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-rw-r--r--kernel/dma/coherent.c214
1 files changed, 114 insertions, 100 deletions
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index 551b0eb7028a..c21abc77c53e 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -7,7 +7,8 @@
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
+#include <linux/dma-map-ops.h>
struct dma_coherent_mem {
void *virt_base;
@@ -19,8 +20,6 @@ struct dma_coherent_mem {
bool use_dev_dma_pfn_offset;
};
-static struct dma_coherent_mem *dma_coherent_default_memory __ro_after_init;
-
static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *dev)
{
if (dev && dev->dma_mem)
@@ -32,65 +31,56 @@ static inline dma_addr_t dma_get_device_base(struct device *dev,
struct dma_coherent_mem * mem)
{
if (mem->use_dev_dma_pfn_offset)
- return (mem->pfn_base - dev->dma_pfn_offset) << PAGE_SHIFT;
- else
- return mem->device_base;
+ return phys_to_dma(dev, PFN_PHYS(mem->pfn_base));
+ return mem->device_base;
}
-static int dma_init_coherent_memory(phys_addr_t phys_addr,
- dma_addr_t device_addr, size_t size,
- struct dma_coherent_mem **mem)
+static struct dma_coherent_mem *dma_init_coherent_memory(phys_addr_t phys_addr,
+ dma_addr_t device_addr, size_t size, bool use_dma_pfn_offset)
{
- struct dma_coherent_mem *dma_mem = NULL;
- void *mem_base = NULL;
+ struct dma_coherent_mem *dma_mem;
int pages = size >> PAGE_SHIFT;
- int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
- int ret;
+ void *mem_base;
- if (!size) {
- ret = -EINVAL;
- goto out;
- }
+ if (!size)
+ return ERR_PTR(-EINVAL);
mem_base = memremap(phys_addr, size, MEMREMAP_WC);
- if (!mem_base) {
- ret = -EINVAL;
- goto out;
- }
+ if (!mem_base)
+ return ERR_PTR(-EINVAL);
+
dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
- if (!dma_mem) {
- ret = -ENOMEM;
- goto out;
- }
- dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!dma_mem->bitmap) {
- ret = -ENOMEM;
- goto out;
- }
+ if (!dma_mem)
+ goto out_unmap_membase;
+ dma_mem->bitmap = bitmap_zalloc(pages, GFP_KERNEL);
+ if (!dma_mem->bitmap)
+ goto out_free_dma_mem;
dma_mem->virt_base = mem_base;
dma_mem->device_base = device_addr;
dma_mem->pfn_base = PFN_DOWN(phys_addr);
dma_mem->size = pages;
+ dma_mem->use_dev_dma_pfn_offset = use_dma_pfn_offset;
spin_lock_init(&dma_mem->spinlock);
- *mem = dma_mem;
- return 0;
+ return dma_mem;
-out:
+out_free_dma_mem:
kfree(dma_mem);
- if (mem_base)
- memunmap(mem_base);
- return ret;
+out_unmap_membase:
+ memunmap(mem_base);
+ pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %zd MiB\n",
+ &phys_addr, size / SZ_1M);
+ return ERR_PTR(-ENOMEM);
}
-static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
+static void _dma_release_coherent_memory(struct dma_coherent_mem *mem)
{
if (!mem)
return;
memunmap(mem->virt_base);
- kfree(mem->bitmap);
+ bitmap_free(mem->bitmap);
kfree(mem);
}
@@ -107,22 +97,45 @@ static int dma_assign_coherent_memory(struct device *dev,
return 0;
}
+/*
+ * Declare a region of memory to be handed out by dma_alloc_coherent() when it
+ * is asked for coherent memory for this device. This shall only be used
+ * from platform code, usually based on the device tree description.
+ *
+ * phys_addr is the CPU physical address to which the memory is currently
+ * assigned (this will be ioremapped so the CPU can access the region).
+ *
+ * device_addr is the DMA address the device needs to be programmed with to
+ * actually address this memory (this will be handed out as the dma_addr_t in
+ * dma_alloc_coherent()).
+ *
+ * size is the size of the area (must be a multiple of PAGE_SIZE).
+ *
+ * As a simplification for the platforms, only *one* such region of memory may
+ * be declared per device.
+ */
int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
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, &mem);
- if (ret)
- return ret;
+ mem = dma_init_coherent_memory(phys_addr, device_addr, size, false);
+ if (IS_ERR(mem))
+ return PTR_ERR(mem);
ret = dma_assign_coherent_memory(dev, mem);
if (ret)
- dma_release_coherent_memory(mem);
+ _dma_release_coherent_memory(mem);
return ret;
}
+void dma_release_coherent_memory(struct device *dev)
+{
+ if (dev)
+ _dma_release_coherent_memory(dev->dma_mem);
+}
+
static void *__dma_alloc_from_coherent(struct device *dev,
struct dma_coherent_mem *mem,
ssize_t size, dma_addr_t *dma_handle)
@@ -134,7 +147,7 @@ static void *__dma_alloc_from_coherent(struct device *dev,
spin_lock_irqsave(&mem->spinlock, flags);
- if (unlikely(size > (mem->size << PAGE_SHIFT)))
+ if (unlikely(size > ((dma_addr_t)mem->size << PAGE_SHIFT)))
goto err;
pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
@@ -144,8 +157,9 @@ static void *__dma_alloc_from_coherent(struct device *dev,
/*
* Memory was found in the coherent area.
*/
- *dma_handle = dma_get_device_base(dev, mem) + (pageno << PAGE_SHIFT);
- ret = mem->virt_base + (pageno << PAGE_SHIFT);
+ *dma_handle = dma_get_device_base(dev, mem) +
+ ((dma_addr_t)pageno << PAGE_SHIFT);
+ ret = mem->virt_base + ((dma_addr_t)pageno << PAGE_SHIFT);
spin_unlock_irqrestore(&mem->spinlock, flags);
memset(ret, 0, size);
return ret;
@@ -180,21 +194,11 @@ int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
return 1;
}
-void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
- dma_addr_t *dma_handle)
-{
- if (!dma_coherent_default_memory)
- return NULL;
-
- return __dma_alloc_from_coherent(dev, dma_coherent_default_memory, size,
- dma_handle);
-}
-
static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
int order, void *vaddr)
{
if (mem && vaddr >= mem->virt_base && vaddr <
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+ (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
unsigned long flags;
@@ -225,23 +229,14 @@ int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr)
return __dma_release_from_coherent(mem, order, vaddr);
}
-int dma_release_from_global_coherent(int order, void *vaddr)
-{
- if (!dma_coherent_default_memory)
- return 0;
-
- return __dma_release_from_coherent(dma_coherent_default_memory, order,
- vaddr);
-}
-
static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
struct vm_area_struct *vma, void *vaddr, size_t size, int *ret)
{
if (mem && vaddr >= mem->virt_base && vaddr + size <=
- (mem->virt_base + (mem->size << PAGE_SHIFT))) {
+ (mem->virt_base + ((dma_addr_t)mem->size << PAGE_SHIFT))) {
unsigned long off = vma->vm_pgoff;
int start = (vaddr - mem->virt_base) >> PAGE_SHIFT;
- int user_count = vma_pages(vma);
+ unsigned long user_count = vma_pages(vma);
int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
*ret = -ENXIO;
@@ -279,6 +274,28 @@ int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret);
}
+#ifdef CONFIG_DMA_GLOBAL_POOL
+static struct dma_coherent_mem *dma_coherent_default_memory __ro_after_init;
+
+void *dma_alloc_from_global_coherent(struct device *dev, ssize_t size,
+ dma_addr_t *dma_handle)
+{
+ if (!dma_coherent_default_memory)
+ return NULL;
+
+ return __dma_alloc_from_coherent(dev, dma_coherent_default_memory, size,
+ dma_handle);
+}
+
+int dma_release_from_global_coherent(int order, void *vaddr)
+{
+ if (!dma_coherent_default_memory)
+ return 0;
+
+ return __dma_release_from_coherent(dma_coherent_default_memory, order,
+ vaddr);
+}
+
int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr,
size_t size, int *ret)
{
@@ -289,6 +306,19 @@ int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr,
vaddr, size, ret);
}
+int dma_init_global_coherent(phys_addr_t phys_addr, size_t size)
+{
+ struct dma_coherent_mem *mem;
+
+ mem = dma_init_coherent_memory(phys_addr, phys_addr, size, true);
+ if (IS_ERR(mem))
+ return PTR_ERR(mem);
+ dma_coherent_default_memory = mem;
+ pr_info("DMA: default coherent area is set\n");
+ return 0;
+}
+#endif /* CONFIG_DMA_GLOBAL_POOL */
+
/*
* Support for reserved memory regions defined in device tree
*/
@@ -297,25 +327,22 @@ int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr,
#include <linux/of_fdt.h>
#include <linux/of_reserved_mem.h>
+#ifdef CONFIG_DMA_GLOBAL_POOL
static struct reserved_mem *dma_reserved_default_memory __initdata;
+#endif
static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
{
- struct dma_coherent_mem *mem = rmem->priv;
- int ret;
-
- if (!mem) {
- ret = dma_init_coherent_memory(rmem->base, rmem->base,
- 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);
- return ret;
- }
+ if (!rmem->priv) {
+ struct dma_coherent_mem *mem;
+
+ mem = dma_init_coherent_memory(rmem->base, rmem->base,
+ rmem->size, true);
+ if (IS_ERR(mem))
+ return PTR_ERR(mem);
+ rmem->priv = mem;
}
- mem->use_dev_dma_pfn_offset = true;
- rmem->priv = mem;
- dma_assign_coherent_memory(dev, mem);
+ dma_assign_coherent_memory(dev, rmem->priv);
return 0;
}
@@ -343,7 +370,9 @@ static int __init rmem_dma_setup(struct reserved_mem *rmem)
pr_err("Reserved memory: regions without no-map are not yet supported\n");
return -EINVAL;
}
+#endif
+#ifdef CONFIG_DMA_GLOBAL_POOL
if (of_get_flat_dt_prop(node, "linux,dma-default", NULL)) {
WARN(dma_reserved_default_memory,
"Reserved memory: region for default DMA coherent area is redefined\n");
@@ -357,31 +386,16 @@ static int __init rmem_dma_setup(struct reserved_mem *rmem)
return 0;
}
+#ifdef CONFIG_DMA_GLOBAL_POOL
static int __init dma_init_reserved_memory(void)
{
- const struct reserved_mem_ops *ops;
- int ret;
-
if (!dma_reserved_default_memory)
return -ENOMEM;
-
- ops = dma_reserved_default_memory->ops;
-
- /*
- * We rely on rmem_dma_device_init() does not propagate error of
- * dma_assign_coherent_memory() for "NULL" device.
- */
- ret = ops->device_init(dma_reserved_default_memory, NULL);
-
- if (!ret) {
- dma_coherent_default_memory = dma_reserved_default_memory->priv;
- pr_info("DMA: default coherent area is set\n");
- }
-
- return ret;
+ return dma_init_global_coherent(dma_reserved_default_memory->base,
+ dma_reserved_default_memory->size);
}
-
core_initcall(dma_init_reserved_memory);
+#endif /* CONFIG_DMA_GLOBAL_POOL */
RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup);
#endif