F: include/linux/dma-resv.h
K: \bdma_(?:buf|fence|resv)\b
diff --git a/include/linux/dma-buf-map.h b/include/linux/dma-buf-map.h
index 19fa0b5ae5ec..4b4b2930660b 100644
--- a/include/linux/dma-buf-map.h
+++ b/include/linux/dma-buf-map.h
@@ -263,4 +263,7 @@ static inline void dma_buf_map_incr(struct dma_buf_map *map, size_t incr)
map->vaddr += incr;
}
+/* Temporary include for API migration */
+#include <linux/iosys-map.h>
+
#endif /* __DMA_BUF_MAP_H__ */
diff --git a/include/linux/iosys-map.h b/include/linux/iosys-map.h
new file mode 100644
index 000000000000..ad1f08f8f97f
--- /dev/null
+++ b/include/linux/iosys-map.h
@@ -0,0 +1,254 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Pointer abstraction for IO/system memory
+ */
+
+#ifndef __IOSYS_MAP_H__
+#define __IOSYS_MAP_H__
+
+#include <linux/io.h>
+#include <linux/string.h>
+
+/* Temporary include while user of dma-buf-map are converted to iosys-map */
+#include <linux/dma-buf-map.h>
+
+/**
+ * DOC: overview
+ *
+ * When accessing a memory region, depending on the its location, users may have
+ * to access it with I/O operations or memory load/store operations. For
+ * example, copying to system memory could be done with memcpy(), copying to I/O
+ * memory would be done with memcpy_toio().
+ *
+ * .. code-block:: c
+ *
+ * void *vaddr = ...; // pointer to system memory
+ * memcpy(vaddr, src, len);
+ *
+ * void *vaddr_iomem = ...; // pointer to I/O memory
+ * memcpy_toio(vaddr, _iomem, src, len);
+ *
+ * The user of such pointer may not have information about the mapping of that
+ * region or may want to have a single code path to handle operations on that
+ * buffer, regardless if it's located in system or IO memory. The type
+ * :c:type:`struct iosys_map <iosys_map>` and its helpers abstract that so the
+ * buffer can be passed around to other drivers or have separate duties inside
+ * the same driver for allocation, read and write operations.
+ *
+ * Open-coding access to :c:type:`struct iosys_map <iosys_map>` is considered
+ * bad style. Rather then accessing its fields directly, use one of the provided
+ * helper functions, or implement your own. For example, instances of
+ * :c:type:`struct iosys_map <iosys_map>` can be initialized statically with
+ * IOSYS_MAP_INIT_VADDR(), or at runtime with iosys_map_set_vaddr(). These
+ * helpers will set an address in system memory.
+ *
+ * .. code-block:: c
+ *
+ * struct iosys_map map = IOSYS_MAP_INIT_VADDR(0xdeadbeaf);
+ *
+ * iosys_map_set_vaddr(&map, 0xdeadbeaf);
+ *
+ * To set an address in I/O memory, use iosys_map_set_vaddr_iomem().
+ *
+ * .. code-block:: c
+ *
+ * iosys_map_set_vaddr_iomem(&map, 0xdeadbeaf);
+ *
+ * Instances of struct iosys_map do not have to be cleaned up, but
+ * can be cleared to NULL with iosys_map_clear(). Cleared mappings
+ * always refer to system memory.
+ *
+ * .. code-block:: c
+ *
+ * iosys_map_clear(&map);
+ *
+ * Test if a mapping is valid with either iosys_map_is_set() or
+ * iosys_map_is_null().
+ *
+ * .. code-block:: c
+ *
+ * if (iosys_map_is_set(&map) != iosys_map_is_null(&map))
+ * // always true
+ *
+ * Instances of :c:type:`struct iosys_map <iosys_map>` can be compared for
+ * equality with iosys_map_is_equal(). Mappings that point to different memory
+ * spaces, system or I/O, are never equal. That's even true if both spaces are
+ * located in the same address space, both mappings contain the same address
+ * value, or both mappings refer to NULL.
+ *
+ * .. code-block:: c
+ *
+ * struct iosys_map sys_map; // refers to system memory
+ * struct iosys_map io_map; // refers to I/O memory
+ *
+ * if (iosys_map_is_equal(&sys_map, &io_map))
+ * // always false
+ *
+ * A set up instance of struct iosys_map can be used to access or manipulate the
+ * buffer memory. Depending on the location of the memory, the provided helpers
+ * will pick the correct operations. Data can be copied into the memory with
+ * iosys_map_memcpy_to(). The address can be manipulated with iosys_map_incr().
+ *
+ * .. code-block:: c
+ *
+ * const void *src = ...; // source buffer
+ * size_t len = ...; // length of src
+ *
+ * iosys_map_memcpy_to(&map, src, len);
+ * iosys_map_incr(&map, len); // go to first byte after the memcpy
+ */
+
+/**
+ * struct iosys_map - Pointer to IO/system memory
+ * @vaddr_iomem: The buffer's address if in I/O memory
+ * @vaddr: The buffer's address if in system memory
+ * @is_iomem: True if the buffer is located in I/O memory, or false
+ * otherwise.
+ */
+#define iosys_map dma_buf_map
+
+/**
+ * IOSYS_MAP_INIT_VADDR - Initializes struct iosys_map to an address in system memory
+ * @vaddr_: A system-memory address
+ */
+#define IOSYS_MAP_INIT_VADDR(vaddr_) \
+ { \
+ .vaddr = (vaddr_), \
+ .is_iomem = false, \
+ }
+
+/**
+ * iosys_map_set_vaddr - Sets a iosys mapping structure to an address in system memory
+ * @map: The iosys_map structure
+ * @vaddr: A system-memory address
+ *
+ * Sets the address and clears the I/O-memory flag.
+ */
+static inline void iosys_map_set_vaddr(struct iosys_map *map, void *vaddr)
+{
+ map->vaddr = vaddr;
+ map->is_iomem = false;
+}
+
+/**
+ * iosys_map_set_vaddr_iomem - Sets a iosys mapping structure to an address in I/O memory
+ * @map: The iosys_map structure
+ * @vaddr_iomem: An I/O-memory address
+ *
+ * Sets the address and the I/O-memory flag.
+ */
+static inline void iosys_map_set_vaddr_iomem(struct iosys_map *map,
+ void __iomem *vaddr_iomem)
+{
+ map->vaddr_iomem = vaddr_iomem;
+ map->is_iomem = true;
+}
+
+/**
+ * iosys_map_is_equal - Compares two iosys mapping structures for equality
+ * @lhs: The iosys_map structure
+ * @rhs: A iosys_map structure to compare with
+ *
+ * Two iosys mapping structures are equal if they both refer to the same type of memory
+ * and to the same address within that memory.
+ *
+ * Returns:
+ * True is both structures are equal, or false otherwise.
+ */
+static inline bool iosys_map_is_equal(const struct iosys_map *lhs,
+ const struct iosys_map *rhs)
+{
+ if (lhs->is_iomem != rhs->is_iomem)
+ return false;
+ else if (lhs->is_iomem)
+ return lhs->vaddr_iomem == rhs->vaddr_iomem;
+ else
+ return lhs->vaddr == rhs->vaddr;
+}
+
+/**
+ * iosys_map_is_null - Tests for a iosys mapping to be NULL
+ * @map: The iosys_map structure
+ *
+ * Depending on the state of struct iosys_map.is_iomem, tests if the
+ * mapping is NULL.
+ *
+ * Returns:
+ * True if the mapping is NULL, or false otherwise.
+ */
+static inline bool iosys_map_is_null(const struct iosys_map *map)
+{
+ if (map->is_iomem)
+ return !map->vaddr_iomem;
+ return !map->vaddr;
+}
+
+/**
+ * iosys_map_is_set - Tests if the iosys mapping has been set
+ * @map: The iosys_map structure
+ *
+ * Depending on the state of struct iosys_map.is_iomem, tests if the
+ * mapping has been set.
+ *
+ * Returns:
+ * True if the mapping is been set, or false otherwise.
+ */
+static inline bool iosys_map_is_set(const struct iosys_map *map)
+{
+ return !iosys_map_is_null(map);
+}
+
+/**
+ * iosys_map_clear - Clears a iosys mapping structure
+ * @map: The iosys_map structure
+ *
+ * Clears all fields to zero, including struct iosys_map.is_iomem, so
+ * mapping structures that were set to point to I/O memory are reset for
+ * system memory. Pointers are cleared to NULL. This is the default.
+ */
+static inline void iosys_map_clear(struct iosys_map *map)
+{
+ if (map->is_iomem) {
+ map->vaddr_iomem = NULL;
+ map->is_iomem = false;
+ } else {
+ map->vaddr = NULL;
+ }
+}
+
+/**
+ * iosys_map_memcpy_to - Memcpy into iosys mapping
+ * @dst: The iosys_map structure
+ * @src: The source buffer
+ * @len: The number of byte in src
+ *
+ * Copies data into a iosys mapping. The source buffer is in system
+ * memory. Depending on the buffer's location, the helper picks the correct
+ * method of accessing the memory.
+ */
+static inline void iosys_map_memcpy_to(struct iosys_map *dst, const void *src,
+ size_t len)
+{
+ if (dst->is_iomem)
+ memcpy_toio(dst->vaddr_iomem, src, len);
+ else
+ memcpy(dst->vaddr, src, len);
+}
+
+/**
+ * iosys_map_incr - Increments the address stored in a iosys mapping
+ * @map: The iosys_map structure
+ * @incr: The number of bytes to increment
+ *
+ * Increments the address stored in a iosys mapping. Depending on the
+ * buffer's location, the correct value will be updated.
+ */
+static inline void iosys_map_incr(struct iosys_map *map, size_t incr)
+{
+ if (map->is_iomem)
+ map->vaddr_iomem += incr;
+ else
+ map->vaddr += incr;
+}
+
+#endif /* __IOSYS_MAP_H__ */
