Commit ae4d2eb2 authored by Paul Durrant's avatar Paul Durrant Committed by Stefano Stabellini
Browse files

xen-platform: add missing disk unplug option 

The Xen HVM unplug protocol [1] specifies a mechanism to allow guests to
request unplug of 'aux' disks (which is stated to mean all IDE disks,
except the primary master). This patch adds support for that unplug request.

NOTE: The semantics of what happens if unplug of all disks and 'aux' disks
      is simultaneously requests is not clear. The patch makes that
      assumption that an 'all' request overrides an 'aux' request.

[1] http://xenbits.xen.org/gitweb/?p=xen.git;a=blob;f=docs/misc/hvm-emulated-unplug.markdown



Signed-off-by: default avatarPaul Durrant <paul.durrant@citrix.com>
Reviewed-by: default avatarStefano Stabellini <sstabellini@kernel.org>
----
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: John Snow <jsnow@redhat.com>
parent 090fa1c8

hw/i386/xen/xen_platform.c

+15 −12
Original line number Diff line number Diff line
@@ -107,8 +107,12 @@ static void pci_unplug_nics(PCIBus *bus) 
    pci_for_each_device(bus, 0, unplug_nic, NULL);

}



static void unplug_disks(PCIBus *b, PCIDevice *d, void *o)

static void unplug_disks(PCIBus *b, PCIDevice *d, void *opaque)

{

    uint32_t flags = *(uint32_t *)opaque;

    bool aux = (flags & UNPLUG_AUX_IDE_DISKS) &&

        !(flags & UNPLUG_ALL_DISKS);



    /* We have to ignore passthrough devices */

    if (!strcmp(d->name, "xen-pci-passthrough")) {

        return;
@@ -116,12 +120,14 @@ static void unplug_disks(PCIBus *b, PCIDevice *d, void *o) 


    switch (pci_get_word(d->config + PCI_CLASS_DEVICE)) {

    case PCI_CLASS_STORAGE_IDE:

        pci_piix3_xen_ide_unplug(DEVICE(d));

        pci_piix3_xen_ide_unplug(DEVICE(d), aux);

        break;



    case PCI_CLASS_STORAGE_SCSI:

    case PCI_CLASS_STORAGE_EXPRESS:

        if (!aux) {

            object_unparent(OBJECT(d));

        }

        break;



    default:
@@ -129,9 +135,9 @@ static void unplug_disks(PCIBus *b, PCIDevice *d, void *o) 
    }

}



static void pci_unplug_disks(PCIBus *bus)

static void pci_unplug_disks(PCIBus *bus, uint32_t flags)

{

    pci_for_each_device(bus, 0, unplug_disks, NULL);

    pci_for_each_device(bus, 0, unplug_disks, &flags);

}



static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t val)
@@ -144,17 +150,14 @@ static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t v 
        /* Unplug devices.  Value is a bitmask of which devices to

           unplug, with bit 0 the disk devices, bit 1 the network

           devices, and bit 2 the non-primary-master IDE devices. */

        if (val & UNPLUG_ALL_DISKS) {

        if (val & (UNPLUG_ALL_DISKS | UNPLUG_AUX_IDE_DISKS)) {

            DPRINTF("unplug disks\n");

            pci_unplug_disks(pci_dev->bus);

            pci_unplug_disks(pci_dev->bus, val);

        }

        if (val & UNPLUG_ALL_NICS) {

            DPRINTF("unplug nics\n");

            pci_unplug_nics(pci_dev->bus);

        }

        if (val & UNPLUG_AUX_IDE_DISKS) {

            DPRINTF("unplug auxiliary disks not supported\n");

        }

        break;

    }

    case 2:
@@ -335,14 +338,14 @@ static void xen_platform_ioport_writeb(void *opaque, hwaddr addr, 
             * If VMDP was to control both disk and LAN it would use 4.

             * If it controlled just disk or just LAN, it would use 8 below.

             */

            pci_unplug_disks(pci_dev->bus);

            pci_unplug_disks(pci_dev->bus, UNPLUG_ALL_DISKS);

            pci_unplug_nics(pci_dev->bus);

        }

        break;

    case 8:

        switch (val) {

        case 1:

            pci_unplug_disks(pci_dev->bus);

            pci_unplug_disks(pci_dev->bus, UNPLUG_ALL_DISKS);

            break;

        case 2:

            pci_unplug_nics(pci_dev->bus);

hw/ide/piix.c

+2 −2
Original line number Diff line number Diff line
@@ -165,7 +165,7 @@ static void pci_piix_ide_realize(PCIDevice *dev, Error **errp) 
    pci_piix_init_ports(d);

}



int pci_piix3_xen_ide_unplug(DeviceState *dev)

int pci_piix3_xen_ide_unplug(DeviceState *dev, bool aux)

{

    PCIIDEState *pci_ide;

    DriveInfo *di;
@@ -174,7 +174,7 @@ int pci_piix3_xen_ide_unplug(DeviceState *dev) 


    pci_ide = PCI_IDE(dev);



    for (i = 0; i < 4; i++) {

    for (i = aux ? 1 : 0; i < 4; i++) {

        di = drive_get_by_index(IF_IDE, i);

        if (di != NULL && !di->media_cd) {

            BlockBackend *blk = blk_by_legacy_dinfo(di);

include/hw/ide.h

+1 −1
Original line number Diff line number Diff line
@@ -17,7 +17,7 @@ void pci_cmd646_ide_init(PCIBus *bus, DriveInfo **hd_table, 
PCIDevice *pci_piix3_xen_ide_init(PCIBus *bus, DriveInfo **hd_table, int devfn);

PCIDevice *pci_piix3_ide_init(PCIBus *bus, DriveInfo **hd_table, int devfn);

PCIDevice *pci_piix4_ide_init(PCIBus *bus, DriveInfo **hd_table, int devfn);

int pci_piix3_xen_ide_unplug(DeviceState *dev);

int pci_piix3_xen_ide_unplug(DeviceState *dev, bool aux);

void vt82c686b_ide_init(PCIBus *bus, DriveInfo **hd_table, int devfn);



/* ide-mmio.c */