1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Ceph cache definitions.
4  *
5  *  Copyright (C) 2013 by Adfin Solutions, Inc. All Rights Reserved.
6  *  Written by Milosz Tanski (milosz@adfin.com)
7  */
8 
9 #include <linux/ceph/ceph_debug.h>
10 
11 #include <linux/fs_context.h>
12 #include "super.h"
13 #include "cache.h"
14 
ceph_fscache_register_inode_cookie(struct inode * inode)15 void ceph_fscache_register_inode_cookie(struct inode *inode)
16 {
17 	struct ceph_inode_info *ci = ceph_inode(inode);
18 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
19 
20 	/* No caching for filesystem? */
21 	if (!fsc->fscache)
22 		return;
23 
24 	/* Regular files only */
25 	if (!S_ISREG(inode->i_mode))
26 		return;
27 
28 	/* Only new inodes! */
29 	if (!(inode->i_state & I_NEW))
30 		return;
31 
32 	WARN_ON_ONCE(ci->netfs.cache);
33 
34 	ci->netfs.cache =
35 		fscache_acquire_cookie(fsc->fscache, 0,
36 				       &ci->i_vino, sizeof(ci->i_vino),
37 				       &ci->i_version, sizeof(ci->i_version),
38 				       i_size_read(inode));
39 	if (ci->netfs.cache)
40 		mapping_set_release_always(inode->i_mapping);
41 }
42 
ceph_fscache_unregister_inode_cookie(struct ceph_inode_info * ci)43 void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info *ci)
44 {
45 	fscache_relinquish_cookie(ceph_fscache_cookie(ci), false);
46 }
47 
ceph_fscache_use_cookie(struct inode * inode,bool will_modify)48 void ceph_fscache_use_cookie(struct inode *inode, bool will_modify)
49 {
50 	struct ceph_inode_info *ci = ceph_inode(inode);
51 
52 	fscache_use_cookie(ceph_fscache_cookie(ci), will_modify);
53 }
54 
ceph_fscache_unuse_cookie(struct inode * inode,bool update)55 void ceph_fscache_unuse_cookie(struct inode *inode, bool update)
56 {
57 	struct ceph_inode_info *ci = ceph_inode(inode);
58 
59 	if (update) {
60 		loff_t i_size = i_size_read(inode);
61 
62 		fscache_unuse_cookie(ceph_fscache_cookie(ci),
63 				     &ci->i_version, &i_size);
64 	} else {
65 		fscache_unuse_cookie(ceph_fscache_cookie(ci), NULL, NULL);
66 	}
67 }
68 
ceph_fscache_update(struct inode * inode)69 void ceph_fscache_update(struct inode *inode)
70 {
71 	struct ceph_inode_info *ci = ceph_inode(inode);
72 	loff_t i_size = i_size_read(inode);
73 
74 	fscache_update_cookie(ceph_fscache_cookie(ci), &ci->i_version, &i_size);
75 }
76 
ceph_fscache_invalidate(struct inode * inode,bool dio_write)77 void ceph_fscache_invalidate(struct inode *inode, bool dio_write)
78 {
79 	struct ceph_inode_info *ci = ceph_inode(inode);
80 
81 	fscache_invalidate(ceph_fscache_cookie(ci),
82 			   &ci->i_version, i_size_read(inode),
83 			   dio_write ? FSCACHE_INVAL_DIO_WRITE : 0);
84 }
85 
ceph_fscache_register_fs(struct ceph_fs_client * fsc,struct fs_context * fc)86 int ceph_fscache_register_fs(struct ceph_fs_client* fsc, struct fs_context *fc)
87 {
88 	const struct ceph_fsid *fsid = &fsc->client->fsid;
89 	const char *fscache_uniq = fsc->mount_options->fscache_uniq;
90 	size_t uniq_len = fscache_uniq ? strlen(fscache_uniq) : 0;
91 	char *name;
92 	int err = 0;
93 
94 	name = kasprintf(GFP_KERNEL, "ceph,%pU%s%s", fsid, uniq_len ? "," : "",
95 			 uniq_len ? fscache_uniq : "");
96 	if (!name)
97 		return -ENOMEM;
98 
99 	fsc->fscache = fscache_acquire_volume(name, NULL, NULL, 0);
100 	if (IS_ERR_OR_NULL(fsc->fscache)) {
101 		errorfc(fc, "Unable to register fscache cookie for %s", name);
102 		err = fsc->fscache ? PTR_ERR(fsc->fscache) : -EOPNOTSUPP;
103 		fsc->fscache = NULL;
104 	}
105 	kfree(name);
106 	return err;
107 }
108 
ceph_fscache_unregister_fs(struct ceph_fs_client * fsc)109 void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
110 {
111 	fscache_relinquish_volume(fsc->fscache, NULL, false);
112 }
113