* [PATCH v2 1/3] xen/virtio: restructure xen grant dma setup
2022-10-07 6:41 [PATCH v2 0/3] xen/virtio: support grant based virtio on x86 Juergen Gross
@ 2022-10-07 6:41 ` Juergen Gross
2022-10-07 6:41 ` [PATCH v2 2/3] xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT Juergen Gross
2022-10-07 6:41 ` [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86 Juergen Gross
2 siblings, 0 replies; 6+ messages in thread
From: Juergen Gross @ 2022-10-07 6:41 UTC (permalink / raw)
To: linux-kernel
Cc: Juergen Gross, Stefano Stabellini, Oleksandr Tyshchenko, xen-devel
In order to prepare supporting other means than device tree for
setting up virtio devices under Xen, restructure the functions
xen_is_grant_dma_device() and xen_grant_setup_dma_ops() a little bit.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Tested-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Arm64 only
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
V2:
- rename xen_dt_grant_setup_dma_ops() (Oleksandr Tyshchenko)
---
drivers/xen/grant-dma-ops.c | 68 +++++++++++++++++++++++--------------
1 file changed, 43 insertions(+), 25 deletions(-)
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index 8973fc1e9ccc..646ca913c05c 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -273,22 +273,28 @@ static const struct dma_map_ops xen_grant_dma_ops = {
.dma_supported = xen_grant_dma_supported,
};
-bool xen_is_grant_dma_device(struct device *dev)
+static bool xen_is_dt_grant_dma_device(struct device *dev)
{
struct device_node *iommu_np;
bool has_iommu;
- /* XXX Handle only DT devices for now */
- if (!dev->of_node)
- return false;
-
iommu_np = of_parse_phandle(dev->of_node, "iommus", 0);
- has_iommu = iommu_np && of_device_is_compatible(iommu_np, "xen,grant-dma");
+ has_iommu = iommu_np &&
+ of_device_is_compatible(iommu_np, "xen,grant-dma");
of_node_put(iommu_np);
return has_iommu;
}
+bool xen_is_grant_dma_device(struct device *dev)
+{
+ /* XXX Handle only DT devices for now */
+ if (dev->of_node)
+ return xen_is_dt_grant_dma_device(dev);
+
+ return false;
+}
+
bool xen_virtio_mem_acc(struct virtio_device *dev)
{
if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
@@ -297,45 +303,56 @@ bool xen_virtio_mem_acc(struct virtio_device *dev)
return xen_is_grant_dma_device(dev->dev.parent);
}
-void xen_grant_setup_dma_ops(struct device *dev)
+static int xen_dt_grant_init_backend_domid(struct device *dev,
+ struct xen_grant_dma_data *data)
{
- struct xen_grant_dma_data *data;
struct of_phandle_args iommu_spec;
- data = find_xen_grant_dma_data(dev);
- if (data) {
- dev_err(dev, "Xen grant DMA data is already created\n");
- return;
- }
-
- /* XXX ACPI device unsupported for now */
- if (!dev->of_node)
- goto err;
-
if (of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells",
0, &iommu_spec)) {
dev_err(dev, "Cannot parse iommus property\n");
- goto err;
+ return -ESRCH;
}
if (!of_device_is_compatible(iommu_spec.np, "xen,grant-dma") ||
iommu_spec.args_count != 1) {
dev_err(dev, "Incompatible IOMMU node\n");
of_node_put(iommu_spec.np);
- goto err;
+ return -ESRCH;
}
of_node_put(iommu_spec.np);
+ /*
+ * The endpoint ID here means the ID of the domain where the
+ * corresponding backend is running
+ */
+ data->backend_domid = iommu_spec.args[0];
+
+ return 0;
+}
+
+void xen_grant_setup_dma_ops(struct device *dev)
+{
+ struct xen_grant_dma_data *data;
+
+ data = find_xen_grant_dma_data(dev);
+ if (data) {
+ dev_err(dev, "Xen grant DMA data is already created\n");
+ return;
+ }
+
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
goto err;
- /*
- * The endpoint ID here means the ID of the domain where the corresponding
- * backend is running
- */
- data->backend_domid = iommu_spec.args[0];
+ if (dev->of_node) {
+ if (xen_dt_grant_init_backend_domid(dev, data))
+ goto err;
+ } else {
+ /* XXX ACPI device unsupported for now */
+ goto err;
+ }
if (xa_err(xa_store(&xen_grant_dma_devices, (unsigned long)dev, data,
GFP_KERNEL))) {
@@ -348,6 +365,7 @@ void xen_grant_setup_dma_ops(struct device *dev)
return;
err:
+ devm_kfree(dev, data);
dev_err(dev, "Cannot set up Xen grant DMA ops, retain platform DMA ops\n");
}
--
2.35.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 2/3] xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT
2022-10-07 6:41 [PATCH v2 0/3] xen/virtio: support grant based virtio on x86 Juergen Gross
2022-10-07 6:41 ` [PATCH v2 1/3] xen/virtio: restructure xen grant dma setup Juergen Gross
@ 2022-10-07 6:41 ` Juergen Gross
2022-10-07 6:41 ` [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86 Juergen Gross
2 siblings, 0 replies; 6+ messages in thread
From: Juergen Gross @ 2022-10-07 6:41 UTC (permalink / raw)
To: linux-kernel
Cc: Juergen Gross, Stefano Stabellini, Oleksandr Tyshchenko, xen-devel
With CONFIG_XEN_VIRTIO_FORCE_GRANT set the default backend domid to 0,
enabling to use xen_grant_dma_ops for those devices.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
drivers/xen/grant-dma-ops.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index 646ca913c05c..c703b77b33c9 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -349,6 +349,9 @@ void xen_grant_setup_dma_ops(struct device *dev)
if (dev->of_node) {
if (xen_dt_grant_init_backend_domid(dev, data))
goto err;
+ } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT)) {
+ dev_info(dev, "Using dom0 as backend\n");
+ data->backend_domid = 0;
} else {
/* XXX ACPI device unsupported for now */
goto err;
--
2.35.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86
2022-10-07 6:41 [PATCH v2 0/3] xen/virtio: support grant based virtio on x86 Juergen Gross
2022-10-07 6:41 ` [PATCH v2 1/3] xen/virtio: restructure xen grant dma setup Juergen Gross
2022-10-07 6:41 ` [PATCH v2 2/3] xen/virtio: use dom0 as default backend for CONFIG_XEN_VIRTIO_FORCE_GRANT Juergen Gross
@ 2022-10-07 6:41 ` Juergen Gross
2022-10-07 14:00 ` Oleksandr Tyshchenko
2 siblings, 1 reply; 6+ messages in thread
From: Juergen Gross @ 2022-10-07 6:41 UTC (permalink / raw)
To: linux-kernel, x86
Cc: Juergen Gross, Boris Ostrovsky, Thomas Gleixner, Ingo Molnar,
Borislav Petkov, Dave Hansen, H. Peter Anvin, Stefano Stabellini,
Oleksandr Tyshchenko, xen-devel
Use an x86-specific virtio_check_mem_acc_cb() for Xen in order to setup
the correct DMA ops.
Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- add missing PV check in xen_virtio_mem_acc() (Oleksandr Tyshchenko)
- add xen_virtio_restricted_mem_acc() stub (Oleksandr Tyshchenko)
---
arch/x86/xen/enlighten_hvm.c | 2 +-
arch/x86/xen/enlighten_pv.c | 2 +-
drivers/xen/grant-dma-ops.c | 12 +++++++++++-
include/xen/xen-ops.h | 6 ++++++
4 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 1c1ac418484b..c1cd28e915a3 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -212,7 +212,7 @@ static void __init xen_hvm_guest_init(void)
return;
if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
- virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
+ virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
init_hvm_pv_info();
diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 9b1a58dda935..45b24c1b646a 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c
@@ -112,7 +112,7 @@ static void __init xen_pv_init_platform(void)
{
/* PV guests can't operate virtio devices without grants. */
if (IS_ENABLED(CONFIG_XEN_VIRTIO))
- virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
+ virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP));
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index c703b77b33c9..63c3f0dac066 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -297,7 +297,7 @@ bool xen_is_grant_dma_device(struct device *dev)
bool xen_virtio_mem_acc(struct virtio_device *dev)
{
- if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
+ if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain())
return true;
return xen_is_grant_dma_device(dev->dev.parent);
@@ -372,6 +372,16 @@ void xen_grant_setup_dma_ops(struct device *dev)
dev_err(dev, "Cannot set up Xen grant DMA ops, retain platform DMA ops\n");
}
+bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
+{
+ bool ret = xen_virtio_mem_acc(dev);
+
+ if (ret)
+ xen_grant_setup_dma_ops(dev->dev.parent);
+
+ return ret;
+}
+
MODULE_DESCRIPTION("Xen grant DMA-mapping layer");
MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
MODULE_LICENSE("GPL");
diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
index dae0f350c678..a34f4271a2e9 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h
@@ -219,6 +219,7 @@ static inline void xen_preemptible_hcall_end(void) { }
void xen_grant_setup_dma_ops(struct device *dev);
bool xen_is_grant_dma_device(struct device *dev);
bool xen_virtio_mem_acc(struct virtio_device *dev);
+bool xen_virtio_restricted_mem_acc(struct virtio_device *dev);
#else
static inline void xen_grant_setup_dma_ops(struct device *dev)
{
@@ -234,6 +235,11 @@ static inline bool xen_virtio_mem_acc(struct virtio_device *dev)
{
return false;
}
+
+static inline bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
+{
+ return false;
+}
#endif /* CONFIG_XEN_GRANT_DMA_OPS */
#endif /* INCLUDE_XEN_OPS_H */
--
2.35.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86
2022-10-07 6:41 ` [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86 Juergen Gross
@ 2022-10-07 14:00 ` Oleksandr Tyshchenko
2022-10-07 16:01 ` Boris Ostrovsky
0 siblings, 1 reply; 6+ messages in thread
From: Oleksandr Tyshchenko @ 2022-10-07 14:00 UTC (permalink / raw)
To: Juergen Gross, linux-kernel, x86
Cc: Boris Ostrovsky, Thomas Gleixner, Ingo Molnar, Borislav Petkov,
Dave Hansen, H. Peter Anvin, Stefano Stabellini, xen-devel
On 07.10.22 09:41, Juergen Gross wrote:
Hello Juergen
> Use an x86-specific virtio_check_mem_acc_cb() for Xen in order to setup
> the correct DMA ops.
>
> Signed-off-by: Juergen Gross <jgross@suse.com>
> ---
> V2:
> - add missing PV check in xen_virtio_mem_acc() (Oleksandr Tyshchenko)
> - add xen_virtio_restricted_mem_acc() stub (Oleksandr Tyshchenko)
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> #
common code
> ---
> arch/x86/xen/enlighten_hvm.c | 2 +-
> arch/x86/xen/enlighten_pv.c | 2 +-
> drivers/xen/grant-dma-ops.c | 12 +++++++++++-
> include/xen/xen-ops.h | 6 ++++++
> 4 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
> index 1c1ac418484b..c1cd28e915a3 100644
> --- a/arch/x86/xen/enlighten_hvm.c
> +++ b/arch/x86/xen/enlighten_hvm.c
> @@ -212,7 +212,7 @@ static void __init xen_hvm_guest_init(void)
> return;
>
> if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
> - virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
> + virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
>
> init_hvm_pv_info();
>
> diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
> index 9b1a58dda935..45b24c1b646a 100644
> --- a/arch/x86/xen/enlighten_pv.c
> +++ b/arch/x86/xen/enlighten_pv.c
> @@ -112,7 +112,7 @@ static void __init xen_pv_init_platform(void)
> {
> /* PV guests can't operate virtio devices without grants. */
> if (IS_ENABLED(CONFIG_XEN_VIRTIO))
> - virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
> + virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
>
> populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP));
>
> diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
> index c703b77b33c9..63c3f0dac066 100644
> --- a/drivers/xen/grant-dma-ops.c
> +++ b/drivers/xen/grant-dma-ops.c
> @@ -297,7 +297,7 @@ bool xen_is_grant_dma_device(struct device *dev)
>
> bool xen_virtio_mem_acc(struct virtio_device *dev)
> {
> - if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
> + if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain())
> return true;
>
> return xen_is_grant_dma_device(dev->dev.parent);
> @@ -372,6 +372,16 @@ void xen_grant_setup_dma_ops(struct device *dev)
> dev_err(dev, "Cannot set up Xen grant DMA ops, retain platform DMA ops\n");
> }
>
> +bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
> +{
> + bool ret = xen_virtio_mem_acc(dev);
> +
> + if (ret)
> + xen_grant_setup_dma_ops(dev->dev.parent);
> +
> + return ret;
> +}
> +
> MODULE_DESCRIPTION("Xen grant DMA-mapping layer");
> MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
> MODULE_LICENSE("GPL");
> diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
> index dae0f350c678..a34f4271a2e9 100644
> --- a/include/xen/xen-ops.h
> +++ b/include/xen/xen-ops.h
> @@ -219,6 +219,7 @@ static inline void xen_preemptible_hcall_end(void) { }
> void xen_grant_setup_dma_ops(struct device *dev);
> bool xen_is_grant_dma_device(struct device *dev);
> bool xen_virtio_mem_acc(struct virtio_device *dev);
> +bool xen_virtio_restricted_mem_acc(struct virtio_device *dev);
> #else
> static inline void xen_grant_setup_dma_ops(struct device *dev)
> {
> @@ -234,6 +235,11 @@ static inline bool xen_virtio_mem_acc(struct virtio_device *dev)
> {
> return false;
> }
> +
> +static inline bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
> +{
> + return false;
> +}
> #endif /* CONFIG_XEN_GRANT_DMA_OPS */
>
> #endif /* INCLUDE_XEN_OPS_H */
--
Regards,
Oleksandr Tyshchenko
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH v2 3/3] xen/virtio: enable grant based virtio on x86
2022-10-07 14:00 ` Oleksandr Tyshchenko
@ 2022-10-07 16:01 ` Boris Ostrovsky
0 siblings, 0 replies; 6+ messages in thread
From: Boris Ostrovsky @ 2022-10-07 16:01 UTC (permalink / raw)
To: Oleksandr Tyshchenko, Juergen Gross, linux-kernel, x86
Cc: Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen,
H. Peter Anvin, Stefano Stabellini, xen-devel
On 10/7/22 10:00 AM, Oleksandr Tyshchenko wrote:
> On 07.10.22 09:41, Juergen Gross wrote:
>
> Hello Juergen
>
>> Use an x86-specific virtio_check_mem_acc_cb() for Xen in order to setup
>> the correct DMA ops.
>>
>> Signed-off-by: Juergen Gross <jgross@suse.com>
>> ---
>> V2:
>> - add missing PV check in xen_virtio_mem_acc() (Oleksandr Tyshchenko)
>> - add xen_virtio_restricted_mem_acc() stub (Oleksandr Tyshchenko)
>
> Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> #
> common code
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
^ permalink raw reply [flat|nested] 6+ messages in thread