The current job /proc ioctl interface is really a fake-syscall interface.
We only did that so that our product didn't have to lock into a syscall
number that would eventually be used by something else.
The easiest thing for us would probably be to turn it back into a system
call, if that would be acceptable for inclusion into the kernel. We're
open to other job interfaces, such as a real /proc character interface,
or a new virtual filesystem, or a device driver using ioctls.
Since we don't do lots of user interfaces, and changing them later is
harder once they're in use, we'd like to get it right. Any guideance
people have about what flavor of interface might be appropriate in this
case would be appreciated.
John
On Tue, Aug 31, 2004 at 03:39:18PM -0700, Limin Gu wrote:
> Hello,
>
> Generally speaking, a job is a group of related processes all
> descended from a point of entry process and identified by a unique job
> identifier (jid). A job can contain multiple process groups or
> sessions, and all processes in one of these subgroups can only be
> contained within a single job.
>
> We (SGI) have been running the PAGG/JOB/CSA stack on our linux
> platform (Altix) for serveral years now. Now we are trying to push the
> whole stack to community kernel. PAGG is getting accepted into
> 2.6.8-rc3-mm2 , and the interest on CSA is growing, the discussion
> thread is at
> http://www.ussg.iu.edu/hypermail/linux/kernel/0408.3/0641.html
>
> Between PAGG and CSA is the JOB kernel module. I have posted the Job
> kernel module patch a couple of times. As Chris Wright kindly pointed
> out, job uses iotcl on /proc/job binary interface, which is not an
> appropriate kernel and user space communication interface in linux,
> but instead job should promote to use a real syscall or should
> implement a file system for it.
>
> Actually Job was using system calls initially before we changed it to
> ioctl's on /proc for the reason that job does not have a system call
> number. Also it seems to me that a file system is not very suitable to
> the functionality of Job provides.
>
> I am willing to make the necessary changes to get Job accepted into
> the community kernel. I hope I can get some help on how to improving
> the job kernel/user interface, system call, file system, device
> driver, or whatever is appropriate for job's functionality. Any
> suggestion or comment will be appreciated.
>
> I attach the job patch for 2.6.8 here again for your convinence, and
> always you can find more about job user library and command at
> http://oss.sgi.com/projects/pagg
>
> Thank you!
>
> Signed-off-by: Limin Gu <[email protected]>
>
> --
> Limin Gu - Linux System Software
> Silicon Graphics Inc., Mountain View, CA
>
>
>
>
>
>
>
>
>
> Index: linux/Documentation/job.txt
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux/Documentation/job.txt 2004-08-16 10:42:38.000000000 -0500
> @@ -0,0 +1,104 @@
> +Linux Jobs - A Process Aggregate (PAGG) Module
> +----------------------------------------------
> +
> +1. Overview
> +
> +This document provides two additional sections. Section 2 provides a
> +listing of the manual page that describes the particulars of the Linux
> +job implementation. Section 3 provides some information about using
> +the user job library to interface to jobs.
> +
> +2. Job Man Page
> +
> +
> +JOB(7) Linux User's Manual JOB(7)
> +
> +
> +NAME
> + job - Linux Jobs kernel module overview
> +
> +DESCRIPTION
> + A job is a group of related processes all descended from a
> + point of entry process and identified by a unique job
> + identifier (jid). A job can contain multiple process
> + groups or sessions, and all processes in one of these sub-
> + groups can only be contained within a single job.
> +
> + The primary purpose for having jobs is to provide job
> + based resource limits. The current implementation only
> + provides the job container and resource limits will be
> + provided in a later implementation. When an implementa-
> + tion that provides job limits is available, this descrip-
> + tion will be expanded to provide further explanation of
> + job based limits.
> +
> + Not every process on the system is part of a job. That
> + is, only processes which are started by a login initiator
> + like login, rlogin, rsh and so on, get assigned a job ID.
> + In the Linux environment, jobs are created via a PAM mod-
> + ule.
> +
> + Jobs on Linux are provided using a loadable kernel module.
> + Linux jobs have the following characteristics:
> +
> + o A job is an inescapable container. A process cannot
> + leave the job nor can a new process be created outside
> + the job without explicit action, that is, a system
> + call with root privilege.
> +
> + o Each new process inherits the jid and limits [when
> + implemented] from its parent process.
> +
> + o All point of entry processes (job initiators) create a
> + new job and set the job limits [when implemented]
> + appropriately.
> +
> + o Job initiation on Linux is performed via a PAM session
> + module.
> +
> + o The job initiator performs authentication and security
> + checks.
> +
> + o Users can raise and lower their own job limits within
> + maximum values specified by the system administrator
> + [when implemented].
> +
> + o Not all processes on a system need be members of a job.
> +
> + o The process control initialization process (init(1M))
> + and startup scripts called by init are not part of a
> + job.
> +
> +
> + Job initiators can be categorized as either interactive or
> + batch processes. Limit domain names are defined by the
> + system administrator when the user limits database (ULDB)
> + is created. [The ULDB will be implemented in conjunction
> + with future job limits work.]
> +
> + Note: The existing command jobs(1) applies to shell "jobs"
> + and it is not related to the Linux Kernel Module jobs.
> + The at(1), atd(8), atq(1), batch(1), atrun(8), atrm(1))
> + man pages refer to shell scripts as a job. a shell
> + script.
> +
> +SEE ALSO
> + job(1), jwait(1), jstat(1), jkill(1)
> +
> +
> +
> +
> +
> +
> +
> +
> +
> +3. User Job Library
> +
> +For developers who wish to make software using Linux Jobs, there exists
> +a user job library. This library contains functions for obtaining information
> +about running jobs, creating jobs, detaching, etc.
> +
> +The library is part of the job package and can be obtained from oss.sgi.com
> +using anonymous ftp. Look in the /projects/pagg/download directory. See the
> +README in the job source package for more information.
> Index: linux/include/linux/job.h
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux/include/linux/job.h 2004-08-16 10:42:38.000000000 -0500
> @@ -0,0 +1,123 @@
> +/*
> + * PAGG Job kernel definitions & interfaces
> + *
> + *
> + * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + *
> + * Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane,
> + * Mountain View, CA 94043, or:
> + *
> + * http://www.sgi.com
> + *
> + * For further information regarding this notice, see:
> + *
> + * http://oss.sgi.com/projects/GenInfo/NoticeExplan
> + */
> +
> +/*
> + * Description: This file, include/linux/job.h, contains the data
> + * structure definitions and functions prototypes used
> + * by other kernel bits that communicate with the job
> + * module. One such example is Comprehensive System
> + * Accounting (CSA).
> + */
> +
> +#ifndef _LINUX_JOB_H
> +#define _LINUX_JOB_H
> +
> +/*
> + * ================
> + * GENERAL USE INFO
> + * ================
> + */
> +
> +/*
> + * The job start/stop events: These will identify the
> + * the reason the jobstart and jobend callbacks are being
> + * called.
> + */
> +enum {
> + JOB_EVENT_IGNORE = 0,
> + JOB_EVENT_START = 1,
> + JOB_EVENT_RESTART = 2,
> + JOB_EVENT_END = 3,
> +};
> +
> +
> +/*
> + * =========================================
> + * INTERFACE INFO FOR ACCOUNTING SUBSCRIBERS
> + * =========================================
> + */
> +
> +/* To register as a job dependent accounting module */
> +struct job_acctmod {
> + int type; /* CSA or something else */
> + int (*jobstart)(int event, void *data);
> + int (*jobend)(int event, void *data);
> + struct module *module;
> +};
> +
> +
> +/*
> + * Subscriber type: Each module that registers as a accounting data
> + * "subscriber" has to have a type. This type will identify the
> + * the appropriate structs and macros to use when exchanging data.
> + */
> +#define JOB_ACCT_CSA 0
> +#define JOB_ACCT_COUNT 1 /* Number of entries available */
> +
> +
> +/*
> + * --------------
> + * CSA ACCOUNTING
> + * --------------
> + */
> +
> +/*
> + * For data exchange betwee job and csa. The embedded defines
> + * identify the sub-fields
> + */
> +struct job_csa {
> +#define JOB_CSA_JID 001
> + u64 job_id;
> +#define JOB_CSA_UID 002
> + uid_t job_uid;
> +#define JOB_CSA_START 004
> + time_t job_start;
> +#define JOB_CSA_COREHIMEM 010
> + u64 job_corehimem;
> +#define JOB_CSA_VIRTHIMEM 020
> + u64 job_virthimem;
> +#define JOB_CSA_ACCTFILE 040
> + struct file *job_acctfile;
> +};
> +
> +
> +/*
> + * ===================
> + * FUNCTION PROTOTYPES
> + * ===================
> + */
> +int job_register_acct(struct job_acctmod *);
> +int job_unregister_acct(struct job_acctmod *);
> +u64 job_getjid(struct task_struct *);
> +int job_getacct(u64, int, void *);
> +int job_setacct(u64, int, int, void *);
> +
> +#endif /* _LINUX_JOB_H */
> Index: linux/include/linux/paggctl.h
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux/include/linux/paggctl.h 2004-08-16 10:42:38.000000000 -0500
> @@ -0,0 +1,179 @@
> +/*
> + *
> + * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + *
> + * Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane,
> + * Mountain View, CA 94043, or:
> + *
> + * http://www.sgi.com
> + *
> + * For further information regarding this notice, see:
> + *
> + * http://oss.sgi.com/projects/GenInfo/NoticeExplan
> + *
> + *
> + * Description: This file, include/linux/paggctl.h, contains the data
> + * definitions used by job to communicate with pagg via the /proc/job
> + * ioctl interface.
> + *
> + */
> +
> +#ifndef _LINUX_PAGGCTL_H
> +#define _LINUX_PAGGCTL_H
> +#ifndef __KERNEL__
> +#include <stdint.h>
> +#include <sys/types.h>
> +#include <asm/unistd.h>
> +#endif
> +
> +#define PAGG_NAMELN 32 /* Max chars in PAGG module name */
> +#define PAGG_NAMESTR PAGG_NAMELN+1 /* PAGG mod name string including
> + * room for end-of-string = '\0' */
> +
> +/*
> + * ====================
> + * JOB PAGG definitions
> + * ====================
> + */
> +#define PAGG_JOB "job" /* PAGG module identifier string */
> +
> +
> +
> +/*
> + * ================
> + * KERNEL INTERFACE
> + * ================
> + */
> +#define JOB_PROC_ENTRY "job" /* /proc entry name */
> +#define JOB_IOCTL_NUM 'A'
> +
> +
> +/*
> + *
> + * Define ioctl options available in the job module
> + *
> + */
> +
> +#define JOB_NOOP _IOWR(JOB_IOCTL_NUM, 0, void *) /* No-op options */
> +
> +#define JOB_CREATE _IOWR(JOB_IOCTL_NUM, 1, void *) /* Create a job - uid = 0 only */
> +#define JOB_ATTACH _IOWR(JOB_IOCTL_NUM, 2, void *) /* RESERVED */
> +#define JOB_DETACH _IOWR(JOB_IOCTL_NUM, 3, void *) /* RESERVED */
> +#define JOB_GETJID _IOWR(JOB_IOCTL_NUM, 4, void *) /* Get Job ID for specificed pid */
> +#define JOB_WAITJID _IOWR(JOB_IOCTL_NUM, 5, void *) /* Wait for job to complete */
> +#define JOB_KILLJID _IOWR(JOB_IOCTL_NUM, 6, void *) /* Send signal to job */
> +#define JOB_GETJIDCNT _IOWR(JOB_IOCTL_NUM, 9, void *) /* Get number of JIDs on system */
> +#define JOB_GETJIDLST _IOWR(JOB_IOCTL_NUM, 10, void *) /* Get list of JIDs on system */
> +#define JOB_GETPIDCNT _IOWR(JOB_IOCTL_NUM, 11, void *) /* Get number of PIDs in JID */
> +#define JOB_GETPIDLST _IOWR(JOB_IOCTL_NUM, 12, void *) /* Get list of PIDs in JID */
> +#define JOB_SETJLIMIT _IOWR(JOB_IOCTL_NUM, 13, void *) /* Future: set job limits info */
> +#define JOB_GETJLIMIT _IOWR(JOB_IOCTL_NUM, 14, void *) /* Future: get job limits info */
> +#define JOB_GETJUSAGE _IOWR(JOB_IOCTL_NUM, 15, void *) /* Future: get job res. usage */
> +#define JOB_FREE _IOWR(JOB_IOCTL_NUM, 16, void *) /* Future: Free job entry */
> +#define JOB_GETUSER _IOWR(JOB_IOCTL_NUM, 17, void *) /* Get owner for job */
> +#define JOB_GETPRIMEPID _IOWR(JOB_IOCTL_NUM, 18, void *) /* Get prime pid for job */
> +#define JOB_SETHID _IOWR(JOB_IOCTL_NUM, 19, void *) /* Set HID for jid values */
> +#define JOB_DETACHJID _IOWR(JOB_IOCTL_NUM, 20, void *) /* Detach all tasks from job */
> +#define JOB_DETACHPID _IOWR(JOB_IOCTL_NUM, 21, void *) /* Detach a task from job */
> +#define JOB_OPT_MAX _IOWR(JOB_IOCTL_NUM, 22 , void *) /* Should always be highest number */
> +
> +
> +/*
> + * Define ioctl request structures for job module
> + */
> +
> +struct job_create {
> + u64 r_jid; /* Return value of JID */
> + u64 jid; /* Jid value requested */
> + int user; /* UID of user associated with job */
> + int options;/* creation options - unused */
> +};
> +
> +
> +struct job_getjid {
> + u64 r_jid; /* Returned value of JID */
> + pid_t pid; /* Info requested for PID */
> +};
> +
> +
> +struct job_waitjid {
> + u64 r_jid; /* Returned value of JID */
> + u64 jid; /* Waiting on specified JID */
> + int stat; /* Status information on JID */
> + int options;/* Waiting options */
> +};
> +
> +
> +struct job_killjid {
> + int r_val; /* Return value of kill request */
> + u64 jid; /* Sending signal to all PIDs in JID */
> + int sig; /* Signal to send */
> +};
> +
> +
> +struct job_jidcnt {
> + int r_val; /* Number of JIDs on system */
> +};
> +
> +
> +struct job_jidlst {
> + int r_val; /* Number of JIDs in list */
> + u64 *jid; /* List of JIDs */
> +};
> +
> +
> +struct job_pidcnt {
> + int r_val; /* Number of PIDs in JID */
> + u64 jid; /* Getting count of JID */
> +};
> +
> +
> +struct job_pidlst {
> + int r_val; /* Number of PIDs in list */
> + pid_t *pid; /* List of PIDs */
> + u64 jid;
> +};
> +
> +
> +struct job_user {
> + int r_user; /* The UID of the owning user */
> + u64 jid; /* Get the UID for this job */
> +};
> +
> +struct job_primepid {
> + pid_t r_pid; /* The prime pid */
> + u64 jid; /* Get the prime pid for this job */
> +};
> +
> +struct job_sethid {
> + unsigned long r_hid; /* Value that was set */
> + unsigned long hid; /* Value to set to */
> +};
> +
> +
> +struct job_detachjid {
> + int r_val; /* Number of tasks detached from job */
> + u64 jid; /* Job to detach processes from */
> +};
> +
> +struct job_detachpid {
> + u64 r_jid; /* Jod ID task was attached to */
> + pid_t pid; /* Task to detach from job */
> +};
> +
> +#endif /* _LINUX_PAGGCTL_H */
> Index: linux/init/Kconfig
> ===================================================================
> --- linux.orig/init/Kconfig 2004-08-16 10:41:23.000000000 -0500
> +++ linux/init/Kconfig 2004-08-16 10:42:38.000000000 -0500
> @@ -133,6 +133,31 @@
> Linux Jobs module and the Linux Array Sessions module. If you will not
> be using such modules, say N.
>
> +config PAGG_JOB
> + tristate " Process aggregate based jobs"
> + depends on PAGG
> + help
> + The Job feature implements a type of process aggregate,
> + or grouping. A job is the collection of all processes that
> + are descended from a point-of-entry process. Examples of such
> + points-of-entry include telnet, rlogin, and console logins.
> + A job differs from a session and process group since the job
> + container (or group) is inescapable. Only root level processes,
> + or those with the CAP_SYS_RESOURCE capability, can create new jobs
> + or escape from a job.
> +
> + A job is identified by a unique job identifier (jid). Currently,
> + that jid can be used to obtain status information about the job
> + and the processes it contians. The jid can also be used to send
> + signals to all processes contained in the job. In addition,
> + other processes can wait for the completion of a job - the event
> + where the last process contained in the job has exited.
> +
> + If you want to compile support for jobs into the kernel, select
> + this entry using Y. If you want the support for jobs provided as
> + a module, select this entry using M. If you do not want support
> + for jobs, select N.
> +
> config SYSCTL
> bool "Sysctl support"
> ---help---
> Index: linux/kernel/job.c
> ===================================================================
> --- /dev/null 1970-01-01 00:00:00.000000000 +0000
> +++ linux/kernel/job.c 2004-08-16 10:42:38.000000000 -0500
> @@ -0,0 +1,2052 @@
> +/*
> + * Linux Job kernel module
> + *
> + *
> + * Copyright (c) 2000-2004 Silicon Graphics, Inc. All Rights Reserved.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
> + *
> + *
> + * Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane,
> + * Mountain View, CA 94043, or:
> + *
> + * http://www.sgi.com
> + *
> + * For further information regarding this notice, see:
> + *
> + * http://oss.sgi.com/projects/GenInfo/NoticeExplan
> + */
> +
> +/*
> + * Description: This file implements a type of process grouping called jobs.
> + * For further information about jobs, consult the file
> + * Documentation/job.txt. Jobs are implemented as a type of PAGG
> + * (process aggregate). For further information about PAGGs,
> + * consult the file Documentation/pagg.txt.
> + */
> +
> +/*
> + * LOCKING INFO
> + *
> + * There are currently two levels of locking in this module. So, we
> + * have two classes of locks:
> + *
> + * (1) job table lock (always, job_table_sem)
> + * (2) job entry lock (usually, job->sem)
> + *
> + * Most of the locking used is read/write sempahores. In rare cases, a
> + * spinlock is also used. Those cases requiring a spinlock concern when the
> + * tasklist_lock must be locked (such as when looping over all tasks on the
> + * system).
> + *
> + * There is only one job_table_sem. There is a job->sem for each job
> + * entry in the job_table. This job module is a PAGG module (Process
> + * Aggregation). Each task has a special lock that protects its PAGG
> + * information - this is called the pagg list lock. There are special macros
> + * used to lock/unlock a task's pagg list lock. The pagg list lock is really
> + * a semaphore.
> + *
> + * Purpose:
> + *
> + * (1) The job_table_sem protects all entries in the table.
> + * (2) The job->sem protects all data and task attachments for the job.
> + *
> + * Truths we hold to be self-evident:
> + *
> + * Only the holder of a write lock for the job_table_lock may add or
> + * delete a job entry from the job_table. The job_table includes all job
> + * entries in the hash table and chains off the hash table locations.
> + *
> + * Only the holder of a write lock for a job->lock may attach or detach
> + * processes/tasks from the attached list for the job.
> + *
> + * If you hold a read lock of job_table_lock, you can assume that the
> + * job entries in the table will not change. The link pointers for
> + * the chains of job entries will not change, the job ID (jid) value
> + * will not change, and data changes will be (mostly) atomic.
> + *
> + * If you hold a read lock of a job->lock, you can assume that the
> + * attachments to the job will not change. The link pointers for the
> + * attachment list will not change and the attachments will not change.
> + *
> + * If you are going to grab nested locks, the nesting order is:
> + *
> + * down_write/up_write/down_read/up_read(&task->pagg_sem)
> + * job_table_sem
> + * job->sem
> + *
> + * However, it is not strictly necessary to down the job_table_sem
> + * before downing job->sem.
> + *
> + * Also, the nesting order allows you to lock in this order:
> + *
> + * down_write/up_write/down_read/up_read(&task->pagg_sem)
> + * job->sem
> + *
> + * without locking job_table_sem between the two.
> + *
> + */
> +
> +/* standard for kernel modules */
> +#include <linux/config.h>
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/kmod.h>
> +#include <linux/init.h>
> +#include <linux/list.h>
> +
> +#include <asm/uaccess.h> /* for get_user & put_user */
> +
> +#include <linux/sched.h> /* for current */
> +#include <linux/tty.h> /* for the tty declarations */
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +
> +#include <linux/proc_fs.h>
> +
> +#include <linux/string.h>
> +#include <asm/semaphore.h>
> +
> +#include <linux/pagg.h> /* to use pagg hooks */
> +#include <linux/job.h>
> +#include <linux/paggctl.h>
> +
> +MODULE_AUTHOR("Silicon Graphics, Inc.");
> +MODULE_DESCRIPTION("PAGG-based inescapable jobs");
> +MODULE_LICENSE("GPL");
> +
> +#define HASH_SIZE 1024
> +
> +/* The states for a job */
> +#define FETAL 1 /* being born, not ready for attachments yet */
> +#define RUNNING 2 /* Running job */
> +#define STOPPED 3 /* Stopped job */
> +#define ZOMBIE 4 /* Dead job */
> +
> +/* Job creation tags for the job HID (host ID) */
> +#define DISABLED 0xffffffff /* New job creation disabled */
> +#define LOCAL 0x0 /* Only creating local sys jobs */
> +
> +
> +#ifdef __BIG_ENDIAN
> +#define iptr_hid(ll) ((u32 *)&(ll))
> +#define iptr_sid(ll) (((u32 *)(&(ll) + 1)) - 1)
> +#else /* __LITTLE_ENDIAN */
> +#define iptr_hid(ll) (((u32 *)(&(ll) + 1)) - 1)
> +#define iptr_sid(ll) ((u32 *)&(ll))
> +#endif /* __BIG_ENDIAN */
> +
> +#define jid_hash(ll) (*(iptr_sid(ll)) % HASH_SIZE)
> +
> +
> +/* Job info entry for member tasks */
> +struct job_attach {
> + struct task_struct *task; /* task we are attaching to job */
> + struct pagg *pagg; /* our pagg entry in the task */
> + struct job_entry *job; /* the job we are attaching task to */
> + struct list_head entry; /* list stuff */
> +};
> +
> +struct job_waitinfo {
> + int status; /* For tasks waiting on job exit */
> +};
> +
> +struct job_csainfo {
> + u64 corehimem; /* Accounting - highpoint, phys mem */
> + u64 virthimem; /* Accounting - highpoint, virt mem */
> + struct file *acctfile; /* The accounting file for job */
> +};
> +
> +/* Job table entry type */
> +struct job_entry {
> + u64 jid; /* Our job ID */
> + int refcnt; /* Number of tasks attached to job */
> + int state; /* State of job - RUNNING,... */
> + struct rw_semaphore sem; /* lock for the job */
> + uid_t user; /* user that owns the job */
> + time_t start; /* When the job began */
> + struct job_csainfo csa; /* CSA accounting info */
> + wait_queue_head_t zombie; /* queue last task - during wait */
> + wait_queue_head_t wait; /* queue of tasks waiting on job */
> + int waitcnt; /* Number of tasks waiting on job */
> + struct job_waitinfo waitinfo; /* Status info for waiting tasks */
> + struct list_head attached; /* List of attached tasks */
> + struct list_head entry; /* List of other jobs - same hash */
> +};
> +
> +
> +/* Job container tables */
> +static struct list_head job_table[HASH_SIZE];
> +static int job_table_refcnt = 0;
> +static DECLARE_RWSEM(job_table_sem);
> +
> +
> +/* Accounting subscriber list */
> +static struct job_acctmod *acct_list[JOB_ACCT_COUNT];
> +static DECLARE_RWSEM(acct_list_sem);
> +
> +
> +/* Host ID for the localhost */
> +static u32 jid_hid = DISABLED;
> +
> +static char *hid = NULL;
> +MODULE_PARM(hid, "s");
> +
> +/* Function prototypes */
> +static int job_sys_create(struct job_create *);
> +static int job_sys_getjid(struct job_getjid *);
> +static int job_sys_waitjid(struct job_waitjid *);
> +static int job_sys_killjid(struct job_killjid *);
> +static int job_sys_getjidcnt(struct job_jidcnt *);
> +static int job_sys_getjidlst(struct job_jidlst *);
> +static int job_sys_getpidcnt(struct job_pidcnt *);
> +static int job_sys_getpidlst(struct job_pidlst *);
> +static int job_sys_getuser(struct job_user *);
> +static int job_sys_getprimepid(struct job_primepid *);
> +static int job_sys_sethid(struct job_sethid *);
> +static int job_sys_detachjid(struct job_detachjid *);
> +static int job_sys_detachpid(struct job_detachpid *);
> +static int job_attach(struct task_struct *, struct pagg *, void *);
> +static void job_detach(struct task_struct *, struct pagg *);
> +static struct job_entry *job_getjob(u64 jid);
> +static int job_syscall(unsigned int, unsigned long);
> +
> +u64 job_getjid(struct task_struct *);
> +
> +int job_ioctl(struct inode *, struct file *, unsigned int, unsigned long);
> +
> +/* Job container kernel pagg entry */
> +static struct pagg_hook pagg_hook = {
> + .module = THIS_MODULE,
> + .name = PAGG_JOB,
> + .data = &job_table,
> + .init = NULL,
> + .entry = LIST_HEAD_INIT(pagg_hook.entry),
> + .attach = job_attach,
> + .detach = job_detach,
> + .exec = NULL,
> +};
> +
> +/* proc dir entry */
> +struct proc_dir_entry *job_proc_entry;
> +
> +/* file operations for proc file */
> +static struct file_operations job_file_ops = {
> + .owner = THIS_MODULE,
> + .ioctl = job_ioctl
> +};
> +
> +#ifdef DEBUG
> +
> +#define DBG_PRINTINIT(s) \
> + char *dbg_fname = s
> +
> +#define DBG_PRINTENTRY() \
> +do { \
> + printk(KERN_DEBUG "job: %s: entry\n", dbg_fname); \
> +} while(0)
> +
> +#define DBG_PRINTEXIT(c) \
> +do { \
> + printk(KERN_DEBUG "job: %s: exit, code = %d\n", dbg_fname, c); \
> +} while(0)
> +
> +/* write lock semaphore */
> +#define JOB_WLOCK(l) \
> +do { \
> + printk(KERN_DEBUG "job: wlock = %p\n", l); \
> + down_write(l); \
> +} while(0);
> +
> +/* write unlock semaphore */
> +#define JOB_WUNLOCK(l) \
> +do { \
> + printk(KERN_DEBUG "job: wunlock = %p\n", l); \
> + up_write(l); \
> +} while(0);
> +
> +/* read lock semaphore */
> +#define JOB_RLOCK(l) \
> +do { \
> + printk(KERN_DEBUG "job: rlock = %p\n", l); \
> + down_read(l); \
> +} while(0);
> +
> +/* read unlock semaphore */
> +#define JOB_RUNLOCK(l) \
> +do { \
> + printk(KERN_DEBUG "job: runlock = %p\n", l); \
> + up_read(l); \
> +} while(0);
> +
> +
> +#else /* #ifdef DEBUG */
> +
> +#define DBG_PRINTINIT(s)
> +
> +#define DBG_PRINTENTRY() \
> +do { \
> +} while(0)
> +
> +#define DBG_PRINTEXIT(c) \
> +do { \
> +} while(0)
> +
> +/* write lock semaphore */
> +#define JOB_WLOCK(l) \
> +do { \
> + down_write(l); \
> +} while(0);
> +
> +/* write unlock semaphore */
> +#define JOB_WUNLOCK(l) \
> +do { \
> + up_write(l); \
> +} while(0);
> +
> +/* read lock semaphore */
> +#define JOB_RLOCK(l) \
> +do { \
> + down_read(l); \
> +} while(0);
> +
> +/* read unlock semaphore */
> +#define JOB_RUNLOCK(l) \
> +do { \
> + up_read(l); \
> +} while(0);
> +
> +
> +#endif /* #ifdef DEBUG */
> +
> +
> +
> +/*
> + * job__getjob
> + *
> + * Given a jid value, find the entry in the job_table and return a pointer
> + * to the job entry or NULL if not found.
> + *
> + * You should normally JOB_RLOCK the job_table_sem before calling this
> + * function.
> + */
> +struct job_entry *
> +job_getjob(u64 jid)
> +{
> + struct list_head *entry = NULL;
> + struct job_entry *tjob = NULL;
> + struct job_entry *job = NULL;
> +
> + list_for_each(entry, &job_table[ jid_hash(jid) ]) {
> + tjob = list_entry(entry, struct job_entry, entry);
> + if (tjob->jid == jid) {
> + job = tjob;
> + break;
> + }
> + }
> + return job;
> +}
> +
> +
> +/*
> + * job_attach
> + *
> + * Attach the task to the job specified in the target data (old_data).
> + * This function will add the task to the list of attached tasks for the job.
> + * In addition, a link from the task to the job is created and added to the
> + * task via the data pointer reference.
> + *
> + * The process that owns the target data should be at least read locked (using
> + * down_read(&task->pagg_sem)) during this call. This help in ensuring
> + * that the job cannot be removed since at least one process will
> + * still be referencing the job (the one owning the target_data).
> + *
> + * It is expected that this function will be called from within the
> + * pagg_attach() function in the kernel, when forking (do_fork) a child
> + * process represented by task.
> + *
> + * If this function is called form some other point, then it is possible that
> + * task and data could be altered while going through this function. In such
> + * a case, the caller should also lock the pagg list for the task
> + * task_struct.
> + *
> + * the function returns 0 upon success, and -1 upon failure.
> + */
> +static int
> +job_attach(struct task_struct *task, struct pagg *new_pagg,
> + void *old_data)
> +{
> + struct job_entry *job = ((struct job_attach *)old_data)->job;
> + struct job_attach *attached = NULL;
> + int errcode = 0;
> + DBG_PRINTINIT("job_attach");
> +
> + DBG_PRINTENTRY();
> +
> + /*
> + * Lock the job for writing. The task owning target_data has its
> + * pagg_sem locked, so we know there is at least one active reference
> + * to the job - therefore, it cannot have been removed before we
> + * have gotten this write lock established.
> + */
> + JOB_WLOCK(&job->sem);
> +
> + if (job->state == ZOMBIE) {
> + /* If the job is a zombie (dying), bail out of the attach */
> + printk(KERN_WARNING "Attach task(pid=%d) to job"
> + " failed - job is ZOMBIE\n",
> + task->pid);
> + errcode = -EINPROGRESS;
> + JOB_WUNLOCK(&job->sem);
> + goto error_return;
> + }
> +
> +
> + /* Allocate memory that we will need */
> +
> + attached = (struct job_attach *)kmalloc(sizeof(struct job_attach),
> + GFP_KERNEL);
> + if (!attached) {
> + /* error */
> + printk(KERN_ERR "Attach task(pid=%d) to job"
> + " failed on memory error in kernel\n",
> + task->pid);
> + errcode = -ENOMEM;
> + goto error_return;
> + }
> +
> +
> + attached->task = task;
> + attached->pagg = new_pagg;
> + attached->job = job;
> + new_pagg->data = (void *)attached;
> + list_add_tail(&attached->entry, &job->attached);
> + ++job->refcnt;
> +
> + JOB_WUNLOCK(&job->sem);
> +
> + DBG_PRINTEXIT(0);
> + return 0;
> +
> +error_return:
> + DBG_PRINTEXIT(errcode);
> + if (attached) kfree(attached);
> + return errcode;
> +}
> +
> +
> +/*
> + * job_detach
> + *
> + * Detach the task from the job attached to via the pagg reference.
> + * This function will remove the task from the list of attached tasks for the
> + * job specified via the pagg pointer. In addition, the link to the job
> + * provided via the data pointer will also be removed.
> + *
> + * The pagg_list should be write locked for task before entering
> + * this function (using down_write(&task->pagg_sem)).
> + *
> + * the function returns 0 uopn success, and -1 uopn failure.
> + */
> +static void
> +job_detach(struct task_struct *task, struct pagg *pagg)
> +{
> + struct job_attach *attached = ((struct job_attach *)(pagg->data));
> + struct job_entry *job = attached->job;
> + DBG_PRINTINIT("job_detach");
> +
> + DBG_PRINTENTRY();
> +
> + /*
> + * Obtain the lock on the the job_table_sem and the job->sem for
> + * this job.
> + */
> + JOB_WLOCK(&job_table_sem);
> + JOB_WLOCK(&job->sem);
> +
> + job->refcnt--;
> + list_del(&attached->entry);
> + pagg->data = NULL;
> + kfree(attached);
> +
> + if (job->refcnt == 0) {
> + int waitcnt;
> +
> + list_del(&job->entry);
> + --job_table_refcnt;
> +
> + /*
> + * The job is removed from the job_table.
> + * We can remove the job_table_sem now since
> + * nobody can access the job via the table.
> + */
> + JOB_WUNLOCK(&job_table_sem);
> +
> + job->state = ZOMBIE;
> + job->waitinfo.status = task->exit_code;
> +
> + waitcnt = job->waitcnt;
> +
> + /*
> + * Release the job semaphore. You cannot hold
> + * this lock if you want the wakeup to work
> + * properly.
> + */
> + JOB_WUNLOCK(&job->sem);
> +
> + if (waitcnt > 0) {
> + wake_up_interruptible(&job->wait);
> + wait_event(job->zombie, job->waitcnt == 0);
> + }
> +
> + /*
> + * Job is exiting, all processes waiting for job to exit
> + * have been notified. Now we call the accounting
> + * subscribers.
> + */
> +
> +#if defined(CONFIG_CSA) || defined(CONFIG_CSA_MODULE)
> + /* - CSA accounting */
> + if (acct_list[JOB_ACCT_CSA]) {
> + struct job_acctmod *acct = acct_list[JOB_ACCT_CSA];
> + if (acct->module) {
> + if (try_module_get(acct->module) == 0) {
> + printk(KERN_WARNING
> + "job_detach: Tried to get non-living acct module\n");
> + }
> + }
> + if (acct->jobend) {
> + int res = 0;
> + struct job_csa csa;
> +
> + csa.job_id = job->jid;
> + csa.job_uid = job->user;
> + csa.job_start = job->start;
> + csa.job_corehimem = job->csa.corehimem;
> + csa.job_virthimem = job->csa.virthimem;
> + csa.job_acctfile = job->csa.acctfile;
> +
> + res = acct->jobend(JOB_EVENT_END,
> + &csa);
> + if (res) {
> + printk(KERN_WARNING
> + "job_detach: CSA -"
> + " jobend failed.\n");
> + }
> + }
> + if (acct->module)
> + module_put(acct->module);
> + } else {
> + printk(KERN_WARNING "job_detach: CSA - attempt"
> + " to lock CSA module failed.\n");
> + }
> +#endif /* CONFIG_CSA || defined(CONFIG_CSA_MODULE) */
> +
> +
> + /*
> + * Every process attached or waiting on this job should be
> + * detached and finished waiting, so now we can free the
> + * memory for the job.
> + */
> + kfree(job);
> +
> + } else {
> + /* This is case where job->refcnt was greater than 1, so
> + * we were not going to delete the job after the detach.
> + * Therefore, only the job->sem is being held - the
> + * job_table_sem was released earlier.
> + */
> + JOB_WUNLOCK(&job->sem);
> + JOB_WUNLOCK(&job_table_sem);
> + }
> +
> + DBG_PRINTEXIT(0);
> +
> + return;
> +}
> +
> +/*
> + * job_sys_create
> + *
> + * This function is used to create a new job and attache the calling process
> + * to that new job.
> + *
> + * Returns 0 on success, and negative on failure (negative errno value).
> + */
> +static int
> +job_sys_create(struct job_create *create_args)
> +{
> + struct job_create create;
> + struct job_entry *job = NULL;
> + struct job_attach *attached = NULL;
> + struct pagg *pagg = NULL;
> + struct pagg *old_pagg = NULL;
> + int errcode = 0;
> + DBG_PRINTINIT("job_sys_create");
> +
> + DBG_PRINTENTRY();
> +
> + /*
> + * if the job ID - host ID segment is set to DISABLED, we will
> + * not be creating new jobs. We don't mark it as an error, but
> + * the jid value returned will be 0.
> + */
> + if (jid_hid == DISABLED) {
> + errcode = 0;
> + goto error_return;
> + }
> +
> +
> +#if 0 /* XXX - Use if capable is not present */
> + if (current->euid != 0)
> + return -EPERM;
> +#else
> + if (!capable(CAP_SYS_RESOURCE)) {
> + errcode = -EPERM;
> + goto error_return;
> + }
> +#endif
> + if (!create_args) {
> + errcode = -EINVAL;
> + goto error_return;
> + }
> +
> + if (copy_from_user(&create, create_args, sizeof(create))) {
> + errcode = -EFAULT;
> + goto error_return;
> + }
> +
> + /*
> + * Allocate some of the memory we might need, before we start
> + * locking
> + */
> +
> + attached = (struct job_attach *)kmalloc(sizeof(struct job_attach), GFP_KERNEL);
> + if (!attached) {
> + /* error */
> + errcode = -ENOMEM;
> + goto error_return;
> + }
> +
> + job = (struct job_entry *)kmalloc(sizeof(struct job_entry), GFP_KERNEL);
> + if (!job) {
> + /* error */
> + errcode = -ENOMEM;
> + goto error_return;
> + }
> +
> + /* We keep the old pagg around in case we need it in an error condition.
> + * If, for example, a job_getjob call fails because the requested JID is
> + * already in use, we don't want to detach that job. Having this ability
> + * is complicated by the locking.
> + */
> + down_write(¤t->pagg_sem); /* write lock pagg list */
> + old_pagg = pagg_get(current, pagg_hook.name);
> +
> + /*
> + * Lock the job_table and add the pointers for the new job.
> + * Since the job is new, we won't need to lock the job.
> + */
> + JOB_WLOCK(&job_table_sem);
> +
> + /*
> + * Determine if create should use specified JID or one that is
> + * generated.
> + */
> + if (create.jid != 0) {
> + /* We use the specified JID value */
> +
> + if (job_getjob(create.jid)) {
> + /* JID already in use, bail */
> + /* error_return doesn't do JOB_WUNLOCK */
> + JOB_WUNLOCK(&job_table_sem);
> + /* we haven't allocated a new pagg yet so error_return won't unlock
> + * this. We'll unlock here */
> + up_write(¤t->pagg_sem);
> + errcode = -EBUSY;
> + /* error_return doesn't touch old_pagg so we don't detach */
> + goto error_return;
> + } else {
> + /* Using specifiec JID */
> + job->jid = create.jid;
> + }
> +
> + } else {
> +
> + /* We generate a new JID value */
> + *(iptr_hid(job->jid)) = jid_hid;
> + *(iptr_sid(job->jid)) = current->pid;
> + }
> +
> + pagg = pagg_alloc(current, &pagg_hook);
> + if (!pagg) {
> + /* error */
> + up_write(¤t->pagg_sem); /* write unlock pagg list */
> + errcode = -ENOMEM;
> + goto error_return;
> + }
> +
> + /* Initialize job entry values & lists */
> + job->refcnt = 1;
> + job->user = create.user;
> + job->start = jiffies;
> + job->csa.corehimem = 0;
> + job->csa.virthimem = 0;
> + job->csa.acctfile = NULL;
> + job->state = RUNNING;
> + init_rwsem(&job->sem);
> + INIT_LIST_HEAD(&job->attached);
> + list_add_tail(&attached->entry, &job->attached);
> + init_waitqueue_head(&job->wait);
> + init_waitqueue_head(&job->zombie);
> + job->waitcnt = 0;
> + job->waitinfo.status = 0;
> +
> + /* set link from entry in attached list to task and job entry */
> + attached->task = current;
> + attached->job = job;
> + attached->pagg = pagg;
> + pagg->data = (void *)attached;
> +
> + /* Insert new job into front of chain list */
> + list_add_tail(&job->entry, &job_table[ jid_hash(job->jid) ]);;
> + ++job_table_refcnt;
> +
> + JOB_WUNLOCK(&job_table_sem);
> + /* At this point, the possible error conditions where we would need the
> + * old pagg are gone. So we can remove it. We remove after we unlock
> + * because the pagg hook detach function does job table lock of its own.
> + */
> + if (old_pagg) {
> + /*
> + * Detaching paggs for jobs never has a failure case,
> + * so we don't need to worry about error codes.
> + */
> + old_pagg->hook->detach(current, old_pagg);
> + pagg_free(old_pagg);
> + }
> + up_write(¤t->pagg_sem); /* write unlock pagg list */
> +
> + /* Issue callbacks into accounting subscribers */
> +
> +#if defined(CONFIG_CSA) || defined(CONFIG_CSA_MODULE)
> + /* - CSA subscriber */
> + if (acct_list[JOB_ACCT_CSA]) {
> + struct job_acctmod *acct = acct_list[JOB_ACCT_CSA];
> + if (acct->module) {
> + if (try_module_get(acct->module) == 0) {
> + printk(KERN_WARNING
> + "job_sys_create: Tried to get non-living acct module\n");
> + }
> + }
> + if (acct->jobstart) {
> + int res;
> + struct job_csa csa;
> +
> + csa.job_id = job->jid;
> + csa.job_uid = job->user;
> + csa.job_start = job->start;
> + csa.job_corehimem = job->csa.corehimem;
> + csa.job_virthimem = job->csa.virthimem;
> + csa.job_acctfile = job->csa.acctfile;
> +
> + res = acct->jobstart(JOB_EVENT_START, &csa);
> + if (res < 0) {
> + printk(KERN_WARNING "job_sys_create: CSA -"
> + " jobstart failed.\n");
> + }
> + }
> + if (acct->module)
> + module_put(acct->module);
> + }
> +#endif /* CONFIG_CSA || defined(CONFIG_CSA_MODULE) */
> +
> +
> + create.r_jid = job->jid;
> + if (copy_to_user(create_args, &create, sizeof(create))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + DBG_PRINTEXIT(0);
> + return 0;
> +
> +error_return:
> + DBG_PRINTEXIT(errcode);
> + if (attached) kfree(attached);
> + if (job) kfree(job);
> + if (pagg) {
> + pagg->hook->detach(current, pagg); /* detach the pagg */
> + pagg_free(pagg);
> + /* This was locked at pagg_alloc call */
> + up_write(¤t->pagg_sem); /* write unlock pagg list */
> + }
> + create.r_jid = 0;
> + if (copy_to_user(create_args, &create, sizeof(create))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + return errcode;
> +}
> +
> +
> +/*
> + * job_sys_getjid
> + *
> + * Function retrieves the job ID (jid) for the specified process (pid).
> + *
> + * returns 0 on success, negative errno value on exit.
> + */
> +static int
> +job_sys_getjid(struct job_getjid *getjid_args)
> +{
> + struct job_getjid getjid;
> + int errcode = 0;
> + struct task_struct *task;
> + DBG_PRINTINIT("job_sys_getjid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&getjid, getjid_args, sizeof(getjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + /* lock the tasklist until we grab the specific task */
> + read_lock(&tasklist_lock);
> +
> + if (getjid.pid == current->pid) {
> + task = current;
> + } else {
> + task = find_task_by_pid(getjid.pid);
> + }
> + if (task) {
> + get_task_struct(task); /* Ensure the task doesn't vanish on us */
> + read_unlock(&tasklist_lock); /* unlock the task list */
> + getjid.r_jid = job_getjid(task);
> + put_task_struct(task); /* We're done accessing the task */
> + if (getjid.r_jid == 0) {
> + errcode = -ENODATA;
> + }
> + } else {
> + read_unlock(&tasklist_lock);
> + getjid.r_jid = 0;
> + errcode = -ESRCH;
> + }
> +
> +
> + DBG_PRINTEXIT(errcode);
> + if (copy_to_user(getjid_args, &getjid, sizeof(getjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return errcode;
> +}
> +
> +
> +/*
> + * job_sys_waitjid
> + *
> + * This job allows a process to wait until a job exits & it returns the
> + * status information for the last process to exit the job.
> + *
> + * On success returns 0, failure it returns the negative errno value.
> + */
> +static int
> +job_sys_waitjid(struct job_waitjid *waitjid_args)
> +{
> + struct job_waitjid waitjid;
> + struct job_entry *job;
> + int retcode = 0;
> + DBG_PRINTINIT("job_sys_waitjid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&waitjid, waitjid_args, sizeof(waitjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> +
> + waitjid.r_jid = waitjid.stat = 0;
> +
> + if (waitjid.options != 0) {
> + retcode = -EINVAL;
> + goto general_return;
> + }
> +
> + /* Lock the job table so that the current jobs don't change */
> + JOB_RLOCK(&job_table_sem);
> +
> +
> + if ((job = job_getjob(waitjid.jid)) == NULL ) {
> + JOB_RUNLOCK(&job_table_sem);
> + retcode = -ENODATA;
> + goto general_return;
> + }
> +
> + /*
> + * We got the job we need, we can release the job_table_sem
> + */
> + JOB_WLOCK(&job->sem);
> + JOB_RUNLOCK(&job_table_sem);
> +
> + ++job->waitcnt;
> +
> + JOB_WUNLOCK(&job->sem);
> +
> + /* We shouldn't hold any locks at this point! The increment of the
> + * jobs waitcnt will ensure that the job is not removed without
> + * first notifying this current task */
> + retcode = wait_event_interruptible(job->wait,
> + job->refcnt == 0);
> +
> + if (!retcode) {
> + /*
> + * This data is static at this point, we will
> + * not need a lock to read it.
> + */
> + waitjid.stat = job->waitinfo.status;
> + waitjid.r_jid = job->jid;
> + }
> +
> + JOB_WLOCK(&job->sem);
> + --job->waitcnt;
> +
> + if (job->waitcnt == 0) {
> + JOB_WUNLOCK(&job->sem);
> +
> + /*
> + * We shouldn't hold any locks at this point! Else, the
> + * last process in the job will not be able to remove the
> + * job entry.
> + *
> + * That process is stuck waiting for this wake_up, so the
> + * job shouldn't disappear until after this function call.
> + * The job entry is not longer in the job table, so no
> + * other process can get to the entry to foul things up.
> + */
> + wake_up(&job->zombie);
> + } else {
> + JOB_WUNLOCK(&job->sem);
> + }
> +
> +general_return:
> +
> + DBG_PRINTEXIT(retcode);
> + if (copy_to_user(waitjid_args, &waitjid, sizeof(waitjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return retcode;
> +}
> +
> +
> +/*
> + * job_sys_killjid
> + *
> + * This functions allows a signal to be sent to all processes in a job.
> + *
> + * returns 0 on success, negative of errno on failure.
> + */
> +static int
> +job_sys_killjid(struct job_killjid *killjid_args)
> +{
> + struct job_killjid killjid;
> + struct job_entry *job;
> + struct list_head *attached_entry;
> + struct siginfo info;
> + int retcode = 0;
> + DBG_PRINTINIT("job_sys_killjid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&killjid, killjid_args, sizeof(killjid))) {
> + retcode = -EFAULT;
> + goto cleanup_0locks_return;
> + }
> +
> + killjid.r_val = -1;
> +
> + /* A signal of zero is really a status check and is handled as such
> + * by send_sig_info. So we have < 0 instead of <= 0 here.
> + */
> + if (killjid.sig < 0) {
> + retcode = -EINVAL;
> + goto cleanup_0locks_return;
> + }
> +
> + JOB_RLOCK(&job_table_sem);
> + job = job_getjob(killjid.jid);
> + if (!job) {
> + /* Job not found, copy back data & bail with error */
> + retcode = -ENODATA;
> + goto cleanup_1locks_return;
> + }
> +
> + JOB_RLOCK(&job->sem);
> +
> + /*
> + * Check capability to signal job. The signaling user must be
> + * the owner of the job or have CAP_SYS_RESOURCE capability.
> + */
> +#if 0 /* Use this if not capability is available */
> + if (current->uid != 0) {
> +#else
> + if (!capable(CAP_SYS_RESOURCE)) {
> +#endif
> + if (current->uid != job->user) {
> + retcode = -EPERM;
> + goto cleanup_2locks_return;
> + }
> + }
> +
> + info.si_signo = killjid.sig;
> + info.si_errno = 0;
> + info.si_code = SI_USER;
> + info.si_pid = current->pid;
> + info.si_uid = current->uid;
> +
> + list_for_each(attached_entry, &job->attached) {
> + int err;
> + struct job_attach *attached;
> +
> + attached = list_entry(attached_entry, struct job_attach, entry);
> + err = send_sig_info(killjid.sig, &info,
> + attached->task);
> + if (err != 0) {
> + /*
> + * XXX - the "prime" process, or initiating process
> + * for the job may not be owned by the user. So,
> + * we would get an error in this case. However, we
> + * ignore the error for that specific process - it
> + * should exit when all the child processes exit. It
> + * should ignore all signals from the user.
> + *
> + */
> + if (attached->entry.prev != &job->attached) {
> + retcode = err;
> + }
> + }
> +
> + }
> +
> +cleanup_2locks_return:
> + JOB_RUNLOCK(&job->sem);
> +cleanup_1locks_return:
> + JOB_RUNLOCK(&job_table_sem);
> +cleanup_0locks_return:
> + killjid.r_val = retcode;
> +
> + DBG_PRINTEXIT(retcode);
> + if (copy_to_user(killjid_args, &killjid, sizeof(killjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return retcode;
> +}
> +
> +
> +/*
> + * job_sys_getjidcnt
> + *
> + * Retun the number of jobs currently on the system.
> + *
> + * returns 0 on success & it always succeeds.
> + */
> +static int
> +job_sys_getjidcnt(struct job_jidcnt *jidcnt_args)
> +{
> + struct job_jidcnt jidcnt;
> + DBG_PRINTINIT("job_sys_getjidcnt");
> +
> + DBG_PRINTENTRY();
> +
> + /* read lock might be overdoing it in this case */
> + JOB_RLOCK(&job_table_sem);
> + jidcnt.r_val = job_table_refcnt;
> + JOB_RUNLOCK(&job_table_sem);
> +
> + DBG_PRINTEXIT(0);
> +
> + if (copy_to_user(jidcnt_args, &jidcnt, sizeof(jidcnt))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + return 0;
> +}
> +
> +
> +/*
> + * job_sys_getjidlst
> + *
> + * Get the list of all jids currently on the system (limited by the number of
> + * jobs there are and the number you say you can accept.
> + */
> +static int
> +job_sys_getjidlst(struct job_jidlst *jidlst_args)
> +{
> + struct job_jidlst jidlst;
> + u64 *jid;
> + struct job_entry *job;
> + struct list_head *job_entry;
> + int i;
> + int count;
> + DBG_PRINTINIT("job_sys_getjidlst");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&jidlst, jidlst_args, sizeof(jidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> +
> + if (jidlst.r_val == 0) {
> + DBG_PRINTEXIT(0);
> + return 0;
> + }
> +
> + jid = (u64 *)kmalloc(sizeof(u64)*jidlst.r_val, GFP_KERNEL);
> + if (!jid) {
> + jidlst.r_val = 0;
> + DBG_PRINTEXIT(-ENOMEM);
> + if (copy_to_user(jidlst_args, &jidlst, sizeof(jidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return -ENOMEM;
> + }
> +
> +
> + count = 0;
> + JOB_RLOCK(&job_table_sem);
> + for (i = 0; i < HASH_SIZE && count < jidlst.r_val; i++) {
> + list_for_each(job_entry, &job_table[i]) {
> + job = list_entry(job_entry, struct job_entry, entry);
> + jid[count++] = job->jid;
> + if (count == jidlst.r_val) {
> + break;
> + }
> + }
> + }
> + JOB_RUNLOCK(&job_table_sem);
> +
> + DBG_PRINTEXIT(0);
> + jidlst.r_val = count;
> +
> + for (i = 0; i < count; i++) {
> + if (copy_to_user(jidlst.jid+i, &jid[i], sizeof(u64))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + }
> +
> + kfree(jid);
> +
> + if (copy_to_user(jidlst_args, &jidlst, sizeof(jidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return 0;
> +}
> +
> +
> +/*
> + * job_sys_getpidcnt
> + *
> + * Get the number of processes currently attached to a specific job.
> + *
> + * returns 0 on success, or negative errno value on failure.
> + */
> +static int
> +job_sys_getpidcnt(struct job_pidcnt *pidcnt_args)
> +{
> + struct job_pidcnt pidcnt;
> + struct job_entry *job;
> + int retcode = 0;
> + DBG_PRINTINIT("job_sys_getpidcnt");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&pidcnt, pidcnt_args, sizeof(pidcnt))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + pidcnt.r_val = 0;
> +
> + JOB_RLOCK(&job_table_sem);
> + job = job_getjob(pidcnt.jid);
> + if (!job) {
> + retcode = -ENODATA;
> + } else {
> + /* Read lock might be overdoing it for this case */
> + JOB_RLOCK(&job->sem);
> + pidcnt.r_val = job->refcnt;
> + JOB_RUNLOCK(&job->sem);
> + }
> + JOB_RUNLOCK(&job_table_sem);
> +
> + DBG_PRINTEXIT(retcode);
> +
> + if (copy_to_user(pidcnt_args, &pidcnt, sizeof(pidcnt))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return retcode;
> +}
> +
> +/*
> + * job_getpidlst
> + *
> + * Get the list of processes (pids) currently attached to the specified
> + * job. The number of processes provided is limited by the number the user
> + * specivies that they can accept (have memory for) and the number currently
> + * attached.
> + *
> + * returns 0 on success, negative errno value on failure.
> + */
> +static int
> +job_sys_getpidlst(struct job_pidlst *pidlst_args)
> +{
> + struct job_pidlst pidlst;
> + struct job_entry *job;
> + struct job_attach *attached;
> + struct list_head *attached_entry;
> + pid_t *pid;
> + int max;
> + int i;
> + DBG_PRINTINIT("job_sys_getpidlst");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&pidlst, pidlst_args, sizeof(pidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> +
> + if (pidlst.r_val == 0) {
> + DBG_PRINTEXIT(0);
> + return 0;
> + }
> +
> + max = pidlst.r_val;
> + pidlst.r_val = 0;
> + pid = (pid_t *)kmalloc(sizeof(pid_t)*max, GFP_KERNEL);
> + if (!pid) {
> + DBG_PRINTEXIT(-ENOMEM);
> + if (copy_to_user(pidlst_args, &pidlst, sizeof(pidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return -ENOMEM;
> + }
> +
> + JOB_RLOCK(&job_table_sem);
> +
> + job = job_getjob(pidlst.jid);
> + if (!job) {
> +
> + JOB_RUNLOCK(&job_table_sem);
> +
> + DBG_PRINTEXIT(-ENODATA);
> + if (copy_to_user(pidlst_args, &pidlst, sizeof(pidlst))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return -ENODATA;
> + } else {
> +
> + JOB_RLOCK(&job->sem);
> + JOB_RUNLOCK(&job_table_sem);
> +
> + i = 0;
> + list_for_each(attached_entry, &job->attached) {
> + if (i == max) {
> + break;
> + }
> + attached = list_entry(attached_entry, struct job_attach,
> + entry);
> + pid[i++] = attached->task->pid;
> + }
> + pidlst.r_val = i;
> +
> + JOB_RUNLOCK(&job->sem);
> + }
> +
> + for (i = 0; i < pidlst.r_val; i++) {
> + if (copy_to_user(pidlst.pid+i, &pid[i], sizeof(pid_t))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + }
> + kfree(pid);
> +
> + DBG_PRINTEXIT(0);
> + copy_to_user(pidlst_args, &pidlst, sizeof(pidlst));
> + return 0;
> +}
> +
> +
> +/*
> + * job_sys_getuser
> + *
> + * Get the uid of the user that owns the job.
> + *
> + * returns 0 on success, returns negative errno on failure.
> + */
> +static int
> +job_sys_getuser(struct job_user *user_args)
> +{
> + struct job_entry *job;
> + struct job_user user;
> + int retcode = 0;
> + DBG_PRINTINIT("job_sys_getuser");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&user, user_args, sizeof(user))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return(-EFAULT);
> + }
> +
> + user.r_user = 0;
> +
> + JOB_RLOCK(&job_table_sem);
> +
> + job = job_getjob(user.jid);
> + if (!job) {
> + retcode = -ENODATA;
> + } else {
> + JOB_RLOCK(&job->sem);
> + user.r_user = job->user;
> + JOB_RUNLOCK(&job->sem);
> + }
> +
> + JOB_RUNLOCK(&job_table_sem);
> +
> + if (copy_to_user(user_args, &user, sizeof(user))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + DBG_PRINTEXIT(retcode);
> + return retcode;
> +}
> +
> +
> +/*
> + * job_sys_getprimepid
> + *
> + * Get the primary process - the oldest process in the job.
> + *
> + * returns 0 on success, negative errno on failure.
> + */
> +static int
> +job_sys_getprimepid(struct job_primepid *primepid_args)
> +{
> + struct job_primepid primepid;
> + struct job_entry *job = NULL;
> + struct job_attach *attached = NULL;
> + int retcode = 0;
> + DBG_PRINTINIT("getprimepid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&primepid, primepid_args, sizeof(primepid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + primepid.r_pid = 0;
> +
> + JOB_RLOCK(&job_table_sem);
> +
> + job = job_getjob(primepid.jid);
> + if (!job) {
> + JOB_RUNLOCK(&job_table_sem);
> + /* Job not found, return INVALID VALUE */
> + DBG_PRINTEXIT(-ENODATA);
> + return -ENODATA;
> + }
> +
> + /*
> + * Job found, now look at first pid entry in the
> + * attached list.
> + */
> + JOB_RLOCK(&job->sem);
> + JOB_RUNLOCK(&job_table_sem);
> + if (list_empty(&job->attached)) {
> + retcode = -ESRCH;
> + primepid.r_pid = 0;
> + } else {
> + attached = list_entry(job->attached.next, struct job_attach, entry);
> + if (!attached->task) {
> + retcode = -ESRCH;
> + } else {
> + primepid.r_pid = attached->task->pid;
> + }
> + }
> + JOB_RUNLOCK(&job->sem);
> +
> + if (copy_to_user(primepid_args, &primepid, sizeof(primepid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + DBG_PRINTEXIT(retcode);
> + return retcode;
> +}
> +
> +
> +/*
> + * job_sys_sethid
> + *
> + * This function is used to set the host ID segment for the job IDs (jid).
> + * If this does not get set, then the jids upper 32 bits will be set to
> + * 0 and the jid cannot be used reliably in a cluster environment.
> + *
> + * returns -errno value on fail, 0 on success
> + */
> +static int
> +job_sys_sethid(struct job_sethid *sethid_args)
> +{
> + struct job_sethid sethid;
> + int errcode = 0;
> + DBG_PRINTINIT("job_sys_sethid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&sethid, sethid_args, sizeof(sethid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + if (!capable(CAP_SYS_RESOURCE)) {
> + errcode = -EPERM;
> + sethid.r_hid = 0;
> + goto cleanup_return;
> + }
> +
> + /*
> + * Set job_table_sem, so no jobs can be deleted while doing
> + * this operation.
> + */
> + JOB_WLOCK(&job_table_sem);
> +
> + sethid.r_hid = jid_hid = sethid.hid;
> +
> + JOB_WUNLOCK(&job_table_sem);
> +
> +cleanup_return:
> + DBG_PRINTEXIT(errcode);
> + if (copy_to_user(sethid_args, &sethid, sizeof(sethid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return errcode;
> +}
> +
> +
> +/*
> + * job_sys_detachjid
> + *
> + * This function is detach all the processes from a job, but allows the
> + * processes to continue running. You need CAP_SYS_RESOURCE capability
> + * for this to succeed. Since all processes will be detached, the job will
> + * exit.
> + *
> + * returns -errno value on fail, 0 on success
> + */
> +static int
> +job_sys_detachjid(struct job_detachjid *detachjid_args)
> +{
> + struct job_detachjid detachjid;
> + struct job_entry *job;
> + struct list_head *entry;
> + int count;
> + int errcode = 0;
> + struct task_struct *task;
> + struct pagg *pagg;
> +
> + DBG_PRINTINIT("job_sys_detachjid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&detachjid, detachjid_args, sizeof(detachjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + detachjid.r_val = 0;
> +
> + if (!capable(CAP_SYS_RESOURCE)) {
> + errcode = -EPERM;
> + goto cleanup_return;
> + }
> +
> + /*
> + * Set job_table_sem, so no jobs can be deleted while doing
> + * this operation.
> + */
> + JOB_WLOCK(&job_table_sem);
> +
> + job = job_getjob(detachjid.jid);
> +
> + if (job) {
> +
> + JOB_WLOCK(&job->sem);
> +
> + /* Mark job as ZOMBIE so no new processes can attach to it */
> + job->state = ZOMBIE;
> +
> + count = job->refcnt;
> +
> + /* Okay, no new processes can attach to the job. We can
> + * release the locks on the job_table and job since the only
> + * way for the job to change now is for tasks to detach and
> + * the job to be removed. And this is what we want to happen
> + */
> + JOB_WUNLOCK(&job_table_sem);
> + JOB_WUNLOCK(&job->sem);
> +
> +
> + /* Walk through list of attached tasks and unset the
> + * pagg entries.
> + *
> + * We don't test with list_empty because that actually means NO tasks
> + * left rather than one task. If we used !list_empty or list_for_each,
> + * we could reference memory freed by the pagg hook detach function
> + * (job_detach).
> + *
> + * We know there is only one task left when job->attached.next and
> + * job->attached.prev both point to the same place.
> + */
> + while (job->attached.next != job->attached.prev) {
> + entry = job->attached.next;
> +
> + task = (list_entry(entry, struct job_attach, entry))->task;
> + pagg = (list_entry(entry, struct job_attach, entry))->pagg;
> +
> + down_write(&task->pagg_sem); /* write lock pagg list */
> + pagg->hook->detach(task, pagg);
> + pagg_free(pagg);
> + up_write(&task->pagg_sem); /* write unlock pagg list */
> +
> + }
> + /* At this point, there is only one task left */
> +
> + entry = job->attached.next;
> +
> + task = (list_entry(entry, struct job_attach, entry))->task;
> + pagg = (list_entry(entry, struct job_attach, entry))->pagg;
> +
> + down_write(&task->pagg_sem); /* write lock pagg list */
> + pagg->hook->detach(task, pagg);
> + pagg_free(pagg);
> + up_write(&task->pagg_sem); /* write unlock pagg list */
> +
> + detachjid.r_val = count;
> +
> + } else {
> + errcode = -ENODATA;
> + JOB_WUNLOCK(&job_table_sem);
> + }
> +
> +cleanup_return:
> + DBG_PRINTEXIT(errcode);
> + if (copy_to_user(detachjid_args, &detachjid, sizeof(detachjid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return errcode;
> +}
> +
> +
> +/*
> + * job_sys_detachpid
> + *
> + * This function is detach a process from the job it is attached too,
> + * but allows the processes to continue running. You need
> + * CAP_SYS_RESOURCE capability for this to succeed.
> + *
> + * returns -errno value on fail, 0 on success
> + */
> +static int
> +job_sys_detachpid(struct job_detachpid *detachpid_args)
> +{
> + struct job_detachpid detachpid;
> + struct task_struct *task;
> + struct pagg *pagg;
> + int errcode = 0;
> + DBG_PRINTINIT("job_sys_detachpid");
> +
> + DBG_PRINTENTRY();
> +
> + if (copy_from_user(&detachpid, detachpid_args, sizeof(detachpid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> +
> + detachpid.r_jid = 0;
> +
> + if (!capable(CAP_SYS_RESOURCE)) {
> + errcode = -EPERM;
> + goto cleanup_return;
> + }
> +
> + /* Lock the task list while we find a specific task */
> + read_lock(&tasklist_lock);
> + task = find_task_by_pid(detachpid.pid);
> + if (!task) {
> + errcode = -ESRCH;
> + /* We need to unlock the tasklist here too or the lock is held forever */
> + read_unlock(&tasklist_lock);
> + goto cleanup_return;
> + }
> +
> + /* We have a valid task now */
> + get_task_struct(task); /* Ensure the task doesn't vanish on us */
> + read_unlock(&tasklist_lock); /* Unlock the tasklist */
> + down_write(&task->pagg_sem); /* write lock pagg list */
> +
> + pagg = pagg_get(task, pagg_hook.name);
> + if (pagg) {
> + detachpid.r_jid = ((struct job_attach *)pagg->data)->job->jid;
> + pagg->hook->detach(task, pagg);
> + pagg_free(pagg);
> + } else {
> + errcode = -ENODATA;
> + }
> + put_task_struct(task); /* Done accessing the task */
> + up_write(&task->pagg_sem); /* write unlock pagg list */
> +
> +cleanup_return:
> + DBG_PRINTEXIT(errcode);
> + if (copy_to_user(detachpid_args, &detachpid, sizeof(detachpid))) {
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT;
> + }
> + return errcode;
> +}
> +
> +
> +/*
> + * job_register_acct
> + *
> + * This function is used by modules that are registering to provide job
> + * accounting services.
> + *
> + * returns -errno value on fail, 0 on success.
> + */
> +int
> +job_register_acct(struct job_acctmod *am)
> +{
> + DBG_PRINTINIT("job_register_acct");
> +
> + DBG_PRINTENTRY();
> +
> + if (!am) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL; /* error, invalid value */
> + }
> + if (am->type < 0 || am->type > (JOB_ACCT_COUNT-1)) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL; /* error, invalid value */
> + }
> +
> + JOB_WLOCK(&acct_list_sem);
> + if (acct_list[am->type] != NULL) {
> + JOB_WUNLOCK(&acct_list_sem);
> + DBG_PRINTEXIT(-EBUSY);
> + return -EBUSY; /* error, duplicate entry */
> + }
> +
> + acct_list[am->type] = am;
> + JOB_WUNLOCK(&acct_list_sem);
> + DBG_PRINTEXIT(0);
> + return 0;
> +}
> +
> +
> +/*
> + * job_unregister_acct
> + *
> + * This is used by accounting modules to unregister with the job module as
> + * subscribers for job accounting information.
> + *
> + * Returns -errno on failure and 0 on success.
> + */
> +int
> +job_unregister_acct(struct job_acctmod *am)
> +{
> + DBG_PRINTINIT("job_unregister_acct");
> +
> + DBG_PRINTENTRY();
> +
> + if (!am) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL; /* error, invalid value */
> + }
> + if (am->type < 0 || am->type > (JOB_ACCT_COUNT-1)) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL; /* error, invalid value */
> + }
> +
> + JOB_WLOCK(&acct_list_sem);
> + if (acct_list[am->type] != am) {
> + JOB_WUNLOCK(&acct_list_sem);
> + DBG_PRINTEXIT(-EFAULT);
> + return -EFAULT; /* error, not matching entry */
> + }
> +
> + acct_list[am->type] = NULL;
> + JOB_WUNLOCK(&acct_list_sem);
> + DBG_PRINTEXIT(0);
> + return 0;
> +}
> +
> +/*
> + * job_getjid
> + *
> + * This function will return the Job ID for the given task. If
> + * the task is not attached to a job, then 0 is returned.
> + *
> + */
> +u64 job_getjid(struct task_struct *task)
> +{
> + struct pagg *pagg = NULL;
> + struct job_entry *job = NULL;
> + u64 jid = 0;
> + DBG_PRINTINIT("job_getjid");
> +
> + DBG_PRINTENTRY();
> +
> + down_read(&task->pagg_sem); /* lock pagg list */
> + pagg = pagg_get(task, pagg_hook.name);
> + if (pagg) {
> + job = ((struct job_attach *)pagg->data)->job;
> + JOB_RLOCK(&job->sem);
> + jid = job->jid;
> + JOB_RUNLOCK(&job->sem);
> + }
> + up_read(&task->pagg_sem);
> +
> + DBG_PRINTEXIT((int)jid);
> + return jid;
> +}
> +
> +
> +/*
> + * job_getacct
> + *
> + * This function is used by accounting subscribers to get accounting
> + * information about a job.
> + *
> + * The caller must supply the Job ID (jid) that specifies the job. The
> + * "type" argument indicates the type of accounting data to be returned.
> + * The data will be returned in the memory accessed via the data pointer
> + * argument. The data pointer is void so that this function interface
> + * can handle different types of accounting data.
> + */
> +int job_getacct(u64 jid, int type, void *data)
> +{
> + struct job_entry *job;
> + DBG_PRINTINIT("job_getacct");
> +
> + DBG_PRINTENTRY();
> +
> + if (!data) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + }
> +
> + if (!jid) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + }
> +
> + JOB_RLOCK(&job_table_sem);
> + job = job_getjob(jid);
> + if (!job) {
> + JOB_RUNLOCK(&job_table_sem);
> + DBG_PRINTEXIT(-ENODATA);
> + return -ENODATA;
> + }
> +
> + JOB_RLOCK(&job->sem);
> + JOB_RUNLOCK(&job_table_sem);
> +
> + switch (type) {
> +#if defined(CONFIG_CSA) || defined(CONFIG_CSA_MODULE)
> + case JOB_ACCT_CSA:
> + {
> + struct job_csa *csa = (struct job_csa *)data;
> +
> + csa->job_id = job->jid;
> + csa->job_uid = job->user;
> + csa->job_start = job->start;
> + csa->job_corehimem = job->csa.corehimem;
> + csa->job_virthimem = job->csa.virthimem;
> + csa->job_acctfile = job->csa.acctfile;
> + break;
> + }
> +#endif
> + default:
> + JOB_RUNLOCK(&job->sem);
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + break;
> + }
> + JOB_RUNLOCK(&job->sem);
> + DBG_PRINTEXIT(0);
> + return 0;
> +}
> +
> +/*
> + * job_setacct
> + *
> + * This function is used by accounting subscribers to set specific
> + * accounting information in the job (so that the job remembers it
> + * in relation to a specific job).
> + *
> + * The job is identified by the jid argument. The type indicates the
> + * type of accounting the information is associated with. The subfield
> + * is a bitmask that indicates exactly what subfields are to be changed.
> + * The data that is used to set the values is supplied by the data pointer.
> + * The data pointer is a void type so that the interface can be used for
> + * different types of accounting information.
> + */
> +int job_setacct(u64 jid, int type, int subfield, void *data)
> +{
> + struct job_entry *job;
> + DBG_PRINTINIT("job_setacct");
> +
> + DBG_PRINTENTRY();
> +
> + if (!data) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + }
> +
> + if (!jid) {
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + }
> +
> + JOB_RLOCK(&job_table_sem);
> + job = job_getjob(jid);
> + if (!job) {
> + JOB_RUNLOCK(&job_table_sem);
> + DBG_PRINTEXIT(-ENODATA);
> + return -ENODATA;
> + }
> +
> + JOB_RLOCK(&job->sem);
> + JOB_RUNLOCK(&job_table_sem);
> +
> + switch (type) {
> +#if defined(CONFIG_CSA) || defined(CONFIG_CSA_MODULE)
> + case JOB_ACCT_CSA:
> + {
> + struct job_csa *csa = (struct job_csa *)data;
> +
> + if (subfield & JOB_CSA_ACCTFILE) {
> + job->csa.acctfile = csa->job_acctfile;
> + }
> + break;
> + }
> +#endif
> + default:
> + JOB_RUNLOCK(&job->sem);
> + DBG_PRINTEXIT(-EINVAL);
> + return -EINVAL;
> + break;
> + }
> + JOB_RUNLOCK(&job->sem);
> + DBG_PRINTEXIT(0);
> + return 0;
> +}
> +
> +
> +
> +/*
> + * job_syscall
> + *
> + * Function to handle job syscall requests.
> + *
> + * Returns 0 on success and -(ERRNO VALUE) upon failure.
> + */
> +int
> +job_syscall(unsigned int request, unsigned long data)
> +{
> + int rc=0;
> +
> + DBG_PRINTINIT("job_syscall");
> +
> + DBG_PRINTENTRY();
> +
> + switch (request) {
> + case JOB_CREATE:
> + rc = job_sys_create((struct job_create *)data);
> + break;
> + case JOB_ATTACH:
> + case JOB_DETACH:
> + /* RESERVED */
> + rc = -EBADRQC;
> + break;
> + case JOB_GETJID:
> + rc = job_sys_getjid((struct job_getjid *)data);
> + break;
> + case JOB_WAITJID:
> + rc = job_sys_waitjid((struct job_waitjid *)data);
> + break;
> + case JOB_KILLJID:
> + rc = job_sys_killjid((struct job_killjid *)data);
> + break;
> + case JOB_GETJIDCNT:
> + rc = job_sys_getjidcnt((struct job_jidcnt *)data);
> + break;
> + case JOB_GETJIDLST:
> + rc = job_sys_getjidlst((struct job_jidlst *)data);
> + break;
> + case JOB_GETPIDCNT:
> + rc = job_sys_getpidcnt((struct job_pidcnt *)data);
> + break;
> + case JOB_GETPIDLST:
> + rc = job_sys_getpidlst((struct job_pidlst *)data);
> + break;
> + case JOB_GETUSER:
> + rc = job_sys_getuser((struct job_user *)data);
> + break;
> + case JOB_GETPRIMEPID:
> + rc = job_sys_getprimepid((struct job_primepid *)data);
> + break;
> + case JOB_SETHID:
> + rc = job_sys_sethid((struct job_sethid *)data);
> + break;
> + case JOB_DETACHJID:
> + rc = job_sys_detachjid((struct job_detachjid *)data);
> + break;
> + case JOB_DETACHPID:
> + rc = job_sys_detachpid((struct job_detachpid *)data);
> + break;
> + case JOB_SETJLIMIT:
> + case JOB_GETJLIMIT:
> + case JOB_GETJUSAGE:
> + case JOB_FREE:
> + default:
> + rc = -EBADRQC;
> + break;
> + }
> +
> + DBG_PRINTEXIT(rc);
> + return rc;
> +}
> +
> +
> +/*
> + * job_ioctl
> + *
> + * Function to handle job ioctl call requests.
> + *
> + * Returns 0 on success and -(ERRNO VALUE) upon failure.
> + */
> +int
> +job_ioctl(struct inode *inode, struct file *file, unsigned int request,
> + unsigned long data)
> +{
> + return job_syscall(request, data);
> +}
> +
> +
> +/*
> + * init_module
> + *
> + * This function is called when a module is inserted into a kernel. This
> + * function allocates any necessary structures and sets initial values for
> + * module data.
> + *
> + * If the function succeeds, then 0 is returned. On failure, -1 is returned.
> + */
> +static int __init
> +init_job(void)
> +{
> + int i,rc;
> +
> +
> + /* Initialize the job table chains */
> + for (i = 0; i < HASH_SIZE; i++) {
> + INIT_LIST_HEAD(&job_table[i]);
> + }
> +
> + /* Initialize the list for accounting subscribers */
> + for (i = 0; i < JOB_ACCT_COUNT; i++) {
> + acct_list[i] = NULL;
> + }
> +
> + /* Get hostID string and fill in jid_template hostID segment */
> + if (hid) {
> + jid_hid = (int)simple_strtoul(hid, &hid, 16);
> + } else {
> + jid_hid = 0;
> + }
> +
> + rc = pagg_hook_register(&pagg_hook);
> + if (rc < 0) {
> + return -1;
> + }
> +
> + /* Setup our /proc entry file */
> + job_proc_entry = create_proc_entry(JOB_PROC_ENTRY,
> + S_IFREG | S_IRUGO, &proc_root);
> +
> + if (!job_proc_entry) {
> + pagg_hook_unregister(&pagg_hook);
> + return -1;
> + }
> +
> + job_proc_entry->proc_fops = &job_file_ops;
> + job_proc_entry->proc_iops = NULL;
> +
> +
> + return 0;
> +}
> +module_init(init_job);
> +
> +/*
> + * cleanup_module
> + *
> + * This function is called to cleanup after a module when it is removed.
> + * All memory allocated for this module will be freed.
> + *
> + * This function does not take any inputs or produce and output.
> + */
> +static void __exit
> +cleanup_job(void)
> +{
> + remove_proc_entry(JOB_PROC_ENTRY, &proc_root);
> + pagg_hook_unregister(&pagg_hook);
> + return;
> +}
> +module_exit(cleanup_job);
> +
> +EXPORT_SYMBOL(job_register_acct);
> +EXPORT_SYMBOL(job_unregister_acct);
> +EXPORT_SYMBOL(job_getjid);
> +EXPORT_SYMBOL(job_getacct);
> +EXPORT_SYMBOL(job_setacct);
> Index: linux/kernel/Makefile
> ===================================================================
> --- linux.orig/kernel/Makefile 2004-08-16 10:41:23.000000000 -0500
> +++ linux/kernel/Makefile 2004-08-16 10:42:38.000000000 -0500
> @@ -19,6 +19,7 @@
> obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
> obj-$(CONFIG_COMPAT) += compat.o
> obj-$(CONFIG_PAGG) += pagg.o
> +obj-$(CONFIG_PAGG_JOB) += job.o
> obj-$(CONFIG_IKCONFIG) += configs.o
> obj-$(CONFIG_IKCONFIG_PROC) += configs.o
> obj-$(CONFIG_STOP_MACHINE) += stop_machine.o
* John Hesterberg ([email protected]) wrote:
> The current job /proc ioctl interface is really a fake-syscall interface.
> We only did that so that our product didn't have to lock into a syscall
> number that would eventually be used by something else.
>
> The easiest thing for us would probably be to turn it back into a system
> call, if that would be acceptable for inclusion into the kernel. We're
> open to other job interfaces, such as a real /proc character interface,
> or a new virtual filesystem, or a device driver using ioctls.
But that system call would still be a single mutliplexor for many calls, right?
Not ideal. Have you tried to map to an fs? It's nice and contained, and may be a
simple mapping. Question comes with CKRM, and if they'll have similar needs. If
that's the case, first class syscalls (no multiplexor) may be way to go.
thanks,
-chris
--
Linux Security Modules http://lsm.immunix.org http://lsm.bkbits.net
* Limin Gu ([email protected]) wrote:
> I don't have much experience on implementing virtual filesystem,
> but I am willing to try it if that is the right interface for job.
> However, I am not sure how to map all current job ioctls to a
> nice and simple filesystem, at the same time I would like to keep
> the user library interface the same so our applications will not
> break.
>
> Would you mind giving me some help on the job ioctls and fs
> mapping? Thanks in advance!
Sure, I'll give you a hand.
-chris
>
> * John Hesterberg ([email protected]) wrote:
> > The current job /proc ioctl interface is really a fake-syscall interface.
> > We only did that so that our product didn't have to lock into a syscall
> > number that would eventually be used by something else.
> >
> > The easiest thing for us would probably be to turn it back into a system
> > call, if that would be acceptable for inclusion into the kernel. We're
> > open to other job interfaces, such as a real /proc character interface,
> > or a new virtual filesystem, or a device driver using ioctls.
>
> But that system call would still be a single mutliplexor for many calls, right?
> Not ideal. Have you tried to map to an fs? It's nice and contained, and may be a
> simple mapping. Question comes with CKRM, and if they'll have similar needs. If
> that's the case, first class syscalls (no multiplexor) may be way to go.
Hi Chris,
I don't have much experience on implementing virtual filesystem,
but I am willing to try it if that is the right interface for job.
However, I am not sure how to map all current job ioctls to a
nice and simple filesystem, at the same time I would like to keep
the user library interface the same so our applications will not
break.
Would you mind giving me some help on the job ioctls and fs
mapping? Thanks in advance!
Limin
>
> thanks,
> -chris
> --
> Linux Security Modules http://lsm.immunix.org http://lsm.bkbits.net
>
Chris Wright <[email protected]> wrote:
>
> * John Hesterberg ([email protected]) wrote:
> > The current job /proc ioctl interface is really a fake-syscall interface.
> > We only did that so that our product didn't have to lock into a syscall
> > number that would eventually be used by something else.
> >
> > The easiest thing for us would probably be to turn it back into a system
> > call, if that would be acceptable for inclusion into the kernel. We're
> > open to other job interfaces, such as a real /proc character interface,
> > or a new virtual filesystem, or a device driver using ioctls.
>
> But that system call would still be a single mutliplexor for many calls, right?
Either that, or 19 separate syscalls...
> Not ideal. Have you tried to map to an fs?
That's worth investigation.
* Andrew Morton ([email protected]) wrote:
> Chris Wright <[email protected]> wrote:
> > But that system call would still be a single mutliplexor for many calls, right?
>
> Either that, or 19 separate syscalls...
Heh, you snipped out the part where I (obtusely) said that ;-)
> > Not ideal. Have you tried to map to an fs?
>
> That's worth investigation.
Limin and I are checking it out.
thanks,
-chris