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path: root/drivers/s390/cio/vfio_ccw_cp.c (follow)
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2019-04-24vfio-ccw: make it safe to access channel programsCornelia Huck1-1/+20
When we get a solicited interrupt, the start function may have been cleared by a csch, but we still have a channel program structure allocated. Make it safe to call the cp accessors in any case, so we can call them unconditionally. While at it, also make sure that functions called from other parts of the code return gracefully if the channel program structure has not been initialized (even though that is a bug in the caller). Reviewed-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-02-26s390/cio: Use cpa range elsewhere within vfio-ccwEric Farman1-12/+6
Since we have a little function to see whether a channel program address falls within a range of CCWs, let's use it in the other places of code that make these checks. (Why isn't ccw_head fully removed? Well, because this way some longs lines don't have to be reflowed.) Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20190222183941.29596-3-farman@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-02-26s390/cio: Fix vfio-ccw handling of recursive TICsEric Farman1-1/+36
The routine ccwchain_calc_length() is tasked with looking at a channel program, seeing how many CCWs are chained together by the presence of the Chain-Command flag, and returning a count to the caller. Previously, it also considered a Transfer-in-Channel CCW as being an appropriate mechanism for chaining. The problem at the time was that the TIC CCW will almost certainly not go to the next CCW in memory (because the CC flag would be sufficient), and so advancing to the next 8 bytes will cause us to read potentially invalid memory. So that comparison was removed, and the target of the TIC is processed as a new chain. This is fine when a TIC goes to a new chain (consider a NOP+TIC to a channel program that is being redriven), but there is another scenario where this falls apart. A TIC can be used to "rewind" a channel program, for example to find a particular record on a disk with various orientation CCWs. In this case, we DO want to consider the memory after the TIC since the TIC will be skipped once the requested criteria is met. This is due to the Status Modifier presented by the device, though software doesn't need to operate on it beyond understanding the behavior change of how the channel program is executed. So to handle this, we will re-introduce the check for a TIC CCW but limit it by examining the target of the TIC. If the TIC doesn't go back into the current chain, then current behavior applies; we should stop counting CCWs and let the target of the TIC be handled as a new chain. But, if the TIC DOES go back into the current chain, then we need to keep looking at the memory after the TIC for when the channel breaks out of the TIC loop. We can't use tic_target_chain_exists() because the chain in question hasn't been built yet, so we will redefine that comparison with some small functions to make it more readable and to permit refactoring later. Fixes: 405d566f98ae ("vfio-ccw: Don't assume there are more ccws after a TIC") Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20190222183941.29596-2-farman@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-02-04vfio-ccw: Don't assume there are more ccws after a TICFarhan Ali1-1/+1
When trying to calculate the length of a ccw chain, we assume there are ccws after a TIC. This can lead to overcounting and copying garbage data from guest memory. Signed-off-by: Farhan Ali <alifm@linux.ibm.com> Message-Id: <d63748c1f1b03147bcbf401596638627a5e35ef7.1548082107.git.alifm@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-11-13s390/cio: Fix cleanup when unsupported IDA format is usedEric Farman1-1/+3
Direct returns from within a loop are rude, but it doesn't mean it gets to avoid releasing the memory acquired beforehand. Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20181109023937.96105-3-farman@linux.ibm.com> Reviewed-by: Farhan Ali <alifm@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Acked-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-11-13s390/cio: Fix cleanup of pfn_array alloc failureEric Farman1-1/+1
If pfn_array_alloc fails somehow, we need to release the pfn_array_table that was malloc'd earlier. Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20181109023937.96105-2-farman@linux.ibm.com> Acked-by: Halil Pasic <pasic@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-10-02s390/cio: Fix how vfio-ccw checks pinned pagesEric Farman1-1/+1
We have two nested loops to check the entries within the pfn_array_table arrays. But we mistakenly use the outer array as an index in our check, and completely ignore the indexing performed by the inner loop. Cc: stable@vger.kernel.org Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20181002010235.42483-1-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-05-29vfio: ccw: set ccw->cda to NULL defensivelyDong Jia Shi1-11/+20
Let's avoid free on ccw->cda that points to a guest address or an already freed memory area by setting it to NULL if memory allocation didn't happen or failed. Signed-off-by: Dong Jia Shi <bjsdjshi@linux.ibm.com> Message-Id: <20180523025645.8978-4-bjsdjshi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-05-29vfio: ccw: refactor and improve pfn_array_alloc_pin()Dong Jia Shi1-46/+36
This refactors pfn_array_alloc_pin() and also improves it by adding defensive code in error handling so that calling pfn_array_unpin_free() after error return won't lead to problem. This mainly does: 1. Merge pfn_array_pin() into pfn_array_alloc_pin(), since there is no other user of pfn_array_pin(). As a result, also remove kernel-doc for pfn_array_pin() and add/update kernel-doc for pfn_array_alloc_pin() and struct pfn_array. 2. For a vfio_pin_pages() failure, set pa->pa_nr to zero to indicate zero pages were pinned. 3. Set pa->pa_iova_pfn to NULL right after it was freed. Suggested-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.ibm.com> Message-Id: <20180523025645.8978-3-bjsdjshi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-05-29vfio: ccw: shorten kernel doc description for pfn_array_pin()Dong Jia Shi1-8/+6
The kernel doc description for usage of the struct pfn_array in pfn_array_pin() is unnecessary long. Let's shorten it by describing the contents of the struct pfn_array fields at the struct's definition instead. Suggested-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.ibm.com> Message-Id: <20180523025645.8978-2-bjsdjshi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-05-29vfio: ccw: push down unsupported IDA checkHalil Pasic1-3/+16
There is at least one relevant guest OS that doesn't set the IDA flags in the ORB as we would like them, but never uses any IDA. So instead of saying -EOPNOTSUPP when observing an ORB, such that a channel program specified by it could be a not supported one, let us say -EOPNOTSUPP only if the channel program is a not supported one. Of course, the real solution would be doing proper translation for all IDA. This is possible, but given the current code not straight forward. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Tested-by: Jason J. Herne <jjherne@linux.ibm.com> Message-Id: <20180516173342.15174-1-pasic@linux.ibm.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2018-04-27vfio: ccw: fix cleanup if cp_prefetch failsHalil Pasic1-1/+12
If the translation of a channel program fails, we may end up attempting to clean up (free, unpin) stuff that never got translated (and allocated, pinned) in the first place. By adjusting the lengths of the chains accordingly (so the element that failed, and all subsequent elements are excluded) cleanup activities based on false assumptions can be avoided. Let's make sure cp_free works properly after cp_prefetch returns with an error by setting ch_len of a ccw chain to the number of the translated CCWs on that chain. Cc: stable@vger.kernel.org #v4.12+ Acked-by: Pierre Morel <pmorel@linux.vnet.ibm.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20180423110113.59385-2-bjsdjshi@linux.vnet.ibm.com> [CH: fixed typos] Signed-off-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-05s390/cio: fix kernel-doc usageSebastian Ott1-1/+1
Fix the kernel-doc usage in cio to get rid of (W=1) build warnings like: drivers/s390/cio/cio.c:1068: warning: No description found for parameter 'sch' Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-11-13Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds1-5/+19
Pull s390 updates from Heiko Carstens: "Since Martin is on vacation you get the s390 pull request for the v4.15 merge window this time from me. Besides a lot of cleanups and bug fixes these are the most important changes: - a new regset for runtime instrumentation registers - hardware accelerated AES-GCM support for the aes_s390 module - support for the new CEX6S crypto cards - support for FORTIFY_SOURCE - addition of missing z13 and new z14 instructions to the in-kernel disassembler - generate opcode tables for the in-kernel disassembler out of a simple text file instead of having to manually maintain those tables - fast memset16, memset32 and memset64 implementations - removal of named saved segment support - hardware counter support for z14 - queued spinlocks and queued rwlocks implementations for s390 - use the stack_depth tracking feature for s390 BPF JIT - a new s390_sthyi system call which emulates the sthyi (store hypervisor information) instruction - removal of the old KVM virtio transport - an s390 specific CPU alternatives implementation which is used in the new spinlock code" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits) MAINTAINERS: add virtio-ccw.h to virtio/s390 section s390/noexec: execute kexec datamover without DAT s390: fix transactional execution control register handling s390/bpf: take advantage of stack_depth tracking s390: simplify transactional execution elf hwcap handling s390/zcrypt: Rework struct ap_qact_ap_info. s390/virtio: remove unused header file kvm_virtio.h s390: avoid undefined behaviour s390/disassembler: generate opcode tables from text file s390/disassembler: remove insn_to_mnemonic() s390/dasd: avoid calling do_gettimeofday() s390: vfio-ccw: Do not attempt to free no-op, test and tic cda. s390: remove named saved segment support s390/archrandom: Reconsider s390 arch random implementation s390/pci: do not require AIS facility s390/qdio: sanitize put_indicator s390/qdio: use atomic_cmpxchg s390/nmi: avoid using long-displacement facility s390: pass endianness info to sparse s390/decompressor: remove informational messages ...
2017-11-08s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.Jason J. Herne1-0/+2
Because we do not make use of the cda (channel data address) for test, no-op ccws no address translation takes place. This means cda could contain a guest address which we do not want to attempt to free. Let's check the command type and skip cda free when it is not needed. For a TIC ccw, ccw->cda points to either a ccw in an existing chain or it points to a whole new allocated chain. In either case the data will be freed when the owning chain is freed. Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com> Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com> Message-Id: <1510068152-21988-1-git-send-email-jjherne@linux.vnet.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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>
2017-10-16vfio: ccw: validate the count field of a ccw before pinningDong Jia Shi1-1/+17
If the count field of a ccw is zero, there is no need to try to pin page(s) for it. Let's check the count value before starting pinning operations. Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20171011023822.42948-3-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-10-16vfio: ccw: bypass bad idaw address when fetching IDAL ccwsDong Jia Shi1-4/+0
We currently return the same error code (-EFAULT) to indicate two different error cases: 1. a bug in vfio-ccw implementation has been found. 2. a buggy channel program has been detected. This brings difficulty for userland program (specifically Qemu) to handle. Let's use -EFAULT to only indicate the first case. For the second case, we simply hand over the ccws to lower level for further handling. Notice: Once a bad idaw address is detected, the current behavior is to suppress the ssch. With this fix, the channel program will be accepted, and part of the channel program (the part ahead of the bad idaw) could possibly be executed by the device before I/O conclusion. Suggested-by: Halil Pasic <pasic@linux.vnet.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20171011023822.42948-2-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-07-24vfio: ccw: fix bad ptr math for TIC cda translationJason J. Herne1-1/+1
When we are translating channel data addresses from guest to host address space for TIC instructions we are getting incorrect addresses because of a pointer arithmetic error. We currently calculate the offset of the TIC's cda from the start of the channel program chain (ccw->cda - ccw_head). We then add that to the address of the ccw chain in host memory (iter->ch_ccw). The problem is that iter->ch_ccw is a pointer to struct ccw1 so when we increment it we are actually incrementing by the size of struct ccw1 which is 8 bytes. The intent was to increment by n-bytes, not n*8. The fix: cast iter->ch_ccw to char* so it will be incremented by n*1. Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com> Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20170721011436.76112-1-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2017-03-31vfio: ccw: introduce support for ccw0Dong Jia Shi1-3/+29
Although Linux does not use format-0 channel command words (CCW0) these are a non-optional part of the platform spec, and for the sake of platform compliance, and possibly some non-Linux guests, we have to support CCW0. Making the kernel execute a format 0 channel program is too much hassle because we would need to allocate and use memory which can be addressed by 24 bit physical addresses (because of CCW0.cda). So we implement CCW0 support by translating the channel program into an equivalent CCW1 program instead. Based upon an orginal patch by Kai Yue Wang. Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20170317031743.40128-16-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-03-31vfio: ccw: introduce channel program interfacesDong Jia Shi1-0/+816
Introduce ccwchain structure and helper functions that can be used to handle a channel program issued from a virtual machine. The following limitations apply: 1. Supports only prefetch enabled mode. 2. Supports idal(c64) ccw chaining. 3. Supports 4k idaw. 4. Supports ccw1. 5. Supports direct ccw chaining by translating them to idal ccws. CCW translation requires to leverage the vfio_(un)pin_pages interfaces to pin/unpin sets of mem pages frequently. Currently we have a lack of support to do this in an efficient way. So we introduce pfn_array data structure and helper functions to handle pin/unpin operations here. Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Message-Id: <20170317031743.40128-6-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>