x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / fs / ncpfs / mmap.c
blob0c3905e0542e8902f5d988a0fe89491a378cbe51
1 /*
2 * mmap.c
4 * Copyright (C) 1995, 1996 by Volker Lendecke
5 * Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
7 */
9 #include <linux/stat.h>
10 #include <linux/time.h>
11 #include <linux/kernel.h>
12 #include <linux/gfp.h>
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>
18 #include <linux/fcntl.h>
19 #include <linux/memcontrol.h>
21 #include <linux/uaccess.h>
23 #include "ncp_fs.h"
26 * Fill in the supplied page for mmap
27 * XXX: how are we excluding truncate/invalidate here? Maybe need to lock
28 * page?
30 static int ncp_file_mmap_fault(struct vm_fault *vmf)
32 struct inode *inode = file_inode(vmf->vma->vm_file);
33 char *pg_addr;
34 unsigned int already_read;
35 unsigned int count;
36 int bufsize;
37 int pos; /* XXX: loff_t ? */
40 * ncpfs has nothing against high pages as long
41 * as recvmsg and memset works on it
43 vmf->page = alloc_page(GFP_HIGHUSER);
44 if (!vmf->page)
45 return VM_FAULT_OOM;
46 pg_addr = kmap(vmf->page);
47 pos = vmf->pgoff << PAGE_SHIFT;
49 count = PAGE_SIZE;
50 /* what we can read in one go */
51 bufsize = NCP_SERVER(inode)->buffer_size;
53 already_read = 0;
54 if (ncp_make_open(inode, O_RDONLY) >= 0) {
55 while (already_read < count) {
56 int read_this_time;
57 int to_read;
59 to_read = bufsize - (pos % bufsize);
61 to_read = min_t(unsigned int, to_read, count - already_read);
63 if (ncp_read_kernel(NCP_SERVER(inode),
64 NCP_FINFO(inode)->file_handle,
65 pos, to_read,
66 pg_addr + already_read,
67 &read_this_time) != 0) {
68 read_this_time = 0;
70 pos += read_this_time;
71 already_read += read_this_time;
73 if (read_this_time < to_read) {
74 break;
77 ncp_inode_close(inode);
81 if (already_read < PAGE_SIZE)
82 memset(pg_addr + already_read, 0, PAGE_SIZE - already_read);
83 flush_dcache_page(vmf->page);
84 kunmap(vmf->page);
87 * If I understand ncp_read_kernel() properly, the above always
88 * fetches from the network, here the analogue of disk.
89 * -- nyc
91 count_vm_event(PGMAJFAULT);
92 mem_cgroup_count_vm_event(vmf->vma->vm_mm, PGMAJFAULT);
93 return VM_FAULT_MAJOR;
96 static const struct vm_operations_struct ncp_file_mmap =
98 .fault = ncp_file_mmap_fault,
102 /* This is used for a general mmap of a ncp file */
103 int ncp_mmap(struct file *file, struct vm_area_struct *vma)
105 struct inode *inode = file_inode(file);
107 ncp_dbg(1, "called\n");
109 if (!ncp_conn_valid(NCP_SERVER(inode)))
110 return -EIO;
112 /* only PAGE_COW or read-only supported now */
113 if (vma->vm_flags & VM_SHARED)
114 return -EINVAL;
115 /* we do not support files bigger than 4GB... We eventually
116 supports just 4GB... */
117 if (vma_pages(vma) + vma->vm_pgoff
118 > (1U << (32 - PAGE_SHIFT)))
119 return -EFBIG;
121 vma->vm_ops = &ncp_file_mmap;
122 file_accessed(file);
123 return 0;