diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h index 52a5da99a205..1d3a37234ace 100644 --- a/include/linux/io_uring_types.h +++ b/include/linux/io_uring_types.h @@ -75,6 +75,12 @@ struct io_hash_table { unsigned hash_bits; }; +struct io_mapped_region { + struct page **pages; + void *vmap_ptr; + size_t nr_pages; +}; + /* * Arbitrary limit, can be raised if need be */ diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 132f5db3d4e8..5cbfd330c688 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -647,6 +647,20 @@ struct io_uring_files_update { __aligned_u64 /* __s32 * */ fds; }; +enum { + /* initialise with user provided memory pointed by user_addr */ + IORING_MEM_REGION_TYPE_USER = 1, +}; + +struct io_uring_region_desc { + __u64 user_addr; + __u64 size; + __u32 flags; + __u32 id; + __u64 mmap_offset; + __u64 __resv[4]; +}; + /* * Register a fully sparse file space, rather than pass in an array of all * -1 file descriptors. diff --git a/io_uring/memmap.c b/io_uring/memmap.c index 6ab59c60dfd0..bbd9569a0120 100644 --- a/io_uring/memmap.c +++ b/io_uring/memmap.c @@ -12,6 +12,7 @@ #include "memmap.h" #include "kbuf.h" +#include "rsrc.h" static void *io_mem_alloc_compound(struct page **pages, int nr_pages, size_t size, gfp_t gfp) @@ -194,6 +195,72 @@ void *__io_uaddr_map(struct page ***pages, unsigned short *npages, return ERR_PTR(-ENOMEM); } +void io_free_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr) +{ + if (mr->pages) { + unpin_user_pages(mr->pages, mr->nr_pages); + kvfree(mr->pages); + } + if (mr->vmap_ptr) + vunmap(mr->vmap_ptr); + if (mr->nr_pages && ctx->user) + __io_unaccount_mem(ctx->user, mr->nr_pages); + + memset(mr, 0, sizeof(*mr)); +} + +int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, + struct io_uring_region_desc *reg) +{ + int pages_accounted = 0; + struct page **pages; + int nr_pages, ret; + void *vptr; + u64 end; + + if (WARN_ON_ONCE(mr->pages || mr->vmap_ptr || mr->nr_pages)) + return -EFAULT; + if (memchr_inv(®->__resv, 0, sizeof(reg->__resv))) + return -EINVAL; + if (reg->flags != IORING_MEM_REGION_TYPE_USER) + return -EINVAL; + if (!reg->user_addr) + return -EFAULT; + if (!reg->size || reg->mmap_offset || reg->id) + return -EINVAL; + if ((reg->size >> PAGE_SHIFT) > INT_MAX) + return E2BIG; + if ((reg->user_addr | reg->size) & ~PAGE_MASK) + return -EINVAL; + if (check_add_overflow(reg->user_addr, reg->size, &end)) + return -EOVERFLOW; + + pages = io_pin_pages(reg->user_addr, reg->size, &nr_pages); + if (IS_ERR(pages)) + return PTR_ERR(pages); + + if (ctx->user) { + ret = __io_account_mem(ctx->user, nr_pages); + if (ret) + goto out_free; + pages_accounted = nr_pages; + } + + vptr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL); + if (!vptr) + goto out_free; + + mr->pages = pages; + mr->vmap_ptr = vptr; + mr->nr_pages = nr_pages; + return 0; +out_free: + if (pages_accounted) + __io_unaccount_mem(ctx->user, pages_accounted); + io_pages_free(&pages, nr_pages); + return ret; +} + static void *io_uring_validate_mmap_request(struct file *file, loff_t pgoff, size_t sz) { diff --git a/io_uring/memmap.h b/io_uring/memmap.h index 5cec5b7ac49a..f361a635b6c7 100644 --- a/io_uring/memmap.h +++ b/io_uring/memmap.h @@ -22,4 +22,18 @@ unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr, unsigned long flags); int io_uring_mmap(struct file *file, struct vm_area_struct *vma); +void io_free_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr); +int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, + struct io_uring_region_desc *reg); + +static inline void *io_region_get_ptr(struct io_mapped_region *mr) +{ + return mr->vmap_ptr; +} + +static inline bool io_region_is_set(struct io_mapped_region *mr) +{ + return !!mr->nr_pages; +} + #endif