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path: root/drivers/vhost/vhost.h
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2021-07-03vhost: fix up vhost_work coding styleMike Christie
Switch from a mix of tabs and spaces to just tabs. Signed-off-by: Mike Christie <michael.christie@oracle.com> Link: https://lore.kernel.org/r/20210525174733.6212-6-michael.christie@oracle.com Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-07-03vhost: fix poll coding styleMike Christie
We use 3 coding styles in this struct. Switch to just tabs. Signed-off-by: Mike Christie <michael.christie@oracle.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210525174733.6212-5-michael.christie@oracle.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-07-03vhost: remove work arg from vhost_work_flushMike Christie
vhost_work_flush doesn't do anything with the work arg. This patch drops it and then renames vhost_work_flush to vhost_work_dev_flush to reflect that the function flushes all the works in the dev and not just a specific queue or work item. Signed-off-by: Mike Christie <michael.christie@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Link: https://lore.kernel.org/r/20210525174733.6212-2-michael.christie@oracle.com Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-07-03vhost: Remove the repeated declarationShaokun Zhang
Function 'vhost_vring_ioctl' is declared twice, remove the repeated declaration. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Link: https://lore.kernel.org/r/1621857884-19964-1-git-send-email-zhangshaokun@hisilicon.com Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-11-15vhost: add helper to check if a vq has been setupMike Christie
This adds a helper check if a vq has been setup. The next patches will use this when we move the vhost scsi cmd preallocation from per session to per vq. In the per vq case, we only want to allocate cmds for vqs that have actually been setup and not for all the possible vqs. Signed-off-by: Mike Christie <michael.christie@oracle.com> Link: https://lore.kernel.org/r/1604986403-4931-2-git-send-email-michael.christie@oracle.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-10-21vhost_vdpa: remove unnecessary spin_lock in vhost_vring_callZhu Lingshan
This commit removed unnecessary spin_locks in vhost_vring_call and related operations. Because we manipulate irq offloading contents in vhost_vdpa ioctl code path which is already protected by dev mutex and vq mutex. Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com> Link: https://lore.kernel.org/r/20200909065234.3313-1-lingshan.zhu@intel.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-10-21vhost: reduce stack usage in log_usedLi Wang
Fix the warning: [-Werror=-Wframe-larger-than=] drivers/vhost/vhost.c: In function log_used: drivers/vhost/vhost.c:1906:1: warning: the frame size of 1040 bytes is larger than 1024 bytes Signed-off-by: Li Wang <li.wang@windriver.com> Link: https://lore.kernel.org/r/1600106889-25013-1-git-send-email-li.wang@windriver.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-08-05vhost: generialize backend features setting/gettingJason Wang
Move the backend features setting/getting from net.c to vhost.c to be reused by vhost-vdpa. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200804162048.22587-3-eli@mellanox.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-08-05vhost: introduce vhost_vring_callZhu Lingshan
This commit introduces struct vhost_vring_call which replaced raw struct eventfd_ctx *call_ctx in struct vhost_virtqueue. Besides eventfd_ctx, it contains a spin lock and an irq_bypass_producer in its structure. Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com> Suggested-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200731065533.4144-2-lingshan.zhu@intel.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-04vhost: allow device that does not depend on vhost workerJason Wang
vDPA device currently relays the eventfd via vhost worker. This is inefficient due the latency of wakeup and scheduling, so this patch tries to introduce a use_worker attribute for the vhost device. When use_worker is not set with vhost_dev_init(), vhost won't try to allocate a worker thread and the vhost_poll will be processed directly in the wakeup function. This help for vDPA since it reduces the latency caused by vhost worker. In my testing, it saves 0.2 ms in pings between VMs on a mutual host. Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200529080303.15449-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-06-02virtio: force spec specified alignment on typesMichael S. Tsirkin
The ring element addresses are passed between components with different alignments assumptions. Thus, if guest/userspace selects a pointer and host then gets and dereferences it, we might need to decrease the compiler-selected alignment to prevent compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration, but it seems safer to handle this generally. Note that userspace that allocates the memory is actually OK and does not need to be fixed, but userspace that gets it from guest or another process does need to be fixed. The later doesn't generally talk to the kernel so while it might be buggy it's not talking to the kernel in the buggy way - it's just using the header in the buggy way - so fixing header and asking userspace to recompile is the best we can do. I verified that the produced kernel binary on x86 is exactly identical before and after the change. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-16vhost: Create accessors for virtqueues private_dataEugenio Pérez
Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Link: https://lore.kernel.org/r/20200331192804.6019-2-eperezma@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01vhost: factor out IOTLBJason Wang
This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01vhost: allow per device message handlerJason Wang
This patch allow device to register its own message handler during vhost_dev_init(). vDPA device will use it to implement its own DMA mapping logic. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-3-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-12-04vhost, kcov: collect coverage from vhost_workerAndrey Konovalov
Add kcov_remote_start()/kcov_remote_stop() annotations to the vhost_worker() function, which is responsible for processing vhost works. Since vhost_worker() threads are spawned per vhost device instance the common kcov handle is used for kcov_remote_start()/stop() annotations (see Documentation/dev-tools/kcov.rst for details). As the result kcov can now be used to collect coverage from vhost worker threads. Link: http://lkml.kernel.org/r/e49d5d154e5da6c9ada521d2b7ce10a49ce9f98b.1572366574.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Alexander Potapenko <glider@google.com> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Windsor <dwindsor@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Wang <jasowang@redhat.com> Cc: Marco Elver <elver@google.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-04Revert "vhost: access vq metadata through kernel virtual address"Michael S. Tsirkin
This reverts commit 7f466032dc ("vhost: access vq metadata through kernel virtual address"). The commit caused a bunch of issues, and while commit 73f628ec9e ("vhost: disable metadata prefetch optimization") disabled the optimization it's not nice to keep lots of dead code around. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-26vhost: disable metadata prefetch optimizationMichael S. Tsirkin
This seems to cause guest and host memory corruption. Disable for now until we get a better handle on that. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06vhost: fix clang build warningMichael S. Tsirkin
Clang warns: drivers/vhost/vhost.c:2085:5: warning: macro expansion producing 'defined' has undefined behavior [-Wexpansion-to-defined] #if VHOST_ARCH_CAN_ACCEL_UACCESS ^ drivers/vhost/vhost.h:98:38: note: expanded from macro 'VHOST_ARCH_CAN_ACCEL_UACCESS' #define VHOST_ARCH_CAN_ACCEL_UACCESS defined(CONFIG_MMU_NOTIFIER) && \ ^ It's being pedantic for the sake of portability, but the fix is easy enough. Rework the definition of VHOST_ARCH_CAN_ACCEL_UACCESS to expand to a constant. Fixes: 7f466032dc9e ("vhost: access vq metadata through kernel virtual address") Link: https://github.com/ClangBuiltLinux/linux/issues/508 Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2019-06-05vhost: access vq metadata through kernel virtual addressJason Wang
It was noticed that the copy_to/from_user() friends that was used to access virtqueue metdata tends to be very expensive for dataplane implementation like vhost since it involves lots of software checks, speculation barriers, hardware feature toggling (e.g SMAP). The extra cost will be more obvious when transferring small packets since the time spent on metadata accessing become more significant. This patch tries to eliminate those overheads by accessing them through direct mapping of those pages. Invalidation callbacks is implemented for co-operation with general VM management (swap, KSM, THP or NUMA balancing). We will try to get the direct mapping of vq metadata before each round of packet processing if it doesn't exist. If we fail, we will simplely fallback to copy_to/from_user() friends. This invalidation and direct mapping access are synchronized through spinlock and RCU. All matedata accessing through direct map is protected by RCU, and the setup or invalidation are done under spinlock. This method might does not work for high mem page which requires temporary mapping so we just fallback to normal copy_to/from_user() and may not for arch that has virtual tagged cache since extra cache flushing is needed to eliminate the alias. This will result complex logic and bad performance. For those archs, this patch simply go for copy_to/from_user() friends. This is done by ruling out kernel mapping codes through ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE. Note that this is only done when device IOTLB is not enabled. We could use similar method to optimize IOTLB in the future. Tests shows at most about 23% improvement on TX PPS when using virtio-user + vhost_net + xdp1 + TAP on 2.6GHz Broadwell: SMAP on | SMAP off Before: 5.2Mpps | 7.1Mpps After: 6.4Mpps | 8.2Mpps Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: James Bottomley <James.Bottomley@hansenpartnership.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Jerome Glisse <jglisse@redhat.com> Cc: linux-mm@kvack.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-parisc@vger.kernel.org Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()Jason Wang
Rename the function to be more accurate since it actually tries to prefetch vq metadata address in IOTLB. And this will be used by following patch to prefetch metadata virtual addresses. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-27vhost: introduce vhost_exceeds_weight()Jason Wang
We used to have vhost_exceeds_weight() for vhost-net to: - prevent vhost kthread from hogging the cpu - balance the time spent between TX and RX This function could be useful for vsock and scsi as well. So move it to vhost.c. Device must specify a weight which counts the number of requests, or it can also specific a byte_weight which counts the number of bytes that has been processed. Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-01-28vhost: fix OOB in get_rx_bufs()Jason Wang
After batched used ring updating was introduced in commit e2b3b35eb989 ("vhost_net: batch used ring update in rx"). We tend to batch heads in vq->heads for more than one packet. But the quota passed to get_rx_bufs() was not correctly limited, which can result a OOB write in vq->heads. headcount = get_rx_bufs(vq, vq->heads + nvq->done_idx, vhost_len, &in, vq_log, &log, likely(mergeable) ? UIO_MAXIOV : 1); UIO_MAXIOV was still used which is wrong since we could have batched used in vq->heads, this will cause OOB if the next buffer needs more than 960 (1024 (UIO_MAXIOV) - 64 (VHOST_NET_BATCH)) heads after we've batched 64 (VHOST_NET_BATCH) heads: Acked-by: Stefan Hajnoczi <stefanha@redhat.com> ============================================================================= BUG kmalloc-8k (Tainted: G B ): Redzone overwritten ----------------------------------------------------------------------------- INFO: 0x00000000fd93b7a2-0x00000000f0713384. First byte 0xa9 instead of 0xcc INFO: Allocated in alloc_pd+0x22/0x60 age=3933677 cpu=2 pid=2674 kmem_cache_alloc_trace+0xbb/0x140 alloc_pd+0x22/0x60 gen8_ppgtt_create+0x11d/0x5f0 i915_ppgtt_create+0x16/0x80 i915_gem_create_context+0x248/0x390 i915_gem_context_create_ioctl+0x4b/0xe0 drm_ioctl_kernel+0xa5/0xf0 drm_ioctl+0x2ed/0x3a0 do_vfs_ioctl+0x9f/0x620 ksys_ioctl+0x6b/0x80 __x64_sys_ioctl+0x11/0x20 do_syscall_64+0x43/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 INFO: Slab 0x00000000d13e87af objects=3 used=3 fp=0x (null) flags=0x200000000010201 INFO: Object 0x0000000003278802 @offset=17064 fp=0x00000000e2e6652b Fixing this by allocating UIO_MAXIOV + VHOST_NET_BATCH iovs for vhost-net. This is done through set the limitation through vhost_dev_init(), then set_owner can allocate the number of iov in a per device manner. This fixes CVE-2018-16880. Fixes: e2b3b35eb989 ("vhost_net: batch used ring update in rx") Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17vhost: log dirty page correctlyJason Wang
Vhost dirty page logging API is designed to sync through GPA. But we try to log GIOVA when device IOTLB is enabled. This is wrong and may lead to missing data after migration. To solve this issue, when logging with device IOTLB enabled, we will: 1) reuse the device IOTLB translation result of GIOVA->HVA mapping to get HVA, for writable descriptor, get HVA through iovec. For used ring update, translate its GIOVA to HVA 2) traverse the GPA->HVA mapping to get the possible GPA and log through GPA. Pay attention this reverse mapping is not guaranteed to be unique, so we should log each possible GPA in this case. This fix the failure of scp to guest during migration. In -next, we will probably support passing GIOVA->GPA instead of GIOVA->HVA. Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API") Reported-by: Jintack Lim <jintack@cs.columbia.edu> Cc: Jintack Lim <jintack@cs.columbia.edu> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-06vhost: switch to use new message formatJason Wang
We use to have message like: struct vhost_msg { int type; union { struct vhost_iotlb_msg iotlb; __u8 padding[64]; }; }; Unfortunately, there will be a hole of 32bit in 64bit machine because of the alignment. This leads a different formats between 32bit API and 64bit API. What's more it will break 32bit program running on 64bit machine. So fixing this by introducing a new message type with an explicit 32bit reserved field after type like: struct vhost_msg_v2 { __u32 type; __u32 reserved; union { struct vhost_iotlb_msg iotlb; __u8 padding[64]; }; }; We will have a consistent ABI after switching to use this. To enable this capability, introduce a new ioctl (VHOST_SET_BAKCEND_FEATURE) for userspace to enable this feature (VHOST_BACKEND_F_IOTLB_V2). Fixes: 6b1e6cc7855b ("vhost: new device IOTLB API") Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-11vhost: return bool from *_access_ok() functionsStefan Hajnoczi
Currently vhost *_access_ok() functions return int. This is error-prone because there are two popular conventions: 1. 0 means failure, 1 means success 2. -errno means failure, 0 means success Although vhost mostly uses #1, it does not do so consistently. umem_access_ok() uses #2. This patch changes the return type from int to bool so that false means failure and true means success. This eliminates a potential source of errors. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-20vhost: fix vhost ioctl signature to build with clangSonny Rao
Clang is particularly anal about signed vs unsigned comparisons and doesn't like the fact that some ioctl numbers set the MSB, so we get this error when trying to build vhost on aarch64: drivers/vhost/vhost.c:1400:7: error: overflow converting case value to switch condition type (3221794578 to 18446744072636378898) [-Werror, -Wswitch] case VHOST_GET_VRING_BASE: 3221794578 is 0xC008AF12 in hex 18446744072636378898 is 0xFFFFFFFFC008AF12 in hex Fix this by using unsigned ints in the function signature for vhost_vring_ioctl(). Signed-off-by: Sonny Rao <sonnyrao@chromium.org> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-08Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio/vhost updates from Michael Tsirkin: "virtio, vhost: fixes, cleanups, features This includes the disk/cache memory stats for for the virtio balloon, as well as multiple fixes and cleanups" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vhost: don't hold onto file pointer for VHOST_SET_LOG_FD vhost: don't hold onto file pointer for VHOST_SET_VRING_ERR vhost: don't hold onto file pointer for VHOST_SET_VRING_CALL ringtest: ring.c malloc & memset to calloc virtio_vop: don't kfree device on register failure virtio_pci: don't kfree device on register failure virtio: split device_register into device_initialize and device_add vhost: remove unused lock check flag in vhost_dev_cleanup() vhost: Remove the unused variable. virtio_blk: print capacity at probe time virtio: make VIRTIO a menuconfig to ease disabling it all virtio/ringtest: virtio_ring: fix up need_event math virtio/ringtest: fix up need_event math virtio: virtio_mmio: make of_device_ids const. firmware: Use PTR_ERR_OR_ZERO() virtio-mmio: Use PTR_ERR_OR_ZERO() vhost/scsi: Improve a size determination in four functions virtio_balloon: include disk/file caches memory statistics
2018-02-01vhost: don't hold onto file pointer for VHOST_SET_LOG_FDEric Biggers
We already hold a reference to the eventfd_ctx, which is sufficient; there's no need to hold a reference to the struct file as well. So get rid of vhost_dev->log_file. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com>
2018-02-01vhost: don't hold onto file pointer for VHOST_SET_VRING_ERREric Biggers
We already hold a reference to the eventfd_ctx, which is sufficient; there's no need to hold a reference to the struct file as well. So get rid of vhost_virtqueue->error. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com>
2018-02-01vhost: don't hold onto file pointer for VHOST_SET_VRING_CALLEric Biggers
We already hold a reference to the eventfd_ctx, which is sufficient; there's no need to hold a reference to the struct file as well. So get rid of vhost_virtqueue->call. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Jason Wang <jasowang@redhat.com>
2018-02-01vhost: remove unused lock check flag in vhost_dev_cleanup()夷则(Caspar)
In commit ea5d404655ba ("vhost: fix release path lockdep checks"), Michael added a flag to check whether we should hold a lock in vhost_dev_cleanup(), however, in commit 47283bef7ed3 ("vhost: move memory pointer to VQs"), RCU operations have been replaced by mutex, we can remove the no-longer-used `locked' parameter now. Signed-off-by: Caspar Zhang <jinli.zjl@alibaba-inc.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-01vhost: Remove the unused variable.Tonghao Zhang
The patch (7235acdb1) changed the way of the work flushing in which the queued seq, done seq, and the flushing are not used anymore. Then remove them now. Fixes: 7235acdb1 ("vhost: simplify work flushing") Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-11-28the rest of drivers/*: annotate ->poll() instancesAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27vhost: annotate vhost_pollAl Viro
its ->mask is POLL... bitmap Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
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>
2017-09-08lib/interval_tree: fast overlap detectionDavidlohr Bueso
Allow interval trees to quickly check for overlaps to avoid unnecesary tree lookups in interval_tree_iter_first(). As of this patch, all interval tree flavors will require using a 'rb_root_cached' such that we can have the leftmost node easily available. While most users will make use of this feature, those with special functions (in addition to the generic insert, delete, search calls) will avoid using the cached option as they can do funky things with insertions -- for example, vma_interval_tree_insert_after(). [jglisse@redhat.com: fix deadlock from typo vm_lock_anon_vma()] Link: http://lkml.kernel.org/r/20170808225719.20723-1-jglisse@redhat.com Link: http://lkml.kernel.org/r/20170719014603.19029-12-dave@stgolabs.net Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Jérôme Glisse <jglisse@redhat.com> Acked-by: Christian König <christian.koenig@amd.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Doug Ledford <dledford@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: David Airlie <airlied@linux.ie> Cc: Jason Wang <jasowang@redhat.com> Cc: Christian Benvenuti <benve@cisco.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-29Revert "vhost: cache used event for better performance"Jason Wang
This reverts commit 809ecb9bca6a9424ccd392d67e368160f8b76c92. Since it was reported to break vhost_net. We want to cache used event and use it to check for notification. The assumption was that guest won't move the event idx back, but this could happen in fact when 16 bit index wraps around after 64K entries. Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-20sched/wait: Rename wait_queue_t => wait_queue_entry_tIngo Molnar
Rename: wait_queue_t => wait_queue_entry_t 'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue", but in reality it's a queue *entry*. The 'real' queue is the wait queue head, which had to carry the name. Start sorting this out by renaming it to 'wait_queue_entry_t'. This also allows the real structure name 'struct __wait_queue' to lose its double underscore and become 'struct wait_queue_entry', which is the more canonical nomenclature for such data types. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02vhost: introduce O(1) vq metadata cacheJason Wang
When device IOTLB is enabled, all address translations were stored in interval tree. O(lgN) searching time could be slow for virtqueue metadata (avail, used and descriptors) since they were accessed much often than other addresses. So this patch introduces an O(1) array which points to the interval tree nodes that store the translations of vq metadata. Those array were update during vq IOTLB prefetching and were reset during each invalidation and tlb update. Each time we want to access vq metadata, this small array were queried before interval tree. This would be sufficient for static mappings but not dynamic mappings, we could do optimizations on top. Test were done with l2fwd in guest (2M hugepage): noiommu | before | after tx 1.32Mpps | 1.06Mpps(82%) | 1.30Mpps(98%) rx 2.33Mpps | 1.46Mpps(63%) | 2.29Mpps(98%) We can almost reach the same performance as noiommu mode. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-16vhost: cache used event for better performanceJason Wang
When event index was enabled, we need to fetch used event from userspace memory each time. This userspace fetch (with memory barrier) could be saved sometime when 1) caching used event and 2) if used event is ahead of new and old to new updating does not cross it, we're sure there's no need to notify guest. This will be useful for heavy tx load e.g guest pktgen test with Linux driver shows ~3.5% improvement. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-02vhost: new device IOTLB APIJason Wang
This patch tries to implement an device IOTLB for vhost. This could be used with userspace(qemu) implementation of DMA remapping to emulate an IOMMU for the guest. The idea is simple, cache the translation in a software device IOTLB (which is implemented as an interval tree) in vhost and use vhost_net file descriptor for reporting IOTLB miss and IOTLB update/invalidation. When vhost meets an IOTLB miss, the fault address, size and access can be read from the file. After userspace finishes the translation, it writes the translated address to the vhost_net file to update the device IOTLB. When device IOTLB is enabled by setting VIRTIO_F_IOMMU_PLATFORM all vq addresses set by ioctl are treated as iova instead of virtual address and the accessing can only be done through IOTLB instead of direct userspace memory access. Before each round or vq processing, all vq metadata is prefetched in device IOTLB to make sure no translation fault happens during vq processing. In most cases, virtqueues are contiguous even in virtual address space. The IOTLB translation for virtqueue itself may make it a little slower. We might add fast path cache on top of this patch. Signed-off-by: Jason Wang <jasowang@redhat.com> [mst: use virtio feature bit: VHOST_F_DEVICE_IOTLB -> VIRTIO_F_IOMMU_PLATFORM ] [mst: fix build warnings ] Signed-off-by: Michael S. Tsirkin <mst@redhat.com> [ weiyj.lk: missing unlock on error ] Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
2016-08-02vhost: convert pre sorted vhost memory array to interval treeJason Wang
Current pre-sorted memory region array has some limitations for future device IOTLB conversion: 1) need extra work for adding and removing a single region, and it's expected to be slow because of sorting or memory re-allocation. 2) need extra work of removing a large range which may intersect several regions with different size. 3) need trick for a replacement policy like LRU To overcome the above shortcomings, this patch convert it to interval tree which can easily address the above issue with almost no extra work. The patch could be used for: - Extend the current API and only let the userspace to send diffs of memory table. - Simplify Device IOTLB implementation. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-08-01vhost: lockless enqueuingJason Wang
We use spinlock to synchronize the work list now which may cause unnecessary contentions. So this patch switch to use llist to remove this contention. Pktgen tests shows about 5% improvement: Before: ~1300000 pps After: ~1370000 pps Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-11vhost_net: basic polling supportJason Wang
This patch tries to poll for new added tx buffer or socket receive queue for a while at the end of tx/rx processing. The maximum time spent on polling were specified through a new kind of vring ioctl. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-11vhost: introduce vhost_vq_avail_empty()Jason Wang
This patch introduces a helper which will return true if we're sure that the available ring is empty for a specific vq. When we're not sure, e.g vq access failure, return false instead. This could be used for busy polling code to exit the busy loop. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-11vhost: introduce vhost_has_work()Jason Wang
This path introduces a helper which can give a hint for whether or not there's a work queued in the work list. This could be used for busy polling code to exit the busy loop. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02vhost: rename vhost_init_used()Greg Kurz
Looking at how callers use this, maybe we should just rename init_used to vhost_vq_init_access. The _used suffix was a hint that we access the vq used ring. But maybe what callers care about is that it must be called after access_ok. Also, this function manipulates the vq->is_le field which isn't related to the vq used ring. This patch simply renames vhost_init_used() to vhost_vq_init_access() as suggested by Michael. No behaviour change. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-10-27vhost: fix performance on LE hostsMichael S. Tsirkin
commit 2751c9882b947292fcfb084c4f604e01724af804 ("vhost: cross-endian support for legacy devices") introduced a minor regression: even with cross-endian disabled, and even on LE host, vhost_is_little_endian is checking is_le flag so there's always a branch. To fix, simply check virtio_legacy_is_little_endian first. Cc: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-16vhost: move features to coreMichael S. Tsirkin
virtio 1 and any layout are core features, move them there. This fixes vhost test. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-06-01vhost: cross-endian support for legacy devicesGreg Kurz
This patch brings cross-endian support to vhost when used to implement legacy virtio devices. Since it is a relatively rare situation, the feature availability is controlled by a kernel config option (not set by default). The vq->is_le boolean field is added to cache the endianness to be used for ring accesses. It defaults to native endian, as expected by legacy virtio devices. When the ring gets active, we force little endian if the device is modern. When the ring is deactivated, we revert to the native endian default. If cross-endian was compiled in, a vq->user_be boolean field is added so that userspace may request a specific endianness. This field is used to override the default when activating the ring of a legacy device. It has no effect on modern devices. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>