linux-kernel - Re: [PATCH v2] f2fs: change the way of handling range.len in F2FS_IOC_SEC_TRIM

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Date:   Tue, 14 Jul 2020 08:34:21 +0900
From:   Daeho Jeong <daeho43@...il.com>
To:     Jaegeuk Kim <jaegeuk@...nel.org>
Cc:     linux-kernel@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net, kernel-team@...roid.com,
        Daeho Jeong <daehojeong@...gle.com>
Subject: Re: [PATCH v2] f2fs: change the way of handling range.len in F2FS_IOC_SEC_TRIM_FILE

It's correct~ :)

2020년 7월 14일 (화) 오전 3:11, Jaegeuk Kim <jaegeuk@...nel.org>님이 작성:
>
> Hi Daeho,
>
> Please take a look at this.
>
> https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev&id=35245180459aebf6d70fde88a538f0400a794aa6
>
> Thanks,
>
> On 07/13, Daeho Jeong wrote:
> > From: Daeho Jeong <daehojeong@...gle.com>
> >
> > Changed the way of handling range.len of F2FS_IOC_SEC_TRIM_FILE.
> >  1. Added -1 value support for range.len to secure trim the whole blocks
> >     starting from range.start regardless of i_size.
> >  2. If the end of the range passes over the end of file, it means until
> >     the end of file (i_size).
> >  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@...gle.com>
> > ---
> > Changes in v2:
> >  - Changed -1 range.len option to mean the whole blocks starting from
> >    range.start regardless of i_size
> > ---
> >  fs/f2fs/file.c | 23 ++++++++++++-----------
> >  1 file changed, 12 insertions(+), 11 deletions(-)
> >
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index 368c80f8e2a1..2485841e3b2d 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -3792,7 +3792,7 @@ static int f2fs_sec_trim_file(struct file *filp, unsigned long arg)
> >       pgoff_t index, pg_end;
> >       block_t prev_block = 0, len = 0;
> >       loff_t end_addr;
> > -     bool to_end;
> > +     bool to_end = false;
> >       int ret = 0;
> >
> >       if (!(filp->f_mode & FMODE_WRITE))
> > @@ -3813,23 +3813,23 @@ 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;
> > +     if (inode->i_size - range.start > range.len) {
> > +             end_addr = range.start + range.len;
> > +     } else {
> > +             end_addr = range.len == (u64)-1 ?
> > +                     sbi->sb->s_maxbytes : inode->i_size;
> > +             to_end = true;
> >       }
> > -     end_addr = range.start + range.len;
> >
> > -     to_end = (end_addr == inode->i_size);
> >       if (!IS_ALIGNED(range.start, F2FS_BLKSIZE) ||
> >                       (!to_end && !IS_ALIGNED(end_addr, F2FS_BLKSIZE))) {
> >               ret = -EINVAL;
> > @@ -3846,7 +3846,8 @@ static int f2fs_sec_trim_file(struct file *filp, unsigned long arg)
> >       down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]);
> >       down_write(&F2FS_I(inode)->i_mmap_sem);
> >
> > -     ret = filemap_write_and_wait_range(mapping, range.start, end_addr - 1);
> > +     ret = filemap_write_and_wait_range(mapping, range.start,
> > +                     to_end ? LLONG_MAX : end_addr - 1);
> >       if (ret)
> >               goto out;
> >
> > --
> > 2.27.0.383.g050319c2ae-goog