Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * mm/fadvise.c | |
3 | * | |
4 | * Copyright (C) 2002, Linus Torvalds | |
5 | * | |
e1f8e874 | 6 | * 11Jan2003 Andrew Morton |
1da177e4 LT |
7 | * Initial version. |
8 | */ | |
9 | ||
10 | #include <linux/kernel.h> | |
11 | #include <linux/file.h> | |
12 | #include <linux/fs.h> | |
13 | #include <linux/mm.h> | |
14 | #include <linux/pagemap.h> | |
15 | #include <linux/backing-dev.h> | |
16 | #include <linux/pagevec.h> | |
17 | #include <linux/fadvise.h> | |
ebcf28e1 | 18 | #include <linux/writeback.h> |
1da177e4 LT |
19 | #include <linux/syscalls.h> |
20 | ||
21 | #include <asm/unistd.h> | |
22 | ||
23 | /* | |
24 | * POSIX_FADV_WILLNEED could set PG_Referenced, and POSIX_FADV_NOREUSE could | |
25 | * deactivate the pages and clear PG_Referenced. | |
26 | */ | |
6673e0c3 | 27 | SYSCALL_DEFINE(fadvise64_64)(int fd, loff_t offset, loff_t len, int advice) |
1da177e4 | 28 | { |
61144378 AV |
29 | int fput_needed; |
30 | struct file *file = fget_light(fd, &fput_needed); | |
1da177e4 LT |
31 | struct address_space *mapping; |
32 | struct backing_dev_info *bdi; | |
ebcf28e1 | 33 | loff_t endbyte; /* inclusive */ |
1da177e4 LT |
34 | pgoff_t start_index; |
35 | pgoff_t end_index; | |
36 | unsigned long nrpages; | |
37 | int ret = 0; | |
38 | ||
39 | if (!file) | |
40 | return -EBADF; | |
41 | ||
d3ac7f89 | 42 | if (S_ISFIFO(file->f_path.dentry->d_inode->i_mode)) { |
87ba81db VB |
43 | ret = -ESPIPE; |
44 | goto out; | |
45 | } | |
46 | ||
1da177e4 LT |
47 | mapping = file->f_mapping; |
48 | if (!mapping || len < 0) { | |
49 | ret = -EINVAL; | |
50 | goto out; | |
51 | } | |
52 | ||
70688e4d | 53 | if (mapping->a_ops->get_xip_mem) { |
b5beb1ca MY |
54 | switch (advice) { |
55 | case POSIX_FADV_NORMAL: | |
56 | case POSIX_FADV_RANDOM: | |
57 | case POSIX_FADV_SEQUENTIAL: | |
58 | case POSIX_FADV_WILLNEED: | |
59 | case POSIX_FADV_NOREUSE: | |
60 | case POSIX_FADV_DONTNEED: | |
61 | /* no bad return value, but ignore advice */ | |
62 | break; | |
63 | default: | |
64 | ret = -EINVAL; | |
65 | } | |
fe77ba6f | 66 | goto out; |
b5beb1ca | 67 | } |
fe77ba6f | 68 | |
1da177e4 LT |
69 | /* Careful about overflows. Len == 0 means "as much as possible" */ |
70 | endbyte = offset + len; | |
71 | if (!len || endbyte < len) | |
72 | endbyte = -1; | |
ebcf28e1 AM |
73 | else |
74 | endbyte--; /* inclusive */ | |
1da177e4 LT |
75 | |
76 | bdi = mapping->backing_dev_info; | |
77 | ||
78 | switch (advice) { | |
79 | case POSIX_FADV_NORMAL: | |
80 | file->f_ra.ra_pages = bdi->ra_pages; | |
0141450f WF |
81 | spin_lock(&file->f_lock); |
82 | file->f_mode &= ~FMODE_RANDOM; | |
83 | spin_unlock(&file->f_lock); | |
1da177e4 LT |
84 | break; |
85 | case POSIX_FADV_RANDOM: | |
0141450f WF |
86 | spin_lock(&file->f_lock); |
87 | file->f_mode |= FMODE_RANDOM; | |
88 | spin_unlock(&file->f_lock); | |
1da177e4 LT |
89 | break; |
90 | case POSIX_FADV_SEQUENTIAL: | |
91 | file->f_ra.ra_pages = bdi->ra_pages * 2; | |
0141450f WF |
92 | spin_lock(&file->f_lock); |
93 | file->f_mode &= ~FMODE_RANDOM; | |
94 | spin_unlock(&file->f_lock); | |
1da177e4 LT |
95 | break; |
96 | case POSIX_FADV_WILLNEED: | |
1da177e4 LT |
97 | /* First and last PARTIAL page! */ |
98 | start_index = offset >> PAGE_CACHE_SHIFT; | |
ebcf28e1 | 99 | end_index = endbyte >> PAGE_CACHE_SHIFT; |
1da177e4 LT |
100 | |
101 | /* Careful about overflow on the "+1" */ | |
102 | nrpages = end_index - start_index + 1; | |
103 | if (!nrpages) | |
104 | nrpages = ~0UL; | |
3d3727cd KM |
105 | |
106 | /* | |
107 | * Ignore return value because fadvise() shall return | |
108 | * success even if filesystem can't retrieve a hint, | |
109 | */ | |
110 | force_page_cache_readahead(mapping, file, start_index, | |
111 | nrpages); | |
1da177e4 | 112 | break; |
60c371bc AM |
113 | case POSIX_FADV_NOREUSE: |
114 | break; | |
1da177e4 LT |
115 | case POSIX_FADV_DONTNEED: |
116 | if (!bdi_write_congested(mapping->backing_dev_info)) | |
ad8a1b55 SB |
117 | __filemap_fdatawrite_range(mapping, offset, endbyte, |
118 | WB_SYNC_NONE); | |
1da177e4 LT |
119 | |
120 | /* First and last FULL page! */ | |
ebcf28e1 | 121 | start_index = (offset+(PAGE_CACHE_SIZE-1)) >> PAGE_CACHE_SHIFT; |
1da177e4 LT |
122 | end_index = (endbyte >> PAGE_CACHE_SHIFT); |
123 | ||
ebcf28e1 AM |
124 | if (end_index >= start_index) |
125 | invalidate_mapping_pages(mapping, start_index, | |
126 | end_index); | |
127 | break; | |
1da177e4 LT |
128 | default: |
129 | ret = -EINVAL; | |
130 | } | |
131 | out: | |
61144378 | 132 | fput_light(file, fput_needed); |
1da177e4 LT |
133 | return ret; |
134 | } | |
6673e0c3 HC |
135 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
136 | asmlinkage long SyS_fadvise64_64(long fd, loff_t offset, loff_t len, long advice) | |
137 | { | |
138 | return SYSC_fadvise64_64((int) fd, offset, len, (int) advice); | |
139 | } | |
140 | SYSCALL_ALIAS(sys_fadvise64_64, SyS_fadvise64_64); | |
141 | #endif | |
1da177e4 LT |
142 | |
143 | #ifdef __ARCH_WANT_SYS_FADVISE64 | |
144 | ||
6673e0c3 | 145 | SYSCALL_DEFINE(fadvise64)(int fd, loff_t offset, size_t len, int advice) |
1da177e4 LT |
146 | { |
147 | return sys_fadvise64_64(fd, offset, len, advice); | |
148 | } | |
6673e0c3 HC |
149 | #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS |
150 | asmlinkage long SyS_fadvise64(long fd, loff_t offset, long len, long advice) | |
151 | { | |
152 | return SYSC_fadvise64((int) fd, offset, (size_t)len, (int)advice); | |
153 | } | |
154 | SYSCALL_ALIAS(sys_fadvise64, SyS_fadvise64); | |
155 | #endif | |
1da177e4 LT |
156 | |
157 | #endif |