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LU-1201 checksum: add libcfs crypto hash
[fs/lustre-release.git] / lustre / include / obd_cksum.h
index 7166f7a..d546bb8 100644 (file)
 
 #ifndef __OBD_CKSUM
 #define __OBD_CKSUM
-
-#if defined(__linux__)
-#include <linux/obd_cksum.h>
-#elif defined(__APPLE__)
-#include <darwin/obd_chksum.h>
-#elif defined(__WINNT__)
-#include <winnt/obd_cksum.h>
-#else
-#error Unsupported operating system.
-#endif
-
+#include <libcfs/libcfs.h>
 #include <lustre/lustre_idl.h>
 
-/*
- * Checksums
- */
-
-#ifndef HAVE_ARCH_CRC32
-/* crc32_le lifted from the Linux kernel, which had the following to say:
- *
- * This code is in the public domain; copyright abandoned.
- * Liability for non-performance of this code is limited to the amount
- * you paid for it.  Since it is distributed for free, your refund will
- * be very very small.  If it breaks, you get to keep both pieces.
- */
-#define CRCPOLY_LE 0xedb88320
-/**
- * crc32_le() - Calculate bitwise little-endian Ethernet AUTODIN II CRC32
- * \param crc  seed value for computation.  ~0 for Ethernet, sometimes 0 for
- *             other uses, or the previous crc32 value if computing incrementally.
- * \param p  - pointer to buffer over which CRC is run
- * \param len- length of buffer \a p
- */
-static inline __u32 crc32_le(__u32 crc, unsigned char const *p, size_t len)
-{
-        int i;
-        while (len--) {
-                crc ^= *p++;
-                for (i = 0; i < 8; i++)
-                        crc = (crc >> 1) ^ ((crc & 1) ? CRCPOLY_LE : 0);
-        }
-        return crc;
-}
-#endif
-#ifdef HAVE_ADLER
-/* Adler-32 is supported */
-#define CHECKSUM_ADLER OBD_CKSUM_ADLER
-#else
-#define CHECKSUM_ADLER 0
-#endif
-
-#ifdef X86_FEATURE_XMM4_2
-/* Call Nehalem+ CRC32C harware acceleration instruction on individual bytes. */
-static inline __u32 crc32c_hw_byte(__u32 crc, unsigned char const *p,
-                                  size_t bytes)
+static inline unsigned char cksum_obd2cfs(cksum_type_t cksum_type)
 {
-        while (bytes--) {
-                __asm__ __volatile__ (
-                        ".byte 0xf2, 0xf, 0x38, 0xf0, 0xf1"
-                        : "=S"(crc)
-                        : "0"(crc), "c"(*p)
-                );
-                p++;
-        }
-
-        return crc;
-}
-
-#if BITS_PER_LONG > 32
-#define WORD_SHIFT 3
-#define WORD_MASK  7
-#define REX "0x48, "
-#else
-#define WORD_SHIFT 2
-#define WORD_MASK  3
-#define REX ""
-#endif
-
-/* Do we need to worry about unaligned input data here? */
-static inline __u32 crc32c_hw(__u32 crc, unsigned char const *p, size_t len)
-{
-        unsigned int words = len >> WORD_SHIFT;
-        unsigned int bytes = len &  WORD_MASK;
-        long *ptmp = (long *)p;
-
-        while (words--) {
-                __asm__ __volatile__(
-                        ".byte 0xf2, " REX "0xf, 0x38, 0xf1, 0xf1;"
-                        : "=S"(crc)
-                        : "0"(crc), "c"(*ptmp)
-                );
-                ptmp++;
-        }
-
-        if (bytes)
-                crc = crc32c_hw_byte(crc, (unsigned char *)ptmp, bytes);
-
-        return crc;
-}
-#else
-/* We should never call this unless the CPU has previously been detected to
- * support this instruction in the SSE4.2 feature set. b=23549  */
-static inline __u32 crc32c_hw(__u32 crc, unsigned char const *p,size_t len)
-{
-        LBUG();
-}
-#endif
-
-static inline __u32 init_checksum(cksum_type_t cksum_type)
-{
-        switch(cksum_type) {
-        case OBD_CKSUM_CRC32C:
-                return ~0U;
-#ifdef HAVE_ADLER
-        case OBD_CKSUM_ADLER:
-                return 1U;
-#endif
-        case OBD_CKSUM_CRC32:
-                return ~0U;
-        default:
-                CERROR("Unknown checksum type (%x)!!!\n", cksum_type);
-                LBUG();
-        }
-        return 0;
-}
-
-static inline __u32 fini_checksum(__u32 cksum, cksum_type_t cksum_type)
-{
-        if (cksum_type == OBD_CKSUM_CRC32C)
-                return ~cksum;
-        return cksum;
-}
-
-static inline __u32 compute_checksum(__u32 cksum, unsigned char const *p,
-                                     size_t len, cksum_type_t cksum_type)
-{
-        switch(cksum_type) {
-        case OBD_CKSUM_CRC32C:
-                return crc32c_hw(cksum, p, len);
-#ifdef HAVE_ADLER
-        case OBD_CKSUM_ADLER:
-                return adler32(cksum, p, len);
-#endif
-        case OBD_CKSUM_CRC32:
-                return crc32_le(cksum, p, len);
-        default:
-                CERROR("Unknown checksum type (%x)!!!\n", cksum_type);
-                LBUG();
-        }
-        return 0;
+       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
@@ -194,79 +60,113 @@ static inline __u32 compute_checksum(__u32 cksum, unsigned char const *p,
  * 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 CRC32 (even though
- * it isn't very fast) because that is supported by all clients
- * checksums, since 1.6.5 (or earlier via patches).
+ * In case of an unsupported types/flags we fall back to ADLER
+ * because that is supported by all clients since 1.8
  *
- * These flags should be listed in order of descending performance, so that
- * in case multiple algorithms are supported the best one is used. */
+ * In case multiple algorithms are supported the best one is used. */
 static inline obd_flag cksum_type_pack(cksum_type_t cksum_type)
 {
-        if (cksum_type & OBD_CKSUM_CRC32C)
-                return OBD_FL_CKSUM_CRC32C;
-#ifdef HAVE_ADLER
-        if (cksum_type & OBD_CKSUM_ADLER)
-                return OBD_FL_CKSUM_ADLER;
-#endif
-        if (unlikely(cksum_type && !(cksum_type & OBD_CKSUM_CRC32)))
-                CWARN("unknown cksum type %x\n", cksum_type);
-
-        return OBD_FL_CKSUM_CRC32;
+       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_ADLER:
-#ifdef HAVE_ADLER
-                return OBD_CKSUM_ADLER;
-#else
-                CWARN("checksum type is set to adler32, but adler32 is not "
-                      "supported (%x)\n", o_flags);
-                break;
-#endif
-        default:
-                break;
-        }
-
-        /* 1.6.4- only supported CRC32 and didn't set o_flags */
-        return OBD_CKSUM_CRC32;
+       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.
- *
- * CRC32 is a required for compatibility (starting with 1.6.5),
- * after which we could move to Adler as the base checksum type.
- *
- * If hardware crc32c support is not available, it is slower than Adler,
- * so don't include it, even if it could be emulated in software. b=23549 */
-static inline cksum_type_t cksum_types_supported(void)
+ * 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_CRC32;
+       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;
 
-#ifdef X86_FEATURE_XMM4_2
-        if (cpu_has_xmm4_2)
-                ret |= OBD_CKSUM_CRC32C;
-#endif
-#ifdef HAVE_ADLER
-        ret |= OBD_CKSUM_ADLER;
-#endif
-        return ret;
+       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 ordering, but in the future we might want to
- * determine this based on benchmarking the different algorithms quickly.
+ * 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));
+       return cksum_type_unpack(cksum_type_pack(cksum_types));
 }
 
 /* Checksum algorithm names. Must be defined in the same order as the