From c481e9feee78c6ce1ba0a1c8c892049f6514f6cf Mon Sep 17 00:00:00 2001 From: Steve French Date: Mon, 14 Oct 2013 01:21:53 -0500 Subject: [PATCH] Query network adapter info at mount time for debugging When CONFIG_CIFS_STATS2 enabled query adapter info for debugging It is easy now in SMB3 to query the information about the server's network interfaces (and at least Windows 8 and above do this, if not other clients) there are some useful pieces of information you can get including: - all of the network interfaces that the server advertises (not just the one you are mounting over), and with SMB3 supporting multichannel this helps with more than just failover (also aggregating multiple sockets under one mount) - whether the adapter supports RSS (useful to know if you want to estimate whether setting up two or more socket connections to the same address is going to be faster due to RSS offload in the adapter) - whether the server supports RDMA - whether the server has IPv6 interfaces (if you connected over IPv4 but prefer IPv6 e.g.) - what the link speed is (you might want to reconnect over a higher speed interface if available) (Of course we could also rerequest this on every mount cheaplly to the same server, as Windows apparently does, so we can update the adapter info on new mounts, and also on every reconnect if the network interface drops temporarily - so we don't have to rely on info from the first mount to this server) It is trivial to request this information - and certainly will be useful when we get to the point of doing multichannel (and eventually RDMA), but some of this (linkspeed etc.) info may help for debugging in the meantime. Enable this request when CONFIG_CIFS_STATS2 is on (only for smb3 mounts since it is an SMB3 or later ioctl). Signed-off-by: Steve French --- fs/cifs/smb2ops.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 25759c89619a..c571be8cb76e 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -209,6 +209,32 @@ smb2_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info) return rsize; } +#ifdef CONFIG_CIFS_STATS2 +static int +SMB3_request_interfaces(const unsigned int xid, struct cifs_tcon *tcon) +{ + int rc; + unsigned int ret_data_len = 0; + struct network_interface_info_ioctl_rsp *out_buf; + + rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID, + FSCTL_QUERY_NETWORK_INTERFACE_INFO, true /* is_fsctl */, + NULL /* no data input */, 0 /* no data input */, + (char **)&out_buf, &ret_data_len); + + if ((rc == 0) && (ret_data_len > 0)) { + /* Dump info on first interface */ + cifs_dbg(FYI, "Adapter Capability 0x%x\t", + le32_to_cpu(out_buf->Capability)); + cifs_dbg(FYI, "Link Speed %lld\n", + le64_to_cpu(out_buf->LinkSpeed)); + } else + cifs_dbg(VFS, "error %d on ioctl to get interface list\n", rc); + + return rc; +} +#endif /* STATS2 */ + static void smb3_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon) { @@ -229,6 +255,10 @@ smb3_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon) if (rc) return; +#ifdef CONFIG_CIFS_STATS2 + SMB3_request_interfaces(xid, tcon); +#endif /* STATS2 */ + SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid, FS_ATTRIBUTE_INFORMATION); SMB2_QFS_attr(xid, tcon, fid.persistent_fid, fid.volatile_fid, -- 2.20.1