lguest: per-vcpu lguest task management (66686c2a) · Commits · 戴 / test

drivers/lguest/core.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -197,7 +197,7 @@ int run_guest(struct lg_cpu cpu, unsigned long __user user)
		return -ERESTARTSYS;

		/* If Waker set break_out, return to Launcher. */
		if (lg->break_out)
		if (cpu->break_out)
		return -EAGAIN;

		/* Check if there are any interrupts which can be delivered
		@@ -217,7 +217,7 @@ int run_guest(struct lg_cpu cpu, unsigned long __user user)

		/* If the Guest asked to be stopped, we sleep. The Guest's
		* clock timer or LHCALL_BREAK from the Waker will wake us. */
		if (lg->halted) {
		if (cpu->halted) {
		set_current_state(TASK_INTERRUPTIBLE);
		schedule();
		continue;

drivers/lguest/hypercalls.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -88,7 +88,7 @@ static void do_hcall(struct lg_cpu cpu, struct hcall_args args)
		break;
		case LHCALL_HALT:
		/* Similarly, this sets the halted flag for run_guest(). */
		lg->halted = 1;
		cpu->halted = 1;
		break;
		case LHCALL_NOTIFY:
		lg->pending_notify = args->arg1;

drivers/lguest/interrupts_and_traps.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -161,11 +161,11 @@ void maybe_do_interrupt(struct lg_cpu *cpu)
		return;

		/* If they're halted, interrupts restart them. */
		if (lg->halted) {
		if (cpu->halted) {
		/* Re-enable interrupts. */
		if (put_user(X86_EFLAGS_IF, &lg->lguest_data->irq_enabled))
		kill_guest(lg, "Re-enabling interrupts");
		lg->halted = 0;
		cpu->halted = 0;
		} else {
		/* Otherwise we check if they have interrupts disabled. */
		u32 irq_enabled;
		@@ -497,8 +497,8 @@ static enum hrtimer_restart clockdev_fn(struct hrtimer *timer)
		/* Remember the first interrupt is the timer interrupt. */
		set_bit(0, cpu->irqs_pending);
		/* If the Guest is actually stopped, we need to wake it up. */
		if (cpu->lg->halted)
		wake_up_process(cpu->lg->tsk);
		if (cpu->halted)
		wake_up_process(cpu->tsk);
		return HRTIMER_NORESTART;
		}

drivers/lguest/lg.h

+7 −7

Original line number	Diff line number	Diff line
		@@ -43,6 +43,8 @@ struct lguest;
		struct lg_cpu {
		unsigned int id;
		struct lguest *lg;
		struct task_struct *tsk;
		struct mm_struct mm; / == tsk->mm, but that becomes NULL on exit */

		/* At end of a page shared mapped over lguest_pages in guest. */
		unsigned long regs_page;
		@@ -55,6 +57,11 @@ struct lg_cpu {
		/* Virtual clock device */
		struct hrtimer hrt;

		/* Do we need to stop what we're doing and return to userspace? */
		int break_out;
		wait_queue_head_t break_wq;
		int halted;

		/* Pending virtual interrupts */
		DECLARE_BITMAP(irqs_pending, LGUEST_IRQS);

		@@ -65,8 +72,6 @@ struct lg_cpu {
		struct lguest
		{
		struct lguest_data __user *lguest_data;
		struct task_struct *tsk;
		struct mm_struct mm; / == tsk->mm, but that becomes NULL on exit */
		struct lg_cpu cpus[NR_CPUS];
		unsigned int nr_cpus;

		@@ -76,15 +81,10 @@ struct lguest
		void __user *mem_base;
		unsigned long kernel_address;
		u32 cr2;
		int halted;
		int ts;
		u32 esp1;
		u8 ss1;

		/* Do we need to stop what we're doing and return to userspace? */
		int break_out;
		wait_queue_head_t break_wq;

		/* Bitmap of what has changed: see CHANGED_* above. */
		int changed;
		struct lguest_pages *last_pages;

drivers/lguest/lguest_user.c

+28 −25

Original line number	Diff line number	Diff line
		@@ -13,7 +13,7 @@
		* LHREQ_BREAK and the value "1" to /dev/lguest to do this. Once the Launcher
		* has done whatever needs attention, it writes LHREQ_BREAK and "0" to release
		* the Waker. */
		static int break_guest_out(struct lguest lg, const unsigned long __user input)
		static int break_guest_out(struct lg_cpu cpu, const unsigned long __userinput)
		{
		unsigned long on;

		@@ -22,14 +22,14 @@ static int break_guest_out(struct lguest lg, const unsigned long __user input)
		return -EFAULT;

		if (on) {
		lg->break_out = 1;
		cpu->break_out = 1;
		/* Pop it out of the Guest (may be running on different CPU) */
		wake_up_process(lg->tsk);
		wake_up_process(cpu->tsk);
		/* Wait for them to reset it */
		return wait_event_interruptible(lg->break_wq, !lg->break_out);
		return wait_event_interruptible(cpu->break_wq, !cpu->break_out);
		} else {
		lg->break_out = 0;
		wake_up(&lg->break_wq);
		cpu->break_out = 0;
		wake_up(&cpu->break_wq);
		return 0;
		}
		}
		@@ -69,7 +69,7 @@ static ssize_t read(struct file file, char __user user, size_t size,loff_t*o)
		cpu = &lg->cpus[cpu_id];

		/* If you're not the task which owns the Guest, go away. */
		if (current != lg->tsk)
		if (current != cpu->tsk)
		return -EPERM;

		/* If the guest is already dead, we indicate why */
		@@ -119,6 +119,18 @@ static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
		* address. */
		lguest_arch_setup_regs(cpu, start_ip);

		/* Initialize the queue for the waker to wait on */
		init_waitqueue_head(&cpu->break_wq);

		/* We keep a pointer to the Launcher task (ie. current task) for when
		* other Guests want to wake this one (inter-Guest I/O). */
		cpu->tsk = current;

		/* We need to keep a pointer to the Launcher's memory map, because if
		* the Launcher dies we need to clean it up. If we don't keep a
		* reference, it is destroyed before close() is called. */
		cpu->mm = get_task_mm(cpu->tsk);

		return 0;
		}

		@@ -180,17 +192,6 @@ static int initialize(struct file file, const unsigned long __user input)
		if (err)
		goto free_regs;

		/* We keep a pointer to the Launcher task (ie. current task) for when
		* other Guests want to wake this one (inter-Guest I/O). */
		lg->tsk = current;
		/* We need to keep a pointer to the Launcher's memory map, because if
		* the Launcher dies we need to clean it up. If we don't keep a
		* reference, it is destroyed before close() is called. */
		lg->mm = get_task_mm(lg->tsk);

		/* Initialize the queue for the waker to wait on */
		init_waitqueue_head(&lg->break_wq);

		/* We remember which CPU's pages this Guest used last, for optimization
		* when the same Guest runs on the same CPU twice. */
		lg->last_pages = NULL;
		@@ -246,7 +247,7 @@ static ssize_t write(struct file file, const char __user in,
		return -ENOENT;

		/* If you're not the task which owns the Guest, you can only break */
		if (lg && current != lg->tsk && req != LHREQ_BREAK)
		if (lg && current != cpu->tsk && req != LHREQ_BREAK)
		return -EPERM;

		switch (req) {
		@@ -255,7 +256,7 @@ static ssize_t write(struct file file, const char __user in,
		case LHREQ_IRQ:
		return user_send_irq(cpu, input);
		case LHREQ_BREAK:
		return break_guest_out(lg, input);
		return break_guest_out(cpu, input);
		default:
		return -EINVAL;
		}
		@@ -280,17 +281,19 @@ static int close(struct inode inode, struct file file)
		/* We need the big lock, to protect from inter-guest I/O and other
		* Launchers initializing guests. */
		mutex_lock(&lguest_lock);

		/* Free up the shadow page tables for the Guest. */
		free_guest_pagetable(lg);

		for (i = 0; i < lg->nr_cpus; i++) {
		/* Cancels the hrtimer set via LHCALL_SET_CLOCKEVENT. */
		hrtimer_cancel(&lg->cpus[i].hrt);
		/* We can free up the register page we allocated. */
		free_page(lg->cpus[i].regs_page);
		/* Now all the memory cleanups are done, it's safe to release
		* the Launcher's memory management structure. */
		mmput(lg->cpus[i].mm);
		}
		/* Free up the shadow page tables for the Guest. */
		free_guest_pagetable(lg);
		/* Now all the memory cleanups are done, it's safe to release the
		* Launcher's memory management structure. */
		mmput(lg->mm);
		/* If lg->dead doesn't contain an error code it will be NULL or a
		* kmalloc()ed string, either of which is ok to hand to kfree(). */
		if (!IS_ERR(lg->dead))

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