From patchwork Fri Jun 15 18:23:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhu Lingshan X-Patchwork-Id: 10467347 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 6BAC2601C2 for ; Fri, 15 Jun 2018 18:25:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5D63A28E3B for ; Fri, 15 Jun 2018 18:25:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5224728E41; Fri, 15 Jun 2018 18:25:50 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EE5F228E3B for ; Fri, 15 Jun 2018 18:25:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756399AbeFOSZq (ORCPT ); Fri, 15 Jun 2018 14:25:46 -0400 Received: from smtp2.provo.novell.com ([137.65.250.81]:49258 "EHLO smtp2.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756347AbeFOSZp (ORCPT ); Fri, 15 Jun 2018 14:25:45 -0400 Received: from vstart.localdomain (prv-ext-foundry1int.gns.novell.com [137.65.251.240]) by smtp2.provo.novell.com with ESMTP (TLS encrypted); Fri, 15 Jun 2018 12:25:36 -0600 From: Zhu Lingshan To: target-devel@vger.kernel.org, linux-scsi@vger.kernel.org, nab@linux-iscsi.org, mchristi@redhat.com, martin.petersen@oracle.com Cc: hare@suse.de, lduncan@suse.com, ddiss@suse.de, lszhu@suse.de, Zhu Lingshan Subject: [PATCH 32/33] TCMU PR: implementation of PR clear for TCMU Date: Sat, 16 Jun 2018 02:23:41 +0800 Message-Id: <20180615182342.6239-32-lszhu@suse.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180615182342.6239-1-lszhu@suse.com> References: <20180615182342.6239-1-lszhu@suse.com> Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch added a function tcmu_execute_pr_clear() which can help perform Persistent Reservation clear operation, this means clear reservations and registrations. Signed-off-by: Zhu Lingshan --- drivers/target/target_core_user.c | 108 ++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 532401a9f433..c8d0ea330984 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -3251,6 +3251,114 @@ tcmu_execute_pr_release(struct se_cmd *cmd, int type, u64 key) } +static sense_reason_t +tcmu_execute_pr_clear(struct se_cmd *cmd, u64 key) +{ + struct se_device *dev = cmd->se_dev; + struct tcmu_dev *udev = TCMU_DEV(dev); + char nexus_buf[TCMU_PR_IT_NEXUS_MAXLEN]; + struct tcmu_pr_info *pr_info; + struct tcmu_pr_reg *reg; + struct tcmu_pr_reg *existing_reg; + char *pr_xattr; + int pr_xattr_len; + int rc; + sense_reason_t ret; + int retries = 0; + + if (!cmd->se_sess || !cmd->se_lun) { + pr_err("SPC-3 PR: se_sess || struct se_lun is NULL!\n"); + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + } + + rc = tcmu_gen_it_nexus(cmd->se_sess, nexus_buf, + ARRAY_SIZE(nexus_buf)); + if (rc < 0) + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + + mutex_lock(&udev->pr_info.pr_info_lock); + udev->pr_info.pr_info_buf = kzalloc(TCMU_PR_INFO_XATTR_MAX_SIZE, + GFP_KERNEL); + +retry: + pr_info = NULL; + pr_xattr = NULL; + pr_xattr_len = 0; + rc = tcmu_pr_info_get(udev, &pr_info, &pr_xattr, + &pr_xattr_len); + if (rc < 0) { + /* existing registration required for clear */ + pr_err("failed to obtain PR info\n"); + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto err_info_free; + } + + /* check for an existing registration */ + existing_reg = NULL; + list_for_each_entry(reg, &pr_info->regs, regs_node) { + if (!strncmp(reg->it_nexus, nexus_buf, + ARRAY_SIZE(nexus_buf))) { + pr_debug("found existing PR reg for %s\n", nexus_buf); + existing_reg = reg; + break; + } + } + + if (!existing_reg) { + pr_err("SPC-3 PR: Unable to locate registration for CLEAR\n"); + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto err_info_free; + } + + if (key != existing_reg->key) { + pr_err("SPC-3 PR CLEAR: Received res_key: 0x%016llx ", key); + pr_err("does not match existing SA res_key: 0x%016llx\n", + existing_reg->key); + ret = TCM_RESERVATION_CONFLICT; + goto err_info_free; + } + + /* release the persistent reservation, if any */ + if (pr_info->rsv) + tcmu_pr_info_rsv_clear(pr_info); + + /* remove all registrations */ + list_for_each_entry_safe(existing_reg, reg, &pr_info->regs, regs_node) { + tcmu_pr_info_clear_reg(pr_info, existing_reg); + } + + /* PR generation must be incremented on successful CLEAR */ + pr_info->gen++; + + rc = tcmu_pr_info_replace(udev, pr_xattr, pr_xattr_len, + pr_info); + if (rc == -ECANCELED) { + pr_warn("Atomic PR info update failed due to parallel "); + pr_warn("change, expected(%d) %s. Retrying...\n", + pr_xattr_len, pr_xattr); + retries++; + if (retries <= TCMU_PR_REG_MAX_RETRIES) { + tcmu_pr_info_free(pr_info); + kfree(pr_xattr); + goto retry; + } + } + if (rc < 0) { + pr_err("atomic PR info update failed: %d\n", rc); + ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; + goto err_info_free; + } + + ret = TCM_NO_SENSE; +err_info_free: + tcmu_pr_info_free(pr_info); + kfree(pr_xattr); + kfree(udev->pr_info.pr_info_buf); + mutex_unlock(&udev->pr_info.pr_info_lock); + return ret; +} + + static int tcmu_configure_device(struct se_device *dev) { struct tcmu_dev *udev = TCMU_DEV(dev);