This patch wouldn't merge due to a merge conflict here. Am I missing an earlier patch of yours before the series? I have these in for-next: d1ea8f36fa51 (HEAD -> for-next) cifs: force interface update before a fresh session setup 1e27cedcaf4e (origin/for-next) cifs: do not reset chan_max if multichannel is not supported at mount e257df806ae0 cifs: display the endpoint IP details in DebugData 9d95130c9f78 cifs: reconnect helper should set reconnect for the right channel 7ac6866076bd smb: client: fix use-after-free in smb2_query_info_compound() 0779365fc10d smb: client: remove extra @chan_count check in __cifs_put_smb_ses() 4cf6e1101a25 cifs: add xid to query server interface call 52768695d36a cifs: print server capabilities in DebugData --- fs/smb/client/connect.c +++ fs/smb/client/connect.c @@ -2037,7 +2041,9 @@ void __cifs_put_smb_ses(struct cifs_ses *ses) kref_put(&ses->chans[i].iface->refcount, release_iface); ses->chans[i].iface = NULL; } - cifs_put_tcp_session(ses->chans[i].server, 0); + + if (ses->chans[i].server) + cifs_put_tcp_session(ses->chans[i].server, 0); ses->chans[i].server = NULL; } } On Mon, Oct 30, 2023 at 6:00 AM <nspmangalore@xxxxxxxxx> wrote: > > From: Shyam Prasad N <sprasad@xxxxxxxxxxxxx> > > So far, SMB multichannel could only scale up, but not > scale down the number of channels. In this series of > patch, we now allow the client to deal with the case > of multichannel disabled on the server when the share > is mounted. With that change, we now need the ability > to scale down the channels. > > This change allows the client to deal with cases of > missing channels more gracefully. > > Signed-off-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx> > --- > fs/smb/client/cifs_debug.c | 5 +++++ > fs/smb/client/cifsglob.h | 1 + > fs/smb/client/cifsproto.h | 2 +- > fs/smb/client/connect.c | 10 ++++++++-- > fs/smb/client/sess.c | 25 +++++++++++++++++++++---- > fs/smb/client/smb2transport.c | 8 +++++++- > 6 files changed, 43 insertions(+), 8 deletions(-) > > diff --git a/fs/smb/client/cifs_debug.c b/fs/smb/client/cifs_debug.c > index a9dfecc397a8..9fca09539728 100644 > --- a/fs/smb/client/cifs_debug.c > +++ b/fs/smb/client/cifs_debug.c > @@ -136,6 +136,11 @@ cifs_dump_channel(struct seq_file *m, int i, struct cifs_chan *chan) > { > struct TCP_Server_Info *server = chan->server; > > + if (!server) { > + seq_printf(m, "\n\n\t\tChannel: %d DISABLED", i+1); > + return; > + } > + > seq_printf(m, "\n\n\t\tChannel: %d ConnectionId: 0x%llx" > "\n\t\tNumber of credits: %d,%d,%d Dialect 0x%x" > "\n\t\tTCP status: %d Instance: %d" > diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h > index 02082621d8e0..552ed441281a 100644 > --- a/fs/smb/client/cifsglob.h > +++ b/fs/smb/client/cifsglob.h > @@ -1050,6 +1050,7 @@ struct cifs_ses { > spinlock_t chan_lock; > /* ========= begin: protected by chan_lock ======== */ > #define CIFS_MAX_CHANNELS 16 > +#define CIFS_INVAL_CHAN_INDEX (-1) > #define CIFS_ALL_CHANNELS_SET(ses) \ > ((1UL << (ses)->chan_count) - 1) > #define CIFS_ALL_CHANS_GOOD(ses) \ > diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h > index 0c37eefa18a5..65c84b3d1a65 100644 > --- a/fs/smb/client/cifsproto.h > +++ b/fs/smb/client/cifsproto.h > @@ -616,7 +616,7 @@ bool is_server_using_iface(struct TCP_Server_Info *server, > bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface); > void cifs_ses_mark_for_reconnect(struct cifs_ses *ses); > > -unsigned int > +int > cifs_ses_get_chan_index(struct cifs_ses *ses, > struct TCP_Server_Info *server); > void > diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c > index 97c9a32cff36..8393977e21ee 100644 > --- a/fs/smb/client/connect.c > +++ b/fs/smb/client/connect.c > @@ -173,8 +173,12 @@ cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server, > list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) { > spin_lock(&ses->chan_lock); > for (i = 0; i < ses->chan_count; i++) { > + if (!ses->chans[i].server) > + continue; > + > spin_lock(&ses->chans[i].server->srv_lock); > - ses->chans[i].server->tcpStatus = CifsNeedReconnect; > + if (ses->chans[i].server->tcpStatus != CifsExiting) > + ses->chans[i].server->tcpStatus = CifsNeedReconnect; > spin_unlock(&ses->chans[i].server->srv_lock); > } > spin_unlock(&ses->chan_lock); > @@ -2033,7 +2037,9 @@ void __cifs_put_smb_ses(struct cifs_ses *ses) > kref_put(&ses->chans[i].iface->refcount, release_iface); > ses->chans[i].iface = NULL; > } > - cifs_put_tcp_session(ses->chans[i].server, 0); > + > + if (ses->chans[i].server) > + cifs_put_tcp_session(ses->chans[i].server, 0); > ses->chans[i].server = NULL; > } > } > diff --git a/fs/smb/client/sess.c b/fs/smb/client/sess.c > index c899b05c92f7..9d2228c2d7e5 100644 > --- a/fs/smb/client/sess.c > +++ b/fs/smb/client/sess.c > @@ -69,7 +69,7 @@ bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface) > > /* channel helper functions. assumed that chan_lock is held by caller. */ > > -unsigned int > +int > cifs_ses_get_chan_index(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > @@ -85,14 +85,16 @@ cifs_ses_get_chan_index(struct cifs_ses *ses, > cifs_dbg(VFS, "unable to get chan index for server: 0x%llx", > server->conn_id); > WARN_ON(1); > - return 0; > + return CIFS_INVAL_CHAN_INDEX; > } > > void > cifs_chan_set_in_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > - unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return; > > ses->chans[chan_index].in_reconnect = true; > } > @@ -102,6 +104,8 @@ cifs_chan_clear_in_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return; > > ses->chans[chan_index].in_reconnect = false; > } > @@ -111,6 +115,8 @@ cifs_chan_in_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return true; /* err on the safer side */ > > return CIFS_CHAN_IN_RECONNECT(ses, chan_index); > } > @@ -120,6 +126,8 @@ cifs_chan_set_need_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return; > > set_bit(chan_index, &ses->chans_need_reconnect); > cifs_dbg(FYI, "Set reconnect bitmask for chan %u; now 0x%lx\n", > @@ -131,6 +139,8 @@ cifs_chan_clear_need_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return; > > clear_bit(chan_index, &ses->chans_need_reconnect); > cifs_dbg(FYI, "Cleared reconnect bitmask for chan %u; now 0x%lx\n", > @@ -142,6 +152,8 @@ cifs_chan_needs_reconnect(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return true; /* err on the safer side */ > > return CIFS_CHAN_NEEDS_RECONNECT(ses, chan_index); > } > @@ -151,6 +163,8 @@ cifs_chan_is_iface_active(struct cifs_ses *ses, > struct TCP_Server_Info *server) > { > unsigned int chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return true; /* err on the safer side */ > > return ses->chans[chan_index].iface && > ses->chans[chan_index].iface->is_active; > @@ -269,7 +283,7 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server) > > spin_lock(&ses->chan_lock); > chan_index = cifs_ses_get_chan_index(ses, server); > - if (!chan_index) { > + if (chan_index == CIFS_INVAL_CHAN_INDEX) { > spin_unlock(&ses->chan_lock); > return 0; > } > @@ -319,6 +333,9 @@ cifs_chan_update_iface(struct cifs_ses *ses, struct TCP_Server_Info *server) > > spin_lock(&ses->chan_lock); > chan_index = cifs_ses_get_chan_index(ses, server); > + if (chan_index == CIFS_INVAL_CHAN_INDEX) > + return 0; > + > ses->chans[chan_index].iface = iface; > > /* No iface is found. if secondary chan, drop connection */ > diff --git a/fs/smb/client/smb2transport.c b/fs/smb/client/smb2transport.c > index 23c50ed7d4b5..84ea67301303 100644 > --- a/fs/smb/client/smb2transport.c > +++ b/fs/smb/client/smb2transport.c > @@ -413,7 +413,13 @@ generate_smb3signingkey(struct cifs_ses *ses, > ses->ses_status == SES_GOOD); > > chan_index = cifs_ses_get_chan_index(ses, server); > - /* TODO: introduce ref counting for channels when the can be freed */ > + if (chan_index == CIFS_INVAL_CHAN_INDEX) { > + spin_unlock(&ses->chan_lock); > + spin_unlock(&ses->ses_lock); > + > + return -EINVAL; > + } > + > spin_unlock(&ses->chan_lock); > spin_unlock(&ses->ses_lock); > > -- > 2.34.1 > -- Thanks, Steve