|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [v4][PATCH 11/19] tools: introduce some new parameters to set rdm policy
This patch introduces user configurable parameters to specify RDM
resource and according policies,
Global RDM parameter:
rdm = "type=none/host,reserve=strict/relaxed"
Per-device RDM parameter:
pci = [ 'sbdf, rdm_reserve=strict/relaxed' ]
Global RDM parameter, "type", allows user to specify reserved regions
explicitly, e.g. using 'host' to include all reserved regions reported
on this platform which is good to handle hotplug scenario. In the future
this parameter may be further extended to allow specifying random regions,
e.g. even those belonging to another platform as a preparation for live
migration with passthrough devices. Instead, 'none' means we have nothing
to do all reserved regions and ignore all policies, so guest work as before.
'strict/relaxed' policy decides how to handle conflict when reserving RDM
regions in pfn space. If conflict exists, 'strict' means an immediate error
so VM will be killed, while 'relaxed' allows moving forward with a warning
message thrown out.
Default per-device RDM policy is 'strict', while default global RDM policy
is 'relaxed'. When both policies are specified on a given region, 'strict' is
always preferred.
CC: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
CC: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
CC: Ian Campbell <ian.campbell@xxxxxxxxxx>
CC: Wei Liu <wei.liu2@xxxxxxxxxx>
Signed-off-by: Tiejun Chen <tiejun.chen@xxxxxxxxx>
---
v4:
* No need to define init_val for libxl_rdm_reserve_type since its just zero
* Grab those changes to xl/libxlu to as a final patch
docs/man/xl.cfg.pod.5 | 50 ++++++++++++++++++++++++++++++++++++++++++++
docs/misc/vtd.txt | 24 +++++++++++++++++++++
tools/libxl/libxl_create.c | 13 ++++++++++++
tools/libxl/libxl_internal.h | 2 ++
tools/libxl/libxl_pci.c | 3 +++
tools/libxl/libxl_types.idl | 18 ++++++++++++++++
6 files changed, 110 insertions(+)
diff --git a/docs/man/xl.cfg.pod.5 b/docs/man/xl.cfg.pod.5
index a3e0e2e..638b350 100644
--- a/docs/man/xl.cfg.pod.5
+++ b/docs/man/xl.cfg.pod.5
@@ -655,6 +655,49 @@ assigned slave device.
=back
+=item B<rdm="RDM_RESERVE_STRING">
+
+(HVM/x86 only) Specifies the information about Reserved Device Memory (RDM),
+which is necessary to enable robust device passthrough. One example of RDM
+is reported through ACPI Reserved Memory Region Reporting (RMRR) structure
+on x86 platform.
+
+B<RDM_RESERVE_STRING> has the form C<[KEY=VALUE,KEY=VALUE,...> where:
+
+=over 4
+
+=item B<KEY=VALUE>
+
+Possible B<KEY>s are:
+
+=over 4
+
+=item B<type="STRING">
+
+Currently we just have two types:
+
+"host" means all reserved device memory on this platform should be reserved
+in this VM's guest address space space. This global RDM parameter allows
+user to specify reserved regions explicitly. And using "host" to include all
+reserved regions reported on this platform which is good to handle hotplug
+scenario. In the future this parameter may be further extended to allow
+specifying random regions, e.g. even those belonging to another platform as
+a preparation for live migration with passthrough devices.
+
+"none" means we have nothing to do all reserved regions and ignore all
policies,
+so guest work as before.
+
+=over 4
+
+=item B<reserve="STRING">
+
+Conflict may be detected when reserving reserved device memory in guest address
+space. "strict" means an unsolved conflict leads to immediate VM crash, while
+"relaxed" allows VM moving forward with a warning message thrown out. "relaxed"
+is default.
+
+Note this may be overridden by rdm_reserve option in PCI device configuration.
+
=item B<pci=[ "PCI_SPEC_STRING", "PCI_SPEC_STRING", ... ]>
Specifies the host PCI devices to passthrough to this guest. Each
B<PCI_SPEC_STRING>
@@ -717,6 +760,13 @@ dom0 without confirmation. Please use with care.
D0-D3hot power management states for the PCI device. False (0) by
default.
+=item B<rdm_reserv="STRING">
+
+(HVM/x86 only) This is same as reserve option above but just specific
+to a given device, and "strict" is default here.
+
+Note this would override global B<rdm> option.
+
=back
=back
diff --git a/docs/misc/vtd.txt b/docs/misc/vtd.txt
index 9af0e99..7d63c47 100644
--- a/docs/misc/vtd.txt
+++ b/docs/misc/vtd.txt
@@ -111,6 +111,30 @@ in the config file:
To override for a specific device:
pci = [ '01:00.0,msitranslate=0', '03:00.0' ]
+RDM, 'reserved device memory', for PCI Device Passthrough
+---------------------------------------------------------
+
+There are some devices the BIOS controls, for e.g. USB devices to perform
+PS2 emulation. The regions of memory used for these devices are marked
+reserved in the e820 map. When we turn on DMA translation, DMA to those
+regions will fail. Hence BIOS uses RMRR to specify these regions along with
+devices that need to access these regions. OS is expected to setup
+identity mappings for these regions for these devices to access these regions.
+
+While creating a VM we should reserve them in advance, and avoid any conflicts.
+So we introduce user configurable parameters to specify RDM resource and
+according policies,
+
+To enable this globally, add "rdm" in the config file:
+
+ rdm = "type=host, reserve=relaxed" (default policy is "relaxed")
+
+Or just for a specific device:
+
+ pci = [ '01:00.0,rdm_reserve=relaxed', '03:00.0,rdm_reserve=strict' ]
+
+For all the options available to RDM, see xl.cfg(5).
+
Caveat on Conventional PCI Device Passthrough
---------------------------------------------
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index 86384d2..6c8ec63 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -105,6 +105,12 @@ static int sched_params_valid(libxl__gc *gc,
return 1;
}
+void libxl__rdm_setdefault(libxl__gc *gc, libxl_domain_build_info *b_info)
+{
+ if (b_info->rdm.reserve == LIBXL_RDM_RESERVE_FLAG_INVALID)
+ b_info->rdm.reserve = LIBXL_RDM_RESERVE_FLAG_RELAXED;
+}
+
int libxl__domain_build_info_setdefault(libxl__gc *gc,
libxl_domain_build_info *b_info)
{
@@ -419,6 +425,8 @@ int libxl__domain_build_info_setdefault(libxl__gc *gc,
libxl_domain_type_to_string(b_info->type));
return ERROR_INVAL;
}
+
+ libxl__rdm_setdefault(gc, b_info);
return 0;
}
@@ -1450,6 +1458,11 @@ static void domcreate_attach_pci(libxl__egc *egc,
libxl__multidev *multidev,
}
for (i = 0; i < d_config->num_pcidevs; i++) {
+ /*
+ * If the rdm global policy is 'strict' we should override each device.
+ */
+ if (d_config->b_info.rdm.reserve == LIBXL_RDM_RESERVE_FLAG_STRICT)
+ d_config->pcidevs[i].rdm_reserve = LIBXL_RDM_RESERVE_FLAG_STRICT;
ret = libxl__device_pci_add(gc, domid, &d_config->pcidevs[i], 1);
if (ret < 0) {
LIBXL__LOG(ctx, LIBXL__LOG_ERROR,
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index e96d6b5..eae1dc6 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -1108,6 +1108,8 @@ _hidden int libxl__device_vtpm_setdefault(libxl__gc *gc,
libxl_device_vtpm *vtpm
_hidden int libxl__device_vfb_setdefault(libxl__gc *gc, libxl_device_vfb *vfb);
_hidden int libxl__device_vkb_setdefault(libxl__gc *gc, libxl_device_vkb *vkb);
_hidden int libxl__device_pci_setdefault(libxl__gc *gc, libxl_device_pci *pci);
+_hidden void libxl__rdm_setdefault(libxl__gc *gc,
+ libxl_domain_build_info *b_info);
_hidden const char *libxl__device_nic_devname(libxl__gc *gc,
uint32_t domid,
diff --git a/tools/libxl/libxl_pci.c b/tools/libxl/libxl_pci.c
index 632c15e..a00d799 100644
--- a/tools/libxl/libxl_pci.c
+++ b/tools/libxl/libxl_pci.c
@@ -1040,6 +1040,9 @@ static int libxl__device_pci_reset(libxl__gc *gc,
unsigned int domain, unsigned
int libxl__device_pci_setdefault(libxl__gc *gc, libxl_device_pci *pci)
{
+ /* We'd like to force reserve rdm specific to a device by default.*/
+ if ( pci->rdm_reserve == LIBXL_RDM_RESERVE_FLAG_INVALID)
+ pci->rdm_reserve = LIBXL_RDM_RESERVE_FLAG_STRICT;
return 0;
}
diff --git a/tools/libxl/libxl_types.idl b/tools/libxl/libxl_types.idl
index 23f27d4..dd91b38 100644
--- a/tools/libxl/libxl_types.idl
+++ b/tools/libxl/libxl_types.idl
@@ -73,6 +73,17 @@ libxl_domain_type = Enumeration("domain_type", [
(2, "PV"),
], init_val = "LIBXL_DOMAIN_TYPE_INVALID")
+libxl_rdm_reserve_type = Enumeration("rdm_reserve_type", [
+ (0, "none"),
+ (1, "host"),
+ ])
+
+libxl_rdm_reserve_flag = Enumeration("rdm_reserve_flag", [
+ (-1, "invalid"),
+ (0, "strict"),
+ (1, "relaxed"),
+ ], init_val = "LIBXL_RDM_RESERVE_FLAG_INVALID")
+
libxl_channel_connection = Enumeration("channel_connection", [
(0, "UNKNOWN"),
(1, "PTY"),
@@ -366,6 +377,11 @@ libxl_vnode_info = Struct("vnode_info", [
("vcpus", libxl_bitmap), # vcpus in this node
])
+libxl_rdm_reserve = Struct("rdm_reserve", [
+ ("type", libxl_rdm_reserve_type),
+ ("reserve", libxl_rdm_reserve_flag),
+ ])
+
libxl_domain_build_info = Struct("domain_build_info",[
("max_vcpus", integer),
("avail_vcpus", libxl_bitmap),
@@ -413,6 +429,7 @@ libxl_domain_build_info = Struct("domain_build_info",[
("kernel", string),
("cmdline", string),
("ramdisk", string),
+ ("rdm", libxl_rdm_reserve),
# Given the complexity of verifying the validity of a device tree,
# libxl doesn't do any security check on it. It's the responsibility
# of the caller to provide only trusted device tree.
@@ -539,6 +556,7 @@ libxl_device_pci = Struct("device_pci", [
("power_mgmt", bool),
("permissive", bool),
("seize", bool),
+ ("rdm_reserve", libxl_rdm_reserve_flag),
])
libxl_device_dtdev = Struct("device_dtdev", [
--
1.9.1
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |