From: Matthew Rosato Date: Fri, 11 Apr 2025 20:24:33 +0000 (-0400) Subject: iommu/s390: allow larger region tables X-Git-Tag: v6.16-rc1~110^2^9 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=81244074b518aeb90de5f68e7e825564c29c5c50;p=thirdparty%2Fkernel%2Flinux.git iommu/s390: allow larger region tables Extend the aperture calculation to consider sizes beyond the maximum size of a region third table. Attempt to always use the smallest table size possible to avoid unnecessary extra steps during translation. Update reserved region calculations to use the appropriate table size. Signed-off-by: Matthew Rosato Reviewed-by: Niklas Schnelle Tested-by: Niklas Schnelle Link: https://lore.kernel.org/r/20250411202433.181683-6-mjrosato@linux.ibm.com Signed-off-by: Joerg Roedel --- diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h index 8d8962e4fd58f..d12e172016619 100644 --- a/arch/s390/include/asm/pci_dma.h +++ b/arch/s390/include/asm/pci_dma.h @@ -25,6 +25,7 @@ enum zpci_ioat_dtype { #define ZPCI_KEY (PAGE_DEFAULT_KEY << 5) #define ZPCI_TABLE_SIZE_RT (1UL << 42) +#define ZPCI_TABLE_SIZE_RS (1UL << 53) #define ZPCI_IOTA_STO_FLAG (ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_ST) #define ZPCI_IOTA_RTTO_FLAG (ZPCI_IOTA_IOT_ENABLED | ZPCI_KEY | ZPCI_IOTA_DT_RT) diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c index 46f45b1369937..433b59f435302 100644 --- a/drivers/iommu/s390-iommu.c +++ b/drivers/iommu/s390-iommu.c @@ -511,9 +511,25 @@ static bool s390_iommu_capable(struct device *dev, enum iommu_cap cap) } } +static inline u64 max_tbl_size(struct s390_domain *domain) +{ + switch (domain->origin_type) { + case ZPCI_TABLE_TYPE_RTX: + return ZPCI_TABLE_SIZE_RT - 1; + case ZPCI_TABLE_TYPE_RSX: + return ZPCI_TABLE_SIZE_RS - 1; + case ZPCI_TABLE_TYPE_RFX: + return U64_MAX; + default: + return 0; + } +} + static struct iommu_domain *s390_domain_alloc_paging(struct device *dev) { + struct zpci_dev *zdev = to_zpci_dev(dev); struct s390_domain *s390_domain; + u64 aperture_size; s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL); if (!s390_domain) @@ -524,10 +540,26 @@ static struct iommu_domain *s390_domain_alloc_paging(struct device *dev) kfree(s390_domain); return NULL; } + + aperture_size = min(s390_iommu_aperture, + zdev->end_dma - zdev->start_dma + 1); + if (aperture_size <= (ZPCI_TABLE_SIZE_RT - zdev->start_dma)) { + s390_domain->origin_type = ZPCI_TABLE_TYPE_RTX; + } else if (aperture_size <= (ZPCI_TABLE_SIZE_RS - zdev->start_dma) && + (zdev->dtsm & ZPCI_IOTA_DT_RS)) { + s390_domain->origin_type = ZPCI_TABLE_TYPE_RSX; + } else if (zdev->dtsm & ZPCI_IOTA_DT_RF) { + s390_domain->origin_type = ZPCI_TABLE_TYPE_RFX; + } else { + /* Assume RTX available */ + s390_domain->origin_type = ZPCI_TABLE_TYPE_RTX; + aperture_size = ZPCI_TABLE_SIZE_RT - zdev->start_dma; + } + zdev->end_dma = zdev->start_dma + aperture_size - 1; + s390_domain->domain.geometry.force_aperture = true; s390_domain->domain.geometry.aperture_start = 0; - s390_domain->domain.geometry.aperture_end = ZPCI_TABLE_SIZE_RT - 1; - s390_domain->origin_type = ZPCI_TABLE_TYPE_RTX; + s390_domain->domain.geometry.aperture_end = max_tbl_size(s390_domain); spin_lock_init(&s390_domain->list_lock); INIT_LIST_HEAD_RCU(&s390_domain->devices); @@ -680,6 +712,8 @@ static void s390_iommu_get_resv_regions(struct device *dev, { struct zpci_dev *zdev = to_zpci_dev(dev); struct iommu_resv_region *region; + u64 max_size, end_resv; + unsigned long flags; if (zdev->start_dma) { region = iommu_alloc_resv_region(0, zdev->start_dma, 0, @@ -689,10 +723,21 @@ static void s390_iommu_get_resv_regions(struct device *dev, list_add_tail(®ion->list, list); } - if (zdev->end_dma < ZPCI_TABLE_SIZE_RT - 1) { - region = iommu_alloc_resv_region(zdev->end_dma + 1, - ZPCI_TABLE_SIZE_RT - zdev->end_dma - 1, - 0, IOMMU_RESV_RESERVED, GFP_KERNEL); + spin_lock_irqsave(&zdev->dom_lock, flags); + if (zdev->s390_domain->type == IOMMU_DOMAIN_BLOCKED || + zdev->s390_domain->type == IOMMU_DOMAIN_IDENTITY) { + spin_unlock_irqrestore(&zdev->dom_lock, flags); + return; + } + + max_size = max_tbl_size(to_s390_domain(zdev->s390_domain)); + spin_unlock_irqrestore(&zdev->dom_lock, flags); + + if (zdev->end_dma < max_size) { + end_resv = max_size - zdev->end_dma; + region = iommu_alloc_resv_region(zdev->end_dma + 1, end_resv, + 0, IOMMU_RESV_RESERVED, + GFP_KERNEL); if (!region) return; list_add_tail(®ion->list, list); @@ -708,13 +753,9 @@ static struct iommu_device *s390_iommu_probe_device(struct device *dev) zdev = to_zpci_dev(dev); - if (zdev->start_dma > zdev->end_dma || - zdev->start_dma > ZPCI_TABLE_SIZE_RT - 1) + if (zdev->start_dma > zdev->end_dma) return ERR_PTR(-EINVAL); - if (zdev->end_dma > ZPCI_TABLE_SIZE_RT - 1) - zdev->end_dma = ZPCI_TABLE_SIZE_RT - 1; - if (zdev->tlb_refresh) dev->iommu->shadow_on_flush = 1; @@ -999,7 +1040,6 @@ struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev) int zpci_init_iommu(struct zpci_dev *zdev) { - u64 aperture_size; int rc = 0; rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL, @@ -1017,12 +1057,6 @@ int zpci_init_iommu(struct zpci_dev *zdev) if (rc) goto out_sysfs; - zdev->start_dma = PAGE_ALIGN(zdev->start_dma); - aperture_size = min3(s390_iommu_aperture, - ZPCI_TABLE_SIZE_RT - zdev->start_dma, - zdev->end_dma - zdev->start_dma + 1); - zdev->end_dma = zdev->start_dma + aperture_size - 1; - return 0; out_sysfs: