Messages in this thread | | | Subject | Re: [f2fs-dev] [PATCH] f2fs: change the way of handling range.len in F2FS_IOC_SEC_TRIM_FILE | From | Chao Yu <> | Date | Fri, 10 Jul 2020 15:29:58 +0800 |
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On 2020/7/10 14:46, Jaegeuk Kim wrote: > On 07/10, Chao Yu wrote: >> On 2020/7/10 11:52, Jaegeuk Kim wrote: >>> On 07/10, Chao Yu wrote: >>>> On 2020/7/10 11:31, Jaegeuk Kim wrote: >>>>> On 07/10, Chao Yu wrote: >>>>>> On 2020/7/10 11:02, Jaegeuk Kim wrote: >>>>>>> On 07/10, Daeho Jeong wrote: >>>>>>>> From: Daeho Jeong <daehojeong@google.com> >>>>>>>> >>>>>>>> Changed the way of handling range.len of F2FS_IOC_SEC_TRIM_FILE. >>>>>>>> 1. Added -1 value support for range.len to signify the end of file. >>>>>>>> 2. If the end of the range passes over the end of file, it means until >>>>>>>> the end of file. >>>>>>>> 3. ignored the case of that range.len is zero to prevent the function >>>>>>>> from making end_addr zero and triggering different behaviour of >>>>>>>> the function. >>>>>>>> >>>>>>>> Signed-off-by: Daeho Jeong <daehojeong@google.com> >>>>>>>> --- >>>>>>>> fs/f2fs/file.c | 16 +++++++--------- >>>>>>>> 1 file changed, 7 insertions(+), 9 deletions(-) >>>>>>>> >>>>>>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c >>>>>>>> index 368c80f8e2a1..1c4601f99326 100644 >>>>>>>> --- a/fs/f2fs/file.c >>>>>>>> +++ b/fs/f2fs/file.c >>>>>>>> @@ -3813,21 +3813,19 @@ static int f2fs_sec_trim_file(struct file *filp, unsigned long arg) >>>>>>>> file_start_write(filp); >>>>>>>> inode_lock(inode); >>>>>>>> >>>>>>>> - if (f2fs_is_atomic_file(inode) || f2fs_compressed_file(inode)) { >>>>>>>> + if (f2fs_is_atomic_file(inode) || f2fs_compressed_file(inode) || >>>>>>>> + range.start >= inode->i_size) { >>>>>>>> ret = -EINVAL; >>>>>>>> goto err; >>>>>>>> } >>>>>>>> >>>>>>>> - if (range.start >= inode->i_size) { >>>>>>>> - ret = -EINVAL; >>>>>>>> + if (range.len == 0) >>>>>>>> goto err; >>>>>>>> - } >>>>>>>> >>>>>>>> - if (inode->i_size - range.start < range.len) { >>>>>>>> - ret = -E2BIG; >>>>>>>> - goto err; >>>>>>>> - } >>>>>>>> - end_addr = range.start + range.len; >>>>>>>> + if (range.len == (u64)-1 || inode->i_size - range.start < range.len) >>>>>>>> + end_addr = inode->i_size; >>>>>> >>>>>> We can remove 'range.len == (u64)-1' condition since later condition can cover >>>>>> this? >>>>>> >>>>>>> >>>>>>> Hmm, what if there are blocks beyond i_size? Do we need to check i_blocks for >>>>>> >>>>>> The blocks beyond i_size will never be written, there won't be any valid message >>>>>> there, so we don't need to worry about that. >>>>> >>>>> I don't think we have a way to guarantee the order of i_size and block >>>>> allocation in f2fs. See f2fs_write_begin and f2fs_write_end. >>>> >>>> However, write_begin & write_end are covered by inode_lock, it could not be >>>> racy with inode size check in f2fs_sec_trim_file() as it hold inode_lock as >>>> well? >>> >>> Like Daeho said, write_begin -> checkpoint -> power-cut can give bigger i_blocks >>> than i_size. >> >> The path won't, cp only persists reserved block in dnode rather than written >> data block in segment, because data will be copied to page cache after write_begin. > > Ah, you're talking about data validity, while I was doing block allocation in > this case. In either cases, I'd say secure_trim needs to trim whatever data > in valid block *address*.
Yeah, I agreed, sec_trim should trim all data no matter locating inside or beyond isize.
> >> >> I think truncation path could as Daeho said: >> >> 1. truncate -> i_size update however blocks wasn't truncated yet -> checkpoint -> recovery >> 2. truncate failed -> i_size update however partial blocks was truncated -> fsync >> >>> >>>> >>>>> >>>>>> >>>>>> Thanks, >>>>>> >>>>>>> ending criteria? >>>>>>> >>>>>>>> + else >>>>>>>> + end_addr = range.start + range.len; >>>>>>>> >>>>>>>> to_end = (end_addr == inode->i_size); >>>>>>>> if (!IS_ALIGNED(range.start, F2FS_BLKSIZE) || >>>>>>>> -- >>>>>>>> 2.27.0.383.g050319c2ae-goog >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> Linux-f2fs-devel mailing list >>>>>>>> Linux-f2fs-devel@lists.sourceforge.net >>>>>>>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel >>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> Linux-f2fs-devel mailing list >>>>>>> Linux-f2fs-devel@lists.sourceforge.net >>>>>>> https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel >>>>>>> . >>>>>>> >>>>> . >>>>> >>> . >>> > . >
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