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Diffstat (limited to 'arch/s390/pci/pci_dma.c')
-rw-r--r--arch/s390/pci/pci_dma.c715
1 files changed, 0 insertions, 715 deletions
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
deleted file mode 100644
index f46833a25526..000000000000
--- a/arch/s390/pci/pci_dma.c
+++ /dev/null
@@ -1,715 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright IBM Corp. 2012
- *
- * Author(s):
- * Jan Glauber <jang@linux.vnet.ibm.com>
- */
-
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/export.h>
-#include <linux/iommu-helper.h>
-#include <linux/dma-map-ops.h>
-#include <linux/vmalloc.h>
-#include <linux/pci.h>
-#include <asm/pci_dma.h>
-
-static struct kmem_cache *dma_region_table_cache;
-static struct kmem_cache *dma_page_table_cache;
-static int s390_iommu_strict;
-static u64 s390_iommu_aperture;
-static u32 s390_iommu_aperture_factor = 1;
-
-static int zpci_refresh_global(struct zpci_dev *zdev)
-{
- return zpci_refresh_trans((u64) zdev->fh << 32, zdev->start_dma,
- zdev->iommu_pages * PAGE_SIZE);
-}
-
-unsigned long *dma_alloc_cpu_table(void)
-{
- unsigned long *table, *entry;
-
- table = kmem_cache_alloc(dma_region_table_cache, GFP_ATOMIC);
- if (!table)
- return NULL;
-
- for (entry = table; entry < table + ZPCI_TABLE_ENTRIES; entry++)
- *entry = ZPCI_TABLE_INVALID;
- return table;
-}
-
-static void dma_free_cpu_table(void *table)
-{
- kmem_cache_free(dma_region_table_cache, table);
-}
-
-static unsigned long *dma_alloc_page_table(void)
-{
- unsigned long *table, *entry;
-
- table = kmem_cache_alloc(dma_page_table_cache, GFP_ATOMIC);
- if (!table)
- return NULL;
-
- for (entry = table; entry < table + ZPCI_PT_ENTRIES; entry++)
- *entry = ZPCI_PTE_INVALID;
- return table;
-}
-
-static void dma_free_page_table(void *table)
-{
- kmem_cache_free(dma_page_table_cache, table);
-}
-
-static unsigned long *dma_get_seg_table_origin(unsigned long *entry)
-{
- unsigned long *sto;
-
- if (reg_entry_isvalid(*entry))
- sto = get_rt_sto(*entry);
- else {
- sto = dma_alloc_cpu_table();
- if (!sto)
- return NULL;
-
- set_rt_sto(entry, virt_to_phys(sto));
- validate_rt_entry(entry);
- entry_clr_protected(entry);
- }
- return sto;
-}
-
-static unsigned long *dma_get_page_table_origin(unsigned long *entry)
-{
- unsigned long *pto;
-
- if (reg_entry_isvalid(*entry))
- pto = get_st_pto(*entry);
- else {
- pto = dma_alloc_page_table();
- if (!pto)
- return NULL;
- set_st_pto(entry, virt_to_phys(pto));
- validate_st_entry(entry);
- entry_clr_protected(entry);
- }
- return pto;
-}
-
-unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr)
-{
- unsigned long *sto, *pto;
- unsigned int rtx, sx, px;
-
- rtx = calc_rtx(dma_addr);
- sto = dma_get_seg_table_origin(&rto[rtx]);
- if (!sto)
- return NULL;
-
- sx = calc_sx(dma_addr);
- pto = dma_get_page_table_origin(&sto[sx]);
- if (!pto)
- return NULL;
-
- px = calc_px(dma_addr);
- return &pto[px];
-}
-
-void dma_update_cpu_trans(unsigned long *entry, phys_addr_t page_addr, int flags)
-{
- if (flags & ZPCI_PTE_INVALID) {
- invalidate_pt_entry(entry);
- } else {
- set_pt_pfaa(entry, page_addr);
- validate_pt_entry(entry);
- }
-
- if (flags & ZPCI_TABLE_PROTECTED)
- entry_set_protected(entry);
- else
- entry_clr_protected(entry);
-}
-
-static int __dma_update_trans(struct zpci_dev *zdev, phys_addr_t pa,
- dma_addr_t dma_addr, size_t size, int flags)
-{
- unsigned int nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
- phys_addr_t page_addr = (pa & PAGE_MASK);
- unsigned long irq_flags;
- unsigned long *entry;
- int i, rc = 0;
-
- if (!nr_pages)
- return -EINVAL;
-
- spin_lock_irqsave(&zdev->dma_table_lock, irq_flags);
- if (!zdev->dma_table) {
- rc = -EINVAL;
- goto out_unlock;
- }
-
- for (i = 0; i < nr_pages; i++) {
- entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
- if (!entry) {
- rc = -ENOMEM;
- goto undo_cpu_trans;
- }
- dma_update_cpu_trans(entry, page_addr, flags);
- page_addr += PAGE_SIZE;
- dma_addr += PAGE_SIZE;
- }
-
-undo_cpu_trans:
- if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)) {
- flags = ZPCI_PTE_INVALID;
- while (i-- > 0) {
- page_addr -= PAGE_SIZE;
- dma_addr -= PAGE_SIZE;
- entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
- if (!entry)
- break;
- dma_update_cpu_trans(entry, page_addr, flags);
- }
- }
-out_unlock:
- spin_unlock_irqrestore(&zdev->dma_table_lock, irq_flags);
- return rc;
-}
-
-static int __dma_purge_tlb(struct zpci_dev *zdev, dma_addr_t dma_addr,
- size_t size, int flags)
-{
- unsigned long irqflags;
- int ret;
-
- /*
- * With zdev->tlb_refresh == 0, rpcit is not required to establish new
- * translations when previously invalid translation-table entries are
- * validated. With lazy unmap, rpcit is skipped for previously valid
- * entries, but a global rpcit is then required before any address can
- * be re-used, i.e. after each iommu bitmap wrap-around.
- */
- if ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID) {
- if (!zdev->tlb_refresh)
- return 0;
- } else {
- if (!s390_iommu_strict)
- return 0;
- }
-
- ret = zpci_refresh_trans((u64) zdev->fh << 32, dma_addr,
- PAGE_ALIGN(size));
- if (ret == -ENOMEM && !s390_iommu_strict) {
- /* enable the hypervisor to free some resources */
- if (zpci_refresh_global(zdev))
- goto out;
-
- spin_lock_irqsave(&zdev->iommu_bitmap_lock, irqflags);
- bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
- zdev->lazy_bitmap, zdev->iommu_pages);
- bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
- spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, irqflags);
- ret = 0;
- }
-out:
- return ret;
-}
-
-static int dma_update_trans(struct zpci_dev *zdev, phys_addr_t pa,
- dma_addr_t dma_addr, size_t size, int flags)
-{
- int rc;
-
- rc = __dma_update_trans(zdev, pa, dma_addr, size, flags);
- if (rc)
- return rc;
-
- rc = __dma_purge_tlb(zdev, dma_addr, size, flags);
- if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID))
- __dma_update_trans(zdev, pa, dma_addr, size, ZPCI_PTE_INVALID);
-
- return rc;
-}
-
-void dma_free_seg_table(unsigned long entry)
-{
- unsigned long *sto = get_rt_sto(entry);
- int sx;
-
- for (sx = 0; sx < ZPCI_TABLE_ENTRIES; sx++)
- if (reg_entry_isvalid(sto[sx]))
- dma_free_page_table(get_st_pto(sto[sx]));
-
- dma_free_cpu_table(sto);
-}
-
-void dma_cleanup_tables(unsigned long *table)
-{
- int rtx;
-
- if (!table)
- return;
-
- for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
- if (reg_entry_isvalid(table[rtx]))
- dma_free_seg_table(table[rtx]);
-
- dma_free_cpu_table(table);
-}
-
-static unsigned long __dma_alloc_iommu(struct device *dev,
- unsigned long start, int size)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-
- return iommu_area_alloc(zdev->iommu_bitmap, zdev->iommu_pages,
- start, size, zdev->start_dma >> PAGE_SHIFT,
- dma_get_seg_boundary_nr_pages(dev, PAGE_SHIFT),
- 0);
-}
-
-static dma_addr_t dma_alloc_address(struct device *dev, int size)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- unsigned long offset, flags;
-
- spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
- offset = __dma_alloc_iommu(dev, zdev->next_bit, size);
- if (offset == -1) {
- if (!s390_iommu_strict) {
- /* global flush before DMA addresses are reused */
- if (zpci_refresh_global(zdev))
- goto out_error;
-
- bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
- zdev->lazy_bitmap, zdev->iommu_pages);
- bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
- }
- /* wrap-around */
- offset = __dma_alloc_iommu(dev, 0, size);
- if (offset == -1)
- goto out_error;
- }
- zdev->next_bit = offset + size;
- spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
-
- return zdev->start_dma + offset * PAGE_SIZE;
-
-out_error:
- spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
- return DMA_MAPPING_ERROR;
-}
-
-static void dma_free_address(struct device *dev, dma_addr_t dma_addr, int size)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- unsigned long flags, offset;
-
- offset = (dma_addr - zdev->start_dma) >> PAGE_SHIFT;
-
- spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
- if (!zdev->iommu_bitmap)
- goto out;
-
- if (s390_iommu_strict)
- bitmap_clear(zdev->iommu_bitmap, offset, size);
- else
- bitmap_set(zdev->lazy_bitmap, offset, size);
-
-out:
- spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
-}
-
-static inline void zpci_err_dma(unsigned long rc, unsigned long addr)
-{
- struct {
- unsigned long rc;
- unsigned long addr;
- } __packed data = {rc, addr};
-
- zpci_err_hex(&data, sizeof(data));
-}
-
-static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction direction,
- unsigned long attrs)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- unsigned long pa = page_to_phys(page) + offset;
- int flags = ZPCI_PTE_VALID;
- unsigned long nr_pages;
- dma_addr_t dma_addr;
- int ret;
-
- /* This rounds up number of pages based on size and offset */
- nr_pages = iommu_num_pages(pa, size, PAGE_SIZE);
- dma_addr = dma_alloc_address(dev, nr_pages);
- if (dma_addr == DMA_MAPPING_ERROR) {
- ret = -ENOSPC;
- goto out_err;
- }
-
- /* Use rounded up size */
- size = nr_pages * PAGE_SIZE;
-
- if (direction == DMA_NONE || direction == DMA_TO_DEVICE)
- flags |= ZPCI_TABLE_PROTECTED;
-
- ret = dma_update_trans(zdev, pa, dma_addr, size, flags);
- if (ret)
- goto out_free;
-
- atomic64_add(nr_pages, &zdev->mapped_pages);
- return dma_addr + (offset & ~PAGE_MASK);
-
-out_free:
- dma_free_address(dev, dma_addr, nr_pages);
-out_err:
- zpci_err("map error:\n");
- zpci_err_dma(ret, pa);
- return DMA_MAPPING_ERROR;
-}
-
-static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr,
- size_t size, enum dma_data_direction direction,
- unsigned long attrs)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- int npages, ret;
-
- npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
- dma_addr = dma_addr & PAGE_MASK;
- ret = dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,
- ZPCI_PTE_INVALID);
- if (ret) {
- zpci_err("unmap error:\n");
- zpci_err_dma(ret, dma_addr);
- return;
- }
-
- atomic64_add(npages, &zdev->unmapped_pages);
- dma_free_address(dev, dma_addr, npages);
-}
-
-static void *s390_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag,
- unsigned long attrs)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- struct page *page;
- phys_addr_t pa;
- dma_addr_t map;
-
- size = PAGE_ALIGN(size);
- page = alloc_pages(flag | __GFP_ZERO, get_order(size));
- if (!page)
- return NULL;
-
- pa = page_to_phys(page);
- map = s390_dma_map_pages(dev, page, 0, size, DMA_BIDIRECTIONAL, 0);
- if (dma_mapping_error(dev, map)) {
- __free_pages(page, get_order(size));
- return NULL;
- }
-
- atomic64_add(size / PAGE_SIZE, &zdev->allocated_pages);
- if (dma_handle)
- *dma_handle = map;
- return phys_to_virt(pa);
-}
-
-static void s390_dma_free(struct device *dev, size_t size,
- void *vaddr, dma_addr_t dma_handle,
- unsigned long attrs)
-{
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-
- size = PAGE_ALIGN(size);
- atomic64_sub(size / PAGE_SIZE, &zdev->allocated_pages);
- s390_dma_unmap_pages(dev, dma_handle, size, DMA_BIDIRECTIONAL, 0);
- free_pages((unsigned long)vaddr, get_order(size));
-}
-
-/* Map a segment into a contiguous dma address area */
-static int __s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
- size_t size, dma_addr_t *handle,
- enum dma_data_direction dir)
-{
- unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
- struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
- dma_addr_t dma_addr_base, dma_addr;
- int flags = ZPCI_PTE_VALID;
- struct scatterlist *s;
- phys_addr_t pa = 0;
- int ret;
-
- dma_addr_base = dma_alloc_address(dev, nr_pages);
- if (dma_addr_base == DMA_MAPPING_ERROR)
- return -ENOMEM;
-
- dma_addr = dma_addr_base;
- if (dir == DMA_NONE || dir == DMA_TO_DEVICE)
- flags |= ZPCI_TABLE_PROTECTED;
-
- for (s = sg; dma_addr < dma_addr_base + size; s = sg_next(s)) {
- pa = page_to_phys(sg_page(s));
- ret = __dma_update_trans(zdev, pa, dma_addr,
- s->offset + s->length, flags);
- if (ret)
- goto unmap;
-
- dma_addr += s->offset + s->length;
- }
- ret = __dma_purge_tlb(zdev, dma_addr_base, size, flags);
- if (ret)
- goto unmap;
-
- *handle = dma_addr_base;
- atomic64_add(nr_pages, &zdev->mapped_pages);
-
- return ret;
-
-unmap:
- dma_update_trans(zdev, 0, dma_addr_base, dma_addr - dma_addr_base,
- ZPCI_PTE_INVALID);
- dma_free_address(dev, dma_addr_base, nr_pages);
- zpci_err("map error:\n");
- zpci_err_dma(ret, pa);
- return ret;
-}
-
-static int s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
- int nr_elements, enum dma_data_direction dir,
- unsigned long attrs)
-{
- struct scatterlist *s = sg, *start = sg, *dma = sg;
- unsigned int max = dma_get_max_seg_size(dev);
- unsigned int size = s->offset + s->length;
- unsigned int offset = s->offset;
- int count = 0, i, ret;
-
- for (i = 1; i < nr_elements; i++) {
- s = sg_next(s);
-
- s->dma_length = 0;
-
- if (s->offset || (size & ~PAGE_MASK) ||
- size + s->length > max) {
- ret = __s390_dma_map_sg(dev, start, size,
- &dma->dma_address, dir);
- if (ret)
- goto unmap;
-
- dma->dma_address += offset;
- dma->dma_length = size - offset;
-
- size = offset = s->offset;
- start = s;
- dma = sg_next(dma);
- count++;
- }
- size += s->length;
- }
- ret = __s390_dma_map_sg(dev, start, size, &dma->dma_address, dir);
- if (ret)
- goto unmap;
-
- dma->dma_address += offset;
- dma->dma_length = size - offset;
-
- return count + 1;
-unmap:
- for_each_sg(sg, s, count, i)
- s390_dma_unmap_pages(dev, sg_dma_address(s), sg_dma_len(s),
- dir, attrs);
-
- return ret;
-}
-
-static void s390_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
- int nr_elements, enum dma_data_direction dir,
- unsigned long attrs)
-{
- struct scatterlist *s;
- int i;
-
- for_each_sg(sg, s, nr_elements, i) {
- if (s->dma_length)
- s390_dma_unmap_pages(dev, s->dma_address, s->dma_length,
- dir, attrs);
- s->dma_address = 0;
- s->dma_length = 0;
- }
-}
-
-int zpci_dma_init_device(struct zpci_dev *zdev)
-{
- int rc;
-
- /*
- * At this point, if the device is part of an IOMMU domain, this would
- * be a strong hint towards a bug in the IOMMU API (common) code and/or
- * simultaneous access via IOMMU and DMA API. So let's issue a warning.
- */
- WARN_ON(zdev->s390_domain);
-
- spin_lock_init(&zdev->iommu_bitmap_lock);
- spin_lock_init(&zdev->dma_table_lock);
-
- zdev->dma_table = dma_alloc_cpu_table();
- if (!zdev->dma_table) {
- rc = -ENOMEM;
- goto out;
- }
-
- /*
- * Restrict the iommu bitmap size to the minimum of the following:
- * - s390_iommu_aperture which defaults to high_memory
- * - 3-level pagetable address limit minus start_dma offset
- * - DMA address range allowed by the hardware (clp query pci fn)
- *
- * Also set zdev->end_dma to the actual end address of the usable
- * range, instead of the theoretical maximum as reported by hardware.
- *
- * This limits the number of concurrently usable DMA mappings since
- * for each DMA mapped memory address we need a DMA address including
- * extra DMA addresses for multiple mappings of the same memory address.
- */
- zdev->start_dma = PAGE_ALIGN(zdev->start_dma);
- zdev->iommu_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 + zdev->iommu_size - 1;
- zdev->iommu_pages = zdev->iommu_size >> PAGE_SHIFT;
- zdev->iommu_bitmap = vzalloc(zdev->iommu_pages / 8);
- if (!zdev->iommu_bitmap) {
- rc = -ENOMEM;
- goto free_dma_table;
- }
- if (!s390_iommu_strict) {
- zdev->lazy_bitmap = vzalloc(zdev->iommu_pages / 8);
- if (!zdev->lazy_bitmap) {
- rc = -ENOMEM;
- goto free_bitmap;
- }
-
- }
- if (zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
- virt_to_phys(zdev->dma_table))) {
- rc = -EIO;
- goto free_bitmap;
- }
-
- return 0;
-free_bitmap:
- vfree(zdev->iommu_bitmap);
- zdev->iommu_bitmap = NULL;
- vfree(zdev->lazy_bitmap);
- zdev->lazy_bitmap = NULL;
-free_dma_table:
- dma_free_cpu_table(zdev->dma_table);
- zdev->dma_table = NULL;
-out:
- return rc;
-}
-
-int zpci_dma_exit_device(struct zpci_dev *zdev)
-{
- int cc = 0;
-
- /*
- * At this point, if the device is part of an IOMMU domain, this would
- * be a strong hint towards a bug in the IOMMU API (common) code and/or
- * simultaneous access via IOMMU and DMA API. So let's issue a warning.
- */
- WARN_ON(zdev->s390_domain);
- if (zdev_enabled(zdev))
- cc = zpci_unregister_ioat(zdev, 0);
- /*
- * cc == 3 indicates the function is gone already. This can happen
- * if the function was deconfigured/disabled suddenly and we have not
- * received a new handle yet.
- */
- if (cc && cc != 3)
- return -EIO;
-
- dma_cleanup_tables(zdev->dma_table);
- zdev->dma_table = NULL;
- vfree(zdev->iommu_bitmap);
- zdev->iommu_bitmap = NULL;
- vfree(zdev->lazy_bitmap);
- zdev->lazy_bitmap = NULL;
- zdev->next_bit = 0;
- return 0;
-}
-
-static int __init dma_alloc_cpu_table_caches(void)
-{
- dma_region_table_cache = kmem_cache_create("PCI_DMA_region_tables",
- ZPCI_TABLE_SIZE, ZPCI_TABLE_ALIGN,
- 0, NULL);
- if (!dma_region_table_cache)
- return -ENOMEM;
-
- dma_page_table_cache = kmem_cache_create("PCI_DMA_page_tables",
- ZPCI_PT_SIZE, ZPCI_PT_ALIGN,
- 0, NULL);
- if (!dma_page_table_cache) {
- kmem_cache_destroy(dma_region_table_cache);
- return -ENOMEM;
- }
- return 0;
-}
-
-int __init zpci_dma_init(void)
-{
- s390_iommu_aperture = (u64)high_memory;
- if (!s390_iommu_aperture_factor)
- s390_iommu_aperture = ULONG_MAX;
- else
- s390_iommu_aperture *= s390_iommu_aperture_factor;
-
- return dma_alloc_cpu_table_caches();
-}
-
-void zpci_dma_exit(void)
-{
- kmem_cache_destroy(dma_page_table_cache);
- kmem_cache_destroy(dma_region_table_cache);
-}
-
-const struct dma_map_ops s390_pci_dma_ops = {
- .alloc = s390_dma_alloc,
- .free = s390_dma_free,
- .map_sg = s390_dma_map_sg,
- .unmap_sg = s390_dma_unmap_sg,
- .map_page = s390_dma_map_pages,
- .unmap_page = s390_dma_unmap_pages,
- .mmap = dma_common_mmap,
- .get_sgtable = dma_common_get_sgtable,
- .alloc_pages = dma_common_alloc_pages,
- .free_pages = dma_common_free_pages,
- /* dma_supported is unconditionally true without a callback */
-};
-EXPORT_SYMBOL_GPL(s390_pci_dma_ops);
-
-static int __init s390_iommu_setup(char *str)
-{
- if (!strcmp(str, "strict"))
- s390_iommu_strict = 1;
- return 1;
-}
-
-__setup("s390_iommu=", s390_iommu_setup);
-
-static int __init s390_iommu_aperture_setup(char *str)
-{
- if (kstrtou32(str, 10, &s390_iommu_aperture_factor))
- s390_iommu_aperture_factor = 1;
- return 1;
-}
-
-__setup("s390_iommu_aperture=", s390_iommu_aperture_setup);