1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * V9FS cache definitions.
4 *
5 * Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
6 */
7
8#include <linux/jiffies.h>
9#include <linux/file.h>
10#include <linux/slab.h>
11#include <linux/stat.h>
12#include <linux/sched.h>
13#include <linux/fs.h>
14#include <net/9p/9p.h>
15
16#include "v9fs.h"
17#include "cache.h"
18
19int v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses,
20 const char *dev_name)
21{
22 struct fscache_volume *vcookie;
23 char *name, *p;
24
25 name = kasprintf(GFP_KERNEL, fmt: "9p,%s,%s",
26 dev_name, v9ses->cachetag ?: v9ses->aname);
27 if (!name)
28 return -ENOMEM;
29
30 for (p = name; *p; p++)
31 if (*p == '/')
32 *p = ';';
33
34 vcookie = fscache_acquire_volume(volume_key: name, NULL, NULL, coherency_len: 0);
35 p9_debug(P9_DEBUG_FSC, "session %p get volume %p (%s)\n",
36 v9ses, vcookie, name);
37 if (IS_ERR(ptr: vcookie)) {
38 if (vcookie != ERR_PTR(error: -EBUSY)) {
39 kfree(objp: name);
40 return PTR_ERR(ptr: vcookie);
41 }
42 pr_err("Cache volume key already in use (%s)\n", name);
43 vcookie = NULL;
44 }
45 v9ses->fscache = vcookie;
46 kfree(objp: name);
47 return 0;
48}
49
50void v9fs_cache_inode_get_cookie(struct inode *inode)
51{
52 struct v9fs_inode *v9inode = V9FS_I(inode);
53 struct v9fs_session_info *v9ses;
54 __le32 version;
55 __le64 path;
56
57 if (!S_ISREG(inode->i_mode))
58 return;
59 if (WARN_ON(v9fs_inode_cookie(v9inode)))
60 return;
61
62 version = cpu_to_le32(v9inode->qid.version);
63 path = cpu_to_le64(v9inode->qid.path);
64 v9ses = v9fs_inode2v9ses(inode);
65 v9inode->netfs.cache =
66 fscache_acquire_cookie(volume: v9fs_session_cache(v9ses),
67 advice: 0,
68 index_key: &path, index_key_len: sizeof(path),
69 aux_data: &version, aux_data_len: sizeof(version),
70 object_size: i_size_read(inode: &v9inode->netfs.inode));
71 if (v9inode->netfs.cache)
72 mapping_set_release_always(mapping: inode->i_mapping);
73
74 p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
75 inode, v9fs_inode_cookie(v9inode));
76}
77

source code of linux/fs/9p/cache.c