]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blame - fs/nfs/symlink.c
Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[mirror_ubuntu-bionic-kernel.git] / fs / nfs / symlink.c
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1da177e4
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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
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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>
1da177e4 22#include <linux/string.h>
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23
24/* Symlink caching in the page cache is even more simplistic
25 * and straight-forward than readdir caching.
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26 */
27
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28static int nfs_symlink_filler(struct inode *inode, struct page *page)
29{
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30 int error;
31
cc314eef 32 error = NFS_PROTO(inode)->readlink(inode, page, 0, PAGE_SIZE);
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33 if (error < 0)
34 goto error;
35 SetPageUptodate(page);
36 unlock_page(page);
37 return 0;
38
39error:
40 SetPageError(page);
41 unlock_page(page);
42 return -EIO;
43}
44
6b255391 45static const char *nfs_get_link(struct dentry *dentry,
fceef393
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46 struct inode *inode,
47 struct delayed_call *done)
1da177e4 48{
1da177e4 49 struct page *page;
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50 void *err;
51
0d0def49
AV
52 if (!dentry) {
53 err = ERR_PTR(nfs_revalidate_mapping_rcu(inode));
54 if (err)
55 return err;
56 page = find_get_page(inode->i_mapping, 0);
57 if (!page)
58 return ERR_PTR(-ECHILD);
59 if (!PageUptodate(page)) {
60 put_page(page);
61 return ERR_PTR(-ECHILD);
62 }
63 } else {
64 err = ERR_PTR(nfs_revalidate_mapping(inode, inode->i_mapping));
65 if (err)
66 return err;
67 page = read_cache_page(&inode->i_data, 0,
68 (filler_t *)nfs_symlink_filler, inode);
69 if (IS_ERR(page))
70 return ERR_CAST(page);
71 }
fceef393 72 set_delayed_call(done, page_put_link, page);
21fc61c7 73 return page_address(page);
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74}
75
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76/*
77 * symlinks can't do much...
78 */
92e1d5be 79const struct inode_operations nfs_symlink_inode_operations = {
1da177e4 80 .readlink = generic_readlink,
6b255391 81 .get_link = nfs_get_link,
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82 .getattr = nfs_getattr,
83 .setattr = nfs_setattr,
84};