diff options
Diffstat (limited to 'drivers/staging/lustre/lustre/include/obd_cksum.h')
| -rw-r--r-- | drivers/staging/lustre/lustre/include/obd_cksum.h | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/staging/lustre/lustre/include/obd_cksum.h b/drivers/staging/lustre/lustre/include/obd_cksum.h new file mode 100644 index 000000000000..5f740f1743ca --- /dev/null +++ b/drivers/staging/lustre/lustre/include/obd_cksum.h @@ -0,0 +1,176 @@ +/* + * GPL HEADER START + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. + */ + +#ifndef __OBD_CKSUM +#define __OBD_CKSUM +#include <linux/libcfs/libcfs.h> +#include <lustre/lustre_idl.h> + +static inline unsigned char cksum_obd2cfs(cksum_type_t cksum_type) +{ + switch (cksum_type) { + case OBD_CKSUM_CRC32: + return CFS_HASH_ALG_CRC32; + case OBD_CKSUM_ADLER: + return CFS_HASH_ALG_ADLER32; + case OBD_CKSUM_CRC32C: + return CFS_HASH_ALG_CRC32C; + default: + CERROR("Unknown checksum type (%x)!!!\n", cksum_type); + LBUG(); + } + return 0; +} + +/* The OBD_FL_CKSUM_* flags is packed into 5 bits of o_flags, since there can + * only be a single checksum type per RPC. + * + * The OBD_CHECKSUM_* type bits passed in ocd_cksum_types are a 32-bit bitmask + * since they need to represent the full range of checksum algorithms that + * both the client and server can understand. + * + * In case of an unsupported types/flags we fall back to ADLER + * because that is supported by all clients since 1.8 + * + * In case multiple algorithms are supported the best one is used. */ +static inline obd_flag cksum_type_pack(cksum_type_t cksum_type) +{ + unsigned int performance = 0, tmp; + obd_flag flag = OBD_FL_CKSUM_ADLER; + + if (cksum_type & OBD_CKSUM_CRC32) { + tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)); + if (tmp > performance) { + performance = tmp; + flag = OBD_FL_CKSUM_CRC32; + } + } + if (cksum_type & OBD_CKSUM_CRC32C) { + tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)); + if (tmp > performance) { + performance = tmp; + flag = OBD_FL_CKSUM_CRC32C; + } + } + if (cksum_type & OBD_CKSUM_ADLER) { + tmp = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER)); + if (tmp > performance) { + performance = tmp; + flag = OBD_FL_CKSUM_ADLER; + } + } + if (unlikely(cksum_type && !(cksum_type & (OBD_CKSUM_CRC32C | + OBD_CKSUM_CRC32 | + OBD_CKSUM_ADLER)))) + CWARN("unknown cksum type %x\n", cksum_type); + + return flag; +} + +static inline cksum_type_t cksum_type_unpack(obd_flag o_flags) +{ + switch (o_flags & OBD_FL_CKSUM_ALL) { + case OBD_FL_CKSUM_CRC32C: + return OBD_CKSUM_CRC32C; + case OBD_FL_CKSUM_CRC32: + return OBD_CKSUM_CRC32; + default: + break; + } + + return OBD_CKSUM_ADLER; +} + +/* Return a bitmask of the checksum types supported on this system. + * 1.8 supported ADLER it is base and not depend on hw + * Client uses all available local algos + */ +static inline cksum_type_t cksum_types_supported_client(void) +{ + cksum_type_t ret = OBD_CKSUM_ADLER; + + CDEBUG(D_INFO, "Crypto hash speed: crc %d, crc32c %d, adler %d\n", + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)), + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)), + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER))); + + if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)) > 0) + ret |= OBD_CKSUM_CRC32C; + if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)) > 0) + ret |= OBD_CKSUM_CRC32; + + return ret; +} + +/* Server uses algos that perform at 50% or better of the Adler */ +static inline cksum_type_t cksum_types_supported_server(void) +{ + int base_speed; + cksum_type_t ret = OBD_CKSUM_ADLER; + + CDEBUG(D_INFO, "Crypto hash speed: crc %d, crc32c %d, adler %d\n", + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)), + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)), + cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER))); + + base_speed = cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_ADLER)) / 2; + + if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32C)) >= + base_speed) + ret |= OBD_CKSUM_CRC32C; + if (cfs_crypto_hash_speed(cksum_obd2cfs(OBD_CKSUM_CRC32)) >= + base_speed) + ret |= OBD_CKSUM_CRC32; + + return ret; +} + + +/* Select the best checksum algorithm among those supplied in the cksum_types + * input. + * + * Currently, calling cksum_type_pack() with a mask will return the fastest + * checksum type due to its benchmarking at libcfs module load. + * Caution is advised, however, since what is fastest on a single client may + * not be the fastest or most efficient algorithm on the server. */ +static inline cksum_type_t cksum_type_select(cksum_type_t cksum_types) +{ + return cksum_type_unpack(cksum_type_pack(cksum_types)); +} + +/* Checksum algorithm names. Must be defined in the same order as the + * OBD_CKSUM_* flags. */ +#define DECLARE_CKSUM_NAME char *cksum_name[] = {"crc32", "adler", "crc32c"} + +#endif /* __OBD_H */ |