From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751359AbdFEGPF (ORCPT ); Mon, 5 Jun 2017 02:15:05 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:54580 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751258AbdFEGPE (ORCPT ); Mon, 5 Jun 2017 02:15:04 -0400 From: Shilpasri G Bhat To: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, svaidy@linux.vnet.ibm.com, ego@linux.vnet.ibm.com, Shilpasri G Bhat Subject: [RFC 1/2] powerpc/powernv: Get a unique token for async completions Date: Mon, 5 Jun 2017 11:43:52 +0530 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1496643233-14658-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> References: <1496643233-14658-1-git-send-email-shilpa.bhat@linux.vnet.ibm.com> X-TM-AS-MML: disable x-cbid: 17060506-0008-0000-0000-00000138A19F X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17060506-0009-0000-0000-00000967C106 Message-Id: <1496643233-14658-2-git-send-email-shilpa.bhat@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-06-05_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706050116 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch adds support to get a unique token for async completion requests. This will be used for creating non-repititive request handles for consecutive requests in OPAL-OCC command/response interface. Signed-off-by: Shilpasri G Bhat --- arch/powerpc/include/asm/opal.h | 1 + arch/powerpc/platforms/powernv/opal-async.c | 46 +++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h index 588fb1c..03ed493 100644 --- a/arch/powerpc/include/asm/opal.h +++ b/arch/powerpc/include/asm/opal.h @@ -293,6 +293,7 @@ extern int opal_message_notifier_unregister(enum opal_msg_type msg_type, extern int __opal_async_get_token(void); extern int opal_async_get_token_interruptible(void); +extern int opal_async_get_unique_token_interruptible(int last_token); extern int __opal_async_release_token(int token); extern int opal_async_release_token(int token); extern int opal_async_wait_response(uint64_t token, struct opal_msg *msg); diff --git a/arch/powerpc/platforms/powernv/opal-async.c b/arch/powerpc/platforms/powernv/opal-async.c index 83bebee..8caeea2 100644 --- a/arch/powerpc/platforms/powernv/opal-async.c +++ b/arch/powerpc/platforms/powernv/opal-async.c @@ -73,6 +73,52 @@ int opal_async_get_token_interruptible(void) } EXPORT_SYMBOL_GPL(opal_async_get_token_interruptible); +static int __opal_async_get_new_token(int last_token) +{ + unsigned long flags; + int token; + + spin_lock_irqsave(&opal_async_comp_lock, flags); + token = find_next_bit(opal_async_complete_map, opal_max_async_tokens, + last_token + 1); + if (token >= opal_max_async_tokens) { + token = find_first_bit(opal_async_complete_map, + opal_max_async_tokens); + if (token >= opal_max_async_tokens || token == last_token) { + token = -EBUSY; + goto out; + } + } + + pr_debug("%s token = %d\n", __func__, token); + if (__test_and_set_bit(token, opal_async_token_map)) { + token = -EBUSY; + goto out; + } + + __clear_bit(token, opal_async_complete_map); + +out: + spin_unlock_irqrestore(&opal_async_comp_lock, flags); + return token; +} + +int opal_async_get_unique_token_interruptible(int last_token) +{ + int token; + + /* Wait until a token is available */ + if (down_interruptible(&opal_async_sem)) + return -ERESTARTSYS; + + token = __opal_async_get_new_token(last_token); + if (token < 0) + up(&opal_async_sem); + + return token; +} +EXPORT_SYMBOL_GPL(opal_async_get_unique_token_interruptible); + int __opal_async_release_token(int token) { unsigned long flags; -- 1.8.3.1