1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright 2023 Red Hat
4 */
5
6 #ifndef UDS_INDEX_SESSION_H
7 #define UDS_INDEX_SESSION_H
8
9 #include <linux/atomic.h>
10 #include <linux/cache.h>
11
12 #include "thread-utils.h"
13
14 #include "config.h"
15 #include "indexer.h"
16
17 /*
18 * The index session mediates all interactions with a UDS index. Once the index session is created,
19 * it can be used to open, close, suspend, or recreate an index. It implements the majority of the
20 * functions in the top-level UDS API.
21 *
22 * If any deduplication request fails due to an internal error, the index is marked disabled. It
23 * will not accept any further requests and can only be closed. Closing the index will clear the
24 * disabled flag, and the index can then be reopened and recovered using the same index session.
25 */
26
__aligned(L1_CACHE_BYTES)27 struct __aligned(L1_CACHE_BYTES) session_stats {
28 /* Post requests that found an entry */
29 u64 posts_found;
30 /* Post requests found in the open chapter */
31 u64 posts_found_open_chapter;
32 /* Post requests found in the dense index */
33 u64 posts_found_dense;
34 /* Post requests found in the sparse index */
35 u64 posts_found_sparse;
36 /* Post requests that did not find an entry */
37 u64 posts_not_found;
38 /* Update requests that found an entry */
39 u64 updates_found;
40 /* Update requests that did not find an entry */
41 u64 updates_not_found;
42 /* Delete requests that found an entry */
43 u64 deletions_found;
44 /* Delete requests that did not find an entry */
45 u64 deletions_not_found;
46 /* Query requests that found an entry */
47 u64 queries_found;
48 /* Query requests that did not find an entry */
49 u64 queries_not_found;
50 /* Total number of requests */
51 u64 requests;
52 };
53
54 enum index_suspend_status {
55 /* An index load has started but the index is not ready for use. */
56 INDEX_OPENING = 0,
57 /* The index is able to handle requests. */
58 INDEX_READY,
59 /* The index is attempting to suspend a rebuild. */
60 INDEX_SUSPENDING,
61 /* An index rebuild has been suspended. */
62 INDEX_SUSPENDED,
63 /* An index rebuild is being stopped in order to shut down. */
64 INDEX_FREEING,
65 };
66
67 struct index_load_context {
68 struct mutex mutex;
69 struct cond_var cond;
70 enum index_suspend_status status;
71 };
72
73 struct uds_index_session {
74 unsigned int state;
75 struct uds_index *index;
76 struct uds_request_queue *callback_queue;
77 struct uds_parameters parameters;
78 struct index_load_context load_context;
79 struct mutex request_mutex;
80 struct cond_var request_cond;
81 int request_count;
82 struct session_stats stats;
83 };
84
85 #endif /* UDS_INDEX_SESSION_H */
86