diff mbox

xen: use libxendevice model to restrict operations

Message ID 1489757419-8179-1-git-send-email-paul.durrant@citrix.com (mailing list archive)
State New, archived
Headers show

Commit Message

Paul Durrant March 17, 2017, 1:30 p.m. UTC
This patch adds a command-line option (-xen-domid-restrict) which will
use the new libxendevicemodel API to restrict devicemodel operations to
the specified domid.

This patch also adds a tracepoint to allow successful enabling of the
restriction to be monitored.

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>

NOTE: This is already re-based on Juergen Gross's patch "xen: use 5 digit
      xen versions" and so should not be applied until after that patch
      has been applied.
---
 hw/xen/trace-events         |  1 +
 include/hw/xen/xen.h        |  1 +
 include/hw/xen/xen_common.h | 23 +++++++++++++++++++++++
 qemu-options.hx             |  6 ++++++
 vl.c                        |  8 ++++++++
 xen-hvm.c                   |  8 ++++++++
 6 files changed, 47 insertions(+)

Comments

Philippe Mathieu-Daudé March 17, 2017, 9:21 p.m. UTC | #1
Hi Paul,

On 03/17/2017 10:30 AM, Paul Durrant wrote:
> This patch adds a command-line option (-xen-domid-restrict) which will
> use the new libxendevicemodel API to restrict devicemodel operations to
> the specified domid.
>
> This patch also adds a tracepoint to allow successful enabling of the
> restriction to be monitored.
>
> 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>
>
> NOTE: This is already re-based on Juergen Gross's patch "xen: use 5 digit
>       xen versions" and so should not be applied until after that patch
>       has been applied.
> ---
>  hw/xen/trace-events         |  1 +
>  include/hw/xen/xen.h        |  1 +
>  include/hw/xen/xen_common.h | 23 +++++++++++++++++++++++
>  qemu-options.hx             |  6 ++++++
>  vl.c                        |  8 ++++++++
>  xen-hvm.c                   |  8 ++++++++
>  6 files changed, 47 insertions(+)
>
> diff --git a/hw/xen/trace-events b/hw/xen/trace-events
> index c4fb6f1..a5b5e8b 100644
> --- a/hw/xen/trace-events
> +++ b/hw/xen/trace-events
> @@ -11,3 +11,4 @@ xen_map_portio_range(uint32_t id, uint64_t start_addr, uint64_t end_addr) "id: %
>  xen_unmap_portio_range(uint32_t id, uint64_t start_addr, uint64_t end_addr) "id: %u start: %#"PRIx64" end: %#"PRIx64
>  xen_map_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id: %u bdf: %02x.%02x.%02x"
>  xen_unmap_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id: %u bdf: %02x.%02x.%02x"
> +xen_domid_restrict(void) ""
> diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
> index 2b1733b..7efcdaa 100644
> --- a/include/hw/xen/xen.h
> +++ b/include/hw/xen/xen.h
> @@ -21,6 +21,7 @@ enum xen_mode {
>
>  extern uint32_t xen_domid;
>  extern enum xen_mode xen_mode;
> +extern bool xen_domid_restrict;
>
>  extern bool xen_allowed;
>
> diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
> index df098c7..5962bc4 100644
> --- a/include/hw/xen/xen_common.h
> +++ b/include/hw/xen/xen_common.h
> @@ -152,6 +152,13 @@ static inline int xendevicemodel_set_mem_type(
>      return xc_hvm_set_mem_type(dmod, domid, mem_type, first_pfn, nr);
>  }
>
> +static inline int xendevicemodel_restrict(
> +    xendevicemodel_handle *dmod, domid_t domid)
> +{
> +    errno = ENOTTY;
> +    return -1;
> +}
> +
>  #else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40900 */
>
>  #include <xendevicemodel.h>
> @@ -206,6 +213,22 @@ static inline int xen_modified_memory(domid_t domid, uint64_t first_pfn,
>      return xendevicemodel_modified_memory(xen_dmod, domid, first_pfn, nr);
>  }
>
> +static inline int xen_restrict(domid_t domid)
> +{
> +    int rc = xendevicemodel_restrict(xen_dmod, domid);

might it be more useful to log the retcode?

        trace_xen_domid_restrict(rc);

> +
> +    if (rc == 0) {
> +        trace_xen_domid_restrict();

and drop the previous line.

> +        return 0;
> +    }
> +
> +    if (errno == ENOTTY) {
> +        return 0;
> +    }
> +
> +    return rc;
> +}
> +
>  /* Xen 4.2 through 4.6 */
>  #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40701
>
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 99af8ed..4aab077 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -3354,6 +3354,10 @@ DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
>      "-xen-attach     attach to existing xen domain\n"
>      "                xend will use this when starting QEMU\n",
>      QEMU_ARCH_ALL)
> +DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
> +    "-xen-domid-restrict     restrict set of available xen operations\n"
> +    "                        to specified domain id\n",
> +    QEMU_ARCH_ALL)
>  STEXI
>  @item -xen-domid @var{id}
>  @findex -xen-domid
> @@ -3366,6 +3370,8 @@ Warning: should not be used when xend is in use (XEN only).
>  @findex -xen-attach
>  Attach to existing xen domain.
>  xend will use this when starting QEMU (XEN only).
> +@findex -xen-domid-restrict
> +Restrict set of available xen operations to specified domain id (XEN only).
>  ETEXI
>
>  DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
> diff --git a/vl.c b/vl.c
> index 0b4ed52..f46e070 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -205,6 +205,7 @@ static NotifierList machine_init_done_notifiers =
>  bool xen_allowed;
>  uint32_t xen_domid;
>  enum xen_mode xen_mode = XEN_EMULATE;
> +bool xen_domid_restrict;
>
>  static int has_defaults = 1;
>  static int default_serial = 1;
> @@ -3933,6 +3934,13 @@ int main(int argc, char **argv, char **envp)
>                  }
>                  xen_mode = XEN_ATTACH;
>                  break;
> +            case QEMU_OPTION_xen_domid_restrict:
> +                if (!(xen_available())) {
> +                    error_report("Option not supported for this target");
> +                    exit(1);
> +                }
> +                xen_domid_restrict = true;
> +                break;
>              case QEMU_OPTION_trace:
>                  g_free(trace_file);
>                  trace_file = trace_opt_parse(optarg);
> diff --git a/xen-hvm.c b/xen-hvm.c
> index 4b928cf..335e263 100644
> --- a/xen-hvm.c
> +++ b/xen-hvm.c
> @@ -1226,6 +1226,14 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
>          goto err;
>      }
>
> +    if (xen_domid_restrict) {
> +        rc = xen_restrict(xen_domid);
> +        if (rc < 0) {
> +            error_report("failed to restrict: error %d", errno);
> +            goto err;
> +        }
> +    }
> +
>      xen_create_ioreq_server(xen_domid, &state->ioservid);
>
>      state->exit.notify = xen_exit_notifier;
>
Paul Durrant March 20, 2017, 8:41 a.m. UTC | #2
> -----Original Message-----
> From: Philippe Mathieu-Daudé [mailto:philippe.mathieu.daude@gmail.com]
> On Behalf Of Philippe Mathieu-Daudé
> Sent: 17 March 2017 21:21
> To: Paul Durrant <Paul.Durrant@citrix.com>; qemu-devel@nongnu.org; xen-
> devel@lists.xenproject.org
> Cc: Anthony Perard <anthony.perard@citrix.com>; Paolo Bonzini
> <pbonzini@redhat.com>; Stefano Stabellini <sstabellini@kernel.org>
> Subject: Re: [Qemu-devel] [PATCH] xen: use libxendevice model to restrict
> operations
> 
> Hi Paul,
> 
> On 03/17/2017 10:30 AM, Paul Durrant wrote:
> > This patch adds a command-line option (-xen-domid-restrict) which will
> > use the new libxendevicemodel API to restrict devicemodel operations to
> > the specified domid.
> >
> > This patch also adds a tracepoint to allow successful enabling of the
> > restriction to be monitored.
> >
> > 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>
> >
> > NOTE: This is already re-based on Juergen Gross's patch "xen: use 5 digit
> >       xen versions" and so should not be applied until after that patch
> >       has been applied.
> > ---
> >  hw/xen/trace-events         |  1 +
> >  include/hw/xen/xen.h        |  1 +
> >  include/hw/xen/xen_common.h | 23 +++++++++++++++++++++++
> >  qemu-options.hx             |  6 ++++++
> >  vl.c                        |  8 ++++++++
> >  xen-hvm.c                   |  8 ++++++++
> >  6 files changed, 47 insertions(+)
> >
> > diff --git a/hw/xen/trace-events b/hw/xen/trace-events
> > index c4fb6f1..a5b5e8b 100644
> > --- a/hw/xen/trace-events
> > +++ b/hw/xen/trace-events
> > @@ -11,3 +11,4 @@ xen_map_portio_range(uint32_t id, uint64_t
> start_addr, uint64_t end_addr) "id: %
> >  xen_unmap_portio_range(uint32_t id, uint64_t start_addr, uint64_t
> end_addr) "id: %u start: %#"PRIx64" end: %#"PRIx64
> >  xen_map_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id:
> %u bdf: %02x.%02x.%02x"
> >  xen_unmap_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id:
> %u bdf: %02x.%02x.%02x"
> > +xen_domid_restrict(void) ""
> > diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
> > index 2b1733b..7efcdaa 100644
> > --- a/include/hw/xen/xen.h
> > +++ b/include/hw/xen/xen.h
> > @@ -21,6 +21,7 @@ enum xen_mode {
> >
> >  extern uint32_t xen_domid;
> >  extern enum xen_mode xen_mode;
> > +extern bool xen_domid_restrict;
> >
> >  extern bool xen_allowed;
> >
> > diff --git a/include/hw/xen/xen_common.h
> b/include/hw/xen/xen_common.h
> > index df098c7..5962bc4 100644
> > --- a/include/hw/xen/xen_common.h
> > +++ b/include/hw/xen/xen_common.h
> > @@ -152,6 +152,13 @@ static inline int xendevicemodel_set_mem_type(
> >      return xc_hvm_set_mem_type(dmod, domid, mem_type, first_pfn, nr);
> >  }
> >
> > +static inline int xendevicemodel_restrict(
> > +    xendevicemodel_handle *dmod, domid_t domid)
> > +{
> > +    errno = ENOTTY;
> > +    return -1;
> > +}
> > +
> >  #else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40900 */
> >
> >  #include <xendevicemodel.h>
> > @@ -206,6 +213,22 @@ static inline int xen_modified_memory(domid_t
> domid, uint64_t first_pfn,
> >      return xendevicemodel_modified_memory(xen_dmod, domid,
> first_pfn, nr);
> >  }
> >
> > +static inline int xen_restrict(domid_t domid)
> > +{
> > +    int rc = xendevicemodel_restrict(xen_dmod, domid);
> 
> might it be more useful to log the retcode?
> 
>         trace_xen_domid_restrict(rc);
> 
> > +
> > +    if (rc == 0) {
> > +        trace_xen_domid_restrict();
> 
> and drop the previous line.

Actually the retcode is pretty uninteresting but tracing errno would be a good idea so I think I'll do that.

Cheers,

  Paul

> 
> > +        return 0;
> > +    }
> > +
> > +    if (errno == ENOTTY) {
> > +        return 0;
> > +    }
> > +
> > +    return rc;
> > +}
> > +
> >  /* Xen 4.2 through 4.6 */
> >  #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40701
> >
> > diff --git a/qemu-options.hx b/qemu-options.hx
> > index 99af8ed..4aab077 100644
> > --- a/qemu-options.hx
> > +++ b/qemu-options.hx
> > @@ -3354,6 +3354,10 @@ DEF("xen-attach", 0,
> QEMU_OPTION_xen_attach,
> >      "-xen-attach     attach to existing xen domain\n"
> >      "                xend will use this when starting QEMU\n",
> >      QEMU_ARCH_ALL)
> > +DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
> > +    "-xen-domid-restrict     restrict set of available xen operations\n"
> > +    "                        to specified domain id\n",
> > +    QEMU_ARCH_ALL)
> >  STEXI
> >  @item -xen-domid @var{id}
> >  @findex -xen-domid
> > @@ -3366,6 +3370,8 @@ Warning: should not be used when xend is in use
> (XEN only).
> >  @findex -xen-attach
> >  Attach to existing xen domain.
> >  xend will use this when starting QEMU (XEN only).
> > +@findex -xen-domid-restrict
> > +Restrict set of available xen operations to specified domain id (XEN only).
> >  ETEXI
> >
> >  DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
> > diff --git a/vl.c b/vl.c
> > index 0b4ed52..f46e070 100644
> > --- a/vl.c
> > +++ b/vl.c
> > @@ -205,6 +205,7 @@ static NotifierList machine_init_done_notifiers =
> >  bool xen_allowed;
> >  uint32_t xen_domid;
> >  enum xen_mode xen_mode = XEN_EMULATE;
> > +bool xen_domid_restrict;
> >
> >  static int has_defaults = 1;
> >  static int default_serial = 1;
> > @@ -3933,6 +3934,13 @@ int main(int argc, char **argv, char **envp)
> >                  }
> >                  xen_mode = XEN_ATTACH;
> >                  break;
> > +            case QEMU_OPTION_xen_domid_restrict:
> > +                if (!(xen_available())) {
> > +                    error_report("Option not supported for this target");
> > +                    exit(1);
> > +                }
> > +                xen_domid_restrict = true;
> > +                break;
> >              case QEMU_OPTION_trace:
> >                  g_free(trace_file);
> >                  trace_file = trace_opt_parse(optarg);
> > diff --git a/xen-hvm.c b/xen-hvm.c
> > index 4b928cf..335e263 100644
> > --- a/xen-hvm.c
> > +++ b/xen-hvm.c
> > @@ -1226,6 +1226,14 @@ void xen_hvm_init(PCMachineState *pcms,
> MemoryRegion **ram_memory)
> >          goto err;
> >      }
> >
> > +    if (xen_domid_restrict) {
> > +        rc = xen_restrict(xen_domid);
> > +        if (rc < 0) {
> > +            error_report("failed to restrict: error %d", errno);
> > +            goto err;
> > +        }
> > +    }
> > +
> >      xen_create_ioreq_server(xen_domid, &state->ioservid);
> >
> >      state->exit.notify = xen_exit_notifier;
> >
diff mbox

Patch

diff --git a/hw/xen/trace-events b/hw/xen/trace-events
index c4fb6f1..a5b5e8b 100644
--- a/hw/xen/trace-events
+++ b/hw/xen/trace-events
@@ -11,3 +11,4 @@  xen_map_portio_range(uint32_t id, uint64_t start_addr, uint64_t end_addr) "id: %
 xen_unmap_portio_range(uint32_t id, uint64_t start_addr, uint64_t end_addr) "id: %u start: %#"PRIx64" end: %#"PRIx64
 xen_map_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id: %u bdf: %02x.%02x.%02x"
 xen_unmap_pcidev(uint32_t id, uint8_t bus, uint8_t dev, uint8_t func) "id: %u bdf: %02x.%02x.%02x"
+xen_domid_restrict(void) ""
diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
index 2b1733b..7efcdaa 100644
--- a/include/hw/xen/xen.h
+++ b/include/hw/xen/xen.h
@@ -21,6 +21,7 @@  enum xen_mode {
 
 extern uint32_t xen_domid;
 extern enum xen_mode xen_mode;
+extern bool xen_domid_restrict;
 
 extern bool xen_allowed;
 
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index df098c7..5962bc4 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -152,6 +152,13 @@  static inline int xendevicemodel_set_mem_type(
     return xc_hvm_set_mem_type(dmod, domid, mem_type, first_pfn, nr);
 }
 
+static inline int xendevicemodel_restrict(
+    xendevicemodel_handle *dmod, domid_t domid)
+{
+    errno = ENOTTY;
+    return -1;
+}
+
 #else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40900 */
 
 #include <xendevicemodel.h>
@@ -206,6 +213,22 @@  static inline int xen_modified_memory(domid_t domid, uint64_t first_pfn,
     return xendevicemodel_modified_memory(xen_dmod, domid, first_pfn, nr);
 }
 
+static inline int xen_restrict(domid_t domid)
+{
+    int rc = xendevicemodel_restrict(xen_dmod, domid);
+
+    if (rc == 0) {
+        trace_xen_domid_restrict();
+        return 0;
+    }
+
+    if (errno == ENOTTY) {
+        return 0;
+    }
+
+    return rc;
+}
+
 /* Xen 4.2 through 4.6 */
 #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40701
 
diff --git a/qemu-options.hx b/qemu-options.hx
index 99af8ed..4aab077 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -3354,6 +3354,10 @@  DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
     "-xen-attach     attach to existing xen domain\n"
     "                xend will use this when starting QEMU\n",
     QEMU_ARCH_ALL)
+DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
+    "-xen-domid-restrict     restrict set of available xen operations\n"
+    "                        to specified domain id\n",
+    QEMU_ARCH_ALL)
 STEXI
 @item -xen-domid @var{id}
 @findex -xen-domid
@@ -3366,6 +3370,8 @@  Warning: should not be used when xend is in use (XEN only).
 @findex -xen-attach
 Attach to existing xen domain.
 xend will use this when starting QEMU (XEN only).
+@findex -xen-domid-restrict
+Restrict set of available xen operations to specified domain id (XEN only).
 ETEXI
 
 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
diff --git a/vl.c b/vl.c
index 0b4ed52..f46e070 100644
--- a/vl.c
+++ b/vl.c
@@ -205,6 +205,7 @@  static NotifierList machine_init_done_notifiers =
 bool xen_allowed;
 uint32_t xen_domid;
 enum xen_mode xen_mode = XEN_EMULATE;
+bool xen_domid_restrict;
 
 static int has_defaults = 1;
 static int default_serial = 1;
@@ -3933,6 +3934,13 @@  int main(int argc, char **argv, char **envp)
                 }
                 xen_mode = XEN_ATTACH;
                 break;
+            case QEMU_OPTION_xen_domid_restrict:
+                if (!(xen_available())) {
+                    error_report("Option not supported for this target");
+                    exit(1);
+                }
+                xen_domid_restrict = true;
+                break;
             case QEMU_OPTION_trace:
                 g_free(trace_file);
                 trace_file = trace_opt_parse(optarg);
diff --git a/xen-hvm.c b/xen-hvm.c
index 4b928cf..335e263 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -1226,6 +1226,14 @@  void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
         goto err;
     }
 
+    if (xen_domid_restrict) {
+        rc = xen_restrict(xen_domid);
+        if (rc < 0) {
+            error_report("failed to restrict: error %d", errno);
+            goto err;
+        }
+    }
+
     xen_create_ioreq_server(xen_domid, &state->ioservid);
 
     state->exit.notify = xen_exit_notifier;