We "goto finish" from several places where "exp" is an ERR_PTR. Also I
changed the check for "fsid_key" so that it was consistent with the check
I added.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Both the _lookup and the _update functions for these two caches
independently calculate the hash of the key.
So factor out that code for improved reuse.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Commit f39bde24b2 fixed the error return from PUTROOTFH in the
case where there is no pseudofilesystem.
This is really a case we shouldn't hit on a correctly configured server:
in the absence of a root filehandle, there's no point accepting version
4 NFS rpc calls at all.
But the shared responsibility between kernel and userspace here means
the kernel on its own can't eliminate the possiblity of this happening.
And we have indeed gotten this wrong in distro's, so new client-side
mount code that attempts to negotiate v4 by default first has to work
around this case.
Therefore when commit f39bde24b2 arrived at roughly the same
time as the new v4-default mount code, which explicitly checked only for
the previous error, the result was previously fine mounts suddenly
failing.
We'll fix both sides for now: revert the error change, and make the
client-side mount workaround more robust.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The new .h files have paths at the top that are now out of date. While
we're here, just remove all of those from fs/nfsd; they never served any
purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We want to allow exports of symlinks, to allow mountd to communicate to
the kernel which symlinks lead to exports, and hence which symlinks need
to be visible on the pseudofilesystem.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
NFSv4 differs from v2 and v3 in that it presents a single unified
filesystem tree, whereas v2 and v3 exported multiple filesystem (whose
roots could be found using a separate mount protocol).
Our original NFSv4 server implementation asked the administrator to
designate a single filesystem as the NFSv4 root, then to mount
filesystems they wished to export underneath. (Often using bind mounts
of already-existing filesystems.)
This was conceptually simple, and allowed easy implementation, but
created a serious obstacle to upgrading between v2/v3: since the paths
to v4 filesystems were different, administrators would have to adjust
all the paths in client-side mount commands when switching to v4.
Various workarounds are possible. For example, the administrator could
export "/" and designate it as the v4 root. However, the security risks
of that approach are obvious, and in any case we shouldn't be requiring
the administrator to take extra steps to fix this problem; instead, the
server should present consistent paths across different versions by
default.
These patches take a modified version of that approach: we provide a new
export option which exports only a subset of a filesystem. With this
flag, it becomes safe for mountd to export "/" by default, with no need
for additional configuration.
We begin just by defining the new flag.
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Lots of include/linux/nfsd/* headers are only used by
nfsd module. Move them to the source directory
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that the headers are fixed and carry their own wait, all fs/nfsd/
source files can include a minimal set of headers. and still compile just
fine.
This patch should improve the compilation speed of the nfsd module.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We really shouldn't hit this case at all, and forthcoming kernel and
nfs-utils changes should eliminate this case; if it does happen,
consider it a bug rather than reporting an error that doesn't really
make sense for the operation (since there's no reason for a server to be
accepting v4 traffic yet have no root filehandle).
Also move some exp_pseudoroot code into a helper function while we're
here.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Make all seq_operations structs const, to help mitigate against
revectoring user-triggerable function pointers.
This is derived from the grsecurity patch, although generated from scratch
because it's simpler than extracting the changes from there.
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
nfsd4_path() allocates a temporary filehandle and then fails to free it
before the function exits, leaking reference counts to the dentry and
export that it refers to.
Also, nfsd4_lookupp() puts the result of exp_pseudoroot() in a temporary
filehandle which it releases on success of exp_pseudoroot() but not on
failure; fix exp_pseudoroot to ensure that on failure it releases the
filehandle before returning.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
For events that are rare, such as referral DNS lookups, it makes limited
sense to have a daemon constantly listening for upcalls on a channel. An
alternative in those cases might simply be to run the app that fills the
cache using call_usermodehelper_exec() and friends.
The following patch allows the cache_detail to specify alternative upcall
mechanisms for these particular cases.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We might as well do all of these at the end. Fix up a couple minor
style nits while we're there.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Drop reference to export key on error. Compile tested.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Once clp is assigned, it never becomes NULL, so we can make a label for it
in the error handling code. Because the call to path_lookup follows the
call to auth_domain_find, its error handling code should jump to this new
label.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@r@
expression x,E;
statement S;
position p1,p2,p3;
@@
(
if ((x = auth_domain_find@p1(...)) == NULL || ...) S
|
x = auth_domain_find@p1(...)
... when != x
if (x == NULL || ...) S
)
<...
if@p3 (...) { ... when != auth_domain_put(x)
when != if (x) { ... auth_domain_put(x); ...}
return@p2 ...;
}
...>
(
return x;
|
return 0;
|
x = E
|
E = x
|
auth_domain_put(x)
)
@exists@
position r.p1,r.p2,r.p3;
expression x;
int ret != 0;
statement S;
@@
* x = auth_domain_find@p1(...)
<...
* if@p3 (...)
S
...>
* return@p2 \(NULL\|ret\);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This adds IPv6 support to the interfaces that are used to express nfsd
exports. All addressed are stored internally as IPv6; backwards
compatibility is maintained using mapped addresses.
Thanks to Bruce Fields, Brian Haley, Neil Brown and Hideaki Joshifuji
for comments
Signed-off-by: Aurelien Charbon <aurelien.charbon@bull.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Brian Haley <brian.haley@hp.com>
Cc: YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
d_path() is used on a <dentry,vfsmount> pair. Lets use a struct path to
reflect this.
[akpm@linux-foundation.org: fix build in mm/memory.c]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Bryan Wu <bryan.wu@analog.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
seq_path() is always called with a dentry and a vfsmount from a struct path.
Make seq_path() take it directly as an argument.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I'm embedding struct path into struct svc_expkey.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add path_put() functions for releasing a reference to the dentry and
vfsmount of a struct path in the right order
* Switch from path_release(nd) to path_put(&nd->path)
* Rename dput_path() to path_put_conditional()
[akpm@linux-foundation.org: fix cifs]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: <linux-fsdevel@vger.kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven French <sfrench@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Neither EPERM and ENOENT map to valid errors for PUTROOTFH according to
rfc 3530, and, if anything, ENOENT is likely to be slightly more
informative; so don't bother mapping ENOENT to EPERM. (Probably this
was originally done because one likely cause was that there is an fsid=0
export but that it isn't permitted to this particular client. Now that
we allow WRONGSEC returns, this is somewhat less likely.)
In the long term we should work to make this situation less likely,
perhaps by turning off nfsv4 service entirely in the absence of the
pseudofs root, or constructing a pseudofilesystem root ourselves in the
kernel as necessary.
Thanks to Benny Halevy <bhalevy@panasas.com> for pointing out this
problem.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Benny Halevy <bhalevy@panasas.com>
Newer server features such as nfsv4 and gss depend on proc to work, so a
failure to initialize the proc files they need should be treated as
fatal.
Thanks to Andrew Morton for style fix and compile fix in case where
CONFIG_NFSD_V4 is undefined.
Cc: Andrew Morton <akpm@linux-foundation.org>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's really nothing much the caller can do if cache unregistration
fails. And indeed, all any caller does in this case is print an error
and continue. So just return void and move the printk's inside
cache_unregister.
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that all filesystems are converted remove support for the old methods.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch makes the following needlessly global functions static:
- exp_get_by_name()
- exp_parent()
- exp_find()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A succesful downcall with a negative result (which indicates that the given
filesystem is not exported to the given user) should not return an error.
Currently mountd is depending on stdio to write these downcalls. With some
versions of libc this appears to cause subsequent writes to attempt to write
all accumulated data (for which writes previously failed) along with any new
data. This can prevent the kernel from seeing responses to later downcalls.
Symptoms will be that nfsd fails to respond to certain requests.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For display purposes, treat uid's and gid's as unsigned ints for now.
Also fix a typo.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I converted the various export-returning functions to return -ENOENT instead
of NULL, but missed a few cases.
This particular case could cause actual bugs in the case of a krb5 client that
doesn't match any ip-based client and that is trying to access a filesystem
not exported to krb5 clients.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add secinfo information to the display in proc/net/sunrpc/nfsd.export/content.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Factor out some code to be shared by secinfo display code. Remove some
unnecessary conditional printing of commas where we know the condition is
true.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the first actual use of the secinfo information by using it to return
nfserr_wrongsec when an export is found that doesn't allow the flavor used on
this request.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With this patch, we fall back on using the gss/pseudoflavor only if we fail to
find a matching auth_unix export that has a secinfo list.
As long as sec= options aren't used, there's still no change in behavior here
(except possibly for some additional auth_unix cache lookups, whose results
will be ignored).
The sec= option, however, is not actually enforced yet; later patches will add
the necessary checks.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We want it to be possible for users to restrict exports both by IP address and
by pseudoflavor. The pseudoflavor information has previously been passed
using special auth_domains stored in the rq_client field. After the preceding
patch that stored the pseudoflavor in rq_pflavor, that's now superfluous; so
now we use rq_client for the ip information, as auth_null and auth_unix do.
However, we keep around the special auth_domain in the rq_gssclient field for
backwards compatibility purposes, so we can still do upcalls using the old
"gss/pseudoflavor" auth_domain if upcalls using the unix domain to give us an
appropriate export. This allows us to continue supporting old mountd.
In fact, for this first patch, we always use the "gss/pseudoflavor"
auth_domain (and only it) if it is available; thus rq_client is ignored in the
auth_gss case, and this patch on its own makes no change in behavior; that
will be left to later patches.
Note on idmap: I'm almost tempted to just replace the auth_domain in the idmap
upcall by a dummy value--no version of idmapd has ever used it, and it's
unlikely anyone really wants to perform idmapping differently depending on the
where the client is (they may want to perform *credential* mapping
differently, but that's a different matter--the idmapper just handles id's
used in getattr and setattr). But I'm updating the idmapd code anyway, just
out of general backwards-compatibility paranoia.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Split the callers of exp_get_by_name(), exp_find(), and exp_parent() into
those that are processing requests and those that are doing other stuff (like
looking up filehandles for mountd).
No change in behavior, just a (fairly pointless, on its own) cleanup.
(Note this has the effect of making nfsd_cross_mnt() pass rqstp->rq_client
instead of exp->ex_client into exp_find_by_name(). However, the two should
have the same value at this point.)
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We're passing three arguments to exp_pseudoroot, two of which are just fields
of the svc_rqst. Soon we'll want to pass in a third field as well. So let's
just give up and pass in the whole struct svc_rqst.
Also sneak in some minor style cleanups while we're at it.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We add a list of pseudoflavors to each export downcall, which will be used
both as a list of security flavors allowed on that export, and (in the order
given) as the list of pseudoflavors to return on secinfo calls.
This patch parses the new downcall information and adds it to the export
structure, but doesn't use it for anything yet.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently exp_find(), exp_get_by_name(), and friends, return an export on
success, and on failure return:
errors -EAGAIN (drop this request pending an upcall) or
-ETIMEDOUT (an upcall has timed out), or
return NULL, which can mean either that there was a memory allocation
failure, or that an export was not found, or that a passed-in
export lacks an auth_domain.
Many callers seem to assume that NULL means that an export was not found,
which may lead to bugs in the case of a memory allocation failure.
Modify these functions to distinguish between the two NULL cases by returning
either -ENOENT or -ENOMEM. They now never return NULL. We get to simplify
some code in the process.
We return -ENOENT in the case of a missing auth_domain. This case should
probably be removed (or converted to a bug) after confirming that it can never
happen.
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Carpenter