diff options
| -rw-r--r-- | fs/ioprio.c | 31 |
1 files changed, 6 insertions, 25 deletions
diff --git a/fs/ioprio.c b/fs/ioprio.c index 2f7d05c8992..7da2a06508e 100644 --- a/fs/ioprio.c +++ b/fs/ioprio.c @@ -103,22 +103,15 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) } ret = -ESRCH; - /* - * We want IOPRIO_WHO_PGRP/IOPRIO_WHO_USER to be "atomic", - * so we can't use rcu_read_lock(). See re-copy of ->ioprio - * in copy_process(). - */ - read_lock(&tasklist_lock); + rcu_read_lock(); switch (which) { case IOPRIO_WHO_PROCESS: - rcu_read_lock(); if (!who) p = current; else p = find_task_by_vpid(who); if (p) ret = set_task_ioprio(p, ioprio); - rcu_read_unlock(); break; case IOPRIO_WHO_PGRP: if (!who) @@ -141,12 +134,7 @@ SYSCALL_DEFINE3(ioprio_set, int, which, int, who, int, ioprio) break; do_each_thread(g, p) { - int match; - - rcu_read_lock(); - match = __task_cred(p)->uid == who; - rcu_read_unlock(); - if (!match) + if (__task_cred(p)->uid != who) continue; ret = set_task_ioprio(p, ioprio); if (ret) @@ -160,7 +148,7 @@ free_uid: ret = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_unlock(); return ret; } @@ -204,17 +192,15 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who) int ret = -ESRCH; int tmpio; - read_lock(&tasklist_lock); + rcu_read_lock(); switch (which) { case IOPRIO_WHO_PROCESS: - rcu_read_lock(); if (!who) p = current; else p = find_task_by_vpid(who); if (p) ret = get_task_ioprio(p); - rcu_read_unlock(); break; case IOPRIO_WHO_PGRP: if (!who) @@ -241,12 +227,7 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who) break; do_each_thread(g, p) { - int match; - - rcu_read_lock(); - match = __task_cred(p)->uid == user->uid; - rcu_read_unlock(); - if (!match) + if (__task_cred(p)->uid != user->uid) continue; tmpio = get_task_ioprio(p); if (tmpio < 0) @@ -264,6 +245,6 @@ SYSCALL_DEFINE2(ioprio_get, int, which, int, who) ret = -EINVAL; } - read_unlock(&tasklist_lock); + rcu_read_unlock(); return ret; } |