From patchwork Thu Apr 28 08:07:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Schnelle X-Patchwork-Id: 12830154 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B114C433EF for ; Thu, 28 Apr 2022 08:08:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343925AbiD1ILP (ORCPT ); Thu, 28 Apr 2022 04:11:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45554 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343811AbiD1IKs (ORCPT ); Thu, 28 Apr 2022 04:10:48 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BAE0161293; Thu, 28 Apr 2022 01:07:29 -0700 (PDT) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 23S75hR7010043; 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Thu, 28 Apr 2022 08:07:18 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 28 Apr 2022 08:07:18 +0000 (GMT) From: Niklas Schnelle To: Bjorn Helgaas , Jan Kiszka , Matthew Rosato , Pierre Morel Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH v5 1/4] PCI: Clean up pci_scan_slot() Date: Thu, 28 Apr 2022 10:07:15 +0200 Message-Id: <20220428080718.3094464-2-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220428080718.3094464-1-schnelle@linux.ibm.com> References: <20220428080718.3094464-1-schnelle@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: 99XxBhwCS6eaRDRC0J4b4-cfBs-x2QTf X-Proofpoint-ORIG-GUID: 9MBf-TQM3fLxu-72jwXtjsXKOqYtanho X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-04-27_04,2022-04-27_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 priorityscore=1501 lowpriorityscore=0 suspectscore=0 phishscore=0 impostorscore=0 mlxscore=0 spamscore=0 mlxlogscore=799 adultscore=0 malwarescore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204280049 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org While determining the next PCI function is factored out of pci_scan_slot() into next_fn() the former still handles the first function as a special case. This duplicates the code from the scan loop. Furthermore the non ARI branch of next_fn() is generally hard to understand and especially the check for multifunction devices is hidden in the handling of NULL devices for non-contiguous multifunction. It also signals that no further functions need to be scanned by returning 0 via wraparound and this is a valid function number. Improve upon this by transforming the conditions in next_fn() to be easier to understand. By changing next_fn() to return -ENODEV instead of 0 when there is no next function we can then handle the initial function inside the loop and deduplicate the shared handling. This also makes it more explicit that only function 0 must exist. No functional change is intended. Cc: Jan Kiszka Signed-off-by: Niklas Schnelle --- drivers/pci/probe.c | 38 +++++++++++++++++++------------------- 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 17a969942d37..78aa1bccab2f 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2579,8 +2579,7 @@ struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn) } EXPORT_SYMBOL(pci_scan_single_device); -static unsigned int next_fn(struct pci_bus *bus, struct pci_dev *dev, - unsigned int fn) +static int next_fn(struct pci_bus *bus, struct pci_dev *dev, int fn) { int pos; u16 cap = 0; @@ -2588,24 +2587,26 @@ static unsigned int next_fn(struct pci_bus *bus, struct pci_dev *dev, if (pci_ari_enabled(bus)) { if (!dev) - return 0; + return -ENODEV; pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI); if (!pos) - return 0; + return -ENODEV; pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap); next_fn = PCI_ARI_CAP_NFN(cap); if (next_fn <= fn) - return 0; /* protect against malformed list */ + return -ENODEV; /* protect against malformed list */ return next_fn; } + if (fn >= 7) + return -ENODEV; - /* dev may be NULL for non-contiguous multifunction devices */ - if (!dev || dev->multifunction) - return (fn + 1) % 8; + /* only multifunction devices may have more functions */ + if (dev && !dev->multifunction) + return -ENODEV; - return 0; + return fn + 1; } static int only_one_child(struct pci_bus *bus) @@ -2643,26 +2644,25 @@ static int only_one_child(struct pci_bus *bus) */ int pci_scan_slot(struct pci_bus *bus, int devfn) { - unsigned int fn, nr = 0; struct pci_dev *dev; + int fn = 0, nr = 0; if (only_one_child(bus) && (devfn > 0)) return 0; /* Already scanned the entire slot */ - dev = pci_scan_single_device(bus, devfn); - if (!dev) - return 0; - if (!pci_dev_is_added(dev)) - nr++; - - for (fn = next_fn(bus, dev, 0); fn > 0; fn = next_fn(bus, dev, fn)) { + do { dev = pci_scan_single_device(bus, devfn + fn); if (dev) { if (!pci_dev_is_added(dev)) nr++; - dev->multifunction = 1; + if (fn > 0) + dev->multifunction = 1; + } else if (fn == 0) { + /* function 0 is required */ + break; } - } + fn = next_fn(bus, dev, fn); + } while (fn >= 0); /* Only one slot has PCIe device */ if (bus->self && nr) From patchwork Thu Apr 28 08:07:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Schnelle X-Patchwork-Id: 12830156 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F0F55C433EF for ; Thu, 28 Apr 2022 08:08:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343936AbiD1ILT (ORCPT ); Thu, 28 Apr 2022 04:11:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343833AbiD1IKs (ORCPT ); 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Thu, 28 Apr 2022 08:07:19 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6EB4C4C040; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2E2054C044; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) From: Niklas Schnelle To: Bjorn Helgaas , Jan Kiszka , Matthew Rosato , Pierre Morel Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH v5 2/4] PCI: Move jailhouse's isolated function handling to pci_scan_slot() Date: Thu, 28 Apr 2022 10:07:16 +0200 Message-Id: <20220428080718.3094464-3-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220428080718.3094464-1-schnelle@linux.ibm.com> References: <20220428080718.3094464-1-schnelle@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-GUID: h3vu6NpiKc1Lkc7QlOOnoNIOtdGxAevY X-Proofpoint-ORIG-GUID: NWJDT8M5a_TtT6KVhxO0PWnDXrjZIFJg X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-04-27_04,2022-04-27_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 malwarescore=0 mlxscore=0 adultscore=0 mlxlogscore=999 priorityscore=1501 bulkscore=0 clxscore=1015 lowpriorityscore=0 spamscore=0 suspectscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204280049 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The special case of the jailhouse hypervisor passing through individual PCI functions handles scanning for PCI functions even if function 0 does not exist. Currently this is done with an extra loop duplicating the one in pci_scan_slot(). By incorporating the check for jailhouse_paravirt() into pci_scan_slot() we can instead do this as part of the normal slot scan. Note that with the assignment of dev->multifunction gated by fn > 0 we set dev->multifunction unconditionally for all functions if function 0 is missing just as in the existing jailhouse loop. The only functional change is that we now call pcie_aspm_init_link_state() for these functions but this already happened if function 0 was passed through and should not be a problem. Cc: Jan Kiszka Link: https://lore.kernel.org/linux-pci/20220408224514.GA353445@bhelgaas/ Suggested-by: Bjorn Helgaas Signed-off-by: Niklas Schnelle --- drivers/pci/probe.c | 30 ++++++++++-------------------- 1 file changed, 10 insertions(+), 20 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 78aa1bccab2f..3029edc68ff7 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2658,8 +2658,13 @@ int pci_scan_slot(struct pci_bus *bus, int devfn) if (fn > 0) dev->multifunction = 1; } else if (fn == 0) { - /* function 0 is required */ - break; + /* + * function 0 is required unless we are running on + * a hypervisor which passes through individual PCI + * functions. + */ + if (!jailhouse_paravirt()) + break; } fn = next_fn(bus, dev, fn); } while (fn >= 0); @@ -2858,29 +2863,14 @@ static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus, { unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0; unsigned int start = bus->busn_res.start; - unsigned int devfn, fn, cmax, max = start; + unsigned int devfn, cmax, max = start; struct pci_dev *dev; - int nr_devs; dev_dbg(&bus->dev, "scanning bus\n"); /* Go find them, Rover! */ - for (devfn = 0; devfn < 256; devfn += 8) { - nr_devs = pci_scan_slot(bus, devfn); - - /* - * The Jailhouse hypervisor may pass individual functions of a - * multi-function device to a guest without passing function 0. - * Look for them as well. - */ - if (jailhouse_paravirt() && nr_devs == 0) { - for (fn = 1; fn < 8; fn++) { - dev = pci_scan_single_device(bus, devfn + fn); - if (dev) - dev->multifunction = 1; - } - } - } + for (devfn = 0; devfn < 256; devfn += 8) + pci_scan_slot(bus, devfn); /* Reserve buses for SR-IOV capability */ used_buses = pci_iov_bus_range(bus); From patchwork Thu Apr 28 08:07:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Schnelle X-Patchwork-Id: 12830155 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56163C43219 for ; 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Thu, 28 Apr 2022 08:07:19 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BAF514C04A; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 79AF54C046; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) From: Niklas Schnelle To: Bjorn Helgaas , Jan Kiszka , Matthew Rosato , Pierre Morel Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH v5 3/4] PCI: Extend isolated function probing to s390 Date: Thu, 28 Apr 2022 10:07:17 +0200 Message-Id: <20220428080718.3094464-4-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220428080718.3094464-1-schnelle@linux.ibm.com> References: <20220428080718.3094464-1-schnelle@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: hF0KEBPr7YeZ1OczsSRlpTs9XSHTCEFo X-Proofpoint-ORIG-GUID: 08pUsJU316UAjGNJ5zfbsDQg0wrIyl5U X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-04-27_04,2022-04-27_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 impostorscore=0 lowpriorityscore=0 suspectscore=0 clxscore=1015 phishscore=0 mlxlogscore=719 spamscore=0 adultscore=0 priorityscore=1501 mlxscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204280049 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Like the jailhouse hypervisor s390's PCI architecture allows passing isolated PCI functions to an OS instance. As of now this is was not utilized even with multi-function support as the s390 PCI code makes sure that only virtual PCI busses including a function with devfn 0 are presented to the PCI subsystem. A subsequent change will remove this restriction. Allow probing such functions by replacing the existing check for jailhouse_paravirt() with a new hypervisor_isolated_pci_functions() helper. Cc: Jan Kiszka Signed-off-by: Niklas Schnelle --- drivers/pci/probe.c | 2 +- include/linux/hypervisor.h | 8 ++++++++ 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 3029edc68ff7..4e27cc929095 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2663,7 +2663,7 @@ int pci_scan_slot(struct pci_bus *bus, int devfn) * a hypervisor which passes through individual PCI * functions. */ - if (!jailhouse_paravirt()) + if (!hypervisor_isolated_pci_functions()) break; } fn = next_fn(bus, dev, fn); diff --git a/include/linux/hypervisor.h b/include/linux/hypervisor.h index fc08b433c856..33b1c0482aac 100644 --- a/include/linux/hypervisor.h +++ b/include/linux/hypervisor.h @@ -32,4 +32,12 @@ static inline bool jailhouse_paravirt(void) #endif /* !CONFIG_X86 */ +static inline bool hypervisor_isolated_pci_functions(void) +{ + if (IS_ENABLED(CONFIG_S390)) + return true; + else + return jailhouse_paravirt(); +} + #endif /* __LINUX_HYPEVISOR_H */ From patchwork Thu Apr 28 08:07:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Niklas Schnelle X-Patchwork-Id: 12830153 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9CDF7C433EF for ; Thu, 28 Apr 2022 08:07:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343900AbiD1ILJ (ORCPT ); Thu, 28 Apr 2022 04:11:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46408 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343806AbiD1IKr (ORCPT ); Thu, 28 Apr 2022 04:10:47 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40CF760DBB; Thu, 28 Apr 2022 01:07:29 -0700 (PDT) Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 23S6LgZF030310; 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Thu, 28 Apr 2022 08:07:19 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 28 Apr 2022 08:07:19 +0000 (GMT) From: Niklas Schnelle To: Bjorn Helgaas , Jan Kiszka , Matthew Rosato , Pierre Morel Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-s390@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH v5 4/4] s390/pci: allow zPCI zbus without a function zero Date: Thu, 28 Apr 2022 10:07:18 +0200 Message-Id: <20220428080718.3094464-5-schnelle@linux.ibm.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220428080718.3094464-1-schnelle@linux.ibm.com> References: <20220428080718.3094464-1-schnelle@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: YREMAafcIwl6h5SIEzPTng5qmUPkAUXW X-Proofpoint-GUID: GNgl7z6oExOfieG7qfji9zBr45z0JBTl X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.486,FMLib:17.11.64.514 definitions=2022-04-27_04,2022-04-27_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=931 bulkscore=0 malwarescore=0 suspectscore=0 impostorscore=0 clxscore=1015 adultscore=0 priorityscore=1501 spamscore=0 lowpriorityscore=0 phishscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204280049 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Currently the zPCI code block PCI bus creation and probing of a zPCI zbus unless there is a PCI function with devfn 0. This is always the case for the PCI functions with hidden RID but may keep PCI functions from a multi-function PCI device with RID information invisible until the function 0 becomes visible. Worse as a PCI bus is necessary to even present a PCI hotplug slot even that remains invisible. With the probing of these so called isolated PCI functions enabled for s390 in common code this restriction is no longer necessary. On network cards with multiple ports and a PF per port this also allows using each port on its own while still providing the physical PCI topology information in the devfn needed to associate VFs with their parent PF. Signed-off-by: Niklas Schnelle --- arch/s390/pci/pci_bus.c | 82 ++++++++++------------------------------- 1 file changed, 20 insertions(+), 62 deletions(-) diff --git a/arch/s390/pci/pci_bus.c b/arch/s390/pci/pci_bus.c index 5d77acbd1c87..6a8da1b742ae 100644 --- a/arch/s390/pci/pci_bus.c +++ b/arch/s390/pci/pci_bus.c @@ -145,9 +145,6 @@ int zpci_bus_scan_bus(struct zpci_bus *zbus) struct zpci_dev *zdev; int devfn, rc, ret = 0; - if (!zbus->function[0]) - return 0; - for (devfn = 0; devfn < ZPCI_FUNCTIONS_PER_BUS; devfn++) { zdev = zbus->function[devfn]; if (zdev && zdev->state == ZPCI_FN_STATE_CONFIGURED) { @@ -184,26 +181,26 @@ void zpci_bus_scan_busses(void) /* zpci_bus_create_pci_bus - Create the PCI bus associated with this zbus * @zbus: the zbus holding the zdevices - * @f0: function 0 of the bus + * @fr: PCI root function that will determine the bus's domain, and bus speeed * @ops: the pci operations * - * Function zero is taken as a parameter as this is used to determine the - * domain, multifunction property and maximum bus speed of the entire bus. + * The PCI function @fr determines the domain (its UID), multifunction property + * and maximum bus speed of the entire bus. * * Return: 0 on success, an error code otherwise */ -static int zpci_bus_create_pci_bus(struct zpci_bus *zbus, struct zpci_dev *f0, struct pci_ops *ops) +static int zpci_bus_create_pci_bus(struct zpci_bus *zbus, struct zpci_dev *fr, struct pci_ops *ops) { struct pci_bus *bus; int domain; - domain = zpci_alloc_domain((u16)f0->uid); + domain = zpci_alloc_domain((u16)fr->uid); if (domain < 0) return domain; zbus->domain_nr = domain; - zbus->multifunction = f0->rid_available; - zbus->max_bus_speed = f0->max_bus_speed; + zbus->multifunction = fr->rid_available; + zbus->max_bus_speed = fr->max_bus_speed; /* * Note that the zbus->resources are taken over and zbus->resources @@ -303,47 +300,6 @@ void pcibios_bus_add_device(struct pci_dev *pdev) } } -/* zpci_bus_create_hotplug_slots - Add hotplug slot(s) for device added to bus - * @zdev: the zPCI device that was newly added - * - * Add the hotplug slot(s) for the newly added PCI function. Normally this is - * simply the slot for the function itself. If however we are adding the - * function 0 on a zbus, it might be that we already registered functions on - * that zbus but could not create their hotplug slots yet so add those now too. - * - * Return: 0 on success, an error code otherwise - */ -static int zpci_bus_create_hotplug_slots(struct zpci_dev *zdev) -{ - struct zpci_bus *zbus = zdev->zbus; - int devfn, rc = 0; - - rc = zpci_init_slot(zdev); - if (rc) - return rc; - zdev->has_hp_slot = 1; - - if (zdev->devfn == 0 && zbus->multifunction) { - /* Now that function 0 is there we can finally create the - * hotplug slots for those functions with devfn != 0 that have - * been parked in zbus->function[] waiting for us to be able to - * create the PCI bus. - */ - for (devfn = 1; devfn < ZPCI_FUNCTIONS_PER_BUS; devfn++) { - zdev = zbus->function[devfn]; - if (zdev && !zdev->has_hp_slot) { - rc = zpci_init_slot(zdev); - if (rc) - return rc; - zdev->has_hp_slot = 1; - } - } - - } - - return rc; -} - static int zpci_bus_add_device(struct zpci_bus *zbus, struct zpci_dev *zdev) { int rc = -EINVAL; @@ -352,21 +308,19 @@ static int zpci_bus_add_device(struct zpci_bus *zbus, struct zpci_dev *zdev) pr_err("devfn %04x is already assigned\n", zdev->devfn); return rc; } + zdev->zbus = zbus; zbus->function[zdev->devfn] = zdev; zpci_nb_devices++; - if (zbus->bus) { - if (zbus->multifunction && !zdev->rid_available) { - WARN_ONCE(1, "rid_available not set for multifunction\n"); - goto error; - } - - zpci_bus_create_hotplug_slots(zdev); - } else { - /* Hotplug slot will be created once function 0 appears */ - zbus->multifunction = 1; + if (zbus->multifunction && !zdev->rid_available) { + WARN_ONCE(1, "rid_available not set for multifunction\n"); + goto error; } + rc = zpci_init_slot(zdev); + if (rc) + goto error; + zdev->has_hp_slot = 1; return 0; @@ -400,7 +354,11 @@ int zpci_bus_device_register(struct zpci_dev *zdev, struct pci_ops *ops) return -ENOMEM; } - if (zdev->devfn == 0) { + if (!zbus->bus) { + /* The UID of the first PCI function registered with a zpci_bus + * is used as the domain number for that bus. Currently there + * is exactly one zpci_bus per domain. + */ rc = zpci_bus_create_pci_bus(zbus, zdev, ops); if (rc) goto error;