Commit 1654dd0c authored by Sage Weil's avatar Sage Weil
Browse files

ceph: make object hash a pg_pool property 



The object will be hashed to a placement seed (ps) based on the pg_pool's
hash function.  This allows new hashes to be introduced into an existing
object store, or selection of a hash appropriate to the objects that
will be stored in a particular pool.

Signed-off-by: default avatarSage Weil <sage@newdream.net>
parent cfbbcd24

fs/ceph/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -13,7 +13,7 @@ ceph-objs := super.o inode.o dir.o file.o addr.o ioctl.o \ 
	mon_client.o \

	osd_client.o osdmap.o crush/crush.o crush/mapper.o crush/hash.o \

	debugfs.o \

	ceph_fs.o ceph_strings.o ceph_frag.o

	ceph_fs.o ceph_strings.o ceph_hash.o ceph_frag.o



else

#Otherwise we were called directly from the command

fs/ceph/README

+2 −0
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ src/include/rados.h fs/ceph/rados.h 
src/include/ceph_strings.cc fs/ceph/ceph_strings.c

src/include/ceph_frag.h	    fs/ceph/ceph_frag.h

src/include/ceph_frag.cc    fs/ceph/ceph_frag.c

src/include/ceph_hash.h	    fs/ceph/ceph_hash.h

src/include/ceph_hash.cc    fs/ceph/ceph_hash.c

src/crush/crush.c	    fs/ceph/crush/crush.c

src/crush/crush.h	    fs/ceph/crush/crush.h

src/crush/mapper.c	    fs/ceph/crush/mapper.c

fs/ceph/ceph_fs.c

+0 −77
Original line number Diff line number Diff line
@@ -72,80 +72,3 @@ int ceph_caps_for_mode(int mode) 
	}

	return 0;

}
 


/*

 * Robert Jenkin's hash function.

 * http://burtleburtle.net/bob/hash/evahash.html

 * This is in the public domain.

 */

#define mix(a, b, c)						\

	do {							\

		a = a - b;  a = a - c;  a = a ^ (c >> 13);	\

		b = b - c;  b = b - a;  b = b ^ (a << 8);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 13);	\

		a = a - b;  a = a - c;  a = a ^ (c >> 12);	\

		b = b - c;  b = b - a;  b = b ^ (a << 16);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 5);	\

		a = a - b;  a = a - c;  a = a ^ (c >> 3);	\

		b = b - c;  b = b - a;  b = b ^ (a << 10);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 15);	\

	} while (0)



unsigned int ceph_full_name_hash(const char *str, unsigned int length)

{

	const unsigned char *k = (const unsigned char *)str;

	__u32 a, b, c;  /* the internal state */

	__u32 len;      /* how many key bytes still need mixing */



	/* Set up the internal state */

	len = length;

	a = 0x9e3779b9;      /* the golden ratio; an arbitrary value */

	b = a;

	c = 0;               /* variable initialization of internal state */



	/* handle most of the key */

	while (len >= 12) {

		a = a + (k[0] + ((__u32)k[1] << 8) + ((__u32)k[2] << 16) +

			 ((__u32)k[3] << 24));

		b = b + (k[4] + ((__u32)k[5] << 8) + ((__u32)k[6] << 16) +

			 ((__u32)k[7] << 24));

		c = c + (k[8] + ((__u32)k[9] << 8) + ((__u32)k[10] << 16) +

			 ((__u32)k[11] << 24));

		mix(a, b, c);

		k = k + 12;

		len = len - 12;

	}



	/* handle the last 11 bytes */

	c = c + length;

	switch (len) {            /* all the case statements fall through */

	case 11:

		c = c + ((__u32)k[10] << 24);

	case 10:

		c = c + ((__u32)k[9] << 16);

	case 9:

		c = c + ((__u32)k[8] << 8);

		/* the first byte of c is reserved for the length */

	case 8:

		b = b + ((__u32)k[7] << 24);

	case 7:

		b = b + ((__u32)k[6] << 16);

	case 6:

		b = b + ((__u32)k[5] << 8);

	case 5:

		b = b + k[4];

	case 4:

		a = a + ((__u32)k[3] << 24);

	case 3:

		a = a + ((__u32)k[2] << 16);

	case 2:

		a = a + ((__u32)k[1] << 8);

	case 1:

		a = a + k[0];

		/* case 0: nothing left to add */

	}

	mix(a, b, c);



	return c;

}

fs/ceph/ceph_fs.h

+0 −2
Original line number Diff line number Diff line
@@ -49,8 +49,6 @@ 
#define CEPH_MAX_MON   31





unsigned int ceph_full_name_hash(const char *name, unsigned int len);





/*

 * ceph_file_layout - describe data layout for a file/inode

fs/ceph/ceph_hash.c

0 → 100644
+118 −0
Original line number Diff line number Diff line 


#include "types.h"



/*

 * Robert Jenkin's hash function.

 * http://burtleburtle.net/bob/hash/evahash.html

 * This is in the public domain.

 */

#define mix(a, b, c)						\

	do {							\

		a = a - b;  a = a - c;  a = a ^ (c >> 13);	\

		b = b - c;  b = b - a;  b = b ^ (a << 8);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 13);	\

		a = a - b;  a = a - c;  a = a ^ (c >> 12);	\

		b = b - c;  b = b - a;  b = b ^ (a << 16);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 5);	\

		a = a - b;  a = a - c;  a = a ^ (c >> 3);	\

		b = b - c;  b = b - a;  b = b ^ (a << 10);	\

		c = c - a;  c = c - b;  c = c ^ (b >> 15);	\

	} while (0)



unsigned ceph_str_hash_rjenkins(const char *str, unsigned length)

{

	const unsigned char *k = (const unsigned char *)str;

	__u32 a, b, c;  /* the internal state */

	__u32 len;      /* how many key bytes still need mixing */



	/* Set up the internal state */

	len = length;

	a = 0x9e3779b9;      /* the golden ratio; an arbitrary value */

	b = a;

	c = 0;               /* variable initialization of internal state */



	/* handle most of the key */

	while (len >= 12) {

		a = a + (k[0] + ((__u32)k[1] << 8) + ((__u32)k[2] << 16) +

			 ((__u32)k[3] << 24));

		b = b + (k[4] + ((__u32)k[5] << 8) + ((__u32)k[6] << 16) +

			 ((__u32)k[7] << 24));

		c = c + (k[8] + ((__u32)k[9] << 8) + ((__u32)k[10] << 16) +

			 ((__u32)k[11] << 24));

		mix(a, b, c);

		k = k + 12;

		len = len - 12;

	}



	/* handle the last 11 bytes */

	c = c + length;

	switch (len) {            /* all the case statements fall through */

	case 11:

		c = c + ((__u32)k[10] << 24);

	case 10:

		c = c + ((__u32)k[9] << 16);

	case 9:

		c = c + ((__u32)k[8] << 8);

		/* the first byte of c is reserved for the length */

	case 8:

		b = b + ((__u32)k[7] << 24);

	case 7:

		b = b + ((__u32)k[6] << 16);

	case 6:

		b = b + ((__u32)k[5] << 8);

	case 5:

		b = b + k[4];

	case 4:

		a = a + ((__u32)k[3] << 24);

	case 3:

		a = a + ((__u32)k[2] << 16);

	case 2:

		a = a + ((__u32)k[1] << 8);

	case 1:

		a = a + k[0];

		/* case 0: nothing left to add */

	}

	mix(a, b, c);



	return c;

}



/*

 * linux dcache hash

 */

unsigned ceph_str_hash_linux(const char *str, unsigned length)

{

        unsigned long hash = 0;

	unsigned char c;



        while (length-- > 0) {

		c = *str++;

		hash = (hash + (c << 4) + (c >> 4)) * 11;

	}

        return hash;

}





unsigned ceph_str_hash(int type, const char *s, unsigned len)

{

	switch (type) {

	case CEPH_STR_HASH_LINUX:

		return ceph_str_hash_linux(s, len);

	case CEPH_STR_HASH_RJENKINS:

		return ceph_str_hash_rjenkins(s, len);

	default:

		return -1;

	}

}



const char *ceph_str_hash_name(int type) 

{

	switch (type) {

	case CEPH_STR_HASH_LINUX:

		return "linux";

	case CEPH_STR_HASH_RJENKINS:

		return "rjenkins";

	default:

		return "unknown";

	}

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE