[PATCH v9 03/14] swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used

From: Claire Chang
Date: Fri Jun 11 2021 - 11:29:03 EST


Always have the pointer to the swiotlb pool used in struct device. This
could help simplify the code for other pools.

Signed-off-by: Claire Chang <tientzu@xxxxxxxxxxxx>
---
drivers/of/device.c | 3 +++
include/linux/device.h | 4 ++++
include/linux/swiotlb.h | 8 ++++++++
kernel/dma/swiotlb.c | 8 ++++----
4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/of/device.c b/drivers/of/device.c
index c5a9473a5fb1..1defdf15ba95 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,

arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);

+ if (IS_ENABLED(CONFIG_SWIOTLB))
+ swiotlb_set_io_tlb_default_mem(dev);
+
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);
diff --git a/include/linux/device.h b/include/linux/device.h
index 4443e12238a0..2e9a378c9100 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -432,6 +432,7 @@ struct dev_links_info {
* @dma_pools: Dma pools (if dma'ble device).
* @dma_mem: Internal for coherent mem override.
* @cma_area: Contiguous memory area for dma allocations
+ * @dma_io_tlb_mem: Pointer to the swiotlb pool used. Not for driver use.
* @archdata: For arch-specific additions.
* @of_node: Associated device tree node.
* @fwnode: Associated device node supplied by platform firmware.
@@ -540,6 +541,9 @@ struct device {
#ifdef CONFIG_DMA_CMA
struct cma *cma_area; /* contiguous memory area for dma
allocations */
+#endif
+#ifdef CONFIG_SWIOTLB
+ struct io_tlb_mem *dma_io_tlb_mem;
#endif
/* arch specific additions */
struct dev_archdata archdata;
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 216854a5e513..008125ccd509 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -108,6 +108,11 @@ static inline bool is_swiotlb_buffer(phys_addr_t paddr)
return mem && paddr >= mem->start && paddr < mem->end;
}

+static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+{
+ dev->dma_io_tlb_mem = io_tlb_default_mem;
+}
+
void __init swiotlb_exit(void);
unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
@@ -119,6 +124,9 @@ static inline bool is_swiotlb_buffer(phys_addr_t paddr)
{
return false;
}
+static inline void swiotlb_set_io_tlb_default_mem(struct device *dev)
+{
+}
static inline void swiotlb_exit(void)
{
}
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 8a3e2b3b246d..29b950ab1351 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -344,7 +344,7 @@ void __init swiotlb_exit(void)
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;
@@ -426,7 +426,7 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
static int 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;
@@ -503,7 +503,7 @@ 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;
@@ -554,7 +554,7 @@ 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)
{
- struct io_tlb_mem *mem = io_tlb_default_mem;
+ struct io_tlb_mem *mem = hwdev->dma_io_tlb_mem;
unsigned long flags;
unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
--
2.32.0.272.g935e593368-goog