struct file_lock is pretty large, so we really don't want that on the
stack in a potentially long call chain. Reorganize the arguments to
CIFSSMBPosixLock to eliminate the need for that.

Eliminate the get_flag and simply use a non-NULL pLockInfo to indicate
that this is a "get" operation. In order to do that, need to add a new
loff_t argument for the start_offset.
Reported-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Those macros add a newline on their own, so there's not any need to
embed one in the message itself.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Signed-off-by: NPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

when cifs_reconnect sets maxBuf to 0 and we try to calculate a size
of memory we need to store locks.
Signed-off-by: NPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

While traversing the linked list of open file handles, if the identfied
file handle is invalid, a reopen is attempted and if it fails, we
resume traversing where we stopped and cifs can oops while accessing
invalid next element, for list might have changed.

So mark the invalid file handle and attempt reopen if no
valid file handle is found in rest of the list.
If reopen fails, move the invalid file handle to the end of the list
and start traversing the list again from the begining.
Repeat this four times before giving up and returning an error if
file reopen keeps failing.

Cc: <stable@vger.kernel.org>
Signed-off-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>

to handle SMB2 lock type field further.
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>

CIFS brlock cache can be used by several file handles if we have a
write-caching lease on the file that is supported by SMB2 protocol.
Prepate the code to handle this situation correctly by sorting brlocks
by a fid to easily push them in portions when lease break comes.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>

Convert cifs_iovec_read to use async I/O. This also raises the limit on
the rsize for uncached reads. We first allocate a set of pages to hold
the replies, then issue the reads in parallel and then collect the
replies and copy the results into the iovec.

A possible future optimization would be to kmap and inline the iovec
buffers and read the data directly from the socket into that. That would
require some rather complex conversion of the iovec into a kvec however.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

We'll need this same bit of code for the uncached case.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

This isn't strictly necessary for the async readpages code, but the
uncached version will need to be able to collect the replies after
issuing the calls. Add a kref to cifs_readdata and use change the
code to take and put references appropriately.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

Cached and uncached reads will need to do different things here to
handle the difference when the pages are in pagecache and not. Abstract
out the function that marshals the page list into a kvec array.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

We'll need different completion routines for an uncached read. Allow
the caller to set the one he needs at allocation time. Also, move
most of these functions to file.c so we can make more of them static.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

In the recent update of the cifs_iovec_write code to use async writes,
the handling of the file position was broken. That patch added a local
"offset" variable to handle the offset, and then only updated the
original "*poffset" before exiting.

Unfortunately, it copied off the original offset from the beginning,
instead of doing so after generic_write_checks had been called. Fix
this by moving the initialization of "offset" after that in the
function.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

We can deadlock if we have a write oplock and two processes
use the same file handle. In this case the first process can't
unlock its lock if the second process blocked on the lock in the
same time.

Fix it by using posix_lock_file rather than posix_lock_file_wait
under cinode->lock_mutex. If we request a blocking lock and
posix_lock_file indicates that there is another lock that prevents
us, wait untill that lock is released and restart our call.

Cc: stable@kernel.org
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Revert previous version of patch to incorporate feedback
so that we can merge version 3 of the patch instead.w

This reverts commit b5efb978.

We can deadlock if we have a write oplock and two processes
use the same file handle. In this case the first process can't
unlock its lock if another process blocked on the lock in the
same time.

Fix this by removing lock_mutex protection from waiting on a
blocked lock and protect only posix_lock_file call.

Cc: stable@kernel.org
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>

Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>

cifs_update_eof has the potential to be racy if multiple threads are
trying to modify it at the same time. Protect modifications of the
server_eof value with the inode->i_lock.
Signed-off-by: NJeff Layton <jlayton@redhat.com>

We'll need to do something a bit different depending on the caller.
Abstract the code that marshals the page array into an iovec.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>

Use DIV_ROUND_UP. Also, PAGE_SIZE is more appropriate here since these
aren't pagecache pages.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>

The gfp flags are currently set to __GPF_HIGHMEM, which doesn't allow
for any reclaim. Make this more resilient by or'ing that with
GFP_KERNEL. Also, get rid of the goto and unify the exit codepath.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NPavel Shilovsky <piastry@etersoft.ru>

We'll need a different set of write completion ops when not writing out
of the pagecache.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>

We'll need this to handle rwpidforward option correctly when we use
async writes in the aio_write op.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NPavel Shilovsky <piastry@etersoft.ru>

Some servers sets this value less than 50 that was hardcoded and
we lost the connection if when we exceed this limit. Fix this by
respecting this value - not sending more than the server allows.

Cc: stable@kernel.org
Reviewed-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <stevef@smf-gateway.(none)>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Reported-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NSteve French <stevef@smf-gateway.(none)>

Reorganize the code to make the memory already allocated before
spinlock'ed loop.

Cc: stable@vger.kernel.org
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Reorder parms of cifs_lock_init, trivially simplify getlk code and
remove extra {} in cifs_lock_add_if.

Cc: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Now we allocate a lock structure at first, then we request to the server
and save the lock if server returned OK though void function - it prevents
the situation when we locked a file on the server and then return -ENOMEM
from setlk.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Request to the cache in FL_POSIX case only.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <smfrench@gmail.com>

to prevent the mutex being unlocked twice if we interrupt a blocked lock.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <smfrench@gmail.com>

that reduces a traffic and increases a performance.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

that reduces a traffic and increases a performance.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

to handle all lock requests on the client in an exclusive oplock case.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

If we have an oplock and negotiate mandatory locking style we handle
all brlock requests on the client.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Acked-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>