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

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 <redacted>
---
 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