linux/io_uring/memmap.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/io_uring.h>
#include <linux/io_uring_types.h>
#include <asm/shmparam.h>

#include "memmap.h"
#include "kbuf.h"

static void *io_mem_alloc_compound(struct page **pages, int nr_pages,
				   size_t size, gfp_t gfp)
{ … }

static void *io_mem_alloc_single(struct page **pages, int nr_pages, size_t size,
				 gfp_t gfp)
{ … }

void *io_pages_map(struct page ***out_pages, unsigned short *npages,
		   size_t size)
{ … }

void io_pages_unmap(void *ptr, struct page ***pages, unsigned short *npages,
		    bool put_pages)
{ … }

void io_pages_free(struct page ***pages, int npages)
{ … }

struct page **io_pin_pages(unsigned long uaddr, unsigned long len, int *npages)
{ … }

void *__io_uaddr_map(struct page ***pages, unsigned short *npages,
		     unsigned long uaddr, size_t size)
{ … }

static void *io_uring_validate_mmap_request(struct file *file, loff_t pgoff,
					    size_t sz)
{ … }

int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma,
			struct page **pages, int npages)
{ … }

#ifdef CONFIG_MMU

__cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
{ … }

unsigned long io_uring_get_unmapped_area(struct file *filp, unsigned long addr,
					 unsigned long len, unsigned long pgoff,
					 unsigned long flags)
{ … }

#else /* !CONFIG_MMU */

int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
{
	return is_nommu_shared_mapping(vma->vm_flags) ? 0 : -EINVAL;
}

unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
{
	return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
}

unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
					 unsigned long len, unsigned long pgoff,
					 unsigned long flags)
{
	void *ptr;

	ptr = io_uring_validate_mmap_request(file, pgoff, len);
	if (IS_ERR(ptr))
		return PTR_ERR(ptr);

	return (unsigned long) ptr;
}

#endif /* !CONFIG_MMU */