1 // SPDX-License-Identifier: GPL-2.0-only
5  * produce the same thing and, for cases where a k-bit hash
8  * We fill a buffer with a 255-byte null-terminated string,
9  * and use both full_name_hash() and hashlen_string() to hash the
10  * substrings from i to j, where 0 <= i < j < 256.
12  * The returned values are used to check that __hash_32() and
26 /* 32-bit XORSHIFT generator.  Seed must not be zero. */
36 /* Given a non-zero x, returns a non-zero byte. */
47 /* Fill the buffer with non-zero bytes. */
60  * Test the various integer hash functions.  h64 (or its low-order bits)
61  * is the integer to hash.  hash_or accumulates the OR of the hash values,
62  * which are later checked to see that they cover all the requested bits.
64  * Because these functions (as opposed to the string hashes) are all
66  * recompile and re-test the module without rebooting.
71 	int k;  in test_int_hash()  local
87 	/* Test k = 1..32 bits */  in test_int_hash()
88 	for (k = 1; k <= 32; k++) {  in test_int_hash()
89 		u32 const m = ((u32)2 << (k-1)) - 1;	/* Low k bits set */  in test_int_hash()
92 		hash_or[0][k] |= h1 = hash_32(h0, k);  in test_int_hash()
94 			pr_err("hash_32(%#x, %d) = %#x > %#x", h0, k, h1, m);  in test_int_hash()
98 		h2 = hash_32_generic(h0, k);  in test_int_hash()
102 				" = %#x", h0, k, h1, h2);  in test_int_hash()
108 				h0, k, h1, m);  in test_int_hash()
114 		hash_or[1][k] |= h1 = hash_64(h64, k);  in test_int_hash()
116 			pr_err("hash_64(%#llx, %d) = %#x > %#x", h64, k, h1, m);  in test_int_hash()
120 		h2 = hash_64_generic(h64, k);  in test_int_hash()
124 				"= %#x", h64, k, h1, h2);  in test_int_hash()
130 				h64, k, h1, m);  in test_int_hash()
150 	int i, j;  in test_hash_init()  local
154 	/* Test every possible non-empty substring in the buffer. */  in test_hash_init()
155 	for (j = SIZE; j > 0; --j) {  in test_hash_init()
156 		buf[j] = '\0';  in test_hash_init()
158 		for (i = 0; i <= j; i++) {  in test_hash_init()
160 			u32 h0 = full_name_hash(buf+i, buf+i, j-i);  in test_hash_init()
163 			if (hashlen_len(hashlen) != j-i) {  in test_hash_init()
166 					i, j, hashlen_len(hashlen), j-i);  in test_hash_init()
167 				return -EINVAL;  in test_hash_init()
173 					i, j, hashlen_hash(hashlen), h0);  in test_hash_init()
174 				return -EINVAL;  in test_hash_init()
180 				return -EINVAL;  in test_hash_init()
183 	} /* j */  in test_hash_init()
188 			string_or, -1u);  in test_hash_init()
189 		return -EINVAL;  in test_hash_init()
193 			hash_or[0][0], -1u);  in test_hash_init()
194 		return -EINVAL;  in test_hash_init()
200 			hash_or[1][0], -1u);  in test_hash_init()
201 		return -EINVAL;  in test_hash_init()
206 	/* Likewise for all the i-bit hash values */  in test_hash_init()
208 		u32 const m = ((u32)2 << (i-1)) - 1;	/* Low i bits set */  in test_hash_init()
213 			return -EINVAL;  in test_hash_init()
218 			return -EINVAL;  in test_hash_init()
225 	pr_info("__hash_32() is arch-specific; not compared to generic.");  in test_hash_init()
228 	pr_info("__hash_32() has no arch implementation to test.");  in test_hash_init()
232 	pr_info("hash_32() is arch-specific; not compared to generic.");  in test_hash_init()
235 	pr_info("hash_32() has no arch implementation to test.");  in test_hash_init()
239 	pr_info("hash_64() is arch-specific; not compared to generic.");  in test_hash_init()
242 	pr_info("hash_64() has no arch implementation to test.");  in test_hash_init()