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-rw-r--r--kernel/dma/direct.c2
-rw-r--r--kernel/dma/swiotlb.c326
2 files changed, 62 insertions, 266 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 87a6bc2a96c0..f14c376937e5 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -14,8 +14,6 @@
#include <linux/pfn.h>
#include <linux/set_memory.h>
-#define DIRECT_MAPPING_ERROR 0
-
/*
* Most architectures use ZONE_DMA for the first 16 Megabytes, but
* some use it for entirely different regions:
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 4f8a6dbf0b60..ebecaf255ea2 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -21,6 +21,7 @@
#include <linux/cache.h>
#include <linux/dma-direct.h>
+#include <linux/dma-noncoherent.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/spinlock.h>
@@ -73,13 +74,6 @@ static phys_addr_t io_tlb_start, io_tlb_end;
static unsigned long io_tlb_nslabs;
/*
- * When the IOMMU overflows we return a fallback buffer. This sets the size.
- */
-static unsigned long io_tlb_overflow = 32*1024;
-
-static phys_addr_t io_tlb_overflow_buffer;
-
-/*
* This is a free list describing the number of free entries available from
* each index
*/
@@ -126,7 +120,6 @@ setup_io_tlb_npages(char *str)
return 0;
}
early_param("swiotlb", setup_io_tlb_npages);
-/* make io_tlb_overflow tunable too? */
unsigned long swiotlb_nr_tbl(void)
{
@@ -194,16 +187,10 @@ void __init swiotlb_update_mem_attributes(void)
bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT);
set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
memset(vaddr, 0, bytes);
-
- vaddr = phys_to_virt(io_tlb_overflow_buffer);
- bytes = PAGE_ALIGN(io_tlb_overflow);
- set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);
- memset(vaddr, 0, bytes);
}
int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
{
- void *v_overflow_buffer;
unsigned long i, bytes;
bytes = nslabs << IO_TLB_SHIFT;
@@ -213,17 +200,6 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
io_tlb_end = io_tlb_start + bytes;
/*
- * Get the overflow emergency buffer
- */
- v_overflow_buffer = memblock_virt_alloc_low_nopanic(
- PAGE_ALIGN(io_tlb_overflow),
- PAGE_SIZE);
- if (!v_overflow_buffer)
- return -ENOMEM;
-
- io_tlb_overflow_buffer = __pa(v_overflow_buffer);
-
- /*
* Allocate and initialize the free list array. This array is used
* to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
* between io_tlb_start and io_tlb_end.
@@ -330,7 +306,6 @@ int
swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
unsigned long i, bytes;
- unsigned char *v_overflow_buffer;
bytes = nslabs << IO_TLB_SHIFT;
@@ -342,19 +317,6 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
memset(tlb, 0, bytes);
/*
- * Get the overflow emergency buffer
- */
- v_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
- get_order(io_tlb_overflow));
- if (!v_overflow_buffer)
- goto cleanup2;
-
- set_memory_decrypted((unsigned long)v_overflow_buffer,
- io_tlb_overflow >> PAGE_SHIFT);
- memset(v_overflow_buffer, 0, io_tlb_overflow);
- io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer);
-
- /*
* Allocate and initialize the free list array. This array is used
* to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
* between io_tlb_start and io_tlb_end.
@@ -390,10 +352,6 @@ cleanup4:
sizeof(int)));
io_tlb_list = NULL;
cleanup3:
- free_pages((unsigned long)v_overflow_buffer,
- get_order(io_tlb_overflow));
- io_tlb_overflow_buffer = 0;
-cleanup2:
io_tlb_end = 0;
io_tlb_start = 0;
io_tlb_nslabs = 0;
@@ -407,8 +365,6 @@ void __init swiotlb_exit(void)
return;
if (late_alloc) {
- free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer),
- get_order(io_tlb_overflow));
free_pages((unsigned long)io_tlb_orig_addr,
get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
@@ -416,8 +372,6 @@ void __init swiotlb_exit(void)
free_pages((unsigned long)phys_to_virt(io_tlb_start),
get_order(io_tlb_nslabs << IO_TLB_SHIFT));
} else {
- memblock_free_late(io_tlb_overflow_buffer,
- PAGE_ALIGN(io_tlb_overflow));
memblock_free_late(__pa(io_tlb_orig_addr),
PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)));
memblock_free_late(__pa(io_tlb_list),
@@ -429,7 +383,7 @@ void __init swiotlb_exit(void)
max_segment = 0;
}
-int is_swiotlb_buffer(phys_addr_t paddr)
+static int is_swiotlb_buffer(phys_addr_t paddr)
{
return paddr >= io_tlb_start && paddr < io_tlb_end;
}
@@ -591,26 +545,6 @@ found:
}
/*
- * Allocates bounce buffer and returns its physical address.
- */
-static phys_addr_t
-map_single(struct device *hwdev, phys_addr_t phys, size_t size,
- enum dma_data_direction dir, unsigned long attrs)
-{
- dma_addr_t start_dma_addr;
-
- if (swiotlb_force == SWIOTLB_NO_FORCE) {
- dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n",
- &phys);
- return SWIOTLB_MAP_ERROR;
- }
-
- start_dma_addr = __phys_to_dma(hwdev, io_tlb_start);
- return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size,
- dir, attrs);
-}
-
-/*
* tlb_addr is the physical address of the bounce buffer to unmap.
*/
void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
@@ -689,104 +623,32 @@ void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
}
}
-static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr,
- size_t size)
-{
- u64 mask = DMA_BIT_MASK(32);
-
- if (dev && dev->coherent_dma_mask)
- mask = dev->coherent_dma_mask;
- return addr + size - 1 <= mask;
-}
-
-static void *
-swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle,
- unsigned long attrs)
+static dma_addr_t swiotlb_bounce_page(struct device *dev, phys_addr_t *phys,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
{
- phys_addr_t phys_addr;
-
- if (swiotlb_force == SWIOTLB_NO_FORCE)
- goto out_warn;
-
- phys_addr = swiotlb_tbl_map_single(dev,
- __phys_to_dma(dev, io_tlb_start),
- 0, size, DMA_FROM_DEVICE, attrs);
- if (phys_addr == SWIOTLB_MAP_ERROR)
- goto out_warn;
-
- *dma_handle = __phys_to_dma(dev, phys_addr);
- if (!dma_coherent_ok(dev, *dma_handle, size))
- goto out_unmap;
-
- memset(phys_to_virt(phys_addr), 0, size);
- return phys_to_virt(phys_addr);
+ dma_addr_t dma_addr;
-out_unmap:
- dev_warn(dev, "hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
- (unsigned long long)dev->coherent_dma_mask,
- (unsigned long long)*dma_handle);
-
- /*
- * DMA_TO_DEVICE to avoid memcpy in unmap_single.
- * DMA_ATTR_SKIP_CPU_SYNC is optional.
- */
- swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE,
- DMA_ATTR_SKIP_CPU_SYNC);
-out_warn:
- if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) {
- dev_warn(dev,
- "swiotlb: coherent allocation failed, size=%zu\n",
- size);
- dump_stack();
+ if (unlikely(swiotlb_force == SWIOTLB_NO_FORCE)) {
+ dev_warn_ratelimited(dev,
+ "Cannot do DMA to address %pa\n", phys);
+ return DIRECT_MAPPING_ERROR;
}
- return NULL;
-}
-
-static bool swiotlb_free_buffer(struct device *dev, size_t size,
- dma_addr_t dma_addr)
-{
- phys_addr_t phys_addr = dma_to_phys(dev, dma_addr);
- WARN_ON_ONCE(irqs_disabled());
-
- if (!is_swiotlb_buffer(phys_addr))
- return false;
-
- /*
- * DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single.
- * DMA_ATTR_SKIP_CPU_SYNC is optional.
- */
- swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE,
- DMA_ATTR_SKIP_CPU_SYNC);
- return true;
-}
-
-static void
-swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
- int do_panic)
-{
- if (swiotlb_force == SWIOTLB_NO_FORCE)
- return;
-
- /*
- * Ran out of IOMMU space for this operation. This is very bad.
- * Unfortunately the drivers cannot handle this operation properly.
- * unless they check for dma_mapping_error (most don't)
- * When the mapping is small enough return a static buffer to limit
- * the damage, or panic when the transfer is too big.
- */
- dev_err_ratelimited(dev, "DMA: Out of SW-IOMMU space for %zu bytes\n",
- size);
+ /* Oh well, have to allocate and map a bounce buffer. */
+ *phys = swiotlb_tbl_map_single(dev, __phys_to_dma(dev, io_tlb_start),
+ *phys, size, dir, attrs);
+ if (*phys == SWIOTLB_MAP_ERROR)
+ return DIRECT_MAPPING_ERROR;
- if (size <= io_tlb_overflow || !do_panic)
- return;
+ /* Ensure that the address returned is DMA'ble */
+ dma_addr = __phys_to_dma(dev, *phys);
+ if (unlikely(!dma_capable(dev, dma_addr, size))) {
+ swiotlb_tbl_unmap_single(dev, *phys, size, dir,
+ attrs | DMA_ATTR_SKIP_CPU_SYNC);
+ return DIRECT_MAPPING_ERROR;
+ }
- if (dir == DMA_BIDIRECTIONAL)
- panic("DMA: Random memory could be DMA accessed\n");
- if (dir == DMA_FROM_DEVICE)
- panic("DMA: Random memory could be DMA written\n");
- if (dir == DMA_TO_DEVICE)
- panic("DMA: Random memory could be DMA read\n");
+ return dma_addr;
}
/*
@@ -801,7 +663,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
enum dma_data_direction dir,
unsigned long attrs)
{
- phys_addr_t map, phys = page_to_phys(page) + offset;
+ phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dev_addr = phys_to_dma(dev, phys);
BUG_ON(dir == DMA_NONE);
@@ -810,28 +672,17 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
* we can safely return the device addr and not worry about bounce
* buffering it.
*/
- if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE)
- return dev_addr;
-
- trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
-
- /* Oh well, have to allocate and map a bounce buffer. */
- map = map_single(dev, phys, size, dir, attrs);
- if (map == SWIOTLB_MAP_ERROR) {
- swiotlb_full(dev, size, dir, 1);
- return __phys_to_dma(dev, io_tlb_overflow_buffer);
+ if (!dma_capable(dev, dev_addr, size) ||
+ swiotlb_force == SWIOTLB_FORCE) {
+ trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
+ dev_addr = swiotlb_bounce_page(dev, &phys, size, dir, attrs);
}
- dev_addr = __phys_to_dma(dev, map);
+ if (!dev_is_dma_coherent(dev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ arch_sync_dma_for_device(dev, phys, size, dir);
- /* 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 __phys_to_dma(dev, io_tlb_overflow_buffer);
+ return dev_addr;
}
/*
@@ -842,14 +693,18 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
* After this call, reads by the cpu to the buffer are guaranteed to see
* whatever the device wrote there.
*/
-static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir,
- unsigned long attrs)
+void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
{
phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
BUG_ON(dir == DMA_NONE);
+ if (!dev_is_dma_coherent(hwdev) &&
+ (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
+ arch_sync_dma_for_cpu(hwdev, paddr, size, dir);
+
if (is_swiotlb_buffer(paddr)) {
swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs);
return;
@@ -867,13 +722,6 @@ static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
dma_mark_clean(phys_to_virt(paddr), size);
}
-void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
- size_t size, enum dma_data_direction dir,
- unsigned long attrs)
-{
- unmap_single(hwdev, dev_addr, size, dir, attrs);
-}
-
/*
* Make physical memory consistent for a single streaming mode DMA translation
* after a transfer.
@@ -893,15 +741,17 @@ swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
BUG_ON(dir == DMA_NONE);
- if (is_swiotlb_buffer(paddr)) {
+ if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_CPU)
+ arch_sync_dma_for_cpu(hwdev, paddr, size, dir);
+
+ if (is_swiotlb_buffer(paddr))
swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
- return;
- }
- if (dir != DMA_FROM_DEVICE)
- return;
+ if (!dev_is_dma_coherent(hwdev) && target == SYNC_FOR_DEVICE)
+ arch_sync_dma_for_device(hwdev, paddr, size, dir);
- dma_mark_clean(phys_to_virt(paddr), size);
+ if (!is_swiotlb_buffer(paddr) && dir == DMA_FROM_DEVICE)
+ dma_mark_clean(phys_to_virt(paddr), size);
}
void
@@ -925,48 +775,31 @@ swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
* 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 swiotlb_map_page are the
* same here.
*/
int
-swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
+swiotlb_map_sg_attrs(struct device *dev, 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 = phys_to_dma(hwdev, paddr);
-
- if (swiotlb_force == SWIOTLB_FORCE ||
- !dma_capable(hwdev, dev_addr, sg->length)) {
- phys_addr_t map = map_single(hwdev, sg_phys(sg),
- sg->length, dir, attrs);
- if (map == SWIOTLB_MAP_ERROR) {
- /* Don't panic here, we expect map_sg users
- to do proper error handling. */
- swiotlb_full(hwdev, sg->length, dir, 0);
- attrs |= DMA_ATTR_SKIP_CPU_SYNC;
- swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
- attrs);
- sg_dma_len(sgl) = 0;
- return 0;
- }
- sg->dma_address = __phys_to_dma(hwdev, map);
- } else
- sg->dma_address = dev_addr;
+ sg->dma_address = swiotlb_map_page(dev, sg_page(sg), sg->offset,
+ sg->length, dir, attrs);
+ if (sg->dma_address == DIRECT_MAPPING_ERROR)
+ goto out_error;
sg_dma_len(sg) = sg->length;
}
+
return nelems;
+
+out_error:
+ swiotlb_unmap_sg_attrs(dev, sgl, i, dir,
+ attrs | DMA_ATTR_SKIP_CPU_SYNC);
+ sg_dma_len(sgl) = 0;
+ return 0;
}
/*
@@ -984,7 +817,7 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
BUG_ON(dir == DMA_NONE);
for_each_sg(sgl, sg, nelems, i)
- unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir,
+ swiotlb_unmap_page(hwdev, sg->dma_address, sg_dma_len(sg), dir,
attrs);
}
@@ -1022,12 +855,6 @@ swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
}
-int
-swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
-{
- return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer));
-}
-
/*
* Return whether the given device DMA address mask can be supported
* properly. For example, if your device can only drive the low 24-bits
@@ -1040,39 +867,10 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask)
return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
}
-void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
- gfp_t gfp, unsigned long attrs)
-{
- void *vaddr;
-
- /* temporary workaround: */
- if (gfp & __GFP_NOWARN)
- attrs |= DMA_ATTR_NO_WARN;
-
- /*
- * Don't print a warning when the first allocation attempt fails.
- * swiotlb_alloc_coherent() will print a warning when the DMA memory
- * allocation ultimately failed.
- */
- gfp |= __GFP_NOWARN;
-
- vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
- if (!vaddr)
- vaddr = swiotlb_alloc_buffer(dev, size, dma_handle, attrs);
- return vaddr;
-}
-
-void swiotlb_free(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_addr, unsigned long attrs)
-{
- if (!swiotlb_free_buffer(dev, size, dma_addr))
- dma_direct_free(dev, size, vaddr, dma_addr, attrs);
-}
-
const struct dma_map_ops swiotlb_dma_ops = {
- .mapping_error = swiotlb_dma_mapping_error,
- .alloc = swiotlb_alloc,
- .free = swiotlb_free,
+ .mapping_error = dma_direct_mapping_error,
+ .alloc = dma_direct_alloc,
+ .free = dma_direct_free,
.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
.sync_single_for_device = swiotlb_sync_single_for_device,
.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,