diff options
Diffstat (limited to 'fs/ioprio.c')
-rw-r--r-- | fs/ioprio.c | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/fs/ioprio.c b/fs/ioprio.c index 93aa5715f224..78b1deae3fa2 100644 --- a/fs/ioprio.c +++ b/fs/ioprio.c @@ -44,6 +44,9 @@ static int set_task_ioprio(struct task_struct *task, int ioprio) task->ioprio = ioprio; ioc = task->io_context; + /* see wmb() in current_io_context() */ + smp_read_barrier_depends(); + if (ioc && ioc->set_ioprio) ioc->set_ioprio(ioc, ioprio); @@ -111,9 +114,9 @@ asmlinkage long sys_ioprio_set(int which, int who, int ioprio) continue; ret = set_task_ioprio(p, ioprio); if (ret) - break; + goto free_uid; } while_each_thread(g, p); - +free_uid: if (who) free_uid(user); break; @@ -137,6 +140,29 @@ out: return ret; } +int ioprio_best(unsigned short aprio, unsigned short bprio) +{ + unsigned short aclass = IOPRIO_PRIO_CLASS(aprio); + unsigned short bclass = IOPRIO_PRIO_CLASS(bprio); + + if (!ioprio_valid(aprio)) + return bprio; + if (!ioprio_valid(bprio)) + return aprio; + + if (aclass == IOPRIO_CLASS_NONE) + aclass = IOPRIO_CLASS_BE; + if (bclass == IOPRIO_CLASS_NONE) + bclass = IOPRIO_CLASS_BE; + + if (aclass == bclass) + return min(aprio, bprio); + if (aclass > bclass) + return bprio; + else + return aprio; +} + asmlinkage long sys_ioprio_get(int which, int who) { struct task_struct *g, *p; |