[PATCH 5/7] virtio-iommu : Retrieve page size mask on virtio_iommu_set_iommu_device()

Eric Auger posted 7 patches 5 months ago
Maintainers: Alex Williamson <alex.williamson@redhat.com>, "Cédric Le Goater" <clg@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>, Eric Auger <eric.auger@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>, David Hildenbrand <david@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Yi Liu <yi.l.liu@intel.com>, Zhenzhong Duan <zhenzhong.duan@intel.com>
There is a newer version of this series
[PATCH 5/7] virtio-iommu : Retrieve page size mask on virtio_iommu_set_iommu_device()
Posted by Eric Auger 5 months ago
Retrieve the Host IOMMU Device page size mask when this latter is set.
This allows to get the information much sooner than when relying on
IOMMU MR set_page_size_mask() call, whcih happens when the IOMMU MR
gets enabled. We introduce check_page_size_mask() helper whose code
is inherited from current virtio_iommu_set_page_size_mask()
implementation. This callback will be removed in a subsequent patch.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 hw/virtio/virtio-iommu.c | 55 ++++++++++++++++++++++++++++++++++++++--
 hw/virtio/trace-events   |  1 +
 2 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index b8f75d2b1a..631589735a 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -598,9 +598,39 @@ out:
     return ret;
 }
 
+static bool check_page_size_mask(VirtIOIOMMU *viommu, uint64_t new_mask,
+                                 Error **errp)
+{
+    uint64_t cur_mask = viommu->config.page_size_mask;
+
+    if ((cur_mask & new_mask) == 0) {
+        error_setg(errp, "virtio-iommu reports a page size mask 0x%"PRIx64
+                   " incompatible with currently supported mask 0x%"PRIx64,
+                   new_mask, cur_mask);
+        return false;
+    }
+    /*
+     * Once the granule is frozen we can't change the mask anymore. If by
+     * chance the hotplugged device supports the same granule, we can still
+     * accept it.
+     */
+    if (viommu->granule_frozen) {
+        int cur_granule = ctz64(cur_mask);
+
+        if (!(BIT_ULL(cur_granule) & new_mask)) {
+            error_setg(errp,
+                       "virtio-iommu does not support frozen granule 0x%llx",
+                       BIT_ULL(cur_granule));
+            return false;
+        }
+    }
+    return true;
+}
+
 static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
                                           HostIOMMUDevice *hiod, Error **errp)
 {
+    ERRP_GUARD();
     VirtIOIOMMU *viommu = opaque;
     HostIOMMUDeviceClass *hiodc = HOST_IOMMU_DEVICE_GET_CLASS(hiod);
     struct hiod_key *new_key;
@@ -623,8 +653,26 @@ static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
                                                 hiod->aliased_devfn,
                                                 host_iova_ranges, errp);
         if (ret) {
-            g_list_free_full(host_iova_ranges, g_free);
-            return false;
+            goto error;
+        }
+    }
+    if (hiodc->get_page_size_mask) {
+        uint64_t new_mask = hiodc->get_page_size_mask(hiod);
+
+        if (check_page_size_mask(viommu, new_mask, errp)) {
+            /*
+             * The default mask depends on the "granule" property. For example,
+             * with 4k granule, it is -(4 * KiB). When an assigned device has
+             * page size restrictions due to the hardware IOMMU configuration,
+             * apply this restriction to the mask.
+             */
+            trace_virtio_iommu_update_page_size_mask(hiod->name,
+                                                     viommu->config.page_size_mask,
+                                                     new_mask);
+            viommu->config.page_size_mask &= new_mask;
+        } else {
+            error_prepend(errp, "%s: ", hiod->name);
+            goto error;
         }
     }
 
@@ -637,6 +685,9 @@ static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
     g_list_free_full(host_iova_ranges, g_free);
 
     return true;
+error:
+    g_list_free_full(host_iova_ranges, g_free);
+    return false;
 }
 
 static void
diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 3cf84e04a7..599d855ff6 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -132,6 +132,7 @@ virtio_iommu_notify_map(const char *name, uint64_t virt_start, uint64_t virt_end
 virtio_iommu_notify_unmap(const char *name, uint64_t virt_start, uint64_t virt_end) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
 virtio_iommu_remap(const char *name, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64" phys_start=0x%"PRIx64
 virtio_iommu_set_page_size_mask(const char *name, uint64_t old, uint64_t new) "mr=%s old_mask=0x%"PRIx64" new_mask=0x%"PRIx64
+virtio_iommu_update_page_size_mask(const char *name, uint64_t old, uint64_t new) "host iommu device=%s old_mask=0x%"PRIx64" new_mask=0x%"PRIx64
 virtio_iommu_notify_flag_add(const char *name) "add notifier to mr %s"
 virtio_iommu_notify_flag_del(const char *name) "del notifier from mr %s"
 virtio_iommu_switch_address_space(uint8_t bus, uint8_t slot, uint8_t fn, bool on) "Device %02x:%02x.%x switching address space (iommu enabled=%d)"
-- 
2.41.0
RE: [PATCH 5/7] virtio-iommu : Retrieve page size mask on virtio_iommu_set_iommu_device()
Posted by Duan, Zhenzhong 5 months ago
Hi Eric,

>-----Original Message-----
>From: Eric Auger <eric.auger@redhat.com>
>Subject: [PATCH 5/7] virtio-iommu : Retrieve page size mask on
>virtio_iommu_set_iommu_device()
>
>Retrieve the Host IOMMU Device page size mask when this latter is set.
>This allows to get the information much sooner than when relying on
>IOMMU MR set_page_size_mask() call, whcih happens when the IOMMU
>MR
>gets enabled. We introduce check_page_size_mask() helper whose code
>is inherited from current virtio_iommu_set_page_size_mask()
>implementation. This callback will be removed in a subsequent patch.
>
>Signed-off-by: Eric Auger <eric.auger@redhat.com>
>---
> hw/virtio/virtio-iommu.c | 55
>++++++++++++++++++++++++++++++++++++++--
> hw/virtio/trace-events   |  1 +
> 2 files changed, 54 insertions(+), 2 deletions(-)
>
>diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
>index b8f75d2b1a..631589735a 100644
>--- a/hw/virtio/virtio-iommu.c
>+++ b/hw/virtio/virtio-iommu.c
>@@ -598,9 +598,39 @@ out:
>     return ret;
> }
>
>+static bool check_page_size_mask(VirtIOIOMMU *viommu, uint64_t
>new_mask,
>+                                 Error **errp)
>+{
>+    uint64_t cur_mask = viommu->config.page_size_mask;
>+
>+    if ((cur_mask & new_mask) == 0) {
>+        error_setg(errp, "virtio-iommu reports a page size mask 0x%"PRIx64
>+                   " incompatible with currently supported mask 0x%"PRIx64,
>+                   new_mask, cur_mask);
>+        return false;
>+    }
>+    /*
>+     * Once the granule is frozen we can't change the mask anymore. If by
>+     * chance the hotplugged device supports the same granule, we can still
>+     * accept it.
>+     */
>+    if (viommu->granule_frozen) {
>+        int cur_granule = ctz64(cur_mask);
>+
>+        if (!(BIT_ULL(cur_granule) & new_mask)) {
>+            error_setg(errp,
>+                       "virtio-iommu does not support frozen granule 0x%llx",
>+                       BIT_ULL(cur_granule));
>+            return false;
>+        }
>+    }
>+    return true;
>+}
>+
> static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque,
>int devfn,
>                                           HostIOMMUDevice *hiod, Error **errp)
> {
>+    ERRP_GUARD();
>     VirtIOIOMMU *viommu = opaque;
>     HostIOMMUDeviceClass *hiodc =
>HOST_IOMMU_DEVICE_GET_CLASS(hiod);
>     struct hiod_key *new_key;
>@@ -623,8 +653,26 @@ static bool
>virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
>                                                 hiod->aliased_devfn,
>                                                 host_iova_ranges, errp);
>         if (ret) {
>-            g_list_free_full(host_iova_ranges, g_free);
>-            return false;
>+            goto error;
>+        }
>+    }
>+    if (hiodc->get_page_size_mask) {
>+        uint64_t new_mask = hiodc->get_page_size_mask(hiod);
>+
>+        if (check_page_size_mask(viommu, new_mask, errp)) {
>+            /*
>+             * The default mask depends on the "granule" property. For example,
>+             * with 4k granule, it is -(4 * KiB). When an assigned device has
>+             * page size restrictions due to the hardware IOMMU configuration,
>+             * apply this restriction to the mask.
>+             */
>+            trace_virtio_iommu_update_page_size_mask(hiod->name,
>+                                                     viommu->config.page_size_mask,
>+                                                     new_mask);
>+            viommu->config.page_size_mask &= new_mask;

This is a bit different from original logic, it may update page_size_mask after frozen.
Will that make issue?

Except this question, for all other patches,

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>

Thanks
Zhenzhong

>+        } else {
>+            error_prepend(errp, "%s: ", hiod->name);
>+            goto error;
>         }
>     }
>
>@@ -637,6 +685,9 @@ static bool
>virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
>     g_list_free_full(host_iova_ranges, g_free);
>
>     return true;
>+error:
>+    g_list_free_full(host_iova_ranges, g_free);
>+    return false;
> }
>
> static void
>diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
>index 3cf84e04a7..599d855ff6 100644
>--- a/hw/virtio/trace-events
>+++ b/hw/virtio/trace-events
>@@ -132,6 +132,7 @@ virtio_iommu_notify_map(const char *name,
>uint64_t virt_start, uint64_t virt_end
> virtio_iommu_notify_unmap(const char *name, uint64_t virt_start,
>uint64_t virt_end) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
> virtio_iommu_remap(const char *name, uint64_t virt_start, uint64_t
>virt_end, uint64_t phys_start) "mr=%s virt_start=0x%"PRIx64"
>virt_end=0x%"PRIx64" phys_start=0x%"PRIx64
> virtio_iommu_set_page_size_mask(const char *name, uint64_t old,
>uint64_t new) "mr=%s old_mask=0x%"PRIx64" new_mask=0x%"PRIx64
>+virtio_iommu_update_page_size_mask(const char *name, uint64_t old,
>uint64_t new) "host iommu device=%s old_mask=0x%"PRIx64"
>new_mask=0x%"PRIx64
> virtio_iommu_notify_flag_add(const char *name) "add notifier to mr %s"
> virtio_iommu_notify_flag_del(const char *name) "del notifier from mr %s"
> virtio_iommu_switch_address_space(uint8_t bus, uint8_t slot, uint8_t fn,
>bool on) "Device %02x:%02x.%x switching address space (iommu
>enabled=%d)"
>--
>2.41.0
Re: [PATCH 5/7] virtio-iommu : Retrieve page size mask on virtio_iommu_set_iommu_device()
Posted by Eric Auger 5 months ago
Hi Zhenhong,

On 6/27/24 13:32, Duan, Zhenzhong wrote:
> Hi Eric,
>
>> -----Original Message-----
>> From: Eric Auger <eric.auger@redhat.com>
>> Subject: [PATCH 5/7] virtio-iommu : Retrieve page size mask on
>> virtio_iommu_set_iommu_device()
>>
>> Retrieve the Host IOMMU Device page size mask when this latter is set.
>> This allows to get the information much sooner than when relying on
>> IOMMU MR set_page_size_mask() call, whcih happens when the IOMMU
>> MR
>> gets enabled. We introduce check_page_size_mask() helper whose code
>> is inherited from current virtio_iommu_set_page_size_mask()
>> implementation. This callback will be removed in a subsequent patch.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>> hw/virtio/virtio-iommu.c | 55
>> ++++++++++++++++++++++++++++++++++++++--
>> hw/virtio/trace-events   |  1 +
>> 2 files changed, 54 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
>> index b8f75d2b1a..631589735a 100644
>> --- a/hw/virtio/virtio-iommu.c
>> +++ b/hw/virtio/virtio-iommu.c
>> @@ -598,9 +598,39 @@ out:
>>     return ret;
>> }
>>
>> +static bool check_page_size_mask(VirtIOIOMMU *viommu, uint64_t
>> new_mask,
>> +                                 Error **errp)
>> +{
>> +    uint64_t cur_mask = viommu->config.page_size_mask;
>> +
>> +    if ((cur_mask & new_mask) == 0) {
>> +        error_setg(errp, "virtio-iommu reports a page size mask 0x%"PRIx64
>> +                   " incompatible with currently supported mask 0x%"PRIx64,
>> +                   new_mask, cur_mask);
>> +        return false;
>> +    }
>> +    /*
>> +     * Once the granule is frozen we can't change the mask anymore. If by
>> +     * chance the hotplugged device supports the same granule, we can still
>> +     * accept it.
>> +     */
>> +    if (viommu->granule_frozen) {
>> +        int cur_granule = ctz64(cur_mask);
>> +
>> +        if (!(BIT_ULL(cur_granule) & new_mask)) {
>> +            error_setg(errp,
>> +                       "virtio-iommu does not support frozen granule 0x%llx",
>> +                       BIT_ULL(cur_granule));
>> +            return false;
>> +        }
>> +    }
>> +    return true;
>> +}
>> +
>> static bool virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque,
>> int devfn,
>>                                           HostIOMMUDevice *hiod, Error **errp)
>> {
>> +    ERRP_GUARD();
>>     VirtIOIOMMU *viommu = opaque;
>>     HostIOMMUDeviceClass *hiodc =
>> HOST_IOMMU_DEVICE_GET_CLASS(hiod);
>>     struct hiod_key *new_key;
>> @@ -623,8 +653,26 @@ static bool
>> virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
>>                                                 hiod->aliased_devfn,
>>                                                 host_iova_ranges, errp);
>>         if (ret) {
>> -            g_list_free_full(host_iova_ranges, g_free);
>> -            return false;
>> +            goto error;
>> +        }
>> +    }
>> +    if (hiodc->get_page_size_mask) {
>> +        uint64_t new_mask = hiodc->get_page_size_mask(hiod);
>> +
>> +        if (check_page_size_mask(viommu, new_mask, errp)) {
>> +            /*
>> +             * The default mask depends on the "granule" property. For example,
>> +             * with 4k granule, it is -(4 * KiB). When an assigned device has
>> +             * page size restrictions due to the hardware IOMMU configuration,
>> +             * apply this restriction to the mask.
>> +             */
>> +            trace_virtio_iommu_update_page_size_mask(hiod->name,
>> +                                                     viommu->config.page_size_mask,
>> +                                                     new_mask);
>> +            viommu->config.page_size_mask &= new_mask;
> This is a bit different from original logic, it may update page_size_mask after frozen.
> Will that make issue?
You're fully right. I need to replace

viommu->config.page_size_mask &= new_mask;
by
if (s->granule_frozen) {
    viommu->config.page_size_mask &= new_mask;
}    

> Except this question, for all other patches,
>
> Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Thanks!

Eric
>
> Thanks
> Zhenzhong
>
>> +        } else {
>> +            error_prepend(errp, "%s: ", hiod->name);
>> +            goto error;
>>         }
>>     }
>>
>> @@ -637,6 +685,9 @@ static bool
>> virtio_iommu_set_iommu_device(PCIBus *bus, void *opaque, int devfn,
>>     g_list_free_full(host_iova_ranges, g_free);
>>
>>     return true;
>> +error:
>> +    g_list_free_full(host_iova_ranges, g_free);
>> +    return false;
>> }
>>
>> static void
>> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
>> index 3cf84e04a7..599d855ff6 100644
>> --- a/hw/virtio/trace-events
>> +++ b/hw/virtio/trace-events
>> @@ -132,6 +132,7 @@ virtio_iommu_notify_map(const char *name,
>> uint64_t virt_start, uint64_t virt_end
>> virtio_iommu_notify_unmap(const char *name, uint64_t virt_start,
>> uint64_t virt_end) "mr=%s virt_start=0x%"PRIx64" virt_end=0x%"PRIx64
>> virtio_iommu_remap(const char *name, uint64_t virt_start, uint64_t
>> virt_end, uint64_t phys_start) "mr=%s virt_start=0x%"PRIx64"
>> virt_end=0x%"PRIx64" phys_start=0x%"PRIx64
>> virtio_iommu_set_page_size_mask(const char *name, uint64_t old,
>> uint64_t new) "mr=%s old_mask=0x%"PRIx64" new_mask=0x%"PRIx64
>> +virtio_iommu_update_page_size_mask(const char *name, uint64_t old,
>> uint64_t new) "host iommu device=%s old_mask=0x%"PRIx64"
>> new_mask=0x%"PRIx64
>> virtio_iommu_notify_flag_add(const char *name) "add notifier to mr %s"
>> virtio_iommu_notify_flag_del(const char *name) "del notifier from mr %s"
>> virtio_iommu_switch_address_space(uint8_t bus, uint8_t slot, uint8_t fn,
>> bool on) "Device %02x:%02x.%x switching address space (iommu
>> enabled=%d)"
>> --
>> 2.41.0