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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * mmap.c | |
3 | * | |
4 | * Copyright (C) 1995, 1996 by Volker Lendecke | |
5 | * Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache | |
6 | * | |
7 | */ | |
8 | ||
9 | #include <linux/stat.h> | |
10 | #include <linux/time.h> | |
11 | #include <linux/kernel.h> | |
5a0e3ad6 | 12 | #include <linux/gfp.h> |
1da177e4 LT |
13 | #include <linux/mm.h> |
14 | #include <linux/shm.h> | |
15 | #include <linux/errno.h> | |
16 | #include <linux/mman.h> | |
17 | #include <linux/string.h> | |
1da177e4 | 18 | #include <linux/fcntl.h> |
456f998e | 19 | #include <linux/memcontrol.h> |
1da177e4 | 20 | |
1da177e4 LT |
21 | #include <asm/uaccess.h> |
22 | #include <asm/system.h> | |
23 | ||
32c419d9 AV |
24 | #include "ncp_fs.h" |
25 | ||
1da177e4 LT |
26 | /* |
27 | * Fill in the supplied page for mmap | |
d0217ac0 NP |
28 | * XXX: how are we excluding truncate/invalidate here? Maybe need to lock |
29 | * page? | |
1da177e4 | 30 | */ |
d0217ac0 NP |
31 | static int ncp_file_mmap_fault(struct vm_area_struct *area, |
32 | struct vm_fault *vmf) | |
1da177e4 LT |
33 | { |
34 | struct file *file = area->vm_file; | |
92e5baef | 35 | struct dentry *dentry = file->f_path.dentry; |
1da177e4 | 36 | struct inode *inode = dentry->d_inode; |
1da177e4 LT |
37 | char *pg_addr; |
38 | unsigned int already_read; | |
39 | unsigned int count; | |
40 | int bufsize; | |
d0217ac0 | 41 | int pos; /* XXX: loff_t ? */ |
1da177e4 | 42 | |
d0217ac0 NP |
43 | /* |
44 | * ncpfs has nothing against high pages as long | |
45 | * as recvmsg and memset works on it | |
46 | */ | |
47 | vmf->page = alloc_page(GFP_HIGHUSER); | |
48 | if (!vmf->page) | |
49 | return VM_FAULT_OOM; | |
50 | pg_addr = kmap(vmf->page); | |
51 | pos = vmf->pgoff << PAGE_SHIFT; | |
1da177e4 LT |
52 | |
53 | count = PAGE_SIZE; | |
1da177e4 LT |
54 | /* what we can read in one go */ |
55 | bufsize = NCP_SERVER(inode)->buffer_size; | |
56 | ||
57 | already_read = 0; | |
58 | if (ncp_make_open(inode, O_RDONLY) >= 0) { | |
59 | while (already_read < count) { | |
60 | int read_this_time; | |
61 | int to_read; | |
62 | ||
63 | to_read = bufsize - (pos % bufsize); | |
64 | ||
65 | to_read = min_t(unsigned int, to_read, count - already_read); | |
66 | ||
67 | if (ncp_read_kernel(NCP_SERVER(inode), | |
68 | NCP_FINFO(inode)->file_handle, | |
69 | pos, to_read, | |
70 | pg_addr + already_read, | |
71 | &read_this_time) != 0) { | |
72 | read_this_time = 0; | |
73 | } | |
74 | pos += read_this_time; | |
75 | already_read += read_this_time; | |
76 | ||
77 | if (read_this_time < to_read) { | |
78 | break; | |
79 | } | |
80 | } | |
81 | ncp_inode_close(inode); | |
82 | ||
83 | } | |
84 | ||
85 | if (already_read < PAGE_SIZE) | |
86 | memset(pg_addr + already_read, 0, PAGE_SIZE - already_read); | |
d0217ac0 NP |
87 | flush_dcache_page(vmf->page); |
88 | kunmap(vmf->page); | |
1da177e4 LT |
89 | |
90 | /* | |
91 | * If I understand ncp_read_kernel() properly, the above always | |
92 | * fetches from the network, here the analogue of disk. | |
93 | * -- wli | |
94 | */ | |
f8891e5e | 95 | count_vm_event(PGMAJFAULT); |
456f998e | 96 | mem_cgroup_count_vm_event(area->vm_mm, PGMAJFAULT); |
d0217ac0 | 97 | return VM_FAULT_MAJOR; |
1da177e4 LT |
98 | } |
99 | ||
f0f37e2f | 100 | static const struct vm_operations_struct ncp_file_mmap = |
1da177e4 | 101 | { |
54cb8821 | 102 | .fault = ncp_file_mmap_fault, |
1da177e4 LT |
103 | }; |
104 | ||
105 | ||
106 | /* This is used for a general mmap of a ncp file */ | |
107 | int ncp_mmap(struct file *file, struct vm_area_struct *vma) | |
108 | { | |
92e5baef | 109 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
110 | |
111 | DPRINTK("ncp_mmap: called\n"); | |
112 | ||
113 | if (!ncp_conn_valid(NCP_SERVER(inode))) | |
114 | return -EIO; | |
115 | ||
116 | /* only PAGE_COW or read-only supported now */ | |
117 | if (vma->vm_flags & VM_SHARED) | |
118 | return -EINVAL; | |
119 | /* we do not support files bigger than 4GB... We eventually | |
120 | supports just 4GB... */ | |
121 | if (((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff | |
122 | > (1U << (32 - PAGE_SHIFT))) | |
123 | return -EFBIG; | |
124 | ||
125 | vma->vm_ops = &ncp_file_mmap; | |
126 | file_accessed(file); | |
127 | return 0; | |
128 | } |