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authorLinus Torvalds <torvalds@linux-foundation.org>2019-03-10 11:54:48 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-03-10 11:54:48 -0700
commitb7a7d1c1ec688104fdc922568c26395a756f616d (patch)
tree8059a401de91431615737b088f3da20d4567683e /kernel
parent065b6c4c913d3986c2118acb7e7fb364ce4fb625 (diff)
parent9eb9e96e97b3381e94cba81d93f4a390c26ca6cb (diff)
downloadlinux-b7a7d1c1ec688104fdc922568c26395a756f616d.tar.bz2
Merge tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mapping
Pull DMA mapping updates from Christoph Hellwig: - add debugfs support for dumping dma-debug information (Corentin Labbe) - Kconfig cleanups (Andy Shevchenko and me) - debugfs cleanups (Greg Kroah-Hartman) - improve dma_map_resource and use it in the media code - arch_setup_dma_ops / arch_teardown_dma_ops cleanups - various small cleanups and improvements for the per-device coherent allocator - make the DMA mask an upper bound and don't fail "too large" dma mask in the remaning two architectures - this will allow big driver cleanups in the following merge windows * tag 'dma-mapping-5.1' of git://git.infradead.org/users/hch/dma-mapping: (21 commits) Documentation/DMA-API-HOWTO: update dma_mask sections sparc64/pci_sun4v: allow large DMA masks sparc64/iommu: allow large DMA masks sparc64: refactor the ali DMA quirk ccio: allow large DMA masks dma-mapping: remove the DMA_MEMORY_EXCLUSIVE flag dma-mapping: remove dma_mark_declared_memory_occupied dma-mapping: move CONFIG_DMA_CMA to kernel/dma/Kconfig dma-mapping: improve selection of dma_declare_coherent availability dma-mapping: remove an incorrect __iommem annotation of: select OF_RESERVED_MEM automatically device.h: dma_mem is only needed for HAVE_GENERIC_DMA_COHERENT mfd/sm501: depend on HAS_DMA dma-mapping: add a kconfig symbol for arch_teardown_dma_ops availability dma-mapping: add a kconfig symbol for arch_setup_dma_ops availability dma-mapping: move debug configuration options to kernel/dma dma-debug: add dumping facility via debugfs dma: debug: no need to check return value of debugfs_create functions videobuf2: replace a layering violation with dma_map_resource dma-mapping: don't BUG when calling dma_map_resource on RAM ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/dma/Kconfig121
-rw-r--r--kernel/dma/Makefile2
-rw-r--r--kernel/dma/coherent.c50
-rw-r--r--kernel/dma/debug.c108
-rw-r--r--kernel/dma/direct.c14
5 files changed, 179 insertions, 116 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 0711d18645de..a06ba3013b3b 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -19,7 +19,13 @@ config ARCH_HAS_DMA_COHERENCE_H
config ARCH_HAS_DMA_SET_MASK
bool
-config HAVE_GENERIC_DMA_COHERENT
+config DMA_DECLARE_COHERENT
+ bool
+
+config ARCH_HAS_SETUP_DMA_OPS
+ bool
+
+config ARCH_HAS_TEARDOWN_DMA_OPS
bool
config ARCH_HAS_SYNC_DMA_FOR_DEVICE
@@ -56,3 +62,116 @@ config DMA_REMAP
config DMA_DIRECT_REMAP
bool
select DMA_REMAP
+
+config DMA_CMA
+ bool "DMA Contiguous Memory Allocator"
+ depends on HAVE_DMA_CONTIGUOUS && CMA
+ help
+ This enables the Contiguous Memory Allocator which allows drivers
+ to allocate big physically-contiguous blocks of memory for use with
+ hardware components that do not support I/O map nor scatter-gather.
+
+ You can disable CMA by specifying "cma=0" on the kernel's command
+ line.
+
+ For more information see <include/linux/dma-contiguous.h>.
+ If unsure, say "n".
+
+if DMA_CMA
+comment "Default contiguous memory area size:"
+
+config CMA_SIZE_MBYTES
+ int "Size in Mega Bytes"
+ depends on !CMA_SIZE_SEL_PERCENTAGE
+ default 0 if X86
+ default 16
+ help
+ Defines the size (in MiB) of the default memory area for Contiguous
+ Memory Allocator. If the size of 0 is selected, CMA is disabled by
+ default, but it can be enabled by passing cma=size[MG] to the kernel.
+
+
+config CMA_SIZE_PERCENTAGE
+ int "Percentage of total memory"
+ depends on !CMA_SIZE_SEL_MBYTES
+ default 0 if X86
+ default 10
+ help
+ Defines the size of the default memory area for Contiguous Memory
+ Allocator as a percentage of the total memory in the system.
+ If 0 percent is selected, CMA is disabled by default, but it can be
+ enabled by passing cma=size[MG] to the kernel.
+
+choice
+ prompt "Selected region size"
+ default CMA_SIZE_SEL_MBYTES
+
+config CMA_SIZE_SEL_MBYTES
+ bool "Use mega bytes value only"
+
+config CMA_SIZE_SEL_PERCENTAGE
+ bool "Use percentage value only"
+
+config CMA_SIZE_SEL_MIN
+ bool "Use lower value (minimum)"
+
+config CMA_SIZE_SEL_MAX
+ bool "Use higher value (maximum)"
+
+endchoice
+
+config CMA_ALIGNMENT
+ int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
+ range 4 12
+ default 8
+ help
+ DMA mapping framework by default aligns all buffers to the smallest
+ PAGE_SIZE order which is greater than or equal to the requested buffer
+ size. This works well for buffers up to a few hundreds kilobytes, but
+ for larger buffers it just a memory waste. With this parameter you can
+ specify the maximum PAGE_SIZE order for contiguous buffers. Larger
+ buffers will be aligned only to this specified order. The order is
+ expressed as a power of two multiplied by the PAGE_SIZE.
+
+ For example, if your system defaults to 4KiB pages, the order value
+ of 8 means that the buffers will be aligned up to 1MiB only.
+
+ If unsure, leave the default value "8".
+
+endif
+
+config DMA_API_DEBUG
+ bool "Enable debugging of DMA-API usage"
+ select NEED_DMA_MAP_STATE
+ help
+ Enable this option to debug the use of the DMA API by device drivers.
+ With this option you will be able to detect common bugs in device
+ drivers like double-freeing of DMA mappings or freeing mappings that
+ were never allocated.
+
+ This also attempts to catch cases where a page owned by DMA is
+ accessed by the cpu in a way that could cause data corruption. For
+ example, this enables cow_user_page() to check that the source page is
+ not undergoing DMA.
+
+ This option causes a performance degradation. Use only if you want to
+ debug device drivers and dma interactions.
+
+ If unsure, say N.
+
+config DMA_API_DEBUG_SG
+ bool "Debug DMA scatter-gather usage"
+ default y
+ depends on DMA_API_DEBUG
+ help
+ Perform extra checking that callers of dma_map_sg() have respected the
+ appropriate segment length/boundary limits for the given device when
+ preparing DMA scatterlists.
+
+ This is particularly likely to have been overlooked in cases where the
+ dma_map_sg() API is used for general bulk mapping of pages rather than
+ preparing literal scatter-gather descriptors, where there is a risk of
+ unexpected behaviour from DMA API implementations if the scatterlist
+ is technically out-of-spec.
+
+ If unsure, say N.
diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile
index 72ff6e46aa86..d237cf3dc181 100644
--- a/kernel/dma/Makefile
+++ b/kernel/dma/Makefile
@@ -2,7 +2,7 @@
obj-$(CONFIG_HAS_DMA) += mapping.o direct.o dummy.o
obj-$(CONFIG_DMA_CMA) += contiguous.o
-obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += coherent.o
+obj-$(CONFIG_DMA_DECLARE_COHERENT) += coherent.o
obj-$(CONFIG_DMA_VIRT_OPS) += virt.o
obj-$(CONFIG_DMA_API_DEBUG) += debug.o
obj-$(CONFIG_SWIOTLB) += swiotlb.o
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index 66f0fb7e9a3a..29fd6590dc1e 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -14,7 +14,6 @@ struct dma_coherent_mem {
dma_addr_t device_base;
unsigned long pfn_base;
int size;
- int flags;
unsigned long *bitmap;
spinlock_t spinlock;
bool use_dev_dma_pfn_offset;
@@ -38,12 +37,12 @@ static inline dma_addr_t dma_get_device_base(struct device *dev,
return mem->device_base;
}
-static int dma_init_coherent_memory(
- phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags,
- struct dma_coherent_mem **mem)
+static int dma_init_coherent_memory(phys_addr_t phys_addr,
+ dma_addr_t device_addr, size_t size,
+ struct dma_coherent_mem **mem)
{
struct dma_coherent_mem *dma_mem = NULL;
- void __iomem *mem_base = NULL;
+ void *mem_base = NULL;
int pages = size >> PAGE_SHIFT;
int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
int ret;
@@ -73,7 +72,6 @@ static int dma_init_coherent_memory(
dma_mem->device_base = device_addr;
dma_mem->pfn_base = PFN_DOWN(phys_addr);
dma_mem->size = pages;
- dma_mem->flags = flags;
spin_lock_init(&dma_mem->spinlock);
*mem = dma_mem;
@@ -110,12 +108,12 @@ static int dma_assign_coherent_memory(struct device *dev,
}
int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
- dma_addr_t device_addr, size_t size, int flags)
+ dma_addr_t device_addr, size_t size)
{
struct dma_coherent_mem *mem;
int ret;
- ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, &mem);
+ ret = dma_init_coherent_memory(phys_addr, device_addr, size, &mem);
if (ret)
return ret;
@@ -137,29 +135,6 @@ void dma_release_declared_memory(struct device *dev)
}
EXPORT_SYMBOL(dma_release_declared_memory);
-void *dma_mark_declared_memory_occupied(struct device *dev,
- dma_addr_t device_addr, size_t size)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
- unsigned long flags;
- int pos, err;
-
- size += device_addr & ~PAGE_MASK;
-
- if (!mem)
- return ERR_PTR(-EINVAL);
-
- spin_lock_irqsave(&mem->spinlock, flags);
- pos = PFN_DOWN(device_addr - dma_get_device_base(dev, mem));
- err = bitmap_allocate_region(mem->bitmap, pos, get_order(size));
- spin_unlock_irqrestore(&mem->spinlock, flags);
-
- if (err != 0)
- return ERR_PTR(err);
- return mem->virt_base + (pos << PAGE_SHIFT);
-}
-EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
-
static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
ssize_t size, dma_addr_t *dma_handle)
{
@@ -213,15 +188,7 @@ int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
return 0;
*ret = __dma_alloc_from_coherent(mem, size, dma_handle);
- if (*ret)
- return 1;
-
- /*
- * In the case where the allocation can not be satisfied from the
- * per-device area, try to fall back to generic memory if the
- * constraints allow it.
- */
- return mem->flags & DMA_MEMORY_EXCLUSIVE;
+ return 1;
}
void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle)
@@ -350,8 +317,7 @@ static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
if (!mem) {
ret = dma_init_coherent_memory(rmem->base, rmem->base,
- rmem->size,
- DMA_MEMORY_EXCLUSIVE, &mem);
+ rmem->size, &mem);
if (ret) {
pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
&rmem->base, (unsigned long)rmem->size / SZ_1M);
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index 23cf5361bcf1..45d51e8e26f6 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -134,17 +134,6 @@ static u32 nr_total_entries;
/* number of preallocated entries requested by kernel cmdline */
static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES;
-/* debugfs dentry's for the stuff above */
-static struct dentry *dma_debug_dent __read_mostly;
-static struct dentry *global_disable_dent __read_mostly;
-static struct dentry *error_count_dent __read_mostly;
-static struct dentry *show_all_errors_dent __read_mostly;
-static struct dentry *show_num_errors_dent __read_mostly;
-static struct dentry *num_free_entries_dent __read_mostly;
-static struct dentry *min_free_entries_dent __read_mostly;
-static struct dentry *nr_total_entries_dent __read_mostly;
-static struct dentry *filter_dent __read_mostly;
-
/* per-driver filter related state */
#define NAME_MAX_LEN 64
@@ -840,66 +829,46 @@ static const struct file_operations filter_fops = {
.llseek = default_llseek,
};
-static int dma_debug_fs_init(void)
+static int dump_show(struct seq_file *seq, void *v)
{
- dma_debug_dent = debugfs_create_dir("dma-api", NULL);
- if (!dma_debug_dent) {
- pr_err("can not create debugfs directory\n");
- return -ENOMEM;
- }
+ int idx;
- global_disable_dent = debugfs_create_bool("disabled", 0444,
- dma_debug_dent,
- &global_disable);
- if (!global_disable_dent)
- goto out_err;
-
- error_count_dent = debugfs_create_u32("error_count", 0444,
- dma_debug_dent, &error_count);
- if (!error_count_dent)
- goto out_err;
-
- show_all_errors_dent = debugfs_create_u32("all_errors", 0644,
- dma_debug_dent,
- &show_all_errors);
- if (!show_all_errors_dent)
- goto out_err;
-
- show_num_errors_dent = debugfs_create_u32("num_errors", 0644,
- dma_debug_dent,
- &show_num_errors);
- if (!show_num_errors_dent)
- goto out_err;
-
- num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444,
- dma_debug_dent,
- &num_free_entries);
- if (!num_free_entries_dent)
- goto out_err;
-
- min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444,
- dma_debug_dent,
- &min_free_entries);
- if (!min_free_entries_dent)
- goto out_err;
-
- nr_total_entries_dent = debugfs_create_u32("nr_total_entries", 0444,
- dma_debug_dent,
- &nr_total_entries);
- if (!nr_total_entries_dent)
- goto out_err;
-
- filter_dent = debugfs_create_file("driver_filter", 0644,
- dma_debug_dent, NULL, &filter_fops);
- if (!filter_dent)
- goto out_err;
+ for (idx = 0; idx < HASH_SIZE; idx++) {
+ struct hash_bucket *bucket = &dma_entry_hash[idx];
+ struct dma_debug_entry *entry;
+ unsigned long flags;
+ spin_lock_irqsave(&bucket->lock, flags);
+ list_for_each_entry(entry, &bucket->list, list) {
+ seq_printf(seq,
+ "%s %s %s idx %d P=%llx N=%lx D=%llx L=%llx %s %s\n",
+ dev_name(entry->dev),
+ dev_driver_string(entry->dev),
+ type2name[entry->type], idx,
+ phys_addr(entry), entry->pfn,
+ entry->dev_addr, entry->size,
+ dir2name[entry->direction],
+ maperr2str[entry->map_err_type]);
+ }
+ spin_unlock_irqrestore(&bucket->lock, flags);
+ }
return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dump);
-out_err:
- debugfs_remove_recursive(dma_debug_dent);
-
- return -ENOMEM;
+static void dma_debug_fs_init(void)
+{
+ struct dentry *dentry = debugfs_create_dir("dma-api", NULL);
+
+ debugfs_create_bool("disabled", 0444, dentry, &global_disable);
+ debugfs_create_u32("error_count", 0444, dentry, &error_count);
+ debugfs_create_u32("all_errors", 0644, dentry, &show_all_errors);
+ debugfs_create_u32("num_errors", 0644, dentry, &show_num_errors);
+ debugfs_create_u32("num_free_entries", 0444, dentry, &num_free_entries);
+ debugfs_create_u32("min_free_entries", 0444, dentry, &min_free_entries);
+ debugfs_create_u32("nr_total_entries", 0444, dentry, &nr_total_entries);
+ debugfs_create_file("driver_filter", 0644, dentry, NULL, &filter_fops);
+ debugfs_create_file("dump", 0444, dentry, NULL, &dump_fops);
}
static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry)
@@ -985,12 +954,7 @@ static int dma_debug_init(void)
spin_lock_init(&dma_entry_hash[i].lock);
}
- if (dma_debug_fs_init() != 0) {
- pr_err("error creating debugfs entries - disabling\n");
- global_disable = true;
-
- return 0;
- }
+ dma_debug_fs_init();
nr_pages = DIV_ROUND_UP(nr_prealloc_entries, DMA_DEBUG_DYNAMIC_ENTRIES);
for (i = 0; i < nr_pages; ++i)
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index d5bb51cf27c6..7ff807f2121c 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -355,6 +355,20 @@ out_unmap:
}
EXPORT_SYMBOL(dma_direct_map_sg);
+dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ dma_addr_t dma_addr = paddr;
+
+ if (unlikely(!dma_direct_possible(dev, dma_addr, size))) {
+ report_addr(dev, dma_addr, size);
+ return DMA_MAPPING_ERROR;
+ }
+
+ return dma_addr;
+}
+EXPORT_SYMBOL(dma_direct_map_resource);
+
/*
* Because 32-bit DMA masks are so common we expect every architecture to be
* able to satisfy them - either by not supporting more physical memory, or by