1 /******************************************************************************
2 * platform-pci-unplug.c
4 * Xen platform PCI device driver
5 * Copyright (c) 2010, Citrix
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms and conditions of the GNU General Public License,
9 * version 2, as published by the Free Software Foundation.
11 * This program is distributed in the hope it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
16 * You should have received a copy of the GNU General Public License along with
17 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
18 * Place - Suite 330, Boston, MA 02111-1307 USA.
22 #include <linux/init.h>
24 #include <linux/module.h>
26 #include <xen/platform_pci.h>
29 #define XEN_PLATFORM_ERR_MAGIC -1
30 #define XEN_PLATFORM_ERR_PROTOCOL -2
31 #define XEN_PLATFORM_ERR_BLACKLIST -3
33 #ifdef CONFIG_XEN_PVHVM
34 /* store the value of xen_emul_unplug after the unplug is done */
35 static int xen_platform_pci_unplug
;
36 static int xen_emul_unplug
;
38 static int check_platform_magic(void)
43 magic
= inw(XEN_IOPORT_MAGIC
);
44 if (magic
!= XEN_IOPORT_MAGIC_VAL
) {
45 printk(KERN_ERR
"Xen Platform PCI: unrecognised magic value\n");
46 return XEN_PLATFORM_ERR_MAGIC
;
49 protocol
= inb(XEN_IOPORT_PROTOVER
);
51 printk(KERN_DEBUG
"Xen Platform PCI: I/O protocol version %d\n",
56 outw(XEN_IOPORT_LINUX_PRODNUM
, XEN_IOPORT_PRODNUM
);
57 outl(XEN_IOPORT_LINUX_DRVVER
, XEN_IOPORT_DRVVER
);
58 if (inw(XEN_IOPORT_MAGIC
) != XEN_IOPORT_MAGIC_VAL
) {
59 printk(KERN_ERR
"Xen Platform: blacklisted by host\n");
60 return XEN_PLATFORM_ERR_BLACKLIST
;
64 printk(KERN_WARNING
"Xen Platform PCI: unknown I/O protocol version");
65 return XEN_PLATFORM_ERR_PROTOCOL
;
71 bool xen_has_pv_devices(void)
76 /* PV domains always have them. */
80 /* And user has xen_platform_pci=0 set in guest config as
81 * driver did not modify the value. */
82 if (xen_platform_pci_unplug
== 0)
85 if (xen_platform_pci_unplug
& XEN_UNPLUG_NEVER
)
88 if (xen_platform_pci_unplug
& XEN_UNPLUG_ALL
)
91 /* This is an odd one - we are going to run legacy
92 * and PV drivers at the same time. */
93 if (xen_platform_pci_unplug
& XEN_UNPLUG_UNNECESSARY
)
96 /* And the caller has to follow with xen_pv_{disk,nic}_devices
97 * to be certain which driver can load. */
100 EXPORT_SYMBOL_GPL(xen_has_pv_devices
);
102 static bool __xen_has_pv_device(int state
)
104 /* HVM domains might or might not */
105 if (xen_hvm_domain() && (xen_platform_pci_unplug
& state
))
108 return xen_has_pv_devices();
111 bool xen_has_pv_nic_devices(void)
113 return __xen_has_pv_device(XEN_UNPLUG_ALL_NICS
| XEN_UNPLUG_ALL
);
115 EXPORT_SYMBOL_GPL(xen_has_pv_nic_devices
);
117 bool xen_has_pv_disk_devices(void)
119 return __xen_has_pv_device(XEN_UNPLUG_ALL_IDE_DISKS
|
120 XEN_UNPLUG_AUX_IDE_DISKS
| XEN_UNPLUG_ALL
);
122 EXPORT_SYMBOL_GPL(xen_has_pv_disk_devices
);
125 * This one is odd - it determines whether you want to run PV _and_
126 * legacy (IDE) drivers together. This combination is only possible
129 bool xen_has_pv_and_legacy_disk_devices(void)
134 /* N.B. This is only ever used in HVM mode */
138 if (xen_platform_pci_unplug
& XEN_UNPLUG_UNNECESSARY
)
143 EXPORT_SYMBOL_GPL(xen_has_pv_and_legacy_disk_devices
);
145 void xen_unplug_emulated_devices(void)
149 /* user explicitly requested no unplug */
150 if (xen_emul_unplug
& XEN_UNPLUG_NEVER
)
152 /* check the version of the xen platform PCI device */
153 r
= check_platform_magic();
154 /* If the version matches enable the Xen platform PCI driver.
155 * Also enable the Xen platform PCI driver if the host does
156 * not support the unplug protocol (XEN_PLATFORM_ERR_MAGIC)
157 * but the user told us that unplugging is unnecessary. */
158 if (r
&& !(r
== XEN_PLATFORM_ERR_MAGIC
&&
159 (xen_emul_unplug
& XEN_UNPLUG_UNNECESSARY
)))
161 /* Set the default value of xen_emul_unplug depending on whether or
162 * not the Xen PV frontends and the Xen platform PCI driver have
163 * been compiled for this kernel (modules or built-in are both OK). */
164 if (!xen_emul_unplug
) {
165 if (xen_must_unplug_nics()) {
166 printk(KERN_INFO
"Netfront and the Xen platform PCI driver have "
167 "been compiled for this kernel: unplug emulated NICs.\n");
168 xen_emul_unplug
|= XEN_UNPLUG_ALL_NICS
;
170 if (xen_must_unplug_disks()) {
171 printk(KERN_INFO
"Blkfront and the Xen platform PCI driver have "
172 "been compiled for this kernel: unplug emulated disks.\n"
173 "You might have to change the root device\n"
174 "from /dev/hd[a-d] to /dev/xvd[a-d]\n"
175 "in your root= kernel command line option\n");
176 xen_emul_unplug
|= XEN_UNPLUG_ALL_IDE_DISKS
;
179 /* Now unplug the emulated devices */
180 if (!(xen_emul_unplug
& XEN_UNPLUG_UNNECESSARY
))
181 outw(xen_emul_unplug
, XEN_IOPORT_UNPLUG
);
182 xen_platform_pci_unplug
= xen_emul_unplug
;
185 static int __init
parse_xen_emul_unplug(char *arg
)
190 for (p
= arg
; p
; p
= q
) {
198 if (!strncmp(p
, "all", l
))
199 xen_emul_unplug
|= XEN_UNPLUG_ALL
;
200 else if (!strncmp(p
, "ide-disks", l
))
201 xen_emul_unplug
|= XEN_UNPLUG_ALL_IDE_DISKS
;
202 else if (!strncmp(p
, "aux-ide-disks", l
))
203 xen_emul_unplug
|= XEN_UNPLUG_AUX_IDE_DISKS
;
204 else if (!strncmp(p
, "nics", l
))
205 xen_emul_unplug
|= XEN_UNPLUG_ALL_NICS
;
206 else if (!strncmp(p
, "unnecessary", l
))
207 xen_emul_unplug
|= XEN_UNPLUG_UNNECESSARY
;
208 else if (!strncmp(p
, "never", l
))
209 xen_emul_unplug
|= XEN_UNPLUG_NEVER
;
211 printk(KERN_WARNING
"unrecognised option '%s' "
212 "in parameter 'xen_emul_unplug'\n", p
);
216 early_param("xen_emul_unplug", parse_xen_emul_unplug
);