From: Glauber de Oliveira Costa Date: Mon, 7 Jan 2008 13:05:26 +0000 (-0200) Subject: lguest: make write() operation smp aware X-Git-Tag: v2.6.25-rc1~1135^2~19 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7ea07a1500f05e06ebf0136763c781244f77a2a1;p=linux-2.6 lguest: make write() operation smp aware This patch makes the write() file operation smp aware. Which means, receiving the vcpu_id value through the offset parameter, and being well aware to which vcpu we're talking to. Signed-off-by: Glauber de Oliveira Costa Signed-off-by: Rusty Russell --- diff --git a/drivers/lguest/lguest_user.c b/drivers/lguest/lguest_user.c index 9f0a443299..2562082a3e 100644 --- a/drivers/lguest/lguest_user.c +++ b/drivers/lguest/lguest_user.c @@ -227,14 +227,21 @@ static ssize_t write(struct file *file, const char __user *in, struct lguest *lg = file->private_data; const unsigned long __user *input = (const unsigned long __user *)in; unsigned long req; + struct lg_cpu *cpu; + unsigned int cpu_id = *off; if (get_user(req, input) != 0) return -EFAULT; input++; /* If you haven't initialized, you must do that first. */ - if (req != LHREQ_INITIALIZE && !lg) - return -EINVAL; + if (req != LHREQ_INITIALIZE) { + if (!lg || (cpu_id >= lg->nr_cpus)) + return -EINVAL; + cpu = &lg->cpus[cpu_id]; + if (!cpu) + return -EINVAL; + } /* Once the Guest is dead, all you can do is read() why it died. */ if (lg && lg->dead)