1 /*
2  * Copyright (c) 2017-2019, Intel Corporation
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  *  * Redistributions of source code must retain the above copyright notice,
8  *    this list of conditions and the following disclaimer.
9  *  * Redistributions in binary form must reproduce the above copyright notice,
10  *    this list of conditions and the following disclaimer in the documentation
11  *    and/or other materials provided with the distribution.
12  *  * Neither the name of Intel Corporation nor the names of its contributors
13  *    may be used to endorse or promote products derived from this software
14  *    without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef PT_MSEC_CACHE_H
30 #define PT_MSEC_CACHE_H
31 
32 #include "pt_mapped_section.h"
33 
34 #include "intel-pt.h"
35 
36 
37 /* A single-entry mapped section cache.
38  *
39  * The cached section is implicitly mapped and unmapped.  The cache is not
40  * thread-safe.
41  */
42 struct pt_msec_cache {
43 	/* The cached section.
44 	 *
45 	 * The cache is valid if and only if @msec.section is not NULL.
46 	 *
47 	 * It needs to be unmapped and put.  Use pt_blk_scache_invalidate() to
48 	 * release the cached section and to invalidate the cache.
49 	 */
50 	struct pt_mapped_section msec;
51 
52 	/* The section identifier. */
53 	int isid;
54 };
55 
56 /* Initialize the cache. */
57 extern int pt_msec_cache_init(struct pt_msec_cache *cache);
58 
59 /* Finalize the cache. */
60 extern void pt_msec_cache_fini(struct pt_msec_cache *cache);
61 
62 /* Invalidate the cache. */
63 extern int pt_msec_cache_invalidate(struct pt_msec_cache *cache);
64 
65 /* Read the cached section.
66  *
67  * If @cache is not empty and @image would find it when looking up @vaddr in
68  * @*pmsec->asid, provide a pointer to the cached section in @pmsec and return
69  * its image section identifier.
70  *
71  * The provided pointer remains valid until @cache is invalidated.
72  *
73  * Returns @*pmsec's isid on success, a negative pt_error_code otherwise.
74  */
75 extern int pt_msec_cache_read(struct pt_msec_cache *cache,
76 			      const struct pt_mapped_section **pmsec,
77 			      struct pt_image *image, uint64_t vaddr);
78 
79 /* Fill the cache.
80  *
81  * Look up @vaddr in @asid in @image and cache as well as provide the found
82  * section in @pmsec and return its image section identifier.
83  *
84  * Invalidates @cache.
85  *
86  * The provided pointer remains valid until @cache is invalidated.
87  *
88  * Returns @*pmsec's isid on success, a negative pt_error_code otherwise.
89  */
90 extern int pt_msec_cache_fill(struct pt_msec_cache *cache,
91 			      const struct pt_mapped_section **pmsec,
92 			      struct pt_image *image,
93 			      const struct pt_asid *asid, uint64_t vaddr);
94 
95 #endif /* PT_MSEC_CACHE_H */
96