mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-25 04:50:57 +07:00
d74beb9f33
This patch avoids arithmetic on 'signed' types that are slower than 'unsigned'. This saves space and cpu cycles. size of kernel/sys.o before the patch (gcc-3.4.5) text data bss dec hex filename 10924 252 4 11180 2bac kernel/sys.o size of kernel/sys.o after the patch text data bss dec hex filename 10903 252 4 11159 2b97 kernel/sys.o I noticed that gcc-4.1.0 (from Fedora Core 5) even uses idiv instruction for (a+b)/2 if a and b are signed. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1895 lines
44 KiB
C
1895 lines
44 KiB
C
/*
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||
* linux/kernel/sys.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*/
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#include <linux/config.h>
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#include <linux/module.h>
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#include <linux/mm.h>
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#include <linux/utsname.h>
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#include <linux/mman.h>
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#include <linux/smp_lock.h>
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#include <linux/notifier.h>
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#include <linux/reboot.h>
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#include <linux/prctl.h>
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#include <linux/init.h>
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#include <linux/highuid.h>
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#include <linux/fs.h>
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#include <linux/kernel.h>
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#include <linux/kexec.h>
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#include <linux/workqueue.h>
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#include <linux/capability.h>
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#include <linux/device.h>
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#include <linux/key.h>
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#include <linux/times.h>
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#include <linux/posix-timers.h>
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#include <linux/security.h>
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#include <linux/dcookies.h>
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#include <linux/suspend.h>
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#include <linux/tty.h>
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#include <linux/signal.h>
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#include <linux/cn_proc.h>
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#include <linux/compat.h>
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#include <linux/syscalls.h>
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#include <linux/kprobes.h>
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#include <asm/uaccess.h>
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#include <asm/io.h>
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#include <asm/unistd.h>
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#ifndef SET_UNALIGN_CTL
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# define SET_UNALIGN_CTL(a,b) (-EINVAL)
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#endif
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#ifndef GET_UNALIGN_CTL
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# define GET_UNALIGN_CTL(a,b) (-EINVAL)
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#endif
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#ifndef SET_FPEMU_CTL
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# define SET_FPEMU_CTL(a,b) (-EINVAL)
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#endif
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#ifndef GET_FPEMU_CTL
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# define GET_FPEMU_CTL(a,b) (-EINVAL)
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#endif
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#ifndef SET_FPEXC_CTL
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# define SET_FPEXC_CTL(a,b) (-EINVAL)
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#endif
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#ifndef GET_FPEXC_CTL
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# define GET_FPEXC_CTL(a,b) (-EINVAL)
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#endif
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/*
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* this is where the system-wide overflow UID and GID are defined, for
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* architectures that now have 32-bit UID/GID but didn't in the past
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*/
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int overflowuid = DEFAULT_OVERFLOWUID;
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int overflowgid = DEFAULT_OVERFLOWGID;
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#ifdef CONFIG_UID16
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EXPORT_SYMBOL(overflowuid);
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EXPORT_SYMBOL(overflowgid);
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#endif
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/*
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* the same as above, but for filesystems which can only store a 16-bit
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* UID and GID. as such, this is needed on all architectures
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*/
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int fs_overflowuid = DEFAULT_FS_OVERFLOWUID;
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int fs_overflowgid = DEFAULT_FS_OVERFLOWUID;
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EXPORT_SYMBOL(fs_overflowuid);
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EXPORT_SYMBOL(fs_overflowgid);
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/*
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* this indicates whether you can reboot with ctrl-alt-del: the default is yes
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*/
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int C_A_D = 1;
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int cad_pid = 1;
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/*
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* Notifier list for kernel code which wants to be called
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* at shutdown. This is used to stop any idling DMA operations
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* and the like.
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*/
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static struct notifier_block *reboot_notifier_list;
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static DEFINE_RWLOCK(notifier_lock);
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/**
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* notifier_chain_register - Add notifier to a notifier chain
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* @list: Pointer to root list pointer
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* @n: New entry in notifier chain
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*
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* Adds a notifier to a notifier chain.
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*
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* Currently always returns zero.
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*/
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int notifier_chain_register(struct notifier_block **list, struct notifier_block *n)
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{
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write_lock(¬ifier_lock);
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while(*list)
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{
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if(n->priority > (*list)->priority)
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break;
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list= &((*list)->next);
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}
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n->next = *list;
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*list=n;
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write_unlock(¬ifier_lock);
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return 0;
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}
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EXPORT_SYMBOL(notifier_chain_register);
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/**
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* notifier_chain_unregister - Remove notifier from a notifier chain
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* @nl: Pointer to root list pointer
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* @n: New entry in notifier chain
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*
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* Removes a notifier from a notifier chain.
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*
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* Returns zero on success, or %-ENOENT on failure.
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*/
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int notifier_chain_unregister(struct notifier_block **nl, struct notifier_block *n)
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{
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write_lock(¬ifier_lock);
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while((*nl)!=NULL)
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{
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if((*nl)==n)
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{
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*nl=n->next;
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write_unlock(¬ifier_lock);
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return 0;
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}
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nl=&((*nl)->next);
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}
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write_unlock(¬ifier_lock);
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return -ENOENT;
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}
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EXPORT_SYMBOL(notifier_chain_unregister);
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/**
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* notifier_call_chain - Call functions in a notifier chain
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* @n: Pointer to root pointer of notifier chain
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* @val: Value passed unmodified to notifier function
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* @v: Pointer passed unmodified to notifier function
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*
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* Calls each function in a notifier chain in turn.
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*
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* If the return value of the notifier can be and'd
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* with %NOTIFY_STOP_MASK, then notifier_call_chain
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* will return immediately, with the return value of
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* the notifier function which halted execution.
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* Otherwise, the return value is the return value
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* of the last notifier function called.
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*/
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int __kprobes notifier_call_chain(struct notifier_block **n, unsigned long val, void *v)
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{
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int ret=NOTIFY_DONE;
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struct notifier_block *nb = *n;
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while(nb)
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{
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ret=nb->notifier_call(nb,val,v);
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if(ret&NOTIFY_STOP_MASK)
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{
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return ret;
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}
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nb=nb->next;
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}
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return ret;
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}
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EXPORT_SYMBOL(notifier_call_chain);
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/**
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* register_reboot_notifier - Register function to be called at reboot time
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* @nb: Info about notifier function to be called
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*
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* Registers a function with the list of functions
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* to be called at reboot time.
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*
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* Currently always returns zero, as notifier_chain_register
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* always returns zero.
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*/
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int register_reboot_notifier(struct notifier_block * nb)
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{
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return notifier_chain_register(&reboot_notifier_list, nb);
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}
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EXPORT_SYMBOL(register_reboot_notifier);
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/**
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* unregister_reboot_notifier - Unregister previously registered reboot notifier
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* @nb: Hook to be unregistered
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*
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* Unregisters a previously registered reboot
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* notifier function.
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*
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* Returns zero on success, or %-ENOENT on failure.
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*/
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int unregister_reboot_notifier(struct notifier_block * nb)
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{
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return notifier_chain_unregister(&reboot_notifier_list, nb);
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}
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EXPORT_SYMBOL(unregister_reboot_notifier);
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static int set_one_prio(struct task_struct *p, int niceval, int error)
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{
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int no_nice;
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if (p->uid != current->euid &&
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p->euid != current->euid && !capable(CAP_SYS_NICE)) {
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error = -EPERM;
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goto out;
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}
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if (niceval < task_nice(p) && !can_nice(p, niceval)) {
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error = -EACCES;
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goto out;
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}
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no_nice = security_task_setnice(p, niceval);
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if (no_nice) {
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error = no_nice;
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goto out;
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}
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if (error == -ESRCH)
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error = 0;
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set_user_nice(p, niceval);
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out:
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return error;
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}
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asmlinkage long sys_setpriority(int which, int who, int niceval)
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{
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struct task_struct *g, *p;
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struct user_struct *user;
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int error = -EINVAL;
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if (which > 2 || which < 0)
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goto out;
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/* normalize: avoid signed division (rounding problems) */
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error = -ESRCH;
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if (niceval < -20)
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niceval = -20;
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if (niceval > 19)
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niceval = 19;
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read_lock(&tasklist_lock);
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switch (which) {
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case PRIO_PROCESS:
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if (!who)
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who = current->pid;
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p = find_task_by_pid(who);
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if (p)
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error = set_one_prio(p, niceval, error);
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break;
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case PRIO_PGRP:
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if (!who)
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who = process_group(current);
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do_each_task_pid(who, PIDTYPE_PGID, p) {
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error = set_one_prio(p, niceval, error);
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} while_each_task_pid(who, PIDTYPE_PGID, p);
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break;
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case PRIO_USER:
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user = current->user;
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if (!who)
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who = current->uid;
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else
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if ((who != current->uid) && !(user = find_user(who)))
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goto out_unlock; /* No processes for this user */
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do_each_thread(g, p)
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if (p->uid == who)
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error = set_one_prio(p, niceval, error);
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while_each_thread(g, p);
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if (who != current->uid)
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free_uid(user); /* For find_user() */
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break;
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}
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out_unlock:
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read_unlock(&tasklist_lock);
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out:
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return error;
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}
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/*
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* Ugh. To avoid negative return values, "getpriority()" will
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* not return the normal nice-value, but a negated value that
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* has been offset by 20 (ie it returns 40..1 instead of -20..19)
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* to stay compatible.
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*/
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asmlinkage long sys_getpriority(int which, int who)
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{
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struct task_struct *g, *p;
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struct user_struct *user;
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long niceval, retval = -ESRCH;
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if (which > 2 || which < 0)
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return -EINVAL;
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read_lock(&tasklist_lock);
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switch (which) {
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case PRIO_PROCESS:
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if (!who)
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who = current->pid;
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p = find_task_by_pid(who);
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if (p) {
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niceval = 20 - task_nice(p);
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if (niceval > retval)
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retval = niceval;
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}
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break;
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case PRIO_PGRP:
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if (!who)
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who = process_group(current);
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do_each_task_pid(who, PIDTYPE_PGID, p) {
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niceval = 20 - task_nice(p);
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if (niceval > retval)
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retval = niceval;
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} while_each_task_pid(who, PIDTYPE_PGID, p);
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break;
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case PRIO_USER:
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user = current->user;
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if (!who)
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who = current->uid;
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else
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if ((who != current->uid) && !(user = find_user(who)))
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goto out_unlock; /* No processes for this user */
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do_each_thread(g, p)
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if (p->uid == who) {
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niceval = 20 - task_nice(p);
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if (niceval > retval)
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retval = niceval;
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}
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while_each_thread(g, p);
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if (who != current->uid)
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free_uid(user); /* for find_user() */
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break;
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}
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out_unlock:
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read_unlock(&tasklist_lock);
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return retval;
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}
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/**
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* emergency_restart - reboot the system
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*
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* Without shutting down any hardware or taking any locks
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* reboot the system. This is called when we know we are in
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* trouble so this is our best effort to reboot. This is
|
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* safe to call in interrupt context.
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*/
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void emergency_restart(void)
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{
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machine_emergency_restart();
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}
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EXPORT_SYMBOL_GPL(emergency_restart);
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void kernel_restart_prepare(char *cmd)
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{
|
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notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
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system_state = SYSTEM_RESTART;
|
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device_shutdown();
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}
|
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|
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/**
|
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* kernel_restart - reboot the system
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* @cmd: pointer to buffer containing command to execute for restart
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* or %NULL
|
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*
|
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* Shutdown everything and perform a clean reboot.
|
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* This is not safe to call in interrupt context.
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*/
|
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void kernel_restart(char *cmd)
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{
|
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kernel_restart_prepare(cmd);
|
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if (!cmd) {
|
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printk(KERN_EMERG "Restarting system.\n");
|
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} else {
|
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printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd);
|
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}
|
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printk(".\n");
|
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machine_restart(cmd);
|
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}
|
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EXPORT_SYMBOL_GPL(kernel_restart);
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|
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/**
|
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* kernel_kexec - reboot the system
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*
|
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* Move into place and start executing a preloaded standalone
|
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* executable. If nothing was preloaded return an error.
|
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*/
|
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void kernel_kexec(void)
|
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{
|
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#ifdef CONFIG_KEXEC
|
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struct kimage *image;
|
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image = xchg(&kexec_image, NULL);
|
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if (!image) {
|
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return;
|
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}
|
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kernel_restart_prepare(NULL);
|
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printk(KERN_EMERG "Starting new kernel\n");
|
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machine_shutdown();
|
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machine_kexec(image);
|
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#endif
|
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}
|
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EXPORT_SYMBOL_GPL(kernel_kexec);
|
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|
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void kernel_shutdown_prepare(enum system_states state)
|
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{
|
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notifier_call_chain(&reboot_notifier_list,
|
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(state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL);
|
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system_state = state;
|
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device_shutdown();
|
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}
|
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/**
|
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* kernel_halt - halt the system
|
||
*
|
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* Shutdown everything and perform a clean system halt.
|
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*/
|
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void kernel_halt(void)
|
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{
|
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kernel_shutdown_prepare(SYSTEM_HALT);
|
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printk(KERN_EMERG "System halted.\n");
|
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machine_halt();
|
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}
|
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|
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EXPORT_SYMBOL_GPL(kernel_halt);
|
||
|
||
/**
|
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* kernel_power_off - power_off the system
|
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*
|
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* Shutdown everything and perform a clean system power_off.
|
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*/
|
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void kernel_power_off(void)
|
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{
|
||
kernel_shutdown_prepare(SYSTEM_POWER_OFF);
|
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printk(KERN_EMERG "Power down.\n");
|
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machine_power_off();
|
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}
|
||
EXPORT_SYMBOL_GPL(kernel_power_off);
|
||
/*
|
||
* Reboot system call: for obvious reasons only root may call it,
|
||
* and even root needs to set up some magic numbers in the registers
|
||
* so that some mistake won't make this reboot the whole machine.
|
||
* You can also set the meaning of the ctrl-alt-del-key here.
|
||
*
|
||
* reboot doesn't sync: do that yourself before calling this.
|
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*/
|
||
asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user * arg)
|
||
{
|
||
char buffer[256];
|
||
|
||
/* We only trust the superuser with rebooting the system. */
|
||
if (!capable(CAP_SYS_BOOT))
|
||
return -EPERM;
|
||
|
||
/* For safety, we require "magic" arguments. */
|
||
if (magic1 != LINUX_REBOOT_MAGIC1 ||
|
||
(magic2 != LINUX_REBOOT_MAGIC2 &&
|
||
magic2 != LINUX_REBOOT_MAGIC2A &&
|
||
magic2 != LINUX_REBOOT_MAGIC2B &&
|
||
magic2 != LINUX_REBOOT_MAGIC2C))
|
||
return -EINVAL;
|
||
|
||
/* Instead of trying to make the power_off code look like
|
||
* halt when pm_power_off is not set do it the easy way.
|
||
*/
|
||
if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
|
||
cmd = LINUX_REBOOT_CMD_HALT;
|
||
|
||
lock_kernel();
|
||
switch (cmd) {
|
||
case LINUX_REBOOT_CMD_RESTART:
|
||
kernel_restart(NULL);
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_CAD_ON:
|
||
C_A_D = 1;
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_CAD_OFF:
|
||
C_A_D = 0;
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_HALT:
|
||
kernel_halt();
|
||
unlock_kernel();
|
||
do_exit(0);
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_POWER_OFF:
|
||
kernel_power_off();
|
||
unlock_kernel();
|
||
do_exit(0);
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_RESTART2:
|
||
if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) {
|
||
unlock_kernel();
|
||
return -EFAULT;
|
||
}
|
||
buffer[sizeof(buffer) - 1] = '\0';
|
||
|
||
kernel_restart(buffer);
|
||
break;
|
||
|
||
case LINUX_REBOOT_CMD_KEXEC:
|
||
kernel_kexec();
|
||
unlock_kernel();
|
||
return -EINVAL;
|
||
|
||
#ifdef CONFIG_SOFTWARE_SUSPEND
|
||
case LINUX_REBOOT_CMD_SW_SUSPEND:
|
||
{
|
||
int ret = software_suspend();
|
||
unlock_kernel();
|
||
return ret;
|
||
}
|
||
#endif
|
||
|
||
default:
|
||
unlock_kernel();
|
||
return -EINVAL;
|
||
}
|
||
unlock_kernel();
|
||
return 0;
|
||
}
|
||
|
||
static void deferred_cad(void *dummy)
|
||
{
|
||
kernel_restart(NULL);
|
||
}
|
||
|
||
/*
|
||
* This function gets called by ctrl-alt-del - ie the keyboard interrupt.
|
||
* As it's called within an interrupt, it may NOT sync: the only choice
|
||
* is whether to reboot at once, or just ignore the ctrl-alt-del.
|
||
*/
|
||
void ctrl_alt_del(void)
|
||
{
|
||
static DECLARE_WORK(cad_work, deferred_cad, NULL);
|
||
|
||
if (C_A_D)
|
||
schedule_work(&cad_work);
|
||
else
|
||
kill_proc(cad_pid, SIGINT, 1);
|
||
}
|
||
|
||
|
||
/*
|
||
* Unprivileged users may change the real gid to the effective gid
|
||
* or vice versa. (BSD-style)
|
||
*
|
||
* If you set the real gid at all, or set the effective gid to a value not
|
||
* equal to the real gid, then the saved gid is set to the new effective gid.
|
||
*
|
||
* This makes it possible for a setgid program to completely drop its
|
||
* privileges, which is often a useful assertion to make when you are doing
|
||
* a security audit over a program.
|
||
*
|
||
* The general idea is that a program which uses just setregid() will be
|
||
* 100% compatible with BSD. A program which uses just setgid() will be
|
||
* 100% compatible with POSIX with saved IDs.
|
||
*
|
||
* SMP: There are not races, the GIDs are checked only by filesystem
|
||
* operations (as far as semantic preservation is concerned).
|
||
*/
|
||
asmlinkage long sys_setregid(gid_t rgid, gid_t egid)
|
||
{
|
||
int old_rgid = current->gid;
|
||
int old_egid = current->egid;
|
||
int new_rgid = old_rgid;
|
||
int new_egid = old_egid;
|
||
int retval;
|
||
|
||
retval = security_task_setgid(rgid, egid, (gid_t)-1, LSM_SETID_RE);
|
||
if (retval)
|
||
return retval;
|
||
|
||
if (rgid != (gid_t) -1) {
|
||
if ((old_rgid == rgid) ||
|
||
(current->egid==rgid) ||
|
||
capable(CAP_SETGID))
|
||
new_rgid = rgid;
|
||
else
|
||
return -EPERM;
|
||
}
|
||
if (egid != (gid_t) -1) {
|
||
if ((old_rgid == egid) ||
|
||
(current->egid == egid) ||
|
||
(current->sgid == egid) ||
|
||
capable(CAP_SETGID))
|
||
new_egid = egid;
|
||
else {
|
||
return -EPERM;
|
||
}
|
||
}
|
||
if (new_egid != old_egid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
if (rgid != (gid_t) -1 ||
|
||
(egid != (gid_t) -1 && egid != old_rgid))
|
||
current->sgid = new_egid;
|
||
current->fsgid = new_egid;
|
||
current->egid = new_egid;
|
||
current->gid = new_rgid;
|
||
key_fsgid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_GID);
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* setgid() is implemented like SysV w/ SAVED_IDS
|
||
*
|
||
* SMP: Same implicit races as above.
|
||
*/
|
||
asmlinkage long sys_setgid(gid_t gid)
|
||
{
|
||
int old_egid = current->egid;
|
||
int retval;
|
||
|
||
retval = security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_ID);
|
||
if (retval)
|
||
return retval;
|
||
|
||
if (capable(CAP_SETGID))
|
||
{
|
||
if(old_egid != gid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->gid = current->egid = current->sgid = current->fsgid = gid;
|
||
}
|
||
else if ((gid == current->gid) || (gid == current->sgid))
|
||
{
|
||
if(old_egid != gid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->egid = current->fsgid = gid;
|
||
}
|
||
else
|
||
return -EPERM;
|
||
|
||
key_fsgid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_GID);
|
||
return 0;
|
||
}
|
||
|
||
static int set_user(uid_t new_ruid, int dumpclear)
|
||
{
|
||
struct user_struct *new_user;
|
||
|
||
new_user = alloc_uid(new_ruid);
|
||
if (!new_user)
|
||
return -EAGAIN;
|
||
|
||
if (atomic_read(&new_user->processes) >=
|
||
current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
|
||
new_user != &root_user) {
|
||
free_uid(new_user);
|
||
return -EAGAIN;
|
||
}
|
||
|
||
switch_uid(new_user);
|
||
|
||
if(dumpclear)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->uid = new_ruid;
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* Unprivileged users may change the real uid to the effective uid
|
||
* or vice versa. (BSD-style)
|
||
*
|
||
* If you set the real uid at all, or set the effective uid to a value not
|
||
* equal to the real uid, then the saved uid is set to the new effective uid.
|
||
*
|
||
* This makes it possible for a setuid program to completely drop its
|
||
* privileges, which is often a useful assertion to make when you are doing
|
||
* a security audit over a program.
|
||
*
|
||
* The general idea is that a program which uses just setreuid() will be
|
||
* 100% compatible with BSD. A program which uses just setuid() will be
|
||
* 100% compatible with POSIX with saved IDs.
|
||
*/
|
||
asmlinkage long sys_setreuid(uid_t ruid, uid_t euid)
|
||
{
|
||
int old_ruid, old_euid, old_suid, new_ruid, new_euid;
|
||
int retval;
|
||
|
||
retval = security_task_setuid(ruid, euid, (uid_t)-1, LSM_SETID_RE);
|
||
if (retval)
|
||
return retval;
|
||
|
||
new_ruid = old_ruid = current->uid;
|
||
new_euid = old_euid = current->euid;
|
||
old_suid = current->suid;
|
||
|
||
if (ruid != (uid_t) -1) {
|
||
new_ruid = ruid;
|
||
if ((old_ruid != ruid) &&
|
||
(current->euid != ruid) &&
|
||
!capable(CAP_SETUID))
|
||
return -EPERM;
|
||
}
|
||
|
||
if (euid != (uid_t) -1) {
|
||
new_euid = euid;
|
||
if ((old_ruid != euid) &&
|
||
(current->euid != euid) &&
|
||
(current->suid != euid) &&
|
||
!capable(CAP_SETUID))
|
||
return -EPERM;
|
||
}
|
||
|
||
if (new_ruid != old_ruid && set_user(new_ruid, new_euid != old_euid) < 0)
|
||
return -EAGAIN;
|
||
|
||
if (new_euid != old_euid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->fsuid = current->euid = new_euid;
|
||
if (ruid != (uid_t) -1 ||
|
||
(euid != (uid_t) -1 && euid != old_ruid))
|
||
current->suid = current->euid;
|
||
current->fsuid = current->euid;
|
||
|
||
key_fsuid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_UID);
|
||
|
||
return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RE);
|
||
}
|
||
|
||
|
||
|
||
/*
|
||
* setuid() is implemented like SysV with SAVED_IDS
|
||
*
|
||
* Note that SAVED_ID's is deficient in that a setuid root program
|
||
* like sendmail, for example, cannot set its uid to be a normal
|
||
* user and then switch back, because if you're root, setuid() sets
|
||
* the saved uid too. If you don't like this, blame the bright people
|
||
* in the POSIX committee and/or USG. Note that the BSD-style setreuid()
|
||
* will allow a root program to temporarily drop privileges and be able to
|
||
* regain them by swapping the real and effective uid.
|
||
*/
|
||
asmlinkage long sys_setuid(uid_t uid)
|
||
{
|
||
int old_euid = current->euid;
|
||
int old_ruid, old_suid, new_ruid, new_suid;
|
||
int retval;
|
||
|
||
retval = security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_ID);
|
||
if (retval)
|
||
return retval;
|
||
|
||
old_ruid = new_ruid = current->uid;
|
||
old_suid = current->suid;
|
||
new_suid = old_suid;
|
||
|
||
if (capable(CAP_SETUID)) {
|
||
if (uid != old_ruid && set_user(uid, old_euid != uid) < 0)
|
||
return -EAGAIN;
|
||
new_suid = uid;
|
||
} else if ((uid != current->uid) && (uid != new_suid))
|
||
return -EPERM;
|
||
|
||
if (old_euid != uid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->fsuid = current->euid = uid;
|
||
current->suid = new_suid;
|
||
|
||
key_fsuid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_UID);
|
||
|
||
return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_ID);
|
||
}
|
||
|
||
|
||
/*
|
||
* This function implements a generic ability to update ruid, euid,
|
||
* and suid. This allows you to implement the 4.4 compatible seteuid().
|
||
*/
|
||
asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
|
||
{
|
||
int old_ruid = current->uid;
|
||
int old_euid = current->euid;
|
||
int old_suid = current->suid;
|
||
int retval;
|
||
|
||
retval = security_task_setuid(ruid, euid, suid, LSM_SETID_RES);
|
||
if (retval)
|
||
return retval;
|
||
|
||
if (!capable(CAP_SETUID)) {
|
||
if ((ruid != (uid_t) -1) && (ruid != current->uid) &&
|
||
(ruid != current->euid) && (ruid != current->suid))
|
||
return -EPERM;
|
||
if ((euid != (uid_t) -1) && (euid != current->uid) &&
|
||
(euid != current->euid) && (euid != current->suid))
|
||
return -EPERM;
|
||
if ((suid != (uid_t) -1) && (suid != current->uid) &&
|
||
(suid != current->euid) && (suid != current->suid))
|
||
return -EPERM;
|
||
}
|
||
if (ruid != (uid_t) -1) {
|
||
if (ruid != current->uid && set_user(ruid, euid != current->euid) < 0)
|
||
return -EAGAIN;
|
||
}
|
||
if (euid != (uid_t) -1) {
|
||
if (euid != current->euid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->euid = euid;
|
||
}
|
||
current->fsuid = current->euid;
|
||
if (suid != (uid_t) -1)
|
||
current->suid = suid;
|
||
|
||
key_fsuid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_UID);
|
||
|
||
return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES);
|
||
}
|
||
|
||
asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid)
|
||
{
|
||
int retval;
|
||
|
||
if (!(retval = put_user(current->uid, ruid)) &&
|
||
!(retval = put_user(current->euid, euid)))
|
||
retval = put_user(current->suid, suid);
|
||
|
||
return retval;
|
||
}
|
||
|
||
/*
|
||
* Same as above, but for rgid, egid, sgid.
|
||
*/
|
||
asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
|
||
{
|
||
int retval;
|
||
|
||
retval = security_task_setgid(rgid, egid, sgid, LSM_SETID_RES);
|
||
if (retval)
|
||
return retval;
|
||
|
||
if (!capable(CAP_SETGID)) {
|
||
if ((rgid != (gid_t) -1) && (rgid != current->gid) &&
|
||
(rgid != current->egid) && (rgid != current->sgid))
|
||
return -EPERM;
|
||
if ((egid != (gid_t) -1) && (egid != current->gid) &&
|
||
(egid != current->egid) && (egid != current->sgid))
|
||
return -EPERM;
|
||
if ((sgid != (gid_t) -1) && (sgid != current->gid) &&
|
||
(sgid != current->egid) && (sgid != current->sgid))
|
||
return -EPERM;
|
||
}
|
||
if (egid != (gid_t) -1) {
|
||
if (egid != current->egid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->egid = egid;
|
||
}
|
||
current->fsgid = current->egid;
|
||
if (rgid != (gid_t) -1)
|
||
current->gid = rgid;
|
||
if (sgid != (gid_t) -1)
|
||
current->sgid = sgid;
|
||
|
||
key_fsgid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_GID);
|
||
return 0;
|
||
}
|
||
|
||
asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid)
|
||
{
|
||
int retval;
|
||
|
||
if (!(retval = put_user(current->gid, rgid)) &&
|
||
!(retval = put_user(current->egid, egid)))
|
||
retval = put_user(current->sgid, sgid);
|
||
|
||
return retval;
|
||
}
|
||
|
||
|
||
/*
|
||
* "setfsuid()" sets the fsuid - the uid used for filesystem checks. This
|
||
* is used for "access()" and for the NFS daemon (letting nfsd stay at
|
||
* whatever uid it wants to). It normally shadows "euid", except when
|
||
* explicitly set by setfsuid() or for access..
|
||
*/
|
||
asmlinkage long sys_setfsuid(uid_t uid)
|
||
{
|
||
int old_fsuid;
|
||
|
||
old_fsuid = current->fsuid;
|
||
if (security_task_setuid(uid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS))
|
||
return old_fsuid;
|
||
|
||
if (uid == current->uid || uid == current->euid ||
|
||
uid == current->suid || uid == current->fsuid ||
|
||
capable(CAP_SETUID))
|
||
{
|
||
if (uid != old_fsuid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->fsuid = uid;
|
||
}
|
||
|
||
key_fsuid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_UID);
|
||
|
||
security_task_post_setuid(old_fsuid, (uid_t)-1, (uid_t)-1, LSM_SETID_FS);
|
||
|
||
return old_fsuid;
|
||
}
|
||
|
||
/*
|
||
* Samma p<> svenska..
|
||
*/
|
||
asmlinkage long sys_setfsgid(gid_t gid)
|
||
{
|
||
int old_fsgid;
|
||
|
||
old_fsgid = current->fsgid;
|
||
if (security_task_setgid(gid, (gid_t)-1, (gid_t)-1, LSM_SETID_FS))
|
||
return old_fsgid;
|
||
|
||
if (gid == current->gid || gid == current->egid ||
|
||
gid == current->sgid || gid == current->fsgid ||
|
||
capable(CAP_SETGID))
|
||
{
|
||
if (gid != old_fsgid)
|
||
{
|
||
current->mm->dumpable = suid_dumpable;
|
||
smp_wmb();
|
||
}
|
||
current->fsgid = gid;
|
||
key_fsgid_changed(current);
|
||
proc_id_connector(current, PROC_EVENT_GID);
|
||
}
|
||
return old_fsgid;
|
||
}
|
||
|
||
asmlinkage long sys_times(struct tms __user * tbuf)
|
||
{
|
||
/*
|
||
* In the SMP world we might just be unlucky and have one of
|
||
* the times increment as we use it. Since the value is an
|
||
* atomically safe type this is just fine. Conceptually its
|
||
* as if the syscall took an instant longer to occur.
|
||
*/
|
||
if (tbuf) {
|
||
struct tms tmp;
|
||
cputime_t utime, stime, cutime, cstime;
|
||
|
||
#ifdef CONFIG_SMP
|
||
if (thread_group_empty(current)) {
|
||
/*
|
||
* Single thread case without the use of any locks.
|
||
*
|
||
* We may race with release_task if two threads are
|
||
* executing. However, release task first adds up the
|
||
* counters (__exit_signal) before removing the task
|
||
* from the process tasklist (__unhash_process).
|
||
* __exit_signal also acquires and releases the
|
||
* siglock which results in the proper memory ordering
|
||
* so that the list modifications are always visible
|
||
* after the counters have been updated.
|
||
*
|
||
* If the counters have been updated by the second thread
|
||
* but the thread has not yet been removed from the list
|
||
* then the other branch will be executing which will
|
||
* block on tasklist_lock until the exit handling of the
|
||
* other task is finished.
|
||
*
|
||
* This also implies that the sighand->siglock cannot
|
||
* be held by another processor. So we can also
|
||
* skip acquiring that lock.
|
||
*/
|
||
utime = cputime_add(current->signal->utime, current->utime);
|
||
stime = cputime_add(current->signal->utime, current->stime);
|
||
cutime = current->signal->cutime;
|
||
cstime = current->signal->cstime;
|
||
} else
|
||
#endif
|
||
{
|
||
|
||
/* Process with multiple threads */
|
||
struct task_struct *tsk = current;
|
||
struct task_struct *t;
|
||
|
||
read_lock(&tasklist_lock);
|
||
utime = tsk->signal->utime;
|
||
stime = tsk->signal->stime;
|
||
t = tsk;
|
||
do {
|
||
utime = cputime_add(utime, t->utime);
|
||
stime = cputime_add(stime, t->stime);
|
||
t = next_thread(t);
|
||
} while (t != tsk);
|
||
|
||
/*
|
||
* While we have tasklist_lock read-locked, no dying thread
|
||
* can be updating current->signal->[us]time. Instead,
|
||
* we got their counts included in the live thread loop.
|
||
* However, another thread can come in right now and
|
||
* do a wait call that updates current->signal->c[us]time.
|
||
* To make sure we always see that pair updated atomically,
|
||
* we take the siglock around fetching them.
|
||
*/
|
||
spin_lock_irq(&tsk->sighand->siglock);
|
||
cutime = tsk->signal->cutime;
|
||
cstime = tsk->signal->cstime;
|
||
spin_unlock_irq(&tsk->sighand->siglock);
|
||
read_unlock(&tasklist_lock);
|
||
}
|
||
tmp.tms_utime = cputime_to_clock_t(utime);
|
||
tmp.tms_stime = cputime_to_clock_t(stime);
|
||
tmp.tms_cutime = cputime_to_clock_t(cutime);
|
||
tmp.tms_cstime = cputime_to_clock_t(cstime);
|
||
if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
|
||
return -EFAULT;
|
||
}
|
||
return (long) jiffies_64_to_clock_t(get_jiffies_64());
|
||
}
|
||
|
||
/*
|
||
* This needs some heavy checking ...
|
||
* I just haven't the stomach for it. I also don't fully
|
||
* understand sessions/pgrp etc. Let somebody who does explain it.
|
||
*
|
||
* OK, I think I have the protection semantics right.... this is really
|
||
* only important on a multi-user system anyway, to make sure one user
|
||
* can't send a signal to a process owned by another. -TYT, 12/12/91
|
||
*
|
||
* Auch. Had to add the 'did_exec' flag to conform completely to POSIX.
|
||
* LBT 04.03.94
|
||
*/
|
||
|
||
asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
|
||
{
|
||
struct task_struct *p;
|
||
struct task_struct *group_leader = current->group_leader;
|
||
int err = -EINVAL;
|
||
|
||
if (!pid)
|
||
pid = group_leader->pid;
|
||
if (!pgid)
|
||
pgid = pid;
|
||
if (pgid < 0)
|
||
return -EINVAL;
|
||
|
||
/* From this point forward we keep holding onto the tasklist lock
|
||
* so that our parent does not change from under us. -DaveM
|
||
*/
|
||
write_lock_irq(&tasklist_lock);
|
||
|
||
err = -ESRCH;
|
||
p = find_task_by_pid(pid);
|
||
if (!p)
|
||
goto out;
|
||
|
||
err = -EINVAL;
|
||
if (!thread_group_leader(p))
|
||
goto out;
|
||
|
||
if (p->real_parent == group_leader) {
|
||
err = -EPERM;
|
||
if (p->signal->session != group_leader->signal->session)
|
||
goto out;
|
||
err = -EACCES;
|
||
if (p->did_exec)
|
||
goto out;
|
||
} else {
|
||
err = -ESRCH;
|
||
if (p != group_leader)
|
||
goto out;
|
||
}
|
||
|
||
err = -EPERM;
|
||
if (p->signal->leader)
|
||
goto out;
|
||
|
||
if (pgid != pid) {
|
||
struct task_struct *p;
|
||
|
||
do_each_task_pid(pgid, PIDTYPE_PGID, p) {
|
||
if (p->signal->session == group_leader->signal->session)
|
||
goto ok_pgid;
|
||
} while_each_task_pid(pgid, PIDTYPE_PGID, p);
|
||
goto out;
|
||
}
|
||
|
||
ok_pgid:
|
||
err = security_task_setpgid(p, pgid);
|
||
if (err)
|
||
goto out;
|
||
|
||
if (process_group(p) != pgid) {
|
||
detach_pid(p, PIDTYPE_PGID);
|
||
p->signal->pgrp = pgid;
|
||
attach_pid(p, PIDTYPE_PGID, pgid);
|
||
}
|
||
|
||
err = 0;
|
||
out:
|
||
/* All paths lead to here, thus we are safe. -DaveM */
|
||
write_unlock_irq(&tasklist_lock);
|
||
return err;
|
||
}
|
||
|
||
asmlinkage long sys_getpgid(pid_t pid)
|
||
{
|
||
if (!pid) {
|
||
return process_group(current);
|
||
} else {
|
||
int retval;
|
||
struct task_struct *p;
|
||
|
||
read_lock(&tasklist_lock);
|
||
p = find_task_by_pid(pid);
|
||
|
||
retval = -ESRCH;
|
||
if (p) {
|
||
retval = security_task_getpgid(p);
|
||
if (!retval)
|
||
retval = process_group(p);
|
||
}
|
||
read_unlock(&tasklist_lock);
|
||
return retval;
|
||
}
|
||
}
|
||
|
||
#ifdef __ARCH_WANT_SYS_GETPGRP
|
||
|
||
asmlinkage long sys_getpgrp(void)
|
||
{
|
||
/* SMP - assuming writes are word atomic this is fine */
|
||
return process_group(current);
|
||
}
|
||
|
||
#endif
|
||
|
||
asmlinkage long sys_getsid(pid_t pid)
|
||
{
|
||
if (!pid) {
|
||
return current->signal->session;
|
||
} else {
|
||
int retval;
|
||
struct task_struct *p;
|
||
|
||
read_lock(&tasklist_lock);
|
||
p = find_task_by_pid(pid);
|
||
|
||
retval = -ESRCH;
|
||
if(p) {
|
||
retval = security_task_getsid(p);
|
||
if (!retval)
|
||
retval = p->signal->session;
|
||
}
|
||
read_unlock(&tasklist_lock);
|
||
return retval;
|
||
}
|
||
}
|
||
|
||
asmlinkage long sys_setsid(void)
|
||
{
|
||
struct task_struct *group_leader = current->group_leader;
|
||
struct pid *pid;
|
||
int err = -EPERM;
|
||
|
||
mutex_lock(&tty_mutex);
|
||
write_lock_irq(&tasklist_lock);
|
||
|
||
pid = find_pid(PIDTYPE_PGID, group_leader->pid);
|
||
if (pid)
|
||
goto out;
|
||
|
||
group_leader->signal->leader = 1;
|
||
__set_special_pids(group_leader->pid, group_leader->pid);
|
||
group_leader->signal->tty = NULL;
|
||
group_leader->signal->tty_old_pgrp = 0;
|
||
err = process_group(group_leader);
|
||
out:
|
||
write_unlock_irq(&tasklist_lock);
|
||
mutex_unlock(&tty_mutex);
|
||
return err;
|
||
}
|
||
|
||
/*
|
||
* Supplementary group IDs
|
||
*/
|
||
|
||
/* init to 2 - one for init_task, one to ensure it is never freed */
|
||
struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
|
||
|
||
struct group_info *groups_alloc(int gidsetsize)
|
||
{
|
||
struct group_info *group_info;
|
||
int nblocks;
|
||
int i;
|
||
|
||
nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK;
|
||
/* Make sure we always allocate at least one indirect block pointer */
|
||
nblocks = nblocks ? : 1;
|
||
group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER);
|
||
if (!group_info)
|
||
return NULL;
|
||
group_info->ngroups = gidsetsize;
|
||
group_info->nblocks = nblocks;
|
||
atomic_set(&group_info->usage, 1);
|
||
|
||
if (gidsetsize <= NGROUPS_SMALL) {
|
||
group_info->blocks[0] = group_info->small_block;
|
||
} else {
|
||
for (i = 0; i < nblocks; i++) {
|
||
gid_t *b;
|
||
b = (void *)__get_free_page(GFP_USER);
|
||
if (!b)
|
||
goto out_undo_partial_alloc;
|
||
group_info->blocks[i] = b;
|
||
}
|
||
}
|
||
return group_info;
|
||
|
||
out_undo_partial_alloc:
|
||
while (--i >= 0) {
|
||
free_page((unsigned long)group_info->blocks[i]);
|
||
}
|
||
kfree(group_info);
|
||
return NULL;
|
||
}
|
||
|
||
EXPORT_SYMBOL(groups_alloc);
|
||
|
||
void groups_free(struct group_info *group_info)
|
||
{
|
||
if (group_info->blocks[0] != group_info->small_block) {
|
||
int i;
|
||
for (i = 0; i < group_info->nblocks; i++)
|
||
free_page((unsigned long)group_info->blocks[i]);
|
||
}
|
||
kfree(group_info);
|
||
}
|
||
|
||
EXPORT_SYMBOL(groups_free);
|
||
|
||
/* export the group_info to a user-space array */
|
||
static int groups_to_user(gid_t __user *grouplist,
|
||
struct group_info *group_info)
|
||
{
|
||
int i;
|
||
int count = group_info->ngroups;
|
||
|
||
for (i = 0; i < group_info->nblocks; i++) {
|
||
int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||
int off = i * NGROUPS_PER_BLOCK;
|
||
int len = cp_count * sizeof(*grouplist);
|
||
|
||
if (copy_to_user(grouplist+off, group_info->blocks[i], len))
|
||
return -EFAULT;
|
||
|
||
count -= cp_count;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* fill a group_info from a user-space array - it must be allocated already */
|
||
static int groups_from_user(struct group_info *group_info,
|
||
gid_t __user *grouplist)
|
||
{
|
||
int i;
|
||
int count = group_info->ngroups;
|
||
|
||
for (i = 0; i < group_info->nblocks; i++) {
|
||
int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||
int off = i * NGROUPS_PER_BLOCK;
|
||
int len = cp_count * sizeof(*grouplist);
|
||
|
||
if (copy_from_user(group_info->blocks[i], grouplist+off, len))
|
||
return -EFAULT;
|
||
|
||
count -= cp_count;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* a simple Shell sort */
|
||
static void groups_sort(struct group_info *group_info)
|
||
{
|
||
int base, max, stride;
|
||
int gidsetsize = group_info->ngroups;
|
||
|
||
for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
|
||
; /* nothing */
|
||
stride /= 3;
|
||
|
||
while (stride) {
|
||
max = gidsetsize - stride;
|
||
for (base = 0; base < max; base++) {
|
||
int left = base;
|
||
int right = left + stride;
|
||
gid_t tmp = GROUP_AT(group_info, right);
|
||
|
||
while (left >= 0 && GROUP_AT(group_info, left) > tmp) {
|
||
GROUP_AT(group_info, right) =
|
||
GROUP_AT(group_info, left);
|
||
right = left;
|
||
left -= stride;
|
||
}
|
||
GROUP_AT(group_info, right) = tmp;
|
||
}
|
||
stride /= 3;
|
||
}
|
||
}
|
||
|
||
/* a simple bsearch */
|
||
int groups_search(struct group_info *group_info, gid_t grp)
|
||
{
|
||
unsigned int left, right;
|
||
|
||
if (!group_info)
|
||
return 0;
|
||
|
||
left = 0;
|
||
right = group_info->ngroups;
|
||
while (left < right) {
|
||
unsigned int mid = (left+right)/2;
|
||
int cmp = grp - GROUP_AT(group_info, mid);
|
||
if (cmp > 0)
|
||
left = mid + 1;
|
||
else if (cmp < 0)
|
||
right = mid;
|
||
else
|
||
return 1;
|
||
}
|
||
return 0;
|
||
}
|
||
|
||
/* validate and set current->group_info */
|
||
int set_current_groups(struct group_info *group_info)
|
||
{
|
||
int retval;
|
||
struct group_info *old_info;
|
||
|
||
retval = security_task_setgroups(group_info);
|
||
if (retval)
|
||
return retval;
|
||
|
||
groups_sort(group_info);
|
||
get_group_info(group_info);
|
||
|
||
task_lock(current);
|
||
old_info = current->group_info;
|
||
current->group_info = group_info;
|
||
task_unlock(current);
|
||
|
||
put_group_info(old_info);
|
||
|
||
return 0;
|
||
}
|
||
|
||
EXPORT_SYMBOL(set_current_groups);
|
||
|
||
asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist)
|
||
{
|
||
int i = 0;
|
||
|
||
/*
|
||
* SMP: Nobody else can change our grouplist. Thus we are
|
||
* safe.
|
||
*/
|
||
|
||
if (gidsetsize < 0)
|
||
return -EINVAL;
|
||
|
||
/* no need to grab task_lock here; it cannot change */
|
||
i = current->group_info->ngroups;
|
||
if (gidsetsize) {
|
||
if (i > gidsetsize) {
|
||
i = -EINVAL;
|
||
goto out;
|
||
}
|
||
if (groups_to_user(grouplist, current->group_info)) {
|
||
i = -EFAULT;
|
||
goto out;
|
||
}
|
||
}
|
||
out:
|
||
return i;
|
||
}
|
||
|
||
/*
|
||
* SMP: Our groups are copy-on-write. We can set them safely
|
||
* without another task interfering.
|
||
*/
|
||
|
||
asmlinkage long sys_setgroups(int gidsetsize, gid_t __user *grouplist)
|
||
{
|
||
struct group_info *group_info;
|
||
int retval;
|
||
|
||
if (!capable(CAP_SETGID))
|
||
return -EPERM;
|
||
if ((unsigned)gidsetsize > NGROUPS_MAX)
|
||
return -EINVAL;
|
||
|
||
group_info = groups_alloc(gidsetsize);
|
||
if (!group_info)
|
||
return -ENOMEM;
|
||
retval = groups_from_user(group_info, grouplist);
|
||
if (retval) {
|
||
put_group_info(group_info);
|
||
return retval;
|
||
}
|
||
|
||
retval = set_current_groups(group_info);
|
||
put_group_info(group_info);
|
||
|
||
return retval;
|
||
}
|
||
|
||
/*
|
||
* Check whether we're fsgid/egid or in the supplemental group..
|
||
*/
|
||
int in_group_p(gid_t grp)
|
||
{
|
||
int retval = 1;
|
||
if (grp != current->fsgid) {
|
||
retval = groups_search(current->group_info, grp);
|
||
}
|
||
return retval;
|
||
}
|
||
|
||
EXPORT_SYMBOL(in_group_p);
|
||
|
||
int in_egroup_p(gid_t grp)
|
||
{
|
||
int retval = 1;
|
||
if (grp != current->egid) {
|
||
retval = groups_search(current->group_info, grp);
|
||
}
|
||
return retval;
|
||
}
|
||
|
||
EXPORT_SYMBOL(in_egroup_p);
|
||
|
||
DECLARE_RWSEM(uts_sem);
|
||
|
||
EXPORT_SYMBOL(uts_sem);
|
||
|
||
asmlinkage long sys_newuname(struct new_utsname __user * name)
|
||
{
|
||
int errno = 0;
|
||
|
||
down_read(&uts_sem);
|
||
if (copy_to_user(name,&system_utsname,sizeof *name))
|
||
errno = -EFAULT;
|
||
up_read(&uts_sem);
|
||
return errno;
|
||
}
|
||
|
||
asmlinkage long sys_sethostname(char __user *name, int len)
|
||
{
|
||
int errno;
|
||
char tmp[__NEW_UTS_LEN];
|
||
|
||
if (!capable(CAP_SYS_ADMIN))
|
||
return -EPERM;
|
||
if (len < 0 || len > __NEW_UTS_LEN)
|
||
return -EINVAL;
|
||
down_write(&uts_sem);
|
||
errno = -EFAULT;
|
||
if (!copy_from_user(tmp, name, len)) {
|
||
memcpy(system_utsname.nodename, tmp, len);
|
||
system_utsname.nodename[len] = 0;
|
||
errno = 0;
|
||
}
|
||
up_write(&uts_sem);
|
||
return errno;
|
||
}
|
||
|
||
#ifdef __ARCH_WANT_SYS_GETHOSTNAME
|
||
|
||
asmlinkage long sys_gethostname(char __user *name, int len)
|
||
{
|
||
int i, errno;
|
||
|
||
if (len < 0)
|
||
return -EINVAL;
|
||
down_read(&uts_sem);
|
||
i = 1 + strlen(system_utsname.nodename);
|
||
if (i > len)
|
||
i = len;
|
||
errno = 0;
|
||
if (copy_to_user(name, system_utsname.nodename, i))
|
||
errno = -EFAULT;
|
||
up_read(&uts_sem);
|
||
return errno;
|
||
}
|
||
|
||
#endif
|
||
|
||
/*
|
||
* Only setdomainname; getdomainname can be implemented by calling
|
||
* uname()
|
||
*/
|
||
asmlinkage long sys_setdomainname(char __user *name, int len)
|
||
{
|
||
int errno;
|
||
char tmp[__NEW_UTS_LEN];
|
||
|
||
if (!capable(CAP_SYS_ADMIN))
|
||
return -EPERM;
|
||
if (len < 0 || len > __NEW_UTS_LEN)
|
||
return -EINVAL;
|
||
|
||
down_write(&uts_sem);
|
||
errno = -EFAULT;
|
||
if (!copy_from_user(tmp, name, len)) {
|
||
memcpy(system_utsname.domainname, tmp, len);
|
||
system_utsname.domainname[len] = 0;
|
||
errno = 0;
|
||
}
|
||
up_write(&uts_sem);
|
||
return errno;
|
||
}
|
||
|
||
asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim)
|
||
{
|
||
if (resource >= RLIM_NLIMITS)
|
||
return -EINVAL;
|
||
else {
|
||
struct rlimit value;
|
||
task_lock(current->group_leader);
|
||
value = current->signal->rlim[resource];
|
||
task_unlock(current->group_leader);
|
||
return copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0;
|
||
}
|
||
}
|
||
|
||
#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
|
||
|
||
/*
|
||
* Back compatibility for getrlimit. Needed for some apps.
|
||
*/
|
||
|
||
asmlinkage long sys_old_getrlimit(unsigned int resource, struct rlimit __user *rlim)
|
||
{
|
||
struct rlimit x;
|
||
if (resource >= RLIM_NLIMITS)
|
||
return -EINVAL;
|
||
|
||
task_lock(current->group_leader);
|
||
x = current->signal->rlim[resource];
|
||
task_unlock(current->group_leader);
|
||
if(x.rlim_cur > 0x7FFFFFFF)
|
||
x.rlim_cur = 0x7FFFFFFF;
|
||
if(x.rlim_max > 0x7FFFFFFF)
|
||
x.rlim_max = 0x7FFFFFFF;
|
||
return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0;
|
||
}
|
||
|
||
#endif
|
||
|
||
asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim)
|
||
{
|
||
struct rlimit new_rlim, *old_rlim;
|
||
unsigned long it_prof_secs;
|
||
int retval;
|
||
|
||
if (resource >= RLIM_NLIMITS)
|
||
return -EINVAL;
|
||
if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
|
||
return -EFAULT;
|
||
if (new_rlim.rlim_cur > new_rlim.rlim_max)
|
||
return -EINVAL;
|
||
old_rlim = current->signal->rlim + resource;
|
||
if ((new_rlim.rlim_max > old_rlim->rlim_max) &&
|
||
!capable(CAP_SYS_RESOURCE))
|
||
return -EPERM;
|
||
if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > NR_OPEN)
|
||
return -EPERM;
|
||
|
||
retval = security_task_setrlimit(resource, &new_rlim);
|
||
if (retval)
|
||
return retval;
|
||
|
||
task_lock(current->group_leader);
|
||
*old_rlim = new_rlim;
|
||
task_unlock(current->group_leader);
|
||
|
||
if (resource != RLIMIT_CPU)
|
||
goto out;
|
||
|
||
/*
|
||
* RLIMIT_CPU handling. Note that the kernel fails to return an error
|
||
* code if it rejected the user's attempt to set RLIMIT_CPU. This is a
|
||
* very long-standing error, and fixing it now risks breakage of
|
||
* applications, so we live with it
|
||
*/
|
||
if (new_rlim.rlim_cur == RLIM_INFINITY)
|
||
goto out;
|
||
|
||
it_prof_secs = cputime_to_secs(current->signal->it_prof_expires);
|
||
if (it_prof_secs == 0 || new_rlim.rlim_cur <= it_prof_secs) {
|
||
unsigned long rlim_cur = new_rlim.rlim_cur;
|
||
cputime_t cputime;
|
||
|
||
if (rlim_cur == 0) {
|
||
/*
|
||
* The caller is asking for an immediate RLIMIT_CPU
|
||
* expiry. But we use the zero value to mean "it was
|
||
* never set". So let's cheat and make it one second
|
||
* instead
|
||
*/
|
||
rlim_cur = 1;
|
||
}
|
||
cputime = secs_to_cputime(rlim_cur);
|
||
read_lock(&tasklist_lock);
|
||
spin_lock_irq(¤t->sighand->siglock);
|
||
set_process_cpu_timer(current, CPUCLOCK_PROF, &cputime, NULL);
|
||
spin_unlock_irq(¤t->sighand->siglock);
|
||
read_unlock(&tasklist_lock);
|
||
}
|
||
out:
|
||
return 0;
|
||
}
|
||
|
||
/*
|
||
* It would make sense to put struct rusage in the task_struct,
|
||
* except that would make the task_struct be *really big*. After
|
||
* task_struct gets moved into malloc'ed memory, it would
|
||
* make sense to do this. It will make moving the rest of the information
|
||
* a lot simpler! (Which we're not doing right now because we're not
|
||
* measuring them yet).
|
||
*
|
||
* When sampling multiple threads for RUSAGE_SELF, under SMP we might have
|
||
* races with threads incrementing their own counters. But since word
|
||
* reads are atomic, we either get new values or old values and we don't
|
||
* care which for the sums. We always take the siglock to protect reading
|
||
* the c* fields from p->signal from races with exit.c updating those
|
||
* fields when reaping, so a sample either gets all the additions of a
|
||
* given child after it's reaped, or none so this sample is before reaping.
|
||
*
|
||
* tasklist_lock locking optimisation:
|
||
* If we are current and single threaded, we do not need to take the tasklist
|
||
* lock or the siglock. No one else can take our signal_struct away,
|
||
* no one else can reap the children to update signal->c* counters, and
|
||
* no one else can race with the signal-> fields.
|
||
* If we do not take the tasklist_lock, the signal-> fields could be read
|
||
* out of order while another thread was just exiting. So we place a
|
||
* read memory barrier when we avoid the lock. On the writer side,
|
||
* write memory barrier is implied in __exit_signal as __exit_signal releases
|
||
* the siglock spinlock after updating the signal-> fields.
|
||
*
|
||
* We don't really need the siglock when we access the non c* fields
|
||
* of the signal_struct (for RUSAGE_SELF) even in multithreaded
|
||
* case, since we take the tasklist lock for read and the non c* signal->
|
||
* fields are updated only in __exit_signal, which is called with
|
||
* tasklist_lock taken for write, hence these two threads cannot execute
|
||
* concurrently.
|
||
*
|
||
*/
|
||
|
||
static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
|
||
{
|
||
struct task_struct *t;
|
||
unsigned long flags;
|
||
cputime_t utime, stime;
|
||
int need_lock = 0;
|
||
|
||
memset((char *) r, 0, sizeof *r);
|
||
utime = stime = cputime_zero;
|
||
|
||
if (p != current || !thread_group_empty(p))
|
||
need_lock = 1;
|
||
|
||
if (need_lock) {
|
||
read_lock(&tasklist_lock);
|
||
if (unlikely(!p->signal)) {
|
||
read_unlock(&tasklist_lock);
|
||
return;
|
||
}
|
||
} else
|
||
/* See locking comments above */
|
||
smp_rmb();
|
||
|
||
switch (who) {
|
||
case RUSAGE_BOTH:
|
||
case RUSAGE_CHILDREN:
|
||
spin_lock_irqsave(&p->sighand->siglock, flags);
|
||
utime = p->signal->cutime;
|
||
stime = p->signal->cstime;
|
||
r->ru_nvcsw = p->signal->cnvcsw;
|
||
r->ru_nivcsw = p->signal->cnivcsw;
|
||
r->ru_minflt = p->signal->cmin_flt;
|
||
r->ru_majflt = p->signal->cmaj_flt;
|
||
spin_unlock_irqrestore(&p->sighand->siglock, flags);
|
||
|
||
if (who == RUSAGE_CHILDREN)
|
||
break;
|
||
|
||
case RUSAGE_SELF:
|
||
utime = cputime_add(utime, p->signal->utime);
|
||
stime = cputime_add(stime, p->signal->stime);
|
||
r->ru_nvcsw += p->signal->nvcsw;
|
||
r->ru_nivcsw += p->signal->nivcsw;
|
||
r->ru_minflt += p->signal->min_flt;
|
||
r->ru_majflt += p->signal->maj_flt;
|
||
t = p;
|
||
do {
|
||
utime = cputime_add(utime, t->utime);
|
||
stime = cputime_add(stime, t->stime);
|
||
r->ru_nvcsw += t->nvcsw;
|
||
r->ru_nivcsw += t->nivcsw;
|
||
r->ru_minflt += t->min_flt;
|
||
r->ru_majflt += t->maj_flt;
|
||
t = next_thread(t);
|
||
} while (t != p);
|
||
break;
|
||
|
||
default:
|
||
BUG();
|
||
}
|
||
|
||
if (need_lock)
|
||
read_unlock(&tasklist_lock);
|
||
cputime_to_timeval(utime, &r->ru_utime);
|
||
cputime_to_timeval(stime, &r->ru_stime);
|
||
}
|
||
|
||
int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
|
||
{
|
||
struct rusage r;
|
||
k_getrusage(p, who, &r);
|
||
return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
|
||
}
|
||
|
||
asmlinkage long sys_getrusage(int who, struct rusage __user *ru)
|
||
{
|
||
if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
|
||
return -EINVAL;
|
||
return getrusage(current, who, ru);
|
||
}
|
||
|
||
asmlinkage long sys_umask(int mask)
|
||
{
|
||
mask = xchg(¤t->fs->umask, mask & S_IRWXUGO);
|
||
return mask;
|
||
}
|
||
|
||
asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
|
||
unsigned long arg4, unsigned long arg5)
|
||
{
|
||
long error;
|
||
|
||
error = security_task_prctl(option, arg2, arg3, arg4, arg5);
|
||
if (error)
|
||
return error;
|
||
|
||
switch (option) {
|
||
case PR_SET_PDEATHSIG:
|
||
if (!valid_signal(arg2)) {
|
||
error = -EINVAL;
|
||
break;
|
||
}
|
||
current->pdeath_signal = arg2;
|
||
break;
|
||
case PR_GET_PDEATHSIG:
|
||
error = put_user(current->pdeath_signal, (int __user *)arg2);
|
||
break;
|
||
case PR_GET_DUMPABLE:
|
||
error = current->mm->dumpable;
|
||
break;
|
||
case PR_SET_DUMPABLE:
|
||
if (arg2 < 0 || arg2 > 2) {
|
||
error = -EINVAL;
|
||
break;
|
||
}
|
||
current->mm->dumpable = arg2;
|
||
break;
|
||
|
||
case PR_SET_UNALIGN:
|
||
error = SET_UNALIGN_CTL(current, arg2);
|
||
break;
|
||
case PR_GET_UNALIGN:
|
||
error = GET_UNALIGN_CTL(current, arg2);
|
||
break;
|
||
case PR_SET_FPEMU:
|
||
error = SET_FPEMU_CTL(current, arg2);
|
||
break;
|
||
case PR_GET_FPEMU:
|
||
error = GET_FPEMU_CTL(current, arg2);
|
||
break;
|
||
case PR_SET_FPEXC:
|
||
error = SET_FPEXC_CTL(current, arg2);
|
||
break;
|
||
case PR_GET_FPEXC:
|
||
error = GET_FPEXC_CTL(current, arg2);
|
||
break;
|
||
case PR_GET_TIMING:
|
||
error = PR_TIMING_STATISTICAL;
|
||
break;
|
||
case PR_SET_TIMING:
|
||
if (arg2 == PR_TIMING_STATISTICAL)
|
||
error = 0;
|
||
else
|
||
error = -EINVAL;
|
||
break;
|
||
|
||
case PR_GET_KEEPCAPS:
|
||
if (current->keep_capabilities)
|
||
error = 1;
|
||
break;
|
||
case PR_SET_KEEPCAPS:
|
||
if (arg2 != 0 && arg2 != 1) {
|
||
error = -EINVAL;
|
||
break;
|
||
}
|
||
current->keep_capabilities = arg2;
|
||
break;
|
||
case PR_SET_NAME: {
|
||
struct task_struct *me = current;
|
||
unsigned char ncomm[sizeof(me->comm)];
|
||
|
||
ncomm[sizeof(me->comm)-1] = 0;
|
||
if (strncpy_from_user(ncomm, (char __user *)arg2,
|
||
sizeof(me->comm)-1) < 0)
|
||
return -EFAULT;
|
||
set_task_comm(me, ncomm);
|
||
return 0;
|
||
}
|
||
case PR_GET_NAME: {
|
||
struct task_struct *me = current;
|
||
unsigned char tcomm[sizeof(me->comm)];
|
||
|
||
get_task_comm(tcomm, me);
|
||
if (copy_to_user((char __user *)arg2, tcomm, sizeof(tcomm)))
|
||
return -EFAULT;
|
||
return 0;
|
||
}
|
||
default:
|
||
error = -EINVAL;
|
||
break;
|
||
}
|
||
return error;
|
||
}
|