[v3,1/2] dma-mapping: export dma_addressing_limited()

Message ID 20231016125254.1875-2-justin.he@arm.com
State New
Headers
Series fix dma_addressing_limited() if dma_range_map |

Commit Message

Justin He Oct. 16, 2023, 12:52 p.m. UTC
  This is a preparatory patch to move dma_addressing_limited so that it is
exported instead of a new low-level helper.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jia He <justin.he@arm.com>
---
 include/linux/dma-mapping.h | 19 +++++--------------
 kernel/dma/mapping.c        | 15 +++++++++++++++
 2 files changed, 20 insertions(+), 14 deletions(-)
  

Comments

Christoph Hellwig Oct. 23, 2023, 6:09 a.m. UTC | #1
On Mon, Oct 16, 2023 at 12:52:53PM +0000, Jia He wrote:
> This is a preparatory patch to move dma_addressing_limited so that it is
> exported instead of a new low-level helper.

So while this exports dma_addressing_limited that's really a side effect.
The primary thing is that it moves the function out of line.
  
Justin He Oct. 25, 2023, 3:11 p.m. UTC | #2
> -----Original Message-----
> From: Christoph Hellwig <hch@lst.de>
> Sent: Monday, October 23, 2023 2:09 PM
> To: Justin He <Justin.He@arm.com>
> Cc: Christoph Hellwig <hch@lst.de>; Marek Szyprowski
> <m.szyprowski@samsung.com>; Robin Murphy <Robin.Murphy@arm.com>;
> iommu@lists.linux.dev; linux-kernel@vger.kernel.org; nd <nd@arm.com>
> Subject: Re: [PATCH v3 1/2] dma-mapping: export dma_addressing_limited()
> 
> On Mon, Oct 16, 2023 at 12:52:53PM +0000, Jia He wrote:
> > This is a preparatory patch to move dma_addressing_limited so that it
> > is exported instead of a new low-level helper.
> 
> So while this exports dma_addressing_limited that's really a side effect.
> The primary thing is that it moves the function out of line.
Ok, I will update the commit msg.
Thanks for the comments! 


--
Cheers,
Justin (Jia He)
  

Patch

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index f0ccca16a0ac..4a658de44ee9 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -144,6 +144,7 @@  bool dma_pci_p2pdma_supported(struct device *dev);
 int dma_set_mask(struct device *dev, u64 mask);
 int dma_set_coherent_mask(struct device *dev, u64 mask);
 u64 dma_get_required_mask(struct device *dev);
+bool dma_addressing_limited(struct device *dev);
 size_t dma_max_mapping_size(struct device *dev);
 size_t dma_opt_mapping_size(struct device *dev);
 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
@@ -264,6 +265,10 @@  static inline u64 dma_get_required_mask(struct device *dev)
 {
 	return 0;
 }
+static inline bool dma_addressing_limited(struct device *dev)
+{
+	return false;
+}
 static inline size_t dma_max_mapping_size(struct device *dev)
 {
 	return 0;
@@ -465,20 +470,6 @@  static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
 	return dma_set_mask_and_coherent(dev, mask);
 }
 
-/**
- * dma_addressing_limited - return if the device is addressing limited
- * @dev:	device to check
- *
- * Return %true if the devices DMA mask is too small to address all memory in
- * the system, else %false.  Lack of addressing bits is the prime reason for
- * bounce buffering, but might not be the only one.
- */
-static inline bool dma_addressing_limited(struct device *dev)
-{
-	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
-			    dma_get_required_mask(dev);
-}
-
 static inline unsigned int dma_get_max_seg_size(struct device *dev)
 {
 	if (dev->dma_parms && dev->dma_parms->max_segment_size)
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index e323ca48f7f2..5bfe782f9a7f 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -793,6 +793,21 @@  int dma_set_coherent_mask(struct device *dev, u64 mask)
 }
 EXPORT_SYMBOL(dma_set_coherent_mask);
 
+/**
+ * dma_addressing_limited - return if the device is addressing limited
+ * @dev:	device to check
+ *
+ * Return %true if the devices DMA mask is too small to address all memory in
+ * the system, else %false.  Lack of addressing bits is the prime reason for
+ * bounce buffering, but might not be the only one.
+ */
+bool dma_addressing_limited(struct device *dev)
+{
+	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
+			    dma_get_required_mask(dev);
+}
+EXPORT_SYMBOL(dma_addressing_limited);
+
 size_t dma_max_mapping_size(struct device *dev)
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);