/****************************************************************************** * platform-pci-unplug.c * * Xen platform PCI device driver * Copyright (c) 2010, Citrix * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope 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. * */ #include #include #include #include #include "xen-ops.h" #define XEN_PLATFORM_ERR_MAGIC -1 #define XEN_PLATFORM_ERR_PROTOCOL -2 #define XEN_PLATFORM_ERR_BLACKLIST -3 #ifdef CONFIG_XEN_PVHVM /* store the value of xen_emul_unplug after the unplug is done */ static int xen_platform_pci_unplug; static int xen_emul_unplug; static int check_platform_magic(void) { short magic; char protocol; magic = inw(XEN_IOPORT_MAGIC); if (magic != XEN_IOPORT_MAGIC_VAL) { printk(KERN_ERR "Xen Platform PCI: unrecognised magic value\n"); return XEN_PLATFORM_ERR_MAGIC; } protocol = inb(XEN_IOPORT_PROTOVER); printk(KERN_DEBUG "Xen Platform PCI: I/O protocol version %d\n", protocol); switch (protocol) { case 1: outw(XEN_IOPORT_LINUX_PRODNUM, XEN_IOPORT_PRODNUM); outl(XEN_IOPORT_LINUX_DRVVER, XEN_IOPORT_DRVVER); if (inw(XEN_IOPORT_MAGIC) != XEN_IOPORT_MAGIC_VAL) { printk(KERN_ERR "Xen Platform: blacklisted by host\n"); return XEN_PLATFORM_ERR_BLACKLIST; } break; default: printk(KERN_WARNING "Xen Platform PCI: unknown I/O protocol version"); return XEN_PLATFORM_ERR_PROTOCOL; } return 0; } bool xen_has_pv_devices() { if (!xen_domain()) return false; /* PV domains always have them. */ if (xen_pv_domain()) return true; /* And user has xen_platform_pci=0 set in guest config as * driver did not modify the value. */ if (xen_platform_pci_unplug == 0) return false; if (xen_platform_pci_unplug & XEN_UNPLUG_NEVER) return false; if (xen_platform_pci_unplug & XEN_UNPLUG_ALL) return true; /* This is an odd one - we are going to run legacy * and PV drivers at the same time. */ if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY) return true; /* And the caller has to follow with xen_pv_{disk,nic}_devices * to be certain which driver can load. */ return false; } EXPORT_SYMBOL_GPL(xen_has_pv_devices); static bool __xen_has_pv_device(int state) { /* HVM domains might or might not */ if (xen_hvm_domain() && (xen_platform_pci_unplug & state)) return true; return xen_has_pv_devices(); } bool xen_has_pv_nic_devices(void) { return __xen_has_pv_device(XEN_UNPLUG_ALL_NICS | XEN_UNPLUG_ALL); } EXPORT_SYMBOL_GPL(xen_has_pv_nic_devices); bool xen_has_pv_disk_devices(void) { return __xen_has_pv_device(XEN_UNPLUG_ALL_IDE_DISKS | XEN_UNPLUG_AUX_IDE_DISKS | XEN_UNPLUG_ALL); } EXPORT_SYMBOL_GPL(xen_has_pv_disk_devices); /* * This one is odd - it determines whether you want to run PV _and_ * legacy (IDE) drivers together. This combination is only possible * under HVM. */ bool xen_has_pv_and_legacy_disk_devices(void) { if (!xen_domain()) return false; /* N.B. This is only ever used in HVM mode */ if (xen_pv_domain()) return false; if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY) return true; return false; } EXPORT_SYMBOL_GPL(xen_has_pv_and_legacy_disk_devices); void xen_unplug_emulated_devices(void) { int r; /* user explicitly requested no unplug */ if (xen_emul_unplug & XEN_UNPLUG_NEVER) return; /* check the version of the xen platform PCI device */ r = check_platform_magic(); /* If the version matches enable the Xen platform PCI driver. * Also enable the Xen platform PCI driver if the host does * not support the unplug protocol (XEN_PLATFORM_ERR_MAGIC) * but the user told us that unplugging is unnecessary. */ if (r && !(r == XEN_PLATFORM_ERR_MAGIC && (xen_emul_unplug & XEN_UNPLUG_UNNECESSARY))) return; /* Set the default value of xen_emul_unplug depending on whether or * not the Xen PV frontends and the Xen platform PCI driver have * been compiled for this kernel (modules or built-in are both OK). */ if (!xen_emul_unplug) { if (xen_must_unplug_nics()) { printk(KERN_INFO "Netfront and the Xen platform PCI driver have " "been compiled for this kernel: unplug emulated NICs.\n"); xen_emul_unplug |= XEN_UNPLUG_ALL_NICS; } if (xen_must_unplug_disks()) { printk(KERN_INFO "Blkfront and the Xen platform PCI driver have " "been compiled for this kernel: unplug emulated disks.\n" "You might have to change the root device\n" "from /dev/hd[a-d] to /dev/xvd[a-d]\n" "in your root= kernel command line option\n"); xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS; } } /* Now unplug the emulated devices */ if (!(xen_emul_unplug & XEN_UNPLUG_UNNECESSARY)) outw(xen_emul_unplug, XEN_IOPORT_UNPLUG); xen_platform_pci_unplug = xen_emul_unplug; } static int __init parse_xen_emul_unplug(char *arg) { char *p, *q; int l; for (p = arg; p; p = q) { q = strchr(p, ','); if (q) { l = q - p; q++; } else { l = strlen(p); } if (!strncmp(p, "all", l)) xen_emul_unplug |= XEN_UNPLUG_ALL; else if (!strncmp(p, "ide-disks", l)) xen_emul_unplug |= XEN_UNPLUG_ALL_IDE_DISKS; else if (!strncmp(p, "aux-ide-disks", l)) xen_emul_unplug |= XEN_UNPLUG_AUX_IDE_DISKS; else if (!strncmp(p, "nics", l)) xen_emul_unplug |= XEN_UNPLUG_ALL_NICS; else if (!strncmp(p, "unnecessary", l)) xen_emul_unplug |= XEN_UNPLUG_UNNECESSARY; else if (!strncmp(p, "never", l)) xen_emul_unplug |= XEN_UNPLUG_NEVER; else printk(KERN_WARNING "unrecognised option '%s' " "in parameter 'xen_emul_unplug'\n", p); } return 0; } early_param("xen_emul_unplug", parse_xen_emul_unplug); #endif