It allows to copy data from iosys_map into the user memory, regardless whether iosys_map points to memory or I/O memory.
Signed-off-by: Michal Wajdeczko <[email protected]> --- Cc: [email protected] Cc: [email protected] Cc: Lucas De Marchi <[email protected]> --- include/linux/iosys-map.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/include/linux/iosys-map.h b/include/linux/iosys-map.h index 4696abfd311c..eb79da976211 100644 --- a/include/linux/iosys-map.h +++ b/include/linux/iosys-map.h @@ -7,6 +7,7 @@ #define __IOSYS_MAP_H__ #include <linux/compiler_types.h> +#include <linux/fs.h> #include <linux/io.h> #include <linux/string.h> @@ -312,6 +313,29 @@ static inline void iosys_map_memcpy_from(void *dst, const struct iosys_map *src, memcpy(dst, src->vaddr + src_offset, len); } +/** + * iosys_map_read_from - Copy data from iosys_map into user memory + * @to: the user space buffer to read to + * @count: the maximum number of bytes to read + * @ppos: the current position in the buffer + * @map: the iosys_map structure to read from + * @available: the size of the data in iosys_map + * + * Copies up to @count bytes from a iosys_map @map at offset @ppos into the user + * space address starting at @to. + * + * Return: On success, the number of bytes read is returned and the offset + * @ppos is advanced by this number, or negative value is returned on error. + */ +static inline ssize_t iosys_map_read_from(void __user *to, size_t count, loff_t *ppos, + const struct iosys_map *map, size_t available) +{ + if (map->is_iomem) + return simple_read_from_iomem(to, count, ppos, map->vaddr_iomem, available); + else + return simple_read_from_buffer(to, count, ppos, map->vaddr, available); +} + /** * iosys_map_incr - Increments the address stored in a iosys mapping * @map: The iosys_map structure -- 2.43.0
