From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre Morel Subject: [PATCH v1] iommu/s390: Declare s390 iommu reserved regions Date: Tue, 15 Jan 2019 18:37:30 +0100 Message-ID: <1547573850-9459-2-git-send-email-pmorel@linux.ibm.com> References: <1547573850-9459-1-git-send-email-pmorel@linux.ibm.com> Return-path: In-Reply-To: <1547573850-9459-1-git-send-email-pmorel@linux.ibm.com> Sender: linux-kernel-owner@vger.kernel.org To: gerald.schaefer@de.ibm.com Cc: joro@8bytes.org, linux-s390@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, alex.williamson@redhat.com, shameerali.kolothum.thodi@huawei.com, walling@linux.ibm.com List-Id: iommu@lists.linux-foundation.org The s390 iommu can only allow DMA transactions between the zPCI device entries start_dma and end_dma. Let's declare the regions before start_dma and after end_dma as reserved regions using the appropriate callback in iommu_ops. Signed-off-by: Pierre Morel --- drivers/iommu/s390-iommu.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c index 22d4db3..5ca91a1 100644 --- a/drivers/iommu/s390-iommu.c +++ b/drivers/iommu/s390-iommu.c @@ -363,6 +363,33 @@ void zpci_destroy_iommu(struct zpci_dev *zdev) iommu_device_sysfs_remove(&zdev->iommu_dev); } +static void s390_get_resv_regions(struct device *dev, struct list_head *head) +{ + struct iommu_resv_region *region; + struct zpci_dev *zdev = to_pci_dev(dev)->sysdata; + + region = iommu_alloc_resv_region(0, zdev->start_dma, + 0, IOMMU_RESV_RESERVED); + if (!region) + return; + list_add_tail(®ion->list, head); + + region = iommu_alloc_resv_region(zdev->end_dma + 1, + ~0UL - zdev->end_dma, + 0, IOMMU_RESV_RESERVED); + if (!region) + return; + list_add_tail(®ion->list, head); +} + +static void s390_put_resv_regions(struct device *dev, struct list_head *head) +{ + struct iommu_resv_region *entry, *next; + + list_for_each_entry_safe(entry, next, head, list) + kfree(entry); +} + static const struct iommu_ops s390_iommu_ops = { .capable = s390_iommu_capable, .domain_alloc = s390_domain_alloc, @@ -376,6 +403,8 @@ static const struct iommu_ops s390_iommu_ops = { .remove_device = s390_iommu_remove_device, .device_group = generic_device_group, .pgsize_bitmap = S390_IOMMU_PGSIZES, + .get_resv_regions = s390_get_resv_regions, + .put_resv_regions = s390_put_resv_regions, }; static int __init s390_iommu_init(void) -- 2.7.4