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Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git…
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…/herbert/crypto-2.6

Pull crypto updates from Herbert Xu:
 "API:
   - Removed CRYPTO_TFM_RES flags
   - Extended spawn grabbing to all algorithm types
   - Moved hash descsize verification into API code

  Algorithms:
   - Fixed recursive pcrypt dead-lock
   - Added new 32 and 64-bit generic versions of poly1305
   - Added cryptogams implementation of x86/poly1305

  Drivers:
   - Added support for i.MX8M Mini in caam
   - Added support for i.MX8M Nano in caam
   - Added support for i.MX8M Plus in caam
   - Added support for A33 variant of SS in sun4i-ss
   - Added TEE support for Raven Ridge in ccp
   - Added in-kernel API to submit TEE commands in ccp
   - Added AMD-TEE driver
   - Added support for BCM2711 in iproc-rng200
   - Added support for AES256-GCM based ciphers for chtls
   - Added aead support on SEC2 in hisilicon"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (244 commits)
  crypto: arm/chacha - fix build failured when kernel mode NEON is disabled
  crypto: caam - add support for i.MX8M Plus
  crypto: x86/poly1305 - emit does base conversion itself
  crypto: hisilicon - fix spelling mistake "disgest" -> "digest"
  crypto: chacha20poly1305 - add back missing test vectors and test chunking
  crypto: x86/poly1305 - fix .gitignore typo
  tee: fix memory allocation failure checks on drv_data and amdtee
  crypto: ccree - erase unneeded inline funcs
  crypto: ccree - make cc_pm_put_suspend() void
  crypto: ccree - split overloaded usage of irq field
  crypto: ccree - fix PM race condition
  crypto: ccree - fix FDE descriptor sequence
  crypto: ccree - cc_do_send_request() is void func
  crypto: ccree - fix pm wrongful error reporting
  crypto: ccree - turn errors to debug msgs
  crypto: ccree - fix AEAD decrypt auth fail
  crypto: ccree - fix typo in comment
  crypto: ccree - fix typos in error msgs
  crypto: atmel-{aes,sha,tdes} - Retire crypto_platform_data
  crypto: x86/sha - Eliminate casts on asm implementations
  ...
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torvalds committed Jan 28, 2020
2 parents 6835398 + 0bc8176 commit a78208e
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1 change: 1 addition & 0 deletions .mailmap
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Expand Up @@ -139,6 +139,7 @@ Juha Yrjola <at solidboot.com>
Juha Yrjola <[email protected]>
Juha Yrjola <[email protected]>
Julien Thierry <[email protected]> <[email protected]>
Kamil Konieczny <[email protected]> <[email protected]>
Kay Sievers <[email protected]>
Kenneth W Chen <[email protected]>
Konstantin Khlebnikov <[email protected]> <[email protected]>
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1 change: 1 addition & 0 deletions Documentation/core-api/index.rst
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Expand Up @@ -39,6 +39,7 @@ Core utilities
../RCU/index
gcc-plugins
symbol-namespaces
padata


Interfaces for kernel debugging
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169 changes: 169 additions & 0 deletions Documentation/core-api/padata.rst
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@@ -0,0 +1,169 @@
.. SPDX-License-Identifier: GPL-2.0
=======================================
The padata parallel execution mechanism
=======================================

:Date: December 2019

Padata is a mechanism by which the kernel can farm jobs out to be done in
parallel on multiple CPUs while retaining their ordering. It was developed for
use with the IPsec code, which needs to be able to perform encryption and
decryption on large numbers of packets without reordering those packets. The
crypto developers made a point of writing padata in a sufficiently general
fashion that it could be put to other uses as well.

Usage
=====

Initializing
------------

The first step in using padata is to set up a padata_instance structure for
overall control of how jobs are to be run::

#include <linux/padata.h>

struct padata_instance *padata_alloc_possible(const char *name);

'name' simply identifies the instance.

There are functions for enabling and disabling the instance::

int padata_start(struct padata_instance *pinst);
void padata_stop(struct padata_instance *pinst);

These functions are setting or clearing the "PADATA_INIT" flag; if that flag is
not set, other functions will refuse to work. padata_start() returns zero on
success (flag set) or -EINVAL if the padata cpumask contains no active CPU
(flag not set). padata_stop() clears the flag and blocks until the padata
instance is unused.

Finally, complete padata initialization by allocating a padata_shell::

struct padata_shell *padata_alloc_shell(struct padata_instance *pinst);

A padata_shell is used to submit a job to padata and allows a series of such
jobs to be serialized independently. A padata_instance may have one or more
padata_shells associated with it, each allowing a separate series of jobs.

Modifying cpumasks
------------------

The CPUs used to run jobs can be changed in two ways, programatically with
padata_set_cpumask() or via sysfs. The former is defined::

int padata_set_cpumask(struct padata_instance *pinst, int cpumask_type,
cpumask_var_t cpumask);

Here cpumask_type is one of PADATA_CPU_PARALLEL or PADATA_CPU_SERIAL, where a
parallel cpumask describes which processors will be used to execute jobs
submitted to this instance in parallel and a serial cpumask defines which
processors are allowed to be used as the serialization callback processor.
cpumask specifies the new cpumask to use.

There may be sysfs files for an instance's cpumasks. For example, pcrypt's
live in /sys/kernel/pcrypt/<instance-name>. Within an instance's directory
there are two files, parallel_cpumask and serial_cpumask, and either cpumask
may be changed by echoing a bitmask into the file, for example::

echo f > /sys/kernel/pcrypt/pencrypt/parallel_cpumask

Reading one of these files shows the user-supplied cpumask, which may be
different from the 'usable' cpumask.

Padata maintains two pairs of cpumasks internally, the user-supplied cpumasks
and the 'usable' cpumasks. (Each pair consists of a parallel and a serial
cpumask.) The user-supplied cpumasks default to all possible CPUs on instance
allocation and may be changed as above. The usable cpumasks are always a
subset of the user-supplied cpumasks and contain only the online CPUs in the
user-supplied masks; these are the cpumasks padata actually uses. So it is
legal to supply a cpumask to padata that contains offline CPUs. Once an
offline CPU in the user-supplied cpumask comes online, padata is going to use
it.

Changing the CPU masks are expensive operations, so it should not be done with
great frequency.

Running A Job
-------------

Actually submitting work to the padata instance requires the creation of a
padata_priv structure, which represents one job::

struct padata_priv {
/* Other stuff here... */
void (*parallel)(struct padata_priv *padata);
void (*serial)(struct padata_priv *padata);
};

This structure will almost certainly be embedded within some larger
structure specific to the work to be done. Most of its fields are private to
padata, but the structure should be zeroed at initialisation time, and the
parallel() and serial() functions should be provided. Those functions will
be called in the process of getting the work done as we will see
momentarily.

The submission of the job is done with::

int padata_do_parallel(struct padata_shell *ps,
struct padata_priv *padata, int *cb_cpu);

The ps and padata structures must be set up as described above; cb_cpu
points to the preferred CPU to be used for the final callback when the job is
done; it must be in the current instance's CPU mask (if not the cb_cpu pointer
is updated to point to the CPU actually chosen). The return value from
padata_do_parallel() is zero on success, indicating that the job is in
progress. -EBUSY means that somebody, somewhere else is messing with the
instance's CPU mask, while -EINVAL is a complaint about cb_cpu not being in the
serial cpumask, no online CPUs in the parallel or serial cpumasks, or a stopped
instance.

Each job submitted to padata_do_parallel() will, in turn, be passed to
exactly one call to the above-mentioned parallel() function, on one CPU, so
true parallelism is achieved by submitting multiple jobs. parallel() runs with
software interrupts disabled and thus cannot sleep. The parallel()
function gets the padata_priv structure pointer as its lone parameter;
information about the actual work to be done is probably obtained by using
container_of() to find the enclosing structure.

Note that parallel() has no return value; the padata subsystem assumes that
parallel() will take responsibility for the job from this point. The job
need not be completed during this call, but, if parallel() leaves work
outstanding, it should be prepared to be called again with a new job before
the previous one completes.

Serializing Jobs
----------------

When a job does complete, parallel() (or whatever function actually finishes
the work) should inform padata of the fact with a call to::

void padata_do_serial(struct padata_priv *padata);

At some point in the future, padata_do_serial() will trigger a call to the
serial() function in the padata_priv structure. That call will happen on
the CPU requested in the initial call to padata_do_parallel(); it, too, is
run with local software interrupts disabled.
Note that this call may be deferred for a while since the padata code takes
pains to ensure that jobs are completed in the order in which they were
submitted.

Destroying
----------

Cleaning up a padata instance predictably involves calling the three free
functions that correspond to the allocation in reverse::

void padata_free_shell(struct padata_shell *ps);
void padata_stop(struct padata_instance *pinst);
void padata_free(struct padata_instance *pinst);

It is the user's responsibility to ensure all outstanding jobs are complete
before any of the above are called.

Interface
=========

.. kernel-doc:: include/linux/padata.h
.. kernel-doc:: kernel/padata.c
38 changes: 14 additions & 24 deletions Documentation/crypto/devel-algos.rst
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Expand Up @@ -31,33 +31,23 @@ The counterparts to those functions are listed below.

::

int crypto_unregister_alg(struct crypto_alg *alg);
int crypto_unregister_algs(struct crypto_alg *algs, int count);
void crypto_unregister_alg(struct crypto_alg *alg);
void crypto_unregister_algs(struct crypto_alg *algs, int count);


Notice that both registration and unregistration functions do return a
value, so make sure to handle errors. A return code of zero implies
success. Any return code < 0 implies an error.
The registration functions return 0 on success, or a negative errno
value on failure. crypto_register_algs() succeeds only if it
successfully registered all the given algorithms; if it fails partway
through, then any changes are rolled back.

The bulk registration/unregistration functions register/unregister each
transformation in the given array of length count. They handle errors as
follows:

- crypto_register_algs() succeeds if and only if it successfully
registers all the given transformations. If an error occurs partway
through, then it rolls back successful registrations before returning
the error code. Note that if a driver needs to handle registration
errors for individual transformations, then it will need to use the
non-bulk function crypto_register_alg() instead.

- crypto_unregister_algs() tries to unregister all the given
transformations, continuing on error. It logs errors and always
returns zero.
The unregistration functions always succeed, so they don't have a
return value. Don't try to unregister algorithms that aren't
currently registered.

Single-Block Symmetric Ciphers [CIPHER]
---------------------------------------

Example of transformations: aes, arc4, ...
Example of transformations: aes, serpent, ...

This section describes the simplest of all transformation
implementations, that being the CIPHER type used for symmetric ciphers.
Expand Down Expand Up @@ -108,7 +98,7 @@ is also valid:
Multi-Block Ciphers
-------------------

Example of transformations: cbc(aes), ecb(arc4), ...
Example of transformations: cbc(aes), chacha20, ...

This section describes the multi-block cipher transformation
implementations. The multi-block ciphers are used for transformations
Expand Down Expand Up @@ -169,10 +159,10 @@ are as follows:

::

int crypto_unregister_ahash(struct ahash_alg *alg);
void crypto_unregister_ahash(struct ahash_alg *alg);

int crypto_unregister_shash(struct shash_alg *alg);
int crypto_unregister_shashes(struct shash_alg *algs, int count);
void crypto_unregister_shash(struct shash_alg *alg);
void crypto_unregister_shashes(struct shash_alg *algs, int count);


Cipher Definition With struct shash_alg and ahash_alg
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Expand Up @@ -2,6 +2,7 @@ HWRNG support for the iproc-rng200 driver

Required properties:
- compatible : Must be one of:
"brcm,bcm2711-rng200"
"brcm,bcm7211-rng200"
"brcm,bcm7278-rng200"
"brcm,iproc-rng200"
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