diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 0917f8443c2859d56e86fa62b6c068e53d328b45..96ab7026b037d490e933cad5ef42b016ea67fd89 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -62,9 +62,12 @@ config NR_CPUS
source "arch/$(HEADER_ARCH)/um/Kconfig"
+config FORBID_STATIC_LINK
+ bool
+
config STATIC_LINK
bool "Force a static link"
- default n
+ depends on !FORBID_STATIC_LINK
help
This option gives you the ability to force a static link of UML.
Normally, UML is linked as a shared binary. This is inconvenient for
@@ -73,6 +76,9 @@ config STATIC_LINK
Additionally, this option enables using higher memory spaces (up to
2.75G) for UML.
+ NOTE: This option is incompatible with some networking features which
+ depend on features that require being dynamically loaded (like NSS).
+
config LD_SCRIPT_STATIC
bool
default y
@@ -191,6 +197,7 @@ config UML_TIME_TRAVEL_SUPPORT
prompt "Support time-travel mode (e.g. for test execution)"
# inf-cpu mode is incompatible with the benchmarking
depends on !RAID6_PQ_BENCHMARK
+ depends on !SMP
help
Enable this option to support time travel inside the UML instance.
diff --git a/arch/um/configs/i386_defconfig b/arch/um/configs/i386_defconfig
index 73e98bb57bf510664c0431e158a3914dc18c574a..fb51bd206dbed329e45b885a3de7318bbb4afe7c 100644
--- a/arch/um/configs/i386_defconfig
+++ b/arch/um/configs/i386_defconfig
@@ -26,7 +26,7 @@ CONFIG_SLAB=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
# CONFIG_BLK_DEV_BSG is not set
-CONFIG_IOSCHED_CFQ=m
+CONFIG_IOSCHED_BFQ=m
CONFIG_SSL=y
CONFIG_NULL_CHAN=y
CONFIG_PORT_CHAN=y
diff --git a/arch/um/configs/x86_64_defconfig b/arch/um/configs/x86_64_defconfig
index 3281d7600225be20f2b15e89a6c22115aa6ec08d..477b8731742430a67c4b6eb6084ba79cde72ebc6 100644
--- a/arch/um/configs/x86_64_defconfig
+++ b/arch/um/configs/x86_64_defconfig
@@ -24,7 +24,7 @@ CONFIG_SLAB=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
# CONFIG_BLK_DEV_BSG is not set
-CONFIG_IOSCHED_CFQ=m
+CONFIG_IOSCHED_BFQ=m
CONFIG_SSL=y
CONFIG_NULL_CHAN=y
CONFIG_PORT_CHAN=y
diff --git a/arch/um/drivers/Kconfig b/arch/um/drivers/Kconfig
index 72d4170557820f29d1b951a136d7399e401238e4..9160ead56e33ceeea6163eb81ebce384f357eb82 100644
--- a/arch/um/drivers/Kconfig
+++ b/arch/um/drivers/Kconfig
@@ -234,6 +234,7 @@ config UML_NET_DAEMON
config UML_NET_VECTOR
bool "Vector I/O high performance network devices"
depends on UML_NET
+ select FORBID_STATIC_LINK
help
This User-Mode Linux network driver uses multi-message send
and receive functions. The host running the UML guest must have
@@ -245,6 +246,7 @@ config UML_NET_VECTOR
config UML_NET_VDE
bool "VDE transport (obsolete)"
depends on UML_NET
+ select FORBID_STATIC_LINK
help
This User-Mode Linux network transport allows one or more running
UMLs on a single host to communicate with each other and also
@@ -292,6 +294,7 @@ config UML_NET_MCAST
config UML_NET_PCAP
bool "pcap transport (obsolete)"
depends on UML_NET
+ select FORBID_STATIC_LINK
help
The pcap transport makes a pcap packet stream on the host look
like an ethernet device inside UML. This is useful for making
diff --git a/arch/um/drivers/net_kern.c b/arch/um/drivers/net_kern.c
index 35ebeebfc1a8ad07ee0119bd85d264f21b13bcdd..1802cf4ef5a5a8ef7a16840879f57a806181e67d 100644
--- a/arch/um/drivers/net_kern.c
+++ b/arch/um/drivers/net_kern.c
@@ -266,7 +266,6 @@ static void uml_net_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
- strlcpy(info->version, "42", sizeof(info->version));
}
static const struct ethtool_ops uml_net_ethtool_ops = {
@@ -275,17 +274,6 @@ static const struct ethtool_ops uml_net_ethtool_ops = {
.get_ts_info = ethtool_op_get_ts_info,
};
-static void uml_net_user_timer_expire(struct timer_list *t)
-{
-#ifdef undef
- struct uml_net_private *lp = from_timer(lp, t, tl);
- struct connection *conn = &lp->user;
-
- dprintk(KERN_INFO "uml_net_user_timer_expire [%p]\n", conn);
- do_connect(conn);
-#endif
-}
-
void uml_net_setup_etheraddr(struct net_device *dev, char *str)
{
unsigned char *addr = dev->dev_addr;
@@ -456,7 +444,6 @@ static void eth_configure(int n, void *init, char *mac,
.add_address = transport->user->add_address,
.delete_address = transport->user->delete_address });
- timer_setup(&lp->tl, uml_net_user_timer_expire, 0);
spin_lock_init(&lp->lock);
memcpy(lp->mac, dev->dev_addr, sizeof(lp->mac));
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index 247f95da057b598399ce9170c83f45db5070a2f6..eae8c83364f71826dcececea5a481f7b5831fd9e 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -1592,11 +1592,11 @@ int io_thread(void *arg)
&io_remainder_size,
UBD_REQ_BUFFER_SIZE
);
- if (n < 0) {
- if (n == -EAGAIN) {
+ if (n <= 0) {
+ if (n == -EAGAIN)
ubd_read_poll(-1);
- continue;
- }
+
+ continue;
}
for (count = 0; count < n/sizeof(struct io_thread_req *); count++) {
@@ -1607,7 +1607,9 @@ int io_thread(void *arg)
written = 0;
do {
- res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n);
+ res = os_write_file(kernel_fd,
+ ((char *) io_req_buffer) + written,
+ n - written);
if (res >= 0) {
written += res;
}
diff --git a/arch/um/drivers/vector_kern.c b/arch/um/drivers/vector_kern.c
index e98304d0219ef9f1b67730989c98ec9dbf835c17..8735c468230a5c7802465fcdf9bab3bb9aa9daf6 100644
--- a/arch/um/drivers/vector_kern.c
+++ b/arch/um/drivers/vector_kern.c
@@ -46,7 +46,6 @@
#define DRIVER_NAME "uml-vector"
-#define DRIVER_VERSION "01"
struct vector_cmd_line_arg {
struct list_head list;
int unit;
@@ -198,6 +197,9 @@ static int get_transport_options(struct arglist *def)
long parsed;
int result = 0;
+ if (transport == NULL)
+ return -EINVAL;
+
if (vector != NULL) {
if (kstrtoul(vector, 10, &parsed) == 0) {
if (parsed == 0) {
@@ -1378,7 +1380,6 @@ static void vector_net_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
strlcpy(info->driver, DRIVER_NAME, sizeof(info->driver));
- strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
}
static int vector_net_load_bpf_flash(struct net_device *dev,
diff --git a/arch/um/drivers/vector_user.c b/arch/um/drivers/vector_user.c
index ddcd917be0af8604b77255190ba5074ee7cae8a1..aa28e9eecb7baf098d9158f3fee4c2e21887f96e 100644
--- a/arch/um/drivers/vector_user.c
+++ b/arch/um/drivers/vector_user.c
@@ -221,8 +221,7 @@ static struct vector_fds *user_init_tap_fds(struct arglist *ifspec)
return result;
tap_cleanup:
printk(UM_KERN_ERR "user_init_tap: init failed, error %d", fd);
- if (result != NULL)
- kfree(result);
+ kfree(result);
return NULL;
}
@@ -266,8 +265,7 @@ static struct vector_fds *user_init_hybrid_fds(struct arglist *ifspec)
return result;
hybrid_cleanup:
printk(UM_KERN_ERR "user_init_hybrid: init failed");
- if (result != NULL)
- kfree(result);
+ kfree(result);
return NULL;
}
@@ -344,10 +342,8 @@ static struct vector_fds *user_init_unix_fds(struct arglist *ifspec, int id)
unix_cleanup:
if (fd >= 0)
os_close_file(fd);
- if (remote_addr != NULL)
- kfree(remote_addr);
- if (result != NULL)
- kfree(result);
+ kfree(remote_addr);
+ kfree(result);
return NULL;
}
@@ -382,8 +378,7 @@ static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
return result;
raw_cleanup:
printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err);
- if (result != NULL)
- kfree(result);
+ kfree(result);
return NULL;
}
diff --git a/arch/um/drivers/vhost_user.h b/arch/um/drivers/vhost_user.h
index 45ff5ea22fea5d5d84053b1ab517472628b0d158..6c71b600517746c7309197ea87eb3089666d3210 100644
--- a/arch/um/drivers/vhost_user.h
+++ b/arch/um/drivers/vhost_user.h
@@ -10,9 +10,10 @@
/* Feature bits */
#define VHOST_USER_F_PROTOCOL_FEATURES 30
/* Protocol feature bits */
-#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
-#define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
-#define VHOST_USER_PROTOCOL_F_CONFIG 9
+#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
+#define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
+#define VHOST_USER_PROTOCOL_F_CONFIG 9
+#define VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS 14
/* Vring state index masks */
#define VHOST_USER_VRING_INDEX_MASK 0xff
#define VHOST_USER_VRING_POLL_MASK BIT(8)
@@ -24,7 +25,8 @@
/* Supported protocol features */
#define VHOST_USER_SUPPORTED_PROTOCOL_F (BIT_ULL(VHOST_USER_PROTOCOL_F_REPLY_ACK) | \
BIT_ULL(VHOST_USER_PROTOCOL_F_SLAVE_REQ) | \
- BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG))
+ BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG) | \
+ BIT_ULL(VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS))
enum vhost_user_request {
VHOST_USER_GET_FEATURES = 1,
@@ -52,12 +54,14 @@ enum vhost_user_request {
VHOST_USER_SET_VRING_ENDIAN = 23,
VHOST_USER_GET_CONFIG = 24,
VHOST_USER_SET_CONFIG = 25,
+ VHOST_USER_VRING_KICK = 35,
};
enum vhost_user_slave_request {
VHOST_USER_SLAVE_IOTLB_MSG = 1,
VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
+ VHOST_USER_SLAVE_VRING_CALL = 4,
};
struct vhost_user_header {
diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c
index 023ced2250ea7ef57c274440c752aefb9b6bd67d..be54d368e73dd383ecdfcbe32546eb0bf733cbdc 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 @@ static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev,
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;
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index db7d9d4e30d83b9353d0235d35018a46c999795a..8d435f8a6decdd9e8560f907958e63fb839148a4 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -3,7 +3,6 @@ generic-y += bpf_perf_event.h
generic-y += bug.h
generic-y += compat.h
generic-y += current.h
-generic-y += delay.h
generic-y += device.h
generic-y += emergency-restart.h
generic-y += exec.h
diff --git a/arch/um/include/asm/delay.h b/arch/um/include/asm/delay.h
new file mode 100644
index 0000000000000000000000000000000000000000..56fc2b8f2dd019ec8b75065f2a7f2c791c0c2d7a
--- /dev/null
+++ b/arch/um/include/asm/delay.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __UM_DELAY_H
+#define __UM_DELAY_H
+#include <asm-generic/delay.h>
+#include <linux/time-internal.h>
+
+static inline void um_ndelay(unsigned long nsecs)
+{
+ if (time_travel_mode == TT_MODE_INFCPU ||
+ time_travel_mode == TT_MODE_EXTERNAL) {
+ time_travel_ndelay(nsecs);
+ return;
+ }
+ ndelay(nsecs);
+}
+#undef ndelay
+#define ndelay um_ndelay
+
+static inline void um_udelay(unsigned long usecs)
+{
+ if (time_travel_mode == TT_MODE_INFCPU ||
+ time_travel_mode == TT_MODE_EXTERNAL) {
+ time_travel_ndelay(1000 * usecs);
+ return;
+ }
+ udelay(usecs);
+}
+#undef udelay
+#define udelay um_udelay
+#endif /* __UM_DELAY_H */
diff --git a/arch/um/include/linux/time-internal.h b/arch/um/include/linux/time-internal.h
new file mode 100644
index 0000000000000000000000000000000000000000..f3b03d39a854387e4b6544ff1297bedaa2b0f53a
--- /dev/null
+++ b/arch/um/include/linux/time-internal.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2012 - 2014 Cisco Systems
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ */
+
+#ifndef __TIMER_INTERNAL_H__
+#define __TIMER_INTERNAL_H__
+#include <linux/list.h>
+
+#define TIMER_MULTIPLIER 256
+#define TIMER_MIN_DELTA 500
+
+enum time_travel_mode {
+ TT_MODE_OFF,
+ TT_MODE_BASIC,
+ TT_MODE_INFCPU,
+ TT_MODE_EXTERNAL,
+};
+
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+struct time_travel_event {
+ unsigned long long time;
+ void (*fn)(struct time_travel_event *d);
+ struct list_head list;
+ bool pending, onstack;
+};
+
+extern enum time_travel_mode time_travel_mode;
+
+void time_travel_sleep(unsigned long long duration);
+
+static inline void
+time_travel_set_event_fn(struct time_travel_event *e,
+ void (*fn)(struct time_travel_event *d))
+{
+ e->fn = fn;
+}
+
+void __time_travel_propagate_time(void);
+
+static inline void time_travel_propagate_time(void)
+{
+ if (time_travel_mode == TT_MODE_EXTERNAL)
+ __time_travel_propagate_time();
+}
+
+void __time_travel_wait_readable(int fd);
+
+static inline void time_travel_wait_readable(int fd)
+{
+ if (time_travel_mode == TT_MODE_EXTERNAL)
+ __time_travel_wait_readable(fd);
+}
+
+void time_travel_add_irq_event(struct time_travel_event *e);
+#else
+struct time_travel_event {
+};
+
+#define time_travel_mode TT_MODE_OFF
+
+static inline void time_travel_sleep(unsigned long long duration)
+{
+}
+
+/* this is a macro so the event/function need not exist */
+#define time_travel_set_event_fn(e, fn) do {} while (0)
+
+static inline void time_travel_propagate_time(void)
+{
+}
+
+static inline void time_travel_wait_readable(int fd)
+{
+}
+#endif /* CONFIG_UML_TIME_TRAVEL_SUPPORT */
+
+/*
+ * Without CONFIG_UML_TIME_TRAVEL_SUPPORT this is a linker error if used,
+ * which is intentional since we really shouldn't link it in that case.
+ */
+void time_travel_ndelay(unsigned long nsec);
+#endif /* __TIMER_INTERNAL_H__ */
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index 0f30204b6afa86e4116df23b02d152bb94c27012..f467d28fc0b4903f20870b607c217dc83ada173d 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -181,6 +181,7 @@ extern int os_falloc_punch(int fd, unsigned long long offset, int count);
extern int os_eventfd(unsigned int initval, int flags);
extern int os_sendmsg_fds(int fd, const void *buf, unsigned int len,
const int *fds, unsigned int fds_num);
+int os_poll(unsigned int n, const int *fds);
/* start_up.c */
extern void os_early_checks(void);
diff --git a/arch/um/include/shared/timer-internal.h b/arch/um/include/shared/timer-internal.h
deleted file mode 100644
index 2d2d13c9b46f96246bd06be19a85a610196cc756..0000000000000000000000000000000000000000
--- a/arch/um/include/shared/timer-internal.h
+++ /dev/null
@@ -1,76 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2012 - 2014 Cisco Systems
- * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- */
-
-#ifndef __TIMER_INTERNAL_H__
-#define __TIMER_INTERNAL_H__
-
-#define TIMER_MULTIPLIER 256
-#define TIMER_MIN_DELTA 500
-
-enum time_travel_mode {
- TT_MODE_OFF,
- TT_MODE_BASIC,
- TT_MODE_INFCPU,
-};
-
-enum time_travel_timer_mode {
- TT_TMR_DISABLED,
- TT_TMR_ONESHOT,
- TT_TMR_PERIODIC,
-};
-
-#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
-extern enum time_travel_mode time_travel_mode;
-extern unsigned long long time_travel_time;
-extern enum time_travel_timer_mode time_travel_timer_mode;
-extern unsigned long long time_travel_timer_expiry;
-extern unsigned long long time_travel_timer_interval;
-
-static inline void time_travel_set_time(unsigned long long ns)
-{
- time_travel_time = ns;
-}
-
-static inline void time_travel_set_timer_mode(enum time_travel_timer_mode mode)
-{
- time_travel_timer_mode = mode;
-}
-
-static inline void time_travel_set_timer_expiry(unsigned long long expiry)
-{
- time_travel_timer_expiry = expiry;
-}
-
-static inline void time_travel_set_timer_interval(unsigned long long interval)
-{
- time_travel_timer_interval = interval;
-}
-#else
-#define time_travel_mode TT_MODE_OFF
-#define time_travel_time 0
-#define time_travel_timer_expiry 0
-#define time_travel_timer_interval 0
-
-static inline void time_travel_set_time(unsigned long long ns)
-{
-}
-
-static inline void time_travel_set_timer_mode(enum time_travel_timer_mode mode)
-{
-}
-
-static inline void time_travel_set_timer_expiry(unsigned long long expiry)
-{
-}
-
-static inline void time_travel_set_timer_interval(unsigned long long interval)
-{
-}
-
-#define time_travel_timer_mode TT_TMR_DISABLED
-#endif
-
-#endif
diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c
index 98bdf69e4c2e59445d3ac0dcc1b4f9f99a09bcf4..e4abac6c9727cc274647b47da116c1dfeae4e6d8 100644
--- a/arch/um/kernel/kmsg_dump.c
+++ b/arch/um/kernel/kmsg_dump.c
@@ -9,20 +9,19 @@ static void kmsg_dumper_stdout(struct kmsg_dumper *dumper,
enum kmsg_dump_reason reason)
{
static char line[1024];
-
+ struct console *con;
size_t len = 0;
- bool con_available = false;
/* only dump kmsg when no console is available */
if (!console_trylock())
return;
- if (console_drivers != NULL)
- con_available = true;
+ for_each_console(con)
+ break;
console_unlock();
- if (con_available == true)
+ if (con)
return;
printf("kmsg_dump:\n");
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 56a094182bf50fe0c5534c12be1dea873dfb3fa1..cbe33af2a880525811dfaf2fb9ced4b3527ffd87 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -32,7 +32,7 @@
#include <kern_util.h>
#include <os.h>
#include <skas.h>
-#include <timer-internal.h>
+#include <linux/time-internal.h>
/*
* This is a per-cpu array. A processor only modifies its entry and it only
@@ -203,43 +203,6 @@ void initial_thread_cb(void (*proc)(void *), void *arg)
kmalloc_ok = save_kmalloc_ok;
}
-static void time_travel_sleep(unsigned long long duration)
-{
- unsigned long long next = time_travel_time + duration;
-
- if (time_travel_mode != TT_MODE_INFCPU)
- os_timer_disable();
-
- while (time_travel_timer_mode == TT_TMR_PERIODIC &&
- time_travel_timer_expiry < time_travel_time)
- time_travel_set_timer_expiry(time_travel_timer_expiry +
- time_travel_timer_interval);
-
- if (time_travel_timer_mode != TT_TMR_DISABLED &&
- time_travel_timer_expiry < next) {
- if (time_travel_timer_mode == TT_TMR_ONESHOT)
- time_travel_set_timer_mode(TT_TMR_DISABLED);
- /*
- * In basic mode, time_travel_time will be adjusted in
- * the timer IRQ handler so it works even when the signal
- * comes from the OS timer, see there.
- */
- if (time_travel_mode != TT_MODE_BASIC)
- time_travel_set_time(time_travel_timer_expiry);
-
- deliver_alarm();
- } else {
- time_travel_set_time(next);
- }
-
- if (time_travel_mode != TT_MODE_INFCPU) {
- if (time_travel_timer_mode == TT_TMR_PERIODIC)
- os_timer_set_interval(time_travel_timer_interval);
- else if (time_travel_timer_mode == TT_TMR_ONESHOT)
- os_timer_one_shot(time_travel_timer_expiry - next);
- }
-}
-
static void um_idle_sleep(void)
{
unsigned long long duration = UM_NSEC_PER_SEC;
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c
index 40d90dddf3f1fac28a4108672e3ded49dc7059ab..0a12d5a092177b7f255242025cd11d9c22736d8f 100644
--- a/arch/um/kernel/skas/syscall.c
+++ b/arch/um/kernel/skas/syscall.c
@@ -10,7 +10,7 @@
#include <sysdep/ptrace.h>
#include <sysdep/ptrace_user.h>
#include <sysdep/syscalls.h>
-#include <shared/timer-internal.h>
+#include <linux/time-internal.h>
void handle_syscall(struct uml_pt_regs *r)
{
@@ -24,7 +24,8 @@ void handle_syscall(struct uml_pt_regs *r)
* went to sleep, even if said userspace interacts with the kernel in
* various ways.
*/
- if (time_travel_mode == TT_MODE_INFCPU)
+ if (time_travel_mode == TT_MODE_INFCPU ||
+ time_travel_mode == TT_MODE_EXTERNAL)
schedule();
/* Initialize the syscall number and default return value. */
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c
index 94ea87bd231cb0916b756ac88724a28921b3eff0..25eaa6a0c6583f79e10ab292fa4ac67193f105a4 100644
--- a/arch/um/kernel/time.c
+++ b/arch/um/kernel/time.c
@@ -4,6 +4,7 @@
* Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
* Copyright (C) 2012-2014 Cisco Systems
* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Copyright (C) 2019 Intel Corporation
*/
#include <linux/clockchips.h>
@@ -18,21 +19,484 @@
#include <asm/param.h>
#include <kern_util.h>
#include <os.h>
-#include <timer-internal.h>
+#include <linux/time-internal.h>
+#include <linux/um_timetravel.h>
#include <shared/init.h>
#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
enum time_travel_mode time_travel_mode;
-unsigned long long time_travel_time;
-enum time_travel_timer_mode time_travel_timer_mode;
-unsigned long long time_travel_timer_expiry;
-unsigned long long time_travel_timer_interval;
+EXPORT_SYMBOL_GPL(time_travel_mode);
static bool time_travel_start_set;
static unsigned long long time_travel_start;
-#else
+static unsigned long long time_travel_time;
+static LIST_HEAD(time_travel_events);
+static unsigned long long time_travel_timer_interval;
+static unsigned long long time_travel_next_event;
+static struct time_travel_event time_travel_timer_event;
+static int time_travel_ext_fd = -1;
+static unsigned int time_travel_ext_waiting;
+static bool time_travel_ext_prev_request_valid;
+static unsigned long long time_travel_ext_prev_request;
+static bool time_travel_ext_free_until_valid;
+static unsigned long long time_travel_ext_free_until;
+
+static void time_travel_set_time(unsigned long long ns)
+{
+ if (unlikely(ns < time_travel_time))
+ panic("time-travel: time goes backwards %lld -> %lld\n",
+ time_travel_time, ns);
+ time_travel_time = ns;
+}
+
+enum time_travel_message_handling {
+ TTMH_IDLE,
+ TTMH_POLL,
+ TTMH_READ,
+};
+
+static void time_travel_handle_message(struct um_timetravel_msg *msg,
+ enum time_travel_message_handling mode)
+{
+ struct um_timetravel_msg resp = {
+ .op = UM_TIMETRAVEL_ACK,
+ };
+ int ret;
+
+ /*
+ * Poll outside the locked section (if we're not called to only read
+ * the response) so we can get interrupts for e.g. virtio while we're
+ * here, but then we need to lock to not get interrupted between the
+ * read of the message and write of the ACK.
+ */
+ if (mode != TTMH_READ) {
+ while (os_poll(1, &time_travel_ext_fd) != 0) {
+ if (mode == TTMH_IDLE) {
+ BUG_ON(!irqs_disabled());
+ local_irq_enable();
+ local_irq_disable();
+ }
+ }
+ }
+
+ ret = os_read_file(time_travel_ext_fd, msg, sizeof(*msg));
+
+ if (ret == 0)
+ panic("time-travel external link is broken\n");
+ if (ret != sizeof(*msg))
+ panic("invalid time-travel message - %d bytes\n", ret);
+
+ switch (msg->op) {
+ default:
+ WARN_ONCE(1, "time-travel: unexpected message %lld\n",
+ (unsigned long long)msg->op);
+ break;
+ case UM_TIMETRAVEL_ACK:
+ return;
+ case UM_TIMETRAVEL_RUN:
+ time_travel_set_time(msg->time);
+ break;
+ case UM_TIMETRAVEL_FREE_UNTIL:
+ time_travel_ext_free_until_valid = true;
+ time_travel_ext_free_until = msg->time;
+ break;
+ }
+
+ os_write_file(time_travel_ext_fd, &resp, sizeof(resp));
+}
+
+static u64 time_travel_ext_req(u32 op, u64 time)
+{
+ static int seq;
+ int mseq = ++seq;
+ struct um_timetravel_msg msg = {
+ .op = op,
+ .time = time,
+ .seq = mseq,
+ };
+ unsigned long flags;
+
+ /*
+ * We need to save interrupts here and only restore when we
+ * got the ACK - otherwise we can get interrupted and send
+ * another request while we're still waiting for an ACK, but
+ * the peer doesn't know we got interrupted and will send
+ * the ACKs in the same order as the message, but we'd need
+ * to see them in the opposite order ...
+ *
+ * This wouldn't matter *too* much, but some ACKs carry the
+ * current time (for UM_TIMETRAVEL_GET) and getting another
+ * ACK without a time would confuse us a lot!
+ *
+ * The sequence number assignment that happens here lets us
+ * debug such message handling issues more easily.
+ */
+ local_irq_save(flags);
+ os_write_file(time_travel_ext_fd, &msg, sizeof(msg));
+
+ while (msg.op != UM_TIMETRAVEL_ACK)
+ time_travel_handle_message(&msg, TTMH_READ);
+
+ if (msg.seq != mseq)
+ panic("time-travel: ACK message has different seqno! op=%d, seq=%d != %d time=%lld\n",
+ msg.op, msg.seq, mseq, msg.time);
+
+ if (op == UM_TIMETRAVEL_GET)
+ time_travel_set_time(msg.time);
+ local_irq_restore(flags);
+
+ return msg.time;
+}
+
+void __time_travel_wait_readable(int fd)
+{
+ int fds[2] = { fd, time_travel_ext_fd };
+ int ret;
+
+ if (time_travel_mode != TT_MODE_EXTERNAL)
+ return;
+
+ while ((ret = os_poll(2, fds))) {
+ struct um_timetravel_msg msg;
+
+ if (ret == 1)
+ time_travel_handle_message(&msg, TTMH_READ);
+ }
+}
+EXPORT_SYMBOL_GPL(__time_travel_wait_readable);
+
+static void time_travel_ext_update_request(unsigned long long time)
+{
+ if (time_travel_mode != TT_MODE_EXTERNAL)
+ return;
+
+ /* asked for exactly this time previously */
+ if (time_travel_ext_prev_request_valid &&
+ time == time_travel_ext_prev_request)
+ return;
+
+ time_travel_ext_prev_request = time;
+ time_travel_ext_prev_request_valid = true;
+ time_travel_ext_req(UM_TIMETRAVEL_REQUEST, time);
+}
+
+void __time_travel_propagate_time(void)
+{
+ time_travel_ext_req(UM_TIMETRAVEL_UPDATE, time_travel_time);
+}
+EXPORT_SYMBOL_GPL(__time_travel_propagate_time);
+
+/* returns true if we must do a wait to the simtime device */
+static bool time_travel_ext_request(unsigned long long time)
+{
+ /*
+ * If we received an external sync point ("free until") then we
+ * don't have to request/wait for anything until then, unless
+ * we're already waiting.
+ */
+ if (!time_travel_ext_waiting && time_travel_ext_free_until_valid &&
+ time < time_travel_ext_free_until)
+ return false;
+
+ time_travel_ext_update_request(time);
+ return true;
+}
+
+static void time_travel_ext_wait(bool idle)
+{
+ struct um_timetravel_msg msg = {
+ .op = UM_TIMETRAVEL_ACK,
+ };
+
+ time_travel_ext_prev_request_valid = false;
+ time_travel_ext_waiting++;
+
+ time_travel_ext_req(UM_TIMETRAVEL_WAIT, -1);
+
+ /*
+ * Here we are deep in the idle loop, so we have to break out of the
+ * kernel abstraction in a sense and implement this in terms of the
+ * UML system waiting on the VQ interrupt while sleeping, when we get
+ * the signal it'll call time_travel_ext_vq_notify_done() completing the
+ * call.
+ */
+ while (msg.op != UM_TIMETRAVEL_RUN)
+ time_travel_handle_message(&msg, idle ? TTMH_IDLE : TTMH_POLL);
+
+ time_travel_ext_waiting--;
+
+ /* we might request more stuff while polling - reset when we run */
+ time_travel_ext_prev_request_valid = false;
+}
+
+static void time_travel_ext_get_time(void)
+{
+ time_travel_ext_req(UM_TIMETRAVEL_GET, -1);
+}
+
+static void __time_travel_update_time(unsigned long long ns, bool idle)
+{
+ if (time_travel_mode == TT_MODE_EXTERNAL && time_travel_ext_request(ns))
+ time_travel_ext_wait(idle);
+ else
+ time_travel_set_time(ns);
+}
+
+static struct time_travel_event *time_travel_first_event(void)
+{
+ return list_first_entry_or_null(&time_travel_events,
+ struct time_travel_event,
+ list);
+}
+
+static void __time_travel_add_event(struct time_travel_event *e,
+ unsigned long long time)
+{
+ struct time_travel_event *tmp;
+ bool inserted = false;
+
+ if (WARN(time_travel_mode == TT_MODE_BASIC &&
+ e != &time_travel_timer_event,
+ "only timer events can be handled in basic mode"))
+ return;
+
+ if (e->pending)
+ return;
+
+ e->pending = true;
+ e->time = time;
+
+ list_for_each_entry(tmp, &time_travel_events, list) {
+ /*
+ * Add the new entry before one with higher time,
+ * or if they're equal and both on stack, because
+ * in that case we need to unwind the stack in the
+ * right order, and the later event (timer sleep
+ * or such) must be dequeued first.
+ */
+ if ((tmp->time > e->time) ||
+ (tmp->time == e->time && tmp->onstack && e->onstack)) {
+ list_add_tail(&e->list, &tmp->list);
+ inserted = true;
+ break;
+ }
+ }
+
+ if (!inserted)
+ list_add_tail(&e->list, &time_travel_events);
+
+ tmp = time_travel_first_event();
+ time_travel_ext_update_request(tmp->time);
+ time_travel_next_event = tmp->time;
+}
+
+static void time_travel_add_event(struct time_travel_event *e,
+ unsigned long long time)
+{
+ if (WARN_ON(!e->fn))
+ return;
+
+ __time_travel_add_event(e, time);
+}
+
+void time_travel_periodic_timer(struct time_travel_event *e)
+{
+ time_travel_add_event(&time_travel_timer_event,
+ time_travel_time + time_travel_timer_interval);
+ deliver_alarm();
+}
+
+static void time_travel_deliver_event(struct time_travel_event *e)
+{
+ if (e == &time_travel_timer_event) {
+ /*
+ * deliver_alarm() does the irq_enter/irq_exit
+ * by itself, so must handle it specially here
+ */
+ e->fn(e);
+ } else {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ irq_enter();
+ e->fn(e);
+ irq_exit();
+ local_irq_restore(flags);
+ }
+}
+
+static bool time_travel_del_event(struct time_travel_event *e)
+{
+ if (!e->pending)
+ return false;
+ list_del(&e->list);
+ e->pending = false;
+ return true;
+}
+
+static void time_travel_update_time(unsigned long long next, bool idle)
+{
+ struct time_travel_event ne = {
+ .onstack = true,
+ };
+ struct time_travel_event *e;
+ bool finished = idle;
+
+ /* add it without a handler - we deal with that specifically below */
+ __time_travel_add_event(&ne, next);
+
+ do {
+ e = time_travel_first_event();
+
+ BUG_ON(!e);
+ __time_travel_update_time(e->time, idle);
+
+ /* new events may have been inserted while we were waiting */
+ if (e == time_travel_first_event()) {
+ BUG_ON(!time_travel_del_event(e));
+ BUG_ON(time_travel_time != e->time);
+
+ if (e == &ne) {
+ finished = true;
+ } else {
+ if (e->onstack)
+ panic("On-stack event dequeued outside of the stack! time=%lld, event time=%lld, event=%pS\n",
+ time_travel_time, e->time, e);
+ time_travel_deliver_event(e);
+ }
+ }
+
+ e = time_travel_first_event();
+ if (e)
+ time_travel_ext_update_request(e->time);
+ } while (ne.pending && !finished);
+
+ time_travel_del_event(&ne);
+}
+
+void time_travel_ndelay(unsigned long nsec)
+{
+ time_travel_update_time(time_travel_time + nsec, false);
+}
+EXPORT_SYMBOL(time_travel_ndelay);
+
+void time_travel_add_irq_event(struct time_travel_event *e)
+{
+ BUG_ON(time_travel_mode != TT_MODE_EXTERNAL);
+
+ time_travel_ext_get_time();
+ /*
+ * We could model interrupt latency here, for now just
+ * don't have any latency at all and request the exact
+ * same time (again) to run the interrupt...
+ */
+ time_travel_add_event(e, time_travel_time);
+}
+EXPORT_SYMBOL_GPL(time_travel_add_irq_event);
+
+static void time_travel_oneshot_timer(struct time_travel_event *e)
+{
+ deliver_alarm();
+}
+
+void time_travel_sleep(unsigned long long duration)
+{
+ unsigned long long next = time_travel_time + duration;
+
+ if (time_travel_mode == TT_MODE_BASIC)
+ os_timer_disable();
+
+ time_travel_update_time(next, true);
+
+ if (time_travel_mode == TT_MODE_BASIC &&
+ time_travel_timer_event.pending) {
+ if (time_travel_timer_event.fn == time_travel_periodic_timer) {
+ /*
+ * This is somewhat wrong - we should get the first
+ * one sooner like the os_timer_one_shot() below...
+ */
+ os_timer_set_interval(time_travel_timer_interval);
+ } else {
+ os_timer_one_shot(time_travel_timer_event.time - next);
+ }
+ }
+}
+
+static void time_travel_handle_real_alarm(void)
+{
+ time_travel_set_time(time_travel_next_event);
+
+ time_travel_del_event(&time_travel_timer_event);
+
+ if (time_travel_timer_event.fn == time_travel_periodic_timer)
+ time_travel_add_event(&time_travel_timer_event,
+ time_travel_time +
+ time_travel_timer_interval);
+}
+
+static void time_travel_set_interval(unsigned long long interval)
+{
+ time_travel_timer_interval = interval;
+}
+
+static int time_travel_connect_external(const char *socket)
+{
+ const char *sep;
+ unsigned long long id = (unsigned long long)-1;
+ int rc;
+
+ if ((sep = strchr(socket, ':'))) {
+ char buf[25] = {};
+ if (sep - socket > sizeof(buf) - 1)
+ goto invalid_number;
+
+ memcpy(buf, socket, sep - socket);
+ if (kstrtoull(buf, 0, &id)) {
+invalid_number:
+ panic("time-travel: invalid external ID in string '%s'\n",
+ socket);
+ return -EINVAL;
+ }
+
+ socket = sep + 1;
+ }
+
+ rc = os_connect_socket(socket);
+ if (rc < 0) {
+ panic("time-travel: failed to connect to external socket %s\n",
+ socket);
+ return rc;
+ }
+
+ time_travel_ext_fd = rc;
+
+ time_travel_ext_req(UM_TIMETRAVEL_START, id);
+
+ return 1;
+}
+#else /* CONFIG_UML_TIME_TRAVEL_SUPPORT */
#define time_travel_start_set 0
#define time_travel_start 0
+#define time_travel_time 0
+
+static inline void time_travel_update_time(unsigned long long ns, bool retearly)
+{
+}
+
+static inline void time_travel_handle_real_alarm(void)
+{
+}
+
+static void time_travel_set_interval(unsigned long long interval)
+{
+}
+
+/* fail link if this actually gets used */
+extern u64 time_travel_ext_req(u32 op, u64 time);
+
+/* these are empty macros so the struct/fn need not exist */
+#define time_travel_add_event(e, time) do { } while (0)
+#define time_travel_del_event(e) do { } while (0)
#endif
void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
@@ -48,7 +512,7 @@ void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
* never get any real signals from the OS.
*/
if (time_travel_mode == TT_MODE_BASIC)
- time_travel_set_time(time_travel_timer_expiry);
+ time_travel_handle_real_alarm();
local_irq_save(flags);
do_IRQ(TIMER_IRQ, regs);
@@ -58,9 +522,10 @@ void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
static int itimer_shutdown(struct clock_event_device *evt)
{
if (time_travel_mode != TT_MODE_OFF)
- time_travel_set_timer_mode(TT_TMR_DISABLED);
+ time_travel_del_event(&time_travel_timer_event);
- if (time_travel_mode != TT_MODE_INFCPU)
+ if (time_travel_mode != TT_MODE_INFCPU &&
+ time_travel_mode != TT_MODE_EXTERNAL)
os_timer_disable();
return 0;
@@ -71,12 +536,16 @@ static int itimer_set_periodic(struct clock_event_device *evt)
unsigned long long interval = NSEC_PER_SEC / HZ;
if (time_travel_mode != TT_MODE_OFF) {
- time_travel_set_timer_mode(TT_TMR_PERIODIC);
- time_travel_set_timer_expiry(time_travel_time + interval);
- time_travel_set_timer_interval(interval);
+ time_travel_del_event(&time_travel_timer_event);
+ time_travel_set_event_fn(&time_travel_timer_event,
+ time_travel_periodic_timer);
+ time_travel_set_interval(interval);
+ time_travel_add_event(&time_travel_timer_event,
+ time_travel_time + interval);
}
- if (time_travel_mode != TT_MODE_INFCPU)
+ if (time_travel_mode != TT_MODE_INFCPU &&
+ time_travel_mode != TT_MODE_EXTERNAL)
os_timer_set_interval(interval);
return 0;
@@ -88,11 +557,15 @@ static int itimer_next_event(unsigned long delta,
delta += 1;
if (time_travel_mode != TT_MODE_OFF) {
- time_travel_set_timer_mode(TT_TMR_ONESHOT);
- time_travel_set_timer_expiry(time_travel_time + delta);
+ time_travel_del_event(&time_travel_timer_event);
+ time_travel_set_event_fn(&time_travel_timer_event,
+ time_travel_oneshot_timer);
+ time_travel_add_event(&time_travel_timer_event,
+ time_travel_time + delta);
}
- if (time_travel_mode != TT_MODE_INFCPU)
+ if (time_travel_mode != TT_MODE_INFCPU &&
+ time_travel_mode != TT_MODE_EXTERNAL)
return os_timer_one_shot(delta);
return 0;
@@ -143,8 +616,17 @@ static u64 timer_read(struct clocksource *cs)
* stuck in loops that expect time to move more than the
* exact requested sleep amount, e.g. python's socket server,
* see https://bugs.python.org/issue37026.
+ *
+ * However, don't do that when we're in interrupt or such as
+ * then we might recurse into our own processing, and get to
+ * even more waiting, and that's not good - it messes up the
+ * "what do I do next" and onstack event we use to know when
+ * to return from time_travel_update_time().
*/
- time_travel_set_time(time_travel_time + TIMER_MULTIPLIER);
+ if (!irqs_disabled() && !in_interrupt() && !in_softirq())
+ time_travel_update_time(time_travel_time +
+ TIMER_MULTIPLIER,
+ false);
return time_travel_time / TIMER_MULTIPLIER;
}
@@ -188,6 +670,8 @@ void read_persistent_clock64(struct timespec64 *ts)
if (time_travel_start_set)
nsecs = time_travel_start + time_travel_time;
+ else if (time_travel_mode == TT_MODE_EXTERNAL)
+ nsecs = time_travel_ext_req(UM_TIMETRAVEL_GET_TOD, -1);
else
nsecs = os_persistent_clock_emulation();
@@ -204,7 +688,8 @@ void __init time_init(void)
#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
unsigned long calibrate_delay_is_known(void)
{
- if (time_travel_mode == TT_MODE_INFCPU)
+ if (time_travel_mode == TT_MODE_INFCPU ||
+ time_travel_mode == TT_MODE_EXTERNAL)
return 1;
return 0;
}
@@ -218,6 +703,13 @@ int setup_time_travel(char *str)
return 1;
}
+ if (strncmp(str, "=ext:", 5) == 0) {
+ time_travel_mode = TT_MODE_EXTERNAL;
+ timer_clockevent.name = "time-travel-timer-external";
+ timer_clocksource.name = "time-travel-clock-external";
+ return time_travel_connect_external(str + 5);
+ }
+
if (!*str) {
time_travel_mode = TT_MODE_BASIC;
timer_clockevent.name = "time-travel-timer";
@@ -242,7 +734,15 @@ __uml_help(setup_time_travel,
"are no wall clock timers, and any CPU processing happens - as seen from the\n"
"guest - instantly. This can be useful for accurate simulation regardless of\n"
"debug overhead, physical CPU speed, etc. but is somewhat dangerous as it can\n"
-"easily lead to getting stuck (e.g. if anything in the system busy loops).\n");
+"easily lead to getting stuck (e.g. if anything in the system busy loops).\n"
+"\n"
+"time-travel=ext:[ID:]/path/to/socket\n"
+"This enables time travel mode similar to =inf-cpu, except the system will\n"
+"use the given socket to coordinate with a central scheduler, in order to\n"
+"have more than one system simultaneously be on simulated time. The virtio\n"
+"driver code in UML knows about this so you can also simulate networks and\n"
+"devices using it, assuming the device has the right capabilities.\n"
+"The optional ID is a 64-bit integer that's sent to the central scheduler.\n");
int setup_time_travel_start(char *str)
{
diff --git a/arch/um/kernel/uml.lds.S b/arch/um/kernel/uml.lds.S
index 9f21443be2c9e73f2fe0fbd089fc927760709d7e..3b6dab3d45018a51d463c58efcce85508328f9ce 100644
--- a/arch/um/kernel/uml.lds.S
+++ b/arch/um/kernel/uml.lds.S
@@ -19,10 +19,10 @@ SECTIONS
__binary_start = START;
. = START + SIZEOF_HEADERS;
+ . = ALIGN(PAGE_SIZE);
_text = .;
INIT_TEXT_SECTION(0)
- . = ALIGN(PAGE_SIZE);
.text :
{
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index fbda10535dab052a6ef41181b8844ef63f5adc50..26ecbd64c4094f372d90b3ca1c4f6c2ce60ea544 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -5,9 +5,11 @@
#include <stdio.h>
#include <unistd.h>
+#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
+#include <linux/falloc.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/socket.h>
@@ -16,6 +18,7 @@
#include <sys/un.h>
#include <sys/types.h>
#include <sys/eventfd.h>
+#include <poll.h>
#include <os.h>
static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
@@ -664,3 +667,31 @@ int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds,
return -errno;
return err;
}
+
+int os_poll(unsigned int n, const int *fds)
+{
+ /* currently need 2 FDs at most so avoid dynamic allocation */
+ struct pollfd pollfds[2] = {};
+ unsigned int i;
+ int ret;
+
+ if (n > ARRAY_SIZE(pollfds))
+ return -EINVAL;
+
+ for (i = 0; i < n; i++) {
+ pollfds[i].fd = fds[i];
+ pollfds[i].events = POLLIN;
+ }
+
+ ret = poll(pollfds, n, -1);
+ if (ret < 0)
+ return -errno;
+
+ /* Return the index of the available FD */
+ for (i = 0; i < n; i++) {
+ if (pollfds[i].revents)
+ return i;
+ }
+
+ return -EIO;
+}
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
index 432f8e1f55c2f892ac1a9fe66263aa30638d22e8..90f6de224c700d76402a36b598c199f08b217143 100644
--- a/arch/um/os-Linux/time.c
+++ b/arch/um/os-Linux/time.c
@@ -14,7 +14,6 @@
#include <kern_util.h>
#include <os.h>
#include <string.h>
-#include <timer-internal.h>
static timer_t event_high_res_timer = 0;
diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c
index 44def53a11cd627b00dc5701076b9cb5541ce227..9e16078a4bf8f30067c05532c8e87b67080e0942 100644
--- a/arch/um/os-Linux/umid.c
+++ b/arch/um/os-Linux/umid.c
@@ -220,11 +220,12 @@ static void __init create_pid_file(void)
char pid[sizeof("nnnnn\0")], *file;
int fd, n;
- file = malloc(strlen(uml_dir) + UMID_LEN + sizeof("/pid\0"));
+ n = strlen(uml_dir) + UMID_LEN + sizeof("/pid\0");
+ file = malloc(n);
if (!file)
return;
- if (umid_file_name("pid", file, sizeof(file)))
+ if (umid_file_name("pid", file, n))
goto out;
fd = open(file, O_RDWR | O_CREAT | O_EXCL, 0644);
diff --git a/arch/x86/um/asm/processor.h b/arch/x86/um/asm/processor.h
index 593d5f3902bd60a5eeb2b7f1ebc9decf6276e738..478710384b340fe2ec28133c26dda88ca56fec11 100644
--- a/arch/x86/um/asm/processor.h
+++ b/arch/x86/um/asm/processor.h
@@ -1,6 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __UM_PROCESSOR_H
#define __UM_PROCESSOR_H
+#include <linux/time-internal.h>
/* include faultinfo structure */
#include <sysdep/faultinfo.h>
@@ -21,12 +22,19 @@
#include <asm/user.h>
/* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
-static inline void rep_nop(void)
+static __always_inline void rep_nop(void)
{
__asm__ __volatile__("rep;nop": : :"memory");
}
-#define cpu_relax() rep_nop()
+static __always_inline void cpu_relax(void)
+{
+ if (time_travel_mode == TT_MODE_INFCPU ||
+ time_travel_mode == TT_MODE_EXTERNAL)
+ time_travel_ndelay(1);
+ else
+ rep_nop();
+}
#define task_pt_regs(t) (&(t)->thread.regs)
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index e6b8c49076bbcdbebad6a557c744a6c1546c385d..c070c0d8e3e977b7fbc830bb58ac302abc93f5da 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -139,8 +139,8 @@ static char *inode_name(struct inode *ino)
static char *follow_link(char *link)
{
- int len, n;
char *name, *resolved, *end;
+ int n;
name = __getname();
if (!name) {
@@ -164,15 +164,13 @@ static char *follow_link(char *link)
return name;
*(end + 1) = '\0';
- len = strlen(link) + strlen(name) + 1;
- resolved = kmalloc(len, GFP_KERNEL);
+ resolved = kasprintf(GFP_KERNEL, "%s%s", link, name);
if (resolved == NULL) {
n = -ENOMEM;
goto out_free;
}
- sprintf(resolved, "%s%s", link, name);
__putname(name);
kfree(link);
return resolved;
@@ -921,18 +919,16 @@ static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent)
sb->s_d_op = &simple_dentry_operations;
sb->s_maxbytes = MAX_LFS_FILESIZE;
- /* NULL is printed as <NULL> by sprintf: avoid that. */
+ /* NULL is printed as '(null)' by printf(): avoid that. */
if (req_root == NULL)
req_root = "";
err = -ENOMEM;
sb->s_fs_info = host_root_path =
- kmalloc(strlen(root_ino) + strlen(req_root) + 2, GFP_KERNEL);
+ kasprintf(GFP_KERNEL, "%s/%s", root_ino, req_root);
if (host_root_path == NULL)
goto out;
- sprintf(host_root_path, "%s/%s", root_ino, req_root);
-
root_inode = new_inode(sb);
if (!root_inode)
goto out;
diff --git a/include/uapi/linux/um_timetravel.h b/include/uapi/linux/um_timetravel.h
new file mode 100644
index 0000000000000000000000000000000000000000..ca3238222b6d6062b1461a0db33d26f8f6362cd2
--- /dev/null
+++ b/include/uapi/linux/um_timetravel.h
@@ -0,0 +1,128 @@
+/*
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Copyright (C) 2019 Intel Corporation
+ */
+#ifndef _UAPI_LINUX_UM_TIMETRAVEL_H
+#define _UAPI_LINUX_UM_TIMETRAVEL_H
+#include <linux/types.h>
+
+/**
+ * struct um_timetravel_msg - UM time travel message
+ *
+ * This is the basic message type, going in both directions.
+ *
+ * This is the message passed between the host (user-mode Linux instance)
+ * and the calendar (the application on the other side of the socket) in
+ * order to implement common scheduling.
+ *
+ * Whenever UML has an event it will request runtime for it from the
+ * calendar, and then wait for its turn until it can run, etc. Note
+ * that it will only ever request the single next runtime, i.e. multiple
+ * REQUEST messages override each other.
+ */
+struct um_timetravel_msg {
+ /**
+ * @op: operation value from &enum um_timetravel_ops
+ */
+ __u32 op;
+
+ /**
+ * @seq: sequence number for the message - shall be reflected in
+ * the ACK response, and should be checked while processing
+ * the response to see if it matches
+ */
+ __u32 seq;
+
+ /**
+ * @time: time in nanoseconds
+ */
+ __u64 time;
+};
+
+/**
+ * enum um_timetravel_ops - Operation codes
+ */
+enum um_timetravel_ops {
+ /**
+ * @UM_TIMETRAVEL_ACK: response (ACK) to any previous message,
+ * this usually doesn't carry any data in the 'time' field
+ * unless otherwise specified below
+ */
+ UM_TIMETRAVEL_ACK = 0,
+
+ /**
+ * @UM_TIMETRAVEL_START: initialize the connection, the time
+ * field contains an (arbitrary) ID to possibly be able
+ * to distinguish the connections.
+ */
+ UM_TIMETRAVEL_START = 1,
+
+ /**
+ * @UM_TIMETRAVEL_REQUEST: request to run at the given time
+ * (host -> calendar)
+ */
+ UM_TIMETRAVEL_REQUEST = 2,
+
+ /**
+ * @UM_TIMETRAVEL_WAIT: Indicate waiting for the previously requested
+ * runtime, new requests may be made while waiting (e.g. due to
+ * interrupts); the time field is ignored. The calendar must process
+ * this message and later send a %UM_TIMETRAVEL_RUN message when
+ * the host can run again.
+ * (host -> calendar)
+ */
+ UM_TIMETRAVEL_WAIT = 3,
+
+ /**
+ * @UM_TIMETRAVEL_GET: return the current time from the calendar in the
+ * ACK message, the time in the request message is ignored
+ * (host -> calendar)
+ */
+ UM_TIMETRAVEL_GET = 4,
+
+ /**
+ * @UM_TIMETRAVEL_UPDATE: time update to the calendar, must be sent e.g.
+ * before kicking an interrupt to another calendar
+ * (host -> calendar)
+ */
+ UM_TIMETRAVEL_UPDATE = 5,
+
+ /**
+ * @UM_TIMETRAVEL_RUN: run time request granted, current time is in
+ * the time field
+ * (calendar -> host)
+ */
+ UM_TIMETRAVEL_RUN = 6,
+
+ /**
+ * @UM_TIMETRAVEL_FREE_UNTIL: Enable free-running until the given time,
+ * this is a message from the calendar telling the host that it can
+ * freely do its own scheduling for anything before the indicated
+ * time.
+ * Note that if a calendar sends this message once, the host may
+ * assume that it will also do so in the future, if it implements
+ * wraparound semantics for the time field.
+ * (calendar -> host)
+ */
+ UM_TIMETRAVEL_FREE_UNTIL = 7,
+
+ /**
+ * @UM_TIMETRAVEL_GET_TOD: Return time of day, typically used once at
+ * boot by the virtual machines to get a synchronized time from
+ * the simulation.
+ */
+ UM_TIMETRAVEL_GET_TOD = 8,
+};
+
+#endif /* _UAPI_LINUX_UM_TIMETRAVEL_H */