add_early_randomness() is called by hwrng_register() when the
hardware is added. If this hardware and its module are present
at boot, and if there is no data available the boot hangs until
data are available and can't be interrupted.

For instance, in the case of virtio-rng, in some cases the host can be
not able to provide enough entropy for all the guests.

We can have two easy ways to reproduce the problem but they rely on
misconfiguration of the hypervisor or the egd daemon:

- if virtio-rng device is configured to connect to the egd daemon of the
host but when the virtio-rng driver asks for data the daemon is not
connected,

- if virtio-rng device is configured to connect to the egd daemon of the
host but the egd daemon doesn't provide data.

The guest kernel will hang at boot until the virtio-rng driver provides
enough data.

To avoid that, call rng_get_data() in non-blocking mode (wait=0)
from add_early_randomness().
Signed-off-by: NLaurent Vivier <lvivier@redhat.com>
Fixes: d9e79726 ("hwrng: add randomness to system from rng...")
Cc: <stable@vger.kernel.org>
Reviewed-by: NTheodore Ts'o <tytso@mit.edu>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The return valude of add_comp_head() is int, but @head_size is size_t,
which is a unsigned type.

	size_t head_size;
	...
	if (head_size < 0)  // it will never work
		return -ENOMEM

Modify the type of @head_size to int, then change the type to size_t
when invoke hisi_zip_create_req() as a parameter.

Fixes: 62c455ca ("crypto: hisilicon - add HiSilicon ZIP accelerator support")
Signed-off-by: NYunfeng Ye <yeyunfeng@huawei.com>
Acked-by: NZhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

When dma_pool_zalloc() fail in sec_alloc_and_fill_hw_sgl(),
dma_pool_free() is invoked, but the parameters that sgl_current and
sgl_current->next_sgl is not match.

Using sec_free_hw_sgl() instead of the original free routine.

Fixes: 915e4e84 ("crypto: hisilicon - SEC security accelerator driver")
Signed-off-by: NYunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

There are two problems in sec_free_hw_sgl():

First, when sgl_current->next is valid, @hw_sgl will be freed in the
first loop, but it free again after the loop.

Second, sgl_current and sgl_current->next_sgl is not match when
dma_pool_free() is invoked, the third parameter should be the dma
address of sgl_current, but sgl_current->next_sgl is the dma address
of next chain, so use sgl_current->next_sgl is wrong.

Fix this by deleting the last dma_pool_free() in sec_free_hw_sgl(),
modifying the condition for while loop, and matching the address for
dma_pool_free().

Fixes: 915e4e84 ("crypto: hisilicon - SEC security accelerator driver")
Signed-off-by: NYunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch fixes an unused variable warning from the compiler when the
driver is being compiled without PCI support in the kernel.

Fixes: 625f269a ("crypto: inside-secure - add support for...")
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Add missing break statement in order to prevent the code from falling
through to case CRYPTO_ALG_TYPE_AHASH.

Fixes: aeb4c132 ("crypto: talitos - Convert to new AEAD interface")
Cc: stable@vger.kernel.org
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

While storing an int in a pointer is safe the compiler is not
happy about it.  So we need some extra casting in order to make
this warning free.

Fixes: 1d3f75bce123 ("crypto: caam - dispose of IRQ mapping only...")
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

In XTS encryption/decryption the plaintext byte size
can be >= AES_BLOCK_SIZE. This patch enable the AES-XTS ciphertext
stealing implementation in ccree driver.
Signed-off-by: NUri Shir <uri.shir@arm.com>
Acked-by: NGilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch actually probes the transform record cache data and
administration RAM sizes, instead of making assumptions, and then
configures the TRC based on the actually probed values.
This allows the driver to work with EIP197 HW that has TRC RAM
sizes different from those of the Marvell EIP197B/D variants.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch derives the result descriptor fetch count from the actual
FIFO size advertised by the hardware. Fetching result descriptors
one at a time is a performance bottleneck for small blocks, especially
on hardware with multiple pipes. Even moreso if the HW has few rings.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch derives the command descriptor fetch count from the actual
FIFO size advertised by the hardware. Fetching command descriptors
one at a time is a performance bottleneck for small blocks, especially
on hardware with multiple pipes. Even moreso if the HW has few rings.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch enables algorithms that did not fit the original 32 bit
FUNCTION_EN register anymore via the FUNCTION2_EN extension reg.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch corrects the configuration of the EIP197_PE_EIP96_TOKEN_CTRL
register. Previous value was wrong and potentially dangerous.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds automatic EIP97/EIP197 detection, so it does not need to
rely on any static value from the device table anymore. In particular,
the static value from the table won't work for PCI devboards that cannot
be further identified save from this direct hardware probing.

The patch also adds automatic host xs endianness detection & correction.
Signed-off-by: NPascal van Leeuwen <pvanleeuwen@verimatrix.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

With the removal of the ENODATA case from padata_get_next, the cpu_index
field is no longer useful, so it can go away.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Padata binds the parallel part of a job to a single CPU and round-robins
over all CPUs in the system for each successive job.  Though the serial
parts rely on per-CPU queues for correct ordering, they're not necessary
for parallel work, and it improves performance to run the job locally on
NUMA machines and let the scheduler pick the CPU within a node on a busy
system.

So, make the parallel workqueue unbound.

Update the parallel workqueue's cpumask when the instance's parallel
cpumask changes.

Now that parallel jobs no longer run on max_active=1 workqueues, two or
more parallel works that hash to the same CPU may run simultaneously,
finish out of order, and so be serialized out of order.  Prevent this by
keeping the works sorted on the reorder list by sequence number and
checking that in the reordering logic.

padata_get_next becomes padata_find_next so it can be reused for the end
of padata_reorder, where it's used to avoid uselessly queueing work when
the next job by sequence number isn't finished yet but a later job that
hashed to the same CPU has.

The ENODATA case in padata_find_next no longer makes sense because
parallel jobs aren't bound to specific CPUs.  The EINPROGRESS case takes
care of the scenario where a parallel job is potentially running on the
same CPU as padata_find_next, and with only one error code left, just
use NULL instead.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

padata currently uses one per-CPU workqueue per instance for all work.

Prepare for running parallel jobs on an unbound workqueue by introducing
dedicated workqueues for parallel and serial work.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

With pcrypt's cpumask no longer used, take the CPU hotplug lock inside
padata_alloc_possible.

Useful later in the series for avoiding nested acquisition of the CPU
hotplug lock in padata when padata_alloc_possible is allocating an
unbound workqueue.

Without this patch, this nested acquisition would happen later in the
series:

      pcrypt_init_padata
        get_online_cpus
        alloc_padata_possible
          alloc_padata
            alloc_workqueue(WQ_UNBOUND)   // later in the series
              alloc_and_link_pwqs
                apply_wqattrs_lock
                  get_online_cpus         // recursive rwsem acquisition
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Now that padata_do_parallel takes care of finding an alternate callback
CPU, there's no need for pcrypt's callback cpumask, so remove it and the
notifier callback that keeps it in sync.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

padata_do_parallel currently returns -EINVAL if the callback CPU isn't
in the callback cpumask.

pcrypt tries to prevent this situation by keeping its own callback
cpumask in sync with padata's and checks that the callback CPU it passes
to padata is valid.  Make padata handle this instead.

padata_do_parallel now takes a pointer to the callback CPU and updates
it for the caller if an alternate CPU is used.  Overall behavior in
terms of which callback CPUs are chosen stays the same.

Prepares for removal of the padata cpumask notifier in pcrypt, which
will fix a lockdep complaint about nested acquisition of the CPU hotplug
lock later in the series.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Change the calling convention for apply_workqueue_attrs to require CPU
hotplug read exclusion.

Avoids lockdep complaints about nested calls to get_online_cpus in a
future patch where padata calls apply_workqueue_attrs when changing
other CPU-hotplug-sensitive data structures with the CPU read lock
already held.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

padata will use these these interfaces in a later patch, so unconfine them.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Move workqueue allocation inside of padata to prepare for further
changes to how padata uses workqueues.

Guarantees the workqueue is created with max_active=1, which padata
relies on to work correctly.  No functional change.
Signed-off-by: NDaniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Add node for CAAM - Cryptographic Acceleration and Assurance Module.
Signed-off-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: NLi Yang <leoyang.li@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Sebastian reports that after commit ff296293 ("random: Support freezable
kthreads in add_hwgenerator_randomness()") we can call might_sleep() when the
task state is TASK_INTERRUPTIBLE (state=1). This leads to the following warning.

 do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000349d1489>] prepare_to_wait_event+0x5a/0x180
 WARNING: CPU: 0 PID: 828 at kernel/sched/core.c:6741 __might_sleep+0x6f/0x80
 Modules linked in:

 CPU: 0 PID: 828 Comm: hwrng Not tainted 5.3.0-rc7-next-20190903+ #46
 RIP: 0010:__might_sleep+0x6f/0x80

 Call Trace:
  kthread_freezable_should_stop+0x1b/0x60
  add_hwgenerator_randomness+0xdd/0x130
  hwrng_fillfn+0xbf/0x120
  kthread+0x10c/0x140
  ret_from_fork+0x27/0x50

We shouldn't call kthread_freezable_should_stop() from deep within the
wait_event code because the task state is still set as
TASK_INTERRUPTIBLE instead of TASK_RUNNING and
kthread_freezable_should_stop() will try to call into the freezer with
the task in the wrong state. Use wait_event_freezable() instead so that
it calls schedule() in the right place and tries to enter the freezer
when the task state is TASK_RUNNING instead.
Reported-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Keerthy <j-keerthy@ti.com>
Fixes: ff296293 ("random: Support freezable kthreads in add_hwgenerator_randomness()")
Signed-off-by: NStephen Boyd <swboyd@chromium.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch fixes a number of warnings encountered when this driver
is built on a 64-bit platform with COMPILE_TEST.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

The RFC4106 key derivation code instantiates an AES cipher transform
to encrypt only a single block before it is freed again. Switch to
the new AES library which is more suitable for such use cases.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

When using single_open() for opening, single_release() should be
used instead of seq_release(), otherwise there is a memory leak.

Fixes: 09ae5d37 ("crypto: zip - Add Compression/Decompression statistics")
Cc: <stable@vger.kernel.org>
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Use kzfree instead of memset() + kfree().
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

With IRQ requesting being managed by devres we need to make sure that
we dispose of IRQ mapping after and not before it is free'd (otherwise
we'll end up with a warning from the kernel). To achieve that simply
convert IRQ mapping to rely on devres as well.

Fixes: f314f12db65c ("crypto: caam - convert caam_jr_init() to use devres")
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Irq_of_parse_and_map will return zero in case of error, so add a error
check for that.
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Use devres to unmap memory and drop explicit de-initialization
code.

NOTE: There's no corresponding unmapping code in caam_jr_remove which
seems like a resource leak.
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

In order to access IP block's registers we need to enable appropriate
clocks first, otherwise we are risking hanging the CPU.

The problem becomes very apparent when trying to use CAAM driver built
as a kernel module. In that case caam_probe() gets called after
clk_disable_unused() which means all of the necessary clocks are
guaranteed to be disabled.

Coincidentally, this change also fixes iomap leak introduced by early
return (instead of "goto iounmap_ctrl") in commit
41fc54afae70 ("crypto: caam - simplfy clock initialization")

Tested on ZII i.MX6Q+ RDU2

Fixes: 176435ad ("crypto: caam - defer probing until QMan is available")
Fixes: 41fc54afae70 ("crypto: caam - simplfy clock initialization")
Signed-off-by: NAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Tested-by: NHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Instead of relying on the CTS template to wrap the accelerated CBC
skcipher, implement the ciphertext stealing part directly.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Update the AES-XTS implementation based on NEON instructions so that it
can deal with inputs whose size is not a multiple of the cipher block
size. This is part of the original XTS specification, but was never
implemented before in the Linux kernel.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Update the AES-XTS implementation based on AES instructions so that it
can deal with inputs whose size is not a multiple of the cipher block
size. This is part of the original XTS specification, but was never
implemented before in the Linux kernel.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Update the AES-XTS implementation based on NEON instructions so that it
can deal with inputs whose size is not a multiple of the cipher block
size. This is part of the original XTS specification, but was never
implemented before in the Linux kernel.

Since the bit slicing driver is only faster if it can operate on at
least 7 blocks of input at the same time, let's reuse the alternate
path we are adding for CTS to process any data tail whose size is
not a multiple of 128 bytes.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Add the missing support for ciphertext stealing in the implementation
of AES-XTS, which is part of the XTS specification but was omitted up
until now due to lack of a need for it.

The asm helpers are updated so they can deal with any input size, as
long as the last full block and the final partial block are presented
at the same time. The glue code is updated so that the common case of
operating on a sector or page is mostly as before. When CTS is needed,
the walk is split up into two pieces, unless the entire input is covered
by a single step.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Since the CTS-CBC code completes synchronously, there is no point in
keeping part of the scratch data it uses in the request context, so
move it to the stack instead.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Optimize away one of the tbl instructions in the decryption path,
which turns out to be unnecessary.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>