/******************************************************************************
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* platform-pci-unplug.c
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*
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* Xen platform PCI device driver
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* Copyright (c) 2010, Citrix
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
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* Place - Suite 330, Boston, MA 02111-1307 USA.
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*
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*/
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#include <linux/init.h>
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#include <linux/io.h>
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#include <linux/export.h>
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#include <xen/platform_pci.h>
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#include "xen-ops.h"
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#define XEN_PLATFORM_ERR_MAGIC -1
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#define XEN_PLATFORM_ERR_PROTOCOL -2
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#define XEN_PLATFORM_ERR_BLACKLIST -3
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#ifdef CONFIG_XEN_PVHVM
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/* store the value of xen_emul_unplug after the unplug is done */
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static int xen_platform_pci_unplug;
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static int xen_emul_unplug;
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static int check_platform_magic(void)
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{
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short magic;
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char protocol;
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magic = inw(XEN_IOPORT_MAGIC);
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if (magic != XEN_IOPORT_MAGIC_VAL) {
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printk(KERN_ERR "Xen Platform PCI: unrecognised magic value\n");
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return XEN_PLATFORM_ERR_MAGIC;
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}
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protocol = inb(XEN_IOPORT_PROTOVER);
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printk(KERN_DEBUG "Xen Platform PCI: I/O protocol version %d\n",
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protocol);
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switch (protocol) {
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case 1:
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outw(XEN_IOPORT_LINUX_PRODNUM, XEN_IOPORT_PRODNUM);
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outl(XEN_IOPORT_LINUX_DRVVER, XEN_IOPORT_DRVVER);
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if (inw(XEN_IOPORT_MAGIC) != XEN_IOPORT_MAGIC_VAL) {
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printk(KERN_ERR "Xen Platform: blacklisted by host\n");
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return XEN_PLATFORM_ERR_BLACKLIST;
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}
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break;
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default:
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printk(KERN_WARNING "Xen Platform PCI: unknown I/O protocol version\n");
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return XEN_PLATFORM_ERR_PROTOCOL;
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}
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return 0;
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}
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bool xen_has_pv_devices(void)
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{
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if (!xen_domain())
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return false;
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/* PV and PVH domains always have them. */
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if (xen_pv_domain() || xen_pvh_domain())
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return true;
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/* And user has xen_platform_pci=0 set in guest config as
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* driver did not modify the value. */
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if (xen_platform_pci_unplug == 0)
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return false;
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if (xen_platform_pci_unplug & XEN_UNPLUG_NEVER)
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return false;
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if (xen_platform_pci_unplug & XEN_UNPLUG_ALL)
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return true;
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/* This is an odd one - we are going to run legacy
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* and PV drivers at the same time. */
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if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY)
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return true;
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/* And the caller has to follow with xen_pv_{disk,nic}_devices
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* to be certain which driver can load. */
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return false;
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}
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EXPORT_SYMBOL_GPL(xen_has_pv_devices);
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static bool __xen_has_pv_device(int state)
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{
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/* HVM domains might or might not */
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if (xen_hvm_domain() && (xen_platform_pci_unplug & state))
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return true;
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return xen_has_pv_devices();
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}
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bool xen_has_pv_nic_devices(void)
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{
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return __xen_has_pv_device(XEN_UNPLUG_ALL_NICS | XEN_UNPLUG_ALL);
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}
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EXPORT_SYMBOL_GPL(xen_has_pv_nic_devices);
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bool xen_has_pv_disk_devices(void)
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{
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return __xen_has_pv_device(XEN_UNPLUG_ALL_IDE_DISKS |
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XEN_UNPLUG_AUX_IDE_DISKS | XEN_UNPLUG_ALL);
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}
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EXPORT_SYMBOL_GPL(xen_has_pv_disk_devices);
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/*
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* This one is odd - it determines whether you want to run PV _and_
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* legacy (IDE) drivers together. This combination is only possible
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* under HVM.
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*/
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bool xen_has_pv_and_legacy_disk_devices(void)
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{
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if (!xen_domain())
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return false;
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/* N.B. This is only ever used in HVM mode */
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if (xen_pv_domain())
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return false;
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if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY)
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return true;
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return false;
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}
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EXPORT_SYMBOL_GPL(xen_has_pv_and_legacy_disk_devices);
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void xen_unplug_emulated_devices(void)
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{
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int r;
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/* PVH guests don't have emulated devices. */
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if (xen_pvh_domain())
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return;
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/* user explicitly requested no unplug */
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if (xen_emul_unplug & XEN_UNPLUG_NEVER)
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return;
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/* check the version of the xen platform PCI device */
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r = check_platform_magic();
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/* If the version matches enable the Xen platform PCI driver.
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* Also enable the Xen platform PCI driver if the host does
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* not support the unplug protocol (XEN_PLATFORM_ERR_MAGIC)
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* but the user told us that unplugging is unnecessary. */
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if (r && !(r == XEN_PLATFORM_ERR_MAGIC &&
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(xen_emul_unplug & XEN_UNPLUG_UNNECESSARY)))
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return;
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/* Set the default value of xen_emul_unplug depending on whether or
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* not the Xen PV frontends and the Xen platform PCI driver have
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* been compiled for this kernel (modules or built-in are both OK). */
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if (!xen_emul_unplug) {
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if (xen_must_unplug_nics()) {
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printk(KERN_INFO "Netfront and the Xen platform PCI driver have "
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"been compiled for this kernel: unplug emulated NICs.\n");
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xen_emul_unplug |= XEN_UNPLUG_ALL_NICS;
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}
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if (xen_must_unplug_disks()) {
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printk(KERN_INFO "Blkfront and the Xen platform PCI driver have "
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"been compiled for this kernel: unplug emulated disks.\n"
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"You might have to change the root device\n"
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"from /dev/hd[a-d] to /dev/xvd[a-d]\n"
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"in your root= kernel command line option\n");
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xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS;
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}
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}
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/* Now unplug the emulated devices */
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if (!(xen_emul_unplug & XEN_UNPLUG_UNNECESSARY))
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outw(xen_emul_unplug, XEN_IOPORT_UNPLUG);
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xen_platform_pci_unplug = xen_emul_unplug;
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}
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static int __init parse_xen_emul_unplug(char *arg)
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{
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char *p, *q;
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int l;
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for (p = arg; p; p = q) {
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q = strchr(p, ',');
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if (q) {
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l = q - p;
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q++;
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} else {
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l = strlen(p);
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}
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if (!strncmp(p, "all", l))
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xen_emul_unplug |= XEN_UNPLUG_ALL;
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else if (!strncmp(p, "ide-disks", l))
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xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS;
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else if (!strncmp(p, "aux-ide-disks", l))
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xen_emul_unplug |= XEN_UNPLUG_AUX_IDE_DISKS;
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else if (!strncmp(p, "nics", l))
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xen_emul_unplug |= XEN_UNPLUG_ALL_NICS;
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else if (!strncmp(p, "unnecessary", l))
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xen_emul_unplug |= XEN_UNPLUG_UNNECESSARY;
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else if (!strncmp(p, "never", l))
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xen_emul_unplug |= XEN_UNPLUG_NEVER;
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else
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printk(KERN_WARNING "unrecognised option '%s' "
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"in parameter 'xen_emul_unplug'\n", p);
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}
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return 0;
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}
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early_param("xen_emul_unplug", parse_xen_emul_unplug);
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#endif
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