1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/slab.h> |
3 | #include <linux/types.h> |
4 | #include <linux/mm.h> |
5 | #include <linux/fs.h> |
6 | |
7 | #include <xen/page.h> |
8 | #include <xen/xenbus.h> |
9 | |
10 | #include "xenfs.h" |
11 | |
12 | static ssize_t xsd_read(struct file *file, char __user *buf, |
13 | size_t size, loff_t *off) |
14 | { |
15 | const char *str = (const char *)file->private_data; |
16 | return simple_read_from_buffer(to: buf, count: size, ppos: off, from: str, strlen(str)); |
17 | } |
18 | |
19 | static int xsd_release(struct inode *inode, struct file *file) |
20 | { |
21 | kfree(objp: file->private_data); |
22 | return 0; |
23 | } |
24 | |
25 | static int xsd_kva_open(struct inode *inode, struct file *file) |
26 | { |
27 | file->private_data = (void *)kasprintf(GFP_KERNEL, fmt: "0x%p" , |
28 | xen_store_interface); |
29 | if (!file->private_data) |
30 | return -ENOMEM; |
31 | return 0; |
32 | } |
33 | |
34 | static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma) |
35 | { |
36 | size_t size = vma->vm_end - vma->vm_start; |
37 | |
38 | if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0)) |
39 | return -EINVAL; |
40 | |
41 | if (remap_pfn_range(vma, addr: vma->vm_start, |
42 | pfn: virt_to_pfn(v: xen_store_interface), |
43 | size, vma->vm_page_prot)) |
44 | return -EAGAIN; |
45 | |
46 | return 0; |
47 | } |
48 | |
49 | const struct file_operations xsd_kva_file_ops = { |
50 | .open = xsd_kva_open, |
51 | .mmap = xsd_kva_mmap, |
52 | .read = xsd_read, |
53 | .release = xsd_release, |
54 | }; |
55 | |
56 | static int xsd_port_open(struct inode *inode, struct file *file) |
57 | { |
58 | file->private_data = (void *)kasprintf(GFP_KERNEL, fmt: "%d" , |
59 | xen_store_evtchn); |
60 | if (!file->private_data) |
61 | return -ENOMEM; |
62 | return 0; |
63 | } |
64 | |
65 | const struct file_operations xsd_port_file_ops = { |
66 | .open = xsd_port_open, |
67 | .read = xsd_read, |
68 | .release = xsd_release, |
69 | }; |
70 | |