diff --git a/sys/dev/virtio/balloon/virtio_balloon.c b/sys/dev/virtio/balloon/virtio_balloon.c index 2292ca384ba9..0973528887c5 100644 --- a/sys/dev/virtio/balloon/virtio_balloon.c +++ b/sys/dev/virtio/balloon/virtio_balloon.c @@ -1,566 +1,581 @@ /*- * 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. */ /* Driver for VirtIO memory balloon devices. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "virtio_if.h" struct vtballoon_softc { device_t vtballoon_dev; struct mtx vtballoon_mtx; 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_timeout; }; 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, "DeflateOnOOM" }, + { 0, NULL } }; static int vtballoon_probe(device_t); static int vtballoon_attach(device_t); static int vtballoon_detach(device_t); static int vtballoon_config_change(device_t); static void vtballoon_negotiate_features(struct vtballoon_softc *); static int vtballoon_alloc_virtqueues(struct vtballoon_softc *); static void vtballoon_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_add_sysctl(struct vtballoon_softc *); +#define vtballoon_modern(_sc) \ + (((_sc)->vtballoon_features & VIRTIO_F_VERSION_1) != 0) + /* Features desired/implemented by this driver. */ -#define VTBALLOON_FEATURES 0 +#define VTBALLOON_FEATURES VIRTIO_BALLOON_F_MUST_TELL_HOST /* Timeout between retries when the balloon needs inflating. */ #define VTBALLOON_LOWMEM_TIMEOUT hz /* * 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 /* Must be able to fix all pages frames in one page (segment). */ CTASSERT(VTBALLOON_PAGES_PER_REQUEST * sizeof(uint32_t) <= PAGE_SIZE); #define VTBALLOON_MTX(_sc) &(_sc)->vtballoon_mtx #define VTBALLOON_LOCK_INIT(_sc, _name) mtx_init(VTBALLOON_MTX((_sc)), _name, \ "VirtIO Balloon Lock", MTX_DEF) #define VTBALLOON_LOCK(_sc) mtx_lock(VTBALLOON_MTX((_sc))) #define VTBALLOON_UNLOCK(_sc) mtx_unlock(VTBALLOON_MTX((_sc))) #define VTBALLOON_LOCK_DESTROY(_sc) mtx_destroy(VTBALLOON_MTX((_sc))) static device_method_t vtballoon_methods[] = { /* Device methods. */ DEVMETHOD(device_probe, vtballoon_probe), DEVMETHOD(device_attach, vtballoon_attach), DEVMETHOD(device_detach, vtballoon_detach), /* VirtIO methods. */ DEVMETHOD(virtio_config_change, vtballoon_config_change), DEVMETHOD_END }; static driver_t vtballoon_driver = { "vtballoon", vtballoon_methods, sizeof(struct vtballoon_softc) }; static devclass_t vtballoon_devclass; DRIVER_MODULE(virtio_balloon, virtio_mmio, vtballoon_driver, vtballoon_devclass, 0, 0); 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); VIRTIO_SIMPLE_PNPTABLE(virtio_balloon, VIRTIO_ID_BALLOON, "VirtIO Balloon Adapter"); VIRTIO_SIMPLE_PNPINFO(virtio_mmio, virtio_balloon); VIRTIO_SIMPLE_PNPINFO(virtio_pci, virtio_balloon); static int vtballoon_probe(device_t dev) { return (VIRTIO_SIMPLE_PROBE(dev, virtio_balloon)); } static int vtballoon_attach(device_t dev) { struct vtballoon_softc *sc; int error; sc = device_get_softc(dev); sc->vtballoon_dev = dev; VTBALLOON_LOCK_INIT(sc, device_get_nameunit(dev)); TAILQ_INIT(&sc->vtballoon_pages); vtballoon_add_sysctl(sc); virtio_set_feature_desc(dev, vtballoon_feature_desc); vtballoon_negotiate_features(sc); sc->vtballoon_page_frames = malloc(VTBALLOON_PAGES_PER_REQUEST * sizeof(uint32_t), M_DEVBUF, M_NOWAIT | M_ZERO); if (sc->vtballoon_page_frames == NULL) { error = ENOMEM; device_printf(dev, "cannot allocate page frame request array\n"); goto fail; } error = vtballoon_alloc_virtqueues(sc); if (error) { device_printf(dev, "cannot allocate virtqueues\n"); goto fail; } error = virtio_setup_intr(dev, INTR_TYPE_MISC); if (error) { device_printf(dev, "cannot setup virtqueue interrupts\n"); goto fail; } error = kthread_add(vtballoon_thread, sc, NULL, &sc->vtballoon_td, 0, 0, "virtio_balloon"); if (error) { device_printf(dev, "cannot create balloon kthread\n"); goto fail; } virtqueue_enable_intr(sc->vtballoon_inflate_vq); virtqueue_enable_intr(sc->vtballoon_deflate_vq); fail: if (error) vtballoon_detach(dev); return (error); } static int vtballoon_detach(device_t dev) { struct vtballoon_softc *sc; sc = device_get_softc(dev); if (sc->vtballoon_td != NULL) { VTBALLOON_LOCK(sc); sc->vtballoon_flags |= VTBALLOON_FLAG_DETACH; wakeup_one(sc); msleep(sc->vtballoon_td, VTBALLOON_MTX(sc), 0, "vtbdth", 0); VTBALLOON_UNLOCK(sc); sc->vtballoon_td = NULL; } if (device_is_attached(dev)) { vtballoon_pop(sc); vtballoon_stop(sc); } if (sc->vtballoon_page_frames != NULL) { free(sc->vtballoon_page_frames, M_DEVBUF); sc->vtballoon_page_frames = NULL; } VTBALLOON_LOCK_DESTROY(sc); return (0); } static int vtballoon_config_change(device_t dev) { struct vtballoon_softc *sc; sc = device_get_softc(dev); VTBALLOON_LOCK(sc); wakeup_one(sc); VTBALLOON_UNLOCK(sc); return (1); } static void vtballoon_negotiate_features(struct vtballoon_softc *sc) { device_t dev; uint64_t features; dev = sc->vtballoon_dev; - features = virtio_negotiate_features(dev, VTBALLOON_FEATURES); - sc->vtballoon_features = features; + features = VTBALLOON_FEATURES; + + sc->vtballoon_features = virtio_negotiate_features(dev, features); + virtio_finalize_features(dev); } static int vtballoon_alloc_virtqueues(struct vtballoon_softc *sc) { device_t dev; struct vq_alloc_info vq_info[2]; int nvqs; dev = sc->vtballoon_dev; nvqs = 2; VQ_ALLOC_INFO_INIT(&vq_info[0], 0, vtballoon_vq_intr, sc, &sc->vtballoon_inflate_vq, "%s inflate", device_get_nameunit(dev)); VQ_ALLOC_INFO_INIT(&vq_info[1], 0, vtballoon_vq_intr, sc, &sc->vtballoon_deflate_vq, "%s deflate", device_get_nameunit(dev)); return (virtio_alloc_virtqueues(dev, 0, nvqs, vq_info)); } static void vtballoon_vq_intr(void *xsc) { struct vtballoon_softc *sc; sc = xsc; VTBALLOON_LOCK(sc); wakeup_one(sc); VTBALLOON_UNLOCK(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) { sc->vtballoon_timeout = VTBALLOON_LOWMEM_TIMEOUT; break; } sc->vtballoon_page_frames[i] = VM_PAGE_TO_PHYS(m) >> VIRTIO_BALLOON_PFN_SHIFT; KASSERT(m->a.queue == PQ_NONE, ("%s: allocated page %p on queue", __func__, m)); TAILQ_INSERT_TAIL(&sc->vtballoon_pages, m, plinks.q); } 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, plinks.q); TAILQ_INSERT_TAIL(&free_pages, m, plinks.q); } if (i > 0) { /* Always 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, plinks.q); 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); /* * Inflate and deflate operations are done synchronously. The * interrupt handler will wake us up. */ VTBALLOON_LOCK(sc); while ((c = virtqueue_dequeue(vq, NULL)) == NULL) msleep(sc, VTBALLOON_MTX(sc), 0, "vtbspf", 0); VTBALLOON_UNLOCK(sc); KASSERT(c == vq, ("unexpected balloon operation response")); } static void vtballoon_pop(struct vtballoon_softc *sc) { while (!TAILQ_EMPTY(&sc->vtballoon_pages)) vtballoon_deflate(sc, sc->vtballoon_current_npages); } static void vtballoon_stop(struct vtballoon_softc *sc) { virtqueue_disable_intr(sc->vtballoon_inflate_vq); virtqueue_disable_intr(sc->vtballoon_deflate_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, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ); + m = vm_page_alloc(NULL, 0, + VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ | VM_ALLOC_NODUMP); 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(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)); + if (vtballoon_modern(sc)) + return (desired); + else + return (le32toh(desired)); } static void vtballoon_update_size(struct vtballoon_softc *sc) { + uint32_t npages; + + npages = sc->vtballoon_current_npages; + if (!vtballoon_modern(sc)) + npages = htole32(npages); virtio_write_dev_config_4(sc->vtballoon_dev, - offsetof(struct virtio_balloon_config, actual), - htole32(sc->vtballoon_current_npages)); + offsetof(struct virtio_balloon_config, actual), npages); } static int vtballoon_sleep(struct vtballoon_softc *sc) { int rc, timeout; uint32_t current, desired; rc = 0; current = sc->vtballoon_current_npages; VTBALLOON_LOCK(sc); for (;;) { if (sc->vtballoon_flags & VTBALLOON_FLAG_DETACH) { rc = 1; break; } desired = vtballoon_desired_size(sc); 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; if (current < desired && timeout == 0) break; msleep(sc, VTBALLOON_MTX(sc), 0, "vtbslp", timeout); } VTBALLOON_UNLOCK(sc); return (rc); } static void vtballoon_thread(void *xsc) { struct vtballoon_softc *sc; uint32_t current, desired; sc = xsc; 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); } } kthread_exit(); } 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; ctx = device_get_sysctl_ctx(dev); tree = device_get_sysctl_tree(dev); child = SYSCTL_CHILDREN(tree); 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/virtio/balloon/virtio_balloon.h b/sys/dev/virtio/balloon/virtio_balloon.h index b871dfb01c56..07802d84ce52 100644 --- a/sys/dev/virtio/balloon/virtio_balloon.h +++ b/sys/dev/virtio/balloon/virtio_balloon.h @@ -1,64 +1,90 @@ /*- * 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. * * $FreeBSD$ */ #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 0x4 /* Deflate balloon on OOM */ /* 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 VIRTIO_BALLOON_S_SWAP_IN 0 /* Amount of memory swapped in */ #define VIRTIO_BALLOON_S_SWAP_OUT 1 /* Amount of memory swapped out */ #define VIRTIO_BALLOON_S_MAJFLT 2 /* Number of major faults */ #define VIRTIO_BALLOON_S_MINFLT 3 /* Number of minor faults */ #define VIRTIO_BALLOON_S_MEMFREE 4 /* Total amount of free memory */ #define VIRTIO_BALLOON_S_MEMTOT 5 /* Total amount of memory */ -#define VIRTIO_BALLOON_S_NR 6 +#define VIRTIO_BALLOON_S_AVAIL 6 /* Available memory as in /proc */ +#define VIRTIO_BALLOON_S_CACHES 7 /* Disk caches */ +#define VIRTIO_BALLOON_S_NR 8 +/* + * 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, so we have to use compiler-specific attributes to + * pack it, to disable this padding. This also often causes compiler to + * generate suboptimal code. + * + * We maintain this statistics structure format for backwards compatibility, + * but don't follow this example. + * + * If implementing a similar structure, do something like the below instead: + * struct virtio_balloon_stat { + * __virtio16 tag; + * __u8 reserved[6]; + * __virtio64 val; + * }; + * + * In other words, add explicit reserved fields to align field and + * structure boundaries at field size, avoiding compiler padding + * without the packed attribute. + */ struct virtio_balloon_stat { uint16_t tag; uint64_t val; } __packed; #endif /* _VIRTIO_BALLOON_H */