[PATCH 1/5] smb3: Move the flush out of smb2_copychunk_range() into its callers

[Steve French]

had some typos in the version I sent (forgot to remove a few lines and
missed an le64 conversion) - will resend updated version

On Mon, Aug 29, 2022 at 11:56 AM Steve French <smfrench at gmail.com> wrote:

> e.g. something like the following
>
>
> On Mon, Aug 29, 2022 at 12:06 AM Steve French <smfrench at gmail.com> wrote:
> >
> > Shouldn't this be using filemap_write_and_wait_range() not
> > filemap_write_and_wait as we see in similar code in ext4 (and
> > shouldn't it check rc in some of these cases)?   For example for the
> > copychunk_range example shouldn't the patch be modified similar to the
> > following:
> >
> > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> > index e9fb338b8e7e..51963e83daf7 100644
> > --- a/fs/cifs/cifsfs.c
> > +++ b/fs/cifs/cifsfs.c
> > @@ -1219,8 +1219,6 @@ ssize_t cifs_file_copychunk_range(unsigned int xid,
> >
> >         cifs_dbg(FYI, "copychunk range\n");
> >
> > -       filemap_write_and_wait(src_inode->i_mapping);
> > -
> >         if (!src_file->private_data || !dst_file->private_data) {
> >                 rc = -EBADF;
> >                 cifs_dbg(VFS, "missing cifsFileInfo on copy range src
> file\n");
> > @@ -1250,6 +1248,12 @@ ssize_t cifs_file_copychunk_range(unsigned int
> xid,
> >         lock_two_nondirectories(target_inode, src_inode);
> >
> >         cifs_dbg(FYI, "about to flush pages\n");
> > +
> > +       rc = filemap_write_and_wait_range(src_inode->i_mapping, off,
> > +                                         off + len - 1);
> > +        if (rc)
> > +               goto out;
> > +
> >         /* should we flush first and last page first */
> >         truncate_inode_pages(&target_inode->i_data, 0);
> >
> > On Tue, Aug 23, 2022 at 8:09 AM David Howells via samba-technical
> > <samba-technical at lists.samba.org> wrote:
> > >
> > > Move the flush out of smb2_copychunk_range() into its callers.  This
> will
> > > allow the pagecache to be invalidated between the flush and the
> operation
> > > in smb3_collapse_range() and smb3_insert_range().
> > >
> > > Signed-off-by: David Howells <dhowells at redhat.com>
> > > cc: Steve French <stfrench at microsoft.com>
> > > cc: Ronnie Sahlberg <lsahlber at redhat.com>
> > > ---
> > >
> > >  fs/cifs/cifsfs.c  |    2 ++
> > >  fs/cifs/smb2ops.c |   20 ++++++++------------
> > >  2 files changed, 10 insertions(+), 12 deletions(-)
> > >
> > > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> > > index f54d8bf2732a..e9fb338b8e7e 100644
> > > --- a/fs/cifs/cifsfs.c
> > > +++ b/fs/cifs/cifsfs.c
> > > @@ -1219,6 +1219,8 @@ ssize_t cifs_file_copychunk_range(unsigned int
> xid,
> > >
> > >         cifs_dbg(FYI, "copychunk range\n");
> > >
> > > +       filemap_write_and_wait(src_inode->i_mapping);
> > > +
> > >         if (!src_file->private_data || !dst_file->private_data) {
> > >                 rc = -EBADF;
> > >                 cifs_dbg(VFS, "missing cifsFileInfo on copy range src
> file\n");
> > > diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> > > index 96f3b0573606..7e3de6a0e1dc 100644
> > > --- a/fs/cifs/smb2ops.c
> > > +++ b/fs/cifs/smb2ops.c
> > > @@ -1600,17 +1600,8 @@ smb2_copychunk_range(const unsigned int xid,
> > >         int chunks_copied = 0;
> > >         bool chunk_sizes_updated = false;
> > >         ssize_t bytes_written, total_bytes_written = 0;
> > > -       struct inode *inode;
> > >
> > >         pcchunk = kmalloc(sizeof(struct copychunk_ioctl), GFP_KERNEL);
> > > -
> > > -       /*
> > > -        * We need to flush all unwritten data before we can send the
> > > -        * copychunk ioctl to the server.
> > > -        */
> > > -       inode = d_inode(trgtfile->dentry);
> > > -       filemap_write_and_wait(inode->i_mapping);
> > > -
> > >         if (pcchunk == NULL)
> > >                 return -ENOMEM;
> > >
> > > @@ -3689,6 +3680,8 @@ static long smb3_collapse_range(struct file
> *file, struct cifs_tcon *tcon,
> > >                 goto out;
> > >         }
> > >
> > > +       filemap_write_and_wait(inode->i_mapping);
> > > +
> > >         rc = smb2_copychunk_range(xid, cfile, cfile, off + len,
> > >                                   i_size_read(inode) - off - len, off);
> > >         if (rc < 0)
> > > @@ -3716,18 +3709,21 @@ static long smb3_insert_range(struct file
> *file, struct cifs_tcon *tcon,
> > >         int rc;
> > >         unsigned int xid;
> > >         struct cifsFileInfo *cfile = file->private_data;
> > > +       struct inode *inode = file_inode(file);
> > >         __le64 eof;
> > >         __u64  count;
> > >
> > >         xid = get_xid();
> > >
> > > -       if (off >= i_size_read(file->f_inode)) {
> > > +       if (off >= i_size_read(inode)) {
> > >                 rc = -EINVAL;
> > >                 goto out;
> > >         }
> > >
> > > -       count = i_size_read(file->f_inode) - off;
> > > -       eof = cpu_to_le64(i_size_read(file->f_inode) + len);
> > > +       count = i_size_read(inode) - off;
> > > +       eof = cpu_to_le64(i_size_read(inode) + len);
> > > +
> > > +       filemap_write_and_wait(inode->i_mapping);
> > >
> > >         rc = SMB2_set_eof(xid, tcon, cfile->fid.persistent_fid,
> > >                           cfile->fid.volatile_fid, cfile->pid, &eof);
> > >
> > >
> > >
> >
> >
> > --
> > Thanks,
> >
> > Steve
>
>
>
> --
> Thanks,
>
> Steve
>


-- 
Thanks,

Steve