1 /*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2016 Matthew Macy (mmacy@mattmacy.io)
4 * Copyright (c) 2017 Mellanox Technologies, Ltd.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/rwlock.h>
32
33 #include <vm/vm.h>
34 #include <vm/pmap.h>
35 #include <vm/vm_object.h>
36 #include <vm/vm_map.h>
37 #include <vm/vm_page.h>
38 #include <vm/vm_pager.h>
39
40 #include <linux/fs.h>
41 #include <linux/mm.h>
42 #include <linux/shmem_fs.h>
43
44 struct page *
linux_shmem_read_mapping_page_gfp(vm_object_t obj,int pindex,gfp_t gfp)45 linux_shmem_read_mapping_page_gfp(vm_object_t obj, int pindex, gfp_t gfp)
46 {
47 struct page *page;
48 int rv;
49
50 if ((gfp & GFP_NOWAIT) != 0)
51 panic("GFP_NOWAIT is unimplemented");
52
53 VM_OBJECT_WLOCK(obj);
54 rv = vm_page_grab_valid(&page, obj, pindex, VM_ALLOC_NORMAL |
55 VM_ALLOC_NOBUSY | VM_ALLOC_WIRED);
56 VM_OBJECT_WUNLOCK(obj);
57 if (rv != VM_PAGER_OK)
58 return (ERR_PTR(-EINVAL));
59 return (page);
60 }
61
62 struct linux_file *
linux_shmem_file_setup(const char * name,loff_t size,unsigned long flags)63 linux_shmem_file_setup(const char *name, loff_t size, unsigned long flags)
64 {
65 struct fileobj {
66 struct linux_file file __aligned(sizeof(void *));
67 struct vnode vnode __aligned(sizeof(void *));
68 };
69 struct fileobj *fileobj;
70 struct linux_file *filp;
71 struct vnode *vp;
72 int error;
73
74 fileobj = kzalloc(sizeof(*fileobj), GFP_KERNEL);
75 if (fileobj == NULL) {
76 error = -ENOMEM;
77 goto err_0;
78 }
79 filp = &fileobj->file;
80 vp = &fileobj->vnode;
81
82 filp->f_count = 1;
83 filp->f_vnode = vp;
84 filp->f_shmem = vm_pager_allocate(OBJT_SWAP, NULL, size,
85 VM_PROT_READ | VM_PROT_WRITE, 0, curthread->td_ucred);
86 if (filp->f_shmem == NULL) {
87 error = -ENOMEM;
88 goto err_1;
89 }
90 return (filp);
91 err_1:
92 kfree(filp);
93 err_0:
94 return (ERR_PTR(error));
95 }
96
97 static vm_ooffset_t
linux_invalidate_mapping_pages_sub(vm_object_t obj,vm_pindex_t start,vm_pindex_t end,int flags)98 linux_invalidate_mapping_pages_sub(vm_object_t obj, vm_pindex_t start,
99 vm_pindex_t end, int flags)
100 {
101 int start_count, end_count;
102
103 VM_OBJECT_WLOCK(obj);
104 start_count = obj->resident_page_count;
105 vm_object_page_remove(obj, start, end, flags);
106 end_count = obj->resident_page_count;
107 VM_OBJECT_WUNLOCK(obj);
108 return (start_count - end_count);
109 }
110
111 unsigned long
linux_invalidate_mapping_pages(vm_object_t obj,pgoff_t start,pgoff_t end)112 linux_invalidate_mapping_pages(vm_object_t obj, pgoff_t start, pgoff_t end)
113 {
114
115 return (linux_invalidate_mapping_pages_sub(obj, start, end, OBJPR_CLEANONLY));
116 }
117
118 void
linux_shmem_truncate_range(vm_object_t obj,loff_t lstart,loff_t lend)119 linux_shmem_truncate_range(vm_object_t obj, loff_t lstart, loff_t lend)
120 {
121 vm_pindex_t start = OFF_TO_IDX(lstart + PAGE_SIZE - 1);
122 vm_pindex_t end = OFF_TO_IDX(lend + 1);
123
124 (void) linux_invalidate_mapping_pages_sub(obj, start, end, 0);
125 }
126