There is at least one suspected bug in crediting changes in cifs.ko
which has come up a few times in the discussions and in a customer
case.

This change adds tracepoints to the code which modifies the server
credit values in any way. The goal is to be able to track the changes
to the credit values of the session to be able to catch when there is
a crediting bug.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Also make sure these are displayed in /proc/mounts
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>

* extract_hostname() and extract_sharename() never return NULL, so
  use IS_ERR() instead of IS_ERR_OR_NULL() in cifs_find_swn_reg(). If
  any of these functions return an error, then return an error pointer
  instead of NULL.
* Change cifs_find_swn_reg() function to always return a valid pointer
  or an error pointer, instead of returning NULL if the registration
  is not found.
* Finally update cifs_find_swn_reg() callers to check for -EEXIST
  instead of NULL.
* In cifs_get_swn_reg() the swnreg idr mutex was not unlocked in the
  error path of cifs_find_swn_reg() call.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

warn_once when using the witness protocol that it is experimental
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>

This is needed so that we display the correct //server/share vs
\\server\share in /proc/mounts for the device name (in the new
mount API).
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>

Addresses an issue noted by the kernel test robot
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>

Many mount flags (e.g. for noperm, noxattr, nobrl,
cifsacl, mfsymlinks and more) can be updated now.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

This function will set/clear flags that can be changed during mount or remount
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

There is no need to load the default nls to check if the iocharset argument
was specified or not since we have it in cifs_sb->ctx
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

just use the one that is already available in ctx
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Only load/unload local_nls from cifs_sb and just make the ctx
contain a pointer to cifs_sb->ctx.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

and rename it to smb3_cleanup_fs_context[_content]
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Add missing sentinel to smb3_fs_parameters. This fixes ARM32 kernel
crashing once CIFS is registered.

 Unable to handle kernel paging request at virtual address 33626d73
...
 (strcmp) from (fs_validate_description)
 (fs_validate_description) from (register_filesystem)
 (register_filesystem) from (init_cifs [cifs])
 (init_cifs [cifs]) from (do_one_initcall)
 (do_one_initcall) from (do_init_module)
 (do_init_module) from (load_module)
 (load_module) from (sys_finit_module)
 (sys_finit_module) from (ret_fast_syscal)

Fixes: e07724d1cf38 ("cifs: switch to new mount api")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

This message is sent to tell a client to close its current connection
and connect to the specified address.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Can now be accessed via the ctx
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

We can already access these from cifs_sb->ctx so we no longer need
a local copy in cifs_sb.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Correct some trivial warnings caused when new file unc.c
was created. For example:

   In file included from fs/cifs/unc.c:11:
>> fs/cifs/cifsproto.h:44:28: warning: 'struct TCP_Server_Info' declared inside parameter list will not be visible outside of this definition or declaration
      44 | extern int smb_send(struct TCP_Server_Info *, struct smb_hdr *,
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

When compiling with W=1 I noticed various functions that
did not follow proper style in describing (in the comments)
the parameters passed in to the function. For example:

fs/cifs/inode.c:2236: warning: Function parameter or member 'mode' not described in 'cifs_wait_bit_killable'

I did not address the style warnings in two of the six files
(connect.c and misc.c) in order to reduce risk of merge
conflict with pending patches. We can update those later.
Signed-off-by: Steve French <stfrench@microsoft.com>

Some witness notifications, like client move, tell the client to
reconnect to a specific IP address. In this situation the DFS failover
code path has to be skipped so clean up as much as possible the
cifs_reconnect() code.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

If the daemon starts after mounting a share, or if it crashes, this
provides a mechanism to register again.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

+ Indicate if witness feature is supported
+ Indicate if witness is used when dumping tcons
+ Dumps witness registrations. Example:
  Witness registrations:
  Id: 1 Refs: 1 Network name: 'fs.fover.ad'(y) Share name: 'share1'(y) \
    Ip address: 192.168.103.200(n)
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

+ Set a handler for the witness notification messages received from the
  userspace daemon.

+ Handle the resource state change notification. When the resource
  becomes unavailable or available set the tcp status to
  CifsNeedReconnect for all channels.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

+ Define the generic netlink family commands and message attributes to
  communicate with the userspace daemon

+ The register and unregister commands are sent when connecting or
  disconnecting a tree. The witness registration keeps a pointer to
  the tcon and has the same lifetime.

+ Each registration has an id allocated by an IDR. This id is sent to the
  userspace daemon in the register command, and will be included in the
  notification messages from the userspace daemon to retrieve from the
  IDR the matching registration.

+ The authentication information is bundled in the register message.
  If kerberos is used the message just carries a flag.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Correct references to fs/cifs/README which has been replaced by
Documentation/filesystems/admin-guide/cifs/usage.rst, and also
correct a typo.
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Add 'witness' mount option to register for witness notifications.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Register a new generic netlink family to talk to the witness service
userspace daemon.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

misc.c was getting a little large, move two of the UNC parsing relating
functions to a new C file unc.c which makes the coding of the
upcoming witness protocol patch series a little cleaner as well.
Suggested-by: Rafal Szczesniak <rafal@elbingbrewery.org>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Trivial fix for a few comments which didn't follow kernel style
Signed-off-by: Steve French <stfrench@microsoft.com>

Move the function to misc.c
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

Move the function to misc.c and give it a public header.
Signed-off-by: Samuel Cabrero <scabrero@suse.de>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

as we now have a full smb3_fs_context as part of the cifs superblock
we no longer need a local copy of the mount options and can just
reference the copy in the smb3_fs_context.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

and populate it during mount in cifs_smb3_do_mount()
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

none of the callers use this argument any more.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

See Documentation/filesystems/mount_api.rst for details on new mount API
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>