On async reads, page data is allocated before sending. When the
response is received but it has no data to fill (e.g.
STATUS_END_OF_FILE), __calc_signature() will still include the pages in
its computation, leading to an invalid signature check.
This patch fixes this by not setting the async read smb_rqst page data
(zeroed by default) if its got_bytes is 0.
This can be reproduced/verified with xfstests generic/465.
Cc: <stable@vger.kernel.org>
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Make sure to free cifs_ses::auth_key.response before allocating it as
we might end up leaking memory in reconnect or mounting.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
If session setup failed with kerberos auth, we ended up freeing
cifs_ses::auth_key.response twice in SMB2_auth_kerberos() and
sesInfoFree().
Fix this by zeroing out cifs_ses::auth_key.response after freeing it
in SMB2_auth_kerberos().
Fixes: a4e430c8c8 ("cifs: replace kfree() with kfree_sensitive() for sensitive data")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Serialise access of TCP_Server_Info::hostname in
assemble_neg_contexts() by holding the server's mutex otherwise it
might end up accessing an already-freed hostname pointer from
cifs_reconnect() or cifs_resolve_server().
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
Change notification is a commonly supported feature by most servers,
but the current ioctl to request notification when a directory is
changed does not return the information about what changed
(even though it is returned by the server in the SMB3 change
notify response), it simply returns when there is a change.
This ioctl improves upon CIFS_IOC_NOTIFY by returning the notify
information structure which includes the name of the file(s) that
changed and why. See MS-SMB2 2.2.35 for details on the individual
filter flags and the file_notify_information structure returned.
To use this simply pass in the following (with enough space
to fit at least one file_notify_information structure)
struct __attribute__((__packed__)) smb3_notify {
uint32_t completion_filter;
bool watch_tree;
uint32_t data_len;
uint8_t data[];
} __packed;
using CIFS_IOC_NOTIFY_INFO 0xc009cf0b
or equivalently _IOWR(CIFS_IOCTL_MAGIC, 11, struct smb3_notify_info)
The ioctl will block until the server detects a change to that
directory or its subdirectories (if watch_tree is set).
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Coverity spotted that we were not initalizing Stbz1 and Stbz2 to
zero in create_sd_buf.
Addresses-Coverity: 1513848 ("Uninitialized scalar variable")
Cc: <stable@vger.kernel.org>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Improve code readability by using existing macros:
Replace hardcoded alignment computations (e.g. (len + 7) & ~0x7) by
ALIGN()/IS_ALIGNED() macros.
Also replace (DIV_ROUND_UP(len, 8) * 8) with ALIGN(len, 8), which, if
not optimized by the compiler, has the overhead of a multiplication
and a division. Do the same for roundup() by replacing it by round_up()
(division-less version, but requires the multiple to be a power of 2,
which is always the case for us).
And remove some unnecessary checks where !IS_ALIGNED() would fit, but
calling round_up() directly is fine as it's a no-op if the value is
already aligned.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Prevent copying past @data buffer in smb2_validate_and_copy_iov() as
the output buffer in @iov might be potentially bigger and thus copying
more bytes than requested in @minbufsize.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Replace kfree with kfree_sensitive, or prepend memzero_explicit() in
other cases, when freeing sensitive material that could still be left
in memory.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reported-by: kernel test robot <oliver.sang@intel.com>
Link: https://lore.kernel.org/r/202209201529.ec633796-oliver.sang@intel.com
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Don't initialize the rc as its value is being overwritten before its
use.
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Needed this for debugging a failing xfstest.
Also change camel case for "treeName" to "tree_name" in tcon struct.
Example trace output (from "trace-cmd record -e smb3_tdis*"):
umount-9718 [006] ..... 5909.780244: smb3_tdis_enter: xid=206 sid=0xcf38894e tid=0x3d0b8cf8 path=\\localhost\test
umount-9718 [007] ..... 5909.780878: smb3_tdis_done: xid=206 sid=0xcf38894e tid=0x3d0b8cf8
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Commit d5c7076b77 ("smb3: add smb3.1.1 to default dialect list")
extend the dialects from 3 to 4, but forget to decrease the extended
length when specific the dialect, then the message length is larger
than expected.
This maybe leak some info through network because not initialize the
message body.
After apply this patch, the VALIDATE_NEGOTIATE_INFO message length is
reduced from 28 bytes to 26 bytes.
Fixes: d5c7076b77 ("smb3: add smb3.1.1 to default dialect list")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Cc: <stable@vger.kernel.org>
Acked-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In some cases of failure (dialect mismatches) in SMB2_negotiate(), after
the request is sent, the checks would return -EIO when they should be
rather setting rc = -EIO and jumping to neg_exit to free the response
buffer from mempool.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Since commit:
cifs: alloc_path_with_tree_prefix: do not append sep. if the path is empty
alloc_path_with_tree_prefix() function was no longer including the
trailing separator when @path is empty, although @out_len was still
assuming a path separator thus adding an extra byte to the final
filename.
This has caused mount issues in some Synology servers due to the extra
NULL byte in filenames when sending SMB2_CREATE requests with
SMB2_FLAGS_DFS_OPERATIONS set.
Fix this by checking if @path is not empty and then add extra byte for
separator. Also, do not include any trailing NULL bytes in filename
as MS-SMB2 requires it to be 8-byte aligned and not NULL terminated.
Cc: stable@vger.kernel.org
Fixes: 7eacba3b00 ("cifs: alloc_path_with_tree_prefix: do not append sep. if the path is empty")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.
Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
SMB2_ioctl() is always called with is_fsctl = true, so doesn't make any
sense to have it at all.
Thus, always set SMB2_0_IOCTL_IS_FSCTL flag on the request.
Also, as per MS-SMB2 3.3.5.15 "Receiving an SMB2 IOCTL Request", servers
must fail the request if the request flags is zero anyway.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
They are the same right now but tcon-> will later point to a different
type of struct containing a list of cfids.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Also rename crfid to cfid to have consistent naming for this variable.
This commit does not change any logic.
Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
DeleteMidQEntry() was just a proxy for cifs_mid_q_entry_release().
- remove DeleteMidQEntry()
- rename cifs_mid_q_entry_release() to release_mid()
- rename kref_put() callback _cifs_mid_q_entry_release to __release_mid
- rename AllocMidQEntry() to alloc_mid()
- rename cifs_delete_mid() to delete_mid()
Update callers to use new names.
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
During analysis of multichannel perf, it was seen that
the global locks cifs_tcp_ses_lock and GlobalMid_Lock, which
were shared between various data structures were causing a
lot of contention points.
With this change, we're breaking down the use of these locks
by introducing new locks at more granular levels. i.e.
server->srv_lock, ses->ses_lock and tcon->tc_lock to protect
the unprotected fields of server, session and tcon structs;
and server->mid_lock to protect mid related lists and entries
at server level.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Mount can now fail to older Samba servers due to a server
bug handling padding at the end of the last negotiate
context (negotiate contexts typically are rounded up to 8
bytes by adding padding if needed). This server bug can
be avoided by switching the order of negotiate contexts,
placing a negotiate context at the end that does not
require padding (prior to the recent netname context fix
this was the case on the client).
Fixes: 73130a7b1a ("smb3: fix empty netname context on secondary channels")
Reported-by: Julian Sikorski <belegdol@gmail.com>
Tested-by: Julian Sikorski <belegdol+github@gmail.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Some servers do not allow null netname contexts, which would cause
multichannel to revert to single channel when mounting to some
servers (e.g. Azure xSMB). The previous patch fixed that by avoiding
incorrectly sending the netname context when there would be a null
hostname sent in the netname context, while this patch fixes the null
hostname for the secondary channel by using the hostname of the
primary channel for the secondary channel.
Fixes: 4c14d7043f ("cifs: populate empty hostnames for extra channels")
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Some servers do not allow null netname contexts, which would cause
multichannel to revert to single channel when mounting to some
servers (e.g. Azure xSMB).
Fixes: 4c14d7043f ("cifs: populate empty hostnames for extra channels")
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
In order to debug problems with file size being reported incorrectly
temporarily (in this case xfstest generic/584 intermittent failure)
we need to add trace point for the non-compounded code path where
we set the file size (SMB2_set_eof). The new trace point is:
"smb3_set_eof"
Here is sample output from the tracepoint:
TASK-PID CPU# ||||| TIMESTAMP FUNCTION
| | | ||||| | |
xfs_io-75403 [002] ..... 95219.189835: smb3_set_eof: xid=221 sid=0xeef1cbd2 tid=0x27079ee6 fid=0x52edb58c offset=0x100000
aio-dio-append--75418 [010] ..... 95219.242402: smb3_set_eof: xid=226 sid=0xeef1cbd2 tid=0x27079ee6 fid=0xae89852d offset=0x0
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
During reconnects, we check the return value from
cifs_negotiate_protocol, and have handlers for both success
and failures. But if that passes, and cifs_setup_session
returns any errors other than -EACCES, we do not handle
that. This fix adds a handler for that, so that we don't
go ahead and try a tree_connect on a failed session.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
The srv_mutex is used during writeback so cifs should ensure that
allocations done when that mutex is held are done with GFP_NOFS, to
avoid having direct reclaim ending up waiting for the same mutex and
causing a deadlock. This is detected by lockdep with the splat below:
======================================================
WARNING: possible circular locking dependency detected
5.18.0 #70 Not tainted
------------------------------------------------------
kswapd0/49 is trying to acquire lock:
ffff8880195782e0 (&tcp_ses->srv_mutex){+.+.}-{3:3}, at: compound_send_recv
but task is already holding lock:
ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire
kmem_cache_alloc_trace
__request_module
crypto_alg_mod_lookup
crypto_alloc_tfm_node
crypto_alloc_shash
cifs_alloc_hash
smb311_crypto_shash_allocate
smb311_update_preauth_hash
compound_send_recv
cifs_send_recv
SMB2_negotiate
smb2_negotiate
cifs_negotiate_protocol
cifs_get_smb_ses
cifs_mount
cifs_smb3_do_mount
smb3_get_tree
vfs_get_tree
path_mount
__x64_sys_mount
do_syscall_64
entry_SYSCALL_64_after_hwframe
-> #0 (&tcp_ses->srv_mutex){+.+.}-{3:3}:
__lock_acquire
lock_acquire
__mutex_lock
mutex_lock_nested
compound_send_recv
cifs_send_recv
SMB2_write
smb2_sync_write
cifs_write
cifs_writepage_locked
cifs_writepage
shrink_page_list
shrink_lruvec
shrink_node
balance_pgdat
kswapd
kthread
ret_from_fork
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&tcp_ses->srv_mutex);
lock(fs_reclaim);
lock(&tcp_ses->srv_mutex);
*** DEADLOCK ***
1 lock held by kswapd0/49:
#0: ffffffffa98e66c0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat
stack backtrace:
CPU: 2 PID: 49 Comm: kswapd0 Not tainted 5.18.0 #70
Call Trace:
<TASK>
dump_stack_lvl
dump_stack
print_circular_bug.cold
check_noncircular
__lock_acquire
lock_acquire
__mutex_lock
mutex_lock_nested
compound_send_recv
cifs_send_recv
SMB2_write
smb2_sync_write
cifs_write
cifs_writepage_locked
cifs_writepage
shrink_page_list
shrink_lruvec
shrink_node
balance_pgdat
kswapd
kthread
ret_from_fork
</TASK>
Fix this by using the memalloc_nofs_save/restore APIs around the places
where the srv_mutex is held. Do this in a wrapper function for the
lock/unlock of the srv_mutex, and rename the srv_mutex to avoid missing
call sites in the conversion.
Note that there is another lockdep warning involving internal crypto
locks, which was masked by this problem and is visible after this fix,
see the discussion in this thread:
https://lore.kernel.org/all/20220523123755.GA13668@axis.com/
Link: https://lore.kernel.org/r/CANT5p=rqcYfYMVHirqvdnnca4Mo+JQSw5Qu12v=kPfpk5yhhmg@mail.gmail.com/
Reported-by: Shyam Prasad N <nspmangalore@gmail.com>
Suggested-by: Lars Persson <larper@axis.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
ses->status today shares statusEnum with server->tcpStatus.
This has been confusing, and tcon->status has deviated to use
a new enum. Follow suit and use new enum for ses_status as well.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Recent changes to multichannel to allow channel reconnects to
work in parallel and independent of each other did so by
making use of tcpStatus for the connection, and status for the
session. However, this did not take into account the multiuser
scenario, where same connection is used by multiple connections.
However, tcpStatus should be tracked only till the end of
negotiate exchange, and not used for session setup. This change
fixes this.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Currently the way the tid (tree connection) status is tracked
is confusing. The same enum is used for structs cifs_tcon
and cifs_ses and TCP_Server_info, but each of these three has
different states that they transition among. The current
code also unnecessarily uses camelCase.
Convert from use of statusEnum to a new tid_status_enum for
tree connections. The valid states for a tid are:
TID_NEW = 0,
TID_GOOD,
TID_EXITING,
TID_NEED_RECON,
TID_NEED_TCON,
TID_IN_TCON,
TID_NEED_FILES_INVALIDATE, /* unused, considering removing in future */
TID_IN_FILES_INVALIDATE
It also removes CifsNeedTcon, CifsInTcon, CifsNeedFilesInvalidate and
CifsInFilesInvalidate from the statusEnum used for session and
TCP_Server_Info since they are not relevant for those.
A follow on patch will fix the places where we use the
tcon->need_reconnect flag to be more consistent with the tid->status.
Also fixes a bug that was:
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The bug is here:
if (!tcon) {
resched = true;
list_del_init(&ses->rlist);
cifs_put_smb_ses(ses);
Because the list_for_each_entry() never exits early (without any
break/goto/return inside the loop), the iterator 'ses' after the
loop will always be an pointer to a invalid struct containing the
HEAD (&pserver->smb_ses_list). As a result, the uses of 'ses' above
will lead to a invalid memory access.
The original intention should have been to walk each entry 'ses' in
'&tmp_ses_list', delete '&ses->rlist' and put 'ses'. So fix it with
a list_for_each_entry_safe().
Cc: stable@vger.kernel.org # 5.17
Fixes: 3663c9045f ("cifs: check reconnects for channels of active tcons too")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The client used to partially convert the fids to le64, while storing
or sending them by using host endianness. This broke the client on
big-endian machines. Instead of converting them to le64, store them
as opaque integers and then avoid byteswapping when sending them over
wire.
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
For improved debugging it can be helpful to send version information
as other clients do during NTLMSSP negotiation. See protocol document
MS-NLMP section 2.2.1.1
Set the major and minor versions based on the kernel version, and the
BuildNumber based on the internal cifs.ko module version number,
and following the recommendation in the protocol documentation
(MS-NLMP section 2.2.10) we set the NTLMRevisionCurrent field to 15.
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
The status of tcp session, smb session and tcon have the
same flow, irrespective of the SMB version used. Hence
these status checks and updates should happen in the
version independent callers of these commands.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
ses_selected is being declared and set at several places. It is not
being used. Remove it.
Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
A spin lock called chan_lock was introduced recently.
But not all accesses were protected. Doing that with
this change.
To make sure that a channel is not freed when in use,
we need to introduce a ref count. But today, we don't
ever free channels.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Recent changes to multichannel required some adjustments in
the way connection states transitioned during/after reconnect.
Also some minor fixes:
1. A pending switch of GlobalMid_Lock to cifs_tcp_ses_lock
2. Relocations of the code that logs reconnect
3. Changed some code in allocate_mid to suit the new scheme
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
With the new multichannel logic, when a channel needs reconnection,
the tree connect and other channels can still be active.
This fix will handle cases of checking for channel reconnect,
when the tcon does not need reconnect.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
alloc_path_with_tree_prefix() concatenates tree prefix and the path.
Windows CIFS client does not add separator after the tree prefix if the path
is empty. Let's do the same.
This fixes mounting DFS namespaces with names containing non-ASCII symbols.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215440
Signed-off-by: Eugene Korenevsky <ekorenevsky@astralinux.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
When a TCP connection gets reestablished by the sender in cifs_reconnect,
There is a chance for race condition with demultiplex thread waiting in
cifs_readv_from_socket on the old socket. It will now return -ECONNRESET.
This condition is handled by comparing socket pointer before and after
sock_recvmsg. If the socket pointer has changed, we should not call
cifs_reconnect again, but instead retry with new socket.
Also fixed another bug in my prev mchan commits.
We should always reestablish session (even if binding) on a channel
that needs reconnection.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
If functions like cifs_negotiate_protocol, cifs_setup_session,
cifs_tree_connect are called in parallel on different channels,
each of these will be execute the requests. This maybe unnecessary
in some cases, and only the first caller may need to do the work.
This is achieved by having more states for the tcp/smb/tcon session
status fields. And tracking the state of reconnection based on the
state machine.
For example:
for tcp connections:
CifsNew/CifsNeedReconnect ->
CifsNeedNegotiate ->
CifsInNegotiate ->
CifsNeedSessSetup ->
CifsInSessSetup ->
CifsGood
for smb sessions:
CifsNew/CifsNeedReconnect ->
CifsGood
for tcon:
CifsNew/CifsNeedReconnect ->
CifsInFilesInvalidate ->
CifsNeedTcon ->
CifsInTcon ->
CifsGood
If any channel reconnect sees that it's in the middle of
transition to CifsGood, then they can skip the function.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
While checking/updating status for tcp ses, smb ses or tcon,
we take GlobalMid_Lock. This doesn't make any sense.
Replaced it with cifs_tcp_ses_lock.
Ideally, we should take a spin lock per struct.
But since tcp ses, smb ses and tcon objects won't add up to a lot,
I think there should not be too much contention.
Also, in few other places, these are checked without locking.
Added locking for these.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We use the concept of "binding" when one of the secondary channel
is in the process of connecting/reconnecting to the server. Till this
binding process completes, and the channel is bound to an existing session,
we redirect traffic from other established channels on the binding channel,
effectively blocking all traffic till individual channels get reconnected.
With my last set of commits, we can get rid of this binding serialization.
We now have a bitmap of connection states for each channel. We will use
this bitmap instead for tracking channel status.
Having a bitmap also now enables us to keep the session alive, as long
as even a single channel underneath is alive.
Unfortunately, this also meant that we need to supply the tcp connection
info for the channel during all negotiate and session setup functions.
These changes have resulted in a slightly bigger code churn.
However, I expect perf and robustness improvements in the mchan scenario
after this change.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
We needed a way to identify the channels under the smb session
which are in reconnect, so that the traffic to other channels
can continue. So I replaced the bool need_reconnect with
a bitmask identifying all the channels that need reconnection
(named chans_need_reconnect). When a channel needs reconnection,
the bit corresponding to the index of the server in ses->chans
is used to set this bitmask. Checking if no channels or all
the channels need reconnect then becomes very easy.
Also wrote some helper macros for checking and setting the bits.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
It is clearer to initialize rc at the beginning of the function.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Today, we don't have any way to get the smb session for any
of the secondary channels. Introducing a pointer to the primary
server from server struct of any secondary channel. The value will
be NULL for the server of the primary channel. This will enable us
to get the smb session for any channel.
This will be needed for some of the changes that I'm planning
to make soon.
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely for it to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1437501 ("Explicit Null dereference")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Although unlikely to be possible for rsp to be null here,
the check is safer to add, and quiets a Coverity warning.
Addresses-Coverity: 1420428 ("Explicit null dereferenced")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
