Re: [PATCH AUTOSEL 4.20 65/77] CIFS: Do not assume one credit for async responses

[Sasha Levin]

On Fri, Feb 15, 2019 at 08:10:47PM +0000, Pavel Shilovskiy wrote:
> ÑÑ, 14 ÑÐÐÑ. 2019 Ð. Ð 18:40, Sasha Levin <sashal@xxxxxxxxxx>:
> > From: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
> >
> > [ Upstream commit 0fd1d37b0501efc6e295f56ab55cdaff784aa50c ]
> >
> > If we don't receive a response we can't assume that the server
> > granted one credit. Assume zero credits in such cases.
> >
> > Signed-off-by: Pavel Shilovsky <pshilov@xxxxxxxxxxxxx>
> > Reviewed-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> > Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
> > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> > ---
> >  fs/cifs/smb2pdu.c | 15 +++++++++++----
> >  1 file changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> > index d1ae7cdb236d..3c44c51310c4 100644
> > --- a/fs/cifs/smb2pdu.c
> > +++ b/fs/cifs/smb2pdu.c
> > @@ -2834,9 +2834,10 @@ smb2_echo_callback(struct mid_q_entry *mid)
> >  {
> >         struct TCP_Server_Info *server = mid->callback_data;
> >         struct smb2_echo_rsp *rsp = (struct smb2_echo_rsp *)mid->resp_buf;
> > -       unsigned int credits_received = 1;
> > +       unsigned int credits_received = 0;
> >
> > -       if (mid->mid_state == MID_RESPONSE_RECEIVED)
> > +       if (mid->mid_state == MID_RESPONSE_RECEIVED
> > +           || mid->mid_state == MID_RESPONSE_MALFORMED)
> >                 credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
> >
> >         DeleteMidQEntry(mid);
> > @@ -3093,7 +3094,7 @@ smb2_readv_callback(struct mid_q_entry *mid)
> >         struct TCP_Server_Info *server = tcon->ses->server;
> >         struct smb2_sync_hdr *shdr =
> >                                 (struct smb2_sync_hdr *)rdata->iov[0].iov_base;
> > -       unsigned int credits_received = 1;
> > +       unsigned int credits_received = 0;
> >         struct smb_rqst rqst = { .rq_iov = rdata->iov,
> >                                  .rq_nvec = 2,
> >                                  .rq_pages = rdata->pages,
> > @@ -3132,6 +3133,9 @@ smb2_readv_callback(struct mid_q_entry *mid)
> >                 task_io_account_read(rdata->got_bytes);
> >                 cifs_stats_bytes_read(tcon, rdata->got_bytes);
> >                 break;
> > +       case MID_RESPONSE_MALFORMED:
> > +               credits_received = le16_to_cpu(shdr->CreditRequest);
> > +               /* fall through */
> >         default:
> >                 if (rdata->result != -ENODATA)
> >                         rdata->result = -EIO;
> > @@ -3325,7 +3329,7 @@ smb2_writev_callback(struct mid_q_entry *mid)
> >         struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
> >         unsigned int written;
> >         struct smb2_write_rsp *rsp = (struct smb2_write_rsp *)mid->resp_buf;
> > -       unsigned int credits_received = 1;
> > +       unsigned int credits_received = 0;
> >
> >         switch (mid->mid_state) {
> >         case MID_RESPONSE_RECEIVED:
> > @@ -3353,6 +3357,9 @@ smb2_writev_callback(struct mid_q_entry *mid)
> >         case MID_RETRY_NEEDED:
> >                 wdata->result = -EAGAIN;
> >                 break;
> > +       case MID_RESPONSE_MALFORMED:
> > +               credits_received = le16_to_cpu(rsp->sync_hdr.CreditRequest);
> > +               /* fall through */
> >         default:
> >                 wdata->result = -EIO;
> >                 break;
> > --
> > 2.19.1
>
> Can you also apply the following patch to 4.20.y and 4.19.y, please?
>
> https://patchwork.ozlabs.org/patch/1030180/

I'll queue it up for the next cycle as it has dependencies on stable@
commits that didn't make it in yet and I don't want to mess up with
Greg's flow. Thanks you!

--
Thanks,
Sasha