From patchwork Fri Aug 21 00:24:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11727395 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 82E6F138C for ; Fri, 21 Aug 2020 02:26:54 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 5F27720732 for ; Fri, 21 Aug 2020 02:26:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="u83GoZD7"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="uYI8PYXm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5F27720732 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k8wlF-0004wY-DL; Fri, 21 Aug 2020 02:26:33 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k8wcz-0002BQ-VT for xen-devel@lists.xenproject.org; Fri, 21 Aug 2020 02:18:01 +0000 X-Inumbo-ID: 7975cab2-7ca2-48a7-afd2-ccd74e7ec5da Received: from galois.linutronix.de (unknown [193.142.43.55]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 7975cab2-7ca2-48a7-afd2-ccd74e7ec5da; Fri, 21 Aug 2020 02:17:10 +0000 (UTC) Message-Id: <20200821002947.775455439@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1597976229; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=5rm8mQE6Z9mzP1/Hjhj/ozCQldgRwMSJG8h+qhJlUXA=; b=u83GoZD7MYm1uxfJ39lk5U5vQF2a+dUEFcGURH/CfalKLcghkdDrT1n2jjBPck0+r2r1I1 DlGtNwEHaNgPTtqkrCx1GlqSrmUcZSeeP6A3ZpdUX+DF+VxxpHrHIqJCPm/1k7z5AvZmSr +CelVad8Y/oRsxD+lP0cgDORIAsgRCYAG52SkufeR5G4K4lop9+ReQpKwlposJ+pXXS6t2 GUGBkn8g9w2yjmj7G6ZjLgL8A67sysaVJbmknShDj43aTG6ukY4oATY42lmry9TvhkJqmx zqps7udq3hQ53fB/cTXpOgS1wmOL33SDUr+ameR3IGL+83fHLLPHHpuaSNVxJA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1597976229; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=5rm8mQE6Z9mzP1/Hjhj/ozCQldgRwMSJG8h+qhJlUXA=; b=uYI8PYXm9tBwGXdQfjD44Lqs0sQhcrFf16gEzewh5ZbvPbY0jEqTtygLqwx2S0Ur6ouQqD XhZKak8nvK3ezlDw== Date: Fri, 21 Aug 2020 02:24:49 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Marc Zyngier , Joerg Roedel , iommu@lists.linux-foundation.org, linux-hyperv@vger.kernel.org, Haiyang Zhang , Jon Derrick , Lu Baolu , Wei Liu , "K. Y. Srinivasan" , Stephen Hemminger , Steve Wahl , Dimitri Sivanich , Russ Anderson , linux-pci@vger.kernel.org, Bjorn Helgaas , Lorenzo Pieralisi , Jonathan Derrick , Konrad Rzeszutek Wilk , xen-devel@lists.xenproject.org, Juergen Gross , Boris Ostrovsky , Stefano Stabellini , Greg Kroah-Hartman , "Rafael J. Wysocki" , Megha Dey , Jason Gunthorpe , Dave Jiang , Alex Williamson , Jacob Pan , Baolu Lu , Kevin Tian , Dan Williams Subject: [patch RFC 25/38] irqdomain/msi: Allow to override msi_domain_alloc/free_irqs() References: <20200821002424.119492231@linutronix.de> MIME-Version: 1.0 Content-Disposition: inline; filename*0*=utf-8''irqdomain-msi--Allow-to-override-msi_domain_alloc-free_ir; filename*1*=qs--.patch Content-transfer-encoding: 8-bit X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" To support MSI irq domains which do not fit at all into the regular MSI irqdomain scheme, like the XEN MSI interrupt management for PV/HVM/DOM0, it's necessary to allow to override the alloc/free implementation. This is a preperatory step to switch X86 away from arch_*_msi_irqs() and store the irq domain pointer right in struct device. No functional change for existing MSI irq domain users. Aside of the evil XEN wrapper this is also useful for special MSI domains which need to do extra alloc/free work before/after calling the generic core function. Work like allocating/freeing MSI descriptors, MSI storage space etc. Signed-off-by: Thomas Gleixner Cc: Marc Zyngier --- include/linux/msi.h | 27 ++++++++++++++++++++ kernel/irq/msi.c | 70 +++++++++++++++++++++++++++++++++++----------------- 2 files changed, 75 insertions(+), 22 deletions(-) --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -241,6 +241,10 @@ struct msi_domain_info; * @msi_finish: Optional callback to finalize the allocation * @set_desc: Set the msi descriptor for an interrupt * @handle_error: Optional error handler if the allocation fails + * @domain_alloc_irqs: Optional function to override the default allocation + * function. + * @domain_free_irqs: Optional function to override the default free + * function. * * @get_hwirq, @msi_init and @msi_free are callbacks used by * msi_create_irq_domain() and related interfaces @@ -248,6 +252,22 @@ struct msi_domain_info; * @msi_check, @msi_prepare, @msi_finish, @set_desc and @handle_error * are callbacks used by msi_domain_alloc_irqs() and related * interfaces which are based on msi_desc. + * + * @domain_alloc_irqs, @domain_free_irqs can be used to override the + * default allocation/free functions (__msi_domain_alloc/free_irqs). This + * is initially for a wrapper around XENs seperate MSI universe which can't + * be wrapped into the regular irq domains concepts by mere mortals. This + * allows to universally use msi_domain_alloc/free_irqs without having to + * special case XEN all over the place. + * + * Contrary to other operations @domain_alloc_irqs and @domain_free_irqs + * are set to the default implementation if NULL and even when + * MSI_FLAG_USE_DEF_DOM_OPS is not set to avoid breaking existing users and + * because these callbacks are obviously mandatory. + * + * This is NOT meant to be abused, but it can be useful to build wrappers + * for specialized MSI irq domains which need extra work before and after + * calling __msi_domain_alloc_irqs()/__msi_domain_free_irqs(). */ struct msi_domain_ops { irq_hw_number_t (*get_hwirq)(struct msi_domain_info *info, @@ -270,6 +290,10 @@ struct msi_domain_ops { struct msi_desc *desc); int (*handle_error)(struct irq_domain *domain, struct msi_desc *desc, int error); + int (*domain_alloc_irqs)(struct irq_domain *domain, + struct device *dev, int nvec); + void (*domain_free_irqs)(struct irq_domain *domain, + struct device *dev); }; /** @@ -327,8 +351,11 @@ int msi_domain_set_affinity(struct irq_d struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, struct msi_domain_info *info, struct irq_domain *parent); +int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, + int nvec); int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec); +void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev); void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev); struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain); --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -229,11 +229,13 @@ static int msi_domain_ops_check(struct i } static struct msi_domain_ops msi_domain_ops_default = { - .get_hwirq = msi_domain_ops_get_hwirq, - .msi_init = msi_domain_ops_init, - .msi_check = msi_domain_ops_check, - .msi_prepare = msi_domain_ops_prepare, - .set_desc = msi_domain_ops_set_desc, + .get_hwirq = msi_domain_ops_get_hwirq, + .msi_init = msi_domain_ops_init, + .msi_check = msi_domain_ops_check, + .msi_prepare = msi_domain_ops_prepare, + .set_desc = msi_domain_ops_set_desc, + .domain_alloc_irqs = __msi_domain_alloc_irqs, + .domain_free_irqs = __msi_domain_free_irqs, }; static void msi_domain_update_dom_ops(struct msi_domain_info *info) @@ -245,6 +247,14 @@ static void msi_domain_update_dom_ops(st return; } + if (ops->domain_alloc_irqs == NULL) + ops->domain_alloc_irqs = msi_domain_ops_default.domain_alloc_irqs; + if (ops->domain_free_irqs == NULL) + ops->domain_free_irqs = msi_domain_ops_default.domain_free_irqs; + + if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS)) + return; + if (ops->get_hwirq == NULL) ops->get_hwirq = msi_domain_ops_default.get_hwirq; if (ops->msi_init == NULL) @@ -278,8 +288,7 @@ struct irq_domain *msi_create_irq_domain { struct irq_domain *domain; - if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) - msi_domain_update_dom_ops(info); + msi_domain_update_dom_ops(info); if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) msi_domain_update_chip_ops(info); @@ -386,17 +395,8 @@ static bool msi_check_reservation_mode(s return desc->msi_attrib.is_msix || desc->msi_attrib.maskbit; } -/** - * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain - * @domain: The domain to allocate from - * @dev: Pointer to device struct of the device for which the interrupts - * are allocated - * @nvec: The number of interrupts to allocate - * - * Returns 0 on success or an error code. - */ -int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, - int nvec) +int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, + int nvec) { struct msi_domain_info *info = domain->host_data; struct msi_domain_ops *ops = info->ops; @@ -490,12 +490,24 @@ int msi_domain_alloc_irqs(struct irq_dom } /** - * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev - * @domain: The domain to managing the interrupts + * msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain + * @domain: The domain to allocate from * @dev: Pointer to device struct of the device for which the interrupts - * are free + * are allocated + * @nvec: The number of interrupts to allocate + * + * Returns 0 on success or an error code. */ -void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) +int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, + int nvec) +{ + struct msi_domain_info *info = domain->host_data; + struct msi_domain_ops *ops = info->ops; + + return ops->domain_alloc_irqs(domain, dev, nvec); +} + +void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) { struct msi_desc *desc; @@ -513,6 +525,20 @@ void msi_domain_free_irqs(struct irq_dom } /** + * __msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @dev + * @domain: The domain to managing the interrupts + * @dev: Pointer to device struct of the device for which the interrupts + * are free + */ +void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) +{ + struct msi_domain_info *info = domain->host_data; + struct msi_domain_ops *ops = info->ops; + + return ops->domain_free_irqs(domain, dev); +} + +/** * msi_get_domain_info - Get the MSI interrupt domain info for @domain * @domain: The interrupt domain to retrieve data from *