diff mbox series

[v5,16/17] crypto/nx: Get NX capabilities for GZIP coprocessor type

Message ID 726de270eb20e0898f4391a0b0e7077697db66ab.camel@linux.ibm.com (mailing list archive)
State Not Applicable
Delegated to: Herbert Xu
Headers show
Series Enable VAS and NX-GZIP support on PowerVM | expand

Commit Message

Haren Myneni June 13, 2021, 11:04 a.m. UTC 
The hypervisor provides different capabilities that it supports
to define the user space NX request. These capabilities are
recommended minimum compression / decompression lengths and the
maximum request buffer size in bytes.

Changes to get NX overall capabilities which points to the
specific features that the hypervisor supports. Then retrieve
the capabilities for the specific feature (available only
for NXGZIP).

Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/crypto/nx/nx-common-pseries.c | 86 +++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)

Comments

Nicholas Piggin June 14, 2021, 3:39 a.m. UTC | #1 
Excerpts from Haren Myneni's message of June 13, 2021 9:04 pm:
> 
> The hypervisor provides different capabilities that it supports
> to define the user space NX request. These capabilities are
> recommended minimum compression / decompression lengths and the
> maximum request buffer size in bytes.
> 
> Changes to get NX overall capabilities which points to the
> specific features that the hypervisor supports. Then retrieve
> the capabilities for the specific feature (available only
> for NXGZIP).

So what does this give you which you didn't have before? Should
this go before the previous patch that enables the interface for guests,
or is there some functional-yet-degraded mode that is available without
this patch?

I would suggest even if this is the case to switch ordering of the 
patches so as to reduce the matrix of functionality that userspace sees 
when bisecting. Unless you specifically want this kind of bisectability,
in which case make that explicit in the changelog.

Thanks,
Nick

> 
> Signed-off-by: Haren Myneni <haren@linux.ibm.com>
> Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
> ---
>  drivers/crypto/nx/nx-common-pseries.c | 86 +++++++++++++++++++++++++++
>  1 file changed, 86 insertions(+)
> 
> diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx-common-pseries.c
> index 9a40fca8a9e6..60b5049ec9f7 100644
> --- a/drivers/crypto/nx/nx-common-pseries.c
> +++ b/drivers/crypto/nx/nx-common-pseries.c
> @@ -9,6 +9,7 @@
>   */
>  
>  #include <asm/vio.h>
> +#include <asm/hvcall.h>
>  #include <asm/vas.h>
>  
>  #include "nx-842.h"
> @@ -20,6 +21,29 @@ MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
>  MODULE_ALIAS_CRYPTO("842");
>  MODULE_ALIAS_CRYPTO("842-nx");
>  
> +/*
> + * Coprocessor type specific capabilities from the hypervisor.
> + */
> +struct hv_nx_ct_caps {
> +	__be64	descriptor;
> +	__be64	req_max_processed_len;	/* Max bytes in one GZIP request */
> +	__be64	min_compress_len;	/* Min compression size in bytes */
> +	__be64	min_decompress_len;	/* Min decompression size in bytes */
> +} __packed __aligned(0x1000);
> +
> +/*
> + * Coprocessor type specific capabilities.
> + */
> +struct nx_ct_caps {
> +	u64	descriptor;
> +	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
> +	u64	min_compress_len;	/* Min compression in bytes */
> +	u64	min_decompress_len;	/* Min decompression in bytes */
> +};
> +
> +static u64 caps_feat;
> +static struct nx_ct_caps nx_ct_caps;
> +
>  static struct nx842_constraints nx842_pseries_constraints = {
>  	.alignment =	DDE_BUFFER_ALIGN,
>  	.multiple =	DDE_BUFFER_LAST_MULT,
> @@ -1066,6 +1090,64 @@ static void nx842_remove(struct vio_dev *viodev)
>  	kfree(old_devdata);
>  }
>  
> +/*
> + * Get NX capabilities from the hypervisor.
> + * Only NXGZIP capabilities are provided by the hypersvisor right
> + * now and these values are available to user space with sysfs.
> + */
> +static void __init nxct_get_capabilities(void)
> +{
> +	struct hv_vas_all_caps *hv_caps;
> +	struct hv_nx_ct_caps *hv_nxc;
> +	int rc;
> +
> +	hv_caps = kmalloc(sizeof(*hv_caps), GFP_KERNEL);
> +	if (!hv_caps)
> +		return;
> +	/*
> +	 * Get NX overall capabilities with feature type=0
> +	 */
> +	rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0,
> +					  (u64)virt_to_phys(hv_caps));
> +	if (rc)
> +		goto out;
> +
> +	caps_feat = be64_to_cpu(hv_caps->feat_type);
> +	/*
> +	 * NX-GZIP feature available
> +	 */
> +	if (caps_feat & VAS_NX_GZIP_FEAT_BIT) {
> +		hv_nxc = kmalloc(sizeof(*hv_nxc), GFP_KERNEL);
> +		if (!hv_nxc)
> +			goto out;
> +		/*
> +		 * Get capabilities for NX-GZIP feature
> +		 */
> +		rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES,
> +						  VAS_NX_GZIP_FEAT,
> +						  (u64)virt_to_phys(hv_nxc));
> +	} else {
> +		pr_err("NX-GZIP feature is not available\n");
> +		rc = -EINVAL;
> +	}
> +
> +	if (!rc) {
> +		nx_ct_caps.descriptor = be64_to_cpu(hv_nxc->descriptor);
> +		nx_ct_caps.req_max_processed_len =
> +				be64_to_cpu(hv_nxc->req_max_processed_len);
> +		nx_ct_caps.min_compress_len =
> +				be64_to_cpu(hv_nxc->min_compress_len);
> +		nx_ct_caps.min_decompress_len =
> +				be64_to_cpu(hv_nxc->min_decompress_len);
> +	} else {
> +		caps_feat = 0;
> +	}
> +
> +	kfree(hv_nxc);
> +out:
> +	kfree(hv_caps);
> +}
> +
>  static const struct vio_device_id nx842_vio_driver_ids[] = {
>  	{"ibm,compression-v1", "ibm,compression"},
>  	{"", ""},
> @@ -1093,6 +1175,10 @@ static int __init nx842_pseries_init(void)
>  		return -ENOMEM;
>  
>  	RCU_INIT_POINTER(devdata, new_devdata);
> +	/*
> +	 * Get NX capabilities from the hypervisor.
> +	 */
> +	nxct_get_capabilities();
>  
>  	ret = vio_register_driver(&nx842_vio_driver);
>  	if (ret) {
> -- 
> 2.18.2
> 
> 
>
Haren Myneni June 15, 2021, 12:01 a.m. UTC | #2 
On Mon, 2021-06-14 at 13:39 +1000, Nicholas Piggin wrote:
> Excerpts from Haren Myneni's message of June 13, 2021 9:04 pm:
> > The hypervisor provides different capabilities that it supports
> > to define the user space NX request. These capabilities are
> > recommended minimum compression / decompression lengths and the
> > maximum request buffer size in bytes.
> > 
> > Changes to get NX overall capabilities which points to the
> > specific features that the hypervisor supports. Then retrieve
> > the capabilities for the specific feature (available only
> > for NXGZIP).
> 
> So what does this give you which you didn't have before? Should
> this go before the previous patch that enables the interface for
> guests,
> or is there some functional-yet-degraded mode that is available
> without
> this patch?
> 
> I would suggest even if this is the case to switch ordering of the 
> patches so as to reduce the matrix of functionality that userspace
> sees 
> when bisecting. Unless you specifically want this kind of
> bisectability,
> in which case make that explicit in the changelog.

Thanks for your suggestions. I will incorporate them and post next
revision. 

The user space request buffer length should not be more than
req_max_processed_len (available through sysfs). Otherwise NX will
return the request with RMA_Reject. Whereasas min_compress_len and
min_decompress_len are recommended values. 

We can add this patch and the last one (crypto/nx: Add sysfs interface
to export NX capabilities) before the actual enablement ("crypto/nx:
Register and unregisterVAS interface on PowerVM""

Thanks
Haren

> 
> Thanks,
> Nick
> 
> > Signed-off-by: Haren Myneni <haren@linux.ibm.com>
> > Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
> > ---
> >  drivers/crypto/nx/nx-common-pseries.c | 86
> > +++++++++++++++++++++++++++
> >  1 file changed, 86 insertions(+)
> > 
> > diff --git a/drivers/crypto/nx/nx-common-pseries.c
> > b/drivers/crypto/nx/nx-common-pseries.c
> > index 9a40fca8a9e6..60b5049ec9f7 100644
> > --- a/drivers/crypto/nx/nx-common-pseries.c
> > +++ b/drivers/crypto/nx/nx-common-pseries.c
> > @@ -9,6 +9,7 @@
> >   */
> >  
> >  #include <asm/vio.h>
> > +#include <asm/hvcall.h>
> >  #include <asm/vas.h>
> >  
> >  #include "nx-842.h"
> > @@ -20,6 +21,29 @@ MODULE_DESCRIPTION("842 H/W Compression driver
> > for IBM Power processors");
> >  MODULE_ALIAS_CRYPTO("842");
> >  MODULE_ALIAS_CRYPTO("842-nx");
> >  
> > +/*
> > + * Coprocessor type specific capabilities from the hypervisor.
> > + */
> > +struct hv_nx_ct_caps {
> > +	__be64	descriptor;
> > +	__be64	req_max_processed_len;	/* Max bytes in one GZIP
> > request */
> > +	__be64	min_compress_len;	/* Min compression size in
> > bytes */
> > +	__be64	min_decompress_len;	/* Min decompression size
> > in bytes */
> > +} __packed __aligned(0x1000);
> > +
> > +/*
> > + * Coprocessor type specific capabilities.
> > + */
> > +struct nx_ct_caps {
> > +	u64	descriptor;
> > +	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
> > +	u64	min_compress_len;	/* Min compression in bytes */
> > +	u64	min_decompress_len;	/* Min decompression in bytes */
> > +};
> > +
> > +static u64 caps_feat;
> > +static struct nx_ct_caps nx_ct_caps;
> > +
> >  static struct nx842_constraints nx842_pseries_constraints = {
> >  	.alignment =	DDE_BUFFER_ALIGN,
> >  	.multiple =	DDE_BUFFER_LAST_MULT,
> > @@ -1066,6 +1090,64 @@ static void nx842_remove(struct vio_dev
> > *viodev)
> >  	kfree(old_devdata);
> >  }
> >  
> > +/*
> > + * Get NX capabilities from the hypervisor.
> > + * Only NXGZIP capabilities are provided by the hypersvisor right
> > + * now and these values are available to user space with sysfs.
> > + */
> > +static void __init nxct_get_capabilities(void)
> > +{
> > +	struct hv_vas_all_caps *hv_caps;
> > +	struct hv_nx_ct_caps *hv_nxc;
> > +	int rc;
> > +
> > +	hv_caps = kmalloc(sizeof(*hv_caps), GFP_KERNEL);
> > +	if (!hv_caps)
> > +		return;
> > +	/*
> > +	 * Get NX overall capabilities with feature type=0
> > +	 */
> > +	rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0,
> > +					  (u64)virt_to_phys(hv_caps));
> > +	if (rc)
> > +		goto out;
> > +
> > +	caps_feat = be64_to_cpu(hv_caps->feat_type);
> > +	/*
> > +	 * NX-GZIP feature available
> > +	 */
> > +	if (caps_feat & VAS_NX_GZIP_FEAT_BIT) {
> > +		hv_nxc = kmalloc(sizeof(*hv_nxc), GFP_KERNEL);
> > +		if (!hv_nxc)
> > +			goto out;
> > +		/*
> > +		 * Get capabilities for NX-GZIP feature
> > +		 */
> > +		rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES,
> > +						  VAS_NX_GZIP_FEAT,
> > +						  (u64)virt_to_phys(hv_
> > nxc));
> > +	} else {
> > +		pr_err("NX-GZIP feature is not available\n");
> > +		rc = -EINVAL;
> > +	}
> > +
> > +	if (!rc) {
> > +		nx_ct_caps.descriptor = be64_to_cpu(hv_nxc-
> > >descriptor);
> > +		nx_ct_caps.req_max_processed_len =
> > +				be64_to_cpu(hv_nxc-
> > >req_max_processed_len);
> > +		nx_ct_caps.min_compress_len =
> > +				be64_to_cpu(hv_nxc->min_compress_len);
> > +		nx_ct_caps.min_decompress_len =
> > +				be64_to_cpu(hv_nxc-
> > >min_decompress_len);
> > +	} else {
> > +		caps_feat = 0;
> > +	}
> > +
> > +	kfree(hv_nxc);
> > +out:
> > +	kfree(hv_caps);
> > +}
> > +
> >  static const struct vio_device_id nx842_vio_driver_ids[] = {
> >  	{"ibm,compression-v1", "ibm,compression"},
> >  	{"", ""},
> > @@ -1093,6 +1175,10 @@ static int __init nx842_pseries_init(void)
> >  		return -ENOMEM;
> >  
> >  	RCU_INIT_POINTER(devdata, new_devdata);
> > +	/*
> > +	 * Get NX capabilities from the hypervisor.
> > +	 */
> > +	nxct_get_capabilities();
> >  
> >  	ret = vio_register_driver(&nx842_vio_driver);
> >  	if (ret) {
> > -- 
> > 2.18.2
> > 
> > 
> >
diff mbox series

Patch

diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx-common-pseries.c
index 9a40fca8a9e6..60b5049ec9f7 100644
--- a/drivers/crypto/nx/nx-common-pseries.c
+++ b/drivers/crypto/nx/nx-common-pseries.c
@@ -9,6 +9,7 @@ 
  */
 
 #include <asm/vio.h>
+#include <asm/hvcall.h>
 #include <asm/vas.h>
 
 #include "nx-842.h"
@@ -20,6 +21,29 @@  MODULE_DESCRIPTION("842 H/W Compression driver for IBM Power processors");
 MODULE_ALIAS_CRYPTO("842");
 MODULE_ALIAS_CRYPTO("842-nx");
 
+/*
+ * Coprocessor type specific capabilities from the hypervisor.
+ */
+struct hv_nx_ct_caps {
+	__be64	descriptor;
+	__be64	req_max_processed_len;	/* Max bytes in one GZIP request */
+	__be64	min_compress_len;	/* Min compression size in bytes */
+	__be64	min_decompress_len;	/* Min decompression size in bytes */
+} __packed __aligned(0x1000);
+
+/*
+ * Coprocessor type specific capabilities.
+ */
+struct nx_ct_caps {
+	u64	descriptor;
+	u64	req_max_processed_len;	/* Max bytes in one GZIP request */
+	u64	min_compress_len;	/* Min compression in bytes */
+	u64	min_decompress_len;	/* Min decompression in bytes */
+};
+
+static u64 caps_feat;
+static struct nx_ct_caps nx_ct_caps;
+
 static struct nx842_constraints nx842_pseries_constraints = {
 	.alignment =	DDE_BUFFER_ALIGN,
 	.multiple =	DDE_BUFFER_LAST_MULT,
@@ -1066,6 +1090,64 @@  static void nx842_remove(struct vio_dev *viodev)
 	kfree(old_devdata);
 }
 
+/*
+ * Get NX capabilities from the hypervisor.
+ * Only NXGZIP capabilities are provided by the hypersvisor right
+ * now and these values are available to user space with sysfs.
+ */
+static void __init nxct_get_capabilities(void)
+{
+	struct hv_vas_all_caps *hv_caps;
+	struct hv_nx_ct_caps *hv_nxc;
+	int rc;
+
+	hv_caps = kmalloc(sizeof(*hv_caps), GFP_KERNEL);
+	if (!hv_caps)
+		return;
+	/*
+	 * Get NX overall capabilities with feature type=0
+	 */
+	rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0,
+					  (u64)virt_to_phys(hv_caps));
+	if (rc)
+		goto out;
+
+	caps_feat = be64_to_cpu(hv_caps->feat_type);
+	/*
+	 * NX-GZIP feature available
+	 */
+	if (caps_feat & VAS_NX_GZIP_FEAT_BIT) {
+		hv_nxc = kmalloc(sizeof(*hv_nxc), GFP_KERNEL);
+		if (!hv_nxc)
+			goto out;
+		/*
+		 * Get capabilities for NX-GZIP feature
+		 */
+		rc = h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES,
+						  VAS_NX_GZIP_FEAT,
+						  (u64)virt_to_phys(hv_nxc));
+	} else {
+		pr_err("NX-GZIP feature is not available\n");
+		rc = -EINVAL;
+	}
+
+	if (!rc) {
+		nx_ct_caps.descriptor = be64_to_cpu(hv_nxc->descriptor);
+		nx_ct_caps.req_max_processed_len =
+				be64_to_cpu(hv_nxc->req_max_processed_len);
+		nx_ct_caps.min_compress_len =
+				be64_to_cpu(hv_nxc->min_compress_len);
+		nx_ct_caps.min_decompress_len =
+				be64_to_cpu(hv_nxc->min_decompress_len);
+	} else {
+		caps_feat = 0;
+	}
+
+	kfree(hv_nxc);
+out:
+	kfree(hv_caps);
+}
+
 static const struct vio_device_id nx842_vio_driver_ids[] = {
 	{"ibm,compression-v1", "ibm,compression"},
 	{"", ""},
@@ -1093,6 +1175,10 @@  static int __init nx842_pseries_init(void)
 		return -ENOMEM;
 
 	RCU_INIT_POINTER(devdata, new_devdata);
+	/*
+	 * Get NX capabilities from the hypervisor.
+	 */
+	nxct_get_capabilities();
 
 	ret = vio_register_driver(&nx842_vio_driver);
 	if (ret) {