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authorLinus Torvalds <torvalds@linux-foundation.org>2021-02-24 20:54:24 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-02-24 20:54:24 +0300
commita4dec04c7ff4307973ba502ce7b27330d9fe04b7 (patch)
treefd112ec6ce9ab4a3a0c7c3e2eb67b2c9e8f6fd29
parentb817c931233b24129ac8d2c858669ee656a473dd (diff)
parent81d88ce55092edf1a1f928efb373f289c6b90efd (diff)
downloadlinux-a4dec04c7ff4307973ba502ce7b27330d9fe04b7.tar.xz
Merge tag 'dma-mapping-5.12' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig: - add support to emulate processing delays in the DMA API benchmark selftest (Barry Song) - remove support for non-contiguous noncoherent allocations, which aren't used and will be replaced by a different API * tag 'dma-mapping-5.12' of git://git.infradead.org/users/hch/dma-mapping: dma-mapping: remove the {alloc,free}_noncoherent methods dma-mapping: benchmark: pretend DMA is transmitting
-rw-r--r--Documentation/core-api/dma-api.rst64
-rw-r--r--drivers/iommu/dma-iommu.c30
-rw-r--r--include/linux/dma-map-ops.h5
-rw-r--r--include/linux/dma-mapping.h17
-rw-r--r--kernel/dma/map_benchmark.c12
-rw-r--r--kernel/dma/mapping.c40
-rw-r--r--tools/testing/selftests/dma/dma_map_benchmark.c21
7 files changed, 64 insertions, 125 deletions
diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst
index 75cb757bbff0..e6d23f117308 100644
--- a/Documentation/core-api/dma-api.rst
+++ b/Documentation/core-api/dma-api.rst
@@ -528,16 +528,14 @@ an I/O device, you should not be using this part of the API.
::
- void *
- dma_alloc_noncoherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, enum dma_data_direction dir,
- gfp_t gfp)
+ struct page *
+ dma_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle,
+ enum dma_data_direction dir, gfp_t gfp)
-This routine allocates a region of <size> bytes of consistent memory. It
-returns a pointer to the allocated region (in the processor's virtual address
-space) or NULL if the allocation failed. The returned memory may or may not
-be in the kernel direct mapping. Drivers must not call virt_to_page on
-the returned memory region.
+This routine allocates a region of <size> bytes of non-coherent memory. It
+returns a pointer to first struct page for the region, or NULL if the
+allocation failed. The resulting struct page can be used for everything a
+struct page is suitable for.
It also returns a <dma_handle> which may be cast to an unsigned integer the
same width as the bus and given to the device as the DMA address base of
@@ -558,51 +556,33 @@ reused.
::
void
- dma_free_noncoherent(struct device *dev, size_t size, void *cpu_addr,
+ dma_free_pages(struct device *dev, size_t size, struct page *page,
dma_addr_t dma_handle, enum dma_data_direction dir)
-Free a region of memory previously allocated using dma_alloc_noncoherent().
-dev, size and dma_handle and dir must all be the same as those passed into
-dma_alloc_noncoherent(). cpu_addr must be the virtual address returned by
-dma_alloc_noncoherent().
+Free a region of memory previously allocated using dma_alloc_pages().
+dev, size, dma_handle and dir must all be the same as those passed into
+dma_alloc_pages(). page must be the pointer returned by dma_alloc_pages().
::
- struct page *
- dma_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle,
- enum dma_data_direction dir, gfp_t gfp)
-
-This routine allocates a region of <size> bytes of non-coherent memory. It
-returns a pointer to first struct page for the region, or NULL if the
-allocation failed. The resulting struct page can be used for everything a
-struct page is suitable for.
-
-It also returns a <dma_handle> which may be cast to an unsigned integer the
-same width as the bus and given to the device as the DMA address base of
-the region.
-
-The dir parameter specified if data is read and/or written by the device,
-see dma_map_single() for details.
-
-The gfp parameter allows the caller to specify the ``GFP_`` flags (see
-kmalloc()) for the allocation, but rejects flags used to specify a memory
-zone such as GFP_DMA or GFP_HIGHMEM.
+ void *
+ dma_alloc_noncoherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, enum dma_data_direction dir,
+ gfp_t gfp)
-Before giving the memory to the device, dma_sync_single_for_device() needs
-to be called, and before reading memory written by the device,
-dma_sync_single_for_cpu(), just like for streaming DMA mappings that are
-reused.
+This routine is a convenient wrapper around dma_alloc_pages that returns the
+kernel virtual address for the allocated memory instead of the page structure.
::
void
- dma_free_pages(struct device *dev, size_t size, struct page *page,
+ dma_free_noncoherent(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_handle, enum dma_data_direction dir)
-Free a region of memory previously allocated using dma_alloc_pages().
-dev, size and dma_handle and dir must all be the same as those passed into
-dma_alloc_noncoherent(). page must be the pointer returned by
-dma_alloc_pages().
+Free a region of memory previously allocated using dma_alloc_noncoherent().
+dev, size, dma_handle and dir must all be the same as those passed into
+dma_alloc_noncoherent(). cpu_addr must be the virtual address returned by
+dma_alloc_noncoherent().
::
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index f659395e7959..9ab6ee22c110 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1187,34 +1187,6 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,
return cpu_addr;
}
-#ifdef CONFIG_DMA_REMAP
-static void *iommu_dma_alloc_noncoherent(struct device *dev, size_t size,
- dma_addr_t *handle, enum dma_data_direction dir, gfp_t gfp)
-{
- if (!gfpflags_allow_blocking(gfp)) {
- struct page *page;
-
- page = dma_common_alloc_pages(dev, size, handle, dir, gfp);
- if (!page)
- return NULL;
- return page_address(page);
- }
-
- return iommu_dma_alloc_remap(dev, size, handle, gfp | __GFP_ZERO,
- PAGE_KERNEL, 0);
-}
-
-static void iommu_dma_free_noncoherent(struct device *dev, size_t size,
- void *cpu_addr, dma_addr_t handle, enum dma_data_direction dir)
-{
- __iommu_dma_unmap(dev, handle, size);
- __iommu_dma_free(dev, size, cpu_addr);
-}
-#else
-#define iommu_dma_alloc_noncoherent NULL
-#define iommu_dma_free_noncoherent NULL
-#endif /* CONFIG_DMA_REMAP */
-
static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
unsigned long attrs)
@@ -1285,8 +1257,6 @@ static const struct dma_map_ops iommu_dma_ops = {
.free = iommu_dma_free,
.alloc_pages = dma_common_alloc_pages,
.free_pages = dma_common_free_pages,
- .alloc_noncoherent = iommu_dma_alloc_noncoherent,
- .free_noncoherent = iommu_dma_free_noncoherent,
.mmap = iommu_dma_mmap,
.get_sgtable = iommu_dma_get_sgtable,
.map_page = iommu_dma_map_page,
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 1e98b8c1e055..51872e736e7b 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -22,11 +22,6 @@ struct dma_map_ops {
gfp_t gfp);
void (*free_pages)(struct device *dev, size_t size, struct page *vaddr,
dma_addr_t dma_handle, enum dma_data_direction dir);
- void *(*alloc_noncoherent)(struct device *dev, size_t size,
- dma_addr_t *dma_handle, enum dma_data_direction dir,
- gfp_t gfp);
- void (*free_noncoherent)(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle, enum dma_data_direction dir);
int (*mmap)(struct device *, struct vm_area_struct *,
void *, dma_addr_t, size_t, unsigned long attrs);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 2e49996a8f39..fbfa3f5abd94 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -263,10 +263,19 @@ struct page *dma_alloc_pages(struct device *dev, size_t size,
dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
void dma_free_pages(struct device *dev, size_t size, struct page *page,
dma_addr_t dma_handle, enum dma_data_direction dir);
-void *dma_alloc_noncoherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
-void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle, enum dma_data_direction dir);
+
+static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
+{
+ struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
+ return page ? page_address(page) : NULL;
+}
+
+static inline void dma_free_noncoherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
+{
+ dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
+}
static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
size_t size, enum dma_data_direction dir, unsigned long attrs)
diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index da95df381483..e0e64f8b0739 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -21,6 +21,7 @@
#define DMA_MAP_BENCHMARK _IOWR('d', 1, struct map_benchmark)
#define DMA_MAP_MAX_THREADS 1024
#define DMA_MAP_MAX_SECONDS 300
+#define DMA_MAP_MAX_TRANS_DELAY (10 * NSEC_PER_MSEC)
#define DMA_MAP_BIDIRECTIONAL 0
#define DMA_MAP_TO_DEVICE 1
@@ -36,7 +37,8 @@ struct map_benchmark {
__s32 node; /* which numa node this benchmark will run on */
__u32 dma_bits; /* DMA addressing capability */
__u32 dma_dir; /* DMA data direction */
- __u8 expansion[84]; /* For future use */
+ __u32 dma_trans_ns; /* time for DMA transmission in ns */
+ __u8 expansion[80]; /* For future use */
};
struct map_benchmark_data {
@@ -87,6 +89,9 @@ static int map_benchmark_thread(void *data)
map_etime = ktime_get();
map_delta = ktime_sub(map_etime, map_stime);
+ /* Pretend DMA is transmitting */
+ ndelay(map->bparam.dma_trans_ns);
+
unmap_stime = ktime_get();
dma_unmap_single(map->dev, dma_addr, PAGE_SIZE, map->dir);
unmap_etime = ktime_get();
@@ -218,6 +223,11 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
return -EINVAL;
}
+ if (map->bparam.dma_trans_ns > DMA_MAP_MAX_TRANS_DELAY) {
+ pr_err("invalid transmission delay\n");
+ return -EINVAL;
+ }
+
if (map->bparam.node != NUMA_NO_NODE &&
!node_possible(map->bparam.node)) {
pr_err("invalid numa node\n");
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 84de6b1c5fab..b6a633679933 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -517,46 +517,6 @@ void dma_free_pages(struct device *dev, size_t size, struct page *page,
}
EXPORT_SYMBOL_GPL(dma_free_pages);
-void *dma_alloc_noncoherent(struct device *dev, size_t size,
- dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
-{
- const struct dma_map_ops *ops = get_dma_ops(dev);
- void *vaddr;
-
- if (!ops || !ops->alloc_noncoherent) {
- struct page *page;
-
- page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
- if (!page)
- return NULL;
- return page_address(page);
- }
-
- size = PAGE_ALIGN(size);
- vaddr = ops->alloc_noncoherent(dev, size, dma_handle, dir, gfp);
- if (vaddr)
- debug_dma_map_page(dev, virt_to_page(vaddr), 0, size, dir,
- *dma_handle);
- return vaddr;
-}
-EXPORT_SYMBOL_GPL(dma_alloc_noncoherent);
-
-void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle, enum dma_data_direction dir)
-{
- const struct dma_map_ops *ops = get_dma_ops(dev);
-
- if (!ops || !ops->free_noncoherent) {
- dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
- return;
- }
-
- size = PAGE_ALIGN(size);
- debug_dma_unmap_page(dev, dma_handle, size, dir);
- ops->free_noncoherent(dev, size, vaddr, dma_handle, dir);
-}
-EXPORT_SYMBOL_GPL(dma_free_noncoherent);
-
int dma_supported(struct device *dev, u64 mask)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
diff --git a/tools/testing/selftests/dma/dma_map_benchmark.c b/tools/testing/selftests/dma/dma_map_benchmark.c
index 537d65968c48..fb23ce9617ea 100644
--- a/tools/testing/selftests/dma/dma_map_benchmark.c
+++ b/tools/testing/selftests/dma/dma_map_benchmark.c
@@ -12,9 +12,12 @@
#include <sys/mman.h>
#include <linux/types.h>
+#define NSEC_PER_MSEC 1000000L
+
#define DMA_MAP_BENCHMARK _IOWR('d', 1, struct map_benchmark)
#define DMA_MAP_MAX_THREADS 1024
#define DMA_MAP_MAX_SECONDS 300
+#define DMA_MAP_MAX_TRANS_DELAY (10 * NSEC_PER_MSEC)
#define DMA_MAP_BIDIRECTIONAL 0
#define DMA_MAP_TO_DEVICE 1
@@ -36,7 +39,8 @@ struct map_benchmark {
__s32 node; /* which numa node this benchmark will run on */
__u32 dma_bits; /* DMA addressing capability */
__u32 dma_dir; /* DMA data direction */
- __u8 expansion[84]; /* For future use */
+ __u32 dma_trans_ns; /* time for DMA transmission in ns */
+ __u8 expansion[80]; /* For future use */
};
int main(int argc, char **argv)
@@ -46,12 +50,12 @@ int main(int argc, char **argv)
/* default single thread, run 20 seconds on NUMA_NO_NODE */
int threads = 1, seconds = 20, node = -1;
/* default dma mask 32bit, bidirectional DMA */
- int bits = 32, dir = DMA_MAP_BIDIRECTIONAL;
+ int bits = 32, xdelay = 0, dir = DMA_MAP_BIDIRECTIONAL;
int cmd = DMA_MAP_BENCHMARK;
char *p;
- while ((opt = getopt(argc, argv, "t:s:n:b:d:")) != -1) {
+ while ((opt = getopt(argc, argv, "t:s:n:b:d:x:")) != -1) {
switch (opt) {
case 't':
threads = atoi(optarg);
@@ -68,6 +72,9 @@ int main(int argc, char **argv)
case 'd':
dir = atoi(optarg);
break;
+ case 'x':
+ xdelay = atoi(optarg);
+ break;
default:
return -1;
}
@@ -85,6 +92,12 @@ int main(int argc, char **argv)
exit(1);
}
+ if (xdelay < 0 || xdelay > DMA_MAP_MAX_TRANS_DELAY) {
+ fprintf(stderr, "invalid transmit delay, must be in 0-%ld\n",
+ DMA_MAP_MAX_TRANS_DELAY);
+ exit(1);
+ }
+
/* suppose the mininum DMA zone is 1MB in the world */
if (bits < 20 || bits > 64) {
fprintf(stderr, "invalid dma mask bit, must be in 20-64\n");
@@ -109,6 +122,8 @@ int main(int argc, char **argv)
map.node = node;
map.dma_bits = bits;
map.dma_dir = dir;
+ map.dma_trans_ns = xdelay;
+
if (ioctl(fd, cmd, &map)) {
perror("ioctl");
exit(1);