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[60.242.147.73]) by smtp.gmail.com with ESMTPSA id t5sm5882620pfe.116.2021.06.17.16.36.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Jun 2021 16:36:04 -0700 (PDT) Date: Fri, 18 Jun 2021 09:35:59 +1000 From: Nicholas Piggin Subject: Re: [PATCH v6 15/17] crypto/nx: Get NX capabilities for GZIP coprocessor type To: Haren Myneni , herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au Cc: haren@us.ibm.com, hbabu@us.ibm.com References: <827bf56dce09620ebecd8a00a5f97105187a6205.camel@linux.ibm.com> In-Reply-To: MIME-Version: 1.0 Message-Id: <1623972924.juhnvnlfsg.astroid@bobo.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Excerpts from Haren Myneni's message of June 18, 2021 6:38 am: >=20 > The hypervisor provides different NX capabilities that it > supports. These capabilities such as recommended minimum > compression / decompression lengths and the maximum request > buffer size in bytes are used to define the user space NX > request. >=20 > NX will reject the request if the buffer size is more than > the maximum buffer size. Whereas compression / decompression > lengths are recommended values for better performance. >=20 > 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). >=20 > Signed-off-by: Haren Myneni > Acked-by: Herbert Xu Acked-by: Nicholas Piggin > --- > drivers/crypto/nx/nx-common-pseries.c | 87 +++++++++++++++++++++++++++ > 1 file changed, 87 insertions(+) >=20 > diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx= -common-pseries.c > index cc8dd3072b8b..9fc2abb56019 100644 > --- a/drivers/crypto/nx/nx-common-pseries.c > +++ b/drivers/crypto/nx/nx-common-pseries.c > @@ -9,6 +9,8 @@ > */ > =20 > #include > +#include > +#include > =20 > #include "nx-842.h" > #include "nx_csbcpb.h" /* struct nx_csbcpb */ > @@ -19,6 +21,29 @@ MODULE_DESCRIPTION("842 H/W Compression driver for IBM= Power processors"); > MODULE_ALIAS_CRYPTO("842"); > MODULE_ALIAS_CRYPTO("842-nx"); > =20 > +/* > + * Coprocessor type specific capabilities from the hypervisor. > + */ > +struct hv_nx_cop_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_cop_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_cop_caps nx_cop_caps; > + > static struct nx842_constraints nx842_pseries_constraints =3D { > .alignment =3D DDE_BUFFER_ALIGN, > .multiple =3D DDE_BUFFER_LAST_MULT, > @@ -1065,6 +1090,64 @@ static void nx842_remove(struct vio_dev *viodev) > kfree(old_devdata); > } > =20 > +/* > + * 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 nxcop_get_capabilities(void) > +{ > + struct hv_vas_all_caps *hv_caps; > + struct hv_nx_cop_caps *hv_nxc; > + int rc; > + > + hv_caps =3D kmalloc(sizeof(*hv_caps), GFP_KERNEL); > + if (!hv_caps) > + return; > + /* > + * Get NX overall capabilities with feature type=3D0 > + */ > + rc =3D h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0, > + (u64)virt_to_phys(hv_caps)); > + if (rc) > + goto out; > + > + caps_feat =3D be64_to_cpu(hv_caps->feat_type); > + /* > + * NX-GZIP feature available > + */ > + if (caps_feat & VAS_NX_GZIP_FEAT_BIT) { > + hv_nxc =3D kmalloc(sizeof(*hv_nxc), GFP_KERNEL); > + if (!hv_nxc) > + goto out; > + /* > + * Get capabilities for NX-GZIP feature > + */ > + rc =3D 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 =3D -EINVAL; > + } > + > + if (!rc) { > + nx_cop_caps.descriptor =3D be64_to_cpu(hv_nxc->descriptor); > + nx_cop_caps.req_max_processed_len =3D > + be64_to_cpu(hv_nxc->req_max_processed_len); > + nx_cop_caps.min_compress_len =3D > + be64_to_cpu(hv_nxc->min_compress_len); > + nx_cop_caps.min_decompress_len =3D > + be64_to_cpu(hv_nxc->min_decompress_len); > + } else { > + caps_feat =3D 0; > + } > + > + kfree(hv_nxc); > +out: > + kfree(hv_caps); > +} > + > static const struct vio_device_id nx842_vio_driver_ids[] =3D { > {"ibm,compression-v1", "ibm,compression"}, > {"", ""}, > @@ -1092,6 +1175,10 @@ static int __init nx842_pseries_init(void) > return -ENOMEM; > =20 > RCU_INIT_POINTER(devdata, new_devdata); > + /* > + * Get NX capabilities from the hypervisor. > + */ > + nxcop_get_capabilities(); > =20 > ret =3D vio_register_driver(&nx842_vio_driver); > if (ret) { > --=20 > 2.18.2 >=20 >=20 >=20 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EF20C49361 for ; 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[60.242.147.73]) by smtp.gmail.com with ESMTPSA id t5sm5882620pfe.116.2021.06.17.16.36.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Jun 2021 16:36:04 -0700 (PDT) Date: Fri, 18 Jun 2021 09:35:59 +1000 From: Nicholas Piggin Subject: Re: [PATCH v6 15/17] crypto/nx: Get NX capabilities for GZIP coprocessor type To: Haren Myneni , herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au References: <827bf56dce09620ebecd8a00a5f97105187a6205.camel@linux.ibm.com> In-Reply-To: MIME-Version: 1.0 Message-Id: <1623972924.juhnvnlfsg.astroid@bobo.none> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Excerpts from Haren Myneni's message of June 18, 2021 6:38 am: >=20 > The hypervisor provides different NX capabilities that it > supports. These capabilities such as recommended minimum > compression / decompression lengths and the maximum request > buffer size in bytes are used to define the user space NX > request. >=20 > NX will reject the request if the buffer size is more than > the maximum buffer size. Whereas compression / decompression > lengths are recommended values for better performance. >=20 > 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). >=20 > Signed-off-by: Haren Myneni > Acked-by: Herbert Xu Acked-by: Nicholas Piggin > --- > drivers/crypto/nx/nx-common-pseries.c | 87 +++++++++++++++++++++++++++ > 1 file changed, 87 insertions(+) >=20 > diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx= -common-pseries.c > index cc8dd3072b8b..9fc2abb56019 100644 > --- a/drivers/crypto/nx/nx-common-pseries.c > +++ b/drivers/crypto/nx/nx-common-pseries.c > @@ -9,6 +9,8 @@ > */ > =20 > #include > +#include > +#include > =20 > #include "nx-842.h" > #include "nx_csbcpb.h" /* struct nx_csbcpb */ > @@ -19,6 +21,29 @@ MODULE_DESCRIPTION("842 H/W Compression driver for IBM= Power processors"); > MODULE_ALIAS_CRYPTO("842"); > MODULE_ALIAS_CRYPTO("842-nx"); > =20 > +/* > + * Coprocessor type specific capabilities from the hypervisor. > + */ > +struct hv_nx_cop_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_cop_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_cop_caps nx_cop_caps; > + > static struct nx842_constraints nx842_pseries_constraints =3D { > .alignment =3D DDE_BUFFER_ALIGN, > .multiple =3D DDE_BUFFER_LAST_MULT, > @@ -1065,6 +1090,64 @@ static void nx842_remove(struct vio_dev *viodev) > kfree(old_devdata); > } > =20 > +/* > + * 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 nxcop_get_capabilities(void) > +{ > + struct hv_vas_all_caps *hv_caps; > + struct hv_nx_cop_caps *hv_nxc; > + int rc; > + > + hv_caps =3D kmalloc(sizeof(*hv_caps), GFP_KERNEL); > + if (!hv_caps) > + return; > + /* > + * Get NX overall capabilities with feature type=3D0 > + */ > + rc =3D h_query_vas_capabilities(H_QUERY_NX_CAPABILITIES, 0, > + (u64)virt_to_phys(hv_caps)); > + if (rc) > + goto out; > + > + caps_feat =3D be64_to_cpu(hv_caps->feat_type); > + /* > + * NX-GZIP feature available > + */ > + if (caps_feat & VAS_NX_GZIP_FEAT_BIT) { > + hv_nxc =3D kmalloc(sizeof(*hv_nxc), GFP_KERNEL); > + if (!hv_nxc) > + goto out; > + /* > + * Get capabilities for NX-GZIP feature > + */ > + rc =3D 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 =3D -EINVAL; > + } > + > + if (!rc) { > + nx_cop_caps.descriptor =3D be64_to_cpu(hv_nxc->descriptor); > + nx_cop_caps.req_max_processed_len =3D > + be64_to_cpu(hv_nxc->req_max_processed_len); > + nx_cop_caps.min_compress_len =3D > + be64_to_cpu(hv_nxc->min_compress_len); > + nx_cop_caps.min_decompress_len =3D > + be64_to_cpu(hv_nxc->min_decompress_len); > + } else { > + caps_feat =3D 0; > + } > + > + kfree(hv_nxc); > +out: > + kfree(hv_caps); > +} > + > static const struct vio_device_id nx842_vio_driver_ids[] =3D { > {"ibm,compression-v1", "ibm,compression"}, > {"", ""}, > @@ -1092,6 +1175,10 @@ static int __init nx842_pseries_init(void) > return -ENOMEM; > =20 > RCU_INIT_POINTER(devdata, new_devdata); > + /* > + * Get NX capabilities from the hypervisor. > + */ > + nxcop_get_capabilities(); > =20 > ret =3D vio_register_driver(&nx842_vio_driver); > if (ret) { > --=20 > 2.18.2 >=20 >=20 >=20