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authorLinus Torvalds <torvalds@linux-foundation.org>2021-09-03 10:34:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-09-03 10:34:44 -0700
commit3de18c865f504ab59ed2588b1e11acd4bcb9ea09 (patch)
treea718decfd27fef64f8f922eb210c99228e890632 /kernel
parent14726903c835101cd8d0a703b609305094350d61 (diff)
parentf3c4b1341e8320e63f197a554fc5a25686a11d22 (diff)
Merge branch 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb updates from Konrad Rzeszutek Wilk: "A new feature called restricted DMA pools. It allows SWIOTLB to utilize per-device (or per-platform) allocated memory pools instead of using the global one. The first big user of this is ARM Confidential Computing where the memory for DMA operations can be set per platform" * 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits) swiotlb: use depends on for DMA_RESTRICTED_POOL of: restricted dma: Don't fail device probe on rmem init failure of: Move of_dma_set_restricted_buffer() into device.c powerpc/svm: Don't issue ultracalls if !mem_encrypt_active() s390/pv: fix the forcing of the swiotlb swiotlb: Free tbl memory in swiotlb_exit() swiotlb: Emit diagnostic in swiotlb_exit() swiotlb: Convert io_default_tlb_mem to static allocation of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS swiotlb: add overflow checks to swiotlb_bounce swiotlb: fix implicit debugfs declarations of: Add plumbing for restricted DMA pool dt-bindings: of: Add restricted DMA pool swiotlb: Add restricted DMA pool initialization swiotlb: Add restricted DMA alloc/free support swiotlb: Refactor swiotlb_tbl_unmap_single swiotlb: Move alloc_size to swiotlb_find_slots swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing swiotlb: Update is_swiotlb_active to add a struct device argument swiotlb: Update is_swiotlb_buffer to add a struct device argument ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/dma/Kconfig13
-rw-r--r--kernel/dma/direct.c57
-rw-r--r--kernel/dma/direct.h8
-rw-r--r--kernel/dma/swiotlb.c352
4 files changed, 319 insertions, 111 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 725cfd51762b..1b02179758cb 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -80,6 +80,19 @@ config SWIOTLB
bool
select NEED_DMA_MAP_STATE
+config DMA_RESTRICTED_POOL
+ bool "DMA Restricted Pool"
+ depends on OF && OF_RESERVED_MEM && SWIOTLB
+ help
+ This enables support for restricted DMA pools which provide a level of
+ DMA memory protection on systems with limited hardware protection
+ capabilities, such as those lacking an IOMMU.
+
+ For more information see
+ <Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt>
+ and <kernel/dma/swiotlb.c>.
+ If unsure, say "n".
+
#
# Should be selected if we can mmap non-coherent mappings to userspace.
# The only thing that is really required is a way to set an uncached bit
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 8dca4f97d12d..4c6c5e0635e3 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,6 +75,15 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
}
+static void __dma_direct_free_pages(struct device *dev, struct page *page,
+ size_t size)
+{
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+ swiotlb_free(dev, page, size))
+ return;
+ dma_free_contiguous(dev, page, size);
+}
+
static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp_t gfp)
{
@@ -86,6 +95,16 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
&phys_limit);
+ if (IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL) &&
+ is_swiotlb_for_alloc(dev)) {
+ page = swiotlb_alloc(dev, size);
+ if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+ __dma_direct_free_pages(dev, page, size);
+ return NULL;
+ }
+ return page;
+ }
+
page = dma_alloc_contiguous(dev, size, gfp);
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
dma_free_contiguous(dev, page, size);
@@ -142,7 +161,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
gfp |= __GFP_NOWARN;
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) {
page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
if (!page)
return NULL;
@@ -157,7 +176,8 @@ void *dma_direct_alloc(struct device *dev, size_t size,
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
!IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) &&
- !dev_is_dma_coherent(dev))
+ !dev_is_dma_coherent(dev) &&
+ !is_swiotlb_for_alloc(dev))
return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
if (IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) &&
@@ -167,11 +187,16 @@ void *dma_direct_alloc(struct device *dev, size_t size,
/*
* Remapping or decrypting memory may block. If either is required and
* we can't block, allocate the memory from the atomic pools.
+ * If restricted DMA (i.e., is_swiotlb_for_alloc) is required, one must
+ * set up another device coherent pool by shared-dma-pool and use
+ * dma_alloc_from_dev_coherent instead.
*/
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
!gfpflags_allow_blocking(gfp) &&
(force_dma_unencrypted(dev) ||
- (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+ (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+ !dev_is_dma_coherent(dev))) &&
+ !is_swiotlb_for_alloc(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
/* we always manually zero the memory once we are done */
@@ -242,7 +267,7 @@ out_encrypt_pages:
return NULL;
}
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -252,7 +277,7 @@ void dma_direct_free(struct device *dev, size_t size,
unsigned int page_order = get_order(size);
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
+ !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) {
/* cpu_addr is a struct page cookie, not a kernel address */
dma_free_contiguous(dev, cpu_addr, size);
return;
@@ -261,7 +286,8 @@ void dma_direct_free(struct device *dev, size_t size,
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
!IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) &&
- !dev_is_dma_coherent(dev)) {
+ !dev_is_dma_coherent(dev) &&
+ !is_swiotlb_for_alloc(dev)) {
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
return;
}
@@ -286,7 +312,7 @@ void dma_direct_free(struct device *dev, size_t size,
else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
arch_dma_clear_uncached(cpu_addr, size);
- dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
+ __dma_direct_free_pages(dev, dma_direct_to_page(dev, dma_addr), size);
}
struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
@@ -296,7 +322,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
void *ret;
if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
- force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
+ force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp) &&
+ !is_swiotlb_for_alloc(dev))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -323,7 +350,7 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
*dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
return page;
out_free_pages:
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
return NULL;
}
@@ -342,7 +369,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
if (force_dma_unencrypted(dev))
set_memory_encrypted((unsigned long)vaddr, 1 << page_order);
- dma_free_contiguous(dev, page, size);
+ __dma_direct_free_pages(dev, page, size);
}
#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
@@ -356,7 +383,7 @@ void dma_direct_sync_sg_for_device(struct device *dev,
for_each_sg(sgl, sg, nents, i) {
phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, sg->length,
dir);
@@ -382,7 +409,7 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu(paddr, sg->length, dir);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, sg->length,
dir);
@@ -510,8 +537,8 @@ int dma_direct_supported(struct device *dev, u64 mask)
size_t dma_direct_max_mapping_size(struct device *dev)
{
/* If SWIOTLB is active, use its maximum mapping size */
- if (is_swiotlb_active() &&
- (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+ if (is_swiotlb_active(dev) &&
+ (dma_addressing_limited(dev) || is_swiotlb_force_bounce(dev)))
return swiotlb_max_mapping_size(dev);
return SIZE_MAX;
}
@@ -519,7 +546,7 @@ size_t dma_direct_max_mapping_size(struct device *dev)
bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr)
{
return !dev_is_dma_coherent(dev) ||
- is_swiotlb_buffer(dma_to_phys(dev, dma_addr));
+ is_swiotlb_buffer(dev, dma_to_phys(dev, dma_addr));
}
/**
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 50afc05b6f1d..4632b0f4f72e 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -56,7 +56,7 @@ static inline void dma_direct_sync_single_for_device(struct device *dev,
{
phys_addr_t paddr = dma_to_phys(dev, addr);
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_device(dev, paddr, size, dir);
if (!dev_is_dma_coherent(dev))
@@ -73,7 +73,7 @@ static inline void dma_direct_sync_single_for_cpu(struct device *dev,
arch_sync_dma_for_cpu_all();
}
- if (unlikely(is_swiotlb_buffer(paddr)))
+ if (unlikely(is_swiotlb_buffer(dev, paddr)))
swiotlb_sync_single_for_cpu(dev, paddr, size, dir);
if (dir == DMA_FROM_DEVICE)
@@ -87,7 +87,7 @@ static inline dma_addr_t dma_direct_map_page(struct device *dev,
phys_addr_t phys = page_to_phys(page) + offset;
dma_addr_t dma_addr = phys_to_dma(dev, phys);
- if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+ if (is_swiotlb_force_bounce(dev))
return swiotlb_map(dev, phys, size, dir, attrs);
if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
@@ -113,7 +113,7 @@ static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
dma_direct_sync_single_for_cpu(dev, addr, size, dir);
- if (unlikely(is_swiotlb_buffer(phys)))
+ if (unlikely(is_swiotlb_buffer(dev, phys)))
swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs);
}
#endif /* _KERNEL_DMA_DIRECT_H */
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index e50df8d8f87e..87c40517e822 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -39,6 +39,13 @@
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#endif
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/slab.h>
+#endif
#include <asm/io.h>
#include <asm/dma.h>
@@ -63,7 +70,7 @@
enum swiotlb_force swiotlb_force;
-struct io_tlb_mem *io_tlb_default_mem;
+struct io_tlb_mem io_tlb_default_mem;
/*
* Max segment that we can provide which (if pages are contingous) will
@@ -94,7 +101,7 @@ early_param("swiotlb", setup_io_tlb_npages);
unsigned int swiotlb_max_segment(void)
{
- return io_tlb_default_mem ? max_segment : 0;
+ return io_tlb_default_mem.nslabs ? max_segment : 0;
}
EXPORT_SYMBOL_GPL(swiotlb_max_segment);
@@ -127,9 +134,9 @@ void __init swiotlb_adjust_size(unsigned long size)
void swiotlb_print_info(void)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
- if (!mem) {
+ if (!mem->nslabs) {
pr_warn("No low mem\n");
return;
}
@@ -156,11 +163,11 @@ static inline unsigned long nr_slots(u64 val)
*/
void __init swiotlb_update_mem_attributes(void)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
void *vaddr;
unsigned long bytes;
- if (!mem || mem->late_alloc)
+ if (!mem->nslabs || mem->late_alloc)
return;
vaddr = phys_to_virt(mem->start);
bytes = PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT);
@@ -168,36 +175,50 @@ void __init swiotlb_update_mem_attributes(void)
memset(vaddr, 0, bytes);
}
-int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
+ unsigned long nslabs, bool late_alloc)
{
+ void *vaddr = phys_to_virt(start);
unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
- struct io_tlb_mem *mem;
- size_t alloc_size;
-
- if (swiotlb_force == SWIOTLB_NO_FORCE)
- return 0;
-
- /* protect against double initialization */
- if (WARN_ON_ONCE(io_tlb_default_mem))
- return -ENOMEM;
- alloc_size = PAGE_ALIGN(struct_size(mem, slots, nslabs));
- mem = memblock_alloc(alloc_size, PAGE_SIZE);
- if (!mem)
- panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
- __func__, alloc_size, PAGE_SIZE);
mem->nslabs = nslabs;
- mem->start = __pa(tlb);
+ mem->start = start;
mem->end = mem->start + bytes;
mem->index = 0;
+ mem->late_alloc = late_alloc;
+
+ if (swiotlb_force == SWIOTLB_FORCE)
+ mem->force_bounce = true;
+
spin_lock_init(&mem->lock);
for (i = 0; i < mem->nslabs; i++) {
mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
mem->slots[i].alloc_size = 0;
}
+ memset(vaddr, 0, bytes);
+}
+
+int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
+{
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
+ size_t alloc_size;
+
+ if (swiotlb_force == SWIOTLB_NO_FORCE)
+ return 0;
+
+ /* protect against double initialization */
+ if (WARN_ON_ONCE(mem->nslabs))
+ return -ENOMEM;
+
+ alloc_size = PAGE_ALIGN(array_size(sizeof(*mem->slots), nslabs));
+ mem->slots = memblock_alloc(alloc_size, PAGE_SIZE);
+ if (!mem->slots)
+ panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
+ __func__, alloc_size, PAGE_SIZE);
+
+ swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, false);
- io_tlb_default_mem = mem;
if (verbose)
swiotlb_print_info();
swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);
@@ -282,37 +303,24 @@ swiotlb_late_init_with_default_size(size_t default_size)
int
swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
- unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
- struct io_tlb_mem *mem;
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
+ unsigned long bytes = nslabs << IO_TLB_SHIFT;
if (swiotlb_force == SWIOTLB_NO_FORCE)
return 0;
/* protect against double initialization */
- if (WARN_ON_ONCE(io_tlb_default_mem))
+ if (WARN_ON_ONCE(mem->nslabs))
return -ENOMEM;
- mem = (void *)__get_free_pages(GFP_KERNEL,
- get_order(struct_size(mem, slots, nslabs)));
- if (!mem)
+ mem->slots = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(array_size(sizeof(*mem->slots), nslabs)));
+ if (!mem->slots)
return -ENOMEM;
- mem->nslabs = nslabs;
- mem->start = virt_to_phys(tlb);
- mem->end = mem->start + bytes;
- mem->index = 0;
- mem->late_alloc = 1;
- spin_lock_init(&mem->lock);
- for (i = 0; i < mem->nslabs; i++) {
- mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
- mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
- mem->slots[i].alloc_size = 0;
- }
-
set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
- memset(tlb, 0, bytes);
+ swiotlb_init_io_tlb_mem(mem, virt_to_phys(tlb), nslabs, true);
- io_tlb_default_mem = mem;
swiotlb_print_info();
swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);
return 0;
@@ -320,18 +328,28 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
void __init swiotlb_exit(void)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
- size_t size;
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
+ unsigned long tbl_vaddr;
+ size_t tbl_size, slots_size;
- if (!mem)
+ if (!mem->nslabs)
return;
- size = struct_size(mem, slots, mem->nslabs);
- if (mem->late_alloc)
- free_pages((unsigned long)mem, get_order(size));
- else
- memblock_free_late(__pa(mem), PAGE_ALIGN(size));
- io_tlb_default_mem = NULL;
+ pr_info("tearing down default memory pool\n");
+ tbl_vaddr = (unsigned long)phys_to_virt(mem->start);
+ tbl_size = PAGE_ALIGN(mem->end - mem->start);
+ slots_size = PAGE_ALIGN(array_size(sizeof(*mem->slots), mem->nslabs));
+
+ set_memory_encrypted(tbl_vaddr, tbl_size >> PAGE_SHIFT);
+ if (mem->late_alloc) {
+ free_pages(tbl_vaddr, get_order(tbl_size));
+ free_pages((unsigned long)mem->slots, get_order(slots_size));
+ } else {
+ memblock_free_late(mem->start, tbl_size);
+ memblock_free_late(__pa(mem->slots), slots_size);
+ }
+
+ memset(mem, 0, sizeof(*mem));
}
/*
@@ -348,19 +366,33 @@ static unsigned int swiotlb_align_offset(struct device *dev, u64 addr)
static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size,
enum dma_data_direction dir)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT;
phys_addr_t orig_addr = mem->slots[index].orig_addr;
size_t alloc_size = mem->slots[index].alloc_size;
unsigned long pfn = PFN_DOWN(orig_addr);
unsigned char *vaddr = phys_to_virt(tlb_addr);
- unsigned int tlb_offset;
+ unsigned int tlb_offset, orig_addr_offset;
if (orig_addr == INVALID_PHYS_ADDR)
return;
- tlb_offset = (tlb_addr & (IO_TLB_SIZE - 1)) -
- swiotlb_align_offset(dev, orig_addr);
+ tlb_offset = tlb_addr & (IO_TLB_SIZE - 1);
+ orig_addr_offset = swiotlb_align_offset(dev, orig_addr);
+ if (tlb_offset < orig_addr_offset) {
+ dev_WARN_ONCE(dev, 1,
+ "Access before mapping start detected. orig offset %u, requested offset %u.\n",
+ orig_addr_offset, tlb_offset);
+ return;
+ }
+
+ tlb_offset -= orig_addr_offset;
+ if (tlb_offset > alloc_size) {
+ dev_WARN_ONCE(dev, 1,
+ "Buffer overflow detected. Allocation size: %zu. Mapping size: %zu+%u.\n",
+ alloc_size, size, tlb_offset);
+ return;
+ }
orig_addr += tlb_offset;
alloc_size -= tlb_offset;
@@ -426,10 +458,10 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
* Find a suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
*/
-static int find_slots(struct device *dev, phys_addr_t orig_addr,
- size_t alloc_size)
+static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
+ size_t alloc_size)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
dma_addr_t tbl_dma_addr =
phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;
@@ -438,6 +470,7 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
unsigned int nslots = nr_slots(alloc_size), stride;
unsigned int index, wrap, count = 0, i;
+ unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned long flags;
BUG_ON(!nslots);
@@ -457,8 +490,9 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr,
index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
do {
- if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
- (orig_addr & iotlb_align_mask)) {
+ if (orig_addr &&
+ (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
+ (orig_addr & iotlb_align_mask)) {
index = wrap_index(mem, index + 1);
continue;
}
@@ -482,8 +516,11 @@ not_found:
return -1;
found:
- for (i = index; i < index + nslots; i++)
+ for (i = index; i < index + nslots; i++) {
mem->slots[i].list = 0;
+ mem->slots[i].alloc_size =
+ alloc_size - (offset + ((i - index) << IO_TLB_SHIFT));
+ }
for (i = index - 1;
io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
mem->slots[i].list; i--)
@@ -506,7 +543,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
size_t mapping_size, size_t alloc_size,
enum dma_data_direction dir, unsigned long attrs)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned int i;
int index;
@@ -524,7 +561,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return (phys_addr_t)DMA_MAPPING_ERROR;
}
- index = find_slots(dev, orig_addr, alloc_size + offset);
+ index = swiotlb_find_slots(dev, orig_addr, alloc_size + offset);
if (index == -1) {
if (!(attrs & DMA_ATTR_NO_WARN))
dev_warn_ratelimited(dev,
@@ -538,11 +575,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
* This is needed when we sync the memory. Then we sync the buffer if
* needed.
*/
- for (i = 0; i < nr_slots(alloc_size + offset); i++) {
+ for (i = 0; i < nr_slots(alloc_size + offset); i++)
mem->slots[index + i].orig_addr = slot_addr(orig_addr, i);
- mem->slots[index + i].alloc_size =
- alloc_size - (i << IO_TLB_SHIFT);
- }
tlb_addr = slot_addr(mem->start, index) + offset;
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
@@ -550,28 +584,16 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
return tlb_addr;
}
-/*
- * 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,
- size_t mapping_size, enum dma_data_direction dir,
- unsigned long attrs)
+static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long flags;
- unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
+ unsigned int offset = swiotlb_align_offset(dev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
int nslots = nr_slots(mem->slots[index].alloc_size + offset);
int count, i;
/*
- * First, sync the memory before unmapping the entry
- */
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
- (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
- swiotlb_bounce(hwdev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
-
- /*
* Return the buffer to the free list by setting the corresponding
* entries to indicate the number of contiguous entries available.
* While returning the entries to the free list, we merge the entries
@@ -605,6 +627,23 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
spin_unlock_irqrestore(&mem->lock, flags);
}
+/*
+ * tlb_addr is the physical address of the bounce buffer to unmap.
+ */
+void swiotlb_tbl_unmap_single(struct device *dev, phys_addr_t tlb_addr,
+ size_t mapping_size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ /*
+ * First, sync the memory before unmapping the entry
+ */
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
+ (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
+ swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_FROM_DEVICE);
+
+ swiotlb_release_slots(dev, tlb_addr);
+}
+
void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
size_t size, enum dma_data_direction dir)
{
@@ -662,26 +701,155 @@ size_t swiotlb_max_mapping_size(struct device *dev)
return ((size_t)IO_TLB_SIZE) * IO_TLB_SEGSIZE;
}
-bool is_swiotlb_active(void)
+bool is_swiotlb_active(struct device *dev)
{
- return io_tlb_default_mem != NULL;
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+
+ return mem && mem->nslabs;
}
EXPORT_SYMBOL_GPL(is_swiotlb_active);
#ifdef CONFIG_DEBUG_FS
+static struct dentry *debugfs_dir;
-static int __init swiotlb_create_debugfs(void)
+static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
-
- if (!mem)
- return 0;
- mem->debugfs = debugfs_create_dir("swiotlb", NULL);
debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);
debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);
+}
+
+static int __init swiotlb_create_default_debugfs(void)
+{
+ struct io_tlb_mem *mem = &io_tlb_default_mem;
+
+ debugfs_dir = debugfs_create_dir("swiotlb", NULL);
+ if (mem->nslabs) {
+ mem->debugfs = debugfs_dir;
+ swiotlb_create_debugfs_files(mem);
+ }
return 0;
}
-late_initcall(swiotlb_create_debugfs);
+late_initcall(swiotlb_create_default_debugfs);
+
+#endif
+#ifdef CONFIG_DMA_RESTRICTED_POOL
+
+#ifdef CONFIG_DEBUG_FS
+static void rmem_swiotlb_debugfs_init(struct reserved_mem *rmem)
+{
+ struct io_tlb_mem *mem = rmem->priv;
+
+ mem->debugfs = debugfs_create_dir(rmem->name, debugfs_dir);
+ swiotlb_create_debugfs_files(mem);
+}
+#else
+static void rmem_swiotlb_debugfs_init(struct reserved_mem *rmem)
+{
+}
#endif
+
+struct page *swiotlb_alloc(struct device *dev, size_t size)
+{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+ phys_addr_t tlb_addr;
+ int index;
+
+ if (!mem)
+ return NULL;
+
+ index = swiotlb_find_slots(dev, 0, size);
+ if (index == -1)
+ return NULL;
+
+ tlb_addr = slot_addr(mem->start, index);
+
+ return pfn_to_page(PFN_DOWN(tlb_addr));
+}
+
+bool swiotlb_free(struct device *dev, struct page *page, size_t size)
+{
+ phys_addr_t tlb_addr = page_to_phys(page);
+
+ if (!is_swiotlb_buffer(dev, tlb_addr))
+ return false;
+
+ swiotlb_release_slots(dev, tlb_addr);
+
+ return true;
+}
+
+static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ struct io_tlb_mem *mem = rmem->priv;
+ unsigned long nslabs = rmem->size >> IO_TLB_SHIFT;
+
+ /*
+ * Since multiple devices can share the same pool, the private data,
+ * io_tlb_mem struct, will be initialized by the first device attached
+ * to it.
+ */
+ if (!mem) {
+ mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+ if (!mem)
+ return -ENOMEM;
+
+ mem->slots = kzalloc(array_size(sizeof(*mem->slots), nslabs),
+ GFP_KERNEL);
+ if (!mem->slots) {
+ kfree(mem);
+ return -ENOMEM;
+ }
+
+ set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
+ rmem->size >> PAGE_SHIFT);
+ swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, false);
+ mem->force_bounce = true;
+ mem->for_alloc = true;
+
+ rmem->priv = mem;
+
+ rmem_swiotlb_debugfs_init(rmem);
+ }
+
+ dev->dma_io_tlb_mem = mem;
+
+ return 0;
+}
+
+static void rmem_swiotlb_device_release(struct reserved_mem *rmem,
+ struct device *dev)
+{
+ dev->dma_io_tlb_mem = &io_tlb_default_mem;
+}
+
+static const struct reserved_mem_ops rmem_swiotlb_ops = {
+ .device_init = rmem_swiotlb_device_init,
+ .device_release = rmem_swiotlb_device_release,
+};
+
+static int __init rmem_swiotlb_setup(struct reserved_mem *rmem)
+{
+ unsigned long node = rmem->fdt_node;
+
+ if (of_get_flat_dt_prop(node, "reusable", NULL) ||
+ of_get_flat_dt_prop(node, "linux,cma-default", NULL) ||
+ of_get_flat_dt_prop(node, "linux,dma-default", NULL) ||
+ of_get_flat_dt_prop(node, "no-map", NULL))
+ return -EINVAL;
+
+ if (PageHighMem(pfn_to_page(PHYS_PFN(rmem->base)))) {
+ pr_err("Restricted DMA pool must be accessible within the linear mapping.");
+ return -EINVAL;
+ }
+
+ rmem->ops = &rmem_swiotlb_ops;
+ pr_info("Reserved memory: created restricted DMA pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+ return 0;
+}
+
+RESERVEDMEM_OF_DECLARE(dma, "restricted-dma-pool", rmem_swiotlb_setup);
+#endif /* CONFIG_DMA_RESTRICTED_POOL */