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* async_tx: fix kernel-doc notation warningsRandy Dunlap2023-03-242-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | Fix kernel-doc warnings by adding "struct" keyword or "enum" keyword. Also fix 2 function parameter descriptions. Change some functions and structs from kernel-doc /** notation to regular /* comment notation. async_pq.c:18: warning: cannot understand function prototype: 'struct page *pq_scribble_page; ' async_pq.c:18: error: Cannot parse struct or union! async_pq.c:40: warning: No description found for return value of 'do_async_gen_syndrome' async_pq.c:109: warning: Function parameter or member 'blocks' not described in 'do_sync_gen_syndrome' async_pq.c:109: warning: Function parameter or member 'offsets' not described in 'do_sync_gen_syndrome' async_pq.c:109: warning: Function parameter or member 'disks' not described in 'do_sync_gen_syndrome' async_pq.c:109: warning: Function parameter or member 'len' not described in 'do_sync_gen_syndrome' async_pq.c:109: warning: Function parameter or member 'submit' not described in 'do_sync_gen_syndrome' async_tx.c:136: warning: cannot understand function prototype: 'enum submit_disposition ' async_tx.c:264: warning: Function parameter or member 'tx' not described in 'async_tx_quiesce' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-crypto@vger.kernel.org Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* treewide: use get_random_bytes() when possibleJason A. Donenfeld2022-10-111-1/+1
| | | | | | | | | | | | | | The prandom_bytes() function has been a deprecated inline wrapper around get_random_bytes() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> # powerpc Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* crypto: add __init/__exit annotations to init/exit funcsXiu Jianfeng2022-09-241-2/+2
| | | | | | | Add missing __init/__exit annotations to init/exit funcs. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: cleanup commentsTom Rix2022-03-032-6/+6
| | | | | | | | | | | | | | | | | | | For spdx /* */ for *.h, // for *.c Space before spdx tag Replacements paramenters to parameters aymmetric to asymmetric sigature to signature boudary to boundary compliled to compiled eninges to engines explicity to explicitly Signed-off-by: Tom Rix <trix@redhat.com> Acked-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* async_xor: check src_offs is not NULL before updating itXiao Ni2021-06-101-1/+2
| | | | | | | | | | | | | | When PAGE_SIZE is greater than 4kB, multiple stripes may share the same page. Thus, src_offs is added to async_xor_offs() with array of offsets. However, async_xor() passes NULL src_offs to async_xor_offs(). In such case, src_offs should not be updated. Add a check before the update. Fixes: ceaf2966ab08(async_xor: increase src_offs when dropping destination page) Cc: stable@vger.kernel.org # v5.10+ Reported-by: Oleksandr Shchirskyi <oleksandr.shchirskyi@linux.intel.com> Tested-by: Oleksandr Shchirskyi <oleksandr.shchirskyi@intel.com> Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org>
* async_xor: increase src_offs when dropping destination pageXiao Ni2021-04-261-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | Now we support sharing one page if PAGE_SIZE is not equal stripe size. To support this, it needs to support calculating xor value with different offsets for each r5dev. One offset array is used to record those offsets. In RMW mode, parity page is used as a source page. It sets ASYNC_TX_XOR_DROP_DST before calculating xor value in ops_run_prexor5. So it needs to add src_list and src_offs at the same time. Now it only needs src_list. So the xor value which is calculated is wrong. It can cause data corruption problem. I can reproduce this problem 100% on a POWER8 machine. The steps are: mdadm -CR /dev/md0 -l5 -n3 /dev/sdb1 /dev/sdc1 /dev/sdd1 --size=3G mkfs.xfs /dev/md0 mount /dev/md0 /mnt/test mount: /mnt/test: mount(2) system call failed: Structure needs cleaning. Fixes: 29bcff787a25 ("md/raid5: add new xor function to support different page offset") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org>
* md/raid6: let async recovery function support different page offsetYufen Yu2020-09-242-45/+122
| | | | | | | | | | | For now, asynchronous raid6 recovery calculate functions are require common offset for pages. But, we expect them to support different page offset after introducing stripe shared page. Do that by simplily adding page offset where each page address are referred. Then, replace the old interface with the new ones in raid6 and raid6test. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
* md/raid6: let syndrome computor support different page offsetYufen Yu2020-09-242-32/+64
| | | | | | | | | | | | | | | For now, syndrome compute functions require common offset in the pages array. However, we expect them to support different offset when try to use shared page in the following. Simplily covert them by adding page offset where each page address are referred. Since the only caller of async_gen_syndrome() and async_syndrome_val() are in raid6, we don't want to reserve the old interface but modify the interface directly. After that, replacing old interfaces with new ones for raid6 and raid6test. Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
* md/raid5: add new xor function to support different page offsetYufen Yu2020-09-241-17/+103
| | | | | | | | | | | | | raid5 will call async_xor() and async_xor_val() to compute xor. For now, both of them require the common src/dst page offset. But, we want them to support different src/dst page offset for following shared page. Here, adding two new function async_xor_offs() and async_xor_val_offs() respectively for async_xor() and async_xor_val(). Signed-off-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Song Liu <songliubraving@fb.com>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335Thomas Gleixner2019-06-054-56/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 111 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.567572064@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102Thomas Gleixner2019-05-241-15/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 50 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091649.499889647@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 33Thomas Gleixner2019-05-241-17/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa the full gnu general public license is included in this distribution in the file called copying extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 7 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170857.277062491@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* async_pq: Remove VLA usageKyle Spiers2018-06-182-5/+9
| | | | | | | | | | | | | | In the quest to remove VLAs from the kernel[1], this adjusts the allocation of coefs and blocks to use the existing maximum values (with one new define, MAX_DISKS for coefs, and a reuse of the existing NDISKS for blocks). [1] https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Kyle Spiers <ksspiers@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
* License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman2017-11-022-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* async_tx: Fix DMA_PREP_FENCE usage in do_async_gen_syndrome()Anup Patel2017-05-161-3/+2
| | | | | | | | | | | | | | | | | | | | The DMA_PREP_FENCE is to be used when preparing Tx descriptor if output of Tx descriptor is to be used by next/dependent Tx descriptor. The DMA_PREP_FENSE will not be set correctly in do_async_gen_syndrome() when calling dma->device_prep_dma_pq() under following conditions: 1. ASYNC_TX_FENCE not set in submit->flags 2. DMA_PREP_FENCE not set in dma_flags 3. src_cnt (= (disks - 2)) is greater than dma_maxpq(dma, dma_flags) This patch fixes DMA_PREP_FENCE usage in do_async_gen_syndrome() taking inspiration from do_async_xor() implementation. Signed-off-by: Anup Patel <anup.patel@broadcom.com> Reviewed-by: Ray Jui <ray.jui@broadcom.com> Reviewed-by: Scott Branden <scott.branden@broadcom.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* async_pq_val: fix DMA memory leakJustin Maggard2016-10-051-4/+4
| | | | | | | | | | Add missing dmaengine_unmap_put(), so we don't OOM during RAID6 sync. Fixes: 1786b943dad0 ("async_pq_val: convert to dmaengine_unmap_data") Signed-off-by: Justin Maggard <jmaggard@netgear.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* mm/page_ref: add tracepoint to track down page reference manipulationJoonsoo Kim2016-03-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CMA allocation should be guaranteed to succeed by definition, but, unfortunately, it would be failed sometimes. It is hard to track down the problem, because it is related to page reference manipulation and we don't have any facility to analyze it. This patch adds tracepoints to track down page reference manipulation. With it, we can find exact reason of failure and can fix the problem. Following is an example of tracepoint output. (note: this example is stale version that printing flags as the number. Recent version will print it as human readable string.) <...>-9018 [004] 92.678375: page_ref_set: pfn=0x17ac9 flags=0x0 count=1 mapcount=0 mapping=(nil) mt=4 val=1 <...>-9018 [004] 92.678378: kernel_stack: => get_page_from_freelist (ffffffff81176659) => __alloc_pages_nodemask (ffffffff81176d22) => alloc_pages_vma (ffffffff811bf675) => handle_mm_fault (ffffffff8119e693) => __do_page_fault (ffffffff810631ea) => trace_do_page_fault (ffffffff81063543) => do_async_page_fault (ffffffff8105c40a) => async_page_fault (ffffffff817581d8) [snip] <...>-9018 [004] 92.678379: page_ref_mod: pfn=0x17ac9 flags=0x40048 count=2 mapcount=1 mapping=0xffff880015a78dc1 mt=4 val=1 [snip] ... ... <...>-9131 [001] 93.174468: test_pages_isolated: start_pfn=0x17800 end_pfn=0x17c00 fin_pfn=0x17ac9 ret=fail [snip] <...>-9018 [004] 93.174843: page_ref_mod_and_test: pfn=0x17ac9 flags=0x40068 count=0 mapcount=0 mapping=0xffff880015a78dc1 mt=4 val=-1 ret=1 => release_pages (ffffffff8117c9e4) => free_pages_and_swap_cache (ffffffff811b0697) => tlb_flush_mmu_free (ffffffff81199616) => tlb_finish_mmu (ffffffff8119a62c) => exit_mmap (ffffffff811a53f7) => mmput (ffffffff81073f47) => do_exit (ffffffff810794e9) => do_group_exit (ffffffff81079def) => SyS_exit_group (ffffffff81079e74) => entry_SYSCALL_64_fastpath (ffffffff817560b6) This output shows that problem comes from exit path. In exit path, to improve performance, pages are not freed immediately. They are gathered and processed by batch. During this process, migration cannot be possible and CMA allocation is failed. This problem is hard to find without this page reference tracepoint facility. Enabling this feature bloat kernel text 30 KB in my configuration. text data bss dec hex filename 12127327 2243616 1507328 15878271 f2487f vmlinux_disabled 12157208 2258880 1507328 15923416 f2f8d8 vmlinux_enabled Note that, due to header file dependency problem between mm.h and tracepoint.h, this feature has to open code the static key functions for tracepoints. Proposed by Steven Rostedt in following link. https://lkml.org/lkml/2015/12/9/699 [arnd@arndb.de: crypto/async_pq: use __free_page() instead of put_page()] [iamjoonsoo.kim@lge.com: fix build failure for xtensa] [akpm@linux-foundation.org: tweak Kconfig text, per Vlastimil] Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Michal Nazarewicz <mina86@mina86.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* async_tx: use GFP_NOWAIT rather than GFP_IONeilBrown2016-01-074-7/+7
| | | | | | | | | | | | | | | | | These async_XX functions are called from md/raid5 in an atomic section, between get_cpu() and put_cpu(), so they must not sleep. So use GFP_NOWAIT rather than GFP_IO. Dan Williams writes: Longer term async_tx needs to be merged into md directly as we can allocate this unmap data statically per-stripe rather than per request. Fixed: 7476bd79fc01 ("async_pq: convert to dmaengine_unmap_data") Cc: stable@vger.kernel.org (v3.13+) Reported-and-tested-by: Stanislav Samsonov <slava@annapurnalabs.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* md/raid5: activate raid6 rmw featureMarkus Stockhausen2015-04-221-3/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Glue it altogehter. The raid6 rmw path should work the same as the already existing raid5 logic. So emulate the prexor handling/flags and split functions as needed. 1) Enable xor_syndrome() in the async layer. 2) Split ops_run_prexor() into RAID4/5 and RAID6 logic. Xor the syndrome at the start of a rmw run as we did it before for the single parity. 3) Take care of rmw run in ops_run_reconstruct6(). Again process only the changed pages to get syndrome back into sync. 4) Enhance set_syndrome_sources() to fill NULL pages if we are in a rmw run. The lower layers will calculate start & end pages from that and call the xor_syndrome() correspondingly. 5) Adapt the several places where we ignored Q handling up to now. Performance numbers for a single E5630 system with a mix of 10 7200k desktop/server disks. 300 seconds random write with 8 threads onto a 3,2TB (10*400GB) RAID6 64K chunk without spare (group_thread_cnt=4) bsize rmw_level=1 rmw_level=0 rmw_level=1 rmw_level=0 skip_copy=1 skip_copy=1 skip_copy=0 skip_copy=0 4K 115 KB/s 141 KB/s 165 KB/s 140 KB/s 8K 225 KB/s 275 KB/s 324 KB/s 274 KB/s 16K 434 KB/s 536 KB/s 640 KB/s 534 KB/s 32K 751 KB/s 1,051 KB/s 1,234 KB/s 1,045 KB/s 64K 1,339 KB/s 1,958 KB/s 2,282 KB/s 1,962 KB/s 128K 2,673 KB/s 3,862 KB/s 4,113 KB/s 3,898 KB/s 256K 7,685 KB/s 7,539 KB/s 7,557 KB/s 7,638 KB/s 512K 19,556 KB/s 19,558 KB/s 19,652 KB/s 19,688 Kb/s Signed-off-by: Markus Stockhausen <stockhausen@collogia.de> Signed-off-by: NeilBrown <neilb@suse.de>
* dmaengine: fix xor sources continuationXuelin Shi2014-08-211-2/+1
| | | | | | | | | the partial xor result must be kept until the next tx is generated. Cc: <stable@vger.kernel.org> Signed-off-by: Xuelin Shi <xuelin.shi@freescale.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge commit 'dmaengine-3.13-v2' of ↵Vinod Koul2013-11-165-167/+238
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine Pull dmaengine changes from Dan 1/ Bartlomiej and Dan finalized a rework of the dma address unmap implementation. 2/ In the course of testing 1/ a collection of enhancements to dmatest fell out. Notably basic performance statistics, and fixed / enhanced test control through new module parameters 'run', 'wait', 'noverify', and 'verbose'. Thanks to Andriy and Linus for their review. 3/ Testing the raid related corner cases of 1/ triggered bugs in the recently added 16-source operation support in the ioatdma driver. 4/ Some minor fixes / cleanups to mv_xor and ioatdma. Conflicts: drivers/dma/dmatest.c Signed-off-by: Vinod Koul <vinod.koul@intel.com>
| * raid6test: add new corner case for ioatdma driverDan Williams2013-11-141-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | With 24 disks and an ioatdma instance with 16 source support there is a corner case where the driver needs to be careful to account for the number of implied sources in the continuation case. Also bump the default case to test more than 16 sources now that it triggers different paths in offload drivers. Cc: Dave Jiang <dave.jiang@intel.com> Acked-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * dmaengine: remove DMA unmap flagsBartlomiej Zolnierkiewicz2013-11-144-13/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove no longer needed DMA unmap flags: - DMA_COMPL_SKIP_SRC_UNMAP - DMA_COMPL_SKIP_DEST_UNMAP - DMA_COMPL_SRC_UNMAP_SINGLE - DMA_COMPL_DEST_UNMAP_SINGLE Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Acked-by: Jon Mason <jon.mason@intel.com> Acked-by: Mark Brown <broonie@linaro.org> [djbw: clean up straggling skip unmap flags in ntb] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_pq_val: convert to dmaengine_unmap_dataDan Williams2013-11-141-23/+35
| | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_pq: convert to dmaengine_unmap_dataDan Williams2013-11-141-52/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> [bzolnier: keep temporary dma_dest array in do_async_gen_syndrome()] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_raid6_recov: convert to dmaengine_unmap_dataDan Williams2013-11-141-20/+49
| | | | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> [bzolnier: keep temporary dma_dest array in async_mult()] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_xor_val: convert to dmaengine_unmap_dataDan Williams2013-11-141-13/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> [bzolnier: minor cleanups] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_xor: convert to dmaengine_unmap_dataDan Williams2013-11-141-44/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Later we can push this unmap object up to the raid layer and get rid of the 'scribble' parameter. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> [bzolnier: minor cleanups] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_memcpy: convert to dmaengine_unmap_dataDan Williams2013-11-141-17/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the generic unmap object to unmap dma buffers. Cc: Vinod Koul <vinod.koul@intel.com> Cc: Tomasz Figa <t.figa@samsung.com> Cc: Dave Jiang <dave.jiang@intel.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> [bzolnier: add missing unmap->len initialization] [bzolnier: fix whitespace damage] Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> [djbw: add DMA_ENGINE=n support] Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | async_tx: use DMA_COMPLETE for dma completion statusVinod Koul2013-10-251-2/+2
|/ | | | | | Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
* drivers/dma: remove unused support for MEMSET operationsBartlomiej Zolnierkiewicz2013-07-033-94/+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>
* raid6test: use prandom_bytes()Akinobu Mita2013-04-291-7/+2
| | | | | | | | | | Use prandom_bytes() to generate random bytes for test data. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Dan Williams <djbw@fb.com> Cc: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* async_tx: fix checking of dma_wait_for_async_tx() return valueBartlomiej Zolnierkiewicz2013-01-071-4/+5
| | | | | | | | | | | | dma_wait_for_async_tx() can also return DMA_PAUSED (which should be considered as error). Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <djbw@fb.com> Cc: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <djbw@fb.com>
* async_tx: fix build for async_memsetBartlomiej Zolnierkiewicz2013-01-071-0/+1
| | | | | | | | | | Add missing <linux/module.h> include. Cc: Dan Williams <djbw@fb.com> Cc: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <djbw@fb.com>
* async_tx: add missing DMA unmap to async_memcpy()Bartlomiej Zolnierkiewicz2013-01-071-0/+6
| | | | | | | | | | Do DMA unmap on ->device_prep_dma_memcpy failure. Cc: Dan Williams <djbw@fb.com> Cc: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Dan Williams <djbw@fb.com>
* async_tx: use memchr_invAkinobu Mita2013-01-071-3/+1
| | | | | | | | | Use memchr_inv() to check the specified page is filled with zero. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <djbw@fb.com> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
* crypto: remove the second argument of k[un]map_atomic()Cong Wang2012-03-201-4/+4
| | | | Signed-off-by: Cong Wang <amwang@redhat.com>
* crypto: add module.h to those files that are explicitly using itPaul Gortmaker2011-10-316-0/+6
| | | | | | | | Part of the include cleanups means that the implicit inclusion of module.h via device.h is going away. So fix things up in advance. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* net: remove mm.h inclusion from netdevice.hAlexey Dobriyan2011-06-211-0/+1
| | | | | | | | | | | | | | | | | Remove linux/mm.h inclusion from netdevice.h -- it's unused (I've checked manually). To prevent mm.h inclusion via other channels also extract "enum dma_data_direction" definition into separate header. This tiny piece is what gluing netdevice.h with mm.h via "netdevice.h => dmaengine.h => dma-mapping.h => scatterlist.h => mm.h". Removal of mm.h from scatterlist.h was tried and was found not feasible on most archs, so the link was cutoff earlier. Hope people are OK with tiny include file. Note, that mm_types.h is still dragged in, but it is a separate story. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Merge branch 'next' of ↵Linus Torvalds2010-10-271-13/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (48 commits) DMAENGINE: move COH901318 to arch_initcall dma: imx-dma: fix signedness bug dma/timberdale: simplify conditional ste_dma40: remove channel_type ste_dma40: remove enum for endianess ste_dma40: remove TIM_FOR_LINK option ste_dma40: move mode_opt to separate config ste_dma40: move channel mode to a separate field ste_dma40: move priority to separate field ste_dma40: add variable to indicate valid dma_cfg async_tx: make async_tx channel switching opt-in move async raid6 test to lib/Kconfig.debug dmaengine: Add Freescale i.MX1/21/27 DMA driver intel_mid_dma: change the slave interface intel_mid_dma: fix the WARN_ONs intel_mid_dma: Add sg list support to DMA driver intel_mid_dma: Allow DMAC2 to share interrupt intel_mid_dma: Allow IRQ sharing intel_mid_dma: Add runtime PM support DMAENGINE: define a dummy filter function for ste_dma40 ...
| * move async raid6 test to lib/Kconfig.debugDan Williams2010-10-071-13/+0
| | | | | | | | | | | | | | | | | | | | | | The prompt for "Self test for hardware accelerated raid6 recovery" does not belong in the top level configuration menu. All the options in crypto/async_tx/Kconfig are selected and do not depend on CRYPTO. Kconfig.debug seems like a reasonable fit. Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | mm: strictly nested kmap_atomic()Peter Zijlstra2010-10-261-1/+1
|/ | | | | | | | | | | | | | | | | | | | | Ensure kmap_atomic() usage is strictly nested Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Miller <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'async' of macbook:git/btrfs-unstableDavid Woodhouse2010-08-091-0/+14
|\ | | | | | | | | | | Conflicts: drivers/md/Makefile lib/raid6/unroll.pl
| * async_tx: Move ASYNC_RAID6_TEST option to crypto/async_tx/, fix dependenciesDavid Woodhouse2009-10-291-0/+14
| | | | | | | | Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* | Merge branch 'next' of ↵Linus Torvalds2010-05-211-27/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: DMAENGINE: extend the control command to include an arg async_tx: trim dma_async_tx_descriptor in 'no channel switch' case DMAENGINE: DMA40 fix for allocation of logical channel 0 DMAENGINE: DMA40 support paused channel status dmaengine: mpc512x: Use resource_size DMA ENGINE: Do not reset 'private' of channel ioat: Remove duplicated devm_kzalloc() calls for ioatdma_device ioat3: disable cacheline-unaligned transfers for raid operations ioat2,3: convert to producer/consumer locking ioat: convert to circ_buf DMAENGINE: Support for ST-Ericssons DMA40 block v3 async_tx: use of kzalloc/kfree requires the include of slab.h dmaengine: provide helper for setting txstate DMAENGINE: generic channel status v2 DMAENGINE: generic slave control v2 dma: timb-dma: Update comment and fix compiler warning dma: Add timb-dma DMAENGINE: COH 901 318 fix bytesleft DMAENGINE: COH 901 318 rename confusing vars
| * | async_tx: trim dma_async_tx_descriptor in 'no channel switch' caseDan Williams2010-05-171-27/+19
| | | | | | | | | | | | | | | | | | | | | Saves 24 bytes per descriptor (64-bit) when the channel-switching capabilities of async_tx are not required. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | | raid6: fix recovery performance regressionDan Williams2010-05-051-8/+13
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The raid6 recovery code should immediately drop back to the optimized synchronous path when a p+q dma resource is not available. Otherwise we run the non-optimized/multi-pass async code in sync mode. Verified with raid6test (NDISKS=255) Applies to kernels >= 2.6.32. Cc: <stable@kernel.org> Acked-by: NeilBrown <neilb@suse.de> Reported-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-302-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* | async_tx: expand async raid6 test to cover ioatdma corner caseDan Williams2009-12-171-0/+7
| | | | | | | | | | | | | | Add explicit 11 and 12 disks cases to exercise the 0 < src_cnt % 8 < 3 corner case in the ioatdma driver. Signed-off-by: Dan Williams <dan.j.williams@intel.com>