dma-buf-map: remove renamed header file
commit7938f42181("dma-buf-map: Rename to iosys-map") already renamed this file, but it got brought back by a merge. Delete it for real this time. Fixes:30424ebae8("Merge tag 'drm-intel-gt-next-2022-02-17' of git://anongit.freedesktop.org/drm/drm-intel into drm-intel-next") Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Cc: dri-devel@lists.freedesktop.org Signed-off-by: Karol Herbst <kherbst@redhat.com> Reviewed-by: Michel Dänzer <mdaenzer@redhat.com> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20220411134404.524776-1-kherbst@redhat.com
This commit is contained in:
Karol Herbst
parent
0220749180
commit
f8e6b7babf
@ -1,266 +0,0 @@
|
||||
/* SPDX-License-Identifier: GPL-2.0-only */
|
||||
/*
|
||||
* Pointer to dma-buf-mapped memory, plus helpers.
|
||||
*/
|
||||
|
||||
#ifndef __DMA_BUF_MAP_H__
|
||||
#define __DMA_BUF_MAP_H__
|
||||
|
||||
#include <linux/io.h>
|
||||
#include <linux/string.h>
|
||||
|
||||
/**
|
||||
* DOC: overview
|
||||
*
|
||||
* Calling dma-buf's vmap operation returns a pointer to the buffer's memory.
|
||||
* Depending on the location of the buffer, 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);
|
||||
*
|
||||
* When using dma-buf's vmap operation, the returned pointer is encoded as
|
||||
* :c:type:`struct dma_buf_map <dma_buf_map>`.
|
||||
* :c:type:`struct dma_buf_map <dma_buf_map>` stores the buffer's address in
|
||||
* system or I/O memory and a flag that signals the required method of
|
||||
* accessing the buffer. Use the returned instance and the helper functions
|
||||
* to access the buffer's memory in the correct way.
|
||||
*
|
||||
* The type :c:type:`struct dma_buf_map <dma_buf_map>` and its helpers are
|
||||
* actually independent from the dma-buf infrastructure. When sharing buffers
|
||||
* among devices, drivers have to know the location of the memory to access
|
||||
* the buffers in a safe way. :c:type:`struct dma_buf_map <dma_buf_map>`
|
||||
* solves this problem for dma-buf and its users. If other drivers or
|
||||
* sub-systems require similar functionality, the type could be generalized
|
||||
* and moved to a more prominent header file.
|
||||
*
|
||||
* Open-coding access to :c:type:`struct dma_buf_map <dma_buf_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 dma_buf_map <dma_buf_map>` can be initialized
|
||||
* statically with DMA_BUF_MAP_INIT_VADDR(), or at runtime with
|
||||
* dma_buf_map_set_vaddr(). These helpers will set an address in system memory.
|
||||
*
|
||||
* .. code-block:: c
|
||||
*
|
||||
* struct dma_buf_map map = DMA_BUF_MAP_INIT_VADDR(0xdeadbeaf);
|
||||
*
|
||||
* dma_buf_map_set_vaddr(&map, 0xdeadbeaf);
|
||||
*
|
||||
* To set an address in I/O memory, use dma_buf_map_set_vaddr_iomem().
|
||||
*
|
||||
* .. code-block:: c
|
||||
*
|
||||
* dma_buf_map_set_vaddr_iomem(&map, 0xdeadbeaf);
|
||||
*
|
||||
* Instances of struct dma_buf_map do not have to be cleaned up, but
|
||||
* can be cleared to NULL with dma_buf_map_clear(). Cleared mappings
|
||||
* always refer to system memory.
|
||||
*
|
||||
* .. code-block:: c
|
||||
*
|
||||
* dma_buf_map_clear(&map);
|
||||
*
|
||||
* Test if a mapping is valid with either dma_buf_map_is_set() or
|
||||
* dma_buf_map_is_null().
|
||||
*
|
||||
* .. code-block:: c
|
||||
*
|
||||
* if (dma_buf_map_is_set(&map) != dma_buf_map_is_null(&map))
|
||||
* // always true
|
||||
*
|
||||
* Instances of :c:type:`struct dma_buf_map <dma_buf_map>` can be compared
|
||||
* for equality with dma_buf_map_is_equal(). Mappings the 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 dma_buf_map sys_map; // refers to system memory
|
||||
* struct dma_buf_map io_map; // refers to I/O memory
|
||||
*
|
||||
* if (dma_buf_map_is_equal(&sys_map, &io_map))
|
||||
* // always false
|
||||
*
|
||||
* A set up instance of struct dma_buf_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 dma_buf_map_memcpy_to(). The address can be manipulated with
|
||||
* dma_buf_map_incr().
|
||||
*
|
||||
* .. code-block:: c
|
||||
*
|
||||
* const void *src = ...; // source buffer
|
||||
* size_t len = ...; // length of src
|
||||
*
|
||||
* dma_buf_map_memcpy_to(&map, src, len);
|
||||
* dma_buf_map_incr(&map, len); // go to first byte after the memcpy
|
||||
*/
|
||||
|
||||
/**
|
||||
* struct dma_buf_map - Pointer to vmap'ed dma-buf 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 dma-buf memory is located in I/O
|
||||
* memory, or false otherwise.
|
||||
*/
|
||||
struct dma_buf_map {
|
||||
union {
|
||||
void __iomem *vaddr_iomem;
|
||||
void *vaddr;
|
||||
};
|
||||
bool is_iomem;
|
||||
};
|
||||
|
||||
/**
|
||||
* DMA_BUF_MAP_INIT_VADDR - Initializes struct dma_buf_map to an address in system memory
|
||||
* @vaddr_: A system-memory address
|
||||
*/
|
||||
#define DMA_BUF_MAP_INIT_VADDR(vaddr_) \
|
||||
{ \
|
||||
.vaddr = (vaddr_), \
|
||||
.is_iomem = false, \
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_set_vaddr - Sets a dma-buf mapping structure to an address in system memory
|
||||
* @map: The dma-buf mapping structure
|
||||
* @vaddr: A system-memory address
|
||||
*
|
||||
* Sets the address and clears the I/O-memory flag.
|
||||
*/
|
||||
static inline void dma_buf_map_set_vaddr(struct dma_buf_map *map, void *vaddr)
|
||||
{
|
||||
map->vaddr = vaddr;
|
||||
map->is_iomem = false;
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_set_vaddr_iomem - Sets a dma-buf mapping structure to an address in I/O memory
|
||||
* @map: The dma-buf mapping structure
|
||||
* @vaddr_iomem: An I/O-memory address
|
||||
*
|
||||
* Sets the address and the I/O-memory flag.
|
||||
*/
|
||||
static inline void dma_buf_map_set_vaddr_iomem(struct dma_buf_map *map,
|
||||
void __iomem *vaddr_iomem)
|
||||
{
|
||||
map->vaddr_iomem = vaddr_iomem;
|
||||
map->is_iomem = true;
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_is_equal - Compares two dma-buf mapping structures for equality
|
||||
* @lhs: The dma-buf mapping structure
|
||||
* @rhs: A dma-buf mapping structure to compare with
|
||||
*
|
||||
* Two dma-buf 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 dma_buf_map_is_equal(const struct dma_buf_map *lhs,
|
||||
const struct dma_buf_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;
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_is_null - Tests for a dma-buf mapping to be NULL
|
||||
* @map: The dma-buf mapping structure
|
||||
*
|
||||
* Depending on the state of struct dma_buf_map.is_iomem, tests if the
|
||||
* mapping is NULL.
|
||||
*
|
||||
* Returns:
|
||||
* True if the mapping is NULL, or false otherwise.
|
||||
*/
|
||||
static inline bool dma_buf_map_is_null(const struct dma_buf_map *map)
|
||||
{
|
||||
if (map->is_iomem)
|
||||
return !map->vaddr_iomem;
|
||||
return !map->vaddr;
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_is_set - Tests is the dma-buf mapping has been set
|
||||
* @map: The dma-buf mapping structure
|
||||
*
|
||||
* Depending on the state of struct dma_buf_map.is_iomem, tests if the
|
||||
* mapping has been set.
|
||||
*
|
||||
* Returns:
|
||||
* True if the mapping is been set, or false otherwise.
|
||||
*/
|
||||
static inline bool dma_buf_map_is_set(const struct dma_buf_map *map)
|
||||
{
|
||||
return !dma_buf_map_is_null(map);
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_clear - Clears a dma-buf mapping structure
|
||||
* @map: The dma-buf mapping structure
|
||||
*
|
||||
* Clears all fields to zero; including struct dma_buf_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 dma_buf_map_clear(struct dma_buf_map *map)
|
||||
{
|
||||
if (map->is_iomem) {
|
||||
map->vaddr_iomem = NULL;
|
||||
map->is_iomem = false;
|
||||
} else {
|
||||
map->vaddr = NULL;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_memcpy_to - Memcpy into dma-buf mapping
|
||||
* @dst: The dma-buf mapping structure
|
||||
* @src: The source buffer
|
||||
* @len: The number of byte in src
|
||||
*
|
||||
* Copies data into a dma-buf 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 dma_buf_map_memcpy_to(struct dma_buf_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);
|
||||
}
|
||||
|
||||
/**
|
||||
* dma_buf_map_incr - Increments the address stored in a dma-buf mapping
|
||||
* @map: The dma-buf mapping structure
|
||||
* @incr: The number of bytes to increment
|
||||
*
|
||||
* Increments the address stored in a dma-buf mapping. Depending on the
|
||||
* buffer's location, the correct value will be updated.
|
||||
*/
|
||||
static inline void dma_buf_map_incr(struct dma_buf_map *map, size_t incr)
|
||||
{
|
||||
if (map->is_iomem)
|
||||
map->vaddr_iomem += incr;
|
||||
else
|
||||
map->vaddr += incr;
|
||||
}
|
||||
|
||||
#endif /* __DMA_BUF_MAP_H__ */
|
||||
Loading…
Reference in New Issue
Block a user