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authorRusty Russell <rusty@rustcorp.com.au>2009-06-13 08:27:08 +0400
committerRusty Russell <rusty@rustcorp.com.au>2009-06-12 16:57:09 +0400
commit9f155a9b3d5a5444bcc5e049ec2547bb5107150e (patch)
treeef8fe2d5a319abb3bb1c89374f9d2fef1b0881c3 /drivers/lguest
parent92b4d8df8436cdd74d22a2a5b6b23b9abc737a3e (diff)
downloadlinux-9f155a9b3d5a5444bcc5e049ec2547bb5107150e.tar.xz
lguest: allow any process to send interrupts
We currently only allow the Launcher process to send interrupts, but it as we already send interrupts from the hrtimer, it's a simple matter of extracting that code into a common set_interrupt routine. As we switch to a thread per virtqueue, this avoids a bottleneck through the main Launcher process. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/lguest')
-rw-r--r--drivers/lguest/interrupts_and_traps.c19
-rw-r--r--drivers/lguest/lg.h1
-rw-r--r--drivers/lguest/lguest_user.c10
3 files changed, 18 insertions, 12 deletions
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index 5a10754b4790..0e9067b0d507 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -213,6 +213,20 @@ void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more)
if (!more)
put_user(0, &cpu->lg->lguest_data->irq_pending);
}
+
+/* And this is the routine when we want to set an interrupt for the Guest. */
+void set_interrupt(struct lg_cpu *cpu, unsigned int irq)
+{
+ /* Next time the Guest runs, the core code will see if it can deliver
+ * this interrupt. */
+ set_bit(irq, cpu->irqs_pending);
+
+ /* Make sure it sees it; it might be asleep (eg. halted), or
+ * running the Guest right now, in which case kick_process()
+ * will knock it out. */
+ if (!wake_up_process(cpu->tsk))
+ kick_process(cpu->tsk);
+}
/*:*/
/* Linux uses trap 128 for system calls. Plan9 uses 64, and Ron Minnich sent
@@ -528,10 +542,7 @@ static enum hrtimer_restart clockdev_fn(struct hrtimer *timer)
struct lg_cpu *cpu = container_of(timer, struct lg_cpu, hrt);
/* Remember the first interrupt is the timer interrupt. */
- set_bit(0, cpu->irqs_pending);
- /* Guest may be stopped or running on another CPU. */
- if (!wake_up_process(cpu->tsk))
- kick_process(cpu->tsk);
+ set_interrupt(cpu, 0);
return HRTIMER_NORESTART;
}
diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 6201ce59e886..040cb70780e7 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -143,6 +143,7 @@ int run_guest(struct lg_cpu *cpu, unsigned long __user *user);
/* interrupts_and_traps.c: */
unsigned int interrupt_pending(struct lg_cpu *cpu, bool *more);
void try_deliver_interrupt(struct lg_cpu *cpu, unsigned int irq, bool more);
+void set_interrupt(struct lg_cpu *cpu, unsigned int irq);
bool deliver_trap(struct lg_cpu *cpu, unsigned int num);
void load_guest_idt_entry(struct lg_cpu *cpu, unsigned int i,
u32 low, u32 hi);
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index bcdcf3453e78..1982b45bd935 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -45,9 +45,8 @@ static int user_send_irq(struct lg_cpu *cpu, const unsigned long __user *input)
return -EFAULT;
if (irq >= LGUEST_IRQS)
return -EINVAL;
- /* Next time the Guest runs, the core code will see if it can deliver
- * this interrupt. */
- set_bit(irq, cpu->irqs_pending);
+
+ set_interrupt(cpu, irq);
return 0;
}
@@ -252,11 +251,6 @@ static ssize_t write(struct file *file, const char __user *in,
/* Once the Guest is dead, you can only read() why it died. */
if (lg->dead)
return -ENOENT;
-
- /* If you're not the task which owns the Guest, all you can do
- * is break the Launcher out of running the Guest. */
- if (current != cpu->tsk && req != LHREQ_BREAK)
- return -EPERM;
}
switch (req) {