Now that we're allowing more DRC entries, it becomes a lot easier to hit
problems with XID collisions. In order to mitigate those, calculate a
checksum of up to the first 256 bytes of each request coming in and store
that in the cache entry, along with the total length of the request.

This initially used crc32, but Chuck Lever and Jim Rees pointed out that
crc32 is probably more heavyweight than we really need for generating
these checksums, and recommended looking at using the same routines that
are used to generate checksums for IP packets.

On an x86_64 KVM guest measurements with ftrace showed ~800ns to use
csum_partial vs ~1750ns for crc32.  The difference probably isn't
terribly significant, but for now we may as well use csum_partial.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Stones-thrown-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

When GSSAPI integrity signatures are in use, or when we're using GSSAPI
privacy with the v2 token format, there is a trailing checksum on the
xdr_buf that is returned.

It's checked during the authentication stage, and afterward nothing
cares about it. Ordinarily, it's not a problem since the XDR code
generally ignores it, but it will be when we try to compute a checksum
over the buffer to help prevent XID collisions in the duplicate reply
cache.

Fix the code to trim off the checksums after verifying them. Note that
in unwrap_integ_data, we must avoid trying to reverify the checksum if
the request was deferred since it will no longer be present when it's
revisited.
Signed-off-by: Jeff Layton <jlayton@redhat.com>

...these pages aren't necessarily contiguous.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

These routines are used by server and client code, so having them in a
separate header would be best.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

When copying an address, we should also copy the scopeid in the event
that this is a link-local address and the scope matters.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

We don't really need to preallocate at all; just allocate and initialize
everything at once, but leave the sc_type field initially 0 to prevent
finding the stateid till it's fully initialized.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

When free nfs-client, it must free the ->cl_stateids.

Cc: stable@kernel.org
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Since we dynamically allocate them now, allow the system to call us up
to release them if it gets low on memory. Since these entries aren't
replaceable, only free ones that are expired or that are over the cap.
The the seeks value is set to '1' however to indicate that freeing the
these entries is low-cost.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It's not sufficient to only clean the cache when requests come in. What
if we have a flurry of activity and then the server goes idle? Add a
workqueue job that will clean the cache every RC_EXPIRE period.

Care is taken to only run this when we expect to have entries expiring.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There's no need to keep entries around that we're declaring RC_NOCACHE.
Ditto if there's a problem with the entry.

With this change too, there's no need to test for RC_UNUSED in the
search function. If the entry's in the hash table then it's either
INPROG or DONE.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

With the change to dynamically allocate entries, the cache is never
disabled on the fly. Remove this flag.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The existing code keeps a fixed-size cache of 1024 entries. This is much
too small for a busy server, and wastes memory on an idle one.  This
patch changes the code to dynamically allocate and free these cache
entries.

A cap on the number of entries is retained, but it's much larger than
the existing value and now scales with the amount of low memory in the
machine.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

...otherwise, we end up with the list ordering wrong. Currently, it's
not a problem since we skip RC_INPROG entries, but keeping the ordering
strict will be necessary for a later patch that adds a cache cleaner.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

commit 885c91f7 in Bruce's tree was causing oopses for me:

general protection fault: 0000 [#1] SMP
Modules linked in: nfsd(OF) nfs_acl(OF) auth_rpcgss(OF) lockd(OF) sunrpc(OF) kvm_amd kvm microcode i2c_piix4 virtio_net virtio_balloon cirrus drm_kms_helper ttm drm virtio_blk i2c_core
CPU 0
Pid: 564, comm: exportfs Tainted: GF          O 3.8.0-0.rc5.git2.1.fc19.x86_64 #1 Bochs Bochs
RIP: 0010:[<ffffffff811b1509>]  [<ffffffff811b1509>] kfree+0x49/0x280
RSP: 0018:ffff88007a3d7c50  EFLAGS: 00010203
RAX: 01adaf8dadadad80 RBX: 6b6b6b6b6b6b6b6b RCX: 0000000000000001
RDX: ffffffff7fffffff RSI: 0000000000000000 RDI: 6b6b6b6b6b6b6b6b
RBP: ffff88007a3d7c80 R08: 6b6b6b6b6b6b6b6b R09: 0000000000000000
R10: 0000000000000018 R11: 0000000000000000 R12: ffff88006a117b50
R13: ffffffffa01a589c R14: ffff8800631b0f50 R15: 01ad998dadadad80
FS:  00007fcaa3616740(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f5d84b6fdd8 CR3: 0000000064db4000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process exportfs (pid: 564, threadinfo ffff88007a3d6000, task ffff88006af28000)
Stack:
 ffff88007a3d7c80 ffff88006a117b68 ffff88006a117b50 0000000000000000
 ffff8800631b0f50 ffff88006a117b50 ffff88007a3d7ca0 ffffffffa01a589c
 ffff880036be1148 ffff88007a3d7cf8 ffff88007a3d7e28 ffffffffa01a6a98
Call Trace:
 [<ffffffffa01a589c>] svc_export_put+0x5c/0x70 [nfsd]
 [<ffffffffa01a6a98>] svc_export_parse+0x328/0x7e0 [nfsd]
 [<ffffffffa016f1c7>] cache_do_downcall+0x57/0x70 [sunrpc]
 [<ffffffffa016f25e>] cache_downcall+0x7e/0x100 [sunrpc]
 [<ffffffffa016f338>] cache_write_procfs+0x58/0x90 [sunrpc]
 [<ffffffffa016f2e0>] ? cache_downcall+0x100/0x100 [sunrpc]
 [<ffffffff8123b0e5>] proc_reg_write+0x75/0xb0
 [<ffffffff811ccecf>] vfs_write+0x9f/0x170
 [<ffffffff811cd089>] sys_write+0x49/0xa0
 [<ffffffff816e0919>] system_call_fastpath+0x16/0x1b
Code: 66 66 66 90 48 83 fb 10 0f 86 c3 00 00 00 48 89 df 49 bf 00 00 00 00 00 ea ff ff e8 f2 12 ea ff 48 c1 e8 0c 48 c1 e0 06 49 01 c7 <49> 8b 07 f6 c4 80 0f 85 1d 02 00 00 49 8b 07 a8 80 0f 84 ee 01
RIP  [<ffffffff811b1509>] kfree+0x49/0x280
 RSP <ffff88007a3d7c50>

I think Majianpeng's patch is correct, but incomplete. In order for it
to be safe to free the ex_uuid unconditionally in svc_export_put, we
need to make sure it's initialized to NULL in the init routine.

Cc: majianpeng <majianpeng@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Later, we'll need more than one call site for this, so break it out
into a new function.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Add a preprocessor constant for the expiry time of cache entries, and
move the test for an expired entry into a function. Note that the current
code does not test for RC_INPROG. It just assumes that it won't take more
than 2 minutes to fill out an in-progress entry.

I'm not sure how valid that assumption is though, so let's just ensure
that we never consider an RC_INPROG entry to be expired.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Entries can only get a c_type of RC_REPLBUFF iff they are
RC_DONE. Therefore the test for RC_DONE isn't necessary here.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Currently we use kmalloc() which wastes a little bit of memory on each
allocation since it's a power of 2 allocator. Since we're allocating a
1024 of these now, and may need even more later, let's create a new
slabcache for them.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The reply cache code never returns this status.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The locking rules for cache entries say that locking the cache_lock
isn't needed if you're just touching the current entry. Earlier
in this function we set rp->c_state to RC_UNUSED without any locking,
so I believe it's ok to do the same here.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Currently, it only stores the first 16 bytes of any address. struct
sockaddr_in6 is 28 bytes however, so we're currently ignoring the last
12 bytes of the address.

Expand the c_addr field to a sockaddr_in6, and cast it to a sockaddr_in
as necessary. Also fix the comparitor to use the existing RPC
helpers for this.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In func svc_export_parse, the uuid which used kmemdup to alloc will be
changed in func export_update.So the later kfree don't free this memory.
And it can't be free in func svc_export_parse because other place still
used.So put this operation in func svc_export_put.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The current code will allow silly things like:

	echo "+2 +3 +4 +7.1">/proc/fs/nfsd/versions
Reported-by: Fan Chaoting <fanchaoting@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

If CONFIG_LOCKDEP is disabled, then there would be a warning like this:

  CC [M]  fs/nfsd/nfs4state.o
fs/nfsd/nfs4state.c: In function ‘free_client’:
fs/nfsd/nfs4state.c:1051:19: warning: unused variable ‘nn’ [-Wunused-variable]

So, let's add "maybe_unused" tag to this variable.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There is a race in enqueueing thread to a pool and
waking up a thread.
lockd doesn't wake up on reception of lock granted callback
if svc_wake_up() is called before lockd's thread is added
to a pool.
Signed-off-by: Andriy Skulysh <Andriy_Skulysh@xyratex.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The write function doesn't be implemented in file content, and it's meaningless
to write data into this file directly. Remove write permission from it.
Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In the procedure of CREATE_SESSION, the state is locked after
alloc_conn_from_crses(). If the allocation fails, the function
goes to "out_free_session", and then "out" where there is an
unlock function.
Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

In alloc_session(), numslots is the correct slot number used by the session.
But the slot number passed to nfsd4_put_drc_mem() is the one from nfs client.
Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

It seems slightly simpler to make nfsd4_encode_fattr rather than its
callers responsible for advancing the write pointer on success.

(Also: the count == 0 check in the verify case looks superfluous.
Running out of buffer space is really the only reason fattr encoding
should fail with eresource.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pull LED fix from Bryan Wu.

* 'fixes-for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds:
  leds: leds-gpio: set devm_gpio_request_one() flags param correctly

commit a99d76f9 leds: leds-gpio: use gpio_request_one

changed the leds-gpio driver to use gpio_request_one() instead
of gpio_request() + gpio_direction_output()

Unfortunately, it also made a semantic change that breaks the
leds-gpio driver.

The gpio_request_one() flags parameter was set to:

GPIOF_DIR_OUT | (led_dat->active_low ^ state)

Since GPIOF_DIR_OUT is 0, the final flags value will just be the
XOR'ed value of led_dat->active_low and state.

This value were used to distinguish between HIGH/LOW output initial
level and call gpio_direction_output() accordingly.

With this new semantic gpio_request_one() will take the flags value
of 1 as a configuration of input direction (GPIOF_DIR_IN) and will
call gpio_direction_input() instead of gpio_direction_output().

int gpio_request_one(unsigned gpio, unsigned long flags, const char *label)
{
..
	if (flags & GPIOF_DIR_IN)
		err = gpio_direction_input(gpio);
	else
		err = gpio_direction_output(gpio,
				(flags & GPIOF_INIT_HIGH) ? 1 : 0);
..
}

The right semantic is to evaluate led_dat->active_low ^ state and
set the output initial level explicitly.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reported-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

Pull watchdog fixes from Wim Van Sebroeck:
 "This fixes some small errors in the new da9055 driver, eliminates a
  compiler warning and adds DT support for the twl4030_wdt driver (so
  that we can have multiple watchdogs with DT on the omap platforms)."

* git://www.linux-watchdog.org/linux-watchdog:
  watchdog: twl4030_wdt: add DT support
  watchdog: omap_wdt: eliminate unused variable and a compiler warning
  watchdog: da9055: Don't update wdt_dev->timeout in da9055_wdt_set_timeout error path
  watchdog: da9055: Fix invalid free of devm_ allocated data

Pull PCI updates from Bjorn Helgaas:
 "Some fixes for v3.8.  They include a fix for the new SR-IOV sysfs
  management support, an expanded quirk for Ricoh SD card readers, a
  Stratus DMI quirk fix, and a PME polling fix."

* tag '3.8-pci-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: Reduce Ricoh 0xe822 SD card reader base clock frequency to 50MHz
  PCI/PM: Do not suspend port if any subordinate device needs PME polling
  PCI: Add PCIe Link Capability link speed and width names
  PCI: Work around Stratus ftServer broken PCIe hierarchy (fix DMI check)
  PCI: Remove spurious error for sriov_numvfs store and simplify flow

Commit 56c176c9 ("UAPI: strip the _UAPI prefix from header guards
during header installation") strips the _UAPI prefix from header guards,
but only if there's a single space between the cpp directive and the
label.

Make it more flexible and able to handle tabs and multiple white space
characters.
Signed-off-by: David Howells <dhowell@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Empty files can get deleted by the patch program, so remove empty Kbuild
files and their links from the parent Kbuilds.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs

Pull ecryptfs fixes from Tyler Hicks:
 "Two self-explanatory fixes and a third patch which improves
  performance: when overwriting a full page in the eCryptfs page cache,
  skip reading in and decrypting the corresponding lower page."

* tag 'ecryptfs-3.8-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tyhicks/ecryptfs:
  fs/ecryptfs/crypto.c: make ecryptfs_encode_for_filename() static
  eCryptfs: fix to use list_for_each_entry_safe() when delete items
  eCryptfs: Avoid unnecessary disk read and data decryption during writing