From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756092AbcHBTSp (ORCPT ); Tue, 2 Aug 2016 15:18:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48366 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753785AbcHBTSg (ORCPT ); Tue, 2 Aug 2016 15:18:36 -0400 From: Eric Auger To: eric.auger@redhat.com, eric.auger.pro@gmail.com, christoffer.dall@linaro.org, marc.zyngier@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, will.deacon@arm.com, joro@8bytes.org, tglx@linutronix.de, jason@lakedaemon.net, linux-arm-kernel@lists.infradead.org Cc: kvm@vger.kernel.org, drjones@redhat.com, linux-kernel@vger.kernel.org, Bharat.Bhushan@freescale.com, pranav.sawargaonkar@gmail.com, p.fedin@samsung.com, iommu@lists.linux-foundation.org, Jean-Philippe.Brucker@arm.com, yehuday@marvell.com, Manish.Jaggi@caviumnetworks.com, robert.richter@caviumnetworks.com, dennis.chen@arm.com Subject: [PATCH v12 05/11] genirq/msi: msi_doorbell_calc_pages Date: Tue, 2 Aug 2016 17:23:31 +0000 Message-Id: <1470158617-7022-6-git-send-email-eric.auger@redhat.com> In-Reply-To: <1470158617-7022-1-git-send-email-eric.auger@redhat.com> References: <1470158617-7022-1-git-send-email-eric.auger@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Tue, 02 Aug 2016 17:24:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org msi_doorbell_calc_pages() sum up the number of iommu pages of a given order requested to map all the registered doorbells. This function will allow to dimension the intermediate physical address (IPA) aperture requested to map the MSI doorbells. Signed-off-by: Eric Auger --- v11 -> v12: - fix style issues: remove useless line break, remove pointless braces, fix kernel-doc comments - reword commit message - rename msi_doorbell_pages into msi_doorbell_calc_pages - rename static compute* functions v10: creation --- include/linux/msi-doorbell.h | 14 ++++++++++ kernel/irq/msi-doorbell.c | 64 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+) diff --git a/include/linux/msi-doorbell.h b/include/linux/msi-doorbell.h index a2a033b..bbedb3b 100644 --- a/include/linux/msi-doorbell.h +++ b/include/linux/msi-doorbell.h @@ -38,6 +38,15 @@ msi_doorbell_register_global(phys_addr_t base, size_t size, */ void msi_doorbell_unregister_global(struct msi_doorbell_info *db); +/** + * msi_doorbell_calc_pages - compute the number of pages + * requested to map all the registered doorbells + * @order: iommu page order + * + * Return: the number of requested pages + */ +int msi_doorbell_calc_pages(unsigned int order); + #else static inline struct msi_doorbell_info * @@ -50,6 +59,11 @@ msi_doorbell_register_global(phys_addr_t base, size_t size, static inline void msi_doorbell_unregister_global(struct msi_doorbell_info *db) {} +static inline int msi_doorbell_calc_pages(unsigned int order) +{ + return 0; +} + #endif /* CONFIG_MSI_DOORBELL */ #endif diff --git a/kernel/irq/msi-doorbell.c b/kernel/irq/msi-doorbell.c index e3e0d95..5c6c2aa 100644 --- a/kernel/irq/msi-doorbell.c +++ b/kernel/irq/msi-doorbell.c @@ -66,3 +66,67 @@ void msi_doorbell_unregister_global(struct msi_doorbell_info *dbinfo) kfree(db); } EXPORT_SYMBOL_GPL(msi_doorbell_unregister_global); + +/** + * calc_region_reqs - compute the number of pages requested to map a region + * + * @addr: physical base address of the region + * @size: size of the region + * @order: the page order + * + * Return: the number of requested pages to map this region + */ +static int calc_region_reqs(phys_addr_t addr, size_t size, unsigned int order) +{ + phys_addr_t offset, granule; + unsigned int nb_pages; + + granule = (uint64_t)(1 << order); + offset = addr & (granule - 1); + size = ALIGN(size + offset, granule); + nb_pages = size >> order; + + return nb_pages; +} + +/** + * calc_dbinfo_reqs - compute the number of pages requested to map a given + * MSI doorbell + * + * @dbi: doorbell info descriptor + * @order: page order + * + * Return: the number of requested pages to map this doorbell + */ +static int calc_dbinfo_reqs(struct msi_doorbell_info *dbi, unsigned int order) +{ + int ret = 0; + + if (!dbi->doorbell_is_percpu) { + ret = calc_region_reqs(dbi->global_doorbell, dbi->size, order); + } else { + phys_addr_t __percpu *pbase; + int cpu; + + for_each_possible_cpu(cpu) { + pbase = per_cpu_ptr(dbi->percpu_doorbells, cpu); + ret += calc_region_reqs(*pbase, dbi->size, order); + } + } + return ret; +} + +int msi_doorbell_calc_pages(unsigned int order) +{ + struct msi_doorbell *db; + int ret = 0; + + mutex_lock(&msi_doorbell_mutex); + list_for_each_entry(db, &msi_doorbell_list, next) + ret += calc_dbinfo_reqs(&db->info, order); + + mutex_unlock(&msi_doorbell_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(msi_doorbell_calc_pages); -- 1.9.1