diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-06 13:20:13 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-08-06 13:20:13 (GMT) |
commit | 0803e04011c2e107b9611660301edde94d7010cc (patch) | |
tree | 75699c1999c71a93dc8194a9cac338412e36d78d /drivers | |
parent | 80fac0f577a35c437219a2786c1804ab8ca1e998 (diff) | |
parent | b226acab2f6aaa45c2af27279b63f622b23a44bd (diff) | |
download | linux-0803e04011c2e107b9611660301edde94d7010cc.tar.xz |
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio/vhost updates from Michael Tsirkin:
- new vsock device support in host and guest
- platform IOMMU support in host and guest, including compatibility
quirks for legacy systems.
- misc fixes and cleanups.
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
VSOCK: Use kvfree()
vhost: split out vringh Kconfig
vhost: detect 32 bit integer wrap around
vhost: new device IOTLB API
vhost: drop vringh dependency
vhost: convert pre sorted vhost memory array to interval tree
vhost: introduce vhost memory accessors
VSOCK: Add Makefile and Kconfig
VSOCK: Introduce vhost_vsock.ko
VSOCK: Introduce virtio_transport.ko
VSOCK: Introduce virtio_vsock_common.ko
VSOCK: defer sock removal to transports
VSOCK: transport-specific vsock_transport functions
vhost: drop vringh dependency
vop: pull in vhost Kconfig
virtio: new feature to detect IOMMU device quirk
balloon: check the number of available pages in leak balloon
vhost: lockless enqueuing
vhost: simplify work flushing
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/Makefile | 1 | ||||
-rw-r--r-- | drivers/misc/mic/Kconfig | 4 | ||||
-rw-r--r-- | drivers/net/caif/Kconfig | 2 | ||||
-rw-r--r-- | drivers/vhost/Kconfig | 18 | ||||
-rw-r--r-- | drivers/vhost/Kconfig.vringh | 5 | ||||
-rw-r--r-- | drivers/vhost/Makefile | 4 | ||||
-rw-r--r-- | drivers/vhost/net.c | 67 | ||||
-rw-r--r-- | drivers/vhost/vhost.c | 927 | ||||
-rw-r--r-- | drivers/vhost/vhost.h | 64 | ||||
-rw-r--r-- | drivers/vhost/vsock.c | 719 | ||||
-rw-r--r-- | drivers/virtio/virtio_balloon.c | 2 | ||||
-rw-r--r-- | drivers/virtio/virtio_ring.c | 15 |
12 files changed, 1634 insertions, 194 deletions
diff --git a/drivers/Makefile b/drivers/Makefile index 9548244..53abb4a 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -138,6 +138,7 @@ obj-$(CONFIG_OF) += of/ obj-$(CONFIG_SSB) += ssb/ obj-$(CONFIG_BCMA) += bcma/ obj-$(CONFIG_VHOST_RING) += vhost/ +obj-$(CONFIG_VHOST) += vhost/ obj-$(CONFIG_VLYNQ) += vlynq/ obj-$(CONFIG_STAGING) += staging/ obj-y += platform/ diff --git a/drivers/misc/mic/Kconfig b/drivers/misc/mic/Kconfig index 89e5917..6fd9d36 100644 --- a/drivers/misc/mic/Kconfig +++ b/drivers/misc/mic/Kconfig @@ -146,3 +146,7 @@ config VOP More information about the Intel MIC family as well as the Linux OS and tools for MIC to use with this driver are available from <http://software.intel.com/en-us/mic-developer>. + +if VOP +source "drivers/vhost/Kconfig.vringh" +endif diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig index 5470980..f81df91 100644 --- a/drivers/net/caif/Kconfig +++ b/drivers/net/caif/Kconfig @@ -52,5 +52,5 @@ config CAIF_VIRTIO The caif driver for CAIF over Virtio. if CAIF_VIRTIO -source "drivers/vhost/Kconfig" +source "drivers/vhost/Kconfig.vringh" endif diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 533eaf0..40764ec 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -2,7 +2,6 @@ config VHOST_NET tristate "Host kernel accelerator for virtio net" depends on NET && EVENTFD && (TUN || !TUN) && (MACVTAP || !MACVTAP) select VHOST - select VHOST_RING ---help--- This kernel module can be loaded in host kernel to accelerate guest networking with virtio_net. Not to be confused with virtio_net @@ -15,17 +14,24 @@ config VHOST_SCSI tristate "VHOST_SCSI TCM fabric driver" depends on TARGET_CORE && EVENTFD && m select VHOST - select VHOST_RING default n ---help--- Say M here to enable the vhost_scsi TCM fabric module for use with virtio-scsi guests -config VHOST_RING - tristate +config VHOST_VSOCK + tristate "vhost virtio-vsock driver" + depends on VSOCKETS && EVENTFD + select VIRTIO_VSOCKETS_COMMON + select VHOST + default n ---help--- - This option is selected by any driver which needs to access - the host side of a virtio ring. + This kernel module can be loaded in the host kernel to provide AF_VSOCK + sockets for communicating with guests. The guests must have the + virtio_transport.ko driver loaded to use the virtio-vsock device. + + To compile this driver as a module, choose M here: the module will be called + vhost_vsock. config VHOST tristate diff --git a/drivers/vhost/Kconfig.vringh b/drivers/vhost/Kconfig.vringh new file mode 100644 index 0000000..6a4490c --- /dev/null +++ b/drivers/vhost/Kconfig.vringh @@ -0,0 +1,5 @@ +config VHOST_RING + tristate + ---help--- + This option is selected by any driver which needs to access + the host side of a virtio ring. diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile index e0441c3..6b012b9 100644 --- a/drivers/vhost/Makefile +++ b/drivers/vhost/Makefile @@ -4,5 +4,9 @@ vhost_net-y := net.o obj-$(CONFIG_VHOST_SCSI) += vhost_scsi.o vhost_scsi-y := scsi.o +obj-$(CONFIG_VHOST_VSOCK) += vhost_vsock.o +vhost_vsock-y := vsock.o + obj-$(CONFIG_VHOST_RING) += vringh.o + obj-$(CONFIG_VHOST) += vhost.o diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index e032ca3..5dc128a 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -61,7 +61,8 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" enum { VHOST_NET_FEATURES = VHOST_FEATURES | (1ULL << VHOST_NET_F_VIRTIO_NET_HDR) | - (1ULL << VIRTIO_NET_F_MRG_RXBUF) + (1ULL << VIRTIO_NET_F_MRG_RXBUF) | + (1ULL << VIRTIO_F_IOMMU_PLATFORM) }; enum { @@ -334,7 +335,7 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, { unsigned long uninitialized_var(endtime); int r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - out_num, in_num, NULL, NULL); + out_num, in_num, NULL, NULL); if (r == vq->num && vq->busyloop_timeout) { preempt_disable(); @@ -344,7 +345,7 @@ static int vhost_net_tx_get_vq_desc(struct vhost_net *net, cpu_relax_lowlatency(); preempt_enable(); r = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), - out_num, in_num, NULL, NULL); + out_num, in_num, NULL, NULL); } return r; @@ -377,6 +378,9 @@ static void handle_tx(struct vhost_net *net) if (!sock) goto out; + if (!vq_iotlb_prefetch(vq)) + goto out; + vhost_disable_notify(&net->dev, vq); hdr_size = nvq->vhost_hlen; @@ -652,6 +656,10 @@ static void handle_rx(struct vhost_net *net) sock = vq->private_data; if (!sock) goto out; + + if (!vq_iotlb_prefetch(vq)) + goto out; + vhost_disable_notify(&net->dev, vq); vhost_net_disable_vq(net, vq); @@ -1052,20 +1060,20 @@ static long vhost_net_reset_owner(struct vhost_net *n) struct socket *tx_sock = NULL; struct socket *rx_sock = NULL; long err; - struct vhost_memory *memory; + struct vhost_umem *umem; mutex_lock(&n->dev.mutex); err = vhost_dev_check_owner(&n->dev); if (err) goto done; - memory = vhost_dev_reset_owner_prepare(); - if (!memory) { + umem = vhost_dev_reset_owner_prepare(); + if (!umem) { err = -ENOMEM; goto done; } vhost_net_stop(n, &tx_sock, &rx_sock); vhost_net_flush(n); - vhost_dev_reset_owner(&n->dev, memory); + vhost_dev_reset_owner(&n->dev, umem); vhost_net_vq_reset(n); done: mutex_unlock(&n->dev.mutex); @@ -1096,10 +1104,14 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) } mutex_lock(&n->dev.mutex); if ((features & (1 << VHOST_F_LOG_ALL)) && - !vhost_log_access_ok(&n->dev)) { - mutex_unlock(&n->dev.mutex); - return -EFAULT; + !vhost_log_access_ok(&n->dev)) + goto out_unlock; + + if ((features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))) { + if (vhost_init_device_iotlb(&n->dev, true)) + goto out_unlock; } + for (i = 0; i < VHOST_NET_VQ_MAX; ++i) { mutex_lock(&n->vqs[i].vq.mutex); n->vqs[i].vq.acked_features = features; @@ -1109,6 +1121,10 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features) } mutex_unlock(&n->dev.mutex); return 0; + +out_unlock: + mutex_unlock(&n->dev.mutex); + return -EFAULT; } static long vhost_net_set_owner(struct vhost_net *n) @@ -1182,9 +1198,40 @@ static long vhost_net_compat_ioctl(struct file *f, unsigned int ioctl, } #endif +static ssize_t vhost_net_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + int noblock = file->f_flags & O_NONBLOCK; + + return vhost_chr_read_iter(dev, to, noblock); +} + +static ssize_t vhost_net_chr_write_iter(struct kiocb *iocb, + struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + + return vhost_chr_write_iter(dev, from); +} + +static unsigned int vhost_net_chr_poll(struct file *file, poll_table *wait) +{ + struct vhost_net *n = file->private_data; + struct vhost_dev *dev = &n->dev; + + return vhost_chr_poll(file, dev, wait); +} + static const struct file_operations vhost_net_fops = { .owner = THIS_MODULE, .release = vhost_net_release, + .read_iter = vhost_net_chr_read_iter, + .write_iter = vhost_net_chr_write_iter, + .poll = vhost_net_chr_poll, .unlocked_ioctl = vhost_net_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = vhost_net_compat_ioctl, diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 669fef1..c6f2d89 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -27,6 +27,7 @@ #include <linux/cgroup.h> #include <linux/module.h> #include <linux/sort.h> +#include <linux/interval_tree_generic.h> #include "vhost.h" @@ -34,6 +35,10 @@ static ushort max_mem_regions = 64; module_param(max_mem_regions, ushort, 0444); MODULE_PARM_DESC(max_mem_regions, "Maximum number of memory regions in memory map. (default: 64)"); +static int max_iotlb_entries = 2048; +module_param(max_iotlb_entries, int, 0444); +MODULE_PARM_DESC(max_iotlb_entries, + "Maximum number of iotlb entries. (default: 2048)"); enum { VHOST_MEMORY_F_LOG = 0x1, @@ -42,6 +47,10 @@ enum { #define vhost_used_event(vq) ((__virtio16 __user *)&vq->avail->ring[vq->num]) #define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num]) +INTERVAL_TREE_DEFINE(struct vhost_umem_node, + rb, __u64, __subtree_last, + START, LAST, , vhost_umem_interval_tree); + #ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY static void vhost_disable_cross_endian(struct vhost_virtqueue *vq) { @@ -131,6 +140,19 @@ static void vhost_reset_is_le(struct vhost_virtqueue *vq) vq->is_le = virtio_legacy_is_little_endian(); } +struct vhost_flush_struct { + struct vhost_work work; + struct completion wait_event; +}; + +static void vhost_flush_work(struct vhost_work *work) +{ + struct vhost_flush_struct *s; + + s = container_of(work, struct vhost_flush_struct, work); + complete(&s->wait_event); +} + static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) { @@ -155,11 +177,9 @@ static int vhost_poll_wakeup(wait_queue_t *wait, unsigned mode, int sync, void vhost_work_init(struct vhost_work *work, vhost_work_fn_t fn) { - INIT_LIST_HEAD(&work->node); + clear_bit(VHOST_WORK_QUEUED, &work->flags); work->fn = fn; init_waitqueue_head(&work->done); - work->flushing = 0; - work->queue_seq = work->done_seq = 0; } EXPORT_SYMBOL_GPL(vhost_work_init); @@ -211,31 +231,17 @@ void vhost_poll_stop(struct vhost_poll *poll) } EXPORT_SYMBOL_GPL(vhost_poll_stop); -static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work, - unsigned seq) -{ - int left; - - spin_lock_irq(&dev->work_lock); - left = seq - work->done_seq; - spin_unlock_irq(&dev->work_lock); - return left <= 0; -} - void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work) { - unsigned seq; - int flushing; + struct vhost_flush_struct flush; - spin_lock_irq(&dev->work_lock); - seq = work->queue_seq; - work->flushing++; - spin_unlock_irq(&dev->work_lock); - wait_event(work->done, vhost_work_seq_done(dev, work, seq)); - spin_lock_irq(&dev->work_lock); - flushing = --work->flushing; - spin_unlock_irq(&dev->work_lock); - BUG_ON(flushing < 0); + if (dev->worker) { + init_completion(&flush.wait_event); + vhost_work_init(&flush.work, vhost_flush_work); + + vhost_work_queue(dev, &flush.work); + wait_for_completion(&flush.wait_event); + } } EXPORT_SYMBOL_GPL(vhost_work_flush); @@ -249,16 +255,16 @@ EXPORT_SYMBOL_GPL(vhost_poll_flush); void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work) { - unsigned long flags; + if (!dev->worker) + return; - spin_lock_irqsave(&dev->work_lock, flags); - if (list_empty(&work->node)) { - list_add_tail(&work->node, &dev->work_list); - work->queue_seq++; - spin_unlock_irqrestore(&dev->work_lock, flags); + if (!test_and_set_bit(VHOST_WORK_QUEUED, &work->flags)) { + /* We can only add the work to the list after we're + * sure it was not in the list. + */ + smp_mb(); + llist_add(&work->node, &dev->work_list); wake_up_process(dev->worker); - } else { - spin_unlock_irqrestore(&dev->work_lock, flags); } } EXPORT_SYMBOL_GPL(vhost_work_queue); @@ -266,7 +272,7 @@ EXPORT_SYMBOL_GPL(vhost_work_queue); /* A lockless hint for busy polling code to exit the loop */ bool vhost_has_work(struct vhost_dev *dev) { - return !list_empty(&dev->work_list); + return !llist_empty(&dev->work_list); } EXPORT_SYMBOL_GPL(vhost_has_work); @@ -300,17 +306,18 @@ static void vhost_vq_reset(struct vhost_dev *dev, vq->call_ctx = NULL; vq->call = NULL; vq->log_ctx = NULL; - vq->memory = NULL; vhost_reset_is_le(vq); vhost_disable_cross_endian(vq); vq->busyloop_timeout = 0; + vq->umem = NULL; + vq->iotlb = NULL; } static int vhost_worker(void *data) { struct vhost_dev *dev = data; - struct vhost_work *work = NULL; - unsigned uninitialized_var(seq); + struct vhost_work *work, *work_next; + struct llist_node *node; mm_segment_t oldfs = get_fs(); set_fs(USER_DS); @@ -320,35 +327,25 @@ static int vhost_worker(void *data) /* mb paired w/ kthread_stop */ set_current_state(TASK_INTERRUPTIBLE); - spin_lock_irq(&dev->work_lock); - if (work) { - work->done_seq = seq; - if (work->flushing) - wake_up_all(&work->done); - } - if (kthread_should_stop()) { - spin_unlock_irq(&dev->work_lock); __set_current_state(TASK_RUNNING); break; } - if (!list_empty(&dev->work_list)) { - work = list_first_entry(&dev->work_list, - struct vhost_work, node); - list_del_init(&work->node); - seq = work->queue_seq; - } else - work = NULL; - spin_unlock_irq(&dev->work_lock); - if (work) { + node = llist_del_all(&dev->work_list); + if (!node) + schedule(); + + node = llist_reverse_order(node); + /* make sure flag is seen after deletion */ + smp_wmb(); + llist_for_each_entry_safe(work, work_next, node, node) { + clear_bit(VHOST_WORK_QUEUED, &work->flags); __set_current_state(TASK_RUNNING); work->fn(work); if (need_resched()) schedule(); - } else - schedule(); - + } } unuse_mm(dev->mm); set_fs(oldfs); @@ -407,11 +404,16 @@ void vhost_dev_init(struct vhost_dev *dev, mutex_init(&dev->mutex); dev->log_ctx = NULL; dev->log_file = NULL; - dev->memory = NULL; + dev->umem = NULL; + dev->iotlb = NULL; dev->mm = NULL; - spin_lock_init(&dev->work_lock); - INIT_LIST_HEAD(&dev->work_list); dev->worker = NULL; + init_llist_head(&dev->work_list); + init_waitqueue_head(&dev->wait); + INIT_LIST_HEAD(&dev->read_list); + INIT_LIST_HEAD(&dev->pending_list); + spin_lock_init(&dev->iotlb_lock); + for (i = 0; i < dev->nvqs; ++i) { vq = dev->vqs[i]; @@ -512,27 +514,36 @@ err_mm: } EXPORT_SYMBOL_GPL(vhost_dev_set_owner); -struct vhost_memory *vhost_dev_reset_owner_prepare(void) +static void *vhost_kvzalloc(unsigned long size) { - return kmalloc(offsetof(struct vhost_memory, regions), GFP_KERNEL); + void *n = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + + if (!n) + n = vzalloc(size); + return n; +} + +struct vhost_umem *vhost_dev_reset_owner_prepare(void) +{ + return vhost_kvzalloc(sizeof(struct vhost_umem)); } EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare); /* Caller should have device mutex */ -void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_memory *memory) +void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_umem *umem) { int i; vhost_dev_cleanup(dev, true); /* Restore memory to default empty mapping. */ - memory->nregions = 0; - dev->memory = memory; + INIT_LIST_HEAD(&umem->umem_list); + dev->umem = umem; /* We don't need VQ locks below since vhost_dev_cleanup makes sure * VQs aren't running. */ for (i = 0; i < dev->nvqs; ++i) - dev->vqs[i]->memory = memory; + dev->vqs[i]->umem = umem; } EXPORT_SYMBOL_GPL(vhost_dev_reset_owner); @@ -549,6 +560,47 @@ void vhost_dev_stop(struct vhost_dev *dev) } EXPORT_SYMBOL_GPL(vhost_dev_stop); +static void vhost_umem_free(struct vhost_umem *umem, + struct vhost_umem_node *node) +{ + vhost_umem_interval_tree_remove(node, &umem->umem_tree); + list_del(&node->link); + kfree(node); + umem->numem--; +} + +static void vhost_umem_clean(struct vhost_umem *umem) +{ + struct vhost_umem_node *node, *tmp; + + if (!umem) + return; + + list_for_each_entry_safe(node, tmp, &umem->umem_list, link) + vhost_umem_free(umem, node); + + kvfree(umem); +} + +static void vhost_clear_msg(struct vhost_dev *dev) +{ + struct vhost_msg_node *node, *n; + + spin_lock(&dev->iotlb_lock); + + list_for_each_entry_safe(node, n, &dev->read_list, node) { + list_del(&node->node); + kfree(node); + } + + list_for_each_entry_safe(node, n, &dev->pending_list, node) { + list_del(&node->node); + kfree(node); + } + + spin_unlock(&dev->iotlb_lock); +} + /* Caller should have device mutex if and only if locked is set */ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) { @@ -575,9 +627,13 @@ void vhost_dev_cleanup(struct vhost_dev *dev, bool locked) fput(dev->log_file); dev->log_file = NULL; /* No one will access memory at this point */ - kvfree(dev->memory); - dev->memory = NULL; - WARN_ON(!list_empty(&dev->work_list)); + vhost_umem_clean(dev->umem); + dev->umem = NULL; + vhost_umem_clean(dev->iotlb); + dev->iotlb = NULL; + vhost_clear_msg(dev); + wake_up_interruptible_poll(&dev->wait, POLLIN | POLLRDNORM); + WARN_ON(!llist_empty(&dev->work_list)); if (dev->worker) { kthread_stop(dev->worker); dev->worker = NULL; @@ -601,26 +657,34 @@ static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) (sz + VHOST_PAGE_SIZE * 8 - 1) / VHOST_PAGE_SIZE / 8); } +static bool vhost_overflow(u64 uaddr, u64 size) +{ + /* Make sure 64 bit math will not overflow. */ + return uaddr > ULONG_MAX || size > ULONG_MAX || uaddr > ULONG_MAX - size; +} + /* Caller should have vq mutex and device mutex. */ -static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem, +static int vq_memory_access_ok(void __user *log_base, struct vhost_umem *umem, int log_all) { - int i; + struct vhost_umem_node *node; - if (!mem) + if (!umem) return 0; - for (i = 0; i < mem->nregions; ++i) { - struct vhost_memory_region *m = mem->regions + i; - unsigned long a = m->userspace_addr; - if (m->memory_size > ULONG_MAX) + list_for_each_entry(node, &umem->umem_list, link) { + unsigned long a = node->userspace_addr; + + if (vhost_overflow(node->userspace_addr, node->size)) return 0; - else if (!access_ok(VERIFY_WRITE, (void __user *)a, - m->memory_size)) + + + if (!access_ok(VERIFY_WRITE, (void __user *)a, + node->size)) return 0; else if (log_all && !log_access_ok(log_base, - m->guest_phys_addr, - m->memory_size)) + node->start, + node->size)) return 0; } return 1; @@ -628,7 +692,7 @@ static int vq_memory_access_ok(void __user *log_base, struct vhost_memory *mem, /* Can we switch to this memory table? */ /* Caller should have device mutex but not vq mutex */ -static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, +static int memory_access_ok(struct vhost_dev *d, struct vhost_umem *umem, int log_all) { int i; @@ -641,7 +705,8 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, log = log_all || vhost_has_feature(d->vqs[i], VHOST_F_LOG_ALL); /* If ring is inactive, will check when it's enabled. */ if (d->vqs[i]->private_data) - ok = vq_memory_access_ok(d->vqs[i]->log_base, mem, log); + ok = vq_memory_access_ok(d->vqs[i]->log_base, + umem, log); else ok = 1; mutex_unlock(&d->vqs[i]->mutex); @@ -651,12 +716,385 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, return 1; } +static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, + struct iovec iov[], int iov_size, int access); + +static int vhost_copy_to_user(struct vhost_virtqueue *vq, void *to, + const void *from, unsigned size) +{ + int ret; + + if (!vq->iotlb) + return __copy_to_user(to, from, size); + else { + /* This function should be called after iotlb + * prefetch, which means we're sure that all vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + struct iov_iter t; + ret = translate_desc(vq, (u64)(uintptr_t)to, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_WO); + if (ret < 0) + goto out; + iov_iter_init(&t, WRITE, vq->iotlb_iov, ret, size); + ret = copy_to_iter(from, size, &t); + if (ret == size) + ret = 0; + } +out: + return ret; +} + +static int vhost_copy_from_user(struct vhost_virtqueue *vq, void *to, + void *from, unsigned size) +{ + int ret; + + if (!vq->iotlb) + return __copy_from_user(to, from, size); + else { + /* This function should be called after iotlb + * prefetch, which means we're sure that vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + struct iov_iter f; + ret = translate_desc(vq, (u64)(uintptr_t)from, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_RO); + if (ret < 0) { + vq_err(vq, "IOTLB translation failure: uaddr " + "%p size 0x%llx\n", from, + (unsigned long long) size); + goto out; + } + iov_iter_init(&f, READ, vq->iotlb_iov, ret, size); + ret = copy_from_iter(to, size, &f); + if (ret == size) + ret = 0; + } + +out: + return ret; +} + +static void __user *__vhost_get_user(struct vhost_virtqueue *vq, + void *addr, unsigned size) +{ + int ret; + + /* This function should be called after iotlb + * prefetch, which means we're sure that vq + * could be access through iotlb. So -EAGAIN should + * not happen in this case. + */ + /* TODO: more fast path */ + ret = translate_desc(vq, (u64)(uintptr_t)addr, size, vq->iotlb_iov, + ARRAY_SIZE(vq->iotlb_iov), + VHOST_ACCESS_RO); + if (ret < 0) { + vq_err(vq, "IOTLB translation failure: uaddr " + "%p size 0x%llx\n", addr, + (unsigned long long) size); + return NULL; + } + + if (ret != 1 || vq->iotlb_iov[0].iov_len != size) { + vq_err(vq, "Non atomic userspace memory access: uaddr " + "%p size 0x%llx\n", addr, + (unsigned long long) size); + return NULL; + } + + return vq->iotlb_iov[0].iov_base; +} + +#define vhost_put_user(vq, x, ptr) \ +({ \ + int ret = -EFAULT; \ + if (!vq->iotlb) { \ + ret = __put_user(x, ptr); \ + } else { \ + __typeof__(ptr) to = \ + (__typeof__(ptr)) __vhost_get_user(vq, ptr, sizeof(*ptr)); \ + if (to != NULL) \ + ret = __put_user(x, to); \ + else \ + ret = -EFAULT; \ + } \ + ret; \ +}) + +#define vhost_get_user(vq, x, ptr) \ +({ \ + int ret; \ + if (!vq->iotlb) { \ + ret = __get_user(x, ptr); \ + } else { \ + __typeof__(ptr) from = \ + (__typeof__(ptr)) __vhost_get_user(vq, ptr, sizeof(*ptr)); \ + if (from != NULL) \ + ret = __get_user(x, from); \ + else \ + ret = -EFAULT; \ + } \ + ret; \ +}) + +static void vhost_dev_lock_vqs(struct vhost_dev *d) +{ + int i = 0; + for (i = 0; i < d->nvqs; ++i) + mutex_lock(&d->vqs[i]->mutex); +} + +static void vhost_dev_unlock_vqs(struct vhost_dev *d) +{ + int i = 0; + for (i = 0; i < d->nvqs; ++i) + mutex_unlock(&d->vqs[i]->mutex); +} + +static int vhost_new_umem_range(struct vhost_umem *umem, + u64 start, u64 size, u64 end, + u64 userspace_addr, int perm) +{ + struct vhost_umem_node *tmp, *node = kmalloc(sizeof(*node), GFP_ATOMIC); + + if (!node) + return -ENOMEM; + + if (umem->numem == max_iotlb_entries) { + tmp = list_first_entry(&umem->umem_list, typeof(*tmp), link); + vhost_umem_free(umem, tmp); + } + + node->start = start; + node->size = size; + node->last = end; + node->userspace_addr = userspace_addr; + node->perm = perm; + INIT_LIST_HEAD(&node->link); + list_add_tail(&node->link, &umem->umem_list); + vhost_umem_interval_tree_insert(node, &umem->umem_tree); + umem->numem++; + + return 0; +} + +static void vhost_del_umem_range(struct vhost_umem *umem, + u64 start, u64 end) +{ + struct vhost_umem_node *node; + + while ((node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + start, end))) + vhost_umem_free(umem, node); +} + +static void vhost_iotlb_notify_vq(struct vhost_dev *d, + struct vhost_iotlb_msg *msg) +{ + struct vhost_msg_node *node, *n; + + spin_lock(&d->iotlb_lock); + + list_for_each_entry_safe(node, n, &d->pending_list, node) { + struct vhost_iotlb_msg *vq_msg = &node->msg.iotlb; + if (msg->iova <= vq_msg->iova && + msg->iova + msg->size - 1 > vq_msg->iova && + vq_msg->type == VHOST_IOTLB_MISS) { + vhost_poll_queue(&node->vq->poll); + list_del(&node->node); + kfree(node); + } + } + + spin_unlock(&d->iotlb_lock); +} + +static int umem_access_ok(u64 uaddr, u64 size, int access) +{ + unsigned long a = uaddr; + + /* Make sure 64 bit math will not overflow. */ + if (vhost_overflow(uaddr, size)) + return -EFAULT; + + if ((access & VHOST_ACCESS_RO) && + !access_ok(VERIFY_READ, (void __user *)a, size)) + return -EFAULT; + if ((access & VHOST_ACCESS_WO) && + !access_ok(VERIFY_WRITE, (void __user *)a, size)) + return -EFAULT; + return 0; +} + +int vhost_process_iotlb_msg(struct vhost_dev *dev, + struct vhost_iotlb_msg *msg) +{ + int ret = 0; + + vhost_dev_lock_vqs(dev); + switch (msg->type) { + case VHOST_IOTLB_UPDATE: + if (!dev->iotlb) { + ret = -EFAULT; + break; + } + if (umem_access_ok(msg->uaddr, msg->size, msg->perm)) { + ret = -EFAULT; + break; + } + if (vhost_new_umem_range(dev->iotlb, msg->iova, msg->size, + msg->iova + msg->size - 1, + msg->uaddr, msg->perm)) { + ret = -ENOMEM; + break; + } + vhost_iotlb_notify_vq(dev, msg); + break; + case VHOST_IOTLB_INVALIDATE: + vhost_del_umem_range(dev->iotlb, msg->iova, + msg->iova + msg->size - 1); + break; + default: + ret = -EINVAL; + break; + } + + vhost_dev_unlock_vqs(dev); + return ret; +} +ssize_t vhost_chr_write_iter(struct vhost_dev *dev, + struct iov_iter *from) +{ + struct vhost_msg_node node; + unsigned size = sizeof(struct vhost_msg); + size_t ret; + int err; + + if (iov_iter_count(from) < size) + return 0; + ret = copy_from_iter(&node.msg, size, from); + if (ret != size) + goto done; + + switch (node.msg.type) { + case VHOST_IOTLB_MSG: + err = vhost_process_iotlb_msg(dev, &node.msg.iotlb); + if (err) + ret = err; + break; + default: + ret = -EINVAL; + break; + } + +done: + return ret; +} +EXPORT_SYMBOL(vhost_chr_write_iter); + +unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev, + poll_table *wait) +{ + unsigned int mask = 0; + + poll_wait(file, &dev->wait, wait); + + if (!list_empty(&dev->read_list)) + mask |= POLLIN | POLLRDNORM; + + return mask; +} +EXPORT_SYMBOL(vhost_chr_poll); + +ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to, + int noblock) +{ + DEFINE_WAIT(wait); + struct vhost_msg_node *node; + ssize_t ret = 0; + unsigned size = sizeof(struct vhost_msg); + + if (iov_iter_count(to) < size) + return 0; + + while (1) { + if (!noblock) + prepare_to_wait(&dev->wait, &wait, + TASK_INTERRUPTIBLE); + + node = vhost_dequeue_msg(dev, &dev->read_list); + if (node) + break; + if (noblock) { + ret = -EAGAIN; + break; + } + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + if (!dev->iotlb) { + ret = -EBADFD; + break; + } + + schedule(); + } + + if (!noblock) + finish_wait(&dev->wait, &wait); + + if (node) { + ret = copy_to_iter(&node->msg, size, to); + + if (ret != size || node->msg.type != VHOST_IOTLB_MISS) { + kfree(node); + return ret; + } + + vhost_enqueue_msg(dev, &dev->pending_list, node); + } + + return ret; +} +EXPORT_SYMBOL_GPL(vhost_chr_read_iter); + +static int vhost_iotlb_miss(struct vhost_virtqueue *vq, u64 iova, int access) +{ + struct vhost_dev *dev = vq->dev; + struct vhost_msg_node *node; + struct vhost_iotlb_msg *msg; + + node = vhost_new_msg(vq, VHOST_IOTLB_MISS); + if (!node) + return -ENOMEM; + + msg = &node->msg.iotlb; + msg->type = VHOST_IOTLB_MISS; + msg->iova = iova; + msg->perm = access; + + vhost_enqueue_msg(dev, &dev->read_list, node); + + return 0; +} + static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, struct vring_desc __user *desc, struct vring_avail __user *avail, struct vring_used __user *used) + { size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + return access_ok(VERIFY_READ, desc, num * sizeof *desc) && access_ok(VERIFY_READ, avail, sizeof *avail + num * sizeof *avail->ring + s) && @@ -664,11 +1102,59 @@ static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num, sizeof *used + num * sizeof *used->ring + s); } +static int iotlb_access_ok(struct vhost_virtqueue *vq, + int access, u64 addr, u64 len) +{ + const struct vhost_umem_node *node; + struct vhost_umem *umem = vq->iotlb; + u64 s = 0, size; + + while (len > s) { + node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + addr, + addr + len - 1); + if (node == NULL || node->start > addr) { + vhost_iotlb_miss(vq, addr, access); + return false; + } else if (!(node->perm & access)) { + /* Report the possible access violation by + * request another translation from userspace. + */ + return false; + } + + size = node->size - addr + node->start; + s += size; + addr += size; + } + + return true; +} + +int vq_iotlb_prefetch(struct vhost_virtqueue *vq) +{ + size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; + unsigned int num = vq->num; + + if (!vq->iotlb) + return 1; + + return iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->desc, + num * sizeof *vq->desc) && + iotlb_access_ok(vq, VHOST_ACCESS_RO, (u64)(uintptr_t)vq->avail, + sizeof *vq->avail + + num * sizeof *vq->avail->ring + s) && + iotlb_access_ok(vq, VHOST_ACCESS_WO, (u64)(uintptr_t)vq->used, + sizeof *vq->used + + num * sizeof *vq->used->ring + s); +} +EXPORT_SYMBOL_GPL(vq_iotlb_prefetch); + /* Can we log writes? */ /* Caller should have device mutex but not vq mutex */ int vhost_log_access_ok(struct vhost_dev *dev) { - return memory_access_ok(dev, dev->memory, 1); + return memory_access_ok(dev, dev->umem, 1); } EXPORT_SYMBOL_GPL(vhost_log_access_ok); @@ -679,7 +1165,7 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, { size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0; - return vq_memory_access_ok(log_base, vq->memory, + return vq_memory_access_ok(log_base, vq->umem, vhost_has_feature(vq, VHOST_F_LOG_ALL)) && (!vq->log_used || log_access_ok(log_base, vq->log_addr, sizeof *vq->used + @@ -690,33 +1176,36 @@ static int vq_log_access_ok(struct vhost_virtqueue *vq, /* Caller should have vq mutex and device mutex */ int vhost_vq_access_ok(struct vhost_virtqueue *vq) { + if (vq->iotlb) { + /* When device IOTLB was used, the access validation + * will be validated during prefetching. + */ + return 1; + } return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used) && vq_log_access_ok(vq, vq->log_base); } EXPORT_SYMBOL_GPL(vhost_vq_access_ok); -static int vhost_memory_reg_sort_cmp(const void *p1, const void *p2) +static struct vhost_umem *vhost_umem_alloc(void) { - const struct vhost_memory_region *r1 = p1, *r2 = p2; - if (r1->guest_phys_addr < r2->guest_phys_addr) - return 1; - if (r1->guest_phys_addr > r2->guest_phys_addr) - return -1; - return 0; -} + struct vhost_umem *umem = vhost_kvzalloc(sizeof(*umem)); -static void *vhost_kvzalloc(unsigned long size) -{ - void *n = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!umem) + return NULL; - if (!n) - n = vzalloc(size); - return n; + umem->umem_tree = RB_ROOT; + umem->numem = 0; + INIT_LIST_HEAD(&umem->umem_list); + + return umem; } static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) { - struct vhost_memory mem, *newmem, *oldmem; + struct vhost_memory mem, *newmem; + struct vhost_memory_region *region; + struct vhost_umem *newumem, *oldumem; unsigned long size = offsetof(struct vhost_memory, regions); int i; @@ -736,24 +1225,47 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) kvfree(newmem); return -EFAULT; } - sort(newmem->regions, newmem->nregions, sizeof(*newmem->regions), - vhost_memory_reg_sort_cmp, NULL); - if (!memory_access_ok(d, newmem, 0)) { + newumem = vhost_umem_alloc(); + if (!newumem) { kvfree(newmem); - return -EFAULT; + return -ENOMEM; } - oldmem = d->memory; - d->memory = newmem; + + for (region = newmem->regions; + region < newmem->regions + mem.nregions; + region++) { + if (vhost_new_umem_range(newumem, + region->guest_phys_addr, + region->memory_size, + region->guest_phys_addr + + region->memory_size - 1, + region->userspace_addr, + VHOST_ACCESS_RW)) + goto err; + } + + if (!memory_access_ok(d, newumem, 0)) + goto err; + + oldumem = d->umem; + d->umem = newumem; /* All memory accesses are done under some VQ mutex. */ for (i = 0; i < d->nvqs; ++i) { mutex_lock(&d->vqs[i]->mutex); - d->vqs[i]->memory = newmem; + d->vqs[i]->umem = newumem; mutex_unlock(&d->vqs[i]->mutex); } - kvfree(oldmem); + + kvfree(newmem); + vhost_umem_clean(oldumem); return 0; + +err: + vhost_umem_clean(newumem); + kvfree(newmem); + return -EFAULT; } long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) @@ -974,6 +1486,30 @@ long vhost_vring_ioctl(struct vhost_dev *d, int ioctl, void __user *argp) } EXPORT_SYMBOL_GPL(vhost_vring_ioctl); +int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled) +{ + struct vhost_umem *niotlb, *oiotlb; + int i; + + niotlb = vhost_umem_alloc(); + if (!niotlb) + return -ENOMEM; + + oiotlb = d->iotlb; + d->iotlb = niotlb; + + for (i = 0; i < d->nvqs; ++i) { + mutex_lock(&d->vqs[i]->mutex); + d->vqs[i]->iotlb = niotlb; + mutex_unlock(&d->vqs[i]->mutex); + } + + vhost_umem_clean(oiotlb); + + return 0; +} +EXPORT_SYMBOL_GPL(vhost_init_device_iotlb); + /* Caller must have device mutex */ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { @@ -1056,28 +1592,6 @@ done: } EXPORT_SYMBOL_GPL(vhost_dev_ioctl); -static const struct vhost_memory_region *find_region(struct vhost_memory *mem, - __u64 addr, __u32 len) -{ - const struct vhost_memory_region *reg; - int start = 0, end = mem->nregions; - - while (start < end) { - int slot = start + (end - start) / 2; - reg = mem->regions + slot; - if (addr >= reg->guest_phys_addr) - end = slot; - else - start = slot + 1; - } - - reg = mem->regions + start; - if (addr >= reg->guest_phys_addr && - reg->guest_phys_addr + reg->memory_size > addr) - return reg; - return NULL; -} - /* TODO: This is really inefficient. We need something like get_user() * (instruction directly accesses the data, with an exception table entry * returning -EFAULT). See Documentation/x86/exception-tables.txt. @@ -1156,7 +1670,8 @@ EXPORT_SYMBOL_GPL(vhost_log_write); static int vhost_update_used_flags(struct vhost_virtqueue *vq) { void __user *used; - if (__put_user(cpu_to_vhost16(vq, vq->used_flags), &vq->used->flags) < 0) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->used_flags), + &vq->used->flags) < 0) return -EFAULT; if (unlikely(vq->log_used)) { /* Make sure the flag is seen before log. */ @@ -1174,7 +1689,8 @@ static int vhost_update_used_flags(struct vhost_virtqueue *vq) static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event) { - if (__put_user(cpu_to_vhost16(vq, vq->avail_idx), vhost_avail_event(vq))) + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->avail_idx), + vhost_avail_event(vq))) return -EFAULT; if (unlikely(vq->log_used)) { void __user *used; @@ -1208,15 +1724,20 @@ int vhost_vq_init_access(struct vhost_virtqueue *vq) if (r) goto err; vq->signalled_used_valid = false; - if (!access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) { + if (!vq->iotlb && + !access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx)) { r = -EFAULT; goto err; } - r = __get_user(last_used_idx, &vq->used->idx); - if (r) + r = vhost_get_user(vq, last_used_idx, &vq->used->idx); + if (r) { + vq_err(vq, "Can't access used idx at %p\n", + &vq->used->idx); goto err; + } vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx); return 0; + err: vq->is_le = is_le; return r; @@ -1224,36 +1745,48 @@ err: EXPORT_SYMBOL_GPL(vhost_vq_init_access); static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len, - struct iovec iov[], int iov_size) + struct iovec iov[], int iov_size, int access) { - const struct vhost_memory_region *reg; - struct vhost_memory *mem; + const struct vhost_umem_node *node; + struct vhost_dev *dev = vq->dev; + struct vhost_umem *umem = dev->iotlb ? dev->iotlb : dev->umem; struct iovec *_iov; u64 s = 0; int ret = 0; - mem = vq->memory; while ((u64)len > s) { u64 size; if (unlikely(ret >= iov_size)) { ret = -ENOBUFS; break; } - reg = find_region(mem, addr, len); - if (unlikely(!reg)) { - ret = -EFAULT; + + node = vhost_umem_interval_tree_iter_first(&umem->umem_tree, + addr, addr + len - 1); + if (node == NULL || node->start > addr) { + if (umem != dev->iotlb) { + ret = -EFAULT; + break; + } + ret = -EAGAIN; + break; + } else if (!(node->perm & access)) { + ret = -EPERM; break; } + _iov = iov + ret; - size = reg->memory_size - addr + reg->guest_phys_addr; + size = node->size - addr + node->start; _iov->iov_len = min((u64)len - s, size); _iov->iov_base = (void __user *)(unsigned long) - (reg->userspace_addr + addr - reg->guest_phys_addr); + (node->userspace_addr + addr - node->start); s += size; addr += size; ++ret; } + if (ret == -EAGAIN) + vhost_iotlb_miss(vq, addr, access); return ret; } @@ -1288,7 +1821,7 @@ static int get_indirect(struct vhost_virtqueue *vq, unsigned int i = 0, count, found = 0; u32 len = vhost32_to_cpu(vq, indirect->len); struct iov_iter from; - int ret; + int ret, access; /* Sanity check */ if (unlikely(len % sizeof desc)) { @@ -1300,9 +1833,10 @@ static int get_indirect(struct vhost_virtqueue *vq, } ret = translate_desc(vq, vhost64_to_cpu(vq, indirect->addr), len, vq->indirect, - UIO_MAXIOV); + UIO_MAXIOV, VHOST_ACCESS_RO); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d in indirect.\n", ret); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d in indirect.\n", ret); return ret; } iov_iter_init(&from, READ, vq->indirect, ret, len); @@ -1340,16 +1874,22 @@ static int get_indirect(struct vhost_virtqueue *vq, return -EINVAL; } + if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; + ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count); + iov_size - iov_count, access); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d indirect idx %d\n", - ret, i); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d indirect idx %d\n", + ret, i); return ret; } /* If this is an input descriptor, increment that count. */ - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) { + if (access == VHOST_ACCESS_WO) { *in_num += ret; if (unlikely(log)) { log[*log_num].addr = vhost64_to_cpu(vq, desc.addr); @@ -1388,11 +1928,11 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, u16 last_avail_idx; __virtio16 avail_idx; __virtio16 ring_head; - int ret; + int ret, access; /* Check it isn't doing very strange things with descriptor numbers. */ last_avail_idx = vq->last_avail_idx; - if (unlikely(__get_user(avail_idx, &vq->avail->idx))) { + if (unlikely(vhost_get_user(vq, avail_idx, &vq->avail->idx))) { vq_err(vq, "Failed to access avail idx at %p\n", &vq->avail->idx); return -EFAULT; @@ -1414,8 +1954,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, /* Grab the next descriptor number they're advertising, and increment * the index we've seen. */ - if (unlikely(__get_user(ring_head, - &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { + if (unlikely(vhost_get_user(vq, ring_head, + &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) { vq_err(vq, "Failed to read head: idx %d address %p\n", last_avail_idx, &vq->avail->ring[last_avail_idx % vq->num]); @@ -1450,7 +1990,8 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = vhost_copy_from_user(vq, &desc, vq->desc + i, + sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); @@ -1461,22 +2002,28 @@ int vhost_get_vq_desc(struct vhost_virtqueue *vq, out_num, in_num, log, log_num, &desc); if (unlikely(ret < 0)) { - vq_err(vq, "Failure detected " - "in indirect descriptor at idx %d\n", i); + if (ret != -EAGAIN) + vq_err(vq, "Failure detected " + "in indirect descriptor at idx %d\n", i); return ret; } continue; } + if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) + access = VHOST_ACCESS_WO; + else + access = VHOST_ACCESS_RO; ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr), vhost32_to_cpu(vq, desc.len), iov + iov_count, - iov_size - iov_count); + iov_size - iov_count, access); if (unlikely(ret < 0)) { - vq_err(vq, "Translation failure %d descriptor idx %d\n", - ret, i); + if (ret != -EAGAIN) + vq_err(vq, "Translation failure %d descriptor idx %d\n", + ret, i); return ret; } - if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) { + if (access == VHOST_ACCESS_WO) { /* If this is an input descriptor, * increment that count. */ *in_num += ret; @@ -1538,15 +2085,15 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq, start = vq->last_used_idx & (vq->num - 1); used = vq->used->ring + start; if (count == 1) { - if (__put_user(heads[0].id, &used->id)) { + if (vhost_put_user(vq, heads[0].id, &used->id)) { vq_err(vq, "Failed to write used id"); return -EFAULT; } - if (__put_user(heads[0].len, &used->len)) { + if (vhost_put_user(vq, heads[0].len, &used->len)) { vq_err(vq, "Failed to write used len"); return -EFAULT; } - } else if (__copy_to_user(used, heads, count * sizeof *used)) { + } else if (vhost_copy_to_user(vq, used, heads, count * sizeof *used)) { vq_err(vq, "Failed to write used"); return -EFAULT; } @@ -1590,7 +2137,8 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, /* Make sure buffer is written before we update index. */ smp_wmb(); - if (__put_user(cpu_to_vhost16(vq, vq->last_used_idx), &vq->used->idx)) { + if (vhost_put_user(vq, cpu_to_vhost16(vq, vq->last_used_idx), + &vq->used->idx)) { vq_err(vq, "Failed to increment used idx"); return -EFAULT; } @@ -1622,7 +2170,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) { __virtio16 flags; - if (__get_user(flags, &vq->avail->flags)) { + if (vhost_get_user(vq, flags, &vq->avail->flags)) { vq_err(vq, "Failed to get flags"); return true; } @@ -1636,7 +2184,7 @@ static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) if (unlikely(!v)) return true; - if (__get_user(event, vhost_used_event(vq))) { + if (vhost_get_user(vq, event, vhost_used_event(vq))) { vq_err(vq, "Failed to get used event idx"); return true; } @@ -1678,7 +2226,7 @@ bool vhost_vq_avail_empty(struct vhost_dev *dev, struct vhost_virtqueue *vq) __virtio16 avail_idx; int r; - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) return false; @@ -1713,7 +2261,7 @@ bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) /* They could have slipped one in as we were doing that: make * sure it's written, then check again. */ smp_mb(); - r = __get_user(avail_idx, &vq->avail->idx); + r = vhost_get_user(vq, avail_idx, &vq->avail->idx); if (r) { vq_err(vq, "Failed to check avail idx at %p: %d\n", &vq->avail->idx, r); @@ -1741,6 +2289,47 @@ void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq) } EXPORT_SYMBOL_GPL(vhost_disable_notify); +/* Create a new message. */ +struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type) +{ + struct vhost_msg_node *node = kmalloc(sizeof *node, GFP_KERNEL); + if (!node) + return NULL; + node->vq = vq; + node->msg.type = type; + return node; +} +EXPORT_SYMBOL_GPL(vhost_new_msg); + +void vhost_enqueue_msg(struct vhost_dev *dev, struct list_head *head, + struct vhost_msg_node *node) +{ + spin_lock(&dev->iotlb_lock); + list_add_tail(&node->node, head); + spin_unlock(&dev->iotlb_lock); + + wake_up_interruptible_poll(&dev->wait, POLLIN | POLLRDNORM); +} +EXPORT_SYMBOL_GPL(vhost_enqueue_msg); + +struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, + struct list_head *head) +{ + struct vhost_msg_node *node = NULL; + + spin_lock(&dev->iotlb_lock); + if (!list_empty(head)) { + node = list_first_entry(head, struct vhost_msg_node, + node); + list_del(&node->node); + } + spin_unlock(&dev->iotlb_lock); + + return node; +} +EXPORT_SYMBOL_GPL(vhost_dequeue_msg); + + static int __init vhost_init(void) { return 0; diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index d36d8be..78f3c5f 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h @@ -15,13 +15,15 @@ struct vhost_work; typedef void (*vhost_work_fn_t)(struct vhost_work *work); +#define VHOST_WORK_QUEUED 1 struct vhost_work { - struct list_head node; + struct llist_node node; vhost_work_fn_t fn; wait_queue_head_t done; int flushing; unsigned queue_seq; unsigned done_seq; + unsigned long flags; }; /* Poll a file (eventfd or socket) */ @@ -53,6 +55,27 @@ struct vhost_log { u64 len; }; +#define START(node) ((node)->start) +#define LAST(node) ((node)->last) + +struct vhost_umem_node { + struct rb_node rb; + struct list_head link; + __u64 start; + __u64 last; + __u64 size; + __u64 userspace_addr; + __u32 perm; + __u32 flags_padding; + __u64 __subtree_last; +}; + +struct vhost_umem { + struct rb_root umem_tree; + struct list_head umem_list; + int numem; +}; + /* The virtqueue structure describes a queue attached to a device. */ struct vhost_virtqueue { struct vhost_dev *dev; @@ -98,10 +121,12 @@ struct vhost_virtqueue { u64 log_addr; struct iovec iov[UIO_MAXIOV]; + struct iovec iotlb_iov[64]; struct iovec *indirect; struct vring_used_elem *heads; /* Protected by virtqueue mutex. */ - struct vhost_memory *memory; + struct vhost_umem *umem; + struct vhost_umem *iotlb; void *private_data; u64 acked_features; /* Log write descriptors */ @@ -118,25 +143,35 @@ struct vhost_virtqueue { u32 busyloop_timeout; }; +struct vhost_msg_node { + struct vhost_msg msg; + struct vhost_virtqueue *vq; + struct list_head node; +}; + struct vhost_dev { - struct vhost_memory *memory; struct mm_struct *mm; struct mutex mutex; struct vhost_virtqueue **vqs; int nvqs; struct file *log_file; struct eventfd_ctx *log_ctx; - spinlock_t work_lock; - struct list_head work_list; + struct llist_head work_list; struct task_struct *worker; + struct vhost_umem *umem; + struct vhost_umem *iotlb; + spinlock_t iotlb_lock; + struct list_head read_list; + struct list_head pending_list; + wait_queue_head_t wait; }; void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs); long vhost_dev_set_owner(struct vhost_dev *dev); bool vhost_dev_has_owner(struct vhost_dev *dev); long vhost_dev_check_owner(struct vhost_dev *); -struct vhost_memory *vhost_dev_reset_owner_prepare(void); -void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *); +struct vhost_umem *vhost_dev_reset_owner_prepare(void); +void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_umem *); void vhost_dev_cleanup(struct vhost_dev *, bool locked); void vhost_dev_stop(struct vhost_dev *); long vhost_dev_ioctl(struct vhost_dev *, unsigned int ioctl, void __user *argp); @@ -165,6 +200,21 @@ bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *); int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log, unsigned int log_num, u64 len); +int vq_iotlb_prefetch(struct vhost_virtqueue *vq); + +struct vhost_msg_node *vhost_new_msg(struct vhost_virtqueue *vq, int type); +void vhost_enqueue_msg(struct vhost_dev *dev, + struct list_head *head, + struct vhost_msg_node *node); +struct vhost_msg_node *vhost_dequeue_msg(struct vhost_dev *dev, + struct list_head *head); +unsigned int vhost_chr_poll(struct file *file, struct vhost_dev *dev, + poll_table *wait); +ssize_t vhost_chr_read_iter(struct vhost_dev *dev, struct iov_iter *to, + int noblock); +ssize_t vhost_chr_write_iter(struct vhost_dev *dev, + struct iov_iter *from); +int vhost_init_device_iotlb(struct vhost_dev *d, bool enabled); #define vq_err(vq, fmt, ...) do { \ pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \ diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c new file mode 100644 index 0000000..0ddf3a2 --- /dev/null +++ b/drivers/vhost/vsock.c @@ -0,0 +1,719 @@ +/* + * vhost transport for vsock + * + * Copyright (C) 2013-2015 Red Hat, Inc. + * Author: Asias He <asias@redhat.com> + * Stefan Hajnoczi <stefanha@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. + */ +#include <linux/miscdevice.h> +#include <linux/atomic.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/vmalloc.h> +#include <net/sock.h> +#include <linux/virtio_vsock.h> +#include <linux/vhost.h> + +#include <net/af_vsock.h> +#include "vhost.h" + +#define VHOST_VSOCK_DEFAULT_HOST_CID 2 + +enum { + VHOST_VSOCK_FEATURES = VHOST_FEATURES, +}; + +/* Used to track all the vhost_vsock instances on the system. */ +static DEFINE_SPINLOCK(vhost_vsock_lock); +static LIST_HEAD(vhost_vsock_list); + +struct vhost_vsock { + struct vhost_dev dev; + struct vhost_virtqueue vqs[2]; + + /* Link to global vhost_vsock_list, protected by vhost_vsock_lock */ + struct list_head list; + + struct vhost_work send_pkt_work; + spinlock_t send_pkt_list_lock; + struct list_head send_pkt_list; /* host->guest pending packets */ + + atomic_t queued_replies; + + u32 guest_cid; +}; + +static u32 vhost_transport_get_local_cid(void) +{ + return VHOST_VSOCK_DEFAULT_HOST_CID; +} + +static struct vhost_vsock *vhost_vsock_get(u32 guest_cid) +{ + struct vhost_vsock *vsock; + + spin_lock_bh(&vhost_vsock_lock); + list_for_each_entry(vsock, &vhost_vsock_list, list) { + u32 other_cid = vsock->guest_cid; + + /* Skip instances that have no CID yet */ + if (other_cid == 0) + continue; + + if (other_cid == guest_cid) { + spin_unlock_bh(&vhost_vsock_lock); + return vsock; + } + } + spin_unlock_bh(&vhost_vsock_lock); + + return NULL; +} + +static void +vhost_transport_do_send_pkt(struct vhost_vsock *vsock, + struct vhost_virtqueue *vq) +{ + struct vhost_virtqueue *tx_vq = &vsock->vqs[VSOCK_VQ_TX]; + bool added = false; + bool restart_tx = false; + + mutex_lock(&vq->mutex); + + if (!vq->private_data) + goto out; + + /* Avoid further vmexits, we're already processing the virtqueue */ + vhost_disable_notify(&vsock->dev, vq); + + for (;;) { + struct virtio_vsock_pkt *pkt; + struct iov_iter iov_iter; + unsigned out, in; + size_t nbytes; + size_t len; + int head; + + spin_lock_bh(&vsock->send_pkt_list_lock); + if (list_empty(&vsock->send_pkt_list)) { + spin_unlock_bh(&vsock->send_pkt_list_lock); + vhost_enable_notify(&vsock->dev, vq); + break; + } + + pkt = list_first_entry(&vsock->send_pkt_list, + struct virtio_vsock_pkt, list); + list_del_init(&pkt->list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (head < 0) { + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + break; + } + + if (head == vq->num) { + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + /* We cannot finish yet if more buffers snuck in while + * re-enabling notify. + */ + if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { + vhost_disable_notify(&vsock->dev, vq); + continue; + } + break; + } + + if (out) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Expected 0 output buffers, got %u\n", out); + break; + } + + len = iov_length(&vq->iov[out], in); + iov_iter_init(&iov_iter, READ, &vq->iov[out], in, len); + + nbytes = copy_to_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); + if (nbytes != sizeof(pkt->hdr)) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Faulted on copying pkt hdr\n"); + break; + } + + nbytes = copy_to_iter(pkt->buf, pkt->len, &iov_iter); + if (nbytes != pkt->len) { + virtio_transport_free_pkt(pkt); + vq_err(vq, "Faulted on copying pkt buf\n"); + break; + } + + vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); + added = true; + + if (pkt->reply) { + int val; + + val = atomic_dec_return(&vsock->queued_replies); + + /* Do we have resources to resume tx processing? */ + if (val + 1 == tx_vq->num) + restart_tx = true; + } + + virtio_transport_free_pkt(pkt); + } + if (added) + vhost_signal(&vsock->dev, vq); + +out: + mutex_unlock(&vq->mutex); + + if (restart_tx) + vhost_poll_queue(&tx_vq->poll); +} + +static void vhost_transport_send_pkt_work(struct vhost_work *work) +{ + struct vhost_virtqueue *vq; + struct vhost_vsock *vsock; + + vsock = container_of(work, struct vhost_vsock, send_pkt_work); + vq = &vsock->vqs[VSOCK_VQ_RX]; + + vhost_transport_do_send_pkt(vsock, vq); +} + +static int +vhost_transport_send_pkt(struct virtio_vsock_pkt *pkt) +{ + struct vhost_vsock *vsock; + struct vhost_virtqueue *vq; + int len = pkt->len; + + /* Find the vhost_vsock according to guest context id */ + vsock = vhost_vsock_get(le64_to_cpu(pkt->hdr.dst_cid)); + if (!vsock) { + virtio_transport_free_pkt(pkt); + return -ENODEV; + } + + vq = &vsock->vqs[VSOCK_VQ_RX]; + + if (pkt->reply) + atomic_inc(&vsock->queued_replies); + + spin_lock_bh(&vsock->send_pkt_list_lock); + list_add_tail(&pkt->list, &vsock->send_pkt_list); + spin_unlock_bh(&vsock->send_pkt_list_lock); + + vhost_work_queue(&vsock->dev, &vsock->send_pkt_work); + return len; +} + +static struct virtio_vsock_pkt * +vhost_vsock_alloc_pkt(struct vhost_virtqueue *vq, + unsigned int out, unsigned int in) +{ + struct virtio_vsock_pkt *pkt; + struct iov_iter iov_iter; + size_t nbytes; + size_t len; + + if (in != 0) { + vq_err(vq, "Expected 0 input buffers, got %u\n", in); + return NULL; + } + + pkt = kzalloc(sizeof(*pkt), GFP_KERNEL); + if (!pkt) + return NULL; + + len = iov_length(vq->iov, out); + iov_iter_init(&iov_iter, WRITE, vq->iov, out, len); + + nbytes = copy_from_iter(&pkt->hdr, sizeof(pkt->hdr), &iov_iter); + if (nbytes != sizeof(pkt->hdr)) { + vq_err(vq, "Expected %zu bytes for pkt->hdr, got %zu bytes\n", + sizeof(pkt->hdr), nbytes); + kfree(pkt); + return NULL; + } + + if (le16_to_cpu(pkt->hdr.type) == VIRTIO_VSOCK_TYPE_STREAM) + pkt->len = le32_to_cpu(pkt->hdr.len); + + /* No payload */ + if (!pkt->len) + return pkt; + + /* The pkt is too big */ + if (pkt->len > VIRTIO_VSOCK_MAX_PKT_BUF_SIZE) { + kfree(pkt); + return NULL; + } + + pkt->buf = kmalloc(pkt->len, GFP_KERNEL); + if (!pkt->buf) { + kfree(pkt); + return NULL; + } + + nbytes = copy_from_iter(pkt->buf, pkt->len, &iov_iter); + if (nbytes != pkt->len) { + vq_err(vq, "Expected %u byte payload, got %zu bytes\n", + pkt->len, nbytes); + virtio_transport_free_pkt(pkt); + return NULL; + } + + return pkt; +} + +/* Is there space left for replies to rx packets? */ +static bool vhost_vsock_more_replies(struct vhost_vsock *vsock) +{ + struct vhost_virtqueue *vq = &vsock->vqs[VSOCK_VQ_TX]; + int val; + + smp_rmb(); /* paired with atomic_inc() and atomic_dec_return() */ + val = atomic_read(&vsock->queued_replies); + + return val < vq->num; +} + +static void vhost_vsock_handle_tx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, + dev); + struct virtio_vsock_pkt *pkt; + int head; + unsigned int out, in; + bool added = false; + + mutex_lock(&vq->mutex); + + if (!vq->private_data) + goto out; + + vhost_disable_notify(&vsock->dev, vq); + for (;;) { + if (!vhost_vsock_more_replies(vsock)) { + /* Stop tx until the device processes already + * pending replies. Leave tx virtqueue + * callbacks disabled. + */ + goto no_more_replies; + } + + head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (head < 0) + break; + + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&vsock->dev, vq))) { + vhost_disable_notify(&vsock->dev, vq); + continue; + } + break; + } + + pkt = vhost_vsock_alloc_pkt(vq, out, in); + if (!pkt) { + vq_err(vq, "Faulted on pkt\n"); + continue; + } + + /* Only accept correctly addressed packets */ + if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid) + virtio_transport_recv_pkt(pkt); + else + virtio_transport_free_pkt(pkt); + + vhost_add_used(vq, head, sizeof(pkt->hdr) + pkt->len); + added = true; + } + +no_more_replies: + if (added) + vhost_signal(&vsock->dev, vq); + +out: + mutex_unlock(&vq->mutex); +} + +static void vhost_vsock_handle_rx_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock, + dev); + + vhost_transport_do_send_pkt(vsock, vq); +} + +static int vhost_vsock_start(struct vhost_vsock *vsock) +{ + size_t i; + int ret; + + mutex_lock(&vsock->dev.mutex); + + ret = vhost_dev_check_owner(&vsock->dev); + if (ret) + goto err; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + + if (!vhost_vq_access_ok(vq)) { + ret = -EFAULT; + mutex_unlock(&vq->mutex); + goto err_vq; + } + + if (!vq->private_data) { + vq->private_data = vsock; + vhost_vq_init_access(vq); + } + + mutex_unlock(&vq->mutex); + } + + mutex_unlock(&vsock->dev.mutex); + return 0; + +err_vq: + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + vq->private_data = NULL; + mutex_unlock(&vq->mutex); + } +err: + mutex_unlock(&vsock->dev.mutex); + return ret; +} + +static int vhost_vsock_stop(struct vhost_vsock *vsock) +{ + size_t i; + int ret; + + mutex_lock(&vsock->dev.mutex); + + ret = vhost_dev_check_owner(&vsock->dev); + if (ret) + goto err; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + struct vhost_virtqueue *vq = &vsock->vqs[i]; + + mutex_lock(&vq->mutex); + vq->private_data = NULL; + mutex_unlock(&vq->mutex); + } + +err: + mutex_unlock(&vsock->dev.mutex); + return ret; +} + +static void vhost_vsock_free(struct vhost_vsock *vsock) +{ + kvfree(vsock); +} + +static int vhost_vsock_dev_open(struct inode *inode, struct file *file) +{ + struct vhost_virtqueue **vqs; + struct vhost_vsock *vsock; + int ret; + + /* This struct is large and allocation could fail, fall back to vmalloc + * if there is no other way. + */ + vsock = kzalloc(sizeof(*vsock), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT); + if (!vsock) { + vsock = vmalloc(sizeof(*vsock)); + if (!vsock) + return -ENOMEM; + } + + vqs = kmalloc_array(ARRAY_SIZE(vsock->vqs), sizeof(*vqs), GFP_KERNEL); + if (!vqs) { + ret = -ENOMEM; + goto out; + } + + atomic_set(&vsock->queued_replies, 0); + + vqs[VSOCK_VQ_TX] = &vsock->vqs[VSOCK_VQ_TX]; + vqs[VSOCK_VQ_RX] = &vsock->vqs[VSOCK_VQ_RX]; + vsock->vqs[VSOCK_VQ_TX].handle_kick = vhost_vsock_handle_tx_kick; + vsock->vqs[VSOCK_VQ_RX].handle_kick = vhost_vsock_handle_rx_kick; + + vhost_dev_init(&vsock->dev, vqs, ARRAY_SIZE(vsock->vqs)); + + file->private_data = vsock; + spin_lock_init(&vsock->send_pkt_list_lock); + INIT_LIST_HEAD(&vsock->send_pkt_list); + vhost_work_init(&vsock->send_pkt_work, vhost_transport_send_pkt_work); + + spin_lock_bh(&vhost_vsock_lock); + list_add_tail(&vsock->list, &vhost_vsock_list); + spin_unlock_bh(&vhost_vsock_lock); + return 0; + +out: + vhost_vsock_free(vsock); + return ret; +} + +static void vhost_vsock_flush(struct vhost_vsock *vsock) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) + if (vsock->vqs[i].handle_kick) + vhost_poll_flush(&vsock->vqs[i].poll); + vhost_work_flush(&vsock->dev, &vsock->send_pkt_work); +} + +static void vhost_vsock_reset_orphans(struct sock *sk) +{ + struct vsock_sock *vsk = vsock_sk(sk); + + /* vmci_transport.c doesn't take sk_lock here either. At least we're + * under vsock_table_lock so the sock cannot disappear while we're + * executing. + */ + + if (!vhost_vsock_get(vsk->local_addr.svm_cid)) { + sock_set_flag(sk, SOCK_DONE); + vsk->peer_shutdown = SHUTDOWN_MASK; + sk->sk_state = SS_UNCONNECTED; + sk->sk_err = ECONNRESET; + sk->sk_error_report(sk); + } +} + +static int vhost_vsock_dev_release(struct inode *inode, struct file *file) +{ + struct vhost_vsock *vsock = file->private_data; + + spin_lock_bh(&vhost_vsock_lock); + list_del(&vsock->list); + spin_unlock_bh(&vhost_vsock_lock); + + /* Iterating over all connections for all CIDs to find orphans is + * inefficient. Room for improvement here. */ + vsock_for_each_connected_socket(vhost_vsock_reset_orphans); + + vhost_vsock_stop(vsock); + vhost_vsock_flush(vsock); + vhost_dev_stop(&vsock->dev); + + spin_lock_bh(&vsock->send_pkt_list_lock); + while (!list_empty(&vsock->send_pkt_list)) { + struct virtio_vsock_pkt *pkt; + + pkt = list_first_entry(&vsock->send_pkt_list, + struct virtio_vsock_pkt, list); + list_del_init(&pkt->list); + virtio_transport_free_pkt(pkt); + } + spin_unlock_bh(&vsock->send_pkt_list_lock); + + vhost_dev_cleanup(&vsock->dev, false); + kfree(vsock->dev.vqs); + vhost_vsock_free(vsock); + return 0; +} + +static int vhost_vsock_set_cid(struct vhost_vsock *vsock, u64 guest_cid) +{ + struct vhost_vsock *other; + + /* Refuse reserved CIDs */ + if (guest_cid <= VMADDR_CID_HOST || + guest_cid == U32_MAX) + return -EINVAL; + + /* 64-bit CIDs are not yet supported */ + if (guest_cid > U32_MAX) + return -EINVAL; + + /* Refuse if CID is already in use */ + other = vhost_vsock_get(guest_cid); + if (other && other != vsock) + return -EADDRINUSE; + + spin_lock_bh(&vhost_vsock_lock); + vsock->guest_cid = guest_cid; + spin_unlock_bh(&vhost_vsock_lock); + + return 0; +} + +static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features) +{ + struct vhost_virtqueue *vq; + int i; + + if (features & ~VHOST_VSOCK_FEATURES) + return -EOPNOTSUPP; + + mutex_lock(&vsock->dev.mutex); + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&vsock->dev)) { + mutex_unlock(&vsock->dev.mutex); + return -EFAULT; + } + + for (i = 0; i < ARRAY_SIZE(vsock->vqs); i++) { + vq = &vsock->vqs[i]; + mutex_lock(&vq->mutex); + vq->acked_features = features; + mutex_unlock(&vq->mutex); + } + mutex_unlock(&vsock->dev.mutex); + return 0; +} + +static long vhost_vsock_dev_ioctl(struct file *f, unsigned int ioctl, + unsigned long arg) +{ + struct vhost_vsock *vsock = f->private_data; + void __user *argp = (void __user *)arg; + u64 guest_cid; + u64 features; + int start; + int r; + + switch (ioctl) { + case VHOST_VSOCK_SET_GUEST_CID: + if (copy_from_user(&guest_cid, argp, sizeof(guest_cid))) + return -EFAULT; + return vhost_vsock_set_cid(vsock, guest_cid); + case VHOST_VSOCK_SET_RUNNING: + if (copy_from_user(&start, argp, sizeof(start))) + return -EFAULT; + if (start) + return vhost_vsock_start(vsock); + else + return vhost_vsock_stop(vsock); + case VHOST_GET_FEATURES: + features = VHOST_VSOCK_FEATURES; + if (copy_to_user(argp, &features, sizeof(features))) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, argp, sizeof(features))) + return -EFAULT; + return vhost_vsock_set_features(vsock, features); + default: + mutex_lock(&vsock->dev.mutex); + r = vhost_dev_ioctl(&vsock->dev, ioctl, argp); + if (r == -ENOIOCTLCMD) + r = vhost_vring_ioctl(&vsock->dev, ioctl, argp); + else + vhost_vsock_flush(vsock); + mutex_unlock(&vsock->dev.mutex); + return r; + } +} + +static const struct file_operations vhost_vsock_fops = { + .owner = THIS_MODULE, + .open = vhost_vsock_dev_open, + .release = vhost_vsock_dev_release, + .llseek = noop_llseek, + .unlocked_ioctl = vhost_vsock_dev_ioctl, +}; + +static struct miscdevice vhost_vsock_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vhost-vsock", + .fops = &vhost_vsock_fops, +}; + +static struct virtio_transport vhost_transport = { + .transport = { + .get_local_cid = vhost_transport_get_local_cid, + + .init = virtio_transport_do_socket_init, + .destruct = virtio_transport_destruct, + .release = virtio_transport_release, + .connect = virtio_transport_connect, + .shutdown = virtio_transport_shutdown, + + .dgram_enqueue = virtio_transport_dgram_enqueue, + .dgram_dequeue = virtio_transport_dgram_dequeue, + .dgram_bind = virtio_transport_dgram_bind, + .dgram_allow = virtio_transport_dgram_allow, + + .stream_enqueue = virtio_transport_stream_enqueue, + .stream_dequeue = virtio_transport_stream_dequeue, + .stream_has_data = virtio_transport_stream_has_data, + .stream_has_space = virtio_transport_stream_has_space, + .stream_rcvhiwat = virtio_transport_stream_rcvhiwat, + .stream_is_active = virtio_transport_stream_is_active, + .stream_allow = virtio_transport_stream_allow, + + .notify_poll_in = virtio_transport_notify_poll_in, + .notify_poll_out = virtio_transport_notify_poll_out, + .notify_recv_init = virtio_transport_notify_recv_init, + .notify_recv_pre_block = virtio_transport_notify_recv_pre_block, + .notify_recv_pre_dequeue = virtio_transport_notify_recv_pre_dequeue, + .notify_recv_post_dequeue = virtio_transport_notify_recv_post_dequeue, + .notify_send_init = virtio_transport_notify_send_init, + .notify_send_pre_block = virtio_transport_notify_send_pre_block, + .notify_send_pre_enqueue = virtio_transport_notify_send_pre_enqueue, + .notify_send_post_enqueue = virtio_transport_notify_send_post_enqueue, + + .set_buffer_size = virtio_transport_set_buffer_size, + .set_min_buffer_size = virtio_transport_set_min_buffer_size, + .set_max_buffer_size = virtio_transport_set_max_buffer_size, + .get_buffer_size = virtio_transport_get_buffer_size, + .get_min_buffer_size = virtio_transport_get_min_buffer_size, + .get_max_buffer_size = virtio_transport_get_max_buffer_size, + }, + + .send_pkt = vhost_transport_send_pkt, +}; + +static int __init vhost_vsock_init(void) +{ + int ret; + + ret = vsock_core_init(&vhost_transport.transport); + if (ret < 0) + return ret; + return misc_register(&vhost_vsock_misc); +}; + +static void __exit vhost_vsock_exit(void) +{ + misc_deregister(&vhost_vsock_misc); + vsock_core_exit(); +}; + +module_init(vhost_vsock_init); +module_exit(vhost_vsock_exit); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Asias He"); +MODULE_DESCRIPTION("vhost transport for vsock "); diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 888d5f8..4e7003d 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -207,6 +207,8 @@ static unsigned leak_balloon(struct virtio_balloon *vb, size_t num) num = min(num, ARRAY_SIZE(vb->pfns)); mutex_lock(&vb->balloon_lock); + /* We can't release more pages than taken */ + num = min(num, (size_t)vb->num_pages); for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns += VIRTIO_BALLOON_PAGES_PER_PAGE) { page = balloon_page_dequeue(vb_dev_info); diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index ca6bfdd..114a0c8 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -117,7 +117,10 @@ struct vring_virtqueue { #define to_vvq(_vq) container_of(_vq, struct vring_virtqueue, vq) /* - * The interaction between virtio and a possible IOMMU is a mess. + * Modern virtio devices have feature bits to specify whether they need a + * quirk and bypass the IOMMU. If not there, just use the DMA API. + * + * If there, the interaction between virtio and DMA API is messy. * * On most systems with virtio, physical addresses match bus addresses, * and it doesn't particularly matter whether we use the DMA API. @@ -133,10 +136,18 @@ struct vring_virtqueue { * * For the time being, we preserve historic behavior and bypass the DMA * API. + * + * TODO: install a per-device DMA ops structure that does the right thing + * taking into account all the above quirks, and use the DMA API + * unconditionally on data path. */ static bool vring_use_dma_api(struct virtio_device *vdev) { + if (!virtio_has_iommu_quirk(vdev)) + return true; + + /* Otherwise, we are left to guess. */ /* * In theory, it's possible to have a buggy QEMU-supposed * emulated Q35 IOMMU and Xen enabled at the same time. On @@ -1099,6 +1110,8 @@ void vring_transport_features(struct virtio_device *vdev) break; case VIRTIO_F_VERSION_1: break; + case VIRTIO_F_IOMMU_PLATFORM: + break; default: /* We don't understand this bit. */ __virtio_clear_bit(vdev, i); |