[v10,06/12] swiotlb: Use is_dev_swiotlb_force for swiotlb data bouncing

Commit Message

Claire Chang June 15, 2021, 1:27 p.m. UTC

Propagate the swiotlb_force setting into io_tlb_default_mem->force and
use it to determine whether to bounce the data or not. This will be
useful later to allow for different pools.

Signed-off-by: Claire Chang <[e-mail]>
---
 include/linux/swiotlb.h | 11 +++++++++++
 kernel/dma/direct.c     |  2 +-
 kernel/dma/direct.h     |  2 +-
 kernel/dma/swiotlb.c    |  4 ++++
 4 files changed, 17 insertions(+), 2 deletions(-)

Comments

Christoph Hellwig June 15, 2021, 1:39 p.m. UTC | #1

On Tue, Jun 15, 2021 at 09:27:05PM +0800, Claire Chang wrote:
> Propagate the swiotlb_force setting into io_tlb_default_mem->force and
> use it to determine whether to bounce the data or not. This will be
> useful later to allow for different pools.
> 
> Signed-off-by: Claire Chang <[e-mail]>

Looks good,

Reviewed-by: Christoph Hellwig <[e-mail]>

Patch

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index dd1c30a83058..efcd56e3a16c 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -84,6 +84,7 @@  extern enum swiotlb_force swiotlb_force;
  *		unmap calls.
  * @debugfs:	The dentry to debugfs.
  * @late_alloc:	%true if allocated using the page allocator
+ * @force:      %true if swiotlb is forced
  */
 struct io_tlb_mem {
 	phys_addr_t start;
@@ -94,6 +95,7 @@  struct io_tlb_mem {
 	spinlock_t lock;
 	struct dentry *debugfs;
 	bool late_alloc;
+	bool force;
 	struct io_tlb_slot {
 		phys_addr_t orig_addr;
 		size_t alloc_size;
@@ -109,6 +111,11 @@  static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 	return mem && paddr >= mem->start && paddr < mem->end;
 }
 
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return dev->dma_io_tlb_mem->force;
+}
+
 void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 size_t swiotlb_max_mapping_size(struct device *dev);
@@ -120,6 +127,10 @@  static inline bool is_swiotlb_buffer(struct device *dev, phys_addr_t paddr)
 {
 	return false;
 }
+static inline bool is_dev_swiotlb_force(struct device *dev)
+{
+	return false;
+}
 static inline void swiotlb_exit(void)
 {
 }
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 7a88c34d0867..3713461d6fe0 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -496,7 +496,7 @@  size_t dma_direct_max_mapping_size(struct device *dev)
 {
 	/* If SWIOTLB is active, use its maximum mapping size */
 	if (is_swiotlb_active(dev) &&
-	    (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
+	    (dma_addressing_limited(dev) || is_dev_swiotlb_force(dev)))
 		return swiotlb_max_mapping_size(dev);
 	return SIZE_MAX;
 }
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
index 13e9e7158d94..6c4d13caceb1 100644
--- a/kernel/dma/direct.h
+++ b/kernel/dma/direct.h
@@ -87,7 +87,7 @@  static inline dma_addr_t dma_direct_map_page(struct device *dev,
 	phys_addr_t phys = page_to_phys(page) + offset;
 	dma_addr_t dma_addr = phys_to_dma(dev, phys);
 
-	if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+	if (is_dev_swiotlb_force(dev))
 		return swiotlb_map(dev, phys, size, dir, attrs);
 
 	if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index d07e32020edf..5af47a8f68b8 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -179,6 +179,10 @@  static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
 	mem->end = mem->start + bytes;
 	mem->index = 0;
 	mem->late_alloc = late_alloc;
+
+	if (swiotlb_force == SWIOTLB_FORCE)
+		mem->force = true;
+
 	spin_lock_init(&mem->lock);
 	for (i = 0; i < mem->nslabs; i++) {
 		mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);