[PATCH 1/4] dma-mapping: remove dma_release_declared_memory

From: Christoph Hellwig
Date: Mon Sep 02 2019 - 16:08:06 EST


This function is entirely unused given that declared memory is
generally provided by platform setup code.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
Documentation/DMA-API.txt | 11 -----------
include/linux/dma-mapping.h | 6 ------
kernel/dma/coherent.c | 11 -----------
3 files changed, 28 deletions(-)

diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index e47c63bd4887..c0865ca664b8 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -595,17 +595,6 @@ For reasons of efficiency, most platforms choose to track the declared
region only at the granularity of a page. For smaller allocations,
you should use the dma_pool() API.

-::
-
- void
- dma_release_declared_memory(struct device *dev)
-
-Remove the memory region previously declared from the system. This
-API performs *no* in-use checking for this region and will return
-unconditionally having removed all the required structures. It is the
-driver's job to ensure that no parts of this memory region are
-currently in use.
-
Part III - Debug drivers use of the DMA-API
-------------------------------------------

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 48ebe8295987..165cd61f1c6e 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -753,7 +753,6 @@ static inline int dma_get_cache_alignment(void)
#ifdef CONFIG_DMA_DECLARE_COHERENT
int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size);
-void dma_release_declared_memory(struct device *dev);
#else
static inline int
dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
@@ -761,11 +760,6 @@ dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
{
return -ENOSYS;
}
-
-static inline void
-dma_release_declared_memory(struct device *dev)
-{
-}
#endif /* CONFIG_DMA_DECLARE_COHERENT */

static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index 29fd6590dc1e..7271cda86a37 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -124,17 +124,6 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
}
EXPORT_SYMBOL(dma_declare_coherent_memory);

-void dma_release_declared_memory(struct device *dev)
-{
- struct dma_coherent_mem *mem = dev->dma_mem;
-
- if (!mem)
- return;
- dma_release_coherent_memory(mem);
- dev->dma_mem = NULL;
-}
-EXPORT_SYMBOL(dma_release_declared_memory);
-
static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
ssize_t size, dma_addr_t *dma_handle)
{
--
2.20.1