Just the lookup flags.  Die, bastard, die...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

namely, 1 ;-)  That's what we want to return from ->atomic_open()
instances after finish_no_open().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Just pass struct file *.  Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int.  Next: saner prototypes for parts in
namei.c
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and let finish_open() report having opened the file via that sucker.
Next step: don't modify od->filp at all.

[AV: FILE_CREATE was already used by cifs; Miklos' fix folded]
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add an ->atomic_open implementation which replaces the atomic lookup+open+create
operation implemented via ->lookup and ->create operations.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
CC: Steve French <sfrench@samba.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

When revalidating a dentry, if the inode wasn't known to be a dfs
entry when the dentry was instantiated, such as when created via
->readdir(), the DCACHE_NEED_AUTOMOUNT flag needs to be set on the
dentry in ->d_revalidate().

The false return from cifs_d_revalidate(), due to the inode now
being marked with the S_AUTOMOUNT flag, might not invalidate the
dentry if there is a concurrent unlazy path walk. This is because
the dentry reference count will be at least 2 in this case causing
d_invalidate() to return EBUSY. So the asumption that the dentry
will be discarded then correctly instantiated via ->lookup() might
not hold.
Signed-off-by: NIan Kent <raven@themaw.net>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Cc: Steve French <smfrench@gmail.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: NSteve French <sfrench@us.ibm.com>

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)>

The cifs code will attempt to open files on lookup under certain
circumstances. What happens though if we find that the file we opened
was actually a FIFO or other special file?

Currently, the open filehandle just ends up being leaked leading to
a dentry refcount mismatch and oops on umount. Fix this by having the
code close the filehandle on the server if it turns out not to be a
regular file. While we're at it, change this spaghetti if statement
into a switch too.

Cc: stable@vger.kernel.org
Reported-by: NCAI Qian <caiqian@redhat.com>
Tested-by: NCAI Qian <caiqian@redhat.com>
Reviewed-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Currently, it's always set to 0 (no oplock requested).

Cc: <stable@vger.kernel.org>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Automounting directories are now invalidated by .d_revalidate()
so to be d_instantiate()d again with the right DCACHE_NEED_AUTOMOUNT
flag
Reviewed-by: NJeff Layton <jlayton@samba.org>
Signed-off-by: NGerlando Falauto <gerlando.falauto@keymile.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

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: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>

Thus spake Jeff Layton:

"Making that a module parm would allow you to set that parameter at boot
time without needing to add special startup scripts. IMO, all of the
procfile "switches" under /proc/fs/cifs should be module parms
instead."

This patch doesn't alter the default behavior (Oplocks are enabled by
default).

To disable oplocks when loading the module, use

   modprobe cifs enable_oplocks=0

(any of '0' or 'n' or 'N' conventions can be used).

To disable oplocks at runtime using the new interface, use

   echo 0 > /sys/module/cifs/parameters/enable_oplocks

The older /proc/fs/cifs/OplockEnabled interface will be deprecated
after two releases. A subsequent patch will add an warning message
about this deprecation.

Changes since v2:
   - make enable_oplocks a 'bool'

Changes since v1:
   - eliminate the use of extra variable by renaming the old one to
     enable_oplocks and make it an 'int' type.
Reported-by: NAlexander Swen <alex@swen.nu>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSuresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: NSteve French <smfrench@gmail.com>

Running the cthon tests on a recent kernel caused this message to pop
occasionally:

    CIFS VFS: did not end path lookup where expected namelen is 0

Some added debugging showed that namelen and dfsplen were both 0 when
this occurred. That means that the read_seqretry returned true.

Assuming that the comment inside the if statement is true, this should
be harmless and just means that we raced with a rename. If that is the
case, then there's no need for alarm and we can demote this to cFYI.

While we're at it, print the dfsplen too so that we can see what
happened here if the message pops during debugging.

Cc: stable@kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

commit fec11dd9 caused
a regression when we have already mounted //server/share/a
and want to mount //server/share/a/b.

The problem is that lookup_one_len calls __lookup_hash
with nd pointer as NULL. Then __lookup_hash calls
do_revalidate in the case when dentry exists and we end
up with NULL pointer deference in cifs_d_revalidate:

if (nd->flags & LOOKUP_RCU)
	return -ECHILD;

Fix this by checking nd for NULL.
Signed-off-by: NPavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: NShirish Pargaonkar <shirishp@us.ibm.com>
CC: Stable <stable@kernel.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Reviewed-by: NShirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

commit fec11dd9 caused
a regression when we have already mounted //server/share/a
and want to mount //server/share/a/b.

The problem is that lookup_one_len calls __lookup_hash
with nd pointer as NULL. Then __lookup_hash calls
do_revalidate in the case when dentry exists and we end
up with NULL pointer deference in cifs_d_revalidate:

if (nd->flags & LOOKUP_RCU)
	return -ECHILD;

Fix this by checking nd for NULL.
Signed-off-by: NPavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... it will be set in nd->flag for all cases with non-NULL nd
(i.e. when called from do_last()).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

deal with d_move() races properly; rename_lock read-retry loop,
rcu_read_lock() held while walking to root, d_lock held over
subtraction from namelen and copying the component to stabilize
->d_name.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

secMode to sec_mode
and
cifsTconInfo to cifs_tcon
and
cifsSesInfo to cifs_ses
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Now we point superblock to a server share root and set a root dentry
appropriately. This let us share superblock between mounts like
//server/sharename/foo/bar and //server/sharename/foo further.
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

We need it to make them work with mandatory locking style because
we can fail in a situation like when kernel need to flush dirty pages
and there is a lock held by a process who opened file.
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Make CIFS use the new d_automount() dentry operation rather than abusing
follow_link() on directories.

[NOTE: THIS IS UNTESTED!]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We call CIFSSMBUnixSetPathInfo in these functions, but we have a
filehandle since an open was just done. Switch these functions to
use CIFSSMBUnixSetFileInfo instead.

In practice, these codepaths are only used if posix opens are broken.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NSteve French <sfrench@us.ibm.com>

Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Change d_hash so it may be called from lock-free RCU lookups. See similar
patch for d_compare for details.

For in-tree filesystems, this is just a mechanical change.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.

For in-tree filesystems, this is just a mechanical change.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Use vfat's method for dealing with negative dentries to preserve case,
rather than overwrite dentry name in d_revalidate, which is a bit ugly
and also gets in the way of doing lock-free path walking.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Instead, use fatfs's method for dealing with negative dentries to
preserve case, rather than overwrite dentry name in d_revalidate, which
is a bit ugly and also gets in the way of doing lock-free path walking.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

It's currently in dir.c which makes little sense...
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

All the remaining users of cifsFileInfo->pfile just use it to get
at the f_flags/f_mode. Now that we store that separately in the
cifsFileInfo, there's no need to consult the pfile at all from
a cifsFileInfo pointer.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Add a f_flags field that holds the f_flags field from the filp. We'll
need this info in case the filp ever goes away before the cifsFileInfo
does. Have cifs_reopen_file use that value instead of filp->f_flags
too and have it take a cifsFileInfo arg instead of a filp.

While we're at it, get rid of some bogus cargo-cult NULL pointer
checks in that function and reduce the level of indentation.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSuresh Jayaraman <sjayaraman@suse.de>
Acked-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>