asmlinkage long sys_setpriority(int which, int who, int niceval)
{
struct task_struct *p;
int error;
if (which > 2 || which < 0)
return -EINVAL;
/* normalize: avoid signed division (rounding problems) */
error = -ESRCH;
if (niceval < -20)
niceval = -20;
if (niceval > 19)
niceval = 19;
read_lock(&tasklist_lock);
for_each_task(p) {
if (!proc_sel(p, which, who))
continue;
if (p->uid != current->euid &&
p->uid != current->uid && !capable(CAP_SYS_NICE)) {
error = -EPERM;
continue;
}
if (error == -ESRCH)
error = 0;
if (niceval < p->nice && !capable(CAP_SYS_NICE))
error = -EACCES;
else
p->nice = niceval;
}
read_unlock(&tasklist_lock);
return error;
}
asmlinkage int sys_setpriority(int which, int who, int niceval)
{
struct task_struct **p;
int error = ESRCH;
int priority;
if (which > 2 || which < 0)
return -EINVAL;
if ((priority = PZERO - niceval) <= 0)
priority = 1;
for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
if (!*p || !proc_sel(*p, which, who))
continue;
if ((*p)->uid != current->euid &&
(*p)->uid != current->uid && !suser()) {
error = EPERM;
continue;
}
if (error == ESRCH)
error = 0;
if (priority > (*p)->priority && !suser())
error = EACCES;
else
(*p)->priority = priority;
}
return -error;
}
asmlinkage int sys_getpriority(int which, int who)
{
struct task_struct **p;
int max_prio = 0;
if (which > 2 || which < 0)
return -EINVAL;
for(p = &LAST_TASK; p > &FIRST_TASK; --p) {
if (!*p || !proc_sel(*p, which, who))
continue;
if ((*p)->priority > max_prio)
max_prio = (*p)->priority;
}
return(max_prio ? max_prio : -ESRCH);
}
/*
* Ugh. To avoid negative return values, "getpriority()" will
* not return the normal nice-value, but a value that has been
* offset by 20 (ie it returns 0..40 instead of -20..20)
*/
asmlinkage int sys_getpriority(int which, int who)
{
struct task_struct *p;
long max_prio = -ESRCH;
if (which > 2 || which < 0)
return -EINVAL;
for_each_task (p) {
if (!proc_sel(p, which, who))
continue;
if (p->priority > max_prio)
max_prio = p->priority;
}
/* scale the priority from timeslice to 0..40 */
if (max_prio > 0)
max_prio = (max_prio * 20 + DEF_PRIORITY/2) / DEF_PRIORITY;
return max_prio;
}
/*
* Ugh. To avoid negative return values, "getpriority()" will
* not return the normal nice-value, but a negated value that
* has been offset by 20 (ie it returns 40..1 instead of -20..19)
* to stay compatible.
*/
asmlinkage long sys_getpriority(int which, int who)
{
struct task_struct *p;
long retval = -ESRCH;
if (which > 2 || which < 0)
return -EINVAL;
read_lock(&tasklist_lock);
for_each_task (p) {
long niceval;
if (!proc_sel(p, which, who))
continue;
niceval = 20 - p->nice;
if (niceval > retval)
retval = niceval;
}
read_unlock(&tasklist_lock);
return retval;
}
asmlinkage int sys_setpriority(int which, int who, int niceval)
{
struct task_struct *p;
int error = ESRCH;
unsigned int priority;
if (which > 2 || which < 0)
return -EINVAL;
/* normalize: avoid signed division (rounding problems) */
priority = niceval;
if (niceval < 0)
priority = -niceval;
if (priority > 20)
priority = 20;
priority = (priority * DEF_PRIORITY + 10) / 20 + DEF_PRIORITY;
if (niceval >= 0) {
priority = 2*DEF_PRIORITY - priority;
if (!priority)
priority = 1;
}
for_each_task(p) {
if (!proc_sel(p, which, who))
continue;
if (p->uid != current->euid &&
p->uid != current->uid && !suser()) {
error = EPERM;
continue;
}
if (error == ESRCH)
error = 0;
if (priority > p->priority && !suser())
error = EACCES;
else
p->priority = priority;
}
return -error;
}
