To help debug credit starvation problems where we timeout
waiting for server to grant the client credits.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

When the server required encryption (but we didn't connect to it with the
"seal" mount option) we weren't displaying in /proc/fs/cifs/DebugData that
the tcon for that share was encrypted. Similarly we were not displaying
that signing was required when ses->sign was enabled (we only
checked ses->server->sign).  This makes it easier to debug when in
fact the connection is signed (or sealed), whether for performance
or security questions.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

A negative timeout is the same as the current behaviour, i.e. no timeout.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Reserve the last MAX_COMPOUND credits for any request asking for >1 credit.
This is to prevent future compound requests from becoming starved while waiting
for potentially many requests is there is a large number of concurrent
singe-credit requests.

However, we need to protect from servers that are very slow to hand out
new credits on new sessions so we only do this IFF there are 2*MAX_COMPOUND
(arbitrary) credits already in flight.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Change wait_for_free_credits() to allow waiting for >=1 credits instead of just
a single credit.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

and compute timeout and optyp from it.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Formatting of Kconfig files doesn't look so pretty, so just
take damp cloth and clean it up.
Signed-off-by: NEnrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: NSteve French <stfrench@microsoft.com>

We can end up building up credits too slowly to do large operations
(reads and writes for example) that require many credits. By
comparison most other SMB3 clients request many more (sometimes
thousands) of credits on all operations.  Increase
the number of credits we request on typical (non-large e.g
read/write) operations to 10 from 2 so we can build a pool of credits
faster.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

We don't want to break SMB sessions if we receive signals when
sending packets through the network. Fix it by masking off signals
inside __smb_send_rqst() to avoid partial packet sends due to
interrupts.

Return -EINTR if a signal is pending and only a part of the packet
was sent. Return a success status code if the whole packet was sent
regardless of signal being pending or not. This keeps a mid entry
for the request in the pending queue and allows the demultiplex
thread to handle a response from the server properly.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

When we attempt to send a packet while the demultiplex thread
is in the middle of cifs_reconnect() we may end up returning
-ENOTSOCK to upper layers. The intent here is to retry the request
once the TCP connection is up, so change it to return -EAGAIN
instead. The latter error code is retryable and the upper layers
will retry the request if needed.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Do not allow commands other than SMB2_NEGOTIATE to be sent over
recently established TCP connections. Return -EAGAIN to let upper
layers handle it properly.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

When we have a READ lease for a file and have just issued a write
operation to the server we need to purge the cache and set oplock/lease
level to NONE to avoid reading stale data. Currently we do that
only if a write operation succedeed thus not covering cases when
a request was sent to the server but a negative error code was
returned later for some other reasons (e.g. -EIOCBQUEUED or -EINTR).
Fix this by turning off caching regardless of the error code being
returned.

The patches fixes generic tests 075 and 112 from the xfs-tests.

Cc: <stable@vger.kernel.org>
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

For kerberos mounts, the cruid is helpful to display in
/proc/mounts in order to tell which uid's krb5 cache we
got the ticket for and to tell in the multiuser krb5 case
which local users (uids) we have Kerberos authentic sessions
for.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

When compiling with -Wformat, clang emits the following warnings:

fs/cifs/smb1ops.c:312:20: warning: format specifies type 'unsigned
short' but the argument has type 'unsigned int' [-Wformat]
                         tgt_total_cnt, total_in_tgt);
                                        ^~~~~~~~~~~~

fs/cifs/cifs_dfs_ref.c:289:4: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
                 ref->flags, ref->server_type);
                 ^~~~~~~~~~

fs/cifs/cifs_dfs_ref.c:289:16: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
                 ref->flags, ref->server_type);
                             ^~~~~~~~~~~~~~~~

fs/cifs/cifs_dfs_ref.c:291:4: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
                 ref->ref_flag, ref->path_consumed);
                 ^~~~~~~~~~~~~

fs/cifs/cifs_dfs_ref.c:291:19: warning: format specifies type 'short'
but the argument has type 'int' [-Wformat]
                 ref->ref_flag, ref->path_consumed);
                                ^~~~~~~~~~~~~~~~~~
The types of these arguments are unconditionally defined, so this patch
updates the format character to the correct ones for ints and unsigned
ints.

Link: https://github.com/ClangBuiltLinux/linux/issues/378Signed-off-by: NLouis Taylor <louis@kragniz.eu>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>

Adds dynamic trace points for the query_info_enter
and query_info_done (no error) case.  We only had one
existing trace point related to this which was on query_info
errors.  Note that these two new tracepoints are for the
non-compounded query_info paths.

Sample output (from: trace-cmd record -e smb3_query_info*)

          ls-24140 [001] .... 27811.866068: smb3_query_info_enter: xid=7 sid=0xd2d00587 tid=0xb5441939 fid=0xcf082bac class=18 type=0x1
          ls-24140 [001] .... 27811.867656: smb3_query_info_done: xid=7 sid=0xd2d00587 tid=0xb5441939 fid=0xcf082bac class=18 type=0x1
  getcifsacl-24149 [005] .... 27854.759873: smb3_query_info_enter: xid=15 sid=0xd2d00587 tid=0xb5441939 fid=0x99896e72 class=0 type=0x3
  getcifsacl-24149 [005] .... 27854.761730: smb3_query_info_done: xid=15 sid=0xd2d00587 tid=0xb5441939 fid=0x99896e72 class=0 type=0x3
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Add tracepoint before sending an SMB3 command on the wire (ie add
an smb3_cmd_enter tracepoint). This allows us to look in much
more detail at response times (between request and response).
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Add dynamic trace point for open_enter (and posix mkdir enter)
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

When ENODATA returned we weren't logging the read completion
(not an error, but can be indicated by logging length 0) which
makes looking at read traces confusing for smb3.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Allows tracing begin (not just completion) of read, write
and query_dir which may be helpful in finding slow requests
and other timing information
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Adds two tracepoints - one for query_dir done (no err) and one for query_dir_err

Sanple output:

To start the trace in one window:
       trace-cmd record -e smb3_query_dir*

Then in another window after doing an
       ls /mnt

View the trace output by:

        trace-cmd show

Sample output:

           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
              | |       |   ||||       |         |
             ls-24869 [007] .... 90695.452009: smb3_query_dir_done: xid=7 sid=0x5027d24d tid=0xb95cf25a fid=0xc41a8c3e offset=0x0 len=0x16
             ls-24869 [000] .... 90695.452764: smb3_query_dir_done: xid=8 sid=0x5027d24d tid=0xb95cf25a fid=0xc41a8c3e offset=0x0 len=0x0
             ls-24874 [003] .... 90701.506342: smb3_query_dir_done: xid=11 sid=0x5027d24d tid=0xb95cf25a fid=0x33ad3601 offset=0x0 len=0x8
             ls-24874 [003] .... 90701.506917: smb3_query_dir_done: xid=12 sid=0x5027d24d tid=0xb95cf25a fid=0x33ad3601 offset=0x0 len=0x0
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

POSIX negotiate context now includes the GUID specifying
which POSIX open context we support.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NJeremy Allison <jra@samba.org>

    To 2.18
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we get one credit per compound part of the request
individually. This may lead to being stuck on waiting for credits
if multiple compounded operations happen in parallel. Try acquire
credits for all compound parts at once. Return immediately if not
enough credits and too few requests are in flight currently thus
narrowing the possibility of infinite waiting for credits.

The more advance fix is to return right away if not enough credits
for the compound request and do not look at the number of requests
in flight. The caller should handle such situations by falling back
to sequential execution of SMB commands instead of compounding.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Now we just return NULL cifsFileInfo pointer in cases we didn't find
or couldn't reopen a file. This hides errors from cifs_reopen_file()
especially retryable errors which should be handled appropriately.
Create new cifs_get_writable_file() routine that returns error codes
from cifs_reopen_file() and use it in the writeback codepath.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we check for an open file existence in wdata_send_pages()
which doesn't provide an easy way to handle error codes that will
be returned from find_writable_filehandle() once it is changed.
Move the check to writepages.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently wdata_send_pages() unlocks pages after sending.
This complicates further refactoring and doesn't align
with the function name. Move unlocking to writepages.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Reorder finding and reopening a writable handle file and getting
MTU credits in writepages because we may be stuck on low credits
otherwise.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we get MTU credits before we check an open file if
it needs to be reopened. Reopening the file in such conditions
leads to a possibility of being stuck waiting indefinitely
for credits in the transport layer. Fix this by reopening the
file first if needed and then getting MTU credits for async IO.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we do proper accounting for credits in regards to
reconnects and error handling, thus we do not need custom
credit adjustments when reconnect is detected developed
previously.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we adjust MTU credits before sending an IO request
and after reopening a file. This approach doesn't allow the
reopen routine to use existing credits that are not needed
for IO. Reorder credit adjustment and reopening a file to
use credits available to the client more efficiently. Also
unwrap complex if statement into few pieces to improve
readability.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

The reconnect might have happended after we obtained credits
and before we acquired srv_mutex. Check for that under the mutex
and retry a sync operation if the reconnect is detected.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

The reconnect might have happended after we obtained credits
and before we acquired srv_mutex. Check for that under the mutex
and retry an async operation if the reconnect is detected.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Every time after a session reconnect we don't need to account for
credits obtained in previous sessions. Make use of the recently
added cifs_credits structure to properly calculate credits for
non-MTU requests the same way we did for MTU ones.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Every time after a session reconnect we don't need to account for
credits obtained in previous sessions. Introduce new struct cifs_credits
which contains both credits value and reconnect instance of the
time those credits were taken. Modify a routine that add credits
back to handle the reconnect instance by assuming zero credits
if the reconnect happened after the credits were obtained and
before we decided to add them back due to some errors during sending.

This patch fixes the MTU credits cases. The subsequent patch
will handle non-MTU ones.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we set reconnect instance to zero on the first
connection but this is not convenient because we need to
reserve some special value for credit handling on reconnects
which is coming in subsequent patches. Fix this by starting
with one when initiating a new TCP connection.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

There are a couple places where we still account for 4 bytes
in the beginning of SMB2 packet which is not true in the current
code. Fix this to use a header preamble size where possible.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Even if a response is malformed, we should count credits
granted by the server to avoid miscalculations and unnecessary
reconnects due to client or server bugs. If the response has
been received partially, the session will be reconnected anyway
on the next iteration of the demultiplex thread, so counting
credits for such cases shouldn't break things.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we only skip credits logging on reconnects. When
unmounting a share the number of credits on the client doesn't
matter, so skip logging in such cases too.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Currently we skip setting a read error to -EIO if a stored
result is -ENODATA and a response hasn't been received. With
the recent changes in read error processing there shouldn't be
cases when -ENODATA is set without a response from the server,
so reset the error to -EIO unconditionally.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>