From patchwork Mon May 8 20:07:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zanussi, Tom" X-Patchwork-Id: 13235017 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61ED7C7EE22 for ; Mon, 8 May 2023 20:08:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234282AbjEHUIk (ORCPT ); Mon, 8 May 2023 16:08:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234067AbjEHUIP (ORCPT ); Mon, 8 May 2023 16:08:15 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26B7A6EA2; Mon, 8 May 2023 13:07:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1683576478; x=1715112478; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=qfiiTbL0IBBRpU0vw3v16yQeSWCDx4nuhaamLWLsflQ=; b=G1ycyJ+tjIK0VkiQYWXu0ADEe/T6CGvwaofN3+b1MOmLJC0TgjLQ/oYA oFMTnDSwY5JRbMIhuZL0XKGZhHBHqXh3WMB/Mh71kIKnufZmTWD59rCN3 8zsFn6121wr6w2fp4DkpHUWzmU57ccwR62IbolKBGKCEvg4rLz+xYstgK QtT7nfO4xu7uKbn9dLZyCe2swku/LvVtP6KFRAk7kXWQzXJW3tL5BXKsk qYH0JbtFcGfjVwGed6zWY8wOO8w4OmWKE0UcaYH84SZdng5WHr6dt2Qg3 nOq/vEVLLILPcfk9VQ5w8MbrYw9crhrYct8yGXBoP+TtR9O8OWDnGj/W3 g==; X-IronPort-AV: E=McAfee;i="6600,9927,10704"; a="348573671" X-IronPort-AV: E=Sophos;i="5.99,259,1677571200"; d="scan'208";a="348573671" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2023 13:07:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10704"; a="788241656" X-IronPort-AV: E=Sophos;i="5.99,259,1677571200"; d="scan'208";a="788241656" Received: from sajmal-mobl1.amr.corp.intel.com (HELO tzanussi-mobl1.intel.com) ([10.212.74.4]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2023 13:07:55 -0700 From: Tom Zanussi To: herbert@gondor.apana.org.au, davem@davemloft.net, fenghua.yu@intel.com, vkoul@kernel.org Cc: dave.jiang@intel.com, tony.luck@intel.com, wajdi.k.feghali@intel.com, james.guilford@intel.com, kanchana.p.sridhar@intel.com, giovanni.cabiddu@intel.com, linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, dmaengine@vger.kernel.org Subject: [PATCH v4 08/15] crypto: iaa - Add IAA Compression Accelerator Documentation Date: Mon, 8 May 2023 15:07:30 -0500 Message-Id: <5800baedf4b137d603c935a5c0b667a604eaebc3.1683573703.git.zanussi@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Because the IAA Compression Accelerator requires significant user setup in order to be used properly, this adds documentation on the iaa_crypto driver including setup, usage, and examples. Signed-off-by: Tom Zanussi --- .../driver-api/crypto/iaa/iaa-crypto.rst | 640 ++++++++++++++++++ Documentation/driver-api/crypto/iaa/index.rst | 20 + Documentation/driver-api/crypto/index.rst | 20 + Documentation/driver-api/index.rst | 1 + 4 files changed, 681 insertions(+) create mode 100644 Documentation/driver-api/crypto/iaa/iaa-crypto.rst create mode 100644 Documentation/driver-api/crypto/iaa/index.rst create mode 100644 Documentation/driver-api/crypto/index.rst diff --git a/Documentation/driver-api/crypto/iaa/iaa-crypto.rst b/Documentation/driver-api/crypto/iaa/iaa-crypto.rst new file mode 100644 index 000000000000..a6a716f8b906 --- /dev/null +++ b/Documentation/driver-api/crypto/iaa/iaa-crypto.rst @@ -0,0 +1,640 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================================= +IAA Compression Accelerator Crypto Driver +========================================= + +Tom Zanussi + +The IAA crypto driver supports compression/decompression compatible +with the DEFLATE compression standard described in RFC 1951, which is +the compression/decompression algorithm exported by this module. + +The IAA hardware spec can be found here: + + https://cdrdv2.intel.com/v1/dl/getContent/721858 + +The iaa_crypto driver is designed to work as a layer underneath +higher-level compression devices such as zswap. + +Users can select IAA compress/decompress acceleration by specifying +'iaa_crypto' as the compression algorithm to use by whatever facility +allows compression algorithms to be selected. + +For example, a zswap device can select iaa_crypto via:: + + # echo iaa_crypto > /sys/module/zswap/parameters/compressor + + +Config options and other setup +============================== + +The IAA crypto driver is available via menuconfig using the following +path:: + + Cryptographic API -> Hardware crypto devices -> Support for Intel(R) IAA Compression Accelerator + +In the configuration file the option called CONFIG_CRYPTO_DEV_IAA_CRYPTO. + +The IAA crypto driver also supports statistics, which are available +via menuconfig using the following path:: + + Cryptographic API -> Hardware crypto devices -> Support for Intel(R) IAA Compression -> Enable Intel(R) IAA Compression Accelerator Statistics + +In the configuration file the option called CONFIG_CRYPTO_DEV_IAA_CRYPTO_STATS. + +The following config options should also be enabled:: + + CONFIG_IRQ_REMAP=y + CONFIG_INTEL_IOMMU=y + CONFIG_INTEL_IOMMU_SVM=y + CONFIG_PCI_ATS=y + CONFIG_PCI_PRI=y + CONFIG_PCI_PASID=y + CONFIG_INTEL_IDXD=m + CONFIG_INTEL_IDXD_SVM=y + +IAA is one of the first Intel accelerator IPs that can work in +conjunction with the Intel IOMMU. There are multiple modes that exist +for testing. Based on IOMMU configuration, there are 3 modes:: + + - Scalable + - Legacy + - No IOMMU + + +Scalable mode +------------- + +Scalable mode supports Shared Virtual Memory (SVM or SVA). It is +entered when using the kernel boot commandline:: + + intel_iommu=on,sm_on + +with VT-d turned on in BIOS. + +With scalable mode, both shared and dedicated workqueues are available +for use. + +For scalable mode, the following BIOS settings should be enabled:: + + Socket Configuration > IIO Configuration > Intel VT for Directed I/O (VT-d) > Intel VT for Directed I/O + + Socket Configuration > IIO Configuration > PCIe ENQCMD > ENQCMDS + + +Legacy mode +----------- + +Legacy mode is entered when using the kernel boot commandline:: + + intel_iommu=off, intel_iommu=on + +or VT-d is not turned on in BIOS. + +If you have booted into Linux and not sure if VT-d is on, do a "dmesg +| grep -i dmar". If you don't see a number of DMAR devices enumerated, +most likely VT-d is not on. + +With legacy mode, only dedicated workqueues are available for use. + + +No IOMMU mode +------------- + +No IOMMU mode is entered when using the kernel boot commandline:: + + iommu=off. + +With no IOMMU mode, only dedicated workqueues are available for use. + + +Usage +===== + +accel-config +------------ + +Unlike typical drivers, the iaa_crypto driver does not enable the +device on driver load. Due to complexity and configurability of the +accelerator devices, it was a design decision to have the user +configure the device and manually enable the desired devices and +workqueues. + +The userspace tool to help doing that is called accel-config. Using +accel-config to configure device or loading a previously saved config +is highly recommended. The device can be controlled via sysfs +directly but comes with the warning that do this ONLY if you know +exactly what you are doing. This document will not cover the sysfs +interface but assumes you will be using accel-config. + +The accel-config tool along with instructions for building it can be +found here: + + https://github.com/intel/idxd-config/#readme + + +Typical usage +------------- + +In order for the iaa_crypto module to actually do any +compression/decompression work on behalf of a facility, one or more +IAA workqueues need to be bound to the iaa_crypto driver. + +For instance, here's an example of configuring an IAA workqueue and +binding it to the iaa_crypto driver (note that device names are +specified as 'iax' rather than 'iaa' - this is because upstream still +has the old 'iax' device naming in place) :: + + # configure wq1.0 + + accel-config config-wq --group-id=0 --mode=dedicated --type=kernel --name="iaa_crypto" --device_name="crypto" iax1/wq1.0 + + # enable IAA device iax1 + + accel-config enable-device iax1 + + # enable wq1.0 on IAX device iax1 + + accel-config enable-wq iax1/wq1.0 + +Whenever a new workqueue is bound to or unbound from the iaa_crypto +driver, the available workqueues are 'rebalanced' such that work +submitted from a particular CPU is given to the most appropriate +workqueue available. Current best practice is to configure and bind +at least one workqueue for each IAA device, but as long as there is at +least one workqueue configured and bound to any IAA device in the +system, the iaa_crypto driver will work, albeit most likely not as +efficiently. + +The IAA crypto algorigthms is operational and compression and +decompression operations are fully enabled following the successful +binding of the first IAA workqueue to the iaa_crypto driver. + +Similarly, the IAA crypto algorithm is not operational and compression +and decompression operations are disabled following the unbinding of +the last IAA worqueue to the iaa_crypto driver. + +As a result, the iaa_crypto crypto algorithm and thus the IAA hardware +are only available when one or more workques are bound to the +iaa_crypto driver. + +When there are no IAA workqueues bound to the driver, the IAA crypto +algorithm can be unregistered by removing the module. + + +Driver attributes +----------------- + +There are a few user-configurable driver attributes that can be used +to configure various modes of operation. They're listed below, along +with their default values. To set any of these attributes, echo the +appropriate values to the attribute file located under +/sys/bus/dsa/drivers/crypto/ + + - verify_compress + + Toggle compression verification. If set, each compress will be + internally decompressed and the contents verified, returning error + codes if unsuccessful. This can be toggled with 0/1: + + echo 0 > /sys/bus/dsa/drivers/crypto/verify_compress + + The default setting is '1' - verify all compresses. + + - compression_mode + + Select compression mode to be used by all compresses and + decompresses. There are a number ofcompression modes available, + each identified by a unique string. These can be selected by + echoing the string to the 'compression_mode' driver attribute. + Currently, there are only two compression modes available, + 'canned' and 'fixed' modes. + + The 'fixed' compression mode implements the compression scheme + specified by RFC 1951. + + The 'canned' compression mode implements a good general-purpose + compression scheme whose tables were generated from statistics + derived from a wide variety of SPEC17 workloads. It provides much + better overall characteristics than the existing deflate-1951 + tables implemented by 'fixed'. + + Either 'fixed' or 'canned' modes can be chosen as the mode to be used + for compression/decompression via the iaa_crypto compression_mode + iaa_crypto driver attribute: + + echo "canned" > /sys/bus/dsa/drivers/crypto/compression_mode + + The default setting is 'fixed'. + + - sync_mode + + Select mode to be used to wait for completion of each compresses + and decompress operation. + + The crypto async interface support implemented by iaa_crypto + provides an implementation that satisfies the interface but does + so in a synchronous manner - it fills and submits the IDXD + descriptor and then loops around waiting for it to complete before + returning. This isn't a problem at the moment, since all existing + callers (e.g. zswap) wrap any asynchronous callees in a + synchronous wrapper anyway. + + The iaa_crypto driver does however provide true asynchronous + support for callers that can make use of it. In this mode, it + fills and submits the IDXD descriptor, then returns immediately + with -EINPROGRESS. The caller can then either poll for completion + itself, which requires specific code in the caller which currently + nothing in the upstream kernel implements, or go to sleep and wait + for an interrupt signaling completion. This latter mode is + supported by current users in the kernel such as zswap via + synchronous wrappers. Although it is supported this mode is + significantly slower than the synchronous mode that does the + polling in the iaa_crypto driver previously mentioned. + + This mode can be enabled by writing 'async_irq' to the sync_mode + iaa_crypto driver attribute: + + echo async_irq > /sys/bus/dsa/drivers/crypto/sync_mode + + Async mode without interrupts (caller must poll) can be enabled by + writing 'async' to it: + + echo async > /sys/bus/dsa/drivers/crypto/sync_mode + + The mode that does the polling in the iaa_crypto driver can be + enabled by writing 'sync' to it: + + echo sync > /sys/bus/dsa/drivers/crypto/sync_mode + + The default mode is 'sync'. + + +Statistics +========== + +If the optional debugfs statistics support is enabled, the IAA crypto +driver will generate statistics which can be accessed in debugfs at:: + + # ls -al /sys/kernel/debug/iaa-crypto/ + total 0 + drwxr-xr-x 2 root root 0 Mar 3 09:35 . + drwx------ 47 root root 0 Mar 3 09:35 .. + -rw-r--r-- 1 root root 0 Mar 3 09:35 max_acomp_delay_ns + -rw-r--r-- 1 root root 0 Mar 3 09:35 max_adecomp_delay_ns + -rw-r--r-- 1 root root 0 Mar 3 09:35 max_comp_delay_ns + -rw-r--r-- 1 root root 0 Mar 3 09:35 max_decomp_delay_ns + -rw-r--r-- 1 root root 0 Mar 3 09:35 stats_reset + -rw-r--r-- 1 root root 0 Mar 3 09:35 total_comp_bytes_out + -rw-r--r-- 1 root root 0 Mar 3 09:35 total_comp_calls + -rw-r--r-- 1 root root 0 Mar 3 09:35 total_decomp_bytes_in + -rw-r--r-- 1 root root 0 Mar 3 09:35 total_decomp_calls + -rw-r--r-- 1 root root 0 Mar 3 09:35 wq_stats + +Most of the above statisticss are self-explanatory. The wq_stats file +shows per-wq stats, a set for each iaa device and wq in addition to +some global stats:: + + # cat wq_stats + global stats: + total_comp_calls: 100 + total_decomp_calls: 100 + total_comp_bytes_out: 22800 + total_decomp_bytes_in: 22800 + total_completion_einval_errors: 0 + total_completion_timeout_errors: 0 + total_completion_comp_buf_overflow_errors: 0 + + iaa device: + id: 1 + n_wqs: 1 + comp_calls: 0 + comp_bytes: 0 + decomp_calls: 0 + decomp_bytes: 0 + wqs: + name: iaa_crypto + comp_calls: 0 + comp_bytes: 0 + decomp_calls: 0 + decomp_bytes: 0 + + iaa device: + id: 3 + n_wqs: 1 + comp_calls: 0 + comp_bytes: 0 + decomp_calls: 0 + decomp_bytes: 0 + wqs: + name: iaa_crypto + comp_calls: 0 + comp_bytes: 0 + decomp_calls: 0 + decomp_bytes: 0 + + iaa device: + id: 5 + n_wqs: 1 + comp_calls: 100 + comp_bytes: 22800 + decomp_calls: 100 + decomp_bytes: 22800 + wqs: + name: iaa_crypto + comp_calls: 100 + comp_bytes: 22800 + decomp_calls: 100 + decomp_bytes: 22800 + +Writing 0 to 'stats_reset' resets all the stats, including the +per-device and per-wq stats:: + + # echo 0 > stats_reset + # cat wq_stats + global stats: + total_comp_calls: 0 + total_decomp_calls: 0 + total_comp_bytes_out: 0 + total_decomp_bytes_in: 0 + total_completion_einval_errors: 0 + total_completion_timeout_errors: 0 + total_completion_comp_buf_overflow_errors: 0 + ... + + +Use cases +========= + +Simple zswap test +----------------- + +For this example, the kernel should be configured according to the +dedicated mode options described above, and zswap should be enabled as +well:: + + CONFIG_ZSWAP=y + +This is a simple test that uses iaa_compress as the compressor for a +swap (zswap) device. It sets up the zswap device and then uses the +memory_memadvise program listed below to forcibly swap out and in a +specified number of pages, demonstrating both compress and decompress. + +The zswap test expects the work queues for each IAA device on the +system to be configured properly as a kernel workqueue with a +workqueue driver_name of "crypto". + +The first step is to make sure the iaa_crypto module is loaded:: + + modprobe iaa_crypto + +Following that the IAA device(s) should be configured and enabled. + +The zswap test expects the work queues for each IAA device on the +system to be configured properly as a kernel workqueue with a +workqueue driver_name of "crypto". + +The below script automatically does that:: + + #!/bin/bash + + echo "IAA devices:" + lspci -d:0cfe + echo "# IAA devices:" + lspci -d:0cfe | wc -l + + # + # count iaa instances + # + iaa_dev_id="0cfe" + num_iaa=$(lspci -d:${iaa_dev_id} | wc -l) + echo "Found ${num_iaa} IAA instances" + + # + # disable iaa wqs and devices + # + echo "Disable IAA" + + for ((i = 1; i < ${num_iaa} * 2; i += 2)); do + echo disable wq iax${i}/wq${i}.0 + accel-config disable-wq iax${i}/wq${i}.0 + echo disable iaa iax${i} + accel-config disable-device iax${i} + done + + echo "End Disable IAA" + + # + # configure iaa wqs and devices + # + echo "Configure IAA" + for ((i = 1; i < ${num_iaa} * 2; i += 2)); do + accel-config config-wq --group-id=0 --mode=dedicated --size=128 --priority=10 --type=kernel --name="iaa_crypto" --driver_name="crypto" iax${i}/wq${i} + done + + echo "End Configure IAA" + + # + # enable iaa wqs and devices + # + echo "Enable IAA" + + for ((i = 1; i < ${num_iaa} * 2; i += 2)); do + echo enable iaa iaa${i} + accel-config enable-device iaa${i} + echo enable wq iaa${i}/wq${i}.0 + accel-config enable-wq iaa${i}/wq${i}.0 + done + + echo "End Enable IAA" + +When the workqueues are bound to the iaa_crypto driver, you should +see something similar to the following in dmesg output if you've +enabled debug output (echo -n 'module iaa_crypto +p' > +/sys/kernel/debug/dynamic_debug/control):: + + [ 60.752344] idxd 0000:f6:02.0: add_iaa_wq: added wq 000000004068d14d to iaa 00000000c9585ba2, n_wq 1 + [ 60.752346] iaa_crypto: rebalance_wq_table: nr_nodes=2, nr_cpus 160, nr_iaa 8, cpus_per_iaa 20 + [ 60.752347] iaa_crypto: rebalance_wq_table: iaa=0 + [ 60.752349] idxd 0000:6a:02.0: request_iaa_wq: getting wq from iaa_device 0000000042d7bc52 (0) + [ 60.752350] idxd 0000:6a:02.0: request_iaa_wq: returning unused wq 00000000c8bb4452 (0) from iaa device 0000000042d7bc52 (0) + [ 60.752352] iaa_crypto: rebalance_wq_table: assigned wq for cpu=0, node=0 = wq 00000000c8bb4452 + [ 60.752354] iaa_crypto: rebalance_wq_table: iaa=0 + [ 60.752355] idxd 0000:6a:02.0: request_iaa_wq: getting wq from iaa_device 0000000042d7bc52 (0) + [ 60.752356] idxd 0000:6a:02.0: request_iaa_wq: returning unused wq 00000000c8bb4452 (0) from iaa device 0000000042d7bc52 (0) + [ 60.752358] iaa_crypto: rebalance_wq_table: assigned wq for cpu=1, node=0 = wq 00000000c8bb4452 + [ 60.752359] iaa_crypto: rebalance_wq_table: iaa=0 + [ 60.752360] idxd 0000:6a:02.0: request_iaa_wq: getting wq from iaa_device 0000000042d7bc52 (0) + [ 60.752361] idxd 0000:6a:02.0: request_iaa_wq: returning unused wq 00000000c8bb4452 (0) from iaa device 0000000042d7bc52 (0) + [ 60.752362] iaa_crypto: rebalance_wq_table: assigned wq for cpu=2, node=0 = wq 00000000c8bb4452 + [ 60.752364] iaa_crypto: rebalance_wq_table: iaa=0 + . + . + . + +Once the workqueues and devices have been enabled, the iaa_crypto +algorithm is enabled and available. When the iaa_crypto algorithm has +been successfully enabled, you should see the following dmesg output:: + + [ 64.893759] iaa_crypto: iaa_crypto_enable: iaa_crypto now ENABLED + +Now run the following zswap-specific setup commands:: + + echo 0 > /sys/module/zswap/parameters/enabled + echo 50 > /sys/module/zswap/parameters/max_pool_percent + echo iaa_crypto > /sys/module/zswap/parameters/compressor + echo zsmalloc > /sys/module/zswap/parameters/zpool + echo 1 > /sys/module/zswap/parameters/enabled + echo 0 > /sys/module/zswap/parameters/same_filled_pages_enabled + + echo 100 > /proc/sys/vm/swappiness + echo never > /sys/kernel/mm/transparent_hugepage/enabled + echo 1 > /proc/sys/vm/overcommit_memory + +Finally, you can now run the zswap workload you want to measure. For +example, using the code below, the following command will swap in and +out 100 pages:: + + ./memory_madvise 100 + + Allocating 100 pages to swap in/out + Swapping out 100 pages + Swapping in 100 pages + Swapped out and in 100 pages + +You should see something like the following in the dmesg output if +you've enabled debug output (echo -n 'module iaa_crypto +p' > +/sys/kernel/debug/dynamic_debug/control):: + + [ 404.202972] idxd 0000:e7:02.0: iaa_comp_acompress: dma_map_sg, src_addr 223925c000, nr_sgs 1, req->src 00000000ee7cb5e6, req->slen 4096, sg_dma_len(sg) 4096 + [ 404.202973] idxd 0000:e7:02.0: iaa_comp_acompress: dma_map_sg, dst_addr 21dadf8000, nr_sgs 1, req->dst 000000008d6acea8, req->dlen 4096, sg_dma_len(sg) 8192 + [ 404.202975] idxd 0000:e7:02.0: iaa_compress: desc->src1_addr 223925c000, desc->src1_size 4096, desc->dst_addr 21dadf8000, desc->max_dst_size 4096, desc->src2_addr 2203543000, desc->src2_size 1568 + [ 404.202981] idxd 0000:e7:02.0: iaa_compress_verify: (verify) desc->src1_addr 21dadf8000, desc->src1_size 228, desc->dst_addr 223925c000, desc->max_dst_size 4096, desc->src2_addr 0, desc->src2_size 0 + [ 409.203227] idxd 0000:e7:02.0: iaa_comp_adecompress: dma_map_sg, src_addr 21ddd8b100, nr_sgs 1, req->src 0000000084adab64, req->slen 228, sg_dma_len(sg) 228 + [ 409.203235] idxd 0000:e7:02.0: iaa_comp_adecompress: dma_map_sg, dst_addr 21ee3dc000, nr_sgs 1, req->dst 000000004e2990d0, req->dlen 4096, sg_dma_len(sg) 4096 + [ 409.203239] idxd 0000:e7:02.0: iaa_decompress: desc->src1_addr 21ddd8b100, desc->src1_size 228, desc->dst_addr 21ee3dc000, desc->max_dst_size 4096, desc->src2_addr 0, desc->src2_size 0 + [ 409.203254] idxd 0000:e7:02.0: iaa_comp_adecompress: dma_map_sg, src_addr 21ddd8b100, nr_sgs 1, req->src 0000000084adab64, req->slen 228, sg_dma_len(sg) 228 + [ 409.203256] idxd 0000:e7:02.0: iaa_comp_adecompress: dma_map_sg, dst_addr 21f1551000, nr_sgs 1, req->dst 000000004e2990d0, req->dlen 4096, sg_dma_len(sg) 4096 + [ 409.203257] idxd 0000:e7:02.0: iaa_decompress: desc->src1_addr 21ddd8b100, desc->src1_size 228, desc->dst_addr 21f1551000, desc->max_dst_size 4096, desc->src2_addr 0, desc->src2_size 0 + +In order to unregister the iaa_crypto algorithm, and register a new +one using different parameters, any users of the current algorithm +should be stopped and the IAA workqueues and devices disabled. + +In the case of zswap, remove the iaa_crypto algorithm as the +compressor and turn off swap (to remove all references to +iaa_crypto):: + + echo lzo > /sys/module/zswap/parameters/compressor + swapoff -a + + echo 0 > /sys/module/zswap/parameters/accept_threshold_percent + echo 0 > /sys/module/zswap/parameters/max_pool_percent + echo 0 > /sys/module/zswap/parameters/enabled + +Once zswap is disabled and no longer using iaa_crypto, the IAA wqs and +devices can be disabled. + +The below script automatically does that:: + + #!/bin/bash + + echo "IAA devices:" + lspci -d:0cfe + echo "# IAA devices:" + lspci -d:0cfe | wc -l + + # + # count iaa instances + # + iaa_dev_id="0cfe" + num_iaa=$(lspci -d:${iaa_dev_id} | wc -l) + echo "Found ${num_iaa} IAA instances" + + # + # disable iaa wqs and devices + # + echo "Disable IAA" + + for ((i = 1; i < ${num_iaa} * 2; i += 2)); do + echo disable wq iax${i}/wq${i}.0 + accel-config disable-wq iax${i}/wq${i}.0 + echo disable iaa iax${i} + accel-config disable-device iax${i} + done + + echo "End Disable IAA" + +Finally, at this point the iaa_crypto module can be removed, which +will unregister the current iaa_crypto algorithm:: + + rmmod iaa_crypto + + +memory_madvise.c (gcc -o memory_memadvise memory_madvise.c):: + + #include + #include + #include + #include + #include + #include + + #ifndef MADV_PAGEOUT + #define MADV_PAGEOUT 21 /* force pages out immediately */ + #endif + + #define PG_SZ 4096 + + int main(int argc, char **argv) + { + int i, nr_pages = 1; + int64_t *dump_ptr; + char *addr, *a; + int loop = 1; + + if (argc > 1) + nr_pages = atoi(argv[1]); + + printf("Allocating %d pages to swap in/out\n", nr_pages); + + /* allocate pages */ + addr = mmap(NULL, nr_pages * PG_SZ, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); + *addr = 1; + + /* initialize data in page to all '*' chars */ + memset(addr, '*', nr_pages * PG_SZ); + + printf("Swapping out %d pages\n", nr_pages); + + /* Tell kernel to swap it out */ + madvise(addr, nr_pages * PG_SZ, MADV_PAGEOUT); + + while (loop > 0) { + /* Wait for swap out to finish */ + sleep(5); + + a = addr; + + printf("Swapping in %d pages\n", nr_pages); + + /* Access the page ... this will swap it back in again */ + for (i = 0; i < nr_pages; i++) { + if (a[0] != '*') { + printf("Bad data from decompress!!!!!\n"); + + dump_ptr = (int64_t *)a; + for (int j = 0; j < 100; j++) { + printf(" page %d data: %#llx\n", i, *dump_ptr); + dump_ptr++; + } + } + + a += PG_SZ; + } + + loop --; + } + + printf("Swapped out and in %d pages\n", nr_pages); diff --git a/Documentation/driver-api/crypto/iaa/index.rst b/Documentation/driver-api/crypto/iaa/index.rst new file mode 100644 index 000000000000..aa6837e27264 --- /dev/null +++ b/Documentation/driver-api/crypto/iaa/index.rst @@ -0,0 +1,20 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================= +IAA (Intel Analytics Accelerator) +================================= + +IAA provides hardware compression and decompression via the crypto +API. + +.. toctree:: + :maxdepth: 1 + + iaa-crypto + +.. only:: subproject and html + + Indices + ======= + + * :ref:`genindex` diff --git a/Documentation/driver-api/crypto/index.rst b/Documentation/driver-api/crypto/index.rst new file mode 100644 index 000000000000..fb9709b98bea --- /dev/null +++ b/Documentation/driver-api/crypto/index.rst @@ -0,0 +1,20 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============== +Crypto Drivers +============== + +Documentation for crypto drivers that may need more involved setup and +configuration. + +.. toctree:: + :maxdepth: 1 + + iaa/index + +.. only:: subproject and html + + Indices + ======= + + * :ref:`genindex` diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst index ff9aa1afdc62..2ad1237d5d5f 100644 --- a/Documentation/driver-api/index.rst +++ b/Documentation/driver-api/index.rst @@ -113,6 +113,7 @@ available subsections can be seen below. xillybus zorro hte/index + crypto/index .. only:: subproject and html