Pavel and I had talked about adding tracing in smb2_compound_op for
enter/exit since it allows more granularity (and with dynamic tracing,
overhead is small). Thoughts?
On Mon, Mar 11, 2019 at 7:02 AM ronnie sahlberg
<ronniesahlberg@xxxxxxxxx> wrote:
>
> As a followup discussion.
>
> We do tracing in SMB2_open() but not in SMB2_open_init(). Perhaps we
> should change this to do the actual tracing in SMB2_open_init()
> instead and catch ALL places where we try to open a file.
> Though, we don't actually have the result of the operation in
> _open_init() which means we may need to reconsider how we trace these
> things.
>
> As we will likely switch more and more things to be compounds, maybe
> we should not have tracing in SMB2_open() and have it trace
> trace_smb3_open_err()
>
> Maybe we should trace "smb2_init : constructing compound"
> and have trace_smb3_compound_error()
>
>
> We restructure the tracing to be focused around compounds instead of
> individual PDUs.
> I.e. tracing in all the _init() functions, then tracing in
> compound_send_recv() for success/error.
>
> Tracing success/error on pdu/compound level instead of individual
> open/close/read/... operations.
> For individual non-compounded commands we can still treat these the
> same. They are just trivial compounds of one single SMB2 PDU.
>
>
> On Mon, Mar 11, 2019 at 4:01 PM Ronnie Sahlberg <lsahlber@xxxxxxxxxx> wrote:
> >
> > When we open the shared root handle also ask for FILE_ALL_INFORMATION since
> > we can do this at zero cost as part of a compound.
> > Cache this information as long as the lease is return and serve any
> > future requests from cache.
> >
> > This allows us to serve "stat /<mountpoint>" directly from cache and avoid
> > a network roundtrip. Since clients ofthen need to do this quite a lot
> > this improve performance slightly.
> >
> > As an example: xfstest generic/533 performs 43 stat operations on the root
> > of the share while it is run. Which are eliminated with this patch.
> >
> > Signed-off-by: Ronnie Sahlberg <lsahlber@xxxxxxxxxx>
> > ---
> > fs/cifs/cifsglob.h | 3 ++
> > fs/cifs/smb2inode.c | 15 ++++---
> > fs/cifs/smb2ops.c | 111 +++++++++++++++++++++++++++++++++++++++++++---------
> > fs/cifs/smb2pdu.c | 12 +++---
> > fs/cifs/smb2proto.h | 3 ++
> > 5 files changed, 116 insertions(+), 28 deletions(-)
> >
> > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> > index f293e052e351..b8360ca221eb 100644
> > --- a/fs/cifs/cifsglob.h
> > +++ b/fs/cifs/cifsglob.h
> > @@ -962,11 +962,14 @@ cap_unix(struct cifs_ses *ses)
> >
> > struct cached_fid {
> > bool is_valid:1; /* Do we have a useable root fid */
> > + bool file_all_info_is_valid:1;
> > +
> > struct kref refcount;
> > struct cifs_fid *fid;
> > struct mutex fid_mutex;
> > struct cifs_tcon *tcon;
> > struct work_struct lease_break;
> > + struct smb2_file_all_info file_all_info;
> > };
> >
> > /*
> > diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
> > index 01a76bccdb8d..b6e07e2eed10 100644
> > --- a/fs/cifs/smb2inode.c
> > +++ b/fs/cifs/smb2inode.c
> > @@ -309,12 +309,17 @@ smb2_query_path_info(const unsigned int xid, struct cifs_tcon *tcon,
> > rc = open_shroot(xid, tcon, &fid);
> > if (rc)
> > goto out;
> > - rc = SMB2_query_info(xid, tcon, fid.persistent_fid,
> > - fid.volatile_fid, smb2_data);
> > +
> > + if (tcon->crfid.file_all_info_is_valid) {
> > + move_smb2_info_to_cifs(data,
> > + &tcon->crfid.file_all_info);
> > + } else {
> > + rc = SMB2_query_info(xid, tcon, fid.persistent_fid,
> > + fid.volatile_fid, smb2_data);
> > + if (!rc)
> > + move_smb2_info_to_cifs(data, smb2_data);
> > + }
> > close_shroot(&tcon->crfid);
> > - if (rc)
> > - goto out;
> > - move_smb2_info_to_cifs(data, smb2_data);
> > goto out;
> > }
> >
> > diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
> > index 085e91436da7..0d8bf87592ff 100644
> > --- a/fs/cifs/smb2ops.c
> > +++ b/fs/cifs/smb2ops.c
> > @@ -619,6 +619,7 @@ smb2_close_cached_fid(struct kref *ref)
> > SMB2_close(0, cfid->tcon, cfid->fid->persistent_fid,
> > cfid->fid->volatile_fid);
> > cfid->is_valid = false;
> > + cfid->file_all_info_is_valid = false;
> > }
> > }
> >
> > @@ -643,9 +644,18 @@ smb2_cached_lease_break(struct work_struct *work)
> > */
> > int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid)
> > {
> > - struct cifs_open_parms oparams;
> > - int rc;
> > - __le16 srch_path = 0; /* Null - since an open of top of share */
> > + struct cifs_ses *ses = tcon->ses;
> > + struct TCP_Server_Info *server = ses->server;
> > + struct cifs_open_parms oparms;
> > + struct smb2_create_rsp *o_rsp = NULL;
> > + struct smb2_query_info_rsp *qi_rsp = NULL;
> > + int resp_buftype[2];
> > + struct smb_rqst rqst[2];
> > + struct kvec rsp_iov[2];
> > + struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
> > + struct kvec qi_iov[1];
> > + int rc, flags = 0;
> > + __le16 utf16_path = 0; /* Null - since an open of top of share */
> > u8 oplock = SMB2_OPLOCK_LEVEL_II;
> >
> > mutex_lock(&tcon->crfid.fid_mutex);
> > @@ -657,22 +667,87 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, struct cifs_fid *pfid)
> > return 0;
> > }
> >
> > - oparams.tcon = tcon;
> > - oparams.create_options = 0;
> > - oparams.desired_access = FILE_READ_ATTRIBUTES;
> > - oparams.disposition = FILE_OPEN;
> > - oparams.fid = pfid;
> > - oparams.reconnect = false;
> > -
> > - rc = SMB2_open(xid, &oparams, &srch_path, &oplock, NULL, NULL, NULL);
> > - if (rc == 0) {
> > - memcpy(tcon->crfid.fid, pfid, sizeof(struct cifs_fid));
> > - tcon->crfid.tcon = tcon;
> > - tcon->crfid.is_valid = true;
> > - kref_init(&tcon->crfid.refcount);
> > - kref_get(&tcon->crfid.refcount);
> > - }
> > + if (smb3_encryption_required(tcon))
> > + flags |= CIFS_TRANSFORM_REQ;
> > +
> > + memset(rqst, 0, sizeof(rqst));
> > + resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
> > + memset(rsp_iov, 0, sizeof(rsp_iov));
> > +
> > + /* Open */
> > + memset(&open_iov, 0, sizeof(open_iov));
> > + rqst[0].rq_iov = open_iov;
> > + rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;
> > +
> > + oparms.tcon = tcon;
> > + oparms.create_options = 0;
> > + oparms.desired_access = FILE_READ_ATTRIBUTES;
> > + oparms.disposition = FILE_OPEN;
> > + oparms.fid = pfid;
> > + oparms.reconnect = false;
> > +
> > + rc = SMB2_open_init(tcon, &rqst[0], &oplock, &oparms, &utf16_path);
> > + if (rc)
> > + goto oshr_exit;
> > + smb2_set_next_command(tcon, &rqst[0]);
> > +
> > + memset(&qi_iov, 0, sizeof(qi_iov));
> > + rqst[1].rq_iov = qi_iov;
> > + rqst[1].rq_nvec = 1;
> > +
> > + rc = SMB2_query_info_init(tcon, &rqst[1], COMPOUND_FID,
> > + COMPOUND_FID, FILE_ALL_INFORMATION,
> > + SMB2_O_INFO_FILE, 0,
> > + sizeof(struct smb2_file_all_info) +
> > + PATH_MAX * 2, 0, NULL);
> > + if (rc)
> > + goto oshr_exit;
> > +
> > + smb2_set_related(&rqst[1]);
> > +
> > + rc = compound_send_recv(xid, ses, flags, 2, rqst,
> > + resp_buftype, rsp_iov);
> > + if (rc)
> > + goto oshr_exit;
> > +
> > + o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
> > + oparms.fid->persistent_fid = o_rsp->PersistentFileId;
> > + oparms.fid->volatile_fid = o_rsp->VolatileFileId;
> > +#ifdef CONFIG_CIFS_DEBUG2
> > + oparms.fid->mid = le64_to_cpu(o_rsp->sync_hdr.MessageId);
> > +#endif /* CIFS_DEBUG2 */
> > +
> > + if (o_rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE)
> > + oplock = smb2_parse_lease_state(server, o_rsp,
> > + &oparms.fid->epoch,
> > + oparms.fid->lease_key);
> > + else
> > + goto oshr_exit;
> > +
> > +
> > + memcpy(tcon->crfid.fid, pfid, sizeof(struct cifs_fid));
> > + tcon->crfid.tcon = tcon;
> > + tcon->crfid.is_valid = true;
> > + kref_init(&tcon->crfid.refcount);
> > + kref_get(&tcon->crfid.refcount);
> > +
> > +
> > + qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
> > + rc = smb2_validate_and_copy_iov(
> > + le16_to_cpu(qi_rsp->OutputBufferOffset),
> > + le32_to_cpu(qi_rsp->OutputBufferLength),
> > + &rsp_iov[1], sizeof(struct smb2_file_all_info),
> > + (char *)&tcon->crfid.file_all_info);
> > + if (rc)
> > + goto oshr_exit;
> > + tcon->crfid.file_all_info_is_valid = 1;
> > +
> > + oshr_exit:
> > mutex_unlock(&tcon->crfid.fid_mutex);
> > + SMB2_open_free(&rqst[0]);
> > + SMB2_query_info_free(&rqst[1]);
> > + free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
> > + free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
> > return rc;
> > }
> >
> > diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
> > index 60fbe306f604..cfe9fe41ccf5 100644
> > --- a/fs/cifs/smb2pdu.c
> > +++ b/fs/cifs/smb2pdu.c
> > @@ -1797,9 +1797,10 @@ create_reconnect_durable_buf(struct cifs_fid *fid)
> > return buf;
> > }
> >
> > -static __u8
> > -parse_lease_state(struct TCP_Server_Info *server, struct smb2_create_rsp *rsp,
> > - unsigned int *epoch, char *lease_key)
> > +__u8
> > +smb2_parse_lease_state(struct TCP_Server_Info *server,
> > + struct smb2_create_rsp *rsp,
> > + unsigned int *epoch, char *lease_key)
> > {
> > char *data_offset;
> > struct create_context *cc;
> > @@ -2456,8 +2457,9 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
> > }
> >
> > if (rsp->OplockLevel == SMB2_OPLOCK_LEVEL_LEASE)
> > - *oplock = parse_lease_state(server, rsp, &oparms->fid->epoch,
> > - oparms->fid->lease_key);
> > + *oplock = smb2_parse_lease_state(server, rsp,
> > + &oparms->fid->epoch,
> > + oparms->fid->lease_key);
> > else
> > *oplock = rsp->OplockLevel;
> > creat_exit:
> > diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
> > index 87733b27a65f..72cc563c32fe 100644
> > --- a/fs/cifs/smb2proto.h
> > +++ b/fs/cifs/smb2proto.h
> > @@ -223,6 +223,9 @@ extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *);
> >
> > extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *,
> > enum securityEnum);
> > +extern __u8 smb2_parse_lease_state(struct TCP_Server_Info *server,
> > + struct smb2_create_rsp *rsp,
> > + unsigned int *epoch, char *lease_key);
> > extern int smb3_encryption_required(const struct cifs_tcon *tcon);
> > extern int smb2_validate_iov(unsigned int offset, unsigned int buffer_length,
> > struct kvec *iov, unsigned int min_buf_size);
> > --
> > 2.13.6
> >
--
Thanks,
Steve
