloc, handle);
> + if (err)
> + goto out_stop;
> + }
> +
ext4_expand_extra_isize should be invoked after ext4_reserve_inode_write.
--->Yup, indeed.
And I think it is better to restructure ext4_expand_extra_isize by moving NO_EXPAND check,
nojournal check and journal credits extend into it, and then we just if i_projid is in
the inode or not, if not, invoke ext4_expand_extra_isize. (don't forget to do cleanup for
ext4_mark_inode_dirty), And then we can remove many check in the above code.
--->thanks for good suggestions, will fix it.
Thanks
Miao
> err = ext4_reserve_inode_write(handle, inode, &iloc);
> if (err)
> goto out_stop;
>
