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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 00E92C43331 for ; Wed, 1 Apr 2020 05:32:38 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CDAFE20772 for ; Wed, 1 Apr 2020 05:32:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDAFE20772 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id 7739110FC3BB9; Tue, 31 Mar 2020 22:33:27 -0700 (PDT) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=aneesh.kumar@linux.ibm.com; receiver= Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 41F6510FC3363 for ; Tue, 31 Mar 2020 22:33:25 -0700 (PDT) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 0315VeN6032356; Wed, 1 Apr 2020 01:32:34 -0400 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0b-001b2d01.pphosted.com with ESMTP id 303uj40tnx-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 01 Apr 2020 01:32:34 -0400 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 0315VFW4000555; Wed, 1 Apr 2020 05:32:34 GMT Received: from b01cxnp23034.gho.pok.ibm.com (b01cxnp23034.gho.pok.ibm.com [9.57.198.29]) by ppma04wdc.us.ibm.com with ESMTP id 301x76pfwy-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 01 Apr 2020 05:32:34 +0000 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0315WWL349742310 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 1 Apr 2020 05:32:32 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 80302AC05E; Wed, 1 Apr 2020 05:32:32 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5CF08AC059; Wed, 1 Apr 2020 05:32:30 +0000 (GMT) Received: from skywalker.linux.ibm.com (unknown [9.85.70.197]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 1 Apr 2020 05:32:30 +0000 (GMT) X-Mailer: emacs 27.0.90 (via feedmail 11-beta-1 I) From: "Aneesh Kumar K.V" To: Vaibhav Jain , linuxppc-dev@lists.ozlabs.org, linux-nvdimm@lists.01.org Subject: Re: [PATCH v5 3/4] powerpc/papr_scm,uapi: Add support for handling PAPR DSM commands In-Reply-To: <20200331143229.306718-4-vaibhav@linux.ibm.com> References: <20200331143229.306718-1-vaibhav@linux.ibm.com> <20200331143229.306718-4-vaibhav@linux.ibm.com> Date: Wed, 01 Apr 2020 11:02:28 +0530 Message-ID: <87r1x7lqj7.fsf@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.676 definitions=2020-03-31_07:2020-03-31,2020-03-31 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 impostorscore=0 adultscore=0 mlxlogscore=999 lowpriorityscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 phishscore=0 clxscore=1015 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004010044 Message-ID-Hash: 3LOBHYK2TBIFU7JG6JOBJPP6G2NO4WLD X-Message-ID-Hash: 3LOBHYK2TBIFU7JG6JOBJPP6G2NO4WLD X-MailFrom: aneesh.kumar@linux.ibm.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Vaibhav Jain , Michael Ellerman , Alastair D'Silva X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Vaibhav Jain writes: > Implement support for handling PAPR DSM commands in papr_scm > module. We advertise support for ND_CMD_CALL for the dimm command mask > and implement necessary scaffolding in the module to handle ND_CMD_CALL > ioctl and DSM commands that we receive. > > The layout of the DSM commands as we expect from libnvdimm/libndctl is > described in newly introduced uapi header 'papr_scm_dsm.h' which > defines a new 'struct nd_papr_scm_cmd_pkg' header. This header is used > to communicate the DSM command via 'nd_pkg_papr_scm->nd_command' and > size of payload that need to be sent/received for servicing the DSM. > > The PAPR DSM commands are assigned indexes started from 0x10000 to > prevent them from overlapping ND_CMD_* values and also makes handling > dimm commands in papr_scm_ndctl(). A new function cmd_to_func() is > implemented that reads the args to papr_scm_ndctl() and performs > sanity tests on them. In case of a DSM command being sent via > ND_CMD_CALL a newly introduced function papr_scm_service_dsm() is > called to handle the request. > Reviewed-by: Aneesh Kumar K.V > Signed-off-by: Vaibhav Jain > > --- > Changelog: > > v4..v5: Fixed a bug in new implementation of papr_scm_ndctl(). > > v3..v4: Updated papr_scm_ndctl() to delegate DSM command handling to a > different function papr_scm_service_dsm(). [Aneesh] > > v2..v3: Updated the nd_papr_scm_cmd_pkg to use __xx types as its > exported to the userspace [Aneesh] > > v1..v2: New patch in the series. > --- > arch/powerpc/include/uapi/asm/papr_scm_dsm.h | 161 +++++++++++++++++++ > arch/powerpc/platforms/pseries/papr_scm.c | 97 ++++++++++- > 2 files changed, 252 insertions(+), 6 deletions(-) > create mode 100644 arch/powerpc/include/uapi/asm/papr_scm_dsm.h > > diff --git a/arch/powerpc/include/uapi/asm/papr_scm_dsm.h b/arch/powerpc/include/uapi/asm/papr_scm_dsm.h > new file mode 100644 > index 000000000000..c039a49b41b4 > --- /dev/null > +++ b/arch/powerpc/include/uapi/asm/papr_scm_dsm.h > @@ -0,0 +1,161 @@ > +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ > +/* > + * PAPR SCM Device specific methods and struct for libndctl and ndctl > + * > + * (C) Copyright IBM 2020 > + * > + * Author: Vaibhav Jain > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#ifndef _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ > +#define _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ > + > +#include > + > +#ifdef __KERNEL__ > +#include > +#else > +#include > +#endif > + > +/* > + * DSM Envelope: > + * > + * The ioctl ND_CMD_CALL transfers data between user-space and kernel via > + * 'envelopes' which consists of a header and user-defined payload sections. > + * The header is described by 'struct nd_papr_scm_cmd_pkg' which expects a > + * payload following it and offset of which relative to the struct is provided > + * by 'nd_papr_scm_cmd_pkg.payload_offset'. * > + * > + * +-------------+---------------------+---------------------------+ > + * | 64-Bytes | 8-Bytes | Max 184-Bytes | > + * +-------------+---------------------+---------------------------+ > + * | nd_papr_scm_cmd_pkg | | > + * |-------------+ | | > + * | nd_cmd_pkg | | | > + * +-------------+---------------------+---------------------------+ > + * | nd_family | | | > + * | nd_size_out | cmd_status | | > + * | nd_size_in | payload_version | PAYLOAD | > + * | nd_command | payload_offset -----> | > + * | nd_fw_size | | | > + * +-------------+---------------------+---------------------------+ > + * > + * DSM Header: > + * > + * The header is defined as 'struct nd_papr_scm_cmd_pkg' which embeds a > + * 'struct nd_cmd_pkg' instance. The DSM command is assigned to member > + * 'nd_cmd_pkg.nd_command'. Apart from size information of the envelop which is > + * contained in 'struct nd_cmd_pkg', the header also has members following > + * members: > + * > + * 'cmd_status' : (Out) Errors if any encountered while servicing DSM. > + * 'payload_version' : (In/Out) Version number associated with the payload. > + * 'payload_offset' : (In)Relative offset of payload from start of envelope. > + * > + * DSM Payload: > + * > + * The layout of the DSM Payload is defined by various structs shared between > + * papr_scm and libndctl so that contents of payload can be interpreted. During > + * servicing of a DSM the papr_scm module will read input args from the payload > + * field by casting its contents to an appropriate struct pointer based on the > + * DSM command. Similarly the output of servicing the DSM command will be copied > + * to the payload field using the same struct. > + * > + * 'libnvdimm' enforces a hard limit of 256 bytes on the envelope size, which > + * leaves around 184 bytes for the envelope payload (ignoring any padding that > + * the compiler may silently introduce). > + * > + * Payload Version: > + * > + * A 'payload_version' field is present in DSM header that indicates a specific > + * version of the structure present in DSM Payload for a given DSM command. This > + * provides backward compatibility in case the DSM Payload structure evolves > + * and different structures are supported by 'papr_scm' and 'libndctl'. > + * > + * When sending a DSM Payload to 'papr_scm', 'libndctl' should send the version > + * of the payload struct it supports via 'payload_version' field. The 'papr_scm' > + * module when servicing the DSM envelop checks the 'payload_version' and then > + * uses 'payload struct version' == MIN('payload_version field', > + * 'max payload-struct-version supported by papr_scm') to service the DSM. After > + * servicing the DSM, 'papr_scm' put the negotiated version of payload struct in > + * returned 'payload_version' field. > + * > + * Libndctl on receiving the envelop back from papr_scm again checks the > + * 'payload_version' field and based on it use the appropriate version dsm > + * struct to parse the results. > + * > + * Backward Compatibility: > + * > + * Above scheme of exchanging different versioned DSM struct between libndctl > + * and papr_scm should provide backward compatibility until following two > + * assumptions/conditions when defining new DSM structs hold: > + * > + * Let T(X) = { set of attributes in DSM struct 'T' versioned X } > + * > + * 1. T(X) is a proper subset of T(Y) if X > Y. > + * i.e Each new version of DSM struct should retain existing struct > + * attributes from previous version > + * > + * 2. If an entity (libndctl or papr_scm) supports a DSM struct T(X) then > + * it should also support T(1), T(2)...T(X - 1). > + * i.e When adding support for new version of a DSM struct, libndctl > + * and papr_scm should retain support of the existing DSM struct > + * version they support. > + */ > + > +/* Papr-scm-header + payload expected with ND_CMD_CALL ioctl from libnvdimm */ > +struct nd_papr_scm_cmd_pkg { > + struct nd_cmd_pkg hdr; /* Package header containing sub-cmd */ > + __s32 cmd_status; /* Out: Sub-cmd status returned back */ > + __u16 payload_offset; /* In: offset from start of struct */ > + __u16 payload_version; /* In/Out: version of the payload */ > + __u8 payload[]; /* In/Out: Sub-cmd data buffer */ > +}; > + > +/* > + * Sub commands for ND_CMD_CALL. To prevent overlap from ND_CMD_*, values for > + * these enums start at 0x10000. These values are then returned from > + * cmd_to_func() making it easy to implement the switch-case block in > + * papr_scm_ndctl(). These commands are sent to the kernel via > + * 'nd_papr_scm_cmd_pkg.hdr.nd_command' > + */ > +enum dsm_papr_scm { > + DSM_PAPR_SCM_MIN = 0x10000, > + DSM_PAPR_SCM_MAX, > +}; > + > +/* Helpers to evaluate the size of PAPR_SCM envelope */ > +/* Calculate the papr_scm-header size */ > +#define ND_PAPR_SCM_ENVELOPE_CONTENT_HDR_SIZE \ > + (sizeof(struct nd_papr_scm_cmd_pkg) - sizeof(struct nd_cmd_pkg)) > + > +/* Given a type calculate envelope-content size (papr_scm-header + payload) */ > +#define ND_PAPR_SCM_ENVELOPE_CONTENT_SIZE(_type_) \ > + (sizeof(_type_) + ND_PAPR_SCM_ENVELOPE_CONTENT_HDR_SIZE) > + > +/* Convert a libnvdimm nd_cmd_pkg to papr_scm specific pkg */ > +static struct nd_papr_scm_cmd_pkg *nd_to_papr_cmd_pkg(struct nd_cmd_pkg *cmd) > +{ > + return (struct nd_papr_scm_cmd_pkg *) cmd; > +} > + > +/* Return the payload pointer for a given pcmd */ > +static void *papr_scm_pcmd_to_payload(struct nd_papr_scm_cmd_pkg *pcmd) > +{ > + if (pcmd->hdr.nd_size_in == 0 && pcmd->hdr.nd_size_out == 0) > + return NULL; > + else > + return (void *)((__u8 *) pcmd + pcmd->payload_offset); > +} > +#endif /* _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ */ > diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c > index aaf2e4ab1f75..e8ce96d2249e 100644 > --- a/arch/powerpc/platforms/pseries/papr_scm.c > +++ b/arch/powerpc/platforms/pseries/papr_scm.c > @@ -15,13 +15,15 @@ > > #include > #include > +#include > > #define BIND_ANY_ADDR (~0ul) > > #define PAPR_SCM_DIMM_CMD_MASK \ > ((1ul << ND_CMD_GET_CONFIG_SIZE) | \ > (1ul << ND_CMD_GET_CONFIG_DATA) | \ > - (1ul << ND_CMD_SET_CONFIG_DATA)) > + (1ul << ND_CMD_SET_CONFIG_DATA) | \ > + (1ul << ND_CMD_CALL)) > > struct papr_scm_priv { > struct platform_device *pdev; > @@ -283,15 +285,92 @@ static int papr_scm_meta_set(struct papr_scm_priv *p, > return 0; > } > > +/* > + * Validate the inputs args to dimm-control function and return '0' if valid. > + * This also does initial sanity validation to ND_CMD_CALL sub-command packages. > + */ > +static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf, > + unsigned int buf_len) > +{ > + unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK; > + struct nd_papr_scm_cmd_pkg *pkg = nd_to_papr_cmd_pkg(buf); > + > + /* Only dimm-specific calls are supported atm */ > + if (!nvdimm) > + return -EINVAL; > + > + if (!test_bit(cmd, &cmd_mask)) { > + pr_debug("%s: Unsupported cmd=%u\n", __func__, cmd); > + return -EINVAL; > + } else if (cmd == ND_CMD_CALL) { > + > + /* Verify the envelop package */ > + if (!buf || buf_len < sizeof(struct nd_papr_scm_cmd_pkg)) { > + pr_debug("%s: Invalid pkg size=%u\n", __func__, > + buf_len); > + return -EINVAL; > + } > + > + /* Verify that the DSM command family is valid */ > + if (pkg->hdr.nd_family != NVDIMM_FAMILY_PAPR_SCM) { > + pr_debug("%s: Invalid pkg family=0x%llx\n", __func__, > + pkg->hdr.nd_family); > + return -EINVAL; > + > + } > + > + /* We except a payload with all DSM commands */ > + if (papr_scm_pcmd_to_payload(pkg) == NULL) { > + pr_debug("%s: Empty payload for sub-command=0x%llx\n", > + __func__, pkg->hdr.nd_command); > + return -EINVAL; > + } > + } > + > + /* Command looks valid */ > + return 0; > +} > + > +static int papr_scm_service_dsm(struct papr_scm_priv *p, > + struct nd_papr_scm_cmd_pkg *call_pkg) > +{ > + /* unknown subcommands return error in packages */ > + if (call_pkg->hdr.nd_command <= DSM_PAPR_SCM_MIN || > + call_pkg->hdr.nd_command >= DSM_PAPR_SCM_MAX) { > + pr_debug("Invalid DSM command 0x%llx\n", > + call_pkg->hdr.nd_command); > + call_pkg->cmd_status = -EINVAL; > + return 0; > + } > + > + /* Depending on the DSM command call appropriate service routine */ > + switch (call_pkg->hdr.nd_command) { > + default: > + pr_debug("Unsupported DSM command 0x%llx\n", > + call_pkg->hdr.nd_command); > + call_pkg->cmd_status = -ENOENT; > + return 0; > + } > +} > + > int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, > unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc) > { > struct nd_cmd_get_config_size *get_size_hdr; > struct papr_scm_priv *p; > + struct nd_papr_scm_cmd_pkg *call_pkg = NULL; > + int rc; > > - /* Only dimm-specific calls are supported atm */ > - if (!nvdimm) > - return -EINVAL; > + /* Use a local variable in case cmd_rc pointer is NULL */ > + if (cmd_rc == NULL) > + cmd_rc = &rc; > + > + *cmd_rc = is_cmd_valid(nvdimm, cmd, buf, buf_len); > + if (*cmd_rc) { > + pr_debug("%s: Invalid cmd=0x%x. Err=%d\n", __func__, > + cmd, *cmd_rc); > + return *cmd_rc; > + } > > p = nvdimm_provider_data(nvdimm); > > @@ -313,13 +392,19 @@ int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, > *cmd_rc = papr_scm_meta_set(p, buf); > break; > > + case ND_CMD_CALL: > + call_pkg = nd_to_papr_cmd_pkg(buf); > + *cmd_rc = papr_scm_service_dsm(p, call_pkg); > + break; > + > default: > - return -EINVAL; > + dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd); > + *cmd_rc = -EINVAL; > } > > dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc); > > - return 0; > + return *cmd_rc; > } > > static inline int papr_scm_node(int node) > -- > 2.25.1 > _______________________________________________ > Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org > To unsubscribe send an email to linux-nvdimm-leave@lists.01.org _______________________________________________ Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org To unsubscribe send an email to linux-nvdimm-leave@lists.01.org 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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 189D2C43331 for ; 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Wed, 01 Apr 2020 05:32:34 +0000 Received: from b01ledav006.gho.pok.ibm.com (b01ledav006.gho.pok.ibm.com [9.57.199.111]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0315WWL349742310 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 1 Apr 2020 05:32:32 GMT Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 80302AC05E; Wed, 1 Apr 2020 05:32:32 +0000 (GMT) Received: from b01ledav006.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5CF08AC059; Wed, 1 Apr 2020 05:32:30 +0000 (GMT) Received: from skywalker.linux.ibm.com (unknown [9.85.70.197]) by b01ledav006.gho.pok.ibm.com (Postfix) with ESMTP; Wed, 1 Apr 2020 05:32:30 +0000 (GMT) X-Mailer: emacs 27.0.90 (via feedmail 11-beta-1 I) From: "Aneesh Kumar K.V" To: Vaibhav Jain , linuxppc-dev@lists.ozlabs.org, linux-nvdimm@lists.01.org Subject: Re: [PATCH v5 3/4] powerpc/papr_scm,uapi: Add support for handling PAPR DSM commands In-Reply-To: <20200331143229.306718-4-vaibhav@linux.ibm.com> References: <20200331143229.306718-1-vaibhav@linux.ibm.com> <20200331143229.306718-4-vaibhav@linux.ibm.com> Date: Wed, 01 Apr 2020 11:02:28 +0530 Message-ID: <87r1x7lqj7.fsf@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138, 18.0.676 definitions=2020-03-31_07:2020-03-31, 2020-03-31 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 impostorscore=0 adultscore=0 mlxlogscore=999 lowpriorityscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 phishscore=0 clxscore=1015 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004010044 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: , Cc: Vaibhav Jain , Michael Ellerman , Alastair D'Silva Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Vaibhav Jain writes: > Implement support for handling PAPR DSM commands in papr_scm > module. We advertise support for ND_CMD_CALL for the dimm command mask > and implement necessary scaffolding in the module to handle ND_CMD_CALL > ioctl and DSM commands that we receive. > > The layout of the DSM commands as we expect from libnvdimm/libndctl is > described in newly introduced uapi header 'papr_scm_dsm.h' which > defines a new 'struct nd_papr_scm_cmd_pkg' header. This header is used > to communicate the DSM command via 'nd_pkg_papr_scm->nd_command' and > size of payload that need to be sent/received for servicing the DSM. > > The PAPR DSM commands are assigned indexes started from 0x10000 to > prevent them from overlapping ND_CMD_* values and also makes handling > dimm commands in papr_scm_ndctl(). A new function cmd_to_func() is > implemented that reads the args to papr_scm_ndctl() and performs > sanity tests on them. In case of a DSM command being sent via > ND_CMD_CALL a newly introduced function papr_scm_service_dsm() is > called to handle the request. > Reviewed-by: Aneesh Kumar K.V > Signed-off-by: Vaibhav Jain > > --- > Changelog: > > v4..v5: Fixed a bug in new implementation of papr_scm_ndctl(). > > v3..v4: Updated papr_scm_ndctl() to delegate DSM command handling to a > different function papr_scm_service_dsm(). [Aneesh] > > v2..v3: Updated the nd_papr_scm_cmd_pkg to use __xx types as its > exported to the userspace [Aneesh] > > v1..v2: New patch in the series. > --- > arch/powerpc/include/uapi/asm/papr_scm_dsm.h | 161 +++++++++++++++++++ > arch/powerpc/platforms/pseries/papr_scm.c | 97 ++++++++++- > 2 files changed, 252 insertions(+), 6 deletions(-) > create mode 100644 arch/powerpc/include/uapi/asm/papr_scm_dsm.h > > diff --git a/arch/powerpc/include/uapi/asm/papr_scm_dsm.h b/arch/powerpc/include/uapi/asm/papr_scm_dsm.h > new file mode 100644 > index 000000000000..c039a49b41b4 > --- /dev/null > +++ b/arch/powerpc/include/uapi/asm/papr_scm_dsm.h > @@ -0,0 +1,161 @@ > +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */ > +/* > + * PAPR SCM Device specific methods and struct for libndctl and ndctl > + * > + * (C) Copyright IBM 2020 > + * > + * Author: Vaibhav Jain > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2, or (at your option) > + * any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#ifndef _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ > +#define _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ > + > +#include > + > +#ifdef __KERNEL__ > +#include > +#else > +#include > +#endif > + > +/* > + * DSM Envelope: > + * > + * The ioctl ND_CMD_CALL transfers data between user-space and kernel via > + * 'envelopes' which consists of a header and user-defined payload sections. > + * The header is described by 'struct nd_papr_scm_cmd_pkg' which expects a > + * payload following it and offset of which relative to the struct is provided > + * by 'nd_papr_scm_cmd_pkg.payload_offset'. * > + * > + * +-------------+---------------------+---------------------------+ > + * | 64-Bytes | 8-Bytes | Max 184-Bytes | > + * +-------------+---------------------+---------------------------+ > + * | nd_papr_scm_cmd_pkg | | > + * |-------------+ | | > + * | nd_cmd_pkg | | | > + * +-------------+---------------------+---------------------------+ > + * | nd_family | | | > + * | nd_size_out | cmd_status | | > + * | nd_size_in | payload_version | PAYLOAD | > + * | nd_command | payload_offset -----> | > + * | nd_fw_size | | | > + * +-------------+---------------------+---------------------------+ > + * > + * DSM Header: > + * > + * The header is defined as 'struct nd_papr_scm_cmd_pkg' which embeds a > + * 'struct nd_cmd_pkg' instance. The DSM command is assigned to member > + * 'nd_cmd_pkg.nd_command'. Apart from size information of the envelop which is > + * contained in 'struct nd_cmd_pkg', the header also has members following > + * members: > + * > + * 'cmd_status' : (Out) Errors if any encountered while servicing DSM. > + * 'payload_version' : (In/Out) Version number associated with the payload. > + * 'payload_offset' : (In)Relative offset of payload from start of envelope. > + * > + * DSM Payload: > + * > + * The layout of the DSM Payload is defined by various structs shared between > + * papr_scm and libndctl so that contents of payload can be interpreted. During > + * servicing of a DSM the papr_scm module will read input args from the payload > + * field by casting its contents to an appropriate struct pointer based on the > + * DSM command. Similarly the output of servicing the DSM command will be copied > + * to the payload field using the same struct. > + * > + * 'libnvdimm' enforces a hard limit of 256 bytes on the envelope size, which > + * leaves around 184 bytes for the envelope payload (ignoring any padding that > + * the compiler may silently introduce). > + * > + * Payload Version: > + * > + * A 'payload_version' field is present in DSM header that indicates a specific > + * version of the structure present in DSM Payload for a given DSM command. This > + * provides backward compatibility in case the DSM Payload structure evolves > + * and different structures are supported by 'papr_scm' and 'libndctl'. > + * > + * When sending a DSM Payload to 'papr_scm', 'libndctl' should send the version > + * of the payload struct it supports via 'payload_version' field. The 'papr_scm' > + * module when servicing the DSM envelop checks the 'payload_version' and then > + * uses 'payload struct version' == MIN('payload_version field', > + * 'max payload-struct-version supported by papr_scm') to service the DSM. After > + * servicing the DSM, 'papr_scm' put the negotiated version of payload struct in > + * returned 'payload_version' field. > + * > + * Libndctl on receiving the envelop back from papr_scm again checks the > + * 'payload_version' field and based on it use the appropriate version dsm > + * struct to parse the results. > + * > + * Backward Compatibility: > + * > + * Above scheme of exchanging different versioned DSM struct between libndctl > + * and papr_scm should provide backward compatibility until following two > + * assumptions/conditions when defining new DSM structs hold: > + * > + * Let T(X) = { set of attributes in DSM struct 'T' versioned X } > + * > + * 1. T(X) is a proper subset of T(Y) if X > Y. > + * i.e Each new version of DSM struct should retain existing struct > + * attributes from previous version > + * > + * 2. If an entity (libndctl or papr_scm) supports a DSM struct T(X) then > + * it should also support T(1), T(2)...T(X - 1). > + * i.e When adding support for new version of a DSM struct, libndctl > + * and papr_scm should retain support of the existing DSM struct > + * version they support. > + */ > + > +/* Papr-scm-header + payload expected with ND_CMD_CALL ioctl from libnvdimm */ > +struct nd_papr_scm_cmd_pkg { > + struct nd_cmd_pkg hdr; /* Package header containing sub-cmd */ > + __s32 cmd_status; /* Out: Sub-cmd status returned back */ > + __u16 payload_offset; /* In: offset from start of struct */ > + __u16 payload_version; /* In/Out: version of the payload */ > + __u8 payload[]; /* In/Out: Sub-cmd data buffer */ > +}; > + > +/* > + * Sub commands for ND_CMD_CALL. To prevent overlap from ND_CMD_*, values for > + * these enums start at 0x10000. These values are then returned from > + * cmd_to_func() making it easy to implement the switch-case block in > + * papr_scm_ndctl(). These commands are sent to the kernel via > + * 'nd_papr_scm_cmd_pkg.hdr.nd_command' > + */ > +enum dsm_papr_scm { > + DSM_PAPR_SCM_MIN = 0x10000, > + DSM_PAPR_SCM_MAX, > +}; > + > +/* Helpers to evaluate the size of PAPR_SCM envelope */ > +/* Calculate the papr_scm-header size */ > +#define ND_PAPR_SCM_ENVELOPE_CONTENT_HDR_SIZE \ > + (sizeof(struct nd_papr_scm_cmd_pkg) - sizeof(struct nd_cmd_pkg)) > + > +/* Given a type calculate envelope-content size (papr_scm-header + payload) */ > +#define ND_PAPR_SCM_ENVELOPE_CONTENT_SIZE(_type_) \ > + (sizeof(_type_) + ND_PAPR_SCM_ENVELOPE_CONTENT_HDR_SIZE) > + > +/* Convert a libnvdimm nd_cmd_pkg to papr_scm specific pkg */ > +static struct nd_papr_scm_cmd_pkg *nd_to_papr_cmd_pkg(struct nd_cmd_pkg *cmd) > +{ > + return (struct nd_papr_scm_cmd_pkg *) cmd; > +} > + > +/* Return the payload pointer for a given pcmd */ > +static void *papr_scm_pcmd_to_payload(struct nd_papr_scm_cmd_pkg *pcmd) > +{ > + if (pcmd->hdr.nd_size_in == 0 && pcmd->hdr.nd_size_out == 0) > + return NULL; > + else > + return (void *)((__u8 *) pcmd + pcmd->payload_offset); > +} > +#endif /* _UAPI_ASM_POWERPC_PAPR_SCM_DSM_H_ */ > diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c > index aaf2e4ab1f75..e8ce96d2249e 100644 > --- a/arch/powerpc/platforms/pseries/papr_scm.c > +++ b/arch/powerpc/platforms/pseries/papr_scm.c > @@ -15,13 +15,15 @@ > > #include > #include > +#include > > #define BIND_ANY_ADDR (~0ul) > > #define PAPR_SCM_DIMM_CMD_MASK \ > ((1ul << ND_CMD_GET_CONFIG_SIZE) | \ > (1ul << ND_CMD_GET_CONFIG_DATA) | \ > - (1ul << ND_CMD_SET_CONFIG_DATA)) > + (1ul << ND_CMD_SET_CONFIG_DATA) | \ > + (1ul << ND_CMD_CALL)) > > struct papr_scm_priv { > struct platform_device *pdev; > @@ -283,15 +285,92 @@ static int papr_scm_meta_set(struct papr_scm_priv *p, > return 0; > } > > +/* > + * Validate the inputs args to dimm-control function and return '0' if valid. > + * This also does initial sanity validation to ND_CMD_CALL sub-command packages. > + */ > +static int is_cmd_valid(struct nvdimm *nvdimm, unsigned int cmd, void *buf, > + unsigned int buf_len) > +{ > + unsigned long cmd_mask = PAPR_SCM_DIMM_CMD_MASK; > + struct nd_papr_scm_cmd_pkg *pkg = nd_to_papr_cmd_pkg(buf); > + > + /* Only dimm-specific calls are supported atm */ > + if (!nvdimm) > + return -EINVAL; > + > + if (!test_bit(cmd, &cmd_mask)) { > + pr_debug("%s: Unsupported cmd=%u\n", __func__, cmd); > + return -EINVAL; > + } else if (cmd == ND_CMD_CALL) { > + > + /* Verify the envelop package */ > + if (!buf || buf_len < sizeof(struct nd_papr_scm_cmd_pkg)) { > + pr_debug("%s: Invalid pkg size=%u\n", __func__, > + buf_len); > + return -EINVAL; > + } > + > + /* Verify that the DSM command family is valid */ > + if (pkg->hdr.nd_family != NVDIMM_FAMILY_PAPR_SCM) { > + pr_debug("%s: Invalid pkg family=0x%llx\n", __func__, > + pkg->hdr.nd_family); > + return -EINVAL; > + > + } > + > + /* We except a payload with all DSM commands */ > + if (papr_scm_pcmd_to_payload(pkg) == NULL) { > + pr_debug("%s: Empty payload for sub-command=0x%llx\n", > + __func__, pkg->hdr.nd_command); > + return -EINVAL; > + } > + } > + > + /* Command looks valid */ > + return 0; > +} > + > +static int papr_scm_service_dsm(struct papr_scm_priv *p, > + struct nd_papr_scm_cmd_pkg *call_pkg) > +{ > + /* unknown subcommands return error in packages */ > + if (call_pkg->hdr.nd_command <= DSM_PAPR_SCM_MIN || > + call_pkg->hdr.nd_command >= DSM_PAPR_SCM_MAX) { > + pr_debug("Invalid DSM command 0x%llx\n", > + call_pkg->hdr.nd_command); > + call_pkg->cmd_status = -EINVAL; > + return 0; > + } > + > + /* Depending on the DSM command call appropriate service routine */ > + switch (call_pkg->hdr.nd_command) { > + default: > + pr_debug("Unsupported DSM command 0x%llx\n", > + call_pkg->hdr.nd_command); > + call_pkg->cmd_status = -ENOENT; > + return 0; > + } > +} > + > int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, > unsigned int cmd, void *buf, unsigned int buf_len, int *cmd_rc) > { > struct nd_cmd_get_config_size *get_size_hdr; > struct papr_scm_priv *p; > + struct nd_papr_scm_cmd_pkg *call_pkg = NULL; > + int rc; > > - /* Only dimm-specific calls are supported atm */ > - if (!nvdimm) > - return -EINVAL; > + /* Use a local variable in case cmd_rc pointer is NULL */ > + if (cmd_rc == NULL) > + cmd_rc = &rc; > + > + *cmd_rc = is_cmd_valid(nvdimm, cmd, buf, buf_len); > + if (*cmd_rc) { > + pr_debug("%s: Invalid cmd=0x%x. Err=%d\n", __func__, > + cmd, *cmd_rc); > + return *cmd_rc; > + } > > p = nvdimm_provider_data(nvdimm); > > @@ -313,13 +392,19 @@ int papr_scm_ndctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, > *cmd_rc = papr_scm_meta_set(p, buf); > break; > > + case ND_CMD_CALL: > + call_pkg = nd_to_papr_cmd_pkg(buf); > + *cmd_rc = papr_scm_service_dsm(p, call_pkg); > + break; > + > default: > - return -EINVAL; > + dev_dbg(&p->pdev->dev, "Unknown command = %d\n", cmd); > + *cmd_rc = -EINVAL; > } > > dev_dbg(&p->pdev->dev, "returned with cmd_rc = %d\n", *cmd_rc); > > - return 0; > + return *cmd_rc; > } > > static inline int papr_scm_node(int node) > -- > 2.25.1 > _______________________________________________ > Linux-nvdimm mailing list -- linux-nvdimm@lists.01.org > To unsubscribe send an email to linux-nvdimm-leave@lists.01.org