532 lines
13 KiB
C
532 lines
13 KiB
C
/*
|
|
* 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-mapping.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 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 | ZPCI_TABLE_PROTECTED;
|
|
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 | ZPCI_TABLE_PROTECTED;
|
|
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, 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, pto);
|
|
validate_st_entry(entry);
|
|
entry_clr_protected(entry);
|
|
}
|
|
return pto;
|
|
}
|
|
|
|
static 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 *dma_table, void *page_addr,
|
|
dma_addr_t dma_addr, int flags)
|
|
{
|
|
unsigned long *entry;
|
|
|
|
entry = dma_walk_cpu_trans(dma_table, dma_addr);
|
|
if (!entry) {
|
|
WARN_ON_ONCE(1);
|
|
return;
|
|
}
|
|
|
|
if (flags & ZPCI_PTE_INVALID) {
|
|
invalidate_pt_entry(entry);
|
|
return;
|
|
} 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, unsigned long pa,
|
|
dma_addr_t dma_addr, size_t size, int flags)
|
|
{
|
|
unsigned int nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
|
|
u8 *page_addr = (u8 *) (pa & PAGE_MASK);
|
|
dma_addr_t start_dma_addr = dma_addr;
|
|
unsigned long irq_flags;
|
|
int i, rc = 0;
|
|
|
|
if (!nr_pages)
|
|
return -EINVAL;
|
|
|
|
spin_lock_irqsave(&zdev->dma_table_lock, irq_flags);
|
|
if (!zdev->dma_table)
|
|
goto no_refresh;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
dma_update_cpu_trans(zdev->dma_table, page_addr, dma_addr,
|
|
flags);
|
|
page_addr += PAGE_SIZE;
|
|
dma_addr += PAGE_SIZE;
|
|
}
|
|
|
|
/*
|
|
* With zdev->tlb_refresh == 0, rpcit is not required to establish new
|
|
* translations when previously invalid translation-table entries are
|
|
* validated. With lazy unmap, it also 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 (!zdev->tlb_refresh &&
|
|
(!s390_iommu_strict ||
|
|
((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)))
|
|
goto no_refresh;
|
|
|
|
rc = zpci_refresh_trans((u64) zdev->fh << 32, start_dma_addr,
|
|
nr_pages * PAGE_SIZE);
|
|
|
|
no_refresh:
|
|
spin_unlock_irqrestore(&zdev->dma_table_lock, irq_flags);
|
|
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 zpci_dev *zdev,
|
|
unsigned long start, int size)
|
|
{
|
|
unsigned long boundary_size;
|
|
|
|
boundary_size = ALIGN(dma_get_seg_boundary(&zdev->pdev->dev) + 1,
|
|
PAGE_SIZE) >> PAGE_SHIFT;
|
|
return iommu_area_alloc(zdev->iommu_bitmap, zdev->iommu_pages,
|
|
start, size, 0, boundary_size, 0);
|
|
}
|
|
|
|
static unsigned long dma_alloc_iommu(struct zpci_dev *zdev, int size)
|
|
{
|
|
unsigned long offset, flags;
|
|
int wrap = 0;
|
|
|
|
spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
|
|
offset = __dma_alloc_iommu(zdev, zdev->next_bit, size);
|
|
if (offset == -1) {
|
|
/* wrap-around */
|
|
offset = __dma_alloc_iommu(zdev, 0, size);
|
|
wrap = 1;
|
|
}
|
|
|
|
if (offset != -1) {
|
|
zdev->next_bit = offset + size;
|
|
if (!zdev->tlb_refresh && !s390_iommu_strict && wrap)
|
|
/* global flush after wrap-around with lazy unmap */
|
|
zpci_refresh_global(zdev);
|
|
}
|
|
spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
|
|
return offset;
|
|
}
|
|
|
|
static void dma_free_iommu(struct zpci_dev *zdev, unsigned long offset, int size)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
|
|
if (!zdev->iommu_bitmap)
|
|
goto out;
|
|
bitmap_clear(zdev->iommu_bitmap, offset, size);
|
|
/*
|
|
* Lazy flush for unmap: need to move next_bit to avoid address re-use
|
|
* until wrap-around.
|
|
*/
|
|
if (!s390_iommu_strict && offset >= zdev->next_bit)
|
|
zdev->next_bit = offset + size;
|
|
out:
|
|
spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
|
|
}
|
|
|
|
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,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
|
|
unsigned long nr_pages, iommu_page_index;
|
|
unsigned long pa = page_to_phys(page) + offset;
|
|
int flags = ZPCI_PTE_VALID;
|
|
dma_addr_t dma_addr;
|
|
|
|
/* This rounds up number of pages based on size and offset */
|
|
nr_pages = iommu_num_pages(pa, size, PAGE_SIZE);
|
|
iommu_page_index = dma_alloc_iommu(zdev, nr_pages);
|
|
if (iommu_page_index == -1)
|
|
goto out_err;
|
|
|
|
/* Use rounded up size */
|
|
size = nr_pages * PAGE_SIZE;
|
|
|
|
dma_addr = zdev->start_dma + iommu_page_index * PAGE_SIZE;
|
|
if (dma_addr + size > zdev->end_dma)
|
|
goto out_free;
|
|
|
|
if (direction == DMA_NONE || direction == DMA_TO_DEVICE)
|
|
flags |= ZPCI_TABLE_PROTECTED;
|
|
|
|
if (!dma_update_trans(zdev, pa, dma_addr, size, flags)) {
|
|
atomic64_add(nr_pages, &zdev->mapped_pages);
|
|
return dma_addr + (offset & ~PAGE_MASK);
|
|
}
|
|
|
|
out_free:
|
|
dma_free_iommu(zdev, iommu_page_index, nr_pages);
|
|
out_err:
|
|
zpci_err("map error:\n");
|
|
zpci_err_hex(&pa, sizeof(pa));
|
|
return DMA_ERROR_CODE;
|
|
}
|
|
|
|
static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr,
|
|
size_t size, enum dma_data_direction direction,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
|
|
unsigned long iommu_page_index;
|
|
int npages;
|
|
|
|
npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
|
|
dma_addr = dma_addr & PAGE_MASK;
|
|
if (dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,
|
|
ZPCI_TABLE_PROTECTED | ZPCI_PTE_INVALID)) {
|
|
zpci_err("unmap error:\n");
|
|
zpci_err_hex(&dma_addr, sizeof(dma_addr));
|
|
}
|
|
|
|
atomic64_add(npages, &zdev->unmapped_pages);
|
|
iommu_page_index = (dma_addr - zdev->start_dma) >> PAGE_SHIFT;
|
|
dma_free_iommu(zdev, iommu_page_index, npages);
|
|
}
|
|
|
|
static void *s390_dma_alloc(struct device *dev, size_t size,
|
|
dma_addr_t *dma_handle, gfp_t flag,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
|
|
struct page *page;
|
|
unsigned long pa;
|
|
dma_addr_t map;
|
|
|
|
size = PAGE_ALIGN(size);
|
|
page = alloc_pages(flag, get_order(size));
|
|
if (!page)
|
|
return NULL;
|
|
|
|
pa = page_to_phys(page);
|
|
memset((void *) pa, 0, size);
|
|
|
|
map = s390_dma_map_pages(dev, page, pa % PAGE_SIZE,
|
|
size, DMA_BIDIRECTIONAL, NULL);
|
|
if (dma_mapping_error(dev, map)) {
|
|
free_pages(pa, get_order(size));
|
|
return NULL;
|
|
}
|
|
|
|
atomic64_add(size / PAGE_SIZE, &zdev->allocated_pages);
|
|
if (dma_handle)
|
|
*dma_handle = map;
|
|
return (void *) pa;
|
|
}
|
|
|
|
static void s390_dma_free(struct device *dev, size_t size,
|
|
void *pa, dma_addr_t dma_handle,
|
|
struct dma_attrs *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, NULL);
|
|
free_pages((unsigned long) pa, get_order(size));
|
|
}
|
|
|
|
static int s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
|
|
int nr_elements, enum dma_data_direction dir,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
int mapped_elements = 0;
|
|
struct scatterlist *s;
|
|
int i;
|
|
|
|
for_each_sg(sg, s, nr_elements, i) {
|
|
struct page *page = sg_page(s);
|
|
s->dma_address = s390_dma_map_pages(dev, page, s->offset,
|
|
s->length, dir, NULL);
|
|
if (!dma_mapping_error(dev, s->dma_address)) {
|
|
s->dma_length = s->length;
|
|
mapped_elements++;
|
|
} else
|
|
goto unmap;
|
|
}
|
|
out:
|
|
return mapped_elements;
|
|
|
|
unmap:
|
|
for_each_sg(sg, s, mapped_elements, i) {
|
|
if (s->dma_address)
|
|
s390_dma_unmap_pages(dev, s->dma_address, s->dma_length,
|
|
dir, NULL);
|
|
s->dma_address = 0;
|
|
s->dma_length = 0;
|
|
}
|
|
mapped_elements = 0;
|
|
goto out;
|
|
}
|
|
|
|
static void s390_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
|
|
int nr_elements, enum dma_data_direction dir,
|
|
struct dma_attrs *attrs)
|
|
{
|
|
struct scatterlist *s;
|
|
int i;
|
|
|
|
for_each_sg(sg, s, nr_elements, i) {
|
|
s390_dma_unmap_pages(dev, s->dma_address, s->dma_length, dir, NULL);
|
|
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_clean;
|
|
}
|
|
|
|
zdev->iommu_size = (unsigned long) high_memory - PAGE_OFFSET;
|
|
zdev->iommu_pages = zdev->iommu_size >> PAGE_SHIFT;
|
|
zdev->iommu_bitmap = vzalloc(zdev->iommu_pages / 8);
|
|
if (!zdev->iommu_bitmap) {
|
|
rc = -ENOMEM;
|
|
goto out_reg;
|
|
}
|
|
|
|
rc = zpci_register_ioat(zdev,
|
|
0,
|
|
zdev->start_dma + PAGE_OFFSET,
|
|
zdev->start_dma + zdev->iommu_size - 1,
|
|
(u64) zdev->dma_table);
|
|
if (rc)
|
|
goto out_reg;
|
|
return 0;
|
|
|
|
out_reg:
|
|
dma_free_cpu_table(zdev->dma_table);
|
|
out_clean:
|
|
return rc;
|
|
}
|
|
|
|
void zpci_dma_exit_device(struct zpci_dev *zdev)
|
|
{
|
|
/*
|
|
* 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);
|
|
|
|
zpci_unregister_ioat(zdev, 0);
|
|
dma_cleanup_tables(zdev->dma_table);
|
|
zdev->dma_table = NULL;
|
|
vfree(zdev->iommu_bitmap);
|
|
zdev->iommu_bitmap = NULL;
|
|
zdev->next_bit = 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)
|
|
{
|
|
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);
|
|
}
|
|
|
|
#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
|
|
|
|
static int __init dma_debug_do_init(void)
|
|
{
|
|
dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
|
|
return 0;
|
|
}
|
|
fs_initcall(dma_debug_do_init);
|
|
|
|
struct dma_map_ops s390_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,
|
|
/* if we support direct DMA this must be conditional */
|
|
.is_phys = 0,
|
|
/* dma_supported is unconditionally true without a callback */
|
|
};
|
|
EXPORT_SYMBOL_GPL(s390_dma_ops);
|
|
|
|
static int __init s390_iommu_setup(char *str)
|
|
{
|
|
if (!strncmp(str, "strict", 6))
|
|
s390_iommu_strict = 1;
|
|
return 0;
|
|
}
|
|
|
|
__setup("s390_iommu=", s390_iommu_setup);
|