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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E2A2BCEF142 for ; Tue, 8 Oct 2024 09:28:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Wtp/4jlNl3GvCJQFywIGbHjv4GHS1wakdte/09m7HMQ=; b=agk+bMKZDnETU4AAAaHWa2xyKO UUauYmTXyIKSOLfIOkFmsU4+GDLl2ymKrdvJNc1BKVkpPwRGxGVsitAwOZY4QsBBoZ1BXeC0utwUk TA7+VeXG6UZeNkfzPDcOf9lZDvyBjMJmB/S8pWgzaXP1NDx1o2wVXydW9jvyDtfwdgAiHR3wijAPv 7hMld1vCYeDXUTsQY5azS5L7aUlmzewHpuCqfwshY0GqhWhISTil0esXZOo9X0G3gbMBV+q1By/ht rOG/F2cKVQQG6UFTTnq1BMuDK/HP207nq1PQQaoWxxuxIwSfqd5u+6FEdySh4Ffzi69ukmJRsTH/b 1TaulnBA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1sy6Vm-00000005Iu9-0sBJ; Tue, 08 Oct 2024 09:28:10 +0000 Received: from out30-130.freemail.mail.aliyun.com ([115.124.30.130]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1sy6Tk-00000005Ic3-0E7E for linux-nvme@lists.infradead.org; Tue, 08 Oct 2024 09:26:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1728379561; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=Wtp/4jlNl3GvCJQFywIGbHjv4GHS1wakdte/09m7HMQ=; b=rnDbKNnrny9SxFKOUjzQ5gWiXY4P5M1kTqR8Qlj6XNEOBNcpPlWwEYkiz8yog8rk88QLZoHyWoEIVp/1jMnr/z9qNnMTxjLoKQmoYX2LbgFU5VSzYxhQ9zCtpVIYx/1P2CBPizL2mD1sPB57bnSe3D9QPd+7eLMeMHKg7m3p8Eo= Received: from 30.178.82.99(mailfrom:kanie@linux.alibaba.com fp:SMTPD_---0WGdYz3E_1728379559) by smtp.aliyun-inc.com; Tue, 08 Oct 2024 17:26:00 +0800 Message-ID: <8f971633-55a6-4a66-b24f-4e13d977856f@linux.alibaba.com> Date: Tue, 8 Oct 2024 17:25:57 +0800 MIME-Version: 1.0 User-Agent: =?UTF-8?B?TW96aWxsYSBUaHVuZGVyYmlyZCDmtYvor5XniYg=?= Subject: Re: [PATCH v11 1/1] nvmet: support reservation feature To: Dmitry Bogdanov Cc: hch@lst.de, sagi@grimberg.me, kch@nvidia.com, linux-nvme@lists.infradead.org References: <20240929031410.31281-1-kanie@linux.alibaba.com> <20240929031410.31281-2-kanie@linux.alibaba.com> <20240930125329.GI22571@yadro.com> <20241007080853.GJ22571@yadro.com> <20241008084537.GK22571@yadro.com> From: Guixin Liu In-Reply-To: <20241008084537.GK22571@yadro.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241008_022604_307295_10E760CA X-CRM114-Status: GOOD ( 21.81 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org 在 2024/10/8 16:45, Dmitry Bogdanov 写道: > On Tue, Oct 08, 2024 at 03:27:46PM +0800, Guixin Liu wrote: >> 在 2024/10/7 16:08, Dmitry Bogdanov 写道: >>> On Sat, Oct 05, 2024 at 10:26:58PM +0800, Guixin Liu wrote: >>>> 在 2024/9/30 20:53, Dmitry Bogdanov 写道: >>>>> On Sun, Sep 29, 2024 at 11:14:10AM +0800, Guixin Liu wrote: >>>>>> This patch implements the reservation feature, includes: >>>>>> 1. reservation register(register, unregister and replace). >>>>>> 2. reservation acquire(acquire, preempt, preempt and abort). >>>>>> 3. reservation release(release and clear). >>>>>> 4. reservation report. >>>>>> 5. set feature and get feature of reservation notify mask. >>>>>> 6. get log page of reservation event. >>>>>> >>>>>> And also make reservation configurable, one can set ns to support >>>>>> reservation before enable ns. The default of resv_enable is false. >>>>>> >>>>>> Signed-off-by: Guixin Liu >>>>>> --- >>>>>> + >>>>>> +static void nvmet_execute_pr_report(struct nvmet_req *req) >>>>>> +{ >>>>>> + u32 cdw11 = le32_to_cpu(req->cmd->common.cdw11); >>>>>> + u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10); >>>>>> + u32 num_bytes = 4 * (cdw10 + 1); /* cdw10 is number of dwords */ >>>>>> + u8 eds = cdw11 & 1; /* Extended data structure, bit 00 */ >>>>>> + struct nvme_registered_ctrl_ext *ctrl_eds; >>>>>> + struct nvme_reservation_status_ext *data; >>>>>> + struct nvmet_pr *pr = &req->ns->pr; >>>>>> + struct nvmet_pr_registrant *holder; >>>>>> + struct nvmet_pr_registrant *reg; >>>>>> + u16 num_ctrls = 0; >>>>>> + u16 status; >>>>>> + u8 rtype; >>>>>> + >>>>>> + /* nvmet hostid(uuid_t) is 128 bit. */ >>>>>> + if (!eds) { >>>>>> + req->error_loc = offsetof(struct nvme_common_command, cdw11); >>>>>> + status = NVME_SC_HOST_ID_INCONSIST | NVME_SC_DNR; >>>>>> + goto out; >>>>>> + } >>>>>> + >>>>>> + if (num_bytes < sizeof(struct nvme_reservation_status_ext)) { >>>>>> + req->error_loc = offsetof(struct nvme_common_command, cdw10); >>>>>> + status = NVME_SC_INVALID_FIELD | NVME_SC_DNR; >>>>>> + goto out; >>>>>> + } >>>>>> + >>>>>> + data = kmalloc(num_bytes, GFP_KERNEL); >>>>>> + if (!data) { >>>>>> + status = NVME_SC_INTERNAL; >>>>>> + goto out; >>>>>> + } >>>>>> + memset(data, 0, num_bytes); >>>>>> + data->gen = cpu_to_le32(atomic_read(&pr->generation)); >>>>>> + data->ptpls = 0; >>>>>> + ctrl_eds = data->regctl_eds; >>>>>> + >>>>>> + rcu_read_lock(); >>>>>> + holder = rcu_dereference(pr->holder); >>>>>> + rtype = holder ? holder->rtype : 0; >>>>>> + data->rtype = rtype; >>>>>> + >>>>>> + list_for_each_entry_rcu(reg, &pr->registrant_list, entry) { >>>>>> + if ((void *)ctrl_eds >= (void *)(data + num_bytes)) >>>>>> + break; >>>>>> + /* >>>>>> + * Dynamic controller, set cntlid to 0xffff. >>>>>> + */ >>>>>> + ctrl_eds->cntlid = 0xffff; >>>>>> + if (rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS || >>>>>> + rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) >>>>>> + ctrl_eds->rcsts = 1; >>>>>> + if (holder && uuid_equal(®->hostid, &holder->hostid)) >>>>> is just (reg == holder) not enough here? >>>> Yes. >>>>>> + ctrl_eds->rcsts = 1; >>>>>> + uuid_copy((uuid_t *)&ctrl_eds->hostid, ®->hostid); >>>>>> + ctrl_eds->rkey = cpu_to_le64(reg->rkey); >>>>>> + ctrl_eds++; >>>>>> + num_ctrls++; >>>>>> + } >>>>>> + rcu_read_unlock(); >>>>>> + >>>>>> + put_unaligned_le16(num_ctrls, data->regctl); >>>>> Here you should report the number of all registered registrants in ns, >>>>> not the only reported. It is used by the host to understand that it got >>>>> not a full response. >>>>> NUMD field (cdw11) is about transfering the response. But the structure itsef in >>>>> the reposnse has to be complete. >>>> The NVMe spec says that: >>>> >>>> "This indicates the number of Registered Controller data structures >>>> and/or Registered Controller extended data structures contained in this >>>> data structure." >>> You read not the latest Spec again. Spec v2.1 has another statement: >>> Number of Registrants (REGSTRNT): This field indicates the number of registrants of the >>> namespace. This indicates the number of Registrant data structures or Registrant Extended data >>> structures contained in this data structure. >> Well, still, "contained in this data structure" means that we should >> report how many registrants we reported. > No, vice-versa :), that means that "this data structure" shall contain "the number > of registrants of the namespace". > >> I do a research on nvme-cli and SPDK: >> >> 1. nvme-cli: In json_nvme_resv_report, use reported regctls to traverse >> reported registrants. > I saw, and that is a security violation - to trust a data from a network. > Try to set a small NUMD and ask ReservationRepost from SPDK nvme target - > you will get a coredump of nvme-cli due to aouut-of-bound access of its > buffer (NUMD sized). > > Instead, it shall send ReservationReport twice - the first with small > buffer to get just REGSTRNT, and the second with a full buffer to get > the whole list. That is a common handling of a variable length response > in SCSI, and NVME too. My mistake, I miss that before traverse, nvme-cli cut down the regctl by request bytes(numd). >> 2. SPDK: In nvmf_ns_reservation_report, set regctl to the number of >> reported registrants. > Looks like you see again not the last version of the reference. > The latest SPDK has a correct implementation - It reports a whole > registrants list since Feb 13, 2023. > Please, follow it. > Yeah, I see, SPDK changed to all registrants number. I will change this in v13, thanks. Best Regards, Guixin Liu >> Best Regards, >> >> Guixin Liu >> >>>> It means that host use this filed to obtain the reported registrants number. >>>> >>> Think from the host point of view - how are you going to understand >>> how much registrants are there in the namespace? > BR, > Dmitry