lustre/obdclass/obd_cksum.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2018, DataDirect Networks Storage.
  24  * Author: Li Xi.
  25  *
  26  * Checksum functions
  27  */
  28 #include <obd_class.h>
  29 #include <obd_cksum.h>
  30
  31 /* Server uses algos that perform at 50% or better of the Adler */
  32 enum cksum_types obd_cksum_types_supported_server(const char *obd_name)
  33 {
  34         enum cksum_types ret = OBD_CKSUM_ADLER;
  35         int base_speed;
  36
  37         CDEBUG(D_INFO, "%s: checksum speed: crc %d, crc32c %d, adler %d, "
  38                "t10ip512 %d, t10ip4k %d, t10crc512 %d, t10crc4k %d\n",
  39                obd_name,
  40                cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)),
  41                cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)),
  42                cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER)),
  43                obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP512),
  44                obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP4K),
  45                obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC512),
  46                obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC4K));
  47
  48         base_speed = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER)) / 2;
  49
  50         if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)) >=
  51             base_speed)
  52                 ret |= OBD_CKSUM_CRC32C;
  53
  54         if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)) >=
  55             base_speed)
  56                 ret |= OBD_CKSUM_CRC32;
  57
  58         if (obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP512) >= base_speed)
  59                 ret |= OBD_CKSUM_T10IP512;
  60
  61         if (obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP4K) >= base_speed)
  62                 ret |= OBD_CKSUM_T10IP4K;
  63
  64         if (obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC512) >= base_speed)
  65                 ret |= OBD_CKSUM_T10CRC512;
  66
  67         if (obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC4K) >= base_speed)
  68                 ret |= OBD_CKSUM_T10CRC4K;
  69
  70         return ret;
  71 }
  72 EXPORT_SYMBOL(obd_cksum_types_supported_server);
  73
  74 /* The OBD_FL_CKSUM_* flags is packed into 5 bits of o_flags, since there can
  75  * only be a single checksum type per RPC.
  76  *
  77  * The OBD_CKSUM_* type bits passed in ocd_cksum_types are a 32-bit bitmask
  78  * since they need to represent the full range of checksum algorithms that
  79  * both the client and server can understand.
  80  *
  81  * In case of an unsupported types/flags we fall back to ADLER
  82  * because that is supported by all clients since 1.8
  83  *
  84  * In case multiple algorithms are supported the best one is used. */
  85 u32 obd_cksum_type_pack(const char *obd_name, enum cksum_types cksum_type)
  86 {
  87         unsigned int performance = 0, tmp;
  88         u32 flag = OBD_FL_CKSUM_ADLER;
  89
  90         if (cksum_type & OBD_CKSUM_CRC32) {
  91                 tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32));
  92                 if (tmp > performance) {
  93                         performance = tmp;
  94                         flag = OBD_FL_CKSUM_CRC32;
  95                 }
  96         }
  97         if (cksum_type & OBD_CKSUM_CRC32C) {
  98                 tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C));
  99                 if (tmp > performance) {
 100                         performance = tmp;
 101                         flag = OBD_FL_CKSUM_CRC32C;
 102                 }
 103         }
 104         if (cksum_type & OBD_CKSUM_ADLER) {
 105                 tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER));
 106                 if (tmp > performance) {
 107                         performance = tmp;
 108                         flag = OBD_FL_CKSUM_ADLER;
 109                 }
 110         }
 111
 112         if (cksum_type & OBD_CKSUM_T10IP512) {
 113                 tmp = obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP512);
 114                 if (tmp > performance) {
 115                         performance = tmp;
 116                         flag = OBD_FL_CKSUM_T10IP512;
 117                 }
 118         }
 119
 120         if (cksum_type & OBD_CKSUM_T10IP4K) {
 121                 tmp = obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10IP4K);
 122                 if (tmp > performance) {
 123                         performance = tmp;
 124                         flag = OBD_FL_CKSUM_T10IP4K;
 125                 }
 126         }
 127
 128         if (cksum_type & OBD_CKSUM_T10CRC512) {
 129                 tmp = obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC512);
 130                 if (tmp > performance) {
 131                         performance = tmp;
 132                         flag = OBD_FL_CKSUM_T10CRC512;
 133                 }
 134         }
 135
 136         if (cksum_type & OBD_CKSUM_T10CRC4K) {
 137                 tmp = obd_t10_cksum_speed(obd_name, OBD_CKSUM_T10CRC4K);
 138                 if (tmp > performance) {
 139                         performance = tmp;
 140                         flag = OBD_FL_CKSUM_T10CRC4K;
 141                 }
 142         }
 143
 144         if (unlikely(cksum_type && !(cksum_type & OBD_CKSUM_ALL)))
 145                 CWARN("%s: unknown cksum type %x\n", obd_name, cksum_type);
 146
 147         return flag;
 148 }
 149 EXPORT_SYMBOL(obd_cksum_type_pack);