1 #include <stdlib.h>
2 #include <assert.h>
3 
4 #include "fio.h"
5 #include "flist.h"
6 #include "hash.h"
7 #include "filehash.h"
8 #include "smalloc.h"
9 #include "lib/bloom.h"
10 
11 #define HASH_BUCKETS	512
12 #define HASH_MASK	(HASH_BUCKETS - 1)
13 
14 #define BLOOM_SIZE	16*1024*1024
15 
16 static unsigned int file_hash_size = HASH_BUCKETS * sizeof(struct flist_head);
17 
18 static struct flist_head *file_hash;
19 static struct fio_sem *hash_lock;
20 static struct bloom *file_bloom;
21 
hash(const char * name)22 static unsigned short hash(const char *name)
23 {
24 	return jhash(name, strlen(name), 0) & HASH_MASK;
25 }
26 
fio_file_hash_lock(void)27 void fio_file_hash_lock(void)
28 {
29 	if (hash_lock)
30 		fio_sem_down(hash_lock);
31 }
32 
fio_file_hash_unlock(void)33 void fio_file_hash_unlock(void)
34 {
35 	if (hash_lock)
36 		fio_sem_up(hash_lock);
37 }
38 
remove_file_hash(struct fio_file * f)39 void remove_file_hash(struct fio_file *f)
40 {
41 	fio_sem_down(hash_lock);
42 
43 	if (fio_file_hashed(f)) {
44 		assert(!flist_empty(&f->hash_list));
45 		flist_del_init(&f->hash_list);
46 		fio_file_clear_hashed(f);
47 	}
48 
49 	fio_sem_up(hash_lock);
50 }
51 
__lookup_file_hash(const char * name)52 static struct fio_file *__lookup_file_hash(const char *name)
53 {
54 	struct flist_head *bucket = &file_hash[hash(name)];
55 	struct flist_head *n;
56 
57 	flist_for_each(n, bucket) {
58 		struct fio_file *f = flist_entry(n, struct fio_file, hash_list);
59 
60 		if (!f->file_name)
61 			continue;
62 
63 		if (!strcmp(f->file_name, name))
64 			return f;
65 	}
66 
67 	return NULL;
68 }
69 
lookup_file_hash(const char * name)70 struct fio_file *lookup_file_hash(const char *name)
71 {
72 	struct fio_file *f;
73 
74 	fio_sem_down(hash_lock);
75 	f = __lookup_file_hash(name);
76 	fio_sem_up(hash_lock);
77 	return f;
78 }
79 
add_file_hash(struct fio_file * f)80 struct fio_file *add_file_hash(struct fio_file *f)
81 {
82 	struct fio_file *alias;
83 
84 	if (fio_file_hashed(f))
85 		return NULL;
86 
87 	INIT_FLIST_HEAD(&f->hash_list);
88 
89 	fio_sem_down(hash_lock);
90 
91 	alias = __lookup_file_hash(f->file_name);
92 	if (!alias) {
93 		fio_file_set_hashed(f);
94 		flist_add_tail(&f->hash_list, &file_hash[hash(f->file_name)]);
95 	}
96 
97 	fio_sem_up(hash_lock);
98 	return alias;
99 }
100 
file_bloom_exists(const char * fname,bool set)101 bool file_bloom_exists(const char *fname, bool set)
102 {
103 	return bloom_string(file_bloom, fname, strlen(fname), set);
104 }
105 
file_hash_exit(void)106 void file_hash_exit(void)
107 {
108 	unsigned int i, has_entries = 0;
109 
110 	fio_sem_down(hash_lock);
111 	for (i = 0; i < HASH_BUCKETS; i++)
112 		has_entries += !flist_empty(&file_hash[i]);
113 	fio_sem_up(hash_lock);
114 
115 	if (has_entries)
116 		log_err("fio: file hash not empty on exit\n");
117 
118 	sfree(file_hash);
119 	file_hash = NULL;
120 	fio_sem_remove(hash_lock);
121 	hash_lock = NULL;
122 	bloom_free(file_bloom);
123 	file_bloom = NULL;
124 }
125 
file_hash_init(void)126 void file_hash_init(void)
127 {
128 	unsigned int i;
129 
130 	file_hash = smalloc(file_hash_size);
131 
132 	for (i = 0; i < HASH_BUCKETS; i++)
133 		INIT_FLIST_HEAD(&file_hash[i]);
134 
135 	hash_lock = fio_sem_init(FIO_SEM_UNLOCKED);
136 	file_bloom = bloom_new(BLOOM_SIZE);
137 }
138