Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/fs/nfs/symlink.c | |
3 | * | |
4 | * Copyright (C) 1992 Rick Sladkey | |
5 | * | |
6 | * Optimization changes Copyright (C) 1994 Florian La Roche | |
7 | * | |
8 | * Jun 7 1999, cache symlink lookups in the page cache. -DaveM | |
9 | * | |
10 | * nfs symlink handling code | |
11 | */ | |
12 | ||
1da177e4 LT |
13 | #include <linux/time.h> |
14 | #include <linux/errno.h> | |
15 | #include <linux/sunrpc/clnt.h> | |
16 | #include <linux/nfs.h> | |
17 | #include <linux/nfs2.h> | |
18 | #include <linux/nfs_fs.h> | |
19 | #include <linux/pagemap.h> | |
20 | #include <linux/stat.h> | |
21 | #include <linux/mm.h> | |
22 | #include <linux/slab.h> | |
23 | #include <linux/string.h> | |
1da177e4 LT |
24 | #include <linux/namei.h> |
25 | ||
26 | /* Symlink caching in the page cache is even more simplistic | |
27 | * and straight-forward than readdir caching. | |
1da177e4 LT |
28 | */ |
29 | ||
1da177e4 LT |
30 | static int nfs_symlink_filler(struct inode *inode, struct page *page) |
31 | { | |
1da177e4 LT |
32 | int error; |
33 | ||
cc314eef | 34 | error = NFS_PROTO(inode)->readlink(inode, page, 0, PAGE_SIZE); |
1da177e4 LT |
35 | if (error < 0) |
36 | goto error; | |
37 | SetPageUptodate(page); | |
38 | unlock_page(page); | |
39 | return 0; | |
40 | ||
41 | error: | |
42 | SetPageError(page); | |
43 | unlock_page(page); | |
44 | return -EIO; | |
45 | } | |
46 | ||
cc314eef | 47 | static void *nfs_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
48 | { |
49 | struct inode *inode = dentry->d_inode; | |
50 | struct page *page; | |
717d44e8 TM |
51 | void *err; |
52 | ||
53 | err = ERR_PTR(nfs_revalidate_mapping_nolock(inode, inode->i_mapping)); | |
1da177e4 LT |
54 | if (err) |
55 | goto read_failed; | |
56 | page = read_cache_page(&inode->i_data, 0, | |
57 | (filler_t *)nfs_symlink_filler, inode); | |
58 | if (IS_ERR(page)) { | |
59 | err = page; | |
60 | goto read_failed; | |
61 | } | |
cc314eef LT |
62 | nd_set_link(nd, kmap(page)); |
63 | return page; | |
1da177e4 | 64 | |
1da177e4 LT |
65 | read_failed: |
66 | nd_set_link(nd, err); | |
cc314eef | 67 | return NULL; |
1da177e4 LT |
68 | } |
69 | ||
1da177e4 LT |
70 | /* |
71 | * symlinks can't do much... | |
72 | */ | |
92e1d5be | 73 | const struct inode_operations nfs_symlink_inode_operations = { |
1da177e4 LT |
74 | .readlink = generic_readlink, |
75 | .follow_link = nfs_follow_link, | |
9bf2aa12 | 76 | .put_link = page_put_link, |
1da177e4 LT |
77 | .getattr = nfs_getattr, |
78 | .setattr = nfs_setattr, | |
79 | }; |