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2019-07-17docs: remove extra conf.py filesMauro Carvalho Chehab1-10/+0
Now that the latex_documents are handled automatically, we can remove those extra conf.py files. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-03crypto: doc - Fix formatting of new crypto engine contentHook, Gary1-38/+73
Tidy up the formatting/grammar in crypto_engine.rst. Use bulleted lists where appropriate. Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-03crypto: doc - Add parameter documentationHook, Gary1-1/+1
Fill in missing parameter descriptions for the compression algorithm, then pick them up to document for the compression_alg structure. Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-06-13crypto: doc - improve the skcipher API example codeEric Biggers1-99/+77
Rewrite the skcipher API example, changing it to encrypt a buffer with AES-256-XTS. This addresses various problems with the previous example: - It requests a specific driver "cbc-aes-aesni", which is unusual. Normally users ask for "cbc(aes)", not a specific driver. - It encrypts only a single AES block. For the reader, that doesn't clearly distinguish the "skcipher" API from the "cipher" API. - Showing how to encrypt something with bare CBC is arguably a poor choice of example, as it doesn't follow modern crypto trends. Now, usually authenticated encryption is recommended, in which case the user would use the AEAD API, not skcipher. Disk encryption is still a legitimate use for skcipher, but for that usually XTS is recommended. - Many other bugs and poor coding practices, such as not setting CRYPTO_TFM_REQ_MAY_SLEEP, unnecessarily allocating a heap buffer for the IV, unnecessary NULL checks, using a pointless wrapper struct, and forgetting to set an error code in one case. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-30crypto: hash - remove CRYPTO_ALG_TYPE_DIGESTEric Biggers1-3/+1
Remove the unnecessary constant CRYPTO_ALG_TYPE_DIGEST, which has the same value as CRYPTO_ALG_TYPE_HASH. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25crypto: shash - remove shash_desc::flagsEric Biggers1-1/+0
The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23crypto: skcipher - remove remnants of internal IV generatorsEric Biggers2-35/+5
Remove dead code related to internal IV generators, which are no longer used since they've been replaced with the "seqiv" and "echainiv" templates. The removed code includes: - The "givcipher" (GIVCIPHER) algorithm type. No algorithms are registered with this type anymore, so it's unneeded. - The "const char *geniv" member of aead_alg, ablkcipher_alg, and blkcipher_alg. A few algorithms still set this, but it isn't used anymore except to show via /proc/crypto and CRYPTO_MSG_GETALG. Just hardcode "<default>" or "<none>" in those cases. - The 'skcipher_givcrypt_request' structure, which is never used. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-10-26KEYS: Implement PKCS#8 RSA Private Key parser [ver #2]David Howells1-0/+2
Implement PKCS#8 RSA Private Key format [RFC 5208] parser for the asymmetric key type. For the moment, this will only support unencrypted DER blobs. PEM and decryption can be added later. PKCS#8 keys can be loaded like this: openssl pkcs8 -in private_key.pem -topk8 -nocrypt -outform DER | \ keyctl padd asymmetric foo @s Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Denis Kenzior <denkenz@gmail.com> Tested-by: Denis Kenzior <denkenz@gmail.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-10-26KEYS: Provide missing asymmetric key subops for new key type ops [ver #2]David Howells1-5/+19
Provide the missing asymmetric key subops for new key type ops. This include query, encrypt, decrypt and create signature. Verify signature already exists. Also provided are accessor functions for this: int query_asymmetric_key(const struct key *key, struct kernel_pkey_query *info); int encrypt_blob(struct kernel_pkey_params *params, const void *data, void *enc); int decrypt_blob(struct kernel_pkey_params *params, const void *enc, void *data); int create_signature(struct kernel_pkey_params *params, const void *data, void *enc); The public_key_signature struct gains an encoding field to carry the encoding for verify_signature(). Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Marcel Holtmann <marcel@holtmann.org> Reviewed-by: Denis Kenzior <denkenz@gmail.com> Tested-by: Denis Kenzior <denkenz@gmail.com> Signed-off-by: James Morris <james.morris@microsoft.com>
2018-07-08crypto: remove redundant type flags from tfm allocationEric Biggers1-1/+1
Some crypto API users allocating a tfm with crypto_alloc_$FOO() are also specifying the type flags for $FOO, e.g. crypto_alloc_shash() with CRYPTO_ALG_TYPE_SHASH. But, that's redundant since the crypto API will override any specified type flag/mask with the correct ones. So, remove the unneeded flags. This patch shouldn't change any actual behavior. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-06-15docs: crypto_engine.rst: Fix two parse warningsMauro Carvalho Chehab1-3/+5
./Documentation/crypto/crypto_engine.rst:13: WARNING: Unexpected indentation. ./Documentation/crypto/crypto_engine.rst:15: WARNING: Block quote ends without a blank line; unexpected unindent. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-05-08docs: */index.rst: Add newer documents to their respective index.rstMauro Carvalho Chehab1-0/+1
A number of new docs were added, but they're currently not on the index.rst from the session they're supposed to be, causing Sphinx warnings. Add them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-03-30crypto: doc - clarify hash callbacks state machineHoria Geantă1-0/+8
Add a note that it is perfectly legal to "abandon" a request object: - call .init() and then (as many times) .update() - _not_ call any of .final(), .finup() or .export() at any point in future Link: https://lkml.kernel.org/r/20180222114741.GA27631@gondor.apana.org.au Signed-off-by: Horia Geantă <horia.geanta@nxp.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-02-15crypto: doc - document crypto engine APICorentin LABBE1-0/+48
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03crypto: doc - adapt api sample to use async. op waitGilad Ben-Yossef1-42/+10
The code sample is waiting for an async. crypto op completion. Adapt sample to use the new generic infrastructure to do the same. This also fixes a possible data coruption bug created by the use of wait_for_completion_interruptible() without dealing correctly with an interrupt aborting the wait prior to the async op finishing. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-07-14KEYS: Add documentation for asymmetric keyring restrictionsMat Martineau1-8/+57
Provide more specific examples of keyring restrictions as applied to X.509 signature chain verification. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2017-07-05Merge branch 'linus' of ↵Linus Torvalds2-11/+29
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "Algorithms: - add private key generation to ecdh Drivers: - add generic gcm(aes) to aesni-intel - add SafeXcel EIP197 crypto engine driver - add ecb(aes), cfb(aes) and ecb(des3_ede) to cavium - add support for CNN55XX adapters in cavium - add ctr mode to chcr - add support for gcm(aes) to omap" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (140 commits) crypto: testmgr - Reenable sha1/aes in FIPS mode crypto: ccp - Release locks before returning crypto: cavium/nitrox - dma_mapping_error() returns bool crypto: doc - fix typo in docs Documentation/bindings: Document the SafeXel cryptographic engine driver crypto: caam - fix gfp allocation flags (part II) crypto: caam - fix gfp allocation flags (part I) crypto: drbg - Fixes panic in wait_for_completion call crypto: caam - make of_device_ids const. crypto: vmx - remove unnecessary check crypto: n2 - make of_device_ids const crypto: inside-secure - use the base_end pointer in ring rollback crypto: inside-secure - increase the batch size crypto: inside-secure - only dequeue when needed crypto: inside-secure - get the backlog before dequeueing the request crypto: inside-secure - stop requeueing failed requests crypto: inside-secure - use one queue per hw ring crypto: inside-secure - update the context and request later crypto: inside-secure - align the cipher and hash send functions crypto: inside-secure - optimize DSE bufferability control ...
2017-06-22crypto: doc - fix typo in docsBenjamin Peterson1-1/+1
Signed-off-by: Benjamin Peterson <bp@benjamin.pe> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-06-19crypto: doc - Fixed bugs, added example usage of calc_hash().Kamil Konieczny1-10/+28
- Fixed bugs in example for shash and rng (added missing "*" and " *"). - Corrected pr_info() in calc_hash(). - Added example usage of calc_hash(). - No need for negate PTR_ERR to get error code, as crypto_alloc_rng already returns negative values like ERR_PTR(-ENOMEM). Fixed. Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-05-18Merge remote-tracking branch 'mauro-exp/docbook3' into death-to-docbookJonathan Corbet1-0/+10
Mauro says: This patch series convert the remaining DocBooks to ReST. The first version was originally send as 3 patch series: [PATCH 00/36] Convert DocBook documents to ReST [PATCH 0/5] Convert more books to ReST [PATCH 00/13] Get rid of DocBook The lsm book was added as if it were a text file under Documentation. The plan is to merge it with another file under Documentation/security, after both this series and a security Documentation patch series gets merged. It also adjusts some Sphinx-pedantic errors/warnings on some kernel-doc markups. I also added some patches here to add PDF output for all existing ReST books.
2017-05-18doc: ReSTify keys.txtKees Cook1-1/+1
This creates a new section in the security development index for kernel keys, and adjusts for ReST markup. Cc: David Howells <dhowells@redhat.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-05-16docs-rst: add crypto API book to pdf outputMauro Carvalho Chehab1-0/+10
The crypto API book was added without the bits required to generate PDF output. Add them. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
2017-05-03Merge branch 'next' of ↵Linus Torvalds1-0/+51
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security subsystem updates from James Morris: "Highlights: IMA: - provide ">" and "<" operators for fowner/uid/euid rules KEYS: - add a system blacklist keyring - add KEYCTL_RESTRICT_KEYRING, exposes keyring link restriction functionality to userland via keyctl() LSM: - harden LSM API with __ro_after_init - add prlmit security hook, implement for SELinux - revive security_task_alloc hook TPM: - implement contextual TPM command 'spaces'" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (98 commits) tpm: Fix reference count to main device tpm_tis: convert to using locality callbacks tpm: fix handling of the TPM 2.0 event logs tpm_crb: remove a cruft constant keys: select CONFIG_CRYPTO when selecting DH / KDF apparmor: Make path_max parameter readonly apparmor: fix parameters so that the permission test is bypassed at boot apparmor: fix invalid reference to index variable of iterator line 836 apparmor: use SHASH_DESC_ON_STACK security/apparmor/lsm.c: set debug messages apparmor: fix boolreturn.cocci warnings Smack: Use GFP_KERNEL for smk_netlbl_mls(). smack: fix double free in smack_parse_opts_str() KEYS: add SP800-56A KDF support for DH KEYS: Keyring asymmetric key restrict method with chaining KEYS: Restrict asymmetric key linkage using a specific keychain KEYS: Add a lookup_restriction function for the asymmetric key type KEYS: Add KEYCTL_RESTRICT_KEYRING KEYS: Consistent ordering for __key_link_begin and restrict check KEYS: Add an optional lookup_restriction hook to key_type ...
2017-04-05KEYS: Keyring asymmetric key restrict method with chainingMat Martineau1-1/+6
Add a restrict_link_by_key_or_keyring_chain link restriction that searches for signing keys in the destination keyring in addition to the signing key or keyring designated when the destination keyring was created. Userspace enables this behavior by including the "chain" option in the keyring restriction: keyctl(KEYCTL_RESTRICT_KEYRING, keyring, "asymmetric", "key_or_keyring:<signing key>:chain"); Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-05KEYS: Restrict asymmetric key linkage using a specific keychainMat Martineau1-0/+11
Adds restrict_link_by_signature_keyring(), which uses the restrict_key member of the provided destination_keyring data structure as the key or keyring to search for signing keys. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-04-05KEYS: Add a lookup_restriction function for the asymmetric key typeMat Martineau1-0/+35
Look up asymmetric keyring restriction information using the key-type lookup_restrict hook. Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
2017-03-16crypto: doc - fix typo (struct sdesc)Fabien DESSENNE1-3/+3
Add missing " " in api-samples.rst Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-02-15crypto: doc - fix typoGilad Ben-Yossef1-1/+1
Fix a single letter typo in api-skcipher.rst. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-02-03crypto: doc - Fix hash export state informationRabin Vincent1-1/+1
The documentation states that crypto_ahash_reqsize() provides the size of the state structure used by crypto_ahash_export(). But it's actually crypto_ahash_statesize() which provides this size. Signed-off-by: Rabin Vincent <rabinv@axis.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-12-18Merge tag 'docs-4.10-2' of git://git.lwn.net/linuxLinus Torvalds13-0/+1614
Pull more documentation updates from Jonathan Corbet: "This converts the crypto DocBook to Sphinx" * tag 'docs-4.10-2' of git://git.lwn.net/linux: crypto: doc - optimize compilation crypto: doc - clarify AEAD memory structure crypto: doc - remove crypto_alloc_ablkcipher crypto: doc - add KPP documentation crypto: doc - fix separation of cipher / req API crypto: doc - fix source comments for Sphinx crypto: doc - remove crypto API DocBook crypto: doc - convert crypto API documentation to Sphinx
2016-12-14crypto: doc - optimize compilationStephan Mueller6-401/+23
The :functions: definition allows the specification of multiple function references which prevents parsing the header file multiple times. Reported-by: Jani Nikula <jani.nikula@linux.intel.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-12-14crypto: doc - remove crypto_alloc_ablkcipherStephan Mueller1-3/+0
Remove the documentation reference to crypto_alloc_ablkcipher as the API function call was removed. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-12-14crypto: doc - add KPP documentationStephan Mueller3-0/+99
Add the KPP API documentation to the kernel crypto API Sphinx documentation. This addition includes the documentation of the ECDH and DH helpers which are needed to create the approrpiate input data for the crypto_kpp_set_secret function. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-12-14crypto: doc - fix separation of cipher / req APIStephan Mueller1-12/+12
Keep the cipher API and the request API function documentation in separate sections. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-12-14crypto: doc - convert crypto API documentation to SphinxStephan Mueller12-0/+1896
With the conversion of the kernel crypto API DocBook to Sphinx, the monolithic document is broken up into individual documents. The documentation is unchanged with the exception of a slight reordering to keep the individual document parts self-contained. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-12-01crypt: doc - remove misleading mention of async APIBaruch Siach1-3/+0
The asynchronous API is quite mature. Not mentioning is at all is probably better than saying it is under development. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-12-01crypto: doc - fix header file nameBaruch Siach1-1/+1
Fixes: 8bc618d6a2e0 ("crypto: doc - Use ahash") Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31crypto: doc - Fix typoAndrea Gelmini1-1/+1
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-06crypto: doc - Use ahashHerbert Xu1-9/+14
This patch replaces the crypto_hash example in api-intro.txt with crypto_ahash. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-21KEYS: Merge the type-specific data with the payload dataDavid Howells1-13/+14
Merge the type-specific data with the payload data into one four-word chunk as it seems pointless to keep them separate. Use user_key_payload() for accessing the payloads of overloaded user-defined keys. Signed-off-by: David Howells <dhowells@redhat.com> cc: linux-cifs@vger.kernel.org cc: ecryptfs@vger.kernel.org cc: linux-ext4@vger.kernel.org cc: linux-f2fs-devel@lists.sourceforge.net cc: linux-nfs@vger.kernel.org cc: ceph-devel@vger.kernel.org cc: linux-ima-devel@lists.sourceforge.net
2015-03-09crypto: doc - AEAD / RNG AF_ALG interfaceStephan Mueller1-205/+0
The patch moves the information provided in Documentation/crypto/crypto-API-userspace.txt into a separate chapter in the kernel crypto API DocBook. Some corrections are applied (such as removing a reference to Netlink when the AF_ALG socket is referred to). In addition, the AEAD and RNG interface description is now added. Also, a brief description of the zero-copy interface with an example code snippet is provided. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-13crypto: doc - userspace interface specStephan Mueller1-0/+205
The userspace interface of the kernel crypto API is documented with * a general explanation * a discussion of the memory in-place operation * the description of the message digest API * the description of the symmetric cipher API The documentation refers to libkcapi as a working example on how to use the kernel crypto API from user space. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-07-04drivers/dma: remove unused support for MEMSET operationsBartlomiej Zolnierkiewicz1-1/+0
There have never been any real users of MEMSET operations since they have been introduced in January 2007 by commit 7405f74badf4 ("dmaengine: refactor dmaengine around dma_async_tx_descriptor"). Therefore remove support for them for now, it can be always brought back when needed. [sebastian.hesselbarth@gmail.com: fix drivers/dma/mv_xor] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Cc: Vinod Koul <vinod.koul@intel.com> Acked-by: Dan Williams <djbw@fb.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Olof Johansson <olof@lixom.net> Cc: Kevin Hilman <khilman@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-08KEYS: Document asymmetric key typeDavid Howells1-0/+312
In-source documentation for the asymmetric key type. This will be located in: Documentation/crypto/asymmetric-keys.txt Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-08-30async_tx: add support for asynchronous RAID6 recovery operationsDan Williams1-0/+4
async_raid6_2data_recov() recovers two data disk failures async_raid6_datap_recov() recovers a data disk and the P disk These routines are a port of the synchronous versions found in drivers/md/raid6recov.c. The primary difference is breaking out the xor operations into separate calls to async_xor. Two helper routines are introduced to perform scalar multiplication where needed. async_sum_product() multiplies two sources by scalar coefficients and then sums (xor) the result. async_mult() simply multiplies a single source by a scalar. This implemention also includes, in contrast to the original synchronous-only code, special case handling for the 4-disk and 5-disk array cases. In these situations the default N-disk algorithm will present 0-source or 1-source operations to dma devices. To cover for dma devices where the minimum source count is 2 we implement 4-disk and 5-disk handling in the recovery code. [ Impact: asynchronous raid6 recovery routines for 2data and datap cases ] Cc: Yuri Tikhonov <yur@emcraft.com> Cc: Ilya Yanok <yanok@emcraft.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: David Woodhouse <David.Woodhouse@intel.com> Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-30async_tx: add support for asynchronous GF multiplicationDan Williams1-0/+3
[ Based on an original patch by Yuri Tikhonov ] This adds support for doing asynchronous GF multiplication by adding two additional functions to the async_tx API: async_gen_syndrome() does simultaneous XOR and Galois field multiplication of sources. async_syndrome_val() validates the given source buffers against known P and Q values. When a request is made to run async_pq against more than the hardware maximum number of supported sources we need to reuse the previous generated P and Q values as sources into the next operation. Care must be taken to remove Q from P' and P from Q'. For example to perform a 5 source pq op with hardware that only supports 4 sources at a time the following approach is taken: p, q = PQ(src0, src1, src2, src3, COEF({01}, {02}, {04}, {08})) p', q' = PQ(p, q, q, src4, COEF({00}, {01}, {00}, {10})) p' = p + q + q + src4 = p + src4 q' = {00}*p + {01}*q + {00}*q + {10}*src4 = q + {10}*src4 Note: 4 is the minimum acceptable maxpq otherwise we punt to synchronous-software path. The DMA_PREP_CONTINUE flag indicates to the driver to reuse p and q as sources (in the above manner) and fill the remaining slots up to maxpq with the new sources/coefficients. Note1: Some devices have native support for P+Q continuation and can skip this extra work. Devices with this capability can advertise it with dma_set_maxpq. It is up to each driver how to handle the DMA_PREP_CONTINUE flag. Note2: The api supports disabling the generation of P when generating Q, this is ignored by the synchronous path but is implemented by some dma devices to save unnecessary writes. In this case the continuation algorithm is simplified to only reuse Q as a source. Cc: H. Peter Anvin <hpa@zytor.com> Cc: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-04async_xor: permit callers to pass in a 'dma/page scribble' regionDan Williams1-15/+28
async_xor() needs space to perform dma and page address conversions. In most cases the code can simply reuse the struct page * array because the size of the native pointer matches the size of a dma/page address. In order to support archs where sizeof(dma_addr_t) is larger than sizeof(struct page *), or to preserve the input parameters, we utilize a memory region passed in by the caller. Since the code is now prepared to handle the case where it cannot perform address conversions on the stack, we no longer need the !HIGHMEM64G dependency in drivers/dma/Kconfig. [ Impact: don't clobber input buffers for address conversions ] Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-04async_tx: structify submission arguments, add scribbleDan Williams1-5/+1
Prepare the api for the arrival of a new parameter, 'scribble'. This will allow callers to identify scratchpad memory for dma address or page address conversions. As this adds yet another parameter, take this opportunity to convert the common submission parameters (flags, dependency, callback, and callback argument) into an object that is passed by reference. Also, take this opportunity to fix up the kerneldoc and add notes about the relevant ASYNC_TX_* flags for each routine. [ Impact: moves api pass-by-value parameters to a pass-by-reference struct ] Signed-off-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-06-04async_tx: kill ASYNC_TX_DEP_ACK flagDan Williams1-5/+4
In support of inter-channel chaining async_tx utilizes an ack flag to gate whether a dependent operation can be chained to another. While the flag is not set the chain can be considered open for appending. Setting the ack flag closes the chain and flags the descriptor for garbage collection. The ASYNC_TX_DEP_ACK flag essentially means "close the chain after adding this dependency". Since each operation can only have one child the api now implicitly sets the ack flag at dependency submission time. This removes an unnecessary management burden from clients of the api. [ Impact: clean up and enforce one dependency per operation ] Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-04-09async_tx: rename zero_sum to valDan Williams1-7/+7
'zero_sum' does not properly describe the operation of generating parity and checking that it validates against an existing buffer. Change the name of the operation to 'val' (for 'validate'). This is in anticipation of the p+q case where it is a requirement to identify the target parity buffers separately from the source buffers, because the target parity buffers will not have corresponding pq coefficients. Reviewed-by: Andre Noll <maan@systemlinux.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>