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-rw-r--r--fs/ioprio.c241
1 files changed, 0 insertions, 241 deletions
diff --git a/fs/ioprio.c b/fs/ioprio.c
deleted file mode 100644
index e50170ca7c33..000000000000
--- a/fs/ioprio.c
+++ /dev/null
@@ -1,241 +0,0 @@
-/*
- * fs/ioprio.c
- *
- * Copyright (C) 2004 Jens Axboe <axboe@kernel.dk>
- *
- * Helper functions for setting/querying io priorities of processes. The
- * system calls closely mimmick getpriority/setpriority, see the man page for
- * those. The prio argument is a composite of prio class and prio data, where
- * the data argument has meaning within that class. The standard scheduling
- * classes have 8 distinct prio levels, with 0 being the highest prio and 7
- * being the lowest.
- *
- * IOW, setting BE scheduling class with prio 2 is done ala:
- *
- * unsigned int prio = (IOPRIO_CLASS_BE << IOPRIO_CLASS_SHIFT) | 2;
- *
- * ioprio_set(PRIO_PROCESS, pid, prio);
- *
- * See also Documentation/block/ioprio.txt
- *
- */
-#include <linux/gfp.h>
-#include <linux/kernel.h>
-#include <linux/export.h>
-#include <linux/ioprio.h>
-#include <linux/blkdev.h>
-#include <linux/capability.h>
-#include <linux/syscalls.h>
-#include <linux/security.h>
-#include <linux/pid_namespace.h>
-
-int set_task_ioprio(struct task_struct *task, int ioprio)
-{
- int err;
- struct io_context *ioc;
- const struct cred *cred = current_cred(), *tcred;
-
- rcu_read_lock();
- tcred = __task_cred(task);
- if (!uid_eq(tcred->uid, cred->euid) &&
- !uid_eq(tcred->uid, cred->uid) && !capable(CAP_SYS_NICE)) {
- rcu_read_unlock();
- return -EPERM;
- }
- rcu_read_unlock();
-
- err = security_task_setioprio(task, ioprio);
- if (err)
- return err;
-
- ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE);
- if (ioc) {
- ioc->ioprio = ioprio;
- put_io_context(ioc);
- }
-
- return err;
-}
-EXPORT_SYMBOL_GPL(set_task_ioprio);
-
-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;
- kuid_t uid;
- 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:
- uid = make_kuid(current_user_ns(), who);
- if (!uid_valid(uid))
- break;
- if (!who)
- user = current_user();
- else
- user = find_user(uid);
-
- if (!user)
- break;
-
- do_each_thread(g, p) {
- if (!uid_eq(task_uid(p), uid))
- 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;
- }
-
- rcu_read_unlock();
- return ret;
-}
-
-static int get_task_ioprio(struct task_struct *p)
-{
- int ret;
-
- ret = security_task_getioprio(p);
- if (ret)
- goto out;
- ret = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_NONE, IOPRIO_NORM);
- if (p->io_context)
- ret = p->io_context->ioprio;
-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 (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;
-}
-
-SYSCALL_DEFINE2(ioprio_get, int, which, int, who)
-{
- struct task_struct *g, *p;
- struct user_struct *user;
- struct pid *pgrp;
- kuid_t uid;
- int ret = -ESRCH;
- int tmpio;
-
- rcu_read_lock();
- switch (which) {
- case IOPRIO_WHO_PROCESS:
- if (!who)
- p = current;
- else
- p = find_task_by_vpid(who);
- if (p)
- ret = get_task_ioprio(p);
- break;
- case IOPRIO_WHO_PGRP:
- if (!who)
- pgrp = task_pgrp(current);
- else
- pgrp = find_vpid(who);
- do_each_pid_thread(pgrp, PIDTYPE_PGID, p) {
- tmpio = get_task_ioprio(p);
- if (tmpio < 0)
- continue;
- if (ret == -ESRCH)
- ret = tmpio;
- else
- ret = ioprio_best(ret, tmpio);
- } while_each_pid_thread(pgrp, PIDTYPE_PGID, p);
- break;
- case IOPRIO_WHO_USER:
- uid = make_kuid(current_user_ns(), who);
- if (!who)
- user = current_user();
- else
- user = find_user(uid);
-
- if (!user)
- break;
-
- do_each_thread(g, p) {
- if (!uid_eq(task_uid(p), user->uid))
- continue;
- tmpio = get_task_ioprio(p);
- if (tmpio < 0)
- continue;
- if (ret == -ESRCH)
- ret = tmpio;
- else
- ret = ioprio_best(ret, tmpio);
- } while_each_thread(g, p);
-
- if (who)
- free_uid(user);
- break;
- default:
- ret = -EINVAL;
- }
-
- rcu_read_unlock();
- return ret;
-}