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Diffstat (limited to 'arch/um/drivers/virtio_uml.c')
-rw-r--r--arch/um/drivers/virtio_uml.c153
1 files changed, 131 insertions, 22 deletions
diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
index 023ced2250ea..be54d368e73d 100644
--- a/arch/um/drivers/virtio_uml.c
+++ b/arch/um/drivers/virtio_uml.c
@@ -26,6 +26,7 @@
#include <linux/virtio.h>
#include <linux/virtio_config.h>
#include <linux/virtio_ring.h>
+#include <linux/time-internal.h>
#include <shared/as-layout.h>
#include <irq_kern.h>
#include <init.h>
@@ -53,6 +54,7 @@ struct virtio_uml_device {
struct virtio_device vdev;
struct platform_device *pdev;
+ spinlock_t sock_lock;
int sock, req_fd;
u64 features;
u64 protocol_features;
@@ -63,6 +65,11 @@ struct virtio_uml_device {
struct virtio_uml_vq_info {
int kick_fd, call_fd;
char name[32];
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ struct virtqueue *vq;
+ vq_callback_t *callback;
+ struct time_travel_event defer;
+#endif
};
extern unsigned long long physmem_size, highmem;
@@ -117,10 +124,27 @@ static int vhost_user_recv_header(int fd, struct vhost_user_msg *msg)
static int vhost_user_recv(struct virtio_uml_device *vu_dev,
int fd, struct vhost_user_msg *msg,
- size_t max_payload_size)
+ size_t max_payload_size, bool wait)
{
size_t size;
- int rc = vhost_user_recv_header(fd, msg);
+ int rc;
+
+ /*
+ * In virtio time-travel mode, we're handling all the vhost-user
+ * FDs by polling them whenever appropriate. However, we may get
+ * into a situation where we're sending out an interrupt message
+ * to a device (e.g. a net device) and need to handle a simulation
+ * time message while doing so, e.g. one that tells us to update
+ * our idea of how long we can run without scheduling.
+ *
+ * Thus, we need to not just read() from the given fd, but need
+ * to also handle messages for the simulation time - this function
+ * does that for us while waiting for the given fd to be readable.
+ */
+ if (wait)
+ time_travel_wait_readable(fd);
+
+ rc = vhost_user_recv_header(fd, msg);
if (rc == -ECONNRESET && vu_dev->registered) {
struct virtio_uml_platform_data *pdata;
@@ -142,7 +166,8 @@ static int vhost_user_recv_resp(struct virtio_uml_device *vu_dev,
struct vhost_user_msg *msg,
size_t max_payload_size)
{
- int rc = vhost_user_recv(vu_dev, vu_dev->sock, msg, max_payload_size);
+ int rc = vhost_user_recv(vu_dev, vu_dev->sock, msg,
+ max_payload_size, true);
if (rc)
return rc;
@@ -172,7 +197,8 @@ static int vhost_user_recv_req(struct virtio_uml_device *vu_dev,
struct vhost_user_msg *msg,
size_t max_payload_size)
{
- int rc = vhost_user_recv(vu_dev, vu_dev->req_fd, msg, max_payload_size);
+ int rc = vhost_user_recv(vu_dev, vu_dev->req_fd, msg,
+ max_payload_size, false);
if (rc)
return rc;
@@ -189,6 +215,7 @@ static int vhost_user_send(struct virtio_uml_device *vu_dev,
int *fds, size_t num_fds)
{
size_t size = sizeof(msg->header) + msg->header.size;
+ unsigned long flags;
bool request_ack;
int rc;
@@ -207,24 +234,28 @@ static int vhost_user_send(struct virtio_uml_device *vu_dev,
if (request_ack)
msg->header.flags |= VHOST_USER_FLAG_NEED_REPLY;
+ spin_lock_irqsave(&vu_dev->sock_lock, flags);
rc = full_sendmsg_fds(vu_dev->sock, msg, size, fds, num_fds);
if (rc < 0)
- return rc;
+ goto out;
if (request_ack) {
uint64_t status;
rc = vhost_user_recv_u64(vu_dev, &status);
if (rc)
- return rc;
+ goto out;
if (status) {
vu_err(vu_dev, "slave reports error: %llu\n", status);
- return -EIO;
+ rc = -EIO;
+ goto out;
}
}
- return 0;
+out:
+ spin_unlock_irqrestore(&vu_dev->sock_lock, flags);
+ return rc;
}
static int vhost_user_send_no_payload(struct virtio_uml_device *vu_dev,
@@ -324,6 +355,7 @@ static void vhost_user_reply(struct virtio_uml_device *vu_dev,
static irqreturn_t vu_req_interrupt(int irq, void *data)
{
struct virtio_uml_device *vu_dev = data;
+ struct virtqueue *vq;
int response = 1;
struct {
struct vhost_user_msg msg;
@@ -343,6 +375,15 @@ static irqreturn_t vu_req_interrupt(int irq, void *data)
virtio_config_changed(&vu_dev->vdev);
response = 0;
break;
+ case VHOST_USER_SLAVE_VRING_CALL:
+ virtio_device_for_each_vq((&vu_dev->vdev), vq) {
+ if (vq->index == msg.msg.payload.vring_state.index) {
+ response = 0;
+ vring_interrupt(0 /* ignored */, vq);
+ break;
+ }
+ }
+ break;
case VHOST_USER_SLAVE_IOTLB_MSG:
/* not supported - VIRTIO_F_IOMMU_PLATFORM */
case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
@@ -684,6 +725,17 @@ static bool vu_notify(struct virtqueue *vq)
const uint64_t n = 1;
int rc;
+ time_travel_propagate_time();
+
+ if (info->kick_fd < 0) {
+ struct virtio_uml_device *vu_dev;
+
+ vu_dev = to_virtio_uml_device(vq->vdev);
+
+ return vhost_user_set_vring_state(vu_dev, VHOST_USER_VRING_KICK,
+ vq->index, 0) == 0;
+ }
+
do {
rc = os_write_file(info->kick_fd, &n, sizeof(n));
} while (rc == -EINTR);
@@ -749,10 +801,13 @@ static void vu_del_vq(struct virtqueue *vq)
{
struct virtio_uml_vq_info *info = vq->priv;
- um_free_irq(VIRTIO_IRQ, vq);
+ if (info->call_fd >= 0) {
+ um_free_irq(VIRTIO_IRQ, vq);
+ os_close_file(info->call_fd);
+ }
- os_close_file(info->call_fd);
- os_close_file(info->kick_fd);
+ if (info->kick_fd >= 0)
+ os_close_file(info->kick_fd);
vring_del_virtqueue(vq);
kfree(info);
@@ -782,6 +837,15 @@ static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev,
int call_fds[2];
int rc;
+ /* no call FD needed/desired in this case */
+ if (vu_dev->protocol_features &
+ BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
+ vu_dev->protocol_features &
+ BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
+ info->call_fd = -1;
+ return 0;
+ }
+
/* Use a pipe for call fd, since SIGIO is not supported for eventfd */
rc = os_pipe(call_fds, true, true);
if (rc < 0)
@@ -810,6 +874,23 @@ out:
return rc;
}
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+static void vu_defer_irq_handle(struct time_travel_event *d)
+{
+ struct virtio_uml_vq_info *info;
+
+ info = container_of(d, struct virtio_uml_vq_info, defer);
+ info->callback(info->vq);
+}
+
+static void vu_defer_irq_callback(struct virtqueue *vq)
+{
+ struct virtio_uml_vq_info *info = vq->priv;
+
+ time_travel_add_irq_event(&info->defer);
+}
+#endif
+
static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
unsigned index, vq_callback_t *callback,
const char *name, bool ctx)
@@ -829,6 +910,19 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
snprintf(info->name, sizeof(info->name), "%s.%d-%s", pdev->name,
pdev->id, name);
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ /*
+ * When we get an interrupt, we must bounce it through the simulation
+ * calendar (the simtime device), except for the simtime device itself
+ * since that's part of the simulation control.
+ */
+ if (time_travel_mode == TT_MODE_EXTERNAL && callback) {
+ info->callback = callback;
+ callback = vu_defer_irq_callback;
+ time_travel_set_event_fn(&info->defer, vu_defer_irq_handle);
+ }
+#endif
+
vq = vring_create_virtqueue(index, num, PAGE_SIZE, vdev, true, true,
ctx, vu_notify, callback, info->name);
if (!vq) {
@@ -837,11 +931,19 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
}
vq->priv = info;
num = virtqueue_get_vring_size(vq);
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+ info->vq = vq;
+#endif
- rc = os_eventfd(0, 0);
- if (rc < 0)
- goto error_kick;
- info->kick_fd = rc;
+ if (vu_dev->protocol_features &
+ BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS)) {
+ info->kick_fd = -1;
+ } else {
+ rc = os_eventfd(0, 0);
+ if (rc < 0)
+ goto error_kick;
+ info->kick_fd = rc;
+ }
rc = vu_setup_vq_call_fd(vu_dev, vq);
if (rc)
@@ -866,10 +968,13 @@ static struct virtqueue *vu_setup_vq(struct virtio_device *vdev,
return vq;
error_setup:
- um_free_irq(VIRTIO_IRQ, vq);
- os_close_file(info->call_fd);
+ if (info->call_fd >= 0) {
+ um_free_irq(VIRTIO_IRQ, vq);
+ os_close_file(info->call_fd);
+ }
error_call:
- os_close_file(info->kick_fd);
+ if (info->kick_fd >= 0)
+ os_close_file(info->kick_fd);
error_kick:
vring_del_virtqueue(vq);
error_create:
@@ -908,10 +1013,12 @@ static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs,
list_for_each_entry(vq, &vdev->vqs, list) {
struct virtio_uml_vq_info *info = vq->priv;
- rc = vhost_user_set_vring_kick(vu_dev, vq->index,
- info->kick_fd);
- if (rc)
- goto error_setup;
+ if (info->kick_fd >= 0) {
+ rc = vhost_user_set_vring_kick(vu_dev, vq->index,
+ info->kick_fd);
+ if (rc)
+ goto error_setup;
+ }
rc = vhost_user_set_vring_enable(vu_dev, vq->index, true);
if (rc)
@@ -1008,6 +1115,8 @@ static int virtio_uml_probe(struct platform_device *pdev)
return rc;
vu_dev->sock = rc;
+ spin_lock_init(&vu_dev->sock_lock);
+
rc = vhost_user_init(vu_dev);
if (rc)
goto error_init;
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 20:02:42 +0000