From c1c5413ad58cb73267d328e6020268aa2e50d8ca Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Fri, 14 May 2010 12:44:30 +0100 Subject: x86: Unplug emulated disks and nics. Add a xen_emul_unplug command line option to the kernel to unplug xen emulated disks and nics. 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). The user can specify xen_emul_unplug=ignore to enable PV drivers on HVM even if the host platform doesn't support unplug. Signed-off-by: Stefano Stabellini Signed-off-by: Jeremy Fitzhardinge diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 82d6aeb..eefcd80 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -115,6 +115,7 @@ parameter is applicable: More X86-64 boot options can be found in Documentation/x86/x86_64/boot-options.txt . X86 Either 32bit or 64bit x86 (same as X86-32+X86-64) + XEN Xen support is enabled In addition, the following text indicates that the option: @@ -2879,6 +2880,16 @@ and is between 256 and 4096 characters. It is defined in the file xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks. xd_geo= See header of drivers/block/xd.c. + xen_emul_unplug= [HW,X86,XEN] + Unplug Xen emulated devices + Format: [unplug0,][unplug1] + ide-disks -- unplug primary master IDE devices + aux-ide-disks -- unplug non-primary-master IDE devices + nics -- unplug network devices + all -- unplug all emulated devices (NICs and IDE disks) + ignore -- continue loading the Xen platform PCI driver even + if the version check failed + xirc2ps_cs= [NET,PCMCIA] Format: ,,,,,[,[,[,]]] diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index 3bb4fc2..9309546 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -12,7 +12,7 @@ CFLAGS_mmu.o := $(nostackp) obj-y := enlighten.o setup.o multicalls.o mmu.o irq.o \ time.o xen-asm.o xen-asm_$(BITS).o \ - grant-table.o suspend.o + grant-table.o suspend.o platform-pci-unplug.o obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index a901729..157c93b 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1314,6 +1314,7 @@ static void __init xen_hvm_guest_init(void) if (xen_feature(XENFEAT_hvm_callback_vector)) xen_have_vector_callback = 1; register_cpu_notifier(&xen_hvm_cpu_notifier); + xen_unplug_emulated_devices(); have_vcpu_info_placement = 0; x86_init.irqs.intr_init = xen_init_IRQ; xen_hvm_init_time_ops(); diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c new file mode 100644 index 0000000..2f7f3fb --- /dev/null +++ b/arch/x86/xen/platform-pci-unplug.c @@ -0,0 +1,135 @@ +/****************************************************************************** + * 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 + +#define XEN_PLATFORM_ERR_MAGIC -1 +#define XEN_PLATFORM_ERR_PROTOCOL -2 +#define XEN_PLATFORM_ERR_BLACKLIST -3 + +/* store the value of xen_emul_unplug after the unplug is done */ +int xen_platform_pci_unplug; +EXPORT_SYMBOL_GPL(xen_platform_pci_unplug); +static int xen_emul_unplug; + +static int __init 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; +} + +void __init xen_unplug_emulated_devices(void) +{ + int r; + + /* 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 version is really old + * and the user told us to ignore it. */ + if (r && !(r == XEN_PLATFORM_ERR_MAGIC && + (xen_emul_unplug & XEN_UNPLUG_IGNORE))) + 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_IGNORE)) + 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, "ignore", l)) + xen_emul_unplug |= XEN_UNPLUG_IGNORE; + 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); diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 089d189..ed77694 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -40,6 +40,7 @@ void xen_vcpu_restore(void); void xen_callback_vector(void); void xen_hvm_init_shared_info(void); +void __init xen_unplug_emulated_devices(void); void __init xen_build_dynamic_phys_to_machine(void); diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c index 82ed403..6eb2989 100644 --- a/drivers/block/xen-blkfront.c +++ b/drivers/block/xen-blkfront.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include @@ -737,6 +738,22 @@ static int blkfront_probe(struct xenbus_device *dev, } } + /* no unplug has been done: do not hook devices != xen vbds */ + if (xen_hvm_domain() && (xen_platform_pci_unplug & XEN_UNPLUG_IGNORE)) { + int major; + + if (!VDEV_IS_EXTENDED(vdevice)) + major = BLKIF_MAJOR(vdevice); + else + major = XENVBD_MAJOR; + + if (major != XENVBD_MAJOR) { + printk(KERN_INFO + "%s: HVM does not support vbd %d as xen block device\n", + __FUNCTION__, vdevice); + return -ENODEV; + } + } info = kzalloc(sizeof(*info), GFP_KERNEL); if (!info) { xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure"); diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c index bdb44f2..c01b5dd 100644 --- a/drivers/xen/platform-pci.c +++ b/drivers/xen/platform-pci.c @@ -27,6 +27,7 @@ #include #include +#include #include #include #include @@ -195,6 +196,11 @@ static struct pci_driver platform_driver = { static int __init platform_pci_module_init(void) { + /* no unplug has been done, IGNORE hasn't been specified: just + * return now */ + if (!xen_platform_pci_unplug) + return -ENODEV; + return pci_register_driver(&platform_driver); } diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index a9e83c4..37e8894 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -56,6 +56,7 @@ #include #include +#include #include #include "xenbus_comms.h" @@ -977,6 +978,9 @@ static void wait_for_devices(struct xenbus_driver *xendrv) #ifndef MODULE static int __init boot_wait_for_devices(void) { + if (xen_hvm_domain() && !xen_platform_pci_unplug) + return -ENODEV; + ready_to_wait_for_devices = 1; wait_for_devices(NULL); return 0; diff --git a/include/xen/platform_pci.h b/include/xen/platform_pci.h new file mode 100644 index 0000000..ce9d671 --- /dev/null +++ b/include/xen/platform_pci.h @@ -0,0 +1,49 @@ +#ifndef _XEN_PLATFORM_PCI_H +#define _XEN_PLATFORM_PCI_H + +#define XEN_IOPORT_MAGIC_VAL 0x49d2 +#define XEN_IOPORT_LINUX_PRODNUM 0x0003 +#define XEN_IOPORT_LINUX_DRVVER 0x0001 + +#define XEN_IOPORT_BASE 0x10 + +#define XEN_IOPORT_PLATFLAGS (XEN_IOPORT_BASE + 0) /* 1 byte access (R/W) */ +#define XEN_IOPORT_MAGIC (XEN_IOPORT_BASE + 0) /* 2 byte access (R) */ +#define XEN_IOPORT_UNPLUG (XEN_IOPORT_BASE + 0) /* 2 byte access (W) */ +#define XEN_IOPORT_DRVVER (XEN_IOPORT_BASE + 0) /* 4 byte access (W) */ + +#define XEN_IOPORT_SYSLOG (XEN_IOPORT_BASE + 2) /* 1 byte access (W) */ +#define XEN_IOPORT_PROTOVER (XEN_IOPORT_BASE + 2) /* 1 byte access (R) */ +#define XEN_IOPORT_PRODNUM (XEN_IOPORT_BASE + 2) /* 2 byte access (W) */ + +#define XEN_UNPLUG_ALL_IDE_DISKS 1 +#define XEN_UNPLUG_ALL_NICS 2 +#define XEN_UNPLUG_AUX_IDE_DISKS 4 +#define XEN_UNPLUG_ALL 7 +#define XEN_UNPLUG_IGNORE 8 + +static inline int xen_must_unplug_nics(void) { +#if (defined(CONFIG_XEN_NETDEV_FRONTEND) || \ + defined(CONFIG_XEN_NETDEV_FRONTEND_MODULE)) && \ + (defined(CONFIG_XEN_PLATFORM_PCI) || \ + defined(CONFIG_XEN_PLATFORM_PCI_MODULE)) + return 1; +#else + return 0; +#endif +} + +static inline int xen_must_unplug_disks(void) { +#if (defined(CONFIG_XEN_BLKDEV_FRONTEND) || \ + defined(CONFIG_XEN_BLKDEV_FRONTEND_MODULE)) && \ + (defined(CONFIG_XEN_PLATFORM_PCI) || \ + defined(CONFIG_XEN_PLATFORM_PCI_MODULE)) + return 1; +#else + return 0; +#endif +} + +extern int xen_platform_pci_unplug; + +#endif /* _XEN_PLATFORM_PCI_H */ -- cgit v0.10.2