dma-mapping: merge <linux/dma-contiguous.h> into <linux/dma-map-ops.h>

Merge dma-contiguous.h into dma-map-ops.h, after removing the comment
describing the contiguous allocator into kernel/dma/contigous.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>

2 files changed, 65 insertions, 135 deletions

diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h
deleted file mode 100644
index f9ce1ee58d41..000000000000
--- a/include/linux/dma-contiguous.h
+++ /dev/null
@@ -1,135 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef __LINUX_CMA_H
-#define __LINUX_CMA_H
-
-/*
- * Contiguous Memory Allocator for DMA mapping framework
- * Copyright (c) 2010-2011 by Samsung Electronics.
- * Written by:
- *	Marek Szyprowski <m.szyprowski@samsung.com>
- *	Michal Nazarewicz <mina86@mina86.com>
- */
-
-/*
- * Contiguous Memory Allocator
- *
- *   The Contiguous Memory Allocator (CMA) makes it possible to
- *   allocate big contiguous chunks of memory after the system has
- *   booted.
- *
- * Why is it needed?
- *
- *   Various devices on embedded systems have no scatter-getter and/or
- *   IO map support and require contiguous blocks of memory to
- *   operate.  They include devices such as cameras, hardware video
- *   coders, etc.
- *
- *   Such devices often require big memory buffers (a full HD frame
- *   is, for instance, more then 2 mega pixels large, i.e. more than 6
- *   MB of memory), which makes mechanisms such as kmalloc() or
- *   alloc_page() ineffective.
- *
- *   At the same time, a solution where a big memory region is
- *   reserved for a device is suboptimal since often more memory is
- *   reserved then strictly required and, moreover, the memory is
- *   inaccessible to page system even if device drivers don't use it.
- *
- *   CMA tries to solve this issue by operating on memory regions
- *   where only movable pages can be allocated from.  This way, kernel
- *   can use the memory for pagecache and when device driver requests
- *   it, allocated pages can be migrated.
- *
- * Driver usage
- *
- *   CMA should not be used by the device drivers directly. It is
- *   only a helper framework for dma-mapping subsystem.
- *
- *   For more information, see kernel-docs in kernel/dma/contiguous.c
- */
-
-#ifdef __KERNEL__
-
-#include <linux/device.h>
-#include <linux/mm.h>
-
-struct cma;
-struct page;
-
-#ifdef CONFIG_DMA_CMA
-
-extern struct cma *dma_contiguous_default_area;
-
-static inline struct cma *dev_get_cma_area(struct device *dev)
-{
-	if (dev && dev->cma_area)
-		return dev->cma_area;
-	return dma_contiguous_default_area;
-}
-
-void dma_contiguous_reserve(phys_addr_t addr_limit);
-
-int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
-				       phys_addr_t limit, struct cma **res_cma,
-				       bool fixed);
-
-struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
-				       unsigned int order, bool no_warn);
-bool dma_release_from_contiguous(struct device *dev, struct page *pages,
-				 int count);
-struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp);
-void dma_free_contiguous(struct device *dev, struct page *page, size_t size);
-
-#else
-
-static inline struct cma *dev_get_cma_area(struct device *dev)
-{
-	return NULL;
-}
-
-static inline void dma_contiguous_reserve(phys_addr_t limit) { }
-
-static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
-				       phys_addr_t limit, struct cma **res_cma,
-				       bool fixed)
-{
-	return -ENOSYS;
-}
-
-static inline
-struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
-				       unsigned int order, bool no_warn)
-{
-	return NULL;
-}
-
-static inline
-bool dma_release_from_contiguous(struct device *dev, struct page *pages,
-				 int count)
-{
-	return false;
-}
-
-/* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */
-static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size,
-		gfp_t gfp)
-{
-	return NULL;
-}
-
-static inline void dma_free_contiguous(struct device *dev, struct page *page,
-		size_t size)
-{
-	__free_pages(page, get_order(size));
-}
-
-#endif
-
-#ifdef CONFIG_DMA_PERNUMA_CMA
-void dma_pernuma_cma_reserve(void);
-#else
-static inline void dma_pernuma_cma_reserve(void) { }
-#endif
-
-#endif
-
-#endif
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 4b4ba5bdcf6a..474fc81bd492 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -8,6 +8,8 @@
 
 #include <linux/dma-mapping.h>
 
+struct cma;
+
 struct dma_map_ops {
 	void *(*alloc)(struct device *dev, size_t size,
 			dma_addr_t *dma_handle, gfp_t gfp,
@@ -94,6 +96,69 @@ static inline void set_dma_ops(struct device *dev,
 }
 #endif /* CONFIG_DMA_OPS */
 
+#ifdef CONFIG_DMA_CMA
+extern struct cma *dma_contiguous_default_area;
+
+static inline struct cma *dev_get_cma_area(struct device *dev)
+{
+	if (dev && dev->cma_area)
+		return dev->cma_area;
+	return dma_contiguous_default_area;
+}
+
+void dma_contiguous_reserve(phys_addr_t addr_limit);
+int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
+		phys_addr_t limit, struct cma **res_cma, bool fixed);
+
+struct page *dma_alloc_from_contiguous(struct device *dev, size_t count,
+				       unsigned int order, bool no_warn);
+bool dma_release_from_contiguous(struct device *dev, struct page *pages,
+				 int count);
+struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp);
+void dma_free_contiguous(struct device *dev, struct page *page, size_t size);
+#else /* CONFIG_DMA_CMA */
+static inline struct cma *dev_get_cma_area(struct device *dev)
+{
+	return NULL;
+}
+static inline void dma_contiguous_reserve(phys_addr_t limit)
+{
+}
+static inline int dma_contiguous_reserve_area(phys_addr_t size,
+		phys_addr_t base, phys_addr_t limit, struct cma **res_cma,
+		bool fixed)
+{
+	return -ENOSYS;
+}
+static inline struct page *dma_alloc_from_contiguous(struct device *dev,
+		size_t count, unsigned int order, bool no_warn)
+{
+	return NULL;
+}
+static inline bool dma_release_from_contiguous(struct device *dev,
+		struct page *pages, int count)
+{
+	return false;
+}
+/* Use fallback alloc() and free() when CONFIG_DMA_CMA=n */
+static inline struct page *dma_alloc_contiguous(struct device *dev, size_t size,
+		gfp_t gfp)
+{
+	return NULL;
+}
+static inline void dma_free_contiguous(struct device *dev, struct page *page,
+		size_t size)
+{
+	__free_pages(page, get_order(size));
+}
+#endif /* CONFIG_DMA_CMA*/
+
+#ifdef CONFIG_DMA_PERNUMA_CMA
+void dma_pernuma_cma_reserve(void);
+#else
+static inline void dma_pernuma_cma_reserve(void) { }
+#endif /* CONFIG_DMA_PERNUMA_CMA */
+
 #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);