static const char *
sprint_ioprio(int ioprio)
{
static char outstr[256];
const char *str;
int class, data;
class = IOPRIO_PRIO_CLASS(ioprio);
data = IOPRIO_PRIO_DATA(ioprio);
str = xlookup(ioprio_class, class);
if (str)
sprintf(outstr, "IOPRIO_PRIO_VALUE(%s,%d)", str, data);
else
sprintf(outstr, "IOPRIO_PRIO_VALUE(%#x /* %s */,%d)",
class, "IOPRIO_CLASS_???", data);
return outstr;
}
static void ioprio_print(int pid)
{
int ioprio = ioprio_get(IOPRIO_WHO_PROCESS, pid);
if (ioprio == -1)
err(EXIT_FAILURE, _("ioprio_get failed"));
else {
int ioclass = IOPRIO_PRIO_CLASS(ioprio);
const char *name = _("unknown");
if (ioclass > 0 && (size_t) ioclass < ARRAY_SIZE(to_prio))
name = to_prio[ioclass];
if (ioclass != IOPRIO_CLASS_IDLE)
printf(_("%s: prio %lu\n"), name,
IOPRIO_PRIO_DATA(ioprio));
else
printf("%s\n", name);
}
}
SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio)
{
int class = IOPRIO_PRIO_CLASS(ioprio);
int data = IOPRIO_PRIO_DATA(ioprio);
struct task_struct *p, *g;
struct user_struct *user;
struct pid *pgrp;
int ret;
switch (class) {
case IOPRIO_CLASS_RT:
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
/* fall through, rt has prio field too */
case IOPRIO_CLASS_BE:
if (data >= IOPRIO_BE_NR || data < 0)
return -EINVAL;
break;
case IOPRIO_CLASS_IDLE:
break;
case IOPRIO_CLASS_NONE:
if (data)
return -EINVAL;
break;
default:
return -EINVAL;
}
ret = -ESRCH;
rcu_read_lock();
switch (which) {
case IOPRIO_WHO_PROCESS:
if (!who)
p = current;
else
p = find_task_by_vpid(who);
if (p)
ret = set_task_ioprio(p, ioprio);
break;
case IOPRIO_WHO_PGRP:
if (!who)
pgrp = task_pgrp(current);
else
pgrp = find_vpid(who);
do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
ret = set_task_ioprio(p, ioprio);
if (ret)
break;
} while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
break;
case IOPRIO_WHO_USER:
if (!who)
user = current_user();
else
user = find_user(who);
if (!user)
break;
do_each_thread(g, p) {
if (__task_cred(p)->uid != who)
continue;
ret = set_task_ioprio(p, ioprio);
if (ret)
goto free_uid;
} while_each_thread(g, p);
free_uid:
if (who)
free_uid(user);
break;
default:
ret = -EINVAL;
}