mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 17:06:40 +07:00
68c608345c
Instead of providing a special dma_mark_clean hook just for ia64, switch ia64 to use the normal arch_sync_dma_for_cpu hooks instead. This means that we now also set the PG_arch_1 bit for pages in the swiotlb buffer, which isn't stricly needed as we will never execute code out of the swiotlb buffer, but otherwise harmless. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Tony Luck <tony.luck@intel.com>
698 lines
20 KiB
C
698 lines
20 KiB
C
/*
|
|
* Copyright 2010
|
|
* by Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
|
|
*
|
|
* This code provides a IOMMU for Xen PV guests with PCI passthrough.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License v2.0 as published by
|
|
* the Free Software Foundation
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* PV guests under Xen are running in an non-contiguous memory architecture.
|
|
*
|
|
* When PCI pass-through is utilized, this necessitates an IOMMU for
|
|
* translating bus (DMA) to virtual and vice-versa and also providing a
|
|
* mechanism to have contiguous pages for device drivers operations (say DMA
|
|
* operations).
|
|
*
|
|
* Specifically, under Xen the Linux idea of pages is an illusion. It
|
|
* assumes that pages start at zero and go up to the available memory. To
|
|
* help with that, the Linux Xen MMU provides a lookup mechanism to
|
|
* translate the page frame numbers (PFN) to machine frame numbers (MFN)
|
|
* and vice-versa. The MFN are the "real" frame numbers. Furthermore
|
|
* memory is not contiguous. Xen hypervisor stitches memory for guests
|
|
* from different pools, which means there is no guarantee that PFN==MFN
|
|
* and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are
|
|
* allocated in descending order (high to low), meaning the guest might
|
|
* never get any MFN's under the 4GB mark.
|
|
*
|
|
*/
|
|
|
|
#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/memblock.h>
|
|
#include <linux/dma-direct.h>
|
|
#include <linux/export.h>
|
|
#include <xen/swiotlb-xen.h>
|
|
#include <xen/page.h>
|
|
#include <xen/xen-ops.h>
|
|
#include <xen/hvc-console.h>
|
|
|
|
#include <asm/dma-mapping.h>
|
|
#include <asm/xen/page-coherent.h>
|
|
|
|
#include <trace/events/swiotlb.h>
|
|
/*
|
|
* Used to do a quick range check in swiotlb_tbl_unmap_single and
|
|
* swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
|
|
* API.
|
|
*/
|
|
|
|
static char *xen_io_tlb_start, *xen_io_tlb_end;
|
|
static unsigned long xen_io_tlb_nslabs;
|
|
/*
|
|
* Quick lookup value of the bus address of the IOTLB.
|
|
*/
|
|
|
|
static u64 start_dma_addr;
|
|
|
|
/*
|
|
* Both of these functions should avoid XEN_PFN_PHYS because phys_addr_t
|
|
* can be 32bit when dma_addr_t is 64bit leading to a loss in
|
|
* information if the shift is done before casting to 64bit.
|
|
*/
|
|
static inline dma_addr_t xen_phys_to_bus(phys_addr_t paddr)
|
|
{
|
|
unsigned long bfn = pfn_to_bfn(XEN_PFN_DOWN(paddr));
|
|
dma_addr_t dma = (dma_addr_t)bfn << XEN_PAGE_SHIFT;
|
|
|
|
dma |= paddr & ~XEN_PAGE_MASK;
|
|
|
|
return dma;
|
|
}
|
|
|
|
static inline phys_addr_t xen_bus_to_phys(dma_addr_t baddr)
|
|
{
|
|
unsigned long xen_pfn = bfn_to_pfn(XEN_PFN_DOWN(baddr));
|
|
dma_addr_t dma = (dma_addr_t)xen_pfn << XEN_PAGE_SHIFT;
|
|
phys_addr_t paddr = dma;
|
|
|
|
paddr |= baddr & ~XEN_PAGE_MASK;
|
|
|
|
return paddr;
|
|
}
|
|
|
|
static inline dma_addr_t xen_virt_to_bus(void *address)
|
|
{
|
|
return xen_phys_to_bus(virt_to_phys(address));
|
|
}
|
|
|
|
static int check_pages_physically_contiguous(unsigned long xen_pfn,
|
|
unsigned int offset,
|
|
size_t length)
|
|
{
|
|
unsigned long next_bfn;
|
|
int i;
|
|
int nr_pages;
|
|
|
|
next_bfn = pfn_to_bfn(xen_pfn);
|
|
nr_pages = (offset + length + XEN_PAGE_SIZE-1) >> XEN_PAGE_SHIFT;
|
|
|
|
for (i = 1; i < nr_pages; i++) {
|
|
if (pfn_to_bfn(++xen_pfn) != ++next_bfn)
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
static inline int range_straddles_page_boundary(phys_addr_t p, size_t size)
|
|
{
|
|
unsigned long xen_pfn = XEN_PFN_DOWN(p);
|
|
unsigned int offset = p & ~XEN_PAGE_MASK;
|
|
|
|
if (offset + size <= XEN_PAGE_SIZE)
|
|
return 0;
|
|
if (check_pages_physically_contiguous(xen_pfn, offset, size))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int is_xen_swiotlb_buffer(dma_addr_t dma_addr)
|
|
{
|
|
unsigned long bfn = XEN_PFN_DOWN(dma_addr);
|
|
unsigned long xen_pfn = bfn_to_local_pfn(bfn);
|
|
phys_addr_t paddr = XEN_PFN_PHYS(xen_pfn);
|
|
|
|
/* If the address is outside our domain, it CAN
|
|
* have the same virtual address as another address
|
|
* in our domain. Therefore _only_ check address within our domain.
|
|
*/
|
|
if (pfn_valid(PFN_DOWN(paddr))) {
|
|
return paddr >= virt_to_phys(xen_io_tlb_start) &&
|
|
paddr < virt_to_phys(xen_io_tlb_end);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int max_dma_bits = 32;
|
|
|
|
static int
|
|
xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs)
|
|
{
|
|
int i, rc;
|
|
int dma_bits;
|
|
dma_addr_t dma_handle;
|
|
phys_addr_t p = virt_to_phys(buf);
|
|
|
|
dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT;
|
|
|
|
i = 0;
|
|
do {
|
|
int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE);
|
|
|
|
do {
|
|
rc = xen_create_contiguous_region(
|
|
p + (i << IO_TLB_SHIFT),
|
|
get_order(slabs << IO_TLB_SHIFT),
|
|
dma_bits, &dma_handle);
|
|
} while (rc && dma_bits++ < max_dma_bits);
|
|
if (rc)
|
|
return rc;
|
|
|
|
i += slabs;
|
|
} while (i < nslabs);
|
|
return 0;
|
|
}
|
|
static unsigned long xen_set_nslabs(unsigned long nr_tbl)
|
|
{
|
|
if (!nr_tbl) {
|
|
xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT);
|
|
xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE);
|
|
} else
|
|
xen_io_tlb_nslabs = nr_tbl;
|
|
|
|
return xen_io_tlb_nslabs << IO_TLB_SHIFT;
|
|
}
|
|
|
|
enum xen_swiotlb_err {
|
|
XEN_SWIOTLB_UNKNOWN = 0,
|
|
XEN_SWIOTLB_ENOMEM,
|
|
XEN_SWIOTLB_EFIXUP
|
|
};
|
|
|
|
static const char *xen_swiotlb_error(enum xen_swiotlb_err err)
|
|
{
|
|
switch (err) {
|
|
case XEN_SWIOTLB_ENOMEM:
|
|
return "Cannot allocate Xen-SWIOTLB buffer\n";
|
|
case XEN_SWIOTLB_EFIXUP:
|
|
return "Failed to get contiguous memory for DMA from Xen!\n"\
|
|
"You either: don't have the permissions, do not have"\
|
|
" enough free memory under 4GB, or the hypervisor memory"\
|
|
" is too fragmented!";
|
|
default:
|
|
break;
|
|
}
|
|
return "";
|
|
}
|
|
int __ref xen_swiotlb_init(int verbose, bool early)
|
|
{
|
|
unsigned long bytes, order;
|
|
int rc = -ENOMEM;
|
|
enum xen_swiotlb_err m_ret = XEN_SWIOTLB_UNKNOWN;
|
|
unsigned int repeat = 3;
|
|
|
|
xen_io_tlb_nslabs = swiotlb_nr_tbl();
|
|
retry:
|
|
bytes = xen_set_nslabs(xen_io_tlb_nslabs);
|
|
order = get_order(xen_io_tlb_nslabs << IO_TLB_SHIFT);
|
|
/*
|
|
* Get IO TLB memory from any location.
|
|
*/
|
|
if (early)
|
|
xen_io_tlb_start = memblock_alloc(PAGE_ALIGN(bytes),
|
|
PAGE_SIZE);
|
|
else {
|
|
#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
|
|
#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
|
|
while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
|
|
xen_io_tlb_start = (void *)xen_get_swiotlb_free_pages(order);
|
|
if (xen_io_tlb_start)
|
|
break;
|
|
order--;
|
|
}
|
|
if (order != get_order(bytes)) {
|
|
pr_warn("Warning: only able to allocate %ld MB for software IO TLB\n",
|
|
(PAGE_SIZE << order) >> 20);
|
|
xen_io_tlb_nslabs = SLABS_PER_PAGE << order;
|
|
bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT;
|
|
}
|
|
}
|
|
if (!xen_io_tlb_start) {
|
|
m_ret = XEN_SWIOTLB_ENOMEM;
|
|
goto error;
|
|
}
|
|
xen_io_tlb_end = xen_io_tlb_start + bytes;
|
|
/*
|
|
* And replace that memory with pages under 4GB.
|
|
*/
|
|
rc = xen_swiotlb_fixup(xen_io_tlb_start,
|
|
bytes,
|
|
xen_io_tlb_nslabs);
|
|
if (rc) {
|
|
if (early)
|
|
memblock_free(__pa(xen_io_tlb_start),
|
|
PAGE_ALIGN(bytes));
|
|
else {
|
|
free_pages((unsigned long)xen_io_tlb_start, order);
|
|
xen_io_tlb_start = NULL;
|
|
}
|
|
m_ret = XEN_SWIOTLB_EFIXUP;
|
|
goto error;
|
|
}
|
|
start_dma_addr = xen_virt_to_bus(xen_io_tlb_start);
|
|
if (early) {
|
|
if (swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs,
|
|
verbose))
|
|
panic("Cannot allocate SWIOTLB buffer");
|
|
rc = 0;
|
|
} else
|
|
rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs);
|
|
|
|
if (!rc)
|
|
swiotlb_set_max_segment(PAGE_SIZE);
|
|
|
|
return rc;
|
|
error:
|
|
if (repeat--) {
|
|
xen_io_tlb_nslabs = max(1024UL, /* Min is 2MB */
|
|
(xen_io_tlb_nslabs >> 1));
|
|
pr_info("Lowering to %luMB\n",
|
|
(xen_io_tlb_nslabs << IO_TLB_SHIFT) >> 20);
|
|
goto retry;
|
|
}
|
|
pr_err("%s (rc:%d)\n", xen_swiotlb_error(m_ret), rc);
|
|
if (early)
|
|
panic("%s (rc:%d)", xen_swiotlb_error(m_ret), rc);
|
|
else
|
|
free_pages((unsigned long)xen_io_tlb_start, order);
|
|
return rc;
|
|
}
|
|
|
|
static void *
|
|
xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
|
|
dma_addr_t *dma_handle, gfp_t flags,
|
|
unsigned long attrs)
|
|
{
|
|
void *ret;
|
|
int order = get_order(size);
|
|
u64 dma_mask = DMA_BIT_MASK(32);
|
|
phys_addr_t phys;
|
|
dma_addr_t dev_addr;
|
|
|
|
/*
|
|
* Ignore region specifiers - the kernel's ideas of
|
|
* pseudo-phys memory layout has nothing to do with the
|
|
* machine physical layout. We can't allocate highmem
|
|
* because we can't return a pointer to it.
|
|
*/
|
|
flags &= ~(__GFP_DMA | __GFP_HIGHMEM);
|
|
|
|
/* Convert the size to actually allocated. */
|
|
size = 1UL << (order + XEN_PAGE_SHIFT);
|
|
|
|
/* On ARM this function returns an ioremap'ped virtual address for
|
|
* which virt_to_phys doesn't return the corresponding physical
|
|
* address. In fact on ARM virt_to_phys only works for kernel direct
|
|
* mapped RAM memory. Also see comment below.
|
|
*/
|
|
ret = xen_alloc_coherent_pages(hwdev, size, dma_handle, flags, attrs);
|
|
|
|
if (!ret)
|
|
return ret;
|
|
|
|
if (hwdev && hwdev->coherent_dma_mask)
|
|
dma_mask = hwdev->coherent_dma_mask;
|
|
|
|
/* At this point dma_handle is the physical address, next we are
|
|
* going to set it to the machine address.
|
|
* Do not use virt_to_phys(ret) because on ARM it doesn't correspond
|
|
* to *dma_handle. */
|
|
phys = *dma_handle;
|
|
dev_addr = xen_phys_to_bus(phys);
|
|
if (((dev_addr + size - 1 <= dma_mask)) &&
|
|
!range_straddles_page_boundary(phys, size))
|
|
*dma_handle = dev_addr;
|
|
else {
|
|
if (xen_create_contiguous_region(phys, order,
|
|
fls64(dma_mask), dma_handle) != 0) {
|
|
xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs);
|
|
return NULL;
|
|
}
|
|
}
|
|
memset(ret, 0, size);
|
|
return ret;
|
|
}
|
|
|
|
static void
|
|
xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
|
|
dma_addr_t dev_addr, unsigned long attrs)
|
|
{
|
|
int order = get_order(size);
|
|
phys_addr_t phys;
|
|
u64 dma_mask = DMA_BIT_MASK(32);
|
|
|
|
if (hwdev && hwdev->coherent_dma_mask)
|
|
dma_mask = hwdev->coherent_dma_mask;
|
|
|
|
/* do not use virt_to_phys because on ARM it doesn't return you the
|
|
* physical address */
|
|
phys = xen_bus_to_phys(dev_addr);
|
|
|
|
/* Convert the size to actually allocated. */
|
|
size = 1UL << (order + XEN_PAGE_SHIFT);
|
|
|
|
if (((dev_addr + size - 1 <= dma_mask)) ||
|
|
range_straddles_page_boundary(phys, size))
|
|
xen_destroy_contiguous_region(phys, order);
|
|
|
|
xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs);
|
|
}
|
|
|
|
/*
|
|
* Map a single buffer of the indicated size for DMA in streaming mode. The
|
|
* physical address to use is returned.
|
|
*
|
|
* Once the device is given the dma address, the device owns this memory until
|
|
* either xen_swiotlb_unmap_page or xen_swiotlb_dma_sync_single is performed.
|
|
*/
|
|
static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
|
|
unsigned long offset, size_t size,
|
|
enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
phys_addr_t map, phys = page_to_phys(page) + offset;
|
|
dma_addr_t dev_addr = xen_phys_to_bus(phys);
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
/*
|
|
* If the address happens to be in the device's DMA window,
|
|
* we can safely return the device addr and not worry about bounce
|
|
* buffering it.
|
|
*/
|
|
if (dma_capable(dev, dev_addr, size) &&
|
|
!range_straddles_page_boundary(phys, size) &&
|
|
!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
|
|
(swiotlb_force != SWIOTLB_FORCE)) {
|
|
/* we are not interested in the dma_addr returned by
|
|
* xen_dma_map_page, only in the potential cache flushes executed
|
|
* by the function. */
|
|
xen_dma_map_page(dev, page, dev_addr, offset, size, dir, attrs);
|
|
return dev_addr;
|
|
}
|
|
|
|
/*
|
|
* Oh well, have to allocate and map a bounce buffer.
|
|
*/
|
|
trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
|
|
|
|
map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, size, dir,
|
|
attrs);
|
|
if (map == DMA_MAPPING_ERROR)
|
|
return DMA_MAPPING_ERROR;
|
|
|
|
dev_addr = xen_phys_to_bus(map);
|
|
xen_dma_map_page(dev, pfn_to_page(map >> PAGE_SHIFT),
|
|
dev_addr, map & ~PAGE_MASK, size, dir, attrs);
|
|
|
|
/*
|
|
* Ensure that the address returned is DMA'ble
|
|
*/
|
|
if (dma_capable(dev, dev_addr, size))
|
|
return dev_addr;
|
|
|
|
attrs |= DMA_ATTR_SKIP_CPU_SYNC;
|
|
swiotlb_tbl_unmap_single(dev, map, size, dir, attrs);
|
|
|
|
return DMA_MAPPING_ERROR;
|
|
}
|
|
|
|
/*
|
|
* Unmap a single streaming mode DMA translation. The dma_addr and size must
|
|
* match what was provided for in a previous xen_swiotlb_map_page call. All
|
|
* other usages are undefined.
|
|
*
|
|
* After this call, reads by the cpu to the buffer are guaranteed to see
|
|
* whatever the device wrote there.
|
|
*/
|
|
static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr,
|
|
size_t size, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
phys_addr_t paddr = xen_bus_to_phys(dev_addr);
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
|
|
xen_dma_unmap_page(hwdev, dev_addr, size, dir, attrs);
|
|
|
|
/* NOTE: We use dev_addr here, not paddr! */
|
|
if (is_xen_swiotlb_buffer(dev_addr))
|
|
swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs);
|
|
}
|
|
|
|
static void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
|
|
size_t size, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
xen_unmap_single(hwdev, dev_addr, size, dir, attrs);
|
|
}
|
|
|
|
/*
|
|
* Make physical memory consistent for a single streaming mode DMA translation
|
|
* after a transfer.
|
|
*
|
|
* If you perform a xen_swiotlb_map_page() but wish to interrogate the buffer
|
|
* using the cpu, yet do not wish to teardown the dma mapping, you must
|
|
* call this function before doing so. At the next point you give the dma
|
|
* address back to the card, you must first perform a
|
|
* xen_swiotlb_dma_sync_for_device, and then the device again owns the buffer
|
|
*/
|
|
static void
|
|
xen_swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
|
|
size_t size, enum dma_data_direction dir,
|
|
enum dma_sync_target target)
|
|
{
|
|
phys_addr_t paddr = xen_bus_to_phys(dev_addr);
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
|
|
if (target == SYNC_FOR_CPU)
|
|
xen_dma_sync_single_for_cpu(hwdev, dev_addr, size, dir);
|
|
|
|
/* NOTE: We use dev_addr here, not paddr! */
|
|
if (is_xen_swiotlb_buffer(dev_addr))
|
|
swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
|
|
|
|
if (target == SYNC_FOR_DEVICE)
|
|
xen_dma_sync_single_for_device(hwdev, dev_addr, size, dir);
|
|
}
|
|
|
|
void
|
|
xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
|
|
size_t size, enum dma_data_direction dir)
|
|
{
|
|
xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
|
|
}
|
|
|
|
void
|
|
xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
|
|
size_t size, enum dma_data_direction dir)
|
|
{
|
|
xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
|
|
}
|
|
|
|
/*
|
|
* Unmap a set of streaming mode DMA translations. Again, cpu read rules
|
|
* concerning calls here are the same as for swiotlb_unmap_page() above.
|
|
*/
|
|
static void
|
|
xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
|
|
for_each_sg(sgl, sg, nelems, i)
|
|
xen_unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir, attrs);
|
|
|
|
}
|
|
|
|
/*
|
|
* Map a set of buffers described by scatterlist in streaming mode for DMA.
|
|
* This is the scatter-gather version of the above xen_swiotlb_map_page
|
|
* interface. Here the scatter gather list elements are each tagged with the
|
|
* appropriate dma address and length. They are obtained via
|
|
* sg_dma_{address,length}(SG).
|
|
*
|
|
* NOTE: An implementation may be able to use a smaller number of
|
|
* DMA address/length pairs than there are SG table elements.
|
|
* (for example via virtual mapping capabilities)
|
|
* The routine returns the number of addr/length pairs actually
|
|
* used, at most nents.
|
|
*
|
|
* Device ownership issues as mentioned above for xen_swiotlb_map_page are the
|
|
* same here.
|
|
*/
|
|
static int
|
|
xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
unsigned long attrs)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
|
|
for_each_sg(sgl, sg, nelems, i) {
|
|
phys_addr_t paddr = sg_phys(sg);
|
|
dma_addr_t dev_addr = xen_phys_to_bus(paddr);
|
|
|
|
if (swiotlb_force == SWIOTLB_FORCE ||
|
|
xen_arch_need_swiotlb(hwdev, paddr, dev_addr) ||
|
|
!dma_capable(hwdev, dev_addr, sg->length) ||
|
|
range_straddles_page_boundary(paddr, sg->length)) {
|
|
phys_addr_t map = swiotlb_tbl_map_single(hwdev,
|
|
start_dma_addr,
|
|
sg_phys(sg),
|
|
sg->length,
|
|
dir, attrs);
|
|
if (map == DMA_MAPPING_ERROR) {
|
|
dev_warn(hwdev, "swiotlb buffer is full\n");
|
|
/* Don't panic here, we expect map_sg users
|
|
to do proper error handling. */
|
|
attrs |= DMA_ATTR_SKIP_CPU_SYNC;
|
|
xen_swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
|
|
attrs);
|
|
sg_dma_len(sgl) = 0;
|
|
return 0;
|
|
}
|
|
dev_addr = xen_phys_to_bus(map);
|
|
xen_dma_map_page(hwdev, pfn_to_page(map >> PAGE_SHIFT),
|
|
dev_addr,
|
|
map & ~PAGE_MASK,
|
|
sg->length,
|
|
dir,
|
|
attrs);
|
|
sg->dma_address = dev_addr;
|
|
} else {
|
|
/* we are not interested in the dma_addr returned by
|
|
* xen_dma_map_page, only in the potential cache flushes executed
|
|
* by the function. */
|
|
xen_dma_map_page(hwdev, pfn_to_page(paddr >> PAGE_SHIFT),
|
|
dev_addr,
|
|
paddr & ~PAGE_MASK,
|
|
sg->length,
|
|
dir,
|
|
attrs);
|
|
sg->dma_address = dev_addr;
|
|
}
|
|
sg_dma_len(sg) = sg->length;
|
|
}
|
|
return nelems;
|
|
}
|
|
|
|
/*
|
|
* Make physical memory consistent for a set of streaming mode DMA translations
|
|
* after a transfer.
|
|
*
|
|
* The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
|
|
* and usage.
|
|
*/
|
|
static void
|
|
xen_swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
|
|
int nelems, enum dma_data_direction dir,
|
|
enum dma_sync_target target)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
for_each_sg(sgl, sg, nelems, i)
|
|
xen_swiotlb_sync_single(hwdev, sg->dma_address,
|
|
sg_dma_len(sg), dir, target);
|
|
}
|
|
|
|
static void
|
|
xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
|
|
int nelems, enum dma_data_direction dir)
|
|
{
|
|
xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
|
|
}
|
|
|
|
static void
|
|
xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
|
|
int nelems, enum dma_data_direction dir)
|
|
{
|
|
xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
|
|
}
|
|
|
|
/*
|
|
* Return whether the given device DMA address mask can be supported
|
|
* properly. For example, if your device can only drive the low 24-bits
|
|
* during bus mastering, then you would pass 0x00ffffff as the mask to
|
|
* this function.
|
|
*/
|
|
static int
|
|
xen_swiotlb_dma_supported(struct device *hwdev, u64 mask)
|
|
{
|
|
return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask;
|
|
}
|
|
|
|
/*
|
|
* Create userspace mapping for the DMA-coherent memory.
|
|
* This function should be called with the pages from the current domain only,
|
|
* passing pages mapped from other domains would lead to memory corruption.
|
|
*/
|
|
static int
|
|
xen_swiotlb_dma_mmap(struct device *dev, struct vm_area_struct *vma,
|
|
void *cpu_addr, dma_addr_t dma_addr, size_t size,
|
|
unsigned long attrs)
|
|
{
|
|
#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
|
|
if (xen_get_dma_ops(dev)->mmap)
|
|
return xen_get_dma_ops(dev)->mmap(dev, vma, cpu_addr,
|
|
dma_addr, size, attrs);
|
|
#endif
|
|
return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
|
|
}
|
|
|
|
/*
|
|
* This function should be called with the pages from the current domain only,
|
|
* passing pages mapped from other domains would lead to memory corruption.
|
|
*/
|
|
static int
|
|
xen_swiotlb_get_sgtable(struct device *dev, struct sg_table *sgt,
|
|
void *cpu_addr, dma_addr_t handle, size_t size,
|
|
unsigned long attrs)
|
|
{
|
|
#if defined(CONFIG_ARM) || defined(CONFIG_ARM64)
|
|
if (xen_get_dma_ops(dev)->get_sgtable) {
|
|
#if 0
|
|
/*
|
|
* This check verifies that the page belongs to the current domain and
|
|
* is not one mapped from another domain.
|
|
* This check is for debug only, and should not go to production build
|
|
*/
|
|
unsigned long bfn = PHYS_PFN(dma_to_phys(dev, handle));
|
|
BUG_ON (!page_is_ram(bfn));
|
|
#endif
|
|
return xen_get_dma_ops(dev)->get_sgtable(dev, sgt, cpu_addr,
|
|
handle, size, attrs);
|
|
}
|
|
#endif
|
|
return dma_common_get_sgtable(dev, sgt, cpu_addr, handle, size, attrs);
|
|
}
|
|
|
|
const struct dma_map_ops xen_swiotlb_dma_ops = {
|
|
.alloc = xen_swiotlb_alloc_coherent,
|
|
.free = xen_swiotlb_free_coherent,
|
|
.sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu,
|
|
.sync_single_for_device = xen_swiotlb_sync_single_for_device,
|
|
.sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu,
|
|
.sync_sg_for_device = xen_swiotlb_sync_sg_for_device,
|
|
.map_sg = xen_swiotlb_map_sg_attrs,
|
|
.unmap_sg = xen_swiotlb_unmap_sg_attrs,
|
|
.map_page = xen_swiotlb_map_page,
|
|
.unmap_page = xen_swiotlb_unmap_page,
|
|
.dma_supported = xen_swiotlb_dma_supported,
|
|
.mmap = xen_swiotlb_dma_mmap,
|
|
.get_sgtable = xen_swiotlb_get_sgtable,
|
|
};
|