[Qemu-devel] [PATCH v2 0/3] xen-platform: disk unplug modifications

[Qemu-devel] [PATCH v2 0/3] xen-platform: disk unplug modifications

[Paul Durrant]

These patches modify the implementation of Xen HVM disk unplug.

Paul Durrant (3):
  xen-platform: re-structure unplug_disks
  xen-platform: add support for unplugging NVMe disks...
  xen-platform: add missing disk unplug option

 hw/i386/xen/xen_platform.c | 50 +++++++++++++++++++++++++++-------------------
 hw/ide/piix.c              |  4 ++--
 include/hw/ide.h           |  2 +-
 3 files changed, 33 insertions(+), 23 deletions(-)

-- 
2.1.4

[Qemu-devel] [PATCH v2 1/3] xen-platform: re-structure unplug_disks

[Paul Durrant]

The current code is poorly structured and potentially leads to multiple
config space reads when one is sufficient. Also the UNPLUG_ALL_IDE_DISKS
flag is mis-named since it also results in SCSI disks being unplugged.

This patch renames the flag and re-structures the code to be more
efficient, and readable.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
---
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>

v2:
- Fix style issue
---
 hw/i386/xen/xen_platform.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
index 2e1e543..f50915f 100644
--- a/hw/i386/xen/xen_platform.c
+++ b/hw/i386/xen/xen_platform.c
@@ -88,7 +88,7 @@ static void log_writeb(PCIXenPlatformState *s, char val)
 }
 
 /* Xen Platform, Fixed IOPort */
-#define UNPLUG_ALL_IDE_DISKS 1
+#define UNPLUG_ALL_DISKS 1
 #define UNPLUG_ALL_NICS 2
 #define UNPLUG_AUX_IDE_DISKS 4
 
@@ -110,14 +110,21 @@ static void pci_unplug_nics(PCIBus *bus)
 static void unplug_disks(PCIBus *b, PCIDevice *d, void *o)
 {
     /* We have to ignore passthrough devices */
-    if (pci_get_word(d->config + PCI_CLASS_DEVICE) ==
-            PCI_CLASS_STORAGE_IDE
-            && strcmp(d->name, "xen-pci-passthrough") != 0) {
+    if (!strcmp(d->name, "xen-pci-passthrough")) {
+        return;
+    }
+
+    switch (pci_get_word(d->config + PCI_CLASS_DEVICE)) {
+    case PCI_CLASS_STORAGE_IDE:
         pci_piix3_xen_ide_unplug(DEVICE(d));
-    } else if (pci_get_word(d->config + PCI_CLASS_DEVICE) ==
-            PCI_CLASS_STORAGE_SCSI
-            && strcmp(d->name, "xen-pci-passthrough") != 0) {
+        break;
+
+    case PCI_CLASS_STORAGE_SCSI:
         object_unparent(OBJECT(d));
+        break;
+
+    default:
+        break;
     }
 }
 
@@ -134,9 +141,9 @@ static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t v
     case 0: {
         PCIDevice *pci_dev = PCI_DEVICE(s);
         /* Unplug devices.  Value is a bitmask of which devices to
-           unplug, with bit 0 the IDE devices, bit 1 the network
+           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_IDE_DISKS) {
+        if (val & UNPLUG_ALL_DISKS) {
             DPRINTF("unplug disks\n");
             pci_unplug_disks(pci_dev->bus);
         }
-- 
2.1.4

Re: [Qemu-devel] [PATCH v2 1/3] xen-platform: re-structure unplug_disks

[Stefano Stabellini]

On Tue, 24 Jan 2017, Paul Durrant wrote:
> The current code is poorly structured and potentially leads to multiple
> config space reads when one is sufficient. Also the UNPLUG_ALL_IDE_DISKS
> flag is mis-named since it also results in SCSI disks being unplugged.
> 
> This patch renames the flag and re-structures the code to be more
> efficient, and readable.
> 
> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

Reviewed-by: Stefano 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>
> 
> v2:
> - Fix style issue
> ---
>  hw/i386/xen/xen_platform.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> index 2e1e543..f50915f 100644
> --- a/hw/i386/xen/xen_platform.c
> +++ b/hw/i386/xen/xen_platform.c
> @@ -88,7 +88,7 @@ static void log_writeb(PCIXenPlatformState *s, char val)
>  }
>  
>  /* Xen Platform, Fixed IOPort */
> -#define UNPLUG_ALL_IDE_DISKS 1
> +#define UNPLUG_ALL_DISKS 1
>  #define UNPLUG_ALL_NICS 2
>  #define UNPLUG_AUX_IDE_DISKS 4
>  
> @@ -110,14 +110,21 @@ static void pci_unplug_nics(PCIBus *bus)
>  static void unplug_disks(PCIBus *b, PCIDevice *d, void *o)
>  {
>      /* We have to ignore passthrough devices */
> -    if (pci_get_word(d->config + PCI_CLASS_DEVICE) ==
> -            PCI_CLASS_STORAGE_IDE
> -            && strcmp(d->name, "xen-pci-passthrough") != 0) {
> +    if (!strcmp(d->name, "xen-pci-passthrough")) {
> +        return;
> +    }
> +
> +    switch (pci_get_word(d->config + PCI_CLASS_DEVICE)) {
> +    case PCI_CLASS_STORAGE_IDE:
>          pci_piix3_xen_ide_unplug(DEVICE(d));
> -    } else if (pci_get_word(d->config + PCI_CLASS_DEVICE) ==
> -            PCI_CLASS_STORAGE_SCSI
> -            && strcmp(d->name, "xen-pci-passthrough") != 0) {
> +        break;
> +
> +    case PCI_CLASS_STORAGE_SCSI:
>          object_unparent(OBJECT(d));
> +        break;
> +
> +    default:
> +        break;
>      }
>  }
>  
> @@ -134,9 +141,9 @@ static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t v
>      case 0: {
>          PCIDevice *pci_dev = PCI_DEVICE(s);
>          /* Unplug devices.  Value is a bitmask of which devices to
> -           unplug, with bit 0 the IDE devices, bit 1 the network
> +           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_IDE_DISKS) {
> +        if (val & UNPLUG_ALL_DISKS) {
>              DPRINTF("unplug disks\n");
>              pci_unplug_disks(pci_dev->bus);
>          }
> -- 
> 2.1.4
> 

[Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Paul Durrant]

...not just IDE and SCSI.

This patch allows the Xen tool-stack to fully support of NVMe as an
emulated disk type.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
---
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
---
 hw/i386/xen/xen_platform.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
index f50915f..7d41ebb 100644
--- a/hw/i386/xen/xen_platform.c
+++ b/hw/i386/xen/xen_platform.c
@@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d, void *o)
         break;
 
     case PCI_CLASS_STORAGE_SCSI:
+    case PCI_CLASS_STORAGE_EXPRESS:
         object_unparent(OBJECT(d));
         break;
 
-- 
2.1.4

Re: [Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Stefano Stabellini]

On Tue, 24 Jan 2017, Paul Durrant wrote:
> ...not just IDE and SCSI.
> 
> This patch allows the Xen tool-stack to fully support of NVMe as an
> emulated disk type.
> 
> Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

Please update docs/misc/hvm-emulated-unplug.markdown in the Xen
repository first. It might be also worth clarifying that `1` actually
means all disks, not just IDE disks. Then, please add a reference to
that commit in the description of this patch.


> ---
> Cc: Stefano Stabellini <sstabellini@kernel.org>
> Cc: Anthony Perard <anthony.perard@citrix.com>
> Cc: "Michael S. Tsirkin" <mst@redhat.com>
> Cc: Paolo Bonzini <pbonzini@redhat.com>
> Cc: Richard Henderson <rth@twiddle.net>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> ---
>  hw/i386/xen/xen_platform.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> index f50915f..7d41ebb 100644
> --- a/hw/i386/xen/xen_platform.c
> +++ b/hw/i386/xen/xen_platform.c
> @@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d, void *o)
>          break;
>  
>      case PCI_CLASS_STORAGE_SCSI:
> +    case PCI_CLASS_STORAGE_EXPRESS:
>          object_unparent(OBJECT(d));
>          break;
>  
> -- 
> 2.1.4
> 

Re: [Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Paul Durrant]

> -----Original Message-----
> From: Stefano Stabellini [mailto:sstabellini@kernel.org]
> Sent: 24 January 2017 23:49
> To: Paul Durrant <Paul.Durrant@citrix.com>
> Cc: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org; Stefano
> Stabellini <sstabellini@kernel.org>; Anthony Perard
> <anthony.perard@citrix.com>; Michael S. Tsirkin <mst@redhat.com>; Paolo
> Bonzini <pbonzini@redhat.com>; Richard Henderson <rth@twiddle.net>;
> Eduardo Habkost <ehabkost@redhat.com>; olaf@aepfle.de
> Subject: Re: [PATCH v2 2/3] xen-platform: add support for unplugging NVMe
> disks...
> 
> On Tue, 24 Jan 2017, Paul Durrant wrote:
> > ...not just IDE and SCSI.
> >
> > This patch allows the Xen tool-stack to fully support of NVMe as an
> > emulated disk type.
> >
> > Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> 
> Please update docs/misc/hvm-emulated-unplug.markdown in the Xen
> repository first. It might be also worth clarifying that `1` actually
> means all disks, not just IDE disks. Then, please add a reference to
> that commit in the description of this patch.
>

Patch posted to remove 'IDE' from the documentation for value '1'. Awaiting ack.

  Paul 
 
> 
> > ---
> > Cc: Stefano Stabellini <sstabellini@kernel.org>
> > Cc: Anthony Perard <anthony.perard@citrix.com>
> > Cc: "Michael S. Tsirkin" <mst@redhat.com>
> > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > Cc: Richard Henderson <rth@twiddle.net>
> > Cc: Eduardo Habkost <ehabkost@redhat.com>
> > ---
> >  hw/i386/xen/xen_platform.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> > index f50915f..7d41ebb 100644
> > --- a/hw/i386/xen/xen_platform.c
> > +++ b/hw/i386/xen/xen_platform.c
> > @@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d,
> void *o)
> >          break;
> >
> >      case PCI_CLASS_STORAGE_SCSI:
> > +    case PCI_CLASS_STORAGE_EXPRESS:
> >          object_unparent(OBJECT(d));
> >          break;
> >
> > --
> > 2.1.4
> >

Re: [Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Stefano Stabellini]

On Wed, 25 Jan 2017, Paul Durrant wrote:
> > -----Original Message-----
> > From: Stefano Stabellini [mailto:sstabellini@kernel.org]
> > Sent: 24 January 2017 23:49
> > To: Paul Durrant <Paul.Durrant@citrix.com>
> > Cc: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org; Stefano
> > Stabellini <sstabellini@kernel.org>; Anthony Perard
> > <anthony.perard@citrix.com>; Michael S. Tsirkin <mst@redhat.com>; Paolo
> > Bonzini <pbonzini@redhat.com>; Richard Henderson <rth@twiddle.net>;
> > Eduardo Habkost <ehabkost@redhat.com>; olaf@aepfle.de
> > Subject: Re: [PATCH v2 2/3] xen-platform: add support for unplugging NVMe
> > disks...
> > 
> > On Tue, 24 Jan 2017, Paul Durrant wrote:
> > > ...not just IDE and SCSI.
> > >
> > > This patch allows the Xen tool-stack to fully support of NVMe as an
> > > emulated disk type.
> > >
> > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> > 
> > Please update docs/misc/hvm-emulated-unplug.markdown in the Xen
> > repository first. It might be also worth clarifying that `1` actually
> > means all disks, not just IDE disks. Then, please add a reference to
> > that commit in the description of this patch.
> >
> 
> Patch posted to remove 'IDE' from the documentation for value '1'. Awaiting ack.

Done.

When you repost this patch, could you also add to the description a
reference to the commit that enables NVMe in QEMU with Xen? I guess it
is a libxl commit?


> > > ---
> > > Cc: Stefano Stabellini <sstabellini@kernel.org>
> > > Cc: Anthony Perard <anthony.perard@citrix.com>
> > > Cc: "Michael S. Tsirkin" <mst@redhat.com>
> > > Cc: Paolo Bonzini <pbonzini@redhat.com>
> > > Cc: Richard Henderson <rth@twiddle.net>
> > > Cc: Eduardo Habkost <ehabkost@redhat.com>
> > > ---
> > >  hw/i386/xen/xen_platform.c | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> > > index f50915f..7d41ebb 100644
> > > --- a/hw/i386/xen/xen_platform.c
> > > +++ b/hw/i386/xen/xen_platform.c
> > > @@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d,
> > void *o)
> > >          break;
> > >
> > >      case PCI_CLASS_STORAGE_SCSI:
> > > +    case PCI_CLASS_STORAGE_EXPRESS:
> > >          object_unparent(OBJECT(d));
> > >          break;
> > >
> > > --
> > > 2.1.4
> > >
> 

[Qemu-devel] [PATCH v2 3/3] xen-platform: add missing disk unplug option

[Paul Durrant]

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: Paul Durrant <paul.durrant@citrix.com>
----
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>
---
 hw/i386/xen/xen_platform.c | 27 +++++++++++++++------------
 hw/ide/piix.c              |  4 ++--
 include/hw/ide.h           |  2 +-
 3 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
index 7d41ebb..6010f35 100644
--- a/hw/i386/xen/xen_platform.c
+++ b/hw/i386/xen/xen_platform.c
@@ -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:
-        object_unparent(OBJECT(d));
+        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);
diff --git a/hw/ide/piix.c b/hw/ide/piix.c
index d5777fd..7e2d767 100644
--- a/hw/ide/piix.c
+++ b/hw/ide/piix.c
@@ -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);
diff --git a/include/hw/ide.h b/include/hw/ide.h
index bc8bd32..3ae087c 100644
--- a/include/hw/ide.h
+++ b/include/hw/ide.h
@@ -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 */
-- 
2.1.4

Re: [Qemu-devel] [PATCH v2 3/3] xen-platform: add missing disk unplug option

[Stefano Stabellini]

On Tue, 24 Jan 2017, Paul Durrant wrote:
> 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: Paul Durrant <paul.durrant@citrix.com>

Reviewed-by: Stefano 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>
> ---
>  hw/i386/xen/xen_platform.c | 27 +++++++++++++++------------
>  hw/ide/piix.c              |  4 ++--
>  include/hw/ide.h           |  2 +-
>  3 files changed, 18 insertions(+), 15 deletions(-)
> 
> diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> index 7d41ebb..6010f35 100644
> --- a/hw/i386/xen/xen_platform.c
> +++ b/hw/i386/xen/xen_platform.c
> @@ -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:
> -        object_unparent(OBJECT(d));
> +        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);
> diff --git a/hw/ide/piix.c b/hw/ide/piix.c
> index d5777fd..7e2d767 100644
> --- a/hw/ide/piix.c
> +++ b/hw/ide/piix.c
> @@ -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);
> diff --git a/include/hw/ide.h b/include/hw/ide.h
> index bc8bd32..3ae087c 100644
> --- a/include/hw/ide.h
> +++ b/include/hw/ide.h
> @@ -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 */
> -- 
> 2.1.4
> 

Re: [Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Paul Durrant]

On 25 January 2017, at 17:54, Stefano Stabellini <sstabellini@kernel.org> wrote:

>
>
>On Wed, 25 Jan 2017, Paul Durrant wrote:
>> > -----Original Message-----
>> > From: Stefano Stabellini [mailto:sstabellini@kernel.org]
>> > Sent: 24 January 2017 23:49
>> > To: Paul Durrant <Paul.Durrant@citrix.com>
>> > Cc: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org; Stefano
>> > Stabellini <sstabellini@kernel.org>; Anthony Perard
>> > <anthony.perard@citrix.com>; Michael S. Tsirkin <mst@redhat.com>; Paolo
>> > Bonzini <pbonzini@redhat.com>; Richard Henderson <rth@twiddle.net>;
>> > Eduardo Habkost <ehabkost@redhat.com>; olaf@aepfle.de
>> > Subject: Re: [PATCH v2 2/3] xen-platform: add support for unplugging NVMe
>> > disks...
>> >
>> > On Tue, 24 Jan 2017, Paul Durrant wrote:
>> > > ...not just IDE and SCSI.
>> > >
>> > > This patch allows the Xen tool-stack to fully support of NVMe as an
>> > > emulated disk type.
>> > >
>> > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
>> >
>> > Please update docs/misc/hvm-emulated-unplug.markdown in the Xen
>> > repository first. It might be also worth clarifying that `1` actually
>> > means all disks, not just IDE disks. Then, please add a reference to
>> > that commit in the description of this patch.
>> >
>>
>> Patch posted to remove 'IDE' from the documentation for value '1'. Awaiting ack.
>Done.
>When you repost this patch, could you also add to the description a
>reference to the commit that enables NVMe in QEMU with Xen? I guess it
>is a libxl commit?

I think there is a chicken and egg issue here. Wei wanted to ensure that QEMU is able to unplug NVMe drives before accepting my patch to libxl.

  Paul

>> > > ---
>> > > Cc: Stefano Stabellini <sstabellini@kernel.org>
>> > > Cc: Anthony Perard <anthony.perard@citrix.com>
>> > > Cc: "Michael S. Tsirkin" <mst@redhat.com>
>> > > Cc: Paolo Bonzini <pbonzini@redhat.com>
>> > > Cc: Richard Henderson <rth@twiddle.net>
>> > > Cc: Eduardo Habkost <ehabkost@redhat.com>
>> > > ---
>> > >  hw/i386/xen/xen_platform.c | 1 +
>> > >  1 file changed, 1 insertion(+)
>> > >
>> > > diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
>> > > index f50915f..7d41ebb 100644
>> > > --- a/hw/i386/xen/xen_platform.c
>> > > +++ b/hw/i386/xen/xen_platform.c
>> > > @@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d,
>> > void *o)
>> > >          break;
>> > >
>> > >      case PCI_CLASS_STORAGE_SCSI:
>> > > +    case PCI_CLASS_STORAGE_EXPRESS:
>> > >          object_unparent(OBJECT(d));
>> > >          break;
>> > >
>> > > --
>> > > 2.1.4
>> > >
>>
>

Re: [Qemu-devel] [PATCH v2 2/3] xen-platform: add support for unplugging NVMe disks...

[Stefano Stabellini]

On Wed, 25 Jan 2017, Paul Durrant wrote:
> On 25 January 2017, at 17:54, Stefano Stabellini <sstabellini@kernel.org> wrote:
> 
> >
> >
> >On Wed, 25 Jan 2017, Paul Durrant wrote:
> >> > -----Original Message-----
> >> > From: Stefano Stabellini [mailto:sstabellini@kernel.org]
> >> > Sent: 24 January 2017 23:49
> >> > To: Paul Durrant <Paul.Durrant@citrix.com>
> >> > Cc: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org; Stefano
> >> > Stabellini <sstabellini@kernel.org>; Anthony Perard
> >> > <anthony.perard@citrix.com>; Michael S. Tsirkin <mst@redhat.com>; Paolo
> >> > Bonzini <pbonzini@redhat.com>; Richard Henderson <rth@twiddle.net>;
> >> > Eduardo Habkost <ehabkost@redhat.com>; olaf@aepfle.de
> >> > Subject: Re: [PATCH v2 2/3] xen-platform: add support for unplugging NVMe
> >> > disks...
> >> >
> >> > On Tue, 24 Jan 2017, Paul Durrant wrote:
> >> > > ...not just IDE and SCSI.
> >> > >
> >> > > This patch allows the Xen tool-stack to fully support of NVMe as an
> >> > > emulated disk type.
> >> > >
> >> > > Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
> >> >
> >> > Please update docs/misc/hvm-emulated-unplug.markdown in the Xen
> >> > repository first. It might be also worth clarifying that `1` actually
> >> > means all disks, not just IDE disks. Then, please add a reference to
> >> > that commit in the description of this patch.
> >> >
> >>
> >> Patch posted to remove 'IDE' from the documentation for value '1'. Awaiting ack.
> >Done.
> >When you repost this patch, could you also add to the description a
> >reference to the commit that enables NVMe in QEMU with Xen? I guess it
> >is a libxl commit?
> 
> I think there is a chicken and egg issue here. Wei wanted to ensure that QEMU is able to unplug
> NVMe drives before accepting my patch to libxl.

No problems. In that case, please add a link to the xen-devel email
thread.


> >> > > ---
> >> > > Cc: Stefano Stabellini <sstabellini@kernel.org>
> >> > > Cc: Anthony Perard <anthony.perard@citrix.com>
> >> > > Cc: "Michael S. Tsirkin" <mst@redhat.com>
> >> > > Cc: Paolo Bonzini <pbonzini@redhat.com>
> >> > > Cc: Richard Henderson <rth@twiddle.net>
> >> > > Cc: Eduardo Habkost <ehabkost@redhat.com>
> >> > > ---
> >> > >  hw/i386/xen/xen_platform.c | 1 +
> >> > >  1 file changed, 1 insertion(+)
> >> > >
> >> > > diff --git a/hw/i386/xen/xen_platform.c b/hw/i386/xen/xen_platform.c
> >> > > index f50915f..7d41ebb 100644
> >> > > --- a/hw/i386/xen/xen_platform.c
> >> > > +++ b/hw/i386/xen/xen_platform.c
> >> > > @@ -120,6 +120,7 @@ static void unplug_disks(PCIBus *b, PCIDevice *d,
> >> > void *o)
> >> > >          break;
> >> > >
> >> > >      case PCI_CLASS_STORAGE_SCSI:
> >> > > +    case PCI_CLASS_STORAGE_EXPRESS:
> >> > >          object_unparent(OBJECT(d));
> >> > >          break;
> >> > >
> >> > > --
> >> > > 2.1.4
> >> > >
> >>
> >
> 
> 
>