[PATCH 08/16] per-vcpu interrupt processing.

Glauber de Oliveira Costa
2008-01-07T13:08:50Z

This patch adapts interrupt processing for using the vcpu struct.

Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
---
drivers/lguest/core.c | 2 +-
drivers/lguest/interrupts_and_traps.c | 25 ++++++++++++++-----------
drivers/lguest/lg.h | 10 +++++-----
drivers/lguest/lguest_user.c | 7 ++++---
drivers/lguest/x86/core.c | 2 +-
5 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/drivers/lguest/core.c b/drivers/lguest/core.c
index 99f65f9..bc3b32d 100644
--- a/drivers/lguest/core.c
+++ b/drivers/lguest/core.c
@@ -203,7 +203,7 @@ int run_guest(struct lg_vcpu *vcpu, unsigned long __user *user)
/* Check if there are any interrupts which can be delivered
* now: if so, this sets up the hander to be executed when we
* next run the Guest. */
- maybe_do_interrupt(lg);
+ maybe_do_interrupt(vcpu);

/* All long-lived kernel loops need to check with this horrible
* thing called the freezer. If the Host is trying to suspend,
diff --git a/drivers/lguest/interrupts_and_traps.c b/drivers/lguest/interrupts_and_traps.c
index 3be18a6..d28671b 100644
--- a/drivers/lguest/interrupts_and_traps.c
+++ b/drivers/lguest/interrupts_and_traps.c
@@ -60,11 +60,13 @@ static void push_guest_stack(struct lguest *lg, unsigned long *gstack, u32 val)
* We set up the stack just like the CPU does for a real interrupt, so it's
* identical for the Guest (and the standard "iret" instruction will undo
* it). */
-static void set_guest_interrupt(struct lguest *lg, u32 lo, u32 hi, int has_err)
+static void set_guest_interrupt(struct lg_vcpu *vcpu, u32 lo, u32 hi,
+ int has_err)
{
unsigned long gstack, origstack;
u32 eflags, ss, irq_enable;
unsigned long virtstack;
+ struct lguest *lg = vcpu->lg;

/* There are two cases for interrupts: one where the Guest is already
* in the kernel, and a more complex one where the Guest is in
@@ -129,9 +131,10 @@ static void set_guest_interrupt(struct lguest *lg, u32 lo, u32 hi, int has_err)
*
* maybe_do_interrupt() gets called before every entry to the Guest, to see if
* we should divert the Guest to running an interrupt handler. */
-void maybe_do_interrupt(struct lguest *lg)
+void maybe_do_interrupt(struct lg_vcpu *vcpu)
{
unsigned int irq;
+ struct lguest *lg = vcpu->lg;
DECLARE_BITMAP(blk, LGUEST_IRQS);
struct desc_struct *idt;

@@ -145,7 +148,7 @@ void maybe_do_interrupt(struct lguest *lg)
sizeof(blk)))
return;

- bitmap_andnot(blk, lg->irqs_pending, blk, LGUEST_IRQS);
+ bitmap_andnot(blk, vcpu->irqs_pending, blk, LGUEST_IRQS);

/* Find the first interrupt. */
irq = find_first_bit(blk, LGUEST_IRQS);
@@ -180,11 +183,11 @@ void maybe_do_interrupt(struct lguest *lg)
/* If they don't have a handler (yet?), we just ignore it */
if (idt_present(idt->a, idt->b)) {
/* OK, mark it no longer pending and deliver it. */
- clear_bit(irq, lg->irqs_pending);
+ clear_bit(irq, vcpu->irqs_pending);
/* set_guest_interrupt() takes the interrupt descriptor and a
* flag to say whether this interrupt pushes an error code onto
* the stack as well: virtual interrupts never do. */
- set_guest_interrupt(lg, idt->a, idt->b, 0);
+ set_guest_interrupt(vcpu, idt->a, idt->b, 0);
}

/* Every time we deliver an interrupt, we update the timestamp in the
@@ -245,19 +248,19 @@ static int has_err(unsigned int trap)
}

/* deliver_trap() returns true if it could deliver the trap. */
-int deliver_trap(struct lguest *lg, unsigned int num)
+int deliver_trap(struct lg_vcpu *vcpu, unsigned int num)
{
/* Trap numbers are always 8 bit, but we set an impossible trap number
* for traps inside the Switcher, so check that here. */
- if (num >= ARRAY_SIZE(lg->arch.idt))
+ if (num >= ARRAY_SIZE(vcpu->lg->arch.idt))
return 0;

/* Early on the Guest hasn't set the IDT entries (or maybe it put a
* bogus one in): if we fail here, the Guest will be killed. */
- if (!idt_present(lg->arch.idt[num].a, lg->arch.idt[num].b))
+ if (!idt_present(vcpu->lg->arch.idt[num].a, vcpu->lg->arch.idt[num].b))
return 0;
- set_guest_interrupt(lg, lg->arch.idt[num].a, lg->arch.idt[num].b,
- has_err(num));
+ set_guest_interrupt(vcpu, vcpu->lg->arch.idt[num].a,
+ vcpu->lg->arch.idt[num].b, has_err(num));
return 1;
}

@@ -493,7 +496,7 @@ static enum hrtimer_restart clockdev_fn(struct hrtimer *timer)
struct lg_vcpu *vcpu = container_of(timer, struct lg_vcpu, hrt);

/* Remember the first interrupt is the timer interrupt. */
- set_bit(0, vcpu->lg->irqs_pending);
+ set_bit(0, vcpu->irqs_pending);
/* If the Guest is actually stopped, we need to wake it up. */
if (vcpu->lg->halted)
wake_up_process(vcpu->lg->tsk);
diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 9c90fd3..6c794cd 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -50,6 +50,9 @@ struct lg_vcpu {

/* Virtual clock device */
struct hrtimer hrt;
+
+ /* Pending virtual interrupts */
+ DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
};

/* The private info the thread maintains about the guest. */
@@ -97,9 +100,6 @@ struct lguest
const char *dead;

struct lguest_arch arch;
-
- /* Pending virtual interrupts */
- DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);
};

extern struct mutex lguest_lock;
@@ -136,8 +136,8 @@ int run_guest(struct lg_vcpu *vcpu, unsigned long __user *user);
#define pgd_pfn(x) (pgd_val(x) >> PAGE_SHIFT)

/* interrupts_and_traps.c: */
-void maybe_do_interrupt(struct lguest *lg);
-int deliver_trap(struct lguest *lg, unsigned int num);
+void maybe_do_interrupt(struct lg_vcpu *vcpu);
+int deliver_trap(struct lg_vcpu *vcpu, unsigned int num);
void load_guest_idt_entry(struct lguest *lg, unsigned int i, u32 low, u32 hi);
void guest_set_stack(struct lguest *lg, u32 seg, u32 esp, unsigned int pages);
void pin_stack_pages(struct lguest *lg);
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c
index cd2b0bf..abae008 100644
--- a/drivers/lguest/lguest_user.c
+++ b/drivers/lguest/lguest_user.c
@@ -36,7 +36,8 @@ static int break_guest_out(struct lguest *lg, const unsigned long __user *input)

/*L:050 Sending an interrupt is done by writing LHREQ_IRQ and an interrupt
* number to /dev/lguest. */
-static int user_send_irq(struct lguest *lg, const unsigned long __user *input)
+static int user_send_irq(struct lg_vcpu *vcpu,
+ const unsigned long __user *input)
{
unsigned long irq;

@@ -46,7 +47,7 @@ static int user_send_irq(struct lguest *lg, const unsigned long __user *input)
return -EINVAL;
/* Next time the Guest runs, the core code will see if it can deliver
* this interrupt. */
- set_bit(irq, lg->irqs_pending);
+ set_bit(irq, vcpu->irqs_pending);
return 0;
}

@@ -258,7 +259,7 @@ static ssize_t write(struct file *file, const char __user *in,
case LHREQ_INITIALIZE:
return initialize(file, input);
case LHREQ_IRQ:
- return user_send_irq(lg, input);
+ return user_send_irq(vcpu, input);
case LHREQ_BREAK:
return break_guest_out(lg, input);
default:
diff --git a/drivers/lguest/x86/core.c b/drivers/lguest/x86/core.c
index 6877de2..8fbb373 100644
--- a/drivers/lguest/x86/core.c
+++ b/drivers/lguest/x86/core.c
@@ -344,7 +344,7 @@ void lguest_arch_handle_trap(struct lg_vcpu *vcpu)
}

/* We didn't handle the trap, so it needs to go to the Guest. */
- if (!deliver_trap(lg, lg->regs->trapnum))
+ if (!deliver_trap(vcpu, lg->regs->trapnum))
/* If the Guest doesn't have a handler (either it hasn't
* registered any yet, or it's one of the faults we don't let
* it handle), it dies with a cryptic error message. */
--
1.5.0.6