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* Prepare for encryption support (first part). Add decryption and encryption ↵Steve French2016-01-141-1/+1
| | | | | | | key generation. Thanks to Metze for helping with this. Reviewed-by: Stefan Metzmacher <metze@samba.org> Signed-off-by: Steve French <steve.french@primarydata.com>
* VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells2015-04-151-1/+1
| | | | | | | that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* cifs: convert to print_hex_dump() instead of custom implementationAndy Shevchenko2014-12-071-30/+2
| | | | | | | | | | | | | This patch converts custom dumper to use native print_hex_dump() instead. The cifs_dump_mem() will have an offsets per each line which differs it from the original code. In the dump_smb() we may use native print_hex_dump() as well. It will show slightly different output in ASCII part when character is unprintable, otherwise it keeps same structure. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steve French <steve.french@primarydata.com>
* cifs: remove unused function cifs_oplock_break_waitVincent Stehlé2014-08-111-7/+0
| | | | | | | | | | | | | | Commit 743162013d40 ("sched: Remove proliferation of wait_on_bit() action functions") has removed the call to cifs_oplock_break_wait, making this function unused; remove it. This fixes the following compilation warning: fs/cifs/misc.c:578:1: warning: ‘cifs_oplock_break_wait’ defined but not used [-Wunused-function] Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> Cc: Steve French <sfrench@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
* Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2014-08-091-2/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull CIFS updates from Steve French: "The most visible change in this set is the additional of multi-credit support for SMB2/SMB3 which dramatically improves the large file i/o performance for these dialects and significantly increases the maximum i/o size used on the wire for SMB2/SMB3. Also reconnection behavior after network failure is improved" * 'for-next' of git://git.samba.org/sfrench/cifs-2.6: (35 commits) Add worker function to set allocation size [CIFS] Fix incorrect hex vs. decimal in some debug print statements update CIFS TODO list Add Pavel to contributor list in cifs AUTHORS file Update cifs version CIFS: Fix STATUS_CANNOT_DELETE error mapping for SMB2 CIFS: Optimize readpages in a short read case on reconnects CIFS: Optimize cifs_user_read() in a short read case on reconnects CIFS: Improve indentation in cifs_user_read() CIFS: Fix possible buffer corruption in cifs_user_read() CIFS: Count got bytes in read_into_pages() CIFS: Use separate var for the number of bytes got in async read CIFS: Indicate reconnect with ECONNABORTED error code CIFS: Use multicredits for SMB 2.1/3 reads CIFS: Fix rsize usage for sync read CIFS: Fix rsize usage in user read CIFS: Separate page reading from user read CIFS: Fix rsize usage in readpages CIFS: Separate page search from readpages CIFS: Use multicredits for SMB 2.1/3 writes ...
| * [CIFS] Fix incorrect hex vs. decimal in some debug print statementsSteve French2014-08-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | Joe Perches and Hans Wennborg noticed that various places in the kernel were printing decimal numbers with 0x prefix. printk("0x%d") or equivalent This fixes the instances of this in the cifs driver. CC: Hans Wennborg <hans@hanshq.net> CC: Joe Perches <joe@perches.com> Signed-off-by: Steve French <smfrench@gmail.com>
| * cifs: replace code with free_rsp_buf()Sachin Prabhu2014-07-311-0/+9
| | | | | | | | | | | | | | | | | | The functionality provided by free_rsp_buf() is duplicated in a number of places. Replace these instances with a call to free_rsp_buf(). Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com> Signed-off-by: Steve French <smfrench@gmail.com>
* | sched: Remove proliferation of wait_on_bit() action functionsNeilBrown2014-07-161-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current "wait_on_bit" interface requires an 'action' function to be provided which does the actual waiting. There are over 20 such functions, many of them identical. Most cases can be satisfied by one of just two functions, one which uses io_schedule() and one which just uses schedule(). So: Rename wait_on_bit and wait_on_bit_lock to wait_on_bit_action and wait_on_bit_lock_action to make it explicit that they need an action function. Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io which are *not* given an action function but implicitly use a standard one. The decision to error-out if a signal is pending is now made based on the 'mode' argument rather than being encoded in the action function. All instances of the old wait_on_bit and wait_on_bit_lock which can use the new version have been changed accordingly and their action functions have been discarded. wait_on_bit{_lock} does not return any specific error code in the event of a signal so the caller must check for non-zero and interpolate their own error code as appropriate. The wait_on_bit() call in __fscache_wait_on_invalidate() was ambiguous as it specified TASK_UNINTERRUPTIBLE but used fscache_wait_bit_interruptible as an action function. David Howells confirms this should be uniformly "uninterruptible" The main remaining user of wait_on_bit{,_lock}_action is NFS which needs to use a freezer-aware schedule() call. A comment in fs/gfs2/glock.c notes that having multiple 'action' functions is useful as they display differently in the 'wchan' field of 'ps'. (and /proc/$PID/wchan). As the new bit_wait{,_io} functions are tagged "__sched", they will not show up at all, but something higher in the stack. So the distinction will still be visible, only with different function names (gds2_glock_wait versus gfs2_glock_dq_wait in the gfs2/glock.c case). Since first version of this patch (against 3.15) two new action functions appeared, on in NFS and one in CIFS. CIFS also now uses an action function that makes the same freezer aware schedule call as NFS. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: David Howells <dhowells@redhat.com> (fscache, keys) Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2) Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown Signed-off-by: Ingo Molnar <mingo@kernel.org>
* cifs: Wait for writebacks to complete before attempting write.Sachin Prabhu2014-04-161-2/+72
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Problem reported in Red Hat bz 1040329 for strict writes where we cache only when we hold oplock and write direct to the server when we don't. When we receive an oplock break, we first change the oplock value for the inode in cifsInodeInfo->oplock to indicate that we no longer hold the oplock before we enqueue a task to flush changes to the backing device. Once we have completed flushing the changes, we return the oplock to the server. There are 2 ways here where we can have data corruption 1) While we flush changes to the backing device as part of the oplock break, we can have processes write to the file. These writes check for the oplock, find none and attempt to write directly to the server. These direct writes made while we are flushing from cache could be overwritten by data being flushed from the cache causing data corruption. 2) While a thread runs in cifs_strict_writev, the machine could receive and process an oplock break after the thread has checked the oplock and found that it allows us to cache and before we have made changes to the cache. In that case, we end up with a dirty page in cache when we shouldn't have any. This will be flushed later and will overwrite all subsequent writes to the part of the file represented by this page. Before making any writes to the server, we need to confirm that we are not in the process of flushing data to the server and if we are, we should wait until the process is complete before we attempt the write. We should also wait for existing writes to complete before we process an oplock break request which changes oplock values. We add a version specific downgrade_oplock() operation to allow for differences in the oplock values set for the different smb versions. Cc: stable@vger.kernel.org Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: Make big endian multiplex ID sequences monotonic on the wireTim Gardner2013-11-021-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The multiplex identifier (MID) in the SMB header is only ever used by the client, in conjunction with PID, to match responses from the server. As such, the endianess of the MID is not important. However, When tracing packet sequences on the wire, protocol analyzers such as wireshark display MID as little endian. It is much more informative for the on-the-wire MID sequences to match debug information emitted by the CIFS driver. Therefore, one should write and read MID in the SMB header assuming it is always little endian. Observed from wireshark during the protocol negotiation and session setup: Multiplex ID: 256 Multiplex ID: 256 Multiplex ID: 512 Multiplex ID: 512 Multiplex ID: 768 Multiplex ID: 768 After this patch on-the-wire MID values begin at 1 and increase monotonically. Introduce get_next_mid64() for the internal consumers that use the full 64 bit multiplex identifier. Introduce the helpers get_mid() and compare_mid() to make the endian translation clear. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Tim Gardner <timg@tpi.com> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: Remove redundant multiplex identifier check from check_smb_hdr()Tim Gardner2013-10-281-10/+2
| | | | | | | | | | The only call site for check_smb_header() assigns 'mid' from the SMB packet, which is then checked again in check_smb_header(). This seems like redundant redundancy. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Tim Gardner <timg@tpi.com> Signed-off-by: Steve French <smfrench@gmail.com>
* CIFS: Replace clientCanCache* bools with an integerPavel Shilovsky2013-09-081-8/+4
| | | | | | | that prepare the code to handle different types of SMB2 leases. Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: Process post session setup code in respective dialect functions.Shirish Pargaonkar2013-09-081-0/+1
| | | | | | | | | | | | | | | | | | | | | | | Move the post (successful) session setup code to respective dialect routines. For smb1, session key is per smb connection. For smb2/smb3, session key is per smb session. If client and server do not require signing, free session key for smb1/2/3. If client and server require signing smb1 - Copy (kmemdup) session key for the first session to connection. Free session key of that and subsequent sessions on this connection. smb2 - For every session, keep the session key and free it when the session is being shutdown. smb3 - For every session, generate the smb3 signing key using the session key and then free the session key. There are two unrelated line formatting changes as well. Reviewed-by: Jeff Layton <jlayton@samba.org> Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: track the enablement of signing in the TCP_Server_InfoJeff Layton2013-06-241-2/+1
| | | | | | | | | | | | | | | | | | | | | Currently, we determine this according to flags in the sec_mode, flags in the global_secflags and via other methods. That makes the semantics very hard to follow and there are corner cases where we don't handle this correctly. Add a new bool to the TCP_Server_Info that acts as a simple flag to tell us whether signing is enabled on this connection or not, and fix up the places that need to determine this to use that flag. This is a bit weird for the SMB2 case, where signing is per-session. SMB2 needs work in this area already though. The existing SMB2 code has similar logic to what we're using here, so there should be no real change in behavior. These changes should make it easier to implement per-session signing in the future though. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <smfrench@gmail.com>
* [CIFS] cifs: Rename cERROR and cFYI to cifs_dbgJoe Perches2013-05-041-41/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not obvious from reading the macro names that these macros are for debugging. Convert the names to a single more typical kernel style cifs_dbg macro. cERROR(1, ...) -> cifs_dbg(VFS, ...) cFYI(1, ...) -> cifs_dbg(FYI, ...) cFYI(DBG2, ...) -> cifs_dbg(NOISY, ...) Move the terminating format newline from the macro to the call site. Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the "CIFS VFS: " prefix for VFS messages. Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y) $ size fs/cifs/cifs.ko* text data bss dec hex filename 265245 2525 132 267902 4167e fs/cifs/cifs.ko.new 268359 2525 132 271016 422a8 fs/cifs/cifs.ko.old Other miscellaneous changes around these conversions: o Miscellaneous typo fixes o Add terminating \n's to almost all formats and remove them from the macros to be more kernel style like. A few formats previously had defective \n's o Remove unnecessary OOM messages as kmalloc() calls dump_stack o Coalesce formats to make grep easier, added missing spaces when coalescing formats o Use %s, __func__ instead of embedded function name o Removed unnecessary "cifs: " prefixes o Convert kzalloc with multiply to kcalloc o Remove unused cifswarn macro Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: Convert struct cifs_sb_info to use kuids and kgidsEric W. Biederman2013-02-131-1/+1
| | | | | Cc: Steve French <smfrench@gmail.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* CIFS: Fix fast lease break after open problemPavel Shilovsky2012-09-241-0/+30
| | | | | | | | | | | | Now we walk though cifsFileInfo's list for every incoming lease break and look for an equivalent there. That approach misses lease breaks that come just after an open response - we don't have time to populate new cifsFileInfo structure to the list. Fix this by adding new list of pending opens and look for a lease there if we didn't find it in the list of cifsFileInfo structures. Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>
* CIFS: Replace netfid with cifs_fid struct in cifsFileInfoPavel Shilovsky2012-09-241-1/+1
| | | | | | | | | | | | This is help us to extend the code for future protocols that can use another fid mechanism (as SMB2 that has it divided into two parts: persistent and violatile). Also rename variables and refactor the code around the changes. Reviewed-by: Jeff Layton <jlayton@samba.org> Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
* CIFS: Move clear/print_stats code to ops structPavel Shilovsky2012-07-241-1/+1
| | | | | Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
* CIFS: Respect SMB2 header/max header sizePavel Shilovsky2012-07-241-6/+19
| | | | | | | | Use SMB2 header size values for allocation and memset because they are bigger and suitable for both CIFS and SMB2. Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <smfrench@gmail.com>
* CIFS: Rename Get/FreeXid and make them work with unsigned intPavel Shilovsky2012-07-241-2/+2
| | | | | | Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <smfrench@gmail.com>
* CIFS: Move get_next_mid to ops structPavel Shilovsky2012-06-011-88/+1
| | | | | | Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org> Signed-off-by: Steve French <sfrench@us.ibm.com>
* CIFS: Move add/set_credits and get_credits_field to ops structurePavel Shilovsky2012-05-231-19/+0
| | | | | | | Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: remove legacy MultiuserMount optionJeff Layton2012-05-161-47/+0
| | | | | | We've now warned about this for two releases. Remove it for 3.5. Signed-off-by: Jeff Layton <jlayton@redhat.com>
* cifs: add new cifsiod_wq workqueueJeff Layton2012-03-231-1/+1
| | | | | | | | | | ...and convert existing cifs users of system_nrt_wq to use that instead. Also, make it freezable, and set WQ_MEM_RECLAIM since we use it to deal with write reply handling. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
* CIFS: Change mid_q_entry structure fieldsPavel Shilovsky2012-03-231-1/+1
| | | | | | | to be protocol-unspecific and big enough to keep both CIFS and SMB2 values. Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
* CIFS: Expand CurrentMid fieldPavel Shilovsky2012-03-231-38/+46
| | | | | | | | While in CIFS/SMB we have 16 bit mid, in SMB2 it is 64 bit. Convert the existing field to 64 bit and mask off higher bits for CIFS/SMB. Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
* CIFS: Separate protocol-specific code from demultiplex codePavel Shilovsky2012-03-231-2/+5
| | | | Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
* CIFS: Separate protocol-specific code from transport routinesPavel Shilovsky2012-03-231-3/+2
| | | | | | that lets us use this functions for SMB2. Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
* CIFS: Introduce credit-based flow controlPavel Shilovsky2012-03-211-0/+19
| | | | | | | | | | and send no more than credits value requests at once. For SMB/CIFS it's trivial: increment this value by receiving any message and decrement by sending one. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: Add mount options for backup intent (try #6)Shirish Pargaonkar2011-10-121-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | Add mount options backupuid and backugid. It allows an authenticated user to access files with the intent to back them up including their ACLs, who may not have access permission but has "Backup files and directories user right" on them (by virtue of being part of the built-in group Backup Operators. When mount options backupuid is specified, cifs client restricts the use of backup intents to the user whose effective user id is specified along with the mount option. When mount options backupgid is specified, cifs client restricts the use of backup intents to the users whose effective user id belongs to the group id specified along with the mount option. If an authenticated user is not part of the built-in group Backup Operators at the server, access to such files is denied, even if allowed by the client. Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: clean up checkSMBJeff Layton2011-10-121-26/+25
| | | | | | | | | | | | | | | | | The variable names in this function are so ambiguous that it's very difficult to know what it's doing. Rename them to make it a bit more clear. Also, remove a redundant length check. cifsd checks to make sure that the rfclen isn't larger than the maximum frame size when it does the receive. Finally, change checkSMB to return a real error code (-EIO) when it finds an error. That will help simplify some coming changes in the callers. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <smfrench@gmail.com>
* cifs: simplify refcounting for oplock breaksJeff Layton2011-07-311-9/+2
| | | | | | | | | | | | | | | | | Currently, we take a sb->s_active reference and a cifsFileInfo reference when an oplock break workqueue job is queued. This is unnecessary and more complicated than it needs to be. Also as Al points out, deactivate_super has non-trivial locking implications so it's best to avoid that if we can. Instead, just cancel any pending oplock breaks for this filehandle synchronously in cifsFileInfo_put after taking it off the lists. That should ensure that this job doesn't outlive the structures it depends on. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* [CIFS] Rename three structures to avoid camel caseSteve French2011-05-271-16/+16
| | | | | | | | | | secMode to sec_mode and cifsTconInfo to cifs_tcon and cifsSesInfo to cifs_ses Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: keep BCC in little-endian formatJeff Layton2011-05-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | This is the same patch as originally posted, just with some merge conflicts fixed up... Currently, the ByteCount is usually converted to host-endian on receive. This is confusing however, as we need to keep two sets of routines for accessing it, and keep track of when to use each routine. Munging received packets like this also limits when the signature can be calulated. Simplify the code by keeping the received ByteCount in little-endian format. This allows us to eliminate a set of routines for accessing it and we can now drop the *_le suffixes from the accessor functions since that's now implied. While we're at it, switch all of the places that read the ByteCount directly to use the get_bcc inline which should also clean up some unaligned accesses. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* consistently use smb_buf_length as be32 for cifs (try 3)Steve French2011-05-191-5/+3
| | | | | | | | | | | | | | | | | | | There is one big endian field in the cifs protocol, the RFC1001 length, which cifs code (unlike in the smb2 code) had been handling as u32 until the last possible moment, when it was converted to be32 (its native form) before sending on the wire. To remove the last sparse endian warning, and to make this consistent with the smb2 implementation (which always treats the fields in their native size and endianness), convert all uses of smb_buf_length to be32. This version incorporates Christoph's comment about using be32_add_cpu, and fixes a typo in the second version of the patch. Signed-off-by: Steve French <sfrench@us.ibm.com> Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: fix broken BCC check in is_valid_oplock_breakJeff Layton2011-04-121-1/+1
| | | | | | | | | The BCC is still __le16 at this point, and in any case we need to use the get_bcc_le macro to make sure we don't hit alignment problems. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* Allow user names longer than 32 bytesSteve French2011-04-121-0/+1
| | | | | | | | | We artificially limited the user name to 32 bytes, but modern servers handle larger. Set the maximum length to a reasonable 256, and make the user name string dynamically allocated rather than a fixed size in session structure. Also clean up old checkpatch warning. Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: fix length checks in checkSMBJeff Layton2011-01-311-16/+17
| | | | | | | | | | | | | | | | The cERROR message in checkSMB when the calculated length doesn't match the RFC1001 length is incorrect in many cases. It always says that the RFC1001 length is bigger than the SMB, even when it's actually the reverse. Fix the error message to say the reverse of what it does now when the SMB length goes beyond the end of the received data. Also, clarify the error message when the RFC length is too big. Finally, clarify the comments to show that the 512 byte limit on extra data at the end of the packet is arbitrary. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: force a reconnect if there are too many MIDs in flightJeff Layton2011-01-311-13/+24
| | | | | | | | | | | | | | | | | | | | | Currently, we allow the pending_mid_q to grow without bound with SIGKILL'ed processes. This could eventually be a DoS'able problem. An unprivileged user could a process that does a long-running call and then SIGKILL it. If he can also intercept the NT_CANCEL calls or the replies from the server, then the pending_mid_q could grow very large, possibly even to 2^16 entries which might leave GetNextMid in an infinite loop. Fix this by imposing a hard limit of 32k calls per server. If we cross that limit, set the tcpStatus to CifsNeedReconnect to force cifsd to eventually reconnect the socket and clean out the pending_mid_q. While we're at it, clean up the function a bit and eliminate an unnecessary NULL pointer check. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: simplify SMB header check routineJeff Layton2011-01-311-22/+24
| | | | | | | | ...just cleanup. There should be no behavior change. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Pavel Shilovsky <piastryyy@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: fix unaligned accesses in cifsConvertToUCSJeff Layton2011-01-201-71/+0
| | | | | | | | | | | | Move cifsConvertToUCS to cifs_unicode.c where all of the other unicode related functions live. Have it store mapped characters in 'temp' and then use put_unaligned_le16 to copy it to the target buffer. Also fix the comments to match kernel coding style. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Pavel Shilovsky <piastryyy@gmail.com> Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* CIFS: Fix oplock break handling (try #2)Pavel Shilovsky2011-01-191-1/+1
| | | | | | | | | | | | | | | When we get oplock break notification we should set the appropriate value of OplockLevel field in oplock break acknowledge according to the oplock level held by the client in this time. As we only can have level II oplock or no oplock in the case of oplock break, we should be aware only about clientCanCacheRead field in cifsInodeInfo structure. Also fix bug connected with wrong interpretation of OplockLevel field during oplock break notification processing. Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> Cc: <stable@kernel.org> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: make cifs_set_oplock_level() take a cifsInodeInfo pointerPavel Shilovsky2010-11-051-7/+9
| | | | | | | | All the callers already have a pointer to struct cifsInodeInfo. Use it. Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* CIFS: Add cifs_set_oplock_levelPavel Shilovsky2010-11-021-3/+20
| | | | | | | | Simplify many places when we need to set oplock level on an inode. Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: update comments - [s/GlobalSMBSesLock/cifs_file_list_lock/g]Suresh Jayaraman2010-10-251-1/+1
| | | | | | | GlobalSMBSesLock is now cifs_file_list_lock. Update comments to reflect this. Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
* [CIFS] move close processing from cifs_close to cifsFileInfo_putSteve French2010-10-211-10/+0
| | | | | | | | | | | | | | | | Now that it's feasible for a cifsFileInfo to outlive the filp under which it was created, move the close processing into cifsFileInfo_put. This means that the last user of the filehandle always does the actual on the wire close call. This also allows us to get rid of the closePend flag from cifsFileInfo. If we have an active reference to the file then it's never going to have a close pending. cifs_close is converted to simply put the filehandle. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: convert cifs_tcp_ses_lock from a rwlock to a spinlockSuresh Jayaraman2010-10-211-7/+7
| | | | | | | | | | | | | | cifs_tcp_ses_lock is a rwlock with protects the cifs_tcp_ses_list, server->smb_ses_list and the ses->tcon_list. It also protects a few ref counters in server, ses and tcon. In most cases the critical section doesn't seem to be large, in a few cases where it is slightly large, there seem to be really no benefit from concurrent access. I briefly considered RCU mechanism but it appears to me that there is no real need. Replace it with a spinlock and get rid of the last rwlock in the cifs code. Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: convert GlobalSMBSeslock from a rwlock to regular spinlockJeff Layton2010-10-181-4/+4
| | | | | | | | | | | | | | | | | | | | | Convert this lock to a regular spinlock A rwlock_t offers little value here. It's more expensive than a regular spinlock unless you have a fairly large section of code that runs under the read lock and can benefit from the concurrency. Additionally, we need to ensure that the refcounting for files isn't racy and to do that we need to lock areas that can increment it for write. That means that the areas that can actually use a read_lock are very few and relatively infrequently used. While we're at it, change the name to something easier to type, and fix a bug in find_writable_file. cifsFileInfo_put can sleep and shouldn't be called while holding the lock. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
* cifs: keep dentry reference in cifsFileInfo instead of inode referenceJeff Layton2010-10-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | cifsFileInfo is a bit problematic. It contains a reference back to the struct file itself. This makes it difficult for a cifsFileInfo to exist without a corresponding struct file. It would be better instead of the cifsFileInfo just held info pertaining to the open file on the server instead without any back refrences to the struct file. This would allow it to exist after the filp to which it was originally attached was closed. Much of the use of the file pointer in this struct is to get at the dentry. Begin divorcing the cifsFileInfo from the struct file by keeping a reference to the dentry. Since the dentry will have a reference to the inode, we can eliminate the "pInode" field too and convert the igrab/iput to dget/dput. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Suresh Jayaraman <sjayaraman@suse.de> Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com> Signed-off-by: Steve French <sfrench@us.ibm.com>