Add support for multiple coherent rmems per device. This patch replaces
original dma_mem with dma_mems list in device structure to store multiple
rmems.
These multiple rmems can be assigned to the device one by one by
of_reserved_mem_device_init_by_idx() with the memory-region
declaration in device tree as below and store the rmem to the dma_mems
list.
device1@0 {
...
memory-region = <&reserved_mem0>, <&reserved_mem1>;
...
};
When driver tries to allocate memory from the rmems, looks for the first
available rmem and allocates the memory from this rmem.
Then if driver removed, of_reserved_mem_device_release() needs to be
invoked to release all the rmems assigned to the device.
Signed-off-by: Howard Yen <howardyen@xxxxxxxxxx>
---
drivers/base/core.c | 3 ++
include/linux/device.h | 5 +--
kernel/dma/coherent.c | 92 +++++++++++++++++++++++++++---------------
3 files changed, 64 insertions(+), 36 deletions(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 14d46af40f9a..d9af38d7b870 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -3108,6 +3108,9 @@ void device_initialize(struct device *dev)
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
dev->dma_coherent = dma_default_coherent;
+#endif
+#ifdef CONFIG_DMA_DECLARE_COHERENT
+ INIT_LIST_HEAD(&dev->dma_mems);
#endif
swiotlb_dev_init(dev);
}
diff --git a/include/linux/device.h b/include/linux/device.h
index 97c4b046c09d..5fa15e5adbdc 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -648,7 +648,7 @@ struct device_physical_location {
* @dma_parms: A low level driver may set these to teach IOMMU code about
* segment limitations.
* @dma_pools: Dma pools (if dma'ble device).
- * @dma_mem: Internal for coherent mem override.
+ * @dma_mems: Internal for coherent mems.
* @cma_area: Contiguous memory area for dma allocations
* @dma_io_tlb_mem: Software IO TLB allocator. Not for driver use.
* @dma_io_tlb_pools: List of transient swiotlb memory pools.
@@ -749,8 +749,7 @@ struct device {
struct list_head dma_pools; /* dma pools (if dma'ble) */
#ifdef CONFIG_DMA_DECLARE_COHERENT
- struct dma_coherent_mem *dma_mem; /* internal for coherent mem
- override */
+ struct list_head dma_mems; /* Internal for coherent mems */
#endif
#ifdef CONFIG_DMA_CMA
struct cma *cma_area; /* contiguous memory area for dma
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index ff5683a57f77..f6748a3a5eb1 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -11,22 +11,16 @@
#include <linux/dma-map-ops.h>
struct dma_coherent_mem {
- void *virt_base;
- dma_addr_t device_base;
- unsigned long pfn_base;
- int size;
- unsigned long *bitmap;
- spinlock_t spinlock;
- bool use_dev_dma_pfn_offset;
+ struct list_head node;
+ void *virt_base;
+ dma_addr_t device_base;
+ unsigned long pfn_base;
+ int size;
+ spinlock_t spinlock;
+ unsigned long *bitmap;
+ bool use_dev_dma_pfn_offset;
};
-static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *dev)
-{
- if (dev && dev->dma_mem)
- return dev->dma_mem;
- return NULL;
-}
-
static inline dma_addr_t dma_get_device_base(struct device *dev,
struct dma_coherent_mem * mem)
{
@@ -61,6 +55,7 @@ static struct dma_coherent_mem *dma_init_coherent_memory(phys_addr_t phys_addr,
dma_mem->pfn_base = PFN_DOWN(phys_addr);
dma_mem->size = pages;
dma_mem->use_dev_dma_pfn_offset = use_dma_pfn_offset;
+ INIT_LIST_HEAD(&dma_mem->node);
spin_lock_init(&dma_mem->spinlock);
return dma_mem;
@@ -90,10 +85,8 @@ static int dma_assign_coherent_memory(struct device *dev,
if (!dev)
return -ENODEV;
- if (dev->dma_mem)
- return -EBUSY;
+ list_add_tail(&mem->node, &dev->dma_mems);
- dev->dma_mem = mem;
return 0;
}
@@ -118,23 +111,28 @@ 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;
+ int retval;
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)
+ retval = dma_assign_coherent_memory(dev, mem);
+ if (retval)
_dma_release_coherent_memory(mem);
- return ret;
+ return retval;
}
void dma_release_coherent_memory(struct device *dev)
{
- if (dev) {
- _dma_release_coherent_memory(dev->dma_mem);
- dev->dma_mem = NULL;
+ struct dma_coherent_mem *mem_tmp, *q;
+
+ if (!dev)
+ return;
+
+ list_for_each_entry_safe(mem_tmp, q, &dev->dma_mems, node) {
+ list_del_init(&mem_tmp->node);
+ _dma_release_coherent_memory(mem_tmp);
}
}
@@ -187,12 +185,17 @@ static void *__dma_alloc_from_coherent(struct device *dev,
int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
dma_addr_t *dma_handle, void **ret)
{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+ struct dma_coherent_mem *mem_tmp;
- if (!mem)
+ if (list_empty(&dev->dma_mems))
return 0;
- *ret = __dma_alloc_from_coherent(dev, mem, size, dma_handle);
+ list_for_each_entry(mem_tmp, &dev->dma_mems, node) {
+ *ret = __dma_alloc_from_coherent(dev, mem_tmp, size, dma_handle);
+ if (*ret)
+ break;
+ }
+
return 1;
}
@@ -226,9 +229,16 @@ static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
*/
int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr)
{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+ struct dma_coherent_mem *mem_tmp;
+ int retval = 0;
- return __dma_release_from_coherent(mem, order, vaddr);
+ list_for_each_entry(mem_tmp, &dev->dma_mems, node) {
+ retval = __dma_release_from_coherent(mem_tmp, order, vaddr);
+ if (retval == 1)
+ break;
+ }
+
+ return retval;
}
static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
@@ -271,9 +281,16 @@ static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
void *vaddr, size_t size, int *ret)
{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+ struct dma_coherent_mem *mem_tmp;
+ int retval = 0;
- return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret);
+ list_for_each_entry(mem_tmp, &dev->dma_mems, node) {
+ retval = __dma_mmap_from_coherent(mem_tmp, vma, vaddr, size, ret);
+ if (retval == 1)
+ break;
+ }
+
+ return retval;
}
#ifdef CONFIG_DMA_GLOBAL_POOL
@@ -351,8 +368,17 @@ static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
static void rmem_dma_device_release(struct reserved_mem *rmem,
struct device *dev)
{
- if (dev)
- dev->dma_mem = NULL;
+ struct dma_coherent_mem *mem_tmp, *q;
+
+ if (!dev)
+ return;
+
+ list_for_each_entry_safe(mem_tmp, q, &dev->dma_mems, node) {
+ if (mem_tmp == rmem->priv) {
+ list_del_init(&mem_tmp->node);
+ break;
+ }
+ }
}
static const struct reserved_mem_ops rmem_dma_ops = {
--
2.44.0.278.ge034bb2e1d-goog
