fs/ceph/rados.h

#ifndef __RADOS_H
#define __RADOS_H

/*
 * Data types for the Ceph distributed object storage layer RADOS
 * (Reliable Autonomic Distributed Object Store).
 */

#include "msgr.h"

/*
 * fs id
 */
struct ceph_fsid {
	unsigned char fsid[16];
};

static inline int ceph_fsid_compare(const struct ceph_fsid *a,
				    const struct ceph_fsid *b)
{
	return memcmp(a, b, sizeof(*a));
}

/*
 * ino, object, etc.
 */
typedef __le64 ceph_snapid_t;
#define CEPH_SNAPDIR ((__u64)(-1))  /* reserved for hidden .snap dir */
#define CEPH_NOSNAP  ((__u64)(-2))  /* "head", "live" revision */
#define CEPH_MAXSNAP ((__u64)(-3))  /* largest valid snapid */

struct ceph_timespec {
	__le32 tv_sec;
	__le32 tv_nsec;
} __attribute__ ((packed));


/*
 * object layout - how objects are mapped into PGs
 */
#define CEPH_OBJECT_LAYOUT_HASH     1
#define CEPH_OBJECT_LAYOUT_LINEAR   2
#define CEPH_OBJECT_LAYOUT_HASHINO  3

/*
 * pg layout -- how PGs are mapped onto (sets of) OSDs
 */
#define CEPH_PG_LAYOUT_CRUSH  0
#define CEPH_PG_LAYOUT_HASH   1
#define CEPH_PG_LAYOUT_LINEAR 2
#define CEPH_PG_LAYOUT_HYBRID 3


/*
 * placement group.
 * we encode this into one __le64.
 */
union ceph_pg {
	__u64 pg64;
	struct {
		__s16 preferred; /* preferred primary osd */
		__u16 ps;        /* placement seed */
		__u32 pool;      /* object pool */
	} __attribute__ ((packed)) pg;
} __attribute__ ((packed));

/*
 * pg_pool is a set of pgs storing a pool of objects
 *
 *  pg_num -- base number of pseudorandomly placed pgs
 *
 *  pgp_num -- effective number when calculating pg placement.  this
 * is used for pg_num increases.  new pgs result in data being "split"
 * into new pgs.  for this to proceed smoothly, new pgs are intiially
 * colocated with their parents; that is, pgp_num doesn't increase
 * until the new pgs have successfully split.  only _then_ are the new
 * pgs placed independently.
 *
 *  lpg_num -- localized pg count (per device).  replicas are randomly
 * selected.
 *
 *  lpgp_num -- as above.
 */
#define CEPH_PG_TYPE_REP     1
#define CEPH_PG_TYPE_RAID4   2
struct ceph_pg_pool {
	__u8 type;                /* CEPH_PG_TYPE_* */
	__u8 size;                /* number of osds in each pg */
	__u8 crush_ruleset;       /* crush placement rule */
	__le32 pg_num, pgp_num;   /* number of pg's */
	__le32 lpg_num, lpgp_num; /* number of localized pg's */
	__le32 last_change;       /* most recent epoch changed */
	__le64 snap_seq;          /* seq for per-pool snapshot */
	__le32 snap_epoch;        /* epoch of last snap */
	__le32 num_snaps;
	__le32 num_removed_snap_intervals;
} __attribute__ ((packed));

/*
 * stable_mod func is used to control number of placement groups.
 * similar to straight-up modulo, but produces a stable mapping as b
 * increases over time.  b is the number of bins, and bmask is the
 * containing power of 2 minus 1.
 *
 * b <= bmask and bmask=(2**n)-1
 * e.g., b=12 -> bmask=15, b=123 -> bmask=127
 */
static inline int ceph_stable_mod(int x, int b, int bmask)
{
	if ((x & bmask) < b)
		return x & bmask;
	else
		return x & (bmask >> 1);
}

/*
 * object layout - how a given object should be stored.
 */
struct ceph_object_layout {
	__le64 ol_pgid;           /* raw pg, with _full_ ps precision. */
	__le32 ol_stripe_unit;    /* for per-object parity, if any */
} __attribute__ ((packed));

/*
 * compound epoch+version, used by storage layer to serialize mutations
 */
struct ceph_eversion {
	__le32 epoch;
	__le64 version;
} __attribute__ ((packed));

/*
 * osd map bits
 */

/* status bits */
#define CEPH_OSD_EXISTS 1
#define CEPH_OSD_UP     2

/* osd weights.  fixed point value: 0x10000 == 1.0 ("in"), 0 == "out" */
#define CEPH_OSD_IN  0x10000
#define CEPH_OSD_OUT 0


/*
 * osd map flag bits
 */
#define CEPH_OSDMAP_NEARFULL (1<<0)  /* sync writes (near ENOSPC) */
#define CEPH_OSDMAP_FULL     (1<<1)  /* no data writes (ENOSPC) */
#define CEPH_OSDMAP_PAUSERD  (1<<2)  /* pause all reads */
#define CEPH_OSDMAP_PAUSEWR  (1<<3)  /* pause all writes */
#define CEPH_OSDMAP_PAUSEREC (1<<4)  /* pause recovery */

/*
 * osd ops
 */
#define CEPH_OSD_OP_MODE       0xf000
#define CEPH_OSD_OP_MODE_RD    0x1000
#define CEPH_OSD_OP_MODE_WR    0x2000
#define CEPH_OSD_OP_MODE_RMW   0x3000
#define CEPH_OSD_OP_MODE_SUB   0x4000
#define CEPH_OSD_OP_MODE_EXEC  0x8000

#define CEPH_OSD_OP_TYPE       0x0f00
#define CEPH_OSD_OP_TYPE_LOCK  0x0100
#define CEPH_OSD_OP_TYPE_DATA  0x0200
#define CEPH_OSD_OP_TYPE_ATTR  0x0300
#define CEPH_OSD_OP_TYPE_EXEC  0x0400
#define CEPH_OSD_OP_TYPE_PG    0x0500

enum {
	/** data **/
	/* read */
	CEPH_OSD_OP_READ      = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_DATA | 1,
	CEPH_OSD_OP_STAT      = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_DATA | 2,

	/* fancy read */
	CEPH_OSD_OP_MASKTRUNC = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_DATA | 4,

	/* write */
	CEPH_OSD_OP_WRITE     = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 1,
	CEPH_OSD_OP_WRITEFULL = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 2,
	CEPH_OSD_OP_TRUNCATE  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 3,
	CEPH_OSD_OP_ZERO      = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 4,
	CEPH_OSD_OP_DELETE    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 5,

	/* fancy write */
	CEPH_OSD_OP_APPEND    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 6,
	CEPH_OSD_OP_STARTSYNC = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 7,
	CEPH_OSD_OP_SETTRUNC  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 8,
	CEPH_OSD_OP_TRIMTRUNC = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 9,

	CEPH_OSD_OP_TMAPUP  = CEPH_OSD_OP_MODE_RMW | CEPH_OSD_OP_TYPE_DATA | 10,
	CEPH_OSD_OP_TMAPPUT = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 11,
	CEPH_OSD_OP_TMAPGET = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_DATA | 12,

	CEPH_OSD_OP_CREATE  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 13,

	/** attrs **/
	/* read */
	CEPH_OSD_OP_GETXATTR  = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_ATTR | 1,
	CEPH_OSD_OP_GETXATTRS = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_ATTR | 2,

	/* write */
	CEPH_OSD_OP_SETXATTR  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_ATTR | 1,
	CEPH_OSD_OP_SETXATTRS = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_ATTR | 2,
	CEPH_OSD_OP_RESETXATTRS = CEPH_OSD_OP_MODE_WR|CEPH_OSD_OP_TYPE_ATTR | 3,
	CEPH_OSD_OP_RMXATTR   = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_ATTR | 4,

	/** subop **/
	CEPH_OSD_OP_PULL           = CEPH_OSD_OP_MODE_SUB | 1,
	CEPH_OSD_OP_PUSH           = CEPH_OSD_OP_MODE_SUB | 2,
	CEPH_OSD_OP_BALANCEREADS   = CEPH_OSD_OP_MODE_SUB | 3,
	CEPH_OSD_OP_UNBALANCEREADS = CEPH_OSD_OP_MODE_SUB | 4,
	CEPH_OSD_OP_SCRUB          = CEPH_OSD_OP_MODE_SUB | 5,

	/** lock **/
	CEPH_OSD_OP_WRLOCK    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 1,
	CEPH_OSD_OP_WRUNLOCK  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 2,
	CEPH_OSD_OP_RDLOCK    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 3,
	CEPH_OSD_OP_RDUNLOCK  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 4,
	CEPH_OSD_OP_UPLOCK    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 5,
	CEPH_OSD_OP_DNLOCK    = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_LOCK | 6,

	/** exec **/
	CEPH_OSD_OP_CALL    = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_EXEC | 1,

	/** pg **/
	CEPH_OSD_OP_PGLS      = CEPH_OSD_OP_MODE_RD | CEPH_OSD_OP_TYPE_PG | 1,
};

static inline int ceph_osd_op_type_lock(int op)
{
	return (op & CEPH_OSD_OP_TYPE) == CEPH_OSD_OP_TYPE_LOCK;
}
static inline int ceph_osd_op_type_data(int op)
{
	return (op & CEPH_OSD_OP_TYPE) == CEPH_OSD_OP_TYPE_DATA;
}
static inline int ceph_osd_op_type_attr(int op)
{
	return (op & CEPH_OSD_OP_TYPE) == CEPH_OSD_OP_TYPE_ATTR;
}
static inline int ceph_osd_op_type_exec(int op)
{
	return (op & CEPH_OSD_OP_TYPE) == CEPH_OSD_OP_TYPE_EXEC;
}
static inline int ceph_osd_op_type_pg(int op)
{
	return (op & CEPH_OSD_OP_TYPE) == CEPH_OSD_OP_TYPE_PG;
}

static inline int ceph_osd_op_mode_subop(int op)
{
	return (op & CEPH_OSD_OP_MODE) == CEPH_OSD_OP_MODE_SUB;
}
static inline int ceph_osd_op_mode_read(int op)
{
	return (op & CEPH_OSD_OP_MODE) == CEPH_OSD_OP_MODE_RD;
}
static inline int ceph_osd_op_mode_modify(int op)
{
	return (op & CEPH_OSD_OP_MODE) == CEPH_OSD_OP_MODE_WR;
}

#define CEPH_OSD_TMAP_HDR 'h'
#define CEPH_OSD_TMAP_SET 's'
#define CEPH_OSD_TMAP_RM  'r'

extern const char *ceph_osd_op_name(int op);


/*
 * osd op flags
 *
 * An op may be READ, WRITE, or READ|WRITE.
 */
enum {
	CEPH_OSD_FLAG_ACK = 1,          /* want (or is) "ack" ack */
	CEPH_OSD_FLAG_ONNVRAM = 2,      /* want (or is) "onnvram" ack */
	CEPH_OSD_FLAG_ONDISK = 4,       /* want (or is) "ondisk" ack */
	CEPH_OSD_FLAG_RETRY = 8,        /* resend attempt */
	CEPH_OSD_FLAG_READ = 16,        /* op may read */
	CEPH_OSD_FLAG_WRITE = 32,       /* op may write */
	CEPH_OSD_FLAG_ORDERSNAP = 64,   /* EOLDSNAP if snapc is out of order */
	CEPH_OSD_FLAG_PEERSTAT = 128,   /* msg includes osd_peer_stat */
	CEPH_OSD_FLAG_BALANCE_READS = 256,
	CEPH_OSD_FLAG_PARALLELEXEC = 512, /* execute op in parallel */
	CEPH_OSD_FLAG_PGOP = 1024,      /* pg op, no object */
};

enum {
	CEPH_OSD_OP_FLAG_EXCL = 1,      /* EXCL object create */
};

#define EOLDSNAPC    ERESTART  /* ORDERSNAP flag set; writer has old snapc*/
#define EBLACKLISTED ESHUTDOWN /* blacklisted */

/*
 * an individual object operation.  each may be accompanied by some data
 * payload
 */
struct ceph_osd_op {
	__le16 op;           /* CEPH_OSD_OP_* */
	__le32 flags;        /* CEPH_OSD_FLAG_* */
	union {
		struct {
			__le64 offset, length;
		} __attribute__ ((packed)) extent;
		struct {
			__le32 name_len;
			__le32 value_len;
		} __attribute__ ((packed)) xattr;
		struct {
			__le64 truncate_size;
			__le32 truncate_seq;
		} __attribute__ ((packed)) trunc;
		struct {
			__u8 class_len;
			__u8 method_len;
			__u8 argc;
			__le32 indata_len;
		} __attribute__ ((packed)) cls;
		struct {
			__le64 cookie, count;
		} __attribute__ ((packed)) pgls;
	};
	__le32 payload_len;
} __attribute__ ((packed));

/*
 * osd request message header.  each request may include multiple
 * ceph_osd_op object operations.
 */
struct ceph_osd_request_head {
	__le64 tid;                        /* transaction id */
	__le32 client_inc;                 /* client incarnation */
	struct ceph_object_layout layout;  /* pgid */
	__le32 osdmap_epoch;               /* client's osdmap epoch */

	__le32 flags;

	struct ceph_timespec mtime;        /* for mutations only */
	struct ceph_eversion reassert_version; /* if we are replaying op */

	__le32 object_len;     /* length of object name */

	__le64 snapid;         /* snapid to read */
	__le64 snap_seq;       /* writer's snap context */
	__le32 num_snaps;

	__le16 num_ops;
	struct ceph_osd_op ops[];  /* followed by ops[], obj, ticket, snaps */
} __attribute__ ((packed));

struct ceph_osd_reply_head {
	__le64 tid;                       /* transaction id */
	__le32 client_inc;                /* client incarnation */
	__le32 flags;
	struct ceph_object_layout layout;
	__le32 osdmap_epoch;
	struct ceph_eversion reassert_version; /* for replaying uncommitted */

	__le32 result;                    /* result code */

	__le32 object_len;                /* length of object name */
	__le32 num_ops;
	struct ceph_osd_op ops[0];  /* ops[], object */
} __attribute__ ((packed));


#endif