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-rw-r--r--drivers/char/hw_random/core.c28
-rw-r--r--drivers/char/hw_random/virtio-rng.c13
-rw-r--r--drivers/char/random.c12
-rw-r--r--drivers/char/virtio_console.c44
4 files changed, 74 insertions, 23 deletions
diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c
index 1bafb40ec8a..a0f7724852e 100644
--- a/drivers/char/hw_random/core.c
+++ b/drivers/char/hw_random/core.c
@@ -40,6 +40,7 @@
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/delay.h>
+#include <linux/slab.h>
#include <asm/uaccess.h>
@@ -52,8 +53,12 @@ static struct hwrng *current_rng;
static LIST_HEAD(rng_list);
static DEFINE_MUTEX(rng_mutex);
static int data_avail;
-static u8 rng_buffer[SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES]
- __cacheline_aligned;
+static u8 *rng_buffer;
+
+static size_t rng_buffer_size(void)
+{
+ return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES;
+}
static inline int hwrng_init(struct hwrng *rng)
{
@@ -116,7 +121,7 @@ static ssize_t rng_dev_read(struct file *filp, char __user *buf,
if (!data_avail) {
bytes_read = rng_get_data(current_rng, rng_buffer,
- sizeof(rng_buffer),
+ rng_buffer_size(),
!(filp->f_flags & O_NONBLOCK));
if (bytes_read < 0) {
err = bytes_read;
@@ -307,6 +312,14 @@ int hwrng_register(struct hwrng *rng)
mutex_lock(&rng_mutex);
+ /* kmalloc makes this safe for virt_to_page() in virtio_rng.c */
+ err = -ENOMEM;
+ if (!rng_buffer) {
+ rng_buffer = kmalloc(rng_buffer_size(), GFP_KERNEL);
+ if (!rng_buffer)
+ goto out_unlock;
+ }
+
/* Must not register two RNGs with the same name. */
err = -EEXIST;
list_for_each_entry(tmp, &rng_list, list) {
@@ -367,6 +380,15 @@ void hwrng_unregister(struct hwrng *rng)
}
EXPORT_SYMBOL_GPL(hwrng_unregister);
+static void __exit hwrng_exit(void)
+{
+ mutex_lock(&rng_mutex);
+ BUG_ON(current_rng);
+ kfree(rng_buffer);
+ mutex_unlock(&rng_mutex);
+}
+
+module_exit(hwrng_exit);
MODULE_DESCRIPTION("H/W Random Number Generator (RNG) driver");
MODULE_LICENSE("GPL");
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index 10fd71ccf58..6bf4d47324e 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -92,14 +92,22 @@ static int probe_common(struct virtio_device *vdev)
{
int err;
+ if (vq) {
+ /* We only support one device for now */
+ return -EBUSY;
+ }
/* We expect a single virtqueue. */
vq = virtio_find_single_vq(vdev, random_recv_done, "input");
- if (IS_ERR(vq))
- return PTR_ERR(vq);
+ if (IS_ERR(vq)) {
+ err = PTR_ERR(vq);
+ vq = NULL;
+ return err;
+ }
err = hwrng_register(&virtio_hwrng);
if (err) {
vdev->config->del_vqs(vdev);
+ vq = NULL;
return err;
}
@@ -112,6 +120,7 @@ static void remove_common(struct virtio_device *vdev)
busy = false;
hwrng_unregister(&virtio_hwrng);
vdev->config->del_vqs(vdev);
+ vq = NULL;
}
static int virtrng_probe(struct virtio_device *vdev)
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 594bda9dcfc..32a6c576495 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -852,6 +852,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min,
int reserved)
{
unsigned long flags;
+ int wakeup_write = 0;
/* Hold lock while accounting */
spin_lock_irqsave(&r->lock, flags);
@@ -873,10 +874,8 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min,
else
r->entropy_count = reserved;
- if (r->entropy_count < random_write_wakeup_thresh) {
- wake_up_interruptible(&random_write_wait);
- kill_fasync(&fasync, SIGIO, POLL_OUT);
- }
+ if (r->entropy_count < random_write_wakeup_thresh)
+ wakeup_write = 1;
}
DEBUG_ENT("debiting %zu entropy credits from %s%s\n",
@@ -884,6 +883,11 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min,
spin_unlock_irqrestore(&r->lock, flags);
+ if (wakeup_write) {
+ wake_up_interruptible(&random_write_wait);
+ kill_fasync(&fasync, SIGIO, POLL_OUT);
+ }
+
return nbytes;
}
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e905d5f5305..ce5f3fc25d6 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -149,7 +149,8 @@ struct ports_device {
spinlock_t ports_lock;
/* To protect the vq operations for the control channel */
- spinlock_t cvq_lock;
+ spinlock_t c_ivq_lock;
+ spinlock_t c_ovq_lock;
/* The current config space is stored here */
struct virtio_console_config config;
@@ -569,11 +570,14 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
vq = portdev->c_ovq;
sg_init_one(sg, &cpkt, sizeof(cpkt));
+
+ spin_lock(&portdev->c_ovq_lock);
if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) == 0) {
virtqueue_kick(vq);
while (!virtqueue_get_buf(vq, &len))
cpu_relax();
}
+ spin_unlock(&portdev->c_ovq_lock);
return 0;
}
@@ -1436,7 +1440,7 @@ static int add_port(struct ports_device *portdev, u32 id)
* rproc_serial does not want the console port, only
* the generic port implementation.
*/
- port->host_connected = port->guest_connected = true;
+ port->host_connected = true;
else if (!use_multiport(port->portdev)) {
/*
* If we're not using multiport support,
@@ -1709,23 +1713,23 @@ static void control_work_handler(struct work_struct *work)
portdev = container_of(work, struct ports_device, control_work);
vq = portdev->c_ivq;
- spin_lock(&portdev->cvq_lock);
+ spin_lock(&portdev->c_ivq_lock);
while ((buf = virtqueue_get_buf(vq, &len))) {
- spin_unlock(&portdev->cvq_lock);
+ spin_unlock(&portdev->c_ivq_lock);
buf->len = len;
buf->offset = 0;
handle_control_message(portdev, buf);
- spin_lock(&portdev->cvq_lock);
+ spin_lock(&portdev->c_ivq_lock);
if (add_inbuf(portdev->c_ivq, buf) < 0) {
dev_warn(&portdev->vdev->dev,
"Error adding buffer to queue\n");
free_buf(buf, false);
}
}
- spin_unlock(&portdev->cvq_lock);
+ spin_unlock(&portdev->c_ivq_lock);
}
static void out_intr(struct virtqueue *vq)
@@ -1752,13 +1756,23 @@ static void in_intr(struct virtqueue *vq)
port->inbuf = get_inbuf(port);
/*
- * Don't queue up data when port is closed. This condition
+ * Normally the port should not accept data when the port is
+ * closed. For generic serial ports, the host won't (shouldn't)
+ * send data till the guest is connected. But this condition
* can be reached when a console port is not yet connected (no
- * tty is spawned) and the host sends out data to console
- * ports. For generic serial ports, the host won't
- * (shouldn't) send data till the guest is connected.
+ * tty is spawned) and the other side sends out data over the
+ * vring, or when a remote devices start sending data before
+ * the ports are opened.
+ *
+ * A generic serial port will discard data if not connected,
+ * while console ports and rproc-serial ports accepts data at
+ * any time. rproc-serial is initiated with guest_connected to
+ * false because port_fops_open expects this. Console ports are
+ * hooked up with an HVC console and is initialized with
+ * guest_connected to true.
*/
- if (!port->guest_connected)
+
+ if (!port->guest_connected && !is_rproc_serial(port->portdev->vdev))
discard_port_data(port);
spin_unlock_irqrestore(&port->inbuf_lock, flags);
@@ -1986,10 +2000,12 @@ static int virtcons_probe(struct virtio_device *vdev)
if (multiport) {
unsigned int nr_added_bufs;
- spin_lock_init(&portdev->cvq_lock);
+ spin_lock_init(&portdev->c_ivq_lock);
+ spin_lock_init(&portdev->c_ovq_lock);
INIT_WORK(&portdev->control_work, &control_work_handler);
- nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+ nr_added_bufs = fill_queue(portdev->c_ivq,
+ &portdev->c_ivq_lock);
if (!nr_added_bufs) {
dev_err(&vdev->dev,
"Error allocating buffers for control queue\n");
@@ -2140,7 +2156,7 @@ static int virtcons_restore(struct virtio_device *vdev)
return ret;
if (use_multiport(portdev))
- fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+ fill_queue(portdev->c_ivq, &portdev->c_ivq_lock);
list_for_each_entry(port, &portdev->ports, list) {
port->in_vq = portdev->in_vqs[port->id];
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 03:48:07 +0000