1. The valid data will be within i_size.
2. All the trim operations will be done in a unit of block, even if
i_size is not aligned with BLKSIZE like the below.
index = F2FS_BYTES_TO_BLK(range.start);
pg_end = DIV_ROUND_UP(end_addr, F2FS_BLKSIZE); <= BLKSIZE aligned
Are you worried about the case that sudden power-off occurs while a
file is being truncated?
ex) 1GB file is being truncated to 4KB -> sudden power-off ->
i_size(4KB), i_blocks(maybe somewhere between 4KB and 1GB)
2020년 7월 10일 (금) 오후 12:02, Jaegeuk Kim <jaeg...@kernel.org>님이 작성:
>
> On 07/10, Daeho Jeong wrote:
> > From: Daeho Jeong <daehoje...@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 <daehoje...@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;
>
> Hmm, what if there are blocks beyond i_size? Do we need to check i_blocks for
> 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-de...@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
