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Date: Tue, 31 Dec 2019 09:22:36 +0800
From: Chao Yu <yuchao0@...wei.com>
To: Jaegeuk Kim <jaegeuk@...nel.org>
CC: <linux-kernel@...r.kernel.org>,
<linux-f2fs-devel@...ts.sourceforge.net>
Subject: Re: [f2fs-dev] [PATCH 1/4] f2fs: convert inline_dir early before
starting rename
On 2019/12/31 8:06, Jaegeuk Kim wrote:
> On 12/28, Chao Yu wrote:
>> On 2019/12/19 4:09, Jaegeuk Kim wrote:
>>> If we hit an error during rename, we'll get two dentries in different
>>> directories.
>>>
>>> Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
>>> ---
>>> fs/f2fs/f2fs.h | 1 +
>>> fs/f2fs/inline.c | 30 ++++++++++++++++++++++++++++--
>>> fs/f2fs/namei.c | 36 +++++++++++++-----------------------
>>> 3 files changed, 42 insertions(+), 25 deletions(-)
>>>
>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>> index dbc20d33d0e1..8d64525743cb 100644
>>> --- a/fs/f2fs/f2fs.h
>>> +++ b/fs/f2fs/f2fs.h
>>> @@ -3490,6 +3490,7 @@ void f2fs_truncate_inline_inode(struct inode *inode,
>>> int f2fs_read_inline_data(struct inode *inode, struct page *page);
>>> int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page);
>>> int f2fs_convert_inline_inode(struct inode *inode);
>>> +int f2fs_convert_inline_dir(struct inode *dir);
>>> int f2fs_write_inline_data(struct inode *inode, struct page *page);
>>> bool f2fs_recover_inline_data(struct inode *inode, struct page *npage);
>>> struct f2fs_dir_entry *f2fs_find_in_inline_dir(struct inode *dir,
>>> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
>>> index 52f85ed07a15..f82c3d9cf333 100644
>>> --- a/fs/f2fs/inline.c
>>> +++ b/fs/f2fs/inline.c
>>> @@ -530,7 +530,7 @@ static int f2fs_move_rehashed_dirents(struct inode *dir, struct page *ipage,
>>> return err;
>>> }
>>>
>>> -static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
>>> +static int do_convert_inline_dir(struct inode *dir, struct page *ipage,
>>> void *inline_dentry)
>>> {
>>> if (!F2FS_I(dir)->i_dir_level)
>>> @@ -539,6 +539,32 @@ static int f2fs_convert_inline_dir(struct inode *dir, struct page *ipage,
>>> return f2fs_move_rehashed_dirents(dir, ipage, inline_dentry);
>>> }
>>>
>>> +int f2fs_convert_inline_dir(struct inode *dir)
>>> +{
>>> + struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
>>> + struct page *ipage;
>>> + void *inline_dentry = NULL;
>>> + int err;
>>> +
>>> + if (!f2fs_has_inline_dentry(dir))
>>> + return 0;
>>> +
>>> + f2fs_lock_op(sbi);
>>> +
>>> + ipage = f2fs_get_node_page(sbi, dir->i_ino);
>>> + if (IS_ERR(ipage))
>>> + return PTR_ERR(ipage);
>>> +
>>> + inline_dentry = inline_data_addr(dir, ipage);
>>> +
>>> + err = do_convert_inline_dir(dir, ipage, inline_dentry);
>>> + if (!err)
>>> + f2fs_put_page(ipage, 1);
>>> +
>>> + f2fs_unlock_op(sbi);
>>> + return err;
>>> +}
>>> +
>>> int f2fs_add_inline_entry(struct inode *dir, const struct qstr *new_name,
>>> const struct qstr *orig_name,
>>> struct inode *inode, nid_t ino, umode_t mode)
>>> @@ -562,7 +588,7 @@ int f2fs_add_inline_entry(struct inode *dir, const struct qstr *new_name,
>>>
>>> bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
>>> if (bit_pos >= d.max) {
>>> - err = f2fs_convert_inline_dir(dir, ipage, inline_dentry);
>>> + err = do_convert_inline_dir(dir, ipage, inline_dentry);
>>> if (err)
>>> return err;
>>> err = -EAGAIN;
>>> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
>>> index 5d9584281935..61615ab466c2 100644
>>> --- a/fs/f2fs/namei.c
>>> +++ b/fs/f2fs/namei.c
>>> @@ -855,7 +855,6 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>>> struct f2fs_dir_entry *old_dir_entry = NULL;
>>> struct f2fs_dir_entry *old_entry;
>>> struct f2fs_dir_entry *new_entry;
>>> - bool is_old_inline = f2fs_has_inline_dentry(old_dir);
>>> int err;
>>>
>>> if (unlikely(f2fs_cp_error(sbi)))
>>> @@ -868,6 +867,19 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>>> F2FS_I(old_dentry->d_inode)->i_projid)))
>>> return -EXDEV;
>>>
>>> + /*
>>> + * old entry and new entry can locate in the same inline
>>> + * dentry in inode, when attaching new entry in inline dentry,
>>> + * it could force inline dentry conversion, after that,
>>> + * old_entry and old_page will point to wrong address, in
>>> + * order to avoid this, let's do the check and update here.
>>> + */
>>
>> The comment is out-of-update here...
>>
>> If there is enough room for the new dentry in old directory's inline space,
>> how about just keeping inline dir state for old directory?
>
> It'd work, but how can we deal with race conditions?
In rename() syscall, both src/dst's parent inode lock should has been hold to
prevent race condition.
Thanks,
>
>>
>>
>> ---
>> fs/f2fs/dir.c | 14 ++++++++++++++
>> fs/f2fs/f2fs.h | 4 +++-
>> fs/f2fs/inline.c | 22 +++++++++++++++++-----
>> fs/f2fs/namei.c | 2 +-
>> 4 files changed, 35 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
>> index c967cacf979e..b56f6060c1a6 100644
>> --- a/fs/f2fs/dir.c
>> +++ b/fs/f2fs/dir.c
>> @@ -578,6 +578,20 @@ int f2fs_room_for_filename(const void *bitmap, int slots, int max_slots)
>> goto next;
>> }
>>
>> +bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
>> + struct fscrypt_name *fname)
>> +{
>> + struct f2fs_dentry_ptr d;
>> + unsigned int bit_pos;
>> + int slots = GET_DENTRY_SLOTS(fname_len(fname));
>> +
>> + make_dentry_ptr_inline(dir, &d, inline_data_addr(dir, ipage));
>> +
>> + bit_pos = f2fs_room_for_filename(d.bitmap, slots, d.max);
>> +
>> + return bit_pos < d.max;
>> +}
>> +
>> void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
>> const struct qstr *name, f2fs_hash_t name_hash,
>> unsigned int bit_pos)
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 5d55cef66410..ce4ce33a40ce 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -3120,6 +3120,8 @@ ino_t f2fs_inode_by_name(struct inode *dir, const struct qstr *qstr,
>> struct page **page);
>> void f2fs_set_link(struct inode *dir, struct f2fs_dir_entry *de,
>> struct page *page, struct inode *inode);
>> +bool f2fs_has_enough_room(struct inode *dir, struct page *ipage,
>> + struct fscrypt_name *fname);
>> void f2fs_update_dentry(nid_t ino, umode_t mode, struct f2fs_dentry_ptr *d,
>> const struct qstr *name, f2fs_hash_t name_hash,
>> unsigned int bit_pos);
>> @@ -3662,7 +3664,7 @@ void f2fs_truncate_inline_inode(struct inode *inode,
>> int f2fs_read_inline_data(struct inode *inode, struct page *page);
>> int f2fs_convert_inline_page(struct dnode_of_data *dn, struct page *page);
>> int f2fs_convert_inline_inode(struct inode *inode);
>> -int f2fs_convert_inline_dir(struct inode *dir);
>> +int f2fs_try_convert_inline_dir(struct inode *dir, struct dentry *dentry);
>> int f2fs_write_inline_data(struct inode *inode, struct page *page);
>> bool f2fs_recover_inline_data(struct inode *inode, struct page *npage);
>> struct f2fs_dir_entry *f2fs_find_in_inline_dir(struct inode *dir,
>> diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
>> index f82c3d9cf333..4167e5408151 100644
>> --- a/fs/f2fs/inline.c
>> +++ b/fs/f2fs/inline.c
>> @@ -539,28 +539,40 @@ static int do_convert_inline_dir(struct inode *dir, struct page *ipage,
>> return f2fs_move_rehashed_dirents(dir, ipage, inline_dentry);
>> }
>>
>> -int f2fs_convert_inline_dir(struct inode *dir)
>> +int f2fs_try_convert_inline_dir(struct inode *dir, struct dentry *dentry)
>> {
>> struct f2fs_sb_info *sbi = F2FS_I_SB(dir);
>> struct page *ipage;
>> + struct fscrypt_name fname;
>> void *inline_dentry = NULL;
>> - int err;
>> + int err = 0;
>>
>> if (!f2fs_has_inline_dentry(dir))
>> return 0;
>>
>> f2fs_lock_op(sbi);
>>
>> + err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &fname);
>> + if (err)
>> + goto out;
>> +
>> ipage = f2fs_get_node_page(sbi, dir->i_ino);
>> - if (IS_ERR(ipage))
>> - return PTR_ERR(ipage);
>> + if (IS_ERR(ipage)) {
>> + err = PTR_ERR(ipage);
>> + goto out;
>> + }
>> +
>> + if (f2fs_has_enough_room(dir, ipage, &fname)) {
>> + f2fs_put_page(ipage, 1);
>> + goto out;
>> + }
>>
>> inline_dentry = inline_data_addr(dir, ipage);
>>
>> err = do_convert_inline_dir(dir, ipage, inline_dentry);
>> if (!err)
>> f2fs_put_page(ipage, 1);
>> -
>> +out:
>> f2fs_unlock_op(sbi);
>> return err;
>> }
>> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
>> index 1daa54c8d8d8..856f0f984549 100644
>> --- a/fs/f2fs/namei.c
>> +++ b/fs/f2fs/namei.c
>> @@ -927,7 +927,7 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>> * order to avoid this, let's do the check and update here.
>> */
>> if (old_dir == new_dir && !new_inode) {
>> - err = f2fs_convert_inline_dir(old_dir);
>> + err = f2fs_try_convert_inline_dir(old_dir, new_dentry);
>> if (err)
>> return err;
>> }
>> --
>> 2.18.0.rc1
>>
>> Thanks,
>>
>>> + if (old_dir == new_dir && !new_inode) {
>>> + err = f2fs_convert_inline_dir(old_dir);
>>> + if (err)
>>> + return err;
>>> + }
>>> +
>>> if (flags & RENAME_WHITEOUT) {
>>> err = f2fs_create_whiteout(old_dir, &whiteout);
>>> if (err)
>>> @@ -954,28 +966,6 @@ static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry,
>>>
>>> if (old_dir_entry)
>>> f2fs_i_links_write(new_dir, true);
>>> -
>>> - /*
>>> - * old entry and new entry can locate in the same inline
>>> - * dentry in inode, when attaching new entry in inline dentry,
>>> - * it could force inline dentry conversion, after that,
>>> - * old_entry and old_page will point to wrong address, in
>>> - * order to avoid this, let's do the check and update here.
>>> - */
>>> - if (is_old_inline && !f2fs_has_inline_dentry(old_dir)) {
>>> - f2fs_put_page(old_page, 0);
>>> - old_page = NULL;
>>> -
>>> - old_entry = f2fs_find_entry(old_dir,
>>> - &old_dentry->d_name, &old_page);
>>> - if (!old_entry) {
>>> - err = -ENOENT;
>>> - if (IS_ERR(old_page))
>>> - err = PTR_ERR(old_page);
>>> - f2fs_unlock_op(sbi);
>>> - goto out_dir;
>>> - }
>>> - }
>>> }
>>>
>>> down_write(&F2FS_I(old_inode)->i_sem);
>>>
> .
>
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