From: Diederik de Groot Date: Mon, 1 Oct 2018 23:00:05 +0000 (+0200) Subject: Virtio_Balloon implementation for DragonFly X-Git-Tag: v5.5.0~82 X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/95fbc42e816925ffb64f54aff73b17ea73ba1a70 Virtio_Balloon implementation for DragonFly - Initial check-in of fbsd virtio_balloon (freebsd/freebsd@1537078) - Update virtio_balloon man page - Fix vtballoon_alloc_intrs to deal nicely with number of provided interrupts. - Use a backoff scheme when allocating vm_pages: - VM_ALLOC_NORMAL for normal (low memory presure) situation; - VM_ALLOC_SYSTEM + increased sleep timeout, for high memory presure circumstances. The latter will allow the system to swap other pages out if necessary. - Implemented suggestions made by ivadasz - Added virtio_teardown_intr handling to vtballoon_detach - Added config_change_intr handling - Fixed virtio_setup_intr - Add debug_level sysctl for tracing. - Add collection of guest memory/pagefault statistics - Completed/Updated header definitions - Don't use VM_ALLOC_INTERRUPT. Add better inflate/deflate debug output to thread_sleep function - Don't collect stats when initialially loaded (Reported by tuxillo). --- diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile index 29fe17b397..4fffa4387c 100644 --- a/share/man/man4/Makefile +++ b/share/man/man4/Makefile @@ -379,6 +379,7 @@ MAN= aac.4 \ viapm.4 \ vinum.4 \ virtio.4 \ + virtio_balloon.4 \ virtio_blk.4 \ virtio_random.4 \ virtio_scsi.4 \ diff --git a/share/man/man4/virtio.4 b/share/man/man4/virtio.4 index 73c9a23fcf..29c39ea472 100644 --- a/share/man/man4/virtio.4 +++ b/share/man/man4/virtio.4 @@ -24,7 +24,7 @@ .\" .\" $FreeBSD: head/share/man/man4/virtio.4 273515 2014-10-23 04:47:32Z bryanv $ .\" -.Dd September 30, 2018 +.Dd October 26, 2018 .Dt VIRTIO 4 .Os .Sh NAME @@ -74,11 +74,11 @@ device driver. An emulated SCSI HBA is provided by the .Xr virtio_scsi 4 device driver. -.\".It Nm Balloon -.\"A pseudo-device to allow the VM to release memory back to the hypervisor is -.\"provided by the -.\".Xr virtio_balloon 4 -.\"device driver. +.It Nm Balloon +A pseudo-device to allow the VM to release memory back to the hypervisor is +provided by the +.Xr virtio_balloon 4 +device driver. .El .Sh LOADER TUNABLES Tunables can be set at the @@ -91,7 +91,7 @@ This tunable disables MSI-X interrupt usage. The default value is 0 (use MSI-X interrupts if available). .El .Sh SEE ALSO -.\".Xr virtio_balloon 4 , +.Xr virtio_balloon 4 , .Xr virtio_blk 4 , .\".Xr virtio_console 4 , .Xr virtio_random 4 , @@ -105,3 +105,6 @@ Support for VirtIO first appeared in .Fx support for VirtIO was first added by .An Bryan Venteicher Aq Mt bryanv@FreeBSD.org . +.Pp +.Dx support for Virtio Memory Balloon adapted by +.An Diederik de Groot Aq Mt info@talon.nl . diff --git a/share/man/man4/virtio_balloon.4 b/share/man/man4/virtio_balloon.4 new file mode 100644 index 0000000000..b9c8336416 --- /dev/null +++ b/share/man/man4/virtio_balloon.4 @@ -0,0 +1,77 @@ +.\" Copyright (c) 2011 Bryan Venteicher +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.Dd October 26, 2018 +.Dt VIRTIO_BALLOON 4 +.Os +.Sh NAME +.Nm virtio_balloon +.Nd VirtIO Memory Balloon driver +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following lines in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device virtio_balloon" +.Ed +.Pp +Alternatively, to load the driver as a +module at boot time, place the following line in +.Xr loader.conf 5 : +.Bd -literal -offset indent +virtio_balloon_load="YES" +.Ed +.Sh DESCRIPTION +The +.Nm +device driver provides support for VirtIO memory balloon devices. +.Pp +The memory balloon allows the guest to, at the request of the +hypervisor, return memory allocated to the hypervisor so it can +be made available to other guests. +The hypervisor can later signal the balloon to return the memory. +.Sh EXAMPLE: +.Bd -literal +(vmguest) # kldload virtio_balloon +(vmguest) # sysctl dev.vtballoon.desired +dev.vtballoon.0.desired: 0 +(vmguest) # sysctl dev.vtballoon.current +dev.vtballoon.0.current: 0 + +(vmhost) # virsh qemu-monitor-command --domain --hmp 'balloon 2000' + +(vmguest) # sysctl dev.vtballoon.desired +dev.vtballoon.0.desired: 536576 +(vmguest) # sysctl dev.vtballoon.current +dev.vtballoon.0.current: 536576 +.Ed +.Sh SEE ALSO +.Xr virtio 4 +.Sh HISTORY +The +.Nm +driver was written by +.An Bryan Venteicher Aq Mt bryanv@FreeBSD.org . +It first appeared in +.Fx 9.0 . diff --git a/sys/conf/files b/sys/conf/files index bfa5496525..a97a49c0e3 100644 --- a/sys/conf/files +++ b/sys/conf/files @@ -2924,6 +2924,7 @@ dev/virtual/hyperv/vmbus/vmbus.c optional vmbus # # virtio support # +dev/virtual/virtio/balloon/virtio_balloon.c optional virtio_balloon virtio dev/virtual/virtio/block/virtio_blk.c optional virtio_blk virtio dev/virtual/virtio/random/virtio_random.c optional virtio_random virtio dev/virtual/virtio/scsi/virtio_scsi.c optional virtio_scsi virtio diff --git a/sys/config/LINT64 b/sys/config/LINT64 index 3ddc382a6c..71c0eb4070 100644 --- a/sys/config/LINT64 +++ b/sys/config/LINT64 @@ -2121,6 +2121,7 @@ device vmbus # Virtio support # device virtio # Generic VirtIO bus/PCI interface (required) +device virtio_balloon # VirtIO Memory Balloon device device virtio_blk # VirtIO Block device device virtio_random # VirtIO Entropy device device virtio_scsi # VirtIO SCSI device diff --git a/sys/config/X86_64_GENERIC b/sys/config/X86_64_GENERIC index 3e47f54c4e..e3066a21fa 100644 --- a/sys/config/X86_64_GENERIC +++ b/sys/config/X86_64_GENERIC @@ -138,6 +138,7 @@ device twe # 3ware Escalade 7000/8000's # VirtIO support device virtio # VirtIO core +device virtio_balloon # VirtIO Memory Balloon device device virtio_blk # VirtIO disk driver device virtio_scsi # VirtIO SCSI driver device vtnet # VirtIO network driver diff --git a/sys/dev/virtual/virtio/Makefile b/sys/dev/virtual/virtio/Makefile index a53fc646c7..389b118af2 100644 --- a/sys/dev/virtual/virtio/Makefile +++ b/sys/dev/virtual/virtio/Makefile @@ -23,6 +23,6 @@ # SUCH DAMAGE. # -SUBDIR= virtio pci block net random scsi +SUBDIR= virtio pci balloon block net random scsi .include diff --git a/sys/dev/virtual/virtio/Makefile b/sys/dev/virtual/virtio/balloon/Makefile similarity index 84% copy from sys/dev/virtual/virtio/Makefile copy to sys/dev/virtual/virtio/balloon/Makefile index a53fc646c7..99f36abdc4 100644 --- a/sys/dev/virtual/virtio/Makefile +++ b/sys/dev/virtual/virtio/balloon/Makefile @@ -1,5 +1,5 @@ # -# $FreeBSD$ +# $FreeBSD: head/sys/modules/virtio/balloon/Makefile 314651 2017-03-04 10:10:17Z ngie $ # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions @@ -23,6 +23,11 @@ # SUCH DAMAGE. # -SUBDIR= virtio pci block net random scsi +KMOD= virtio_balloon +SRCS= virtio_balloon.c +SRCS+= virtio_bus_if.h +SRCS+= bus_if.h device_if.h -.include +#KCFLAGS+= -DINVARIANTS -DDEBUG + +.include diff --git a/sys/dev/virtual/virtio/balloon/virtio_balloon.c b/sys/dev/virtual/virtio/balloon/virtio_balloon.c new file mode 100644 index 0000000000..8d5759d25a --- /dev/null +++ b/sys/dev/virtual/virtio/balloon/virtio_balloon.c @@ -0,0 +1,916 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD + * + * Copyright (c) 2011, Bryan Venteicher + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * $FreeBSD: head/sys/dev/virtio/balloon/virtio_balloon.c 326255 2017-11-27 14:52:40Z pfg $ + */ + +/* + * Copyright (c) 2018 The DragonFly Project. All rights reserved. + * + * This code is derived from software contributed to The DragonFly Project + * by Diederik de Groot + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name of The DragonFly Project nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific, prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* Driver for VirtIO memory balloon devices. */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include +#include +#include + +struct vtballoon_softc { + device_t vtballoon_dev; + struct lwkt_serialize vtballoon_slz; + uint64_t vtballoon_features; + uint32_t vtballoon_flags; +#define VTBALLOON_FLAG_DETACH 0x01 + + struct virtqueue *vtballoon_inflate_vq; + struct virtqueue *vtballoon_deflate_vq; + + uint32_t vtballoon_desired_npages; + uint32_t vtballoon_current_npages; + TAILQ_HEAD(,vm_page) vtballoon_pages; + + struct thread *vtballoon_td; + uint32_t *vtballoon_page_frames; + int vtballoon_pagereq; + int vtballoon_timeout; + int vtballoon_nintr; + int vtballoon_debug; +#define VTBALLOON_INFO 0x01 +#define VTBALLOON_ERROR 0x02 +#define VTBALLOON_DEBUG 0x04 +#define VTBALLOON_TRACE 0x08 + + struct virtqueue *vtballoon_stats_vq; + struct vtballoon_stat vtballoon_stats[VTBALLOON_S_NR]; + bool vtballoon_update_stats; +}; + +static struct virtio_feature_desc vtballoon_feature_desc[] = { + { VIRTIO_BALLOON_F_MUST_TELL_HOST, "MustTellHost" }, + { VIRTIO_BALLOON_F_STATS_VQ, "StatsVq" }, + { VIRTIO_BALLOON_F_DEFLATE_ON_OOM, "DeflateOnOutOfMemory" }, + { 0, NULL } +}; + +#define vtballoon_dprintf(_sc, _level, _msg, _args ...) do { \ + if ((_sc)->vtballoon_debug & (_level)) \ + device_printf((_sc)->vtballoon_dev, "%s:%d: "_msg, \ + __FUNCTION__, __LINE__, ##_args); \ +} while (0) + +static int vtballoon_probe(device_t); +static int vtballoon_attach(device_t); +static int vtballoon_detach(device_t); + +static int vtballoon_alloc_intrs(struct vtballoon_softc *sc); + +static void vtballoon_negotiate_features(struct vtballoon_softc *); +static int vtballoon_alloc_virtqueues(struct vtballoon_softc *); + +static void vtballoon_config_change_intr(void *); + +static void vtballoon_update_stats(struct vtballoon_softc *sc); +static void vtballoon_stats_vq_intr(void *); + +static void vtballoon_inflate_vq_intr(void *); +static void vtballoon_deflate_vq_intr(void *); +static void vtballoon_inflate(struct vtballoon_softc *, int); +static void vtballoon_deflate(struct vtballoon_softc *, int); + +static void vtballoon_send_page_frames(struct vtballoon_softc *, + struct virtqueue *, int); + +static void vtballoon_pop(struct vtballoon_softc *); +static void vtballoon_stop(struct vtballoon_softc *); + +static vm_page_t vtballoon_alloc_page(struct vtballoon_softc *); +static void vtballoon_free_page(struct vtballoon_softc *, vm_page_t); + +static int vtballoon_sleep(struct vtballoon_softc *); +static void vtballoon_thread(void *); +static void vtballoon_get_tunables(struct vtballoon_softc *); +static void vtballoon_add_sysctl(struct vtballoon_softc *); + +/* + * Features desired/implemented by this driver. + * VIRTIO_BALLOON_F_STATS_VQ | VIRTIO_BALLOON_F_MUST_TELL_HOST + */ +#define VTBALLOON_FEATURES VIRTIO_BALLOON_F_STATS_VQ + +/* Timeout between retries when the balloon needs inflating. */ +#define VTBALLOON_LOWMEM_TIMEOUT hz * 100 + +/* vm_page_alloc flags */ +#define VTBALLOON_REGULAR_ALLOC VM_ALLOC_NORMAL +#define VTBALLOON_LOWMEM_ALLOC VM_ALLOC_SYSTEM + +/* + * Maximum number of pages we'll request to inflate or deflate + * the balloon in one virtqueue request. Both Linux and NetBSD + * have settled on 256, doing up to 1MB at a time. + */ +#define VTBALLOON_PAGES_PER_REQUEST 256 + +/* + * Default Debug Level + * VTBALLOON_INFO | VTBALLOON_ERROR | VTBALLOON_DEBUG | VTBALLOON_TRACE + */ +#define VTBALLOON_DEFAULT_DEBUG_LEVEL VTBALLOON_INFO | VTBALLOON_ERROR + +/* + * Maximum number of interrupts to request + */ +#define VTBALLOON_MAX_INTERRUPTS 4 + +/* Must be able to fix all pages frames in one page (segment). */ +CTASSERT(VTBALLOON_PAGES_PER_REQUEST * sizeof(uint32_t) <= PAGE_SIZE); + +#define VTBALLOON_SLZ(_sc) &(_sc)->vtballoon_slz +#define VTBALLOON_ENTER_SLZ(_sc) lwkt_serialize_enter(VTBALLOON_SLZ(sc)); +#define VTBALLOON_EXIT_SLZ(_sc) lwkt_serialize_exit(VTBALLOON_SLZ(sc)); + +static device_method_t vtballoon_methods[] = { + /* Device methods. */ + DEVMETHOD(device_probe, vtballoon_probe), + DEVMETHOD(device_attach, vtballoon_attach), + DEVMETHOD(device_detach, vtballoon_detach), + + DEVMETHOD_END +}; + +static driver_t vtballoon_driver = { + "vtballoon", + vtballoon_methods, + sizeof(struct vtballoon_softc) +}; +static devclass_t vtballoon_devclass; + +DRIVER_MODULE(virtio_balloon, virtio_pci, vtballoon_driver, + vtballoon_devclass, 0, 0); +MODULE_VERSION(virtio_balloon, 1); +MODULE_DEPEND(virtio_balloon, virtio, 1, 1, 1); + +static int +vtballoon_probe(device_t dev) +{ + struct vtballoon_softc *sc = device_get_softc(dev); + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + if (virtio_get_device_type(dev) != VIRTIO_ID_BALLOON) + return (ENXIO); + + device_set_desc(dev, "VirtIO Balloon Adapter"); + + return (BUS_PROBE_DEFAULT); +} + +struct irqmap { + int irq; + int idx; + driver_intr_t *handler; + const char * handler_name; +}; + +static int +vtballoon_attach(device_t dev) +{ + struct vtballoon_softc *sc; + int error, i; + + sc = device_get_softc(dev); + sc->vtballoon_dev = dev; + sc->vtballoon_debug = VTBALLOON_DEFAULT_DEBUG_LEVEL; + + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + + lwkt_serialize_init(VTBALLOON_SLZ(sc)); + TAILQ_INIT(&sc->vtballoon_pages); + + vtballoon_get_tunables(sc); + vtballoon_add_sysctl(sc); + + virtio_set_feature_desc(dev, vtballoon_feature_desc); + vtballoon_negotiate_features(sc); + + sc->vtballoon_page_frames = contigmalloc(VTBALLOON_PAGES_PER_REQUEST * + sizeof(uint32_t), M_DEVBUF, M_NOWAIT | M_ZERO, 0, BUS_SPACE_MAXADDR, 16, 0); + if (sc->vtballoon_page_frames == NULL) { + error = ENOMEM; + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot allocate page frame request array (error:%d)\n", error); + goto fail; + } + error = vtballoon_alloc_intrs(sc); + if (error) { + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot allocate interrupts (error:%d)\n", error); + goto fail; + } + + error = vtballoon_alloc_virtqueues(sc); + if (error) { + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot allocate virtqueues (error:%d)\n", error); + goto fail; + } + + int nrhandlers = virtio_with_feature(sc->vtballoon_dev, VIRTIO_BALLOON_F_STATS_VQ) ? 4 : 3; + struct irqmap info[4]; + + /* Possible "Virtqueue <-> IRQ" configurations */ + switch (sc->vtballoon_nintr) { + case 1: + info[2] = (struct irqmap){0, -1, vtballoon_config_change_intr, "config"}; + info[0] = (struct irqmap){0, 0, vtballoon_inflate_vq_intr, "inflate"}; + info[1] = (struct irqmap){0, 1, vtballoon_deflate_vq_intr, "deflate"}; + info[3] = (struct irqmap){0, 2, vtballoon_stats_vq_intr, "stats"}; + break; + case 2: + info[2] = (struct irqmap){1, -1, vtballoon_config_change_intr, "config"}; + info[0] = (struct irqmap){0, 0, vtballoon_inflate_vq_intr, "inflate"}; + info[1] = (struct irqmap){0, 1, vtballoon_deflate_vq_intr, "deflate"}; + info[3] = (struct irqmap){0, 2, vtballoon_stats_vq_intr, "stats"}; + break; + case 3: + info[2] = (struct irqmap){2, -1, vtballoon_config_change_intr, "config"}; + info[0] = (struct irqmap){0, 0, vtballoon_inflate_vq_intr, "inflate"}; + info[1] = (struct irqmap){1, 1, vtballoon_deflate_vq_intr, "deflate"}; + info[3] = (struct irqmap){2, 2, vtballoon_stats_vq_intr, "stats"}; + break; + case 4: + info[2] = (struct irqmap){3, -1, vtballoon_config_change_intr, "config"}; + info[0] = (struct irqmap){0, 0, vtballoon_inflate_vq_intr, "inflate"}; + info[1] = (struct irqmap){1, 1, vtballoon_deflate_vq_intr, "deflate"}; + info[3] = (struct irqmap){2, 2, vtballoon_stats_vq_intr, "stats"}; + break; + default: + vtballoon_dprintf(sc, VTBALLOON_ERROR, "Invalid interrupt vector count: %d\n", sc->vtballoon_nintr); + goto fail; + } + for (i = 0; i < nrhandlers; i++) { + error = virtio_bind_intr(sc->vtballoon_dev, info[i].irq, info[i].idx, + info[i].handler, sc); + if (error) { + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot bind virtqueue '%s' handler to IRQ:%d/%d\n", + info[i].handler_name, info[i].irq, sc->vtballoon_nintr); + goto fail; + } + } + + for (i = 0; i < sc->vtballoon_nintr; i++) { + error = virtio_setup_intr(dev, i, VTBALLOON_SLZ(sc)); + if (error) { + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot setup virtqueue interrupt:%d (error:%d)\n", i, error); + goto fail; + } + } + + error = kthread_create(vtballoon_thread, sc, &sc->vtballoon_td, "virtio_balloon"); + if (error) { + vtballoon_dprintf(sc, VTBALLOON_ERROR, "cannot create balloon kthread (error:%d)\n", error); + goto fail; + } + + virtqueue_enable_intr(sc->vtballoon_inflate_vq); + virtqueue_enable_intr(sc->vtballoon_deflate_vq); + + if (virtio_with_feature(sc->vtballoon_dev, VIRTIO_BALLOON_F_STATS_VQ)) { + virtqueue_enable_intr(sc->vtballoon_stats_vq); +#if 0 /* enabling this causes a panic, on asserting ASSERT_SERIALIZED(sc) in vtballoon_update_stats */ + /* + * Prime this stats virtqueue with one buffer so the hypervisor can + * use it to signal us later. + */ + VTBALLOON_ENTER_SLZ(sc); + vtballoon_update_stats(sc); + VTBALLOON_EXIT_SLZ(sc); +#endif + } + +fail: + if (error) + vtballoon_detach(dev); + + return (error); +} + +static int +vtballoon_detach(device_t dev) +{ + struct vtballoon_softc *sc; + int i; + + sc = device_get_softc(dev); + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + + if (sc->vtballoon_td != NULL) { + VTBALLOON_ENTER_SLZ(sc); + sc->vtballoon_flags |= VTBALLOON_FLAG_DETACH; + + /* drain */ + wakeup_one(sc); + zsleep(sc->vtballoon_td, VTBALLOON_SLZ(sc), 0, "vtbdth", 0); + VTBALLOON_EXIT_SLZ(sc); + sc->vtballoon_td = NULL; + } + + lwkt_serialize_handler_disable(VTBALLOON_SLZ(sc)); + + for (i = 0; i < sc->vtballoon_nintr; i++) + virtio_teardown_intr(dev, i); + + if (device_is_attached(dev)) { + vtballoon_pop(sc); + vtballoon_stop(sc); + } + + if (sc->vtballoon_page_frames != NULL) { + contigfree(sc->vtballoon_page_frames, VTBALLOON_PAGES_PER_REQUEST * + sizeof(uint32_t), M_DEVBUF); + sc->vtballoon_page_frames = NULL; + } + return (0); +} + +static void +vtballoon_negotiate_features(struct vtballoon_softc *sc) +{ + device_t dev; + uint64_t features; + + dev = sc->vtballoon_dev; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + features = virtio_negotiate_features(dev, VTBALLOON_FEATURES); + sc->vtballoon_features = features; +} + +static int vtballoon_alloc_intrs(struct vtballoon_softc *sc) +{ + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + int cnt, error; + int intrcount = virtio_intr_count(sc->vtballoon_dev); + int use_config = 1; + + intrcount = imin(intrcount, VTBALLOON_MAX_INTERRUPTS); + if (intrcount < 1) + return (ENXIO); + + cnt = intrcount; + error = virtio_intr_alloc(sc->vtballoon_dev, &cnt, use_config, NULL); + if (error != 0) { + virtio_intr_release(sc->vtballoon_dev); + return (error); + } + sc->vtballoon_nintr = cnt; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "%d Interrupts Allocated\n", sc->vtballoon_nintr); + return (0); +} + +static int +vtballoon_alloc_virtqueues(struct vtballoon_softc *sc) +{ + device_t dev; + struct vq_alloc_info vq_info[3]; + int nvqs; + + dev = sc->vtballoon_dev; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + nvqs = 2; + + VQ_ALLOC_INFO_INIT(&vq_info[0], 0, &sc->vtballoon_inflate_vq, + "%s inflate", device_get_nameunit(dev)); + + VQ_ALLOC_INFO_INIT(&vq_info[1], 0, &sc->vtballoon_deflate_vq, + "%s deflate", device_get_nameunit(dev)); + + if (virtio_with_feature(sc->vtballoon_dev, VIRTIO_BALLOON_F_STATS_VQ)) { + VQ_ALLOC_INFO_INIT(&vq_info[2], 0, &sc->vtballoon_stats_vq, + "%s stats", device_get_nameunit(dev)); + nvqs = 3; + } + return (virtio_alloc_virtqueues(dev, nvqs, vq_info)); +} + +static void +vtballoon_config_change_intr(void *arg) +{ + struct vtballoon_softc *sc = arg; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + ASSERT_SERIALIZED(VTBALLOON_SLZ(sc)); + wakeup_one(sc); +} + +static inline void +vtballoon_update_stat(struct vtballoon_softc *sc, int idx, + uint16_t tag, uint64_t val) +{ + KASSERT(idx >= VTBALLOON_S_NR, ("Stats index out of bounds")); + /* + * XXX: Required for endianess in the future + * sc->vtballoon_stats[idx].tag = virtio_is_little_endian(sc->vtballoon_dev) ? le16toh(tag) : tag; + * sc->vtballoon_stats[idx].val = virtio_is_little_endian(sc->vtballoon_dev) ? le64toh(val) : val; + * at the moment virtio balloon is always little endian. + * + */ + sc->vtballoon_stats[idx].tag = le16toh(tag); + sc->vtballoon_stats[idx].val = le64toh(val); + +} + +/* + * collect guest side statistics + * + * XXX: am i using the correct memory and pagefault values + */ +static unsigned int collect_balloon_stats(struct vtballoon_softc *sc) +{ + #define pages_to_bytes(x) ((uint64_t)(x) << PAGE_SHIFT) + unsigned int idx = 0; + struct vmtotal total; + struct vmmeter vmm; + struct vmstats vms; + size_t vmt_size = sizeof(total); + size_t vmm_size = sizeof(vmm); + size_t vms_size = sizeof(vms); + + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Updating Stats Buffer\n"); + if (!kernel_sysctlbyname("vm.vmtotal", &total, &vmt_size, NULL, 0, NULL)) { + /* Total amount of free memory )*/ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_MEMFREE, + pages_to_bytes(total.t_rm - total.t_arm)); + /* Total amount of memory */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_MEMTOT, + pages_to_bytes(total.t_rm)); + /* Available memory as in /proc */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_AVAIL, + pages_to_bytes(total.t_arm)); + } + if (!kernel_sysctlbyname("vm.vmstats", &vms, &vms_size, NULL, 0, NULL)) { + /* Disk caches */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_CACHES, + pages_to_bytes(vms.v_cache_count)); + } + if (!kernel_sysctlbyname("vm.vmmeter", &vmm, &vmm_size, NULL, 0, NULL)) { + /* Amount of memory swapped in */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_SWAP_IN, + pages_to_bytes(vmm.v_swappgsin)); + /* Amount of memory swapped out */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_SWAP_OUT, + pages_to_bytes(vmm.v_swappgsout)); + /* Number of major faults */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_MAJFLT, + vmm.v_vm_faults); + /* Number of minor faults */ + vtballoon_update_stat(sc, idx++, VTBALLOON_S_MINFLT, + vmm.v_intrans); + } + + if (sc->vtballoon_debug & VTBALLOON_TRACE) { + static const char *vt_balloon_names[]=VTBALLOON_S_NAMES; + int i; + for (i=0; i < idx; i++) { + kprintf("\t%s = %lu\n", vt_balloon_names[sc->vtballoon_stats[i].tag], sc->vtballoon_stats[i].val); + } + } + + return idx; +} + +static void +vtballoon_update_stats(struct vtballoon_softc *sc) +{ + struct virtqueue *vq = sc->vtballoon_stats_vq; + + ASSERT_SERIALIZED(VTBALLOON_SLZ(sc)); + + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Stats Requested\n"); + + struct sglist sg; + struct sglist_seg segs[1]; + unsigned int num_stats; + int error; + + num_stats = collect_balloon_stats(sc); + + sglist_init(&sg, 1, segs); + error = sglist_append(&sg, sc->vtballoon_stats, sizeof(sc->vtballoon_stats[0]) * num_stats); + KASSERT(error == 0, ("error adding page frames to sglist")); + + error = virtqueue_enqueue(vq, vq, &sg, 1, 0); + KASSERT(error == 0, ("error enqueuing page frames to virtqueue")); + virtqueue_notify(sc->vtballoon_stats_vq, NULL); +} + +/* + * While most virtqueues communicate guest-initiated requests to the hypervisor, + * the stats queue operates in reverse. The driver(host) initializes the virtqueue + * with a single buffer. From that point forward, all conversations consist of + * a hypervisor request (a call to this function) which directs us to refill + * the virtqueue with a fresh stats buffer. Since stats collection can sleep, + * we delegate the job to the vtballoon_thread which will do the actual stats + * collecting work. + */ +static void +vtballoon_stats_vq_intr(void *arg) +{ + struct vtballoon_softc *sc = arg; + struct virtqueue *vq = sc->vtballoon_stats_vq; + + ASSERT_SERIALIZED(VTBALLOON_SLZ(sc)); + if (sc->vtballoon_update_stats || !virtqueue_pending(vq)) + return; + + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Ballooon Stats Requested\n"); + sc->vtballoon_update_stats = true; + wakeup_one(sc); + virtqueue_dequeue(vq, NULL); +} + +static void +vtballoon_inflate_vq_intr(void *arg) +{ + struct vtballoon_softc *sc = arg; + struct virtqueue *vq = sc->vtballoon_inflate_vq; + ASSERT_SERIALIZED(VTBALLOON_SLZ(sc)); + if (!virtqueue_pending(vq)) + return; + wakeup_one(sc); +} + +static void +vtballoon_deflate_vq_intr(void *arg) +{ + struct vtballoon_softc *sc = arg; + struct virtqueue *vq = sc->vtballoon_deflate_vq; + ASSERT_SERIALIZED(VTBALLOON_SLZ(sc)); + if (!virtqueue_pending(vq)) + return; + wakeup_one(sc); +} + +static void +vtballoon_inflate(struct vtballoon_softc *sc, int npages) +{ + struct virtqueue *vq; + + vm_page_t m; + int i; + + vq = sc->vtballoon_inflate_vq; + + if (npages > VTBALLOON_PAGES_PER_REQUEST) + npages = VTBALLOON_PAGES_PER_REQUEST; + + for (i = 0; i < npages; i++) { + if ((m = vtballoon_alloc_page(sc)) == NULL) { + /* First allocate usign VTBALLOON_REGULAR_ALLOC and fall back to VTBALLOON_LOWMEM_ALLOC + * when the guest is under severe memory pressure. Quickly decrease the + * allocation rate, allowing the system to swap out pages. + */ + sc->vtballoon_pagereq = VM_ALLOC_SYSTEM | VM_ALLOC_INTERRUPT; + sc->vtballoon_timeout = VTBALLOON_LOWMEM_TIMEOUT; + break; + } + + sc->vtballoon_page_frames[i] = + VM_PAGE_TO_PHYS(m) >> VIRTIO_BALLOON_PFN_SHIFT; + + KASSERT(m->queue == PQ_NONE, + ("%s: allocated page %p on queue", __func__, m)); + TAILQ_INSERT_TAIL(&sc->vtballoon_pages, m, pageq); + } + + if (i > 0) + vtballoon_send_page_frames(sc, vq, i); +} + +static void +vtballoon_deflate(struct vtballoon_softc *sc, int npages) +{ + TAILQ_HEAD(, vm_page) free_pages; + struct virtqueue *vq; + vm_page_t m; + int i; + + vq = sc->vtballoon_deflate_vq; + TAILQ_INIT(&free_pages); + + if (npages > VTBALLOON_PAGES_PER_REQUEST) + npages = VTBALLOON_PAGES_PER_REQUEST; + + for (i = 0; i < npages; i++) { + m = TAILQ_FIRST(&sc->vtballoon_pages); + KASSERT(m != NULL, ("%s: no more pages to deflate", __func__)); + + sc->vtballoon_page_frames[i] = + VM_PAGE_TO_PHYS(m) >> VIRTIO_BALLOON_PFN_SHIFT; + + TAILQ_REMOVE(&sc->vtballoon_pages, m, pageq); + TAILQ_INSERT_TAIL(&free_pages, m, pageq); + } + + if (i > 0) { + /* + * Note that if virtio VIRTIO_BALLOON_F_MUST_TELL_HOST + * feature is true, we *have* to tell host first + * before freeing the pages. + */ + vtballoon_send_page_frames(sc, vq, i); + + while ((m = TAILQ_FIRST(&free_pages)) != NULL) { + TAILQ_REMOVE(&free_pages, m, pageq); + vtballoon_free_page(sc, m); + } + } + + KASSERT((TAILQ_EMPTY(&sc->vtballoon_pages) && + sc->vtballoon_current_npages == 0) || + (!TAILQ_EMPTY(&sc->vtballoon_pages) && + sc->vtballoon_current_npages != 0), + ("%s: bogus page count %d", __func__, + sc->vtballoon_current_npages)); +} + +static void +vtballoon_send_page_frames(struct vtballoon_softc *sc, struct virtqueue *vq, + int npages) +{ + struct sglist sg; + struct sglist_seg segs[1]; + void *c; + int error; + + sglist_init(&sg, 1, segs); + + error = sglist_append(&sg, sc->vtballoon_page_frames, + npages * sizeof(uint32_t)); + KASSERT(error == 0, ("error adding page frames to sglist")); + + error = virtqueue_enqueue(vq, vq, &sg, 1, 0); + KASSERT(error == 0, ("error enqueuing page frames to virtqueue")); + virtqueue_notify(vq, NULL); + + /* + * Inflate and deflate operations are done synchronously. The + * interrupt handler will wake us up. + */ + VTBALLOON_ENTER_SLZ(sc); + while ((c = virtqueue_dequeue(vq, NULL)) == NULL) { + zsleep(sc, VTBALLOON_SLZ(sc), 0, "vtbspf", 0); + } + VTBALLOON_EXIT_SLZ(sc); + + KASSERT(c == vq, ("unexpected balloon operation response")); +} + +static void +vtballoon_pop(struct vtballoon_softc *sc) +{ + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Popping\n"); + + while (!TAILQ_EMPTY(&sc->vtballoon_pages)) + vtballoon_deflate(sc, sc->vtballoon_current_npages); +} + +static void +vtballoon_stop(struct vtballoon_softc *sc) +{ + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Stopping\n"); + + virtqueue_disable_intr(sc->vtballoon_inflate_vq); + virtqueue_disable_intr(sc->vtballoon_deflate_vq); +/* + if (virtio_with_feature(sc->vtballoon_dev, VIRTIO_BALLOON_F_STATS_VQ)) { + virtqueue_disable_intr(sc->vtballoon_stats_vq); + } +*/ + virtio_stop(sc->vtballoon_dev); +} + +static vm_page_t +vtballoon_alloc_page(struct vtballoon_softc *sc) +{ + vm_page_t m; + + m = vm_page_alloc(NULL, 0, sc->vtballoon_pagereq); + if (m != NULL) + sc->vtballoon_current_npages++; + + return (m); +} + +static void +vtballoon_free_page(struct vtballoon_softc *sc, vm_page_t m) +{ + vm_page_free_toq(m); + sc->vtballoon_current_npages--; +} + +static uint32_t +vtballoon_desired_size(struct vtballoon_softc *sc) +{ + uint32_t desired; + + desired = virtio_read_dev_config_4(sc->vtballoon_dev, + offsetof(struct virtio_balloon_config, num_pages)); + + return (le32toh(desired)); +} + +static void +vtballoon_update_size(struct vtballoon_softc *sc) +{ + virtio_write_dev_config_4(sc->vtballoon_dev, + offsetof(struct virtio_balloon_config, actual), + htole32(sc->vtballoon_current_npages)); +} + +static int +vtballoon_sleep(struct vtballoon_softc *sc) +{ + int rc, timeout; + uint32_t current, desired; + + rc = 0; + current = sc->vtballoon_current_npages; + sc->vtballoon_pagereq = VM_ALLOC_NORMAL | VM_ALLOC_INTERRUPT; + + VTBALLOON_ENTER_SLZ(sc); + for (;;) { + if (sc->vtballoon_flags & VTBALLOON_FLAG_DETACH) { + rc = 1; + break; + } + + desired = vtballoon_desired_size(sc); + if (desired != sc->vtballoon_desired_npages) + vtballoon_dprintf(sc, VTBALLOON_DEBUG, "balloon %s %d -> %d (4K pages)\n", + desired < sc->vtballoon_desired_npages ? "deflating" : "inflating", + current, desired); + + sc->vtballoon_desired_npages = desired; + + /* + * If given, use non-zero timeout on the first time through + * the loop. On subsequent times, timeout will be zero so + * we will reevaluate the desired size of the balloon and + * break out to retry if needed. + */ + timeout = sc->vtballoon_timeout; + sc->vtballoon_timeout = 0; + + if (current > desired) + break; + else if (current < desired && timeout == 0) + break; + else if (sc->vtballoon_update_stats) + break; + else if (!timeout) + vtballoon_dprintf(sc, VTBALLOON_TRACE, "balloon %d (4K pages) reached\n", current); + + zsleep(sc, VTBALLOON_SLZ(sc), 0, "vtbslp", timeout); + } + VTBALLOON_EXIT_SLZ(sc); + + return (rc); +} + +static void +vtballoon_thread(void *arg) +{ + struct vtballoon_softc *sc = arg; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "Thread started.\n"); + + uint32_t current, desired; + for (;;) { + if (vtballoon_sleep(sc) != 0) + break; + + current = sc->vtballoon_current_npages; + desired = sc->vtballoon_desired_npages; + + if (desired != current) { + if (desired > current) + vtballoon_inflate(sc, desired - current); + else + vtballoon_deflate(sc, current - desired); + + vtballoon_update_size(sc); + } + if (sc->vtballoon_update_stats) { + vtballoon_update_stats(sc); + sc->vtballoon_update_stats = false; + } + } + + kthread_exit(); +} + +static void +vtballoon_get_tunables(struct vtballoon_softc *sc) +{ + char tmpstr[64]; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + + TUNABLE_INT_FETCH("hw.vtballoon.debug_level", &sc->vtballoon_debug); + + ksnprintf(tmpstr, sizeof(tmpstr), "dev.vtballoon.%d.debug_level", + device_get_unit(sc->vtballoon_dev)); + TUNABLE_INT_FETCH(tmpstr, &sc->vtballoon_debug); +} + +static void +vtballoon_add_sysctl(struct vtballoon_softc *sc) +{ + device_t dev; + struct sysctl_ctx_list *ctx; + struct sysctl_oid *tree; + struct sysctl_oid_list *child; + + dev = sc->vtballoon_dev; + vtballoon_dprintf(sc, VTBALLOON_TRACE, "\n"); + + ctx = device_get_sysctl_ctx(dev); + tree = device_get_sysctl_tree(dev); + child = SYSCTL_CHILDREN(tree); + + SYSCTL_ADD_INT(ctx, child, OID_AUTO, "debug_level", + CTLFLAG_RW, &sc->vtballoon_debug, 0, + "Debug level"); + + SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "desired", + CTLFLAG_RD, &sc->vtballoon_desired_npages, sizeof(uint32_t), + "Desired balloon size in pages"); + + SYSCTL_ADD_UINT(ctx, child, OID_AUTO, "current", + CTLFLAG_RD, &sc->vtballoon_current_npages, sizeof(uint32_t), + "Current balloon size in pages"); +} diff --git a/sys/dev/virtual/virtio/balloon/virtio_balloon.h b/sys/dev/virtual/virtio/balloon/virtio_balloon.h new file mode 100644 index 0000000000..4970998f07 --- /dev/null +++ b/sys/dev/virtual/virtio/balloon/virtio_balloon.h @@ -0,0 +1,126 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of IBM nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED + * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD: head/sys/dev/virtio/balloon/virtio_balloon.h 326022 2017-11-20 19:36:21Z pfg $ + */ +/* + * Copyright (c) 2018 The DragonFly Project. All rights reserved. + * + * This code is derived from software contributed to The DragonFly Project + * by Diederik de Groot + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name of The DragonFly Project nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific, prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/* Driver for VirtIO memory balloon devices. */ + +#ifndef _VIRTIO_BALLOON_H +#define _VIRTIO_BALLOON_H + +/* Feature bits. */ +#define VIRTIO_BALLOON_F_MUST_TELL_HOST 0x1 /* Tell before reclaiming pages */ +#define VIRTIO_BALLOON_F_STATS_VQ 0x2 /* Memory stats virtqueue */ +#define VIRTIO_BALLOON_F_DEFLATE_ON_OOM 0x3 /* Deflate on Out Of Memory */ + +/* Size of a PFN in the balloon interface. */ +#define VIRTIO_BALLOON_PFN_SHIFT 12 + +struct virtio_balloon_config { + /* Number of pages host wants Guest to give up. */ + uint32_t num_pages; + + /* Number of pages we've actually got in balloon. */ + uint32_t actual; +}; + +#define VTBALLOON_S_SWAP_IN 0 /* The amount of memory that has been swapped in (in bytes) */ +#define VTBALLOON_S_SWAP_OUT 1 /* The amount of memory that has been swapped out to disk (in bytes). */ +#define VTBALLOON_S_MAJFLT 2 /* The number of major page faults that have occurred. */ +#define VTBALLOON_S_MINFLT 3 /* The number of minor page faults that have occurred. */ +#define VTBALLOON_S_MEMFREE 4 /* The amount of memory not being used for any purpose (in bytes). */ +#define VTBALLOON_S_MEMTOT 5 /* The total amount of memory available (in bytes). */ +#define VTBALLOON_S_AVAIL 6 /* The amount of availabe memory (in bytes) as in linux-proc */ +#define VTBALLOON_S_CACHES 7 /* Disk-File caches */ +#define VTBALLOON_S_HTLB_PGALLOC 8 /* Hugetlb page allocations */ +#define VTBALLOON_S_HTLB_PGFAIL 9 /* Hugetlb page allocation failures */ +#define VTBALLOON_S_NR 10 + +#define VTBALLOON_S_NAMES_WITH_PREFIX(VTBALLOON_S_NAMES_prefix) { \ + VTBALLOON_S_NAMES_prefix "swap-in", \ + VTBALLOON_S_NAMES_prefix "swap-out", \ + VTBALLOON_S_NAMES_prefix "major-faults", \ + VTBALLOON_S_NAMES_prefix "minor-faults", \ + VTBALLOON_S_NAMES_prefix "free-memory", \ + VTBALLOON_S_NAMES_prefix "total-memory", \ + VTBALLOON_S_NAMES_prefix "available-memory", \ + VTBALLOON_S_NAMES_prefix "disk-file-caches", \ + VTBALLOON_S_NAMES_prefix "hugetlb-allocations", \ + VTBALLOON_S_NAMES_prefix "hugetlb-failures" \ +} +#define VTBALLOON_S_NAMES VTBALLOON_S_NAMES_WITH_PREFIX("") + +/* + * Memory statistics structure. + * Driver fills an array of these structures and passes to device. + * + * NOTE: fields are laid out in a way that would make compiler add padding + * between and after fields, but the virtio specification does not allow + * for this. So the struct has to be packed. + */ +struct vtballoon_stat { + uint16_t tag; + uint64_t val; +} __packed; + +#endif /* _VIRTIO_BALLOON_H */