Commit graph

254,637 commits

Author SHA1 Message Date
Russell King - ARM Linux
c7da9a56d6 ARM: PL08x: move AHB master port selection into prep_* functions
As we initialize the default cctl value in the prep_* functions along
with the increment settings, we don't need to repeat the selection of
the AHB ports each time we create a LLI entry.  Do this in the prep_*
functions once per transfer.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:13 -08:00
Russell King - ARM Linux
1cae78f120 ARM: PL08x: move cctl increment and protection setup to prep_slave_sg
We don't need to initialize the cctl increment and protection values
in the runtime_config method - we have all the inforamtion to setup
these values in prep_slave_sg().  Move their initialization there.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:13 -08:00
Russell King - ARM Linux
70b5ed6b6d ARM: PL08x: move default cctl into txd structure
Rather than modifying platform data while preparing a transfer, copy
the cctl value into the txd structure and modify the value there.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
09b3c32333 ARM: PL08x: assign ccfg DMA request signal in prep_phy_channel()
There is no need to wait until we start processing a tx descriptor
before setting up the DMA request selection in the ccfg register.
We know which channel and request will be used in prep_phy_channel(),
so setup the ccfg request selection at txd creation time in
prep_phy_channel().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
4983a04fd2 ARM: PL08x: move ccfg into txd structure
The ccfg register is used to configure the channel parameters - the type
and direction of transfer, the flow control signal and IRQ mask enables.
The type and direction of transfer is known in the relevent prep_*
function where a txd is created.  The IRQ mask enables are always set,
and the flow control signals are always set when we start processing a
txd according to phychan->signal.

If we store the ccfg value in the txd structure, we can avoid modifying
platform data - and even having it in platform data at all.

So, remove it from platform data too.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
19524d77ec ARM: PL08x: avoid duplicating registers in txd and phychan structures
As we now have all the code accessing the phychan {csrc,cdst,clli,cctl,
ccfg} members in one function, there's no point storing the data into
the struct.  Get rid of the struct members.  Re-order the register dump
in the dev_dbg() to reflect the order we write the registers to the DMA
device.

The txd {csrc,cdst,clli,cctl} values are duplicates of the lli[0]
values, so there's no point duplicating these either.  Program the DMAC
registers directly from the lli[0] values.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
c885bee4f1 ARM: PL08x: combine functions to start DMA into one function
There is no need for pl08x_config_phychan_for_txd(), pl08x_set_cregs()
and pl08x_enable_phy_chan() to be separate - they are always called in
sequence.  Combine them into one function.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
db9f136a60 ARM: PL08x: clean up LLI lookup
As the LLI list is an array, we can use maths to locate which LLI
index we're currently at, and then sum up the remaining LLI entries
until we reach the end of the list.

This makes the code much easier to read, and much less susceptible
to falling off the end of the array.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
bfddfb4505 ARM: PL08x: rename lli.next to lli.lli
The LLI pointer in the documentation is placed into the LLI register,
so name it LLI rather than 'next'.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
e25761d72c ARM: PL08x: use 'u32' for LLI structure members, not dma_addr_t
Use 'u32' for the LLI structure members, which are defined by hardware
to be 32-bit.  dma_addr_t is much more vague about its actual size.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
cace658572 ARM: PL08x: use 'size_t' for lengths
Use size_t for variables denoting lengths throughout, and use the 'z'
qualifier for printing the value.  For safety, add a BUG_ON() in
pl08x_fill_lli_for_desc() to catch the remainder potentially becoming
negative.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
56b618820c ARM: PL08x: don't try to use llis_bus as a pointer
llis_bus is the DMA address of the LLI array.  Casting it to be a
pointer just to be able to use pointer arithmetic on it is not nice.
We can trivially deal with the places where we do arithmetic on it,
and it's actually cleaner this way.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:12 -08:00
Russell King - ARM Linux
4c0df6a3ce ARM: PL08x: don't assume that the LLI pointer has the bus bit clear
We only want use the address of the LLI pointer when locating the
corresponding structure in memory, so clear the master bus selection
bit.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
19386b3234 ARM: PL08x: ensure loops use cpu_relax()
Tight loops should use cpu_relax() to allow CPUs to reduce power
consumption while waiting for events.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
8c8cc2b104 ARM: PL08x: consolidate physical channel release code
Consolidate duplicated channel release code into release_phy_channel()

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
ac3cd20df9 ARM: PL08x: consolidate common txd initialization
Consolidate code which allocates and initializes txds.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
7cb72ad959 ARM: PL08x: avoid 'void *' struct fields when we can type them properly
Avoid using 'void *' struct fields when the structs are not defined
in linux/amba/pl08x.h - instead, forward declare the struct names, and
use these instead.  This ensures we have proper typechecking.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
f96ca9ec27 ARM: PL08x: constify vendor data pointers
We should never modify the vendor data structure so make it const.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
b58b6b5bed ARM: PL08x: remove circular buffer support
The driver already won't initialize a channel with a circular buffer;
the check in pl08x_prep_channel_resources() sees to that.  Remove
circular buffer support for the time being.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
ad0a3ad33c ARM: PL08x: remove unnecessary NULL and BUG checks
The tasklet always is initialized with a non-NULL data argument.  It
is not possible for it to be called with a NULL data argument (unless
something is very wrong in the tasklet code - in which case lots of
stuff will break).  Therefore, as plchan can never be NULL, remove
this unnecessary BUG check.

In pl08x_tasklet(), we've already dereferenced plchan->at, so it can't
be NULL here.  Remove this unnecessary BUG check.

pl08x_fill_llis_for_desc() and pl08x_free_txd() are always called with
a non-NULL txd argument - either as a consequence of the code paths or
as a result of other checks already in place.  We don't need to repeat
the non-NULL check in these functions.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
730404ac1c ARM: PL08x: remove unnecessary includes
We don't need to include linux/pci.h as we aren't a PCI driver.  We
aren't doing any processor specific functions, so asm/processor.h is
not required.  asm/cacheflush.h shouldn't be used, we have the DMA API
for this.  DMA interfaces aren't required as we're only implementing
the dmaengine API and not a platform-private DMA API.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
9c13299268 ARM: PL08x: prefix hex numbers with 0x
A driver which emits both decimal and hex numbers in its printk
creates confusion as to what is what.  Prefix hex numbers with 0x.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
b05cd8f4c0 ARM: PL08x: improve the announcement printk
Include the revision number of the PL08x primecell in the boot-time
printk to allow proper identification of the peripheral.  Reformat
the announcement printk format reflect what we do for other primecell
drivers - generally "PLXXX revX at 0xNNNNNNNN irq X".

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:11 -08:00
Russell King - ARM Linux
9dc2c200a0 ARM: PL08x: add comment explaining the flow control methods
Explain the two flow control methods which the PL08x implements, along
with the problem which peripheral flow control presents.  This helps
people understand why we are unable to use these DMA controllers with
(eg) the MMCI.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
3e2a037c1d ARM: PL08x: fix sparse warnings
drivers/dma/amba-pl08x.c:1895:40: warning: Unknown escape '%'
drivers/dma/amba-pl08x.c:1903:40: warning: Unknown escape '%'
drivers/dma/amba-pl08x.c:513:6: warning: symbol 'pl08x_choose_master_bus' was not declared. Should it be static?
drivers/dma/amba-pl08x.c:604:5: warning: symbol 'pl08x_fill_llis_for_desc' was not declared. Should it be static?
drivers/dma/amba-pl08x.c:1442:32: warning: symbol 'pl08x_prep_slave_sg' was not declared. Should it be static?

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
98838f90d9 ARM: PL08x: fix deadlock in terminate_all
Trying to disable a tasklet while holding a spinlock which the tasklet
will take is a recipe for deadlock - tasklet_disable() will wait for the
tasklet to finish running, which it will never do.  In any case, there
is not a corresponding tasklet_enable(), so once the tasklet is disabled,
it will never run again until reboot.

It's safe to just remove the tasklet_disable() as we remove all current
and pending descriptors before releasing this spinlock.  This means that
the tasklet will find no remaining work if it subsequently runs.

The only remaining issue is that the callback for an already submitted
txd may be in progress, or even called after terminate_all() returns.
There's not much that can be done about that as waiting for the callback
to complete before returning will also lead to deadlocks.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
9c0bb43bbd ARM: PL08x: fix missed spin-unlock in pl08x_issue_pending()
pl08x_issue_pending() returns with the spinlock locked and interrupts
disabled if the channel is waiting for a physical DMA to become free.
This is wrong - especially as pl08x_issue_pending() is an API function
as it leads to deadlocks.  Fix it to always return with the spinlock
unlocked.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
dafa73171b ARM: PL08x: fix a leak when preparing TXDs
If we fail to allocate the LLI, the prep_* function will return NULL.
However, the TXD we allocated will not be placed on any list, nor
will it be freed - we'll just drop all references to it.  Make sure
we free it rather than leaking TXDs.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
bf072af461 ARM: PL08x: fix locking in tasklet
Tasklets are run from an interruptible context.  The slave DMA functions
can be called from within IRQ handlers.  Taking the spinlock without
disabling interrupts allows an interrupt handler to run, which may try
to take the spinlock again, resulting in deadlock.  Fix this by using
the irqsave spinlocks.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
91aa5fadb8 ARM: PL08x: fix atomic_t usage and tx_submit() return value range
The last_issued variable uses an atomic type, which is only
incremented inside a protected region, and then read.  Everywhere else
only reads the value, so it isn't using atomic_t correctly, and it
doesn't even need to.  Moreover, the DMA engine code provides us with
a variable for this already - chan.cookie.  Use chan.cookie instead.

Also, avoid negative dma_cookie_t values - negative returns from
tx_submit() mean failure, yet in reality we always succeed.  Restart
from cookie 1, just like other DMA engine drivers do.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
4440aacf3a ARM: PL08x: fix array overflow in dma_set_runtime_config()
If maxburst was passed in as zero, we would overflow the burst_sizes[]
array.  Fix this by checking for this condition, and defaulting to
single transfer 'bursts'.

Improve the readability of the loop using a for() loop rather than
a while() loop with the iterator initialized far from the loop.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:16:10 -08:00
Russell King - ARM Linux
e8b5e11df3 ARM: PL08x: fix spelling errors
Correct mis-spellings in comments and printk strings.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 19:13:38 -08:00
Per Forlin
d49278e335 dmaengine: dma40: Add support to split up large elements
The maximum transfer size of the stedma40 is (64k-1) x data-width.
If the transfer size of one element exceeds this limit
the job is split up and sent as linked transfer.

Signed-off-by: Per Forlin <per.forlin@linaro.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-01-04 17:20:43 -08:00
Linus Torvalds
3c0eee3fe6 Linux 2.6.37 v2.6.37 2011-01-04 16:50:19 -08:00
Takuma Umeya
6f3d772fb8 nfs4: set source address when callback is generated
when callback is generated in NFSv4 server, it doesn't set the source
address. When an alias IP is utilized on NFSv4 server and suppose the
client is accessing via that alias IP (e.g. eth0:0), the client invokes
the callback to the IP address that is set on the original device (e.g.
eth0). This behavior results in timeout of xprt.
The patch sets the IP address that the client should invoke callback to.

Signed-off-by: Takuma Umeya <tumeya@redhat.com>
[bfields@redhat.com: Simplify gen_callback arguments, use helper function]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 19:43:01 -05:00
Kukjin Kim
ab10f1dd91 Merge branch 'dev/cleanup-clocks' into for-next 2011-01-05 09:39:23 +09:00
Tejun Heo
140e3008e7 [SCSI] sd,sr: kill compat SDEV_MEDIA_CHANGE event
SDEV_MEDIA_CHANGE event was first added by commit a341cd0f (SCSI: add
asynchronous event notification API) for SATA AN support and then
extended to cover generic media change events by commit 285e9670
([SCSI] sr,sd: send media state change modification events).

This event was mapped to block device in userland with all properties
stripped to simulate CHANGE event on the block device, which, in turn,
was used to trigger further userspace action on media change.

The recent addition of disk event framework kept this event for
backward compatibility but it turns out to be unnecessary and causes
erratic and inefficient behavior.  The new disk event generates proper
events on the block devices and the compat events are mapped to block
device with all properties stripped, so the block device ends up
generating multiple duplicate events for single actual event.

This patch removes the compat event generation from both sr and sd as
suggested by Kay Sievers.  Both existing and newer versions of udev
and the associated tools will behave better with the removal of these
events as they from the beginning were expecting events on the block
devices.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-04 17:53:50 -06:00
J. Bruce Fields
3c72602340 nfsd4: return nfs errno from name_to_id functions
This avoids the need for the confusing ESRCH mapping.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 18:22:11 -05:00
J. Bruce Fields
775a1905e1 nfsd4: remove outdated pathname-comments
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 18:22:10 -05:00
J. Bruce Fields
2ca72e17e5 nfsd4: move idmap and acl header files into fs/nfsd
These are internal nfsd interfaces.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 18:22:09 -05:00
J. Bruce Fields
f6af99ec1b nfsd4: name->id mapping should fail with BADOWNER not BADNAME
According to rfc 3530 BADNAME is for strings that represent paths;
BADOWNER is for user/group names that don't map.

And the too-long name should probably be BADOWNER as well; it's
effectively the same as if we couldn't map it.

Cc: stable@kernel.org
Reported-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reported-by: Simon Kirby <sim@hostway.ca>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 18:21:36 -05:00
Alex Deucher
17db7042b7 drm/radeon/kms: implement gpu lockup check for evergreen
Now that soft reset works, we can add this.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-01-05 08:31:50 +10:00
Dave Airlie
4f125010d2 Merge branch 'master' of /home/airlied/kernel/linux-2.6 into drm-core-next 2011-01-05 08:31:08 +10:00
Linus Torvalds
65f42886e2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  ipv4/route.c: respect prefsrc for local routes
  bridge: stp: ensure mac header is set
  bridge: fix br_multicast_ipv6_rcv for paged skbs
  atl1: fix oops when changing tx/rx ring params
  drivers/atm/atmtcp.c: add missing atm_dev_put
  starfire: Fix dma_addr_t size test for MIPS
  tg3: fix return value check in tg3_read_vpd()
  Broadcom CNIC core network driver: fix mem leak on allocation failures in cnic_alloc_uio_rings()
  ISDN, Gigaset: Fix memory leak in do_disconnect_req()
  CAN: Use inode instead of kernel address for /proc file
  skfp: testing the wrong variable in skfp_driver_init()
  ppp: allow disabling multilink protocol ID compression
  ehea: Avoid changing vlan flags
  ueagle-atm: fix PHY signal initialization race
2011-01-04 13:55:49 -08:00
J. Bruce Fields
255c7cf810 locks: minor setlease cleanup
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:29 -05:00
J. Bruce Fields
c45821d263 locks: eliminate fl_mylease callback
The nfs server only supports read delegations for now, so we don't care
how conflicts are determined.  All we care is that unlocks are
recognized as matching the leases they are meant to remove.  After the
last patch, a comparison of struct files will work for that purpose.  So
we no longer need this callback.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:28 -05:00
J. Bruce Fields
c84d500bc4 nfsd4: use a single struct file for delegations
When we converted to sharing struct filess between nfs4 opens I went too
far and also used the same mechanism for delegations.  But keeping
a reference to the struct file ensures it will outlast the lease, and
allows us to remove the lease with the same file as we added it.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:27 -05:00
J. Bruce Fields
e63eb93750 nfsd4: eliminate lease delete callback
nfsd controls the lifetime of the lease, not the lock code, so there's
no need for this callback on lease destruction.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:26 -05:00
J. Bruce Fields
fdef7aa5d4 svcrpc: ensure cache_check caller sees updated entry
Supposes cache_check runs simultaneously with an update on a different
CPU:

	cache_check			task doing update
	^^^^^^^^^^^			^^^^^^^^^^^^^^^^^

	1. test for CACHE_VALID		1'. set entry->data
	   & !CACHE_NEGATIVE

	2. use entry->data		2'. set CACHE_VALID

If the two memory writes performed in step 1' and 2' appear misordered
with respect to the reads in step 1 and 2, then the caller could get
stale data at step 2 even though it saw CACHE_VALID set on the cache
entry.

Add memory barriers to prevent this.

Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:25 -05:00
J. Bruce Fields
6bab93f87e svcrpc: take lock on turning entry NEGATIVE in cache_check
We attempt to turn a cache entry negative in place.  But that entry may
already have been filled in by some other task since we last checked
whether it was valid, so we could be modifying an already-valid entry.
If nothing else there's a likely leak in such a case when the entry is
eventually put() and contents are not freed because it has
CACHE_NEGATIVE set.

So, take the cache_lock just as sunrpc_cache_update() does.

Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-01-04 16:49:24 -05:00