xref: /linux/io_uring/memmap.h (revision 23b0f90ba871f096474e1c27c3d14f455189d2d9)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef IO_URING_MEMMAP_H
3 #define IO_URING_MEMMAP_H
4 
5 #define IORING_MAP_OFF_PARAM_REGION		0x20000000ULL
6 #define IORING_MAP_OFF_ZCRX_REGION		0x30000000ULL
7 
8 #define IORING_OFF_ZCRX_SHIFT		16
9 
10 struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages);
11 
12 #ifndef CONFIG_MMU
13 unsigned int io_uring_nommu_mmap_capabilities(struct file *file);
14 #endif
15 unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
16 					 unsigned long len, unsigned long pgoff,
17 					 unsigned long flags);
18 int io_uring_mmap(struct file *file, struct vm_area_struct *vma);
19 
20 void io_free_region(struct user_struct *user, struct io_mapped_region *mr);
21 int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr,
22 		     struct io_uring_region_desc *reg,
23 		     unsigned long mmap_offset);
24 
25 static inline void *io_region_get_ptr(struct io_mapped_region *mr)
26 {
27 	return mr->ptr;
28 }
29 
30 static inline bool io_region_is_set(struct io_mapped_region *mr)
31 {
32 	return !!mr->nr_pages;
33 }
34 
35 static inline void io_region_publish(struct io_ring_ctx *ctx,
36 				     struct io_mapped_region *src_region,
37 				     struct io_mapped_region *dst_region)
38 {
39 	/*
40 	 * Once published mmap can find it without holding only the ->mmap_lock
41 	 * and not ->uring_lock.
42 	 */
43 	guard(mutex)(&ctx->mmap_lock);
44 	*dst_region = *src_region;
45 }
46 
47 static inline size_t io_region_size(struct io_mapped_region *mr)
48 {
49 	return (size_t) mr->nr_pages << PAGE_SHIFT;
50 }
51 
52 #endif
53