xen: pvhvm: rename xen_emul_unplug=ignore to =unnnecessary

It is not immediately clear what this option causes to become
ignored. The actual meaning is that it is not necessary to unplug the
emulated devices to safely use the PV ones, even if the platform does
not support the unplug protocol. (pressumably the user will only add
this option if they have ensured that their domain configuration is
safe).

I think xen_emul_unplug=unnecessary better captures this.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 8bbe83b9d0b29411ef0a3746e06cb4da97f9d833..f084af0cb8e01f7a67026367508fef1085bc801b 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2629,8 +2629,9 @@ and is between 256 and 4096 characters. It is defined in the file
                        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
+                       unnecessary -- unplugging emulated devices is
+                               unnecessary even if the host did not respond to
+                               the unplug protocol
                        never -- do not unplug even if version check succeeds
 
        xirc2ps_cs=     [NET,PCMCIA]

diff --git a/arch/x86/xen/platform-pci-unplug.c b/arch/x86/xen/platform-pci-unplug.c
index 070dfa0654bdcbf7ee882589db68ce9b69ad17ae..0f456386cce5dc3a0c08ed45bfaf0a268be25819 100644 (file)
--- a/arch/x86/xen/platform-pci-unplug.c
+++ b/arch/x86/xen/platform-pci-unplug.c
@@ -78,10 +78,11 @@ void __init xen_unplug_emulated_devices(void)
        /* 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. */
+        * 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_IGNORE)))
+                       (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
@@ -102,7 +103,7 @@ void __init xen_unplug_emulated_devices(void)
                }
        }
        /* Now unplug the emulated devices */
-       if (!(xen_emul_unplug & XEN_UNPLUG_IGNORE))
+       if (!(xen_emul_unplug & XEN_UNPLUG_UNNECESSARY))
                outw(xen_emul_unplug, XEN_IOPORT_UNPLUG);
        xen_platform_pci_unplug = xen_emul_unplug;
 }
@@ -128,8 +129,8 @@ static int __init parse_xen_emul_unplug(char *arg)
                        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 if (!strncmp(p, "unnecessary", l))
+                       xen_emul_unplug |= XEN_UNPLUG_UNNECESSARY;
                else if (!strncmp(p, "never", l))
                        xen_emul_unplug |= XEN_UNPLUG_NEVER;
                else

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index ac1b682edecb362831eb32e7fd09faaff69da428..ab735a605cf3f23e0f516b21ae07f0d6c5e7e914 100644 (file)
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -834,7 +834,7 @@ static int blkfront_probe(struct xenbus_device *dev,
                char *type;
                int len;
                /* no unplug has been done: do not hook devices != xen vbds */
-               if (xen_platform_pci_unplug & XEN_UNPLUG_IGNORE) {
+               if (xen_platform_pci_unplug & XEN_UNPLUG_UNNECESSARY) {
                        int major;
 
                        if (!VDEV_IS_EXTENDED(vdevice))

diff --git a/include/xen/platform_pci.h b/include/xen/platform_pci.h
index 123b7752fa6a0e590583b782c53eb5b7f7a08c77..590ccfd82645c951908951c24d5f46c111fd8936 100644 (file)
--- a/include/xen/platform_pci.h
+++ b/include/xen/platform_pci.h
@@ -20,7 +20,7 @@
 #define XEN_UNPLUG_ALL_NICS 2
 #define XEN_UNPLUG_AUX_IDE_DISKS 4
 #define XEN_UNPLUG_ALL 7
-#define XEN_UNPLUG_IGNORE 8
+#define XEN_UNPLUG_UNNECESSARY 8
 #define XEN_UNPLUG_NEVER 16
 
 static inline int xen_must_unplug_nics(void) {