diff options
Diffstat (limited to 'drivers/lguest/lguest_user.c')
| -rw-r--r-- | drivers/lguest/lguest_user.c | 53 |
1 files changed, 28 insertions, 25 deletions
diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c index d21d95b..980b355 100644 --- a/drivers/lguest/lguest_user.c +++ b/drivers/lguest/lguest_user.c @@ -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 __user*input) { 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)) |
