From 2667bcbbd5ed71f29b78ba69f059dbc450e07faf Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 19 May 2014 11:02:18 -0600 Subject: block: move ioprio.c from fs/ to block/ Like commit f9c78b2b, move this block related file outside of fs/ and into the core block directory, block/. Signed-off-by: Jens Axboe --- block/Makefile | 3 +- block/ioprio.c | 241 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/Makefile | 2 +- fs/ioprio.c | 241 --------------------------------------------------------- 4 files changed, 244 insertions(+), 243 deletions(-) create mode 100644 block/ioprio.c delete mode 100644 fs/ioprio.c diff --git a/block/Makefile b/block/Makefile index 506a0c5..b4c4d3b 100644 --- a/block/Makefile +++ b/block/Makefile @@ -7,7 +7,8 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-tag.o blk-sysfs.o \ blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \ blk-iopoll.o blk-lib.o blk-mq.o blk-mq-tag.o \ blk-mq-sysfs.o blk-mq-cpu.o blk-mq-cpumap.o ioctl.o \ - genhd.o scsi_ioctl.o partition-generic.o partitions/ + genhd.o scsi_ioctl.o partition-generic.o ioprio.o \ + partitions/ obj-$(CONFIG_BLK_DEV_BSG) += bsg.o obj-$(CONFIG_BLK_DEV_BSGLIB) += bsg-lib.o diff --git a/block/ioprio.c b/block/ioprio.c new file mode 100644 index 0000000..e50170c --- /dev/null +++ b/block/ioprio.c @@ -0,0 +1,241 @@ +/* + * fs/ioprio.c + * + * Copyright (C) 2004 Jens Axboe + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include + +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; +} diff --git a/fs/Makefile b/fs/Makefile index 1ed9eab..4030cbf 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -14,7 +14,7 @@ obj-y := open.o read_write.o file_table.o super.o \ stack.o fs_struct.o statfs.o ifeq ($(CONFIG_BLOCK),y) -obj-y += buffer.o block_dev.o direct-io.o mpage.o ioprio.o +obj-y += buffer.o block_dev.o direct-io.o mpage.o else obj-y += no-block.o endif diff --git a/fs/ioprio.c b/fs/ioprio.c deleted file mode 100644 index e50170c..0000000 --- a/fs/ioprio.c +++ /dev/null @@ -1,241 +0,0 @@ -/* - * fs/ioprio.c - * - * Copyright (C) 2004 Jens Axboe - * - * 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 -#include -#include -#include -#include -#include -#include -#include -#include - -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; -} -- cgit v1.1