summaryrefslogtreecommitdiff
path: root/drivers/char/virtio_console.c
AgeCommit message (Collapse)AuthorFilesLines
2023-12-08tty: hvc: convert to u8 and size_tJiri Slaby (SUSE)1-5/+5
Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. Signed-off-by: "Jiri Slaby (SUSE)" <jirislaby@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linuxppc-dev@lists.ozlabs.org Cc: virtualization@lists.linux.dev Cc: linux-riscv@lists.infradead.org Link: https://lore.kernel.org/r/20231206073712.17776-13-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-08tty: virtio: drop virtio_cons_early_init()Jiri Slaby (SUSE)1-48/+0
The last user of virtio_cons_early_init() was dropped in commit 7fb2b2d51244 ("s390/virtio: remove the old KVM virtio transport"). So now, drop virtio_cons_early_init() and the logic and headers behind too. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Acked-by: Jason Wang <jasowang@redhat.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Cc: linux-alpha@vger.kernel.org Cc: virtualization@lists.linux.dev Link: https://lore.kernel.org/r/20231130113001.29154-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25virtio_console: Annotate struct port_buffer with __counted_byKees Cook1-1/+1
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct port_buffer. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: virtualization@lists.linux-foundation.org Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org> Reviewed-by: Amit Shah <amit@kernel.org> Link: https://lore.kernel.org/r/20230922175115.work.059-kees@kernel.org Signed-off-by: Kees Cook <keescook@chromium.org>
2023-07-04Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-0/+1
Pull virtio updates from Michael Tsirkin: - resume support in vdpa/solidrun - structure size optimizations in virtio_pci - new pds_vdpa driver - immediate initialization mechanism for vdpa/ifcvf - interrupt bypass for vdpa/mlx5 - multiple worker support for vhost - viirtio net in Intel F2000X-PL support for vdpa/ifcvf - fixes, cleanups all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (48 commits) vhost: Make parameter name match of vhost_get_vq_desc() vduse: fix NULL pointer dereference vhost: Allow worker switching while work is queueing vhost_scsi: add support for worker ioctls vhost: allow userspace to create workers vhost: replace single worker pointer with xarray vhost: add helper to parse userspace vring state/file vhost: remove vhost_work_queue vhost_scsi: flush IO vqs then send TMF rsp vhost_scsi: convert to vhost_vq_work_queue vhost_scsi: make SCSI cmd completion per vq vhost_sock: convert to vhost_vq_work_queue vhost: convert poll work to be vq based vhost: take worker or vq for flushing vhost: take worker or vq instead of dev for queueing vhost, vhost_net: add helper to check if vq has work vhost: add vhost_worker pointer to vhost_virtqueue vhost: dynamically allocate vhost_worker vhost: create worker at end of vhost_dev_set_owner virtio_bt: call scheduler when we free unused buffs ...
2023-07-03virtio-console: call scheduler when we free unused buffsXianting Tian1-0/+1
For virtio-net we were getting CPU stall warnings, and fixed it by calling the scheduler: see f8bb51043945 ("virtio_net: suppress cpu stall when free_unused_bufs"). This driver is similar so theoretically the same logic applies. Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com> Message-Id: <20230609131817.712867-3-xianting.tian@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-06-23virtio_console: make port class a static const structureIvan Orlov1-13/+11
Now that the driver core allows for struct class to be in read-only memory, remove the class field of the ports_driver_data structure and create the port_class static class structure declared at build time which places it into read-only memory, instead of having it to be dynamically allocated at load time. Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: virtualization@lists.linux-foundation.org Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com> Link: https://lore.kernel.org/r/20230620143751.578239-16-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-17driver core: class: remove module * from class_create()Greg Kroah-Hartman1-1/+1
The module pointer in class_create() never actually did anything, and it shouldn't have been requred to be set as a parameter even if it did something. So just remove it and fix up all callers of the function in the kernel tree at the same time. Cc: "Rafael J. Wysocki" <rafael@kernel.org> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Link: https://lore.kernel.org/r/20230313181843.1207845-4-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-20virtio_console: Use strscpy() to instead of strncpy()Bo Liu1-3/+2
The implementation of strscpy() is more robust and safer. That's now the recommended way to copy NUL-terminated strings. Signed-off-by: Bo Liu <liubo03@inspur.com> Link: https://lore.kernel.org/r/20230118012944.2436-1-liubo03@inspur.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-23virtio_console: Introduce an ID allocator for virtual console numbersCédric Le Goater1-15/+11
When a virtio console port is initialized, it is registered as an hvc console using a virtual console number. If a KVM guest is started with multiple virtio console devices, the same vtermno (or virtual console number) can be used to allocate different hvc consoles, which leads to various communication problems later on. This is also reported in debugfs : # grep vtermno /sys/kernel/debug/virtio-ports/* /sys/kernel/debug/virtio-ports/vport1p1:console_vtermno: 1 /sys/kernel/debug/virtio-ports/vport2p1:console_vtermno: 1 /sys/kernel/debug/virtio-ports/vport3p1:console_vtermno: 2 /sys/kernel/debug/virtio-ports/vport4p1:console_vtermno: 3 Replace the next_vtermno global with an ID allocator and start the allocation at 1 as it is today. Also recycle IDs when a console port is removed. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: Thomas Huth <thuth@redhat.com> Link: https://lore.kernel.org/r/20221122134643.376184-1-clg@kaod.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-28Merge tag 'char-misc-5.18-rc1' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc and other driver updates from Greg KH: "Here is the big set of char/misc and other small driver subsystem updates for 5.18-rc1. Included in here are merges from driver subsystems which contain: - iio driver updates and new drivers - fsi driver updates - fpga driver updates - habanalabs driver updates and support for new hardware - soundwire driver updates and new drivers - phy driver updates and new drivers - coresight driver updates - icc driver updates Individual changes include: - mei driver updates - interconnect driver updates - new PECI driver subsystem added - vmci driver updates - lots of tiny misc/char driver updates All of these have been in linux-next for a while with no reported problems" * tag 'char-misc-5.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (556 commits) firmware: google: Properly state IOMEM dependency kgdbts: fix return value of __setup handler firmware: sysfb: fix platform-device leak in error path firmware: stratix10-svc: add missing callback parameter on RSU arm64: dts: qcom: add non-secure domain property to fastrpc nodes misc: fastrpc: Add dma handle implementation misc: fastrpc: Add fdlist implementation misc: fastrpc: Add helper function to get list and page misc: fastrpc: Add support to secure memory map dt-bindings: misc: add fastrpc domain vmid property misc: fastrpc: check before loading process to the DSP misc: fastrpc: add secure domain support dt-bindings: misc: add property to support non-secure DSP misc: fastrpc: Add support to get DSP capabilities misc: fastrpc: add support for FASTRPC_IOCTL_MEM_MAP/UNMAP misc: fastrpc: separate fastrpc device from channel context dt-bindings: nvmem: brcm,nvram: add basic NVMEM cells dt-bindings: nvmem: make "reg" property optional nvmem: brcm_nvram: parse NVRAM content into NVMEM cells nvmem: dt-bindings: Fix the error of dt-bindings check ...
2022-03-18virtio_console: eliminate anonymous module_init & module_exitRandy Dunlap1-4/+4
Eliminate anonymous module_init() and module_exit(), which can lead to confusion or ambiguity when reading System.map, crashes/oops/bugs, or an initcall_debug log. Give each of these init and exit functions unique driver-specific names to eliminate the anonymous names. Example 1: (System.map) ffffffff832fc78c t init ffffffff832fc79e t init ffffffff832fc8f8 t init Example 2: (initcall_debug log) calling init+0x0/0x12 @ 1 initcall init+0x0/0x12 returned 0 after 15 usecs calling init+0x0/0x60 @ 1 initcall init+0x0/0x60 returned 0 after 2 usecs calling init+0x0/0x9a @ 1 initcall init+0x0/0x9a returned 0 after 74 usecs Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Amit Shah <amit@kernel.org> Cc: virtualization@lists.linux-foundation.org Cc: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20220316192010.19001-3-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-03-04virtio_console: break out of buf poll on removeMichael S. Tsirkin1-0/+7
A common pattern for device reset is currently: vdev->config->reset(vdev); .. cleanup .. reset prevents new interrupts from arriving and waits for interrupt handlers to finish. However if - as is common - the handler queues a work request which is flushed during the cleanup stage, we have code adding buffers / trying to get buffers while device is reset. Not good. This was reproduced by running modprobe virtio_console modprobe -r virtio_console in a loop. Fix this up by calling virtio_break_device + flush before reset. Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1786239 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-15virtio: wrap config->reset callsMichael S. Tsirkin1-2/+2
This will enable cleanups down the road. The idea is to disable cbs, then add "flush_queued_cbs" callback as a parameter, this way drivers can flush any work queued after callbacks have been disabled. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20211013105226.20225-1-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-11-01virtio_console: validate max_nr_ports before trying to use itJason Wang1-0/+9
We calculate nr_ports based on the max_nr_ports: nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2; If the device advertises a large max_nr_ports, we will end up with a integer overflow. Fixing this by validating the max_nr_ports and fail the probe for invalid max_nr_ports in this case. Cc: Amit Shah <amit@kernel.org> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20211019070152.8236-3-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-07-03virtio_console: Assure used length from device is limitedXie Yongji1-2/+2
The buf->len might come from an untrusted device. This ensures the value would not exceed the size of the buffer to avoid data corruption or loss. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Acked-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210525125622.1203-1-xieyongji@bytedance.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-03-10virtio_console: remove pointless check for debugfs_create_dir()Greg Kroah-Hartman1-14/+9
It is impossible for debugfs_create_dir() to return NULL, so checking for it gives people a false sense that they actually are doing something if an error occurs. As there is no need to ever change kernel logic if debugfs is working "properly" or not, there is no need to check the return value of debugfs calls, so remove the checks here as they will never be triggered and are wrong. Cc: Amit Shah <amit@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: virtualization@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Amit Shah <amit@kernel.org> Link: https://lore.kernel.org/r/20210216150410.3844635-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-09virtio: virtio_console: fix DMA memory allocation for rproc serialAlexander Lobakin1-4/+4
Since commit 086d08725d34 ("remoteproc: create vdev subdevice with specific dma memory pool"), every remoteproc has a DMA subdevice ("remoteprocX#vdevYbuffer") for each virtio device, which inherits DMA capabilities from the corresponding platform device. This allowed to associate different DMA pools with each vdev, and required from virtio drivers to perform DMA operations with the parent device (vdev->dev.parent) instead of grandparent (vdev->dev.parent->parent). virtio_rpmsg_bus was already changed in the same merge cycle with commit d999b622fcfb ("rpmsg: virtio: allocate buffer from parent"), but virtio_console did not. In fact, operations using the grandparent worked fine while the grandparent was the platform device, but since commit c774ad010873 ("remoteproc: Fix and restore the parenting hierarchy for vdev") this was changed, and now the grandparent device is the remoteproc device without any DMA capabilities. So, starting v5.8-rc1 the following warning is observed: [ 2.483925] ------------[ cut here ]------------ [ 2.489148] WARNING: CPU: 3 PID: 101 at kernel/dma/mapping.c:427 0x80e7eee8 [ 2.489152] Modules linked in: virtio_console(+) [ 2.503737] virtio_rpmsg_bus rpmsg_core [ 2.508903] [ 2.528898] <Other modules, stack and call trace here> [ 2.913043] [ 2.914907] ---[ end trace 93ac8746beab612c ]--- [ 2.920102] virtio-ports vport1p0: Error allocating inbufs kernel/dma/mapping.c:427 is: WARN_ON_ONCE(!dev->coherent_dma_mask); obviously because the grandparent now is remoteproc dev without any DMA caps: [ 3.104943] Parent: remoteproc0#vdev1buffer, grandparent: remoteproc0 Fix this the same way as it was for virtio_rpmsg_bus, using just the parent device (vdev->dev.parent, "remoteprocX#vdevYbuffer") for DMA operations. This also allows now to reserve DMA pools/buffers for rproc serial via Device Tree. Fixes: c774ad010873 ("remoteproc: Fix and restore the parenting hierarchy for vdev") Cc: stable@vger.kernel.org # 5.1+ Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Alexander Lobakin <alobakin@pm.me> Date: Thu, 5 Nov 2020 11:10:24 +0800 Link: https://lore.kernel.org/r/AOKowLclCbOCKxyiJ71WeNyuAAj2q8EUtxrXbyky5E@cp7-web-042.plabs.ch Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-20Merge v5.8-rc6 into char-misc-nextGreg Kroah-Hartman1-1/+2
We need the char/misc fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10virtio: virtio_console: add missing MODULE_DEVICE_TABLE() for rproc serialAlexander Lobakin1-1/+2
rproc_serial_id_table lacks an exposure to module devicetable, so when remoteproc firmware requests VIRTIO_ID_RPROC_SERIAL, no uevent is generated and no module autoloading occurs. Add missing MODULE_DEVICE_TABLE() annotation and move the existing one for VIRTIO_ID_CONSOLE right to the table itself. Fixes: 1b6370463e88 ("virtio_console: Add support for remoteproc serial") Cc: <stable@vger.kernel.org> # v3.8+ Signed-off-by: Alexander Lobakin <alobakin@pm.me> Reviewed-by: Amit Shah <amit@kernel.org> Link: https://lore.kernel.org/r/x7C_CbeJtoGMy258nwAXASYz3xgFMFpyzmUvOyZzRnQrgWCREBjaqBOpAUS7ol4NnZYvSVwmTsCG0Ohyfvta-ygw6HMHcoeKK0C3QFiAO_Q=@pm.me Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10virtio_console: Constify some static variablesRikard Falkeborn1-4/+4
The id_table and feature_table pointers in struct virtio_driver are pointers to const. Mark the corresponding static variables const to allow the compiler to put them in read-only memory. Before: text data bss dec hex filename 25447 713 76 26236 667c drivers/char/virtio_console.o After: text data bss dec hex filename 25488 673 76 26237 667d drivers/char/virtio_console.o Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Amit Shah <amit@kernel.org> Link: https://lore.kernel.org/r/20200701200950.30314-6-rikard.falkeborn@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-20fs: rename pipe_buf ->steal to ->try_stealChristoph Hellwig1-1/+1
And replace the arcane return value convention with a simple bool where true means success and false means failure. [AV: braino fix folded in] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-14char: virtio: Replace zero-length array with flexible-array memberGustavo A. R. Silva1-1/+1
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertenly introduced[3] to the codebase from now on. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Link: https://lore.kernel.org/r/20200211222941.GA7657@embeddedor Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-01Merge tag 'notifications-pipe-prep-20191115' of ↵Linus Torvalds1-9/+7
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs Pull pipe rework from David Howells: "This is my set of preparatory patches for building a general notification queue on top of pipes. It makes a number of significant changes: - It removes the nr_exclusive argument from __wake_up_sync_key() as this is always 1. This prepares for the next step: - Adds wake_up_interruptible_sync_poll_locked() so that poll can be woken up from a function that's holding the poll waitqueue spinlock. - Change the pipe buffer ring to be managed in terms of unbounded head and tail indices rather than bounded index and length. This means that reading the pipe only needs to modify one index, not two. - A selection of helper functions are provided to query the state of the pipe buffer, plus a couple to apply updates to the pipe indices. - The pipe ring is allowed to have kernel-reserved slots. This allows many notification messages to be spliced in by the kernel without allowing userspace to pin too many pages if it writes to the same pipe. - Advance the head and tail indices inside the pipe waitqueue lock and use wake_up_interruptible_sync_poll_locked() to poke poll without having to take the lock twice. - Rearrange pipe_write() to preallocate the buffer it is going to write into and then drop the spinlock. This allows kernel notifications to then be added the ring whilst it is filling the buffer it allocated. The read side is stalled because the pipe mutex is still held. - Don't wake up readers on a pipe if there was already data in it when we added more. - Don't wake up writers on a pipe if the ring wasn't full before we removed a buffer" * tag 'notifications-pipe-prep-20191115' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: pipe: Remove sync on wake_ups pipe: Increase the writer-wakeup threshold to reduce context-switch count pipe: Check for ring full inside of the spinlock in pipe_write() pipe: Remove redundant wakeup from pipe_write() pipe: Rearrange sequence in pipe_write() to preallocate slot pipe: Conditionalise wakeup in pipe_read() pipe: Advance tail pointer inside of wait spinlock in pipe_read() pipe: Allow pipes to have kernel-reserved slots pipe: Use head and tail pointers for the ring, not cursor and length Add wake_up_interruptible_sync_poll_locked() Remove the nr_exclusive argument from __wake_up_sync_key() pipe: Reduce #inclusion of pipe_fs_i.h
2019-11-19virtio_console: allocate inbufs in add_port() only if it is neededLaurent Vivier1-15/+13
When we hot unplug a virtserialport and then try to hot plug again, it fails: (qemu) chardev-add socket,id=serial0,path=/tmp/serial0,server,nowait (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 (qemu) device_del serial0 (qemu) device_add virtserialport,bus=virtio-serial0.0,nr=2,\ chardev=serial0,id=serial0,name=serial0 kernel error: virtio-ports vport2p2: Error allocating inbufs qemu error: virtio-serial-bus: Guest failure in adding port 2 for device \ virtio-serial0.0 This happens because buffers for the in_vq are allocated when the port is added but are not released when the port is unplugged. They are only released when virtconsole is removed (see a7a69ec0d8e4) To avoid the problem and to be symmetric, we could allocate all the buffers in init_vqs() as they are released in remove_vqs(), but it sounds like a waste of memory. Rather than that, this patch changes add_port() logic to ignore ENOSPC error in fill_queue(), which means queue has already been filled. Fixes: a7a69ec0d8e4 ("virtio_console: free buffers after reset") Cc: mst@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-31pipe: Use head and tail pointers for the ring, not cursor and lengthDavid Howells1-9/+7
Convert pipes to use head and tail pointers for the buffer ring rather than pointer and length as the latter requires two atomic ops to update (or a combined op) whereas the former only requires one. (1) The head pointer is the point at which production occurs and points to the slot in which the next buffer will be placed. This is equivalent to pipe->curbuf + pipe->nrbufs. The head pointer belongs to the write-side. (2) The tail pointer is the point at which consumption occurs. It points to the next slot to be consumed. This is equivalent to pipe->curbuf. The tail pointer belongs to the read-side. (3) head and tail are allowed to run to UINT_MAX and wrap naturally. They are only masked off when the array is being accessed, e.g.: pipe->bufs[head & mask] This means that it is not necessary to have a dead slot in the ring as head == tail isn't ambiguous. (4) The ring is empty if "head == tail". A helper, pipe_empty(), is provided for this. (5) The occupancy of the ring is "head - tail". A helper, pipe_occupancy(), is provided for this. (6) The number of free slots in the ring is "pipe->ring_size - occupancy". A helper, pipe_space_for_user() is provided to indicate how many slots userspace may use. (7) The ring is full if "head - tail >= pipe->ring_size". A helper, pipe_full(), is provided for this. Signed-off-by: David Howells <dhowells@redhat.com>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner1-14/+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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> 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/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-27virtio_console: initialize vtermno value for portsPankaj Gupta1-1/+2
For regular serial ports we do not initialize value of vtermno variable. A garbage value is assigned for non console ports. The value can be observed as a random integer with [1]. [1] vim /sys/kernel/debug/virtio-ports/vport*p* This patch initialize the value of vtermno for console serial ports to '1' and regular serial ports are initiaized to '0'. Reported-by: siliu@redhat.com Signed-off-by: Pankaj Gupta <pagupta@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-06char: virtio: Change to use DEFINE_SHOW_ATTRIBUTE macroYangtao Li1-14/+3
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16virtio: virtconsole: Use seq_file for debugfs operationsTuomas Tynkkynen1-38/+22
Simplifies the code and is more conventional to what's used in the rest of the kernel for debugfs ops. Signed-off-by: Tuomas Tynkkynen <tuomas@tuxera.com> Reviewed-by: Amit Shah <amit@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-13treewide: kmalloc() -> kmalloc_array()Kees Cook1-7/+8
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-13Convert virtio_console to struct_sizeMatthew Wilcox1-2/+1
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Kees Cook <keescook@chromium.org>
2018-04-25virtio_console: reset on out of memoryMichael S. Tsirkin1-7/+10
When out of memory and we can't add ctrl vq buffers, probe fails. Unfortunately the error handling is out of spec: it calls del_vqs without bothering to reset the device first. To fix, call the full cleanup function in this case. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-04-25virtio_console: move removal codeMichael S. Tsirkin1-36/+36
Will make it reusable for error handling. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-04-25virtio_console: drop custom control queue cleanupMichael S. Tsirkin1-17/+0
We now cleanup all VQs on device removal - no need to handle the control VQ specially. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-04-25virtio_console: free buffers after resetMichael S. Tsirkin1-25/+24
Console driver is out of spec. The spec says: A driver MUST NOT decrement the available idx on a live virtqueue (ie. there is no way to “unexpose” buffers). and it does exactly that by trying to detach unused buffers without doing a device reset first. Defer detaching the buffers until device unplug. Of course this means we might get an interrupt for a vq without an attached port now. Handle that by discarding the consumed buffer. Reported-by: Tiwei Bie <tiwei.bie@intel.com> Fixes: b3258ff1d6 ("virtio: Decrement avail idx on buffer detach") Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-04-25virtio_console: don't tie bufs to a vqMichael S. Tsirkin1-7/+7
an allocated buffer doesn't need to be tied to a vq - only vq->vdev is ever used. Pass the function the just what it needs - the vdev. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-02-12vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds1-4/+4
This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-28the rest of drivers/*: annotate ->poll() instancesAl Viro1-2/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-09-12Merge tag 'dma-mapping-4.14' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds1-3/+0
Pull dma-mapping updates from Christoph Hellwig: - removal of the old dma_alloc_noncoherent interface - remove unused flags to dma_declare_coherent_memory - restrict OF DMA configuration to specific physical busses - use the iommu mailing list for dma-mapping questions and patches * tag 'dma-mapping-4.14' of git://git.infradead.org/users/hch/dma-mapping: dma-coherent: fix dma_declare_coherent_memory() logic error ARM: imx: mx31moboard: Remove unused 'dma' variable dma-coherent: remove an unused variable MAINTAINERS: use the iommu list for the dma-mapping subsystem dma-coherent: remove the DMA_MEMORY_MAP and DMA_MEMORY_IO flags dma-coherent: remove the DMA_MEMORY_INCLUDES_CHILDREN flag of: restrict DMA configuration dma-mapping: remove dma_alloc_noncoherent and dma_free_noncoherent i825xx: switch to switch to dma_alloc_attrs au1000_eth: switch to dma_alloc_attrs sgiseeq: switch to dma_alloc_attrs dma-mapping: reduce dma_mapping_error inline bloat
2017-09-05Merge tag 'char-misc-4.14-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big char/misc driver update for 4.14-rc1. Lots of different stuff in here, it's been an active development cycle for some reason. Highlights are: - updated binder driver, this brings binder up to date with what shipped in the Android O release, plus some more changes that happened since then that are in the Android development trees. - coresight updates and fixes - mux driver file renames to be a bit "nicer" - intel_th driver updates - normal set of hyper-v updates and changes - small fpga subsystem and driver updates - lots of const code changes all over the driver trees - extcon driver updates - fmc driver subsystem upadates - w1 subsystem minor reworks and new features and drivers added - spmi driver updates Plus a smattering of other minor driver updates and fixes. All of these have been in linux-next with no reported issues for a while" * tag 'char-misc-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (244 commits) ANDROID: binder: don't queue async transactions to thread. ANDROID: binder: don't enqueue death notifications to thread todo. ANDROID: binder: Don't BUG_ON(!spin_is_locked()). ANDROID: binder: Add BINDER_GET_NODE_DEBUG_INFO ioctl ANDROID: binder: push new transactions to waiting threads. ANDROID: binder: remove proc waitqueue android: binder: Add page usage in binder stats android: binder: fixup crash introduced by moving buffer hdr drivers: w1: add hwmon temp support for w1_therm drivers: w1: refactor w1_slave_show to make the temp reading functionality separate drivers: w1: add hwmon support structures eeprom: idt_89hpesx: Support both ACPI and OF probing mcb: Fix an error handling path in 'chameleon_parse_cells()' MCB: add support for SC31 to mcb-lpc mux: make device_type const char: virtio: constify attribute_group structures. Documentation/ABI: document the nvmem sysfs files lkdtm: fix spelling mistake: "incremeted" -> "incremented" perf: cs-etm: Fix ETMv4 CONFIGR entry in perf.data file nvmem: include linux/err.h from header ...
2017-09-01dma-coherent: remove the DMA_MEMORY_INCLUDES_CHILDREN flagChristoph Hellwig1-3/+0
This flag was never implemented or used. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2017-08-28char: virtio: constify attribute_group structures.Arvind Yadav1-1/+1
attribute_group are not supposed to change at runtime. All functions working with attribute_group provided by <linux/sysfs.h> work with const attribute_group. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-24x86/lguest: Remove lguest supportJuergen Gross1-1/+1
Lguest seems to be rather unused these days. It has seen only patches ensuring it still builds the last two years and its official state is "Odd Fixes". Remove it in order to be able to clean up the paravirt code. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: boris.ostrovsky@oracle.com Cc: lguest@lists.ozlabs.org Cc: rusty@rustcorp.com.au Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-10Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds1-3/+3
Pull virtio updates from Michael Tsirkin: "Fixes, cleanups, performance A bunch of changes to virtio, most affecting virtio net. Also ptr_ring batched zeroing - first of batching enhancements that seems ready." * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: s390/virtio: change maintainership tools/virtio: fix spelling mistake: "wakeus" -> "wakeups" virtio_net: tidy a couple debug statements ptr_ring: support testing different batching sizes ringtest: support test specific parameters ptr_ring: batch ring zeroing virtio: virtio_driver doc virtio_net: don't reset twice on XDP on/off virtio_net: fix support for small rings virtio_net: reduce alignment for buffers virtio_net: rework mergeable buffer handling virtio_net: allow specifying context for rx virtio: allow extra context per descriptor tools/virtio: fix build breakage virtio: add context flag to find vqs virtio: wrap find_vqs ringtest: fix an assert statement
2017-05-05Merge tag 'char-misc-4.12-rc1' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver updates from Greg KH: "Here is the big set of new char/misc driver drivers and features for 4.12-rc1. There's lots of new drivers added this time around, new firmware drivers from Google, more auxdisplay drivers, extcon drivers, fpga drivers, and a bunch of other driver updates. Nothing major, except if you happen to have the hardware for these drivers, and then you will be happy :) All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (136 commits) firmware: google memconsole: Fix return value check in platform_memconsole_init() firmware: Google VPD: Fix return value check in vpd_platform_init() goldfish_pipe: fix build warning about using too much stack. goldfish_pipe: An implementation of more parallel pipe fpga fr br: update supported version numbers fpga: region: release FPGA region reference in error path fpga altera-hps2fpga: disable/unprepare clock on error in alt_fpga_bridge_probe() mei: drop the TODO from samples firmware: Google VPD sysfs driver firmware: Google VPD: import lib_vpd source files misc: lkdtm: Add volatile to intentional NULL pointer reference eeprom: idt_89hpesx: Add OF device ID table misc: ds1682: Add OF device ID table misc: tsl2550: Add OF device ID table w1: Remove unneeded use of assert() and remove w1_log.h w1: Use kernel common min() implementation uio_mf624: Align memory regions to page size and set correct offsets uio_mf624: Refactor memory info initialization uio: Allow handling of non page-aligned memory regions hangcheck-timer: Fix typo in comment ...
2017-05-02virtio: wrap find_vqsMichael S. Tsirkin1-3/+3
We are going to add more parameters to find_vqs, let's wrap the call so we don't need to tweak all drivers every time. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-07virtio_console: fix uninitialized variable useMichael S. Tsirkin1-2/+4
We try to disable callbacks on c_ivq even without multiport even though that vq is not initialized in this configuration. Fixes: c743d09dbd01 ("virtio: console: Disable callbacks for virtqueues at start of S4 freeze") Suggested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-03-17drivers/char: Convert remaining use of pr_warning to pr_warnJoe Perches1-1/+1
To enable eventual removal of pr_warning This makes pr_warn use consistent for drivers/char Prior to this patch, there were 1 use of pr_warning and 40 uses of pr_warn in drivers/char Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Amit Shah <amit@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02virtio-console: avoid DMA from stackOmar Sandoval1-2/+10
put_chars() stuffs the buffer it gets into an sg, but that buffer may be on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it manifested as printks getting turned into NUL bytes). Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com>
2017-02-27virtio: allow drivers to request IRQ affinity when creating VQsChristoph Hellwig1-1/+1
Add a struct irq_affinity pointer to the find_vqs methods, which if set is used to tell the PCI layer to create the MSI-X vectors for our I/O virtqueues with the proper affinity from the start. Compared to after the fact affinity hints this gives us an instantly working setup and allows to allocate the irq descritors node-local and avoid interconnect traffic. Last but not least this will allow blk-mq queues are created based on the interrupt affinity for storage drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>