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linux/drivers/block/drbd/drbd_int.h
Lars Ellenberg e7f52dfb4f drbd: revert "delay probes", feature is being re-implemented differently 
It was a now abandoned attempt to throttle resync bandwidth
based on the delay it causes on the bulk data socket.
It has no userbase yet, and has been disabled by
9173465ccb51c09cc3102a10af93e9f469a0af6f already.
This removes the now unused code.

The basic feature, namely using up "idle" bandwith
of network and disk IO subsystem, with minimal impact
to application IO, is being reimplemented differently.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:53:57 +02:00

2333 lines
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/*
drbd_int.h
This file is part of DRBD by Philipp Reisner and Lars Ellenberg.
Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.
drbd is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
drbd 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 for more details.
You should have received a copy of the GNU General Public License
along with drbd; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _DRBD_INT_H
#define _DRBD_INT_H
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/version.h>
#include <linux/list.h>
#include <linux/sched.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/crypto.h>
#include <linux/ratelimit.h>
#include <linux/tcp.h>
#include <linux/mutex.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/genhd.h>
#include <net/tcp.h>
#include <linux/lru_cache.h>
#ifdef __CHECKER__
# define __protected_by(x) __attribute__((require_context(x,1,999,"rdwr")))
# define __protected_read_by(x) __attribute__((require_context(x,1,999,"read")))
# define __protected_write_by(x) __attribute__((require_context(x,1,999,"write")))
# define __must_hold(x) __attribute__((context(x,1,1), require_context(x,1,999,"call")))
#else
# define __protected_by(x)
# define __protected_read_by(x)
# define __protected_write_by(x)
# define __must_hold(x)
#endif
#define __no_warn(lock, stmt) do { __acquire(lock); stmt; __release(lock); } while (0)
/* module parameter, defined in drbd_main.c */
extern unsigned int minor_count;
extern int disable_sendpage;
extern int allow_oos;
extern unsigned int cn_idx;
#ifdef CONFIG_DRBD_FAULT_INJECTION
extern int enable_faults;
extern int fault_rate;
extern int fault_devs;
#endif
extern char usermode_helper[];
#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif
/* I don't remember why XCPU ...
* This is used to wake the asender,
* and to interrupt sending the sending task
* on disconnect.
*/
#define DRBD_SIG SIGXCPU
/* This is used to stop/restart our threads.
* Cannot use SIGTERM nor SIGKILL, since these
* are sent out by init on runlevel changes
* I choose SIGHUP for now.
*/
#define DRBD_SIGKILL SIGHUP
/* All EEs on the free list should have ID_VACANT (== 0)
* freshly allocated EEs get !ID_VACANT (== 1)
* so if it says "cannot dereference null pointer at address 0x00000001",
* it is most likely one of these :( */
#define ID_IN_SYNC (4711ULL)
#define ID_OUT_OF_SYNC (4712ULL)
#define ID_SYNCER (-1ULL)
#define ID_VACANT 0
#define is_syncer_block_id(id) ((id) == ID_SYNCER)
struct drbd_conf;
/* to shorten dev_warn(DEV, "msg"); and relatives statements */
#define DEV (disk_to_dev(mdev->vdisk))
#define D_ASSERT(exp) if (!(exp)) \
dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__)
#define ERR_IF(exp) if (({ \
int _b = (exp) != 0; \
if (_b) dev_err(DEV, "%s: (%s) in %s:%d\n", \
__func__, #exp, __FILE__, __LINE__); \
_b; \
}))
/* Defines to control fault insertion */
enum {
DRBD_FAULT_MD_WR = 0, /* meta data write */
DRBD_FAULT_MD_RD = 1, /* read */
DRBD_FAULT_RS_WR = 2, /* resync */
DRBD_FAULT_RS_RD = 3,
DRBD_FAULT_DT_WR = 4, /* data */
DRBD_FAULT_DT_RD = 5,
DRBD_FAULT_DT_RA = 6, /* data read ahead */
DRBD_FAULT_BM_ALLOC = 7, /* bitmap allocation */
DRBD_FAULT_AL_EE = 8, /* alloc ee */
DRBD_FAULT_RECEIVE = 9, /* Changes some bytes upon receiving a [rs]data block */
DRBD_FAULT_MAX,
};
#ifdef CONFIG_DRBD_FAULT_INJECTION
extern unsigned int
_drbd_insert_fault(struct drbd_conf *mdev, unsigned int type);
static inline int
drbd_insert_fault(struct drbd_conf *mdev, unsigned int type) {
return fault_rate &&
(enable_faults & (1<<type)) &&
_drbd_insert_fault(mdev, type);
}
#define FAULT_ACTIVE(_m, _t) (drbd_insert_fault((_m), (_t)))
#else
#define FAULT_ACTIVE(_m, _t) (0)
#endif
/* integer division, round _UP_ to the next integer */
#define div_ceil(A, B) ((A)/(B) + ((A)%(B) ? 1 : 0))
/* usual integer division */
#define div_floor(A, B) ((A)/(B))
/* drbd_meta-data.c (still in drbd_main.c) */
/* 4th incarnation of the disk layout. */
#define DRBD_MD_MAGIC (DRBD_MAGIC+4)
extern struct drbd_conf **minor_table;
extern struct ratelimit_state drbd_ratelimit_state;
/* on the wire */
enum drbd_packets {
/* receiver (data socket) */
P_DATA = 0x00,
P_DATA_REPLY = 0x01, /* Response to P_DATA_REQUEST */
P_RS_DATA_REPLY = 0x02, /* Response to P_RS_DATA_REQUEST */
P_BARRIER = 0x03,
P_BITMAP = 0x04,
P_BECOME_SYNC_TARGET = 0x05,
P_BECOME_SYNC_SOURCE = 0x06,
P_UNPLUG_REMOTE = 0x07, /* Used at various times to hint the peer */
P_DATA_REQUEST = 0x08, /* Used to ask for a data block */
P_RS_DATA_REQUEST = 0x09, /* Used to ask for a data block for resync */
P_SYNC_PARAM = 0x0a,
P_PROTOCOL = 0x0b,
P_UUIDS = 0x0c,
P_SIZES = 0x0d,
P_STATE = 0x0e,
P_SYNC_UUID = 0x0f,
P_AUTH_CHALLENGE = 0x10,
P_AUTH_RESPONSE = 0x11,
P_STATE_CHG_REQ = 0x12,
/* asender (meta socket */
P_PING = 0x13,
P_PING_ACK = 0x14,
P_RECV_ACK = 0x15, /* Used in protocol B */
P_WRITE_ACK = 0x16, /* Used in protocol C */
P_RS_WRITE_ACK = 0x17, /* Is a P_WRITE_ACK, additionally call set_in_sync(). */
P_DISCARD_ACK = 0x18, /* Used in proto C, two-primaries conflict detection */
P_NEG_ACK = 0x19, /* Sent if local disk is unusable */
P_NEG_DREPLY = 0x1a, /* Local disk is broken... */
P_NEG_RS_DREPLY = 0x1b, /* Local disk is broken... */
P_BARRIER_ACK = 0x1c,
P_STATE_CHG_REPLY = 0x1d,
/* "new" commands, no longer fitting into the ordering scheme above */
P_OV_REQUEST = 0x1e, /* data socket */
P_OV_REPLY = 0x1f,
P_OV_RESULT = 0x20, /* meta socket */
P_CSUM_RS_REQUEST = 0x21, /* data socket */
P_RS_IS_IN_SYNC = 0x22, /* meta socket */
P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */
P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */
/* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */
/* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */
P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */
P_MAX_CMD = 0x28,
P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
P_MAX_OPT_CMD = 0x101,
/* special command ids for handshake */
P_HAND_SHAKE_M = 0xfff1, /* First Packet on the MetaSock */
P_HAND_SHAKE_S = 0xfff2, /* First Packet on the Socket */
P_HAND_SHAKE = 0xfffe /* FIXED for the next century! */
};
static inline const char *cmdname(enum drbd_packets cmd)
{
/* THINK may need to become several global tables
* when we want to support more than
* one PRO_VERSION */
static const char *cmdnames[] = {
[P_DATA] = "Data",
[P_DATA_REPLY] = "DataReply",
[P_RS_DATA_REPLY] = "RSDataReply",
[P_BARRIER] = "Barrier",
[P_BITMAP] = "ReportBitMap",
[P_BECOME_SYNC_TARGET] = "BecomeSyncTarget",
[P_BECOME_SYNC_SOURCE] = "BecomeSyncSource",
[P_UNPLUG_REMOTE] = "UnplugRemote",
[P_DATA_REQUEST] = "DataRequest",
[P_RS_DATA_REQUEST] = "RSDataRequest",
[P_SYNC_PARAM] = "SyncParam",
[P_SYNC_PARAM89] = "SyncParam89",
[P_PROTOCOL] = "ReportProtocol",
[P_UUIDS] = "ReportUUIDs",
[P_SIZES] = "ReportSizes",
[P_STATE] = "ReportState",
[P_SYNC_UUID] = "ReportSyncUUID",
[P_AUTH_CHALLENGE] = "AuthChallenge",
[P_AUTH_RESPONSE] = "AuthResponse",
[P_PING] = "Ping",
[P_PING_ACK] = "PingAck",
[P_RECV_ACK] = "RecvAck",
[P_WRITE_ACK] = "WriteAck",
[P_RS_WRITE_ACK] = "RSWriteAck",
[P_DISCARD_ACK] = "DiscardAck",
[P_NEG_ACK] = "NegAck",
[P_NEG_DREPLY] = "NegDReply",
[P_NEG_RS_DREPLY] = "NegRSDReply",
[P_BARRIER_ACK] = "BarrierAck",
[P_STATE_CHG_REQ] = "StateChgRequest",
[P_STATE_CHG_REPLY] = "StateChgReply",
[P_OV_REQUEST] = "OVRequest",
[P_OV_REPLY] = "OVReply",
[P_OV_RESULT] = "OVResult",
[P_CSUM_RS_REQUEST] = "CsumRSRequest",
[P_RS_IS_IN_SYNC] = "CsumRSIsInSync",
[P_COMPRESSED_BITMAP] = "CBitmap",
[P_DELAY_PROBE] = "DelayProbe",
[P_MAX_CMD] = NULL,
};
if (cmd == P_HAND_SHAKE_M)
return "HandShakeM";
if (cmd == P_HAND_SHAKE_S)
return "HandShakeS";
if (cmd == P_HAND_SHAKE)
return "HandShake";
if (cmd >= P_MAX_CMD)
return "Unknown";
return cmdnames[cmd];
}
/* for sending/receiving the bitmap,
* possibly in some encoding scheme */
struct bm_xfer_ctx {
/* "const"
* stores total bits and long words
* of the bitmap, so we don't need to
* call the accessor functions over and again. */
unsigned long bm_bits;
unsigned long bm_words;
/* during xfer, current position within the bitmap */
unsigned long bit_offset;
unsigned long word_offset;
/* statistics; index: (h->command == P_BITMAP) */
unsigned packets[2];
unsigned bytes[2];
};
extern void INFO_bm_xfer_stats(struct drbd_conf *mdev,
const char *direction, struct bm_xfer_ctx *c);
static inline void bm_xfer_ctx_bit_to_word_offset(struct bm_xfer_ctx *c)
{
/* word_offset counts "native long words" (32 or 64 bit),
* aligned at 64 bit.
* Encoded packet may end at an unaligned bit offset.
* In case a fallback clear text packet is transmitted in
* between, we adjust this offset back to the last 64bit
* aligned "native long word", which makes coding and decoding
* the plain text bitmap much more convenient. */
#if BITS_PER_LONG == 64
c->word_offset = c->bit_offset >> 6;
#elif BITS_PER_LONG == 32
c->word_offset = c->bit_offset >> 5;
c->word_offset &= ~(1UL);
#else
# error "unsupported BITS_PER_LONG"
#endif
}
#ifndef __packed
#define __packed __attribute__((packed))
#endif
/* This is the layout for a packet on the wire.
* The byteorder is the network byte order.
* (except block_id and barrier fields.
* these are pointers to local structs
* and have no relevance for the partner,
* which just echoes them as received.)
*
* NOTE that the payload starts at a long aligned offset,
* regardless of 32 or 64 bit arch!
*/
struct p_header {
u32 magic;
u16 command;
u16 length; /* bytes of data after this header */
u8 payload[0];
} __packed;
/* 8 bytes. packet FIXED for the next century! */
/*
* short commands, packets without payload, plain p_header:
* P_PING
* P_PING_ACK
* P_BECOME_SYNC_TARGET
* P_BECOME_SYNC_SOURCE
* P_UNPLUG_REMOTE
*/
/*
* commands with out-of-struct payload:
* P_BITMAP (no additional fields)
* P_DATA, P_DATA_REPLY (see p_data)
* P_COMPRESSED_BITMAP (see receive_compressed_bitmap)
*/
/* these defines must not be changed without changing the protocol version */
#define DP_HARDBARRIER 1
#define DP_RW_SYNC 2
#define DP_MAY_SET_IN_SYNC 4
struct p_data {
struct p_header head;
u64 sector; /* 64 bits sector number */
u64 block_id; /* to identify the request in protocol B&C */
u32 seq_num;
u32 dp_flags;
} __packed;
/*
* commands which share a struct:
* p_block_ack:
* P_RECV_ACK (proto B), P_WRITE_ACK (proto C),
* P_DISCARD_ACK (proto C, two-primaries conflict detection)
* p_block_req:
* P_DATA_REQUEST, P_RS_DATA_REQUEST
*/
struct p_block_ack {
struct p_header head;
u64 sector;
u64 block_id;
u32 blksize;
u32 seq_num;
} __packed;
struct p_block_req {
struct p_header head;
u64 sector;
u64 block_id;
u32 blksize;
u32 pad; /* to multiple of 8 Byte */
} __packed;
/*
* commands with their own struct for additional fields:
* P_HAND_SHAKE
* P_BARRIER
* P_BARRIER_ACK
* P_SYNC_PARAM
* ReportParams
*/
struct p_handshake {
struct p_header head; /* 8 bytes */
u32 protocol_min;
u32 feature_flags;
u32 protocol_max;
/* should be more than enough for future enhancements
* for now, feature_flags and the reserverd array shall be zero.
*/
u32 _pad;
u64 reserverd[7];
} __packed;
/* 80 bytes, FIXED for the next century */
struct p_barrier {
struct p_header head;
u32 barrier; /* barrier number _handle_ only */
u32 pad; /* to multiple of 8 Byte */
} __packed;
struct p_barrier_ack {
struct p_header head;
u32 barrier;
u32 set_size;
} __packed;
struct p_rs_param {
struct p_header head;
u32 rate;
/* Since protocol version 88 and higher. */
char verify_alg[0];
} __packed;
struct p_rs_param_89 {
struct p_header head;
u32 rate;
/* protocol version 89: */
char verify_alg[SHARED_SECRET_MAX];
char csums_alg[SHARED_SECRET_MAX];
} __packed;
enum drbd_conn_flags {
CF_WANT_LOSE = 1,
CF_DRY_RUN = 2,
};
struct p_protocol {
struct p_header head;
u32 protocol;
u32 after_sb_0p;
u32 after_sb_1p;
u32 after_sb_2p;
u32 conn_flags;
u32 two_primaries;
/* Since protocol version 87 and higher. */
char integrity_alg[0];
} __packed;
struct p_uuids {
struct p_header head;
u64 uuid[UI_EXTENDED_SIZE];
} __packed;
struct p_rs_uuid {
struct p_header head;
u64 uuid;
} __packed;
struct p_sizes {
struct p_header head;
u64 d_size; /* size of disk */
u64 u_size; /* user requested size */
u64 c_size; /* current exported size */
u32 max_segment_size; /* Maximal size of a BIO */
u16 queue_order_type; /* not yet implemented in DRBD*/
u16 dds_flags; /* use enum dds_flags here. */
} __packed;
struct p_state {
struct p_header head;
u32 state;
} __packed;
struct p_req_state {
struct p_header head;
u32 mask;
u32 val;
} __packed;
struct p_req_state_reply {
struct p_header head;
u32 retcode;
} __packed;
struct p_drbd06_param {
u64 size;
u32 state;
u32 blksize;
u32 protocol;
u32 version;
u32 gen_cnt[5];
u32 bit_map_gen[5];
} __packed;
struct p_discard {
struct p_header head;
u64 block_id;
u32 seq_num;
u32 pad;
} __packed;
/* Valid values for the encoding field.
* Bump proto version when changing this. */
enum drbd_bitmap_code {
/* RLE_VLI_Bytes = 0,
* and other bit variants had been defined during
* algorithm evaluation. */
RLE_VLI_Bits = 2,
};
struct p_compressed_bm {
struct p_header head;
/* (encoding & 0x0f): actual encoding, see enum drbd_bitmap_code
* (encoding & 0x80): polarity (set/unset) of first runlength
* ((encoding >> 4) & 0x07): pad_bits, number of trailing zero bits
* used to pad up to head.length bytes
*/
u8 encoding;
u8 code[0];
} __packed;
struct p_delay_probe {
struct p_header head;
u32 seq_num; /* sequence number to match the two probe packets */
u32 offset; /* usecs the probe got sent after the reference time point */
} __packed;
/* DCBP: Drbd Compressed Bitmap Packet ... */
static inline enum drbd_bitmap_code
DCBP_get_code(struct p_compressed_bm *p)
{
return (enum drbd_bitmap_code)(p->encoding & 0x0f);
}
static inline void
DCBP_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code)
{
BUG_ON(code & ~0xf);
p->encoding = (p->encoding & ~0xf) | code;
}
static inline int
DCBP_get_start(struct p_compressed_bm *p)
{
return (p->encoding & 0x80) != 0;
}
static inline void
DCBP_set_start(struct p_compressed_bm *p, int set)
{
p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0);
}
static inline int
DCBP_get_pad_bits(struct p_compressed_bm *p)
{
return (p->encoding >> 4) & 0x7;
}
static inline void
DCBP_set_pad_bits(struct p_compressed_bm *p, int n)
{
BUG_ON(n & ~0x7);
p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4);
}
/* one bitmap packet, including the p_header,
* should fit within one _architecture independend_ page.
* so we need to use the fixed size 4KiB page size
* most architechtures have used for a long time.
*/
#define BM_PACKET_PAYLOAD_BYTES (4096 - sizeof(struct p_header))
#define BM_PACKET_WORDS (BM_PACKET_PAYLOAD_BYTES/sizeof(long))
#define BM_PACKET_VLI_BYTES_MAX (4096 - sizeof(struct p_compressed_bm))
#if (PAGE_SIZE < 4096)
/* drbd_send_bitmap / receive_bitmap would break horribly */
#error "PAGE_SIZE too small"
#endif
union p_polymorph {
struct p_header header;
struct p_handshake handshake;
struct p_data data;
struct p_block_ack block_ack;
struct p_barrier barrier;
struct p_barrier_ack barrier_ack;
struct p_rs_param_89 rs_param_89;
struct p_protocol protocol;
struct p_sizes sizes;
struct p_uuids uuids;
struct p_state state;
struct p_req_state req_state;
struct p_req_state_reply req_state_reply;
struct p_block_req block_req;
} __packed;
/**********************************************************************/
enum drbd_thread_state {
None,
Running,
Exiting,
Restarting
};
struct drbd_thread {
spinlock_t t_lock;
struct task_struct *task;
struct completion stop;
enum drbd_thread_state t_state;
int (*function) (struct drbd_thread *);
struct drbd_conf *mdev;
int reset_cpu_mask;
};
static inline enum drbd_thread_state get_t_state(struct drbd_thread *thi)
{
/* THINK testing the t_state seems to be uncritical in all cases
* (but thread_{start,stop}), so we can read it *without* the lock.
* --lge */
smp_rmb();
return thi->t_state;
}
/*
* Having this as the first member of a struct provides sort of "inheritance".
* "derived" structs can be "drbd_queue_work()"ed.
* The callback should know and cast back to the descendant struct.
* drbd_request and drbd_epoch_entry are descendants of drbd_work.
*/
struct drbd_work;
typedef int (*drbd_work_cb)(struct drbd_conf *, struct drbd_work *, int cancel);
struct drbd_work {
struct list_head list;
drbd_work_cb cb;
};
struct drbd_tl_epoch;
struct drbd_request {
struct drbd_work w;
struct drbd_conf *mdev;
/* if local IO is not allowed, will be NULL.
* if local IO _is_ allowed, holds the locally submitted bio clone,
* or, after local IO completion, the ERR_PTR(error).
* see drbd_endio_pri(). */
struct bio *private_bio;
struct hlist_node colision;
sector_t sector;
unsigned int size;
unsigned int epoch; /* barrier_nr */
/* barrier_nr: used to check on "completion" whether this req was in
* the current epoch, and we therefore have to close it,
* starting a new epoch...
*/
/* up to here, the struct layout is identical to drbd_epoch_entry;
* we might be able to use that to our advantage... */
struct list_head tl_requests; /* ring list in the transfer log */
struct bio *master_bio; /* master bio pointer */
unsigned long rq_state; /* see comments above _req_mod() */
int seq_num;
unsigned long start_time;
};
struct drbd_tl_epoch {
struct drbd_work w;
struct list_head requests; /* requests before */
struct drbd_tl_epoch *next; /* pointer to the next barrier */
unsigned int br_number; /* the barriers identifier. */
int n_req; /* number of requests attached before this barrier */
};
struct drbd_request;
/* These Tl_epoch_entries may be in one of 6 lists:
active_ee .. data packet being written
sync_ee .. syncer block being written
done_ee .. block written, need to send P_WRITE_ACK
read_ee .. [RS]P_DATA_REQUEST being read
*/
struct drbd_epoch {
struct list_head list;
unsigned int barrier_nr;
atomic_t epoch_size; /* increased on every request added. */
atomic_t active; /* increased on every req. added, and dec on every finished. */
unsigned long flags;
};
/* drbd_epoch flag bits */
enum {
DE_BARRIER_IN_NEXT_EPOCH_ISSUED,
DE_BARRIER_IN_NEXT_EPOCH_DONE,
DE_CONTAINS_A_BARRIER,
DE_HAVE_BARRIER_NUMBER,
DE_IS_FINISHING,
};
enum epoch_event {
EV_PUT,
EV_GOT_BARRIER_NR,
EV_BARRIER_DONE,
EV_BECAME_LAST,
EV_CLEANUP = 32, /* used as flag */
};
struct drbd_wq_barrier {
struct drbd_work w;
struct completion done;
};
struct digest_info {
int digest_size;
void *digest;
};
struct drbd_epoch_entry {
struct drbd_work w;
struct hlist_node colision;
struct drbd_epoch *epoch;
struct drbd_conf *mdev;
struct page *pages;
atomic_t pending_bios;
unsigned int size;
/* see comments on ee flag bits below */
unsigned long flags;
sector_t sector;
u64 block_id;
};
/* ee flag bits.
* While corresponding bios are in flight, the only modification will be
* set_bit WAS_ERROR, which has to be atomic.
* If no bios are in flight yet, or all have been completed,
* non-atomic modification to ee->flags is ok.
*/
enum {
__EE_CALL_AL_COMPLETE_IO,
__EE_MAY_SET_IN_SYNC,
/* This epoch entry closes an epoch using a barrier.
* On sucessful completion, the epoch is released,
* and the P_BARRIER_ACK send. */
__EE_IS_BARRIER,
/* In case a barrier failed,
* we need to resubmit without the barrier flag. */
__EE_RESUBMITTED,
/* we may have several bios per epoch entry.
* if any of those fail, we set this flag atomically
* from the endio callback */
__EE_WAS_ERROR,
};
#define EE_CALL_AL_COMPLETE_IO (1<<__EE_CALL_AL_COMPLETE_IO)
#define EE_MAY_SET_IN_SYNC (1<<__EE_MAY_SET_IN_SYNC)
#define EE_IS_BARRIER (1<<__EE_IS_BARRIER)
#define EE_RESUBMITTED (1<<__EE_RESUBMITTED)
#define EE_WAS_ERROR (1<<__EE_WAS_ERROR)
/* global flag bits */
enum {
CREATE_BARRIER, /* next P_DATA is preceeded by a P_BARRIER */
SIGNAL_ASENDER, /* whether asender wants to be interrupted */
SEND_PING, /* whether asender should send a ping asap */
STOP_SYNC_TIMER, /* tell timer to cancel itself */
UNPLUG_QUEUED, /* only relevant with kernel 2.4 */
UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */
MD_DIRTY, /* current uuids and flags not yet on disk */
DISCARD_CONCURRENT, /* Set on one node, cleared on the peer! */
USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */
CLUSTER_ST_CHANGE, /* Cluster wide state change going on... */
CL_ST_CHG_SUCCESS,
CL_ST_CHG_FAIL,
CRASHED_PRIMARY, /* This node was a crashed primary.
* Gets cleared when the state.conn
* goes into C_CONNECTED state. */
WRITE_BM_AFTER_RESYNC, /* A kmalloc() during resync failed */
NO_BARRIER_SUPP, /* underlying block device doesn't implement barriers */
CONSIDER_RESYNC,
MD_NO_BARRIER, /* meta data device does not support barriers,
so don't even try */
SUSPEND_IO, /* suspend application io */
BITMAP_IO, /* suspend application io;
once no more io in flight, start bitmap io */
BITMAP_IO_QUEUED, /* Started bitmap IO */
RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */
NET_CONGESTED, /* The data socket is congested */
CONFIG_PENDING, /* serialization of (re)configuration requests.
* if set, also prevents the device from dying */
DEVICE_DYING, /* device became unconfigured,
* but worker thread is still handling the cleanup.
* reconfiguring (nl_disk_conf, nl_net_conf) is dissalowed,
* while this is set. */
RESIZE_PENDING, /* Size change detected locally, waiting for the response from
* the peer, if it changed there as well. */
CONN_DRY_RUN, /* Expect disconnect after resync handshake. */
GOT_PING_ACK, /* set when we receive a ping_ack packet, misc wait gets woken */
};
struct drbd_bitmap; /* opaque for drbd_conf */
/* TODO sort members for performance
* MAYBE group them further */
/* THINK maybe we actually want to use the default "event/%s" worker threads
* or similar in linux 2.6, which uses per cpu data and threads.
*
* To be general, this might need a spin_lock member.
* For now, please use the mdev->req_lock to protect list_head,
* see drbd_queue_work below.
*/
struct drbd_work_queue {
struct list_head q;
struct semaphore s; /* producers up it, worker down()s it */
spinlock_t q_lock; /* to protect the list. */
};
struct drbd_socket {
struct drbd_work_queue work;
struct mutex mutex;
struct socket *socket;
/* this way we get our
* send/receive buffers off the stack */
union p_polymorph sbuf;
union p_polymorph rbuf;
};
struct drbd_md {
u64 md_offset; /* sector offset to 'super' block */
u64 la_size_sect; /* last agreed size, unit sectors */
u64 uuid[UI_SIZE];
u64 device_uuid;
u32 flags;
u32 md_size_sect;
s32 al_offset; /* signed relative sector offset to al area */
s32 bm_offset; /* signed relative sector offset to bitmap */
/* u32 al_nr_extents; important for restoring the AL
* is stored into sync_conf.al_extents, which in turn
* gets applied to act_log->nr_elements
*/
};
/* for sync_conf and other types... */
#define NL_PACKET(name, number, fields) struct name { fields };
#define NL_INTEGER(pn,pr,member) int member;
#define NL_INT64(pn,pr,member) __u64 member;
#define NL_BIT(pn,pr,member) unsigned member:1;
#define NL_STRING(pn,pr,member,len) unsigned char member[len]; int member ## _len;
#include "linux/drbd_nl.h"
struct drbd_backing_dev {
struct block_device *backing_bdev;
struct block_device *md_bdev;
struct file *lo_file;
struct file *md_file;
struct drbd_md md;
struct disk_conf dc; /* The user provided config... */
sector_t known_size; /* last known size of that backing device */
};
struct drbd_md_io {
struct drbd_conf *mdev;
struct completion event;
int error;
};
struct bm_io_work {
struct drbd_work w;
char *why;
int (*io_fn)(struct drbd_conf *mdev);
void (*done)(struct drbd_conf *mdev, int rv);
};
enum write_ordering_e {
WO_none,
WO_drain_io,
WO_bdev_flush,
WO_bio_barrier
};
struct drbd_conf {
/* things that are stored as / read from meta data on disk */
unsigned long flags;
/* configured by drbdsetup */
struct net_conf *net_conf; /* protected by get_net_conf() and put_net_conf() */
struct syncer_conf sync_conf;
struct drbd_backing_dev *ldev __protected_by(local);
sector_t p_size; /* partner's disk size */
struct request_queue *rq_queue;
struct block_device *this_bdev;
struct gendisk *vdisk;
struct drbd_socket data; /* data/barrier/cstate/parameter packets */
struct drbd_socket meta; /* ping/ack (metadata) packets */
int agreed_pro_version; /* actually used protocol version */
unsigned long last_received; /* in jiffies, either socket */
unsigned int ko_count;
struct drbd_work resync_work,
unplug_work,
md_sync_work;
struct timer_list resync_timer;
struct timer_list md_sync_timer;
/* Used after attach while negotiating new disk state. */
union drbd_state new_state_tmp;
union drbd_state state;
wait_queue_head_t misc_wait;
wait_queue_head_t state_wait; /* upon each state change. */
unsigned int send_cnt;
unsigned int recv_cnt;
unsigned int read_cnt;
unsigned int writ_cnt;
unsigned int al_writ_cnt;
unsigned int bm_writ_cnt;
atomic_t ap_bio_cnt; /* Requests we need to complete */
atomic_t ap_pending_cnt; /* AP data packets on the wire, ack expected */
atomic_t rs_pending_cnt; /* RS request/data packets on the wire */
atomic_t unacked_cnt; /* Need to send replys for */
atomic_t local_cnt; /* Waiting for local completion */
atomic_t net_cnt; /* Users of net_conf */
spinlock_t req_lock;
struct drbd_tl_epoch *unused_spare_tle; /* for pre-allocation */
struct drbd_tl_epoch *newest_tle;
struct drbd_tl_epoch *oldest_tle;
struct list_head out_of_sequence_requests;
struct hlist_head *tl_hash;
unsigned int tl_hash_s;
/* blocks to sync in this run [unit BM_BLOCK_SIZE] */
unsigned long rs_total;
/* number of sync IOs that failed in this run */
unsigned long rs_failed;
/* Syncer's start time [unit jiffies] */
unsigned long rs_start;
/* cumulated time in PausedSyncX state [unit jiffies] */
unsigned long rs_paused;
/* block not up-to-date at mark [unit BM_BLOCK_SIZE] */
unsigned long rs_mark_left;
/* marks's time [unit jiffies] */
unsigned long rs_mark_time;
/* skipped because csum was equeal [unit BM_BLOCK_SIZE] */
unsigned long rs_same_csum;
/* where does the admin want us to start? (sector) */
sector_t ov_start_sector;
/* where are we now? (sector) */
sector_t ov_position;
/* Start sector of out of sync range (to merge printk reporting). */
sector_t ov_last_oos_start;
/* size of out-of-sync range in sectors. */
sector_t ov_last_oos_size;
unsigned long ov_left; /* in bits */
struct crypto_hash *csums_tfm;
struct crypto_hash *verify_tfm;
struct drbd_thread receiver;
struct drbd_thread worker;
struct drbd_thread asender;
struct drbd_bitmap *bitmap;
unsigned long bm_resync_fo; /* bit offset for drbd_bm_find_next */
/* Used to track operations of resync... */
struct lru_cache *resync;
/* Number of locked elements in resync LRU */
unsigned int resync_locked;
/* resync extent number waiting for application requests */
unsigned int resync_wenr;
int open_cnt;
u64 *p_uuid;
struct drbd_epoch *current_epoch;
spinlock_t epoch_lock;
unsigned int epochs;
enum write_ordering_e write_ordering;
struct list_head active_ee; /* IO in progress */
struct list_head sync_ee; /* IO in progress */
struct list_head done_ee; /* send ack */
struct list_head read_ee; /* IO in progress */
struct list_head net_ee; /* zero-copy network send in progress */
struct hlist_head *ee_hash; /* is proteced by req_lock! */
unsigned int ee_hash_s;
/* this one is protected by ee_lock, single thread */
struct drbd_epoch_entry *last_write_w_barrier;
int next_barrier_nr;
struct hlist_head *app_reads_hash; /* is proteced by req_lock */
struct list_head resync_reads;
atomic_t pp_in_use;
wait_queue_head_t ee_wait;
struct page *md_io_page; /* one page buffer for md_io */
struct page *md_io_tmpp; /* for logical_block_size != 512 */
struct mutex md_io_mutex; /* protects the md_io_buffer */
spinlock_t al_lock;
wait_queue_head_t al_wait;
struct lru_cache *act_log; /* activity log */
unsigned int al_tr_number;
int al_tr_cycle;
int al_tr_pos; /* position of the next transaction in the journal */
struct crypto_hash *cram_hmac_tfm;
struct crypto_hash *integrity_w_tfm; /* to be used by the worker thread */
struct crypto_hash *integrity_r_tfm; /* to be used by the receiver thread */
void *int_dig_out;
void *int_dig_in;
void *int_dig_vv;
wait_queue_head_t seq_wait;
atomic_t packet_seq;
unsigned int peer_seq;
spinlock_t peer_seq_lock;
unsigned int minor;
unsigned long comm_bm_set; /* communicated number of set bits. */
cpumask_var_t cpu_mask;
struct bm_io_work bm_io_work;
u64 ed_uuid; /* UUID of the exposed data */
struct mutex state_mutex;
char congestion_reason; /* Why we where congested... */
};
static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
{
struct drbd_conf *mdev;
mdev = minor < minor_count ? minor_table[minor] : NULL;
return mdev;
}
static inline unsigned int mdev_to_minor(struct drbd_conf *mdev)
{
return mdev->minor;
}
/* returns 1 if it was successfull,
* returns 0 if there was no data socket.
* so wherever you are going to use the data.socket, e.g. do
* if (!drbd_get_data_sock(mdev))
* return 0;
* CODE();
* drbd_put_data_sock(mdev);
*/
static inline int drbd_get_data_sock(struct drbd_conf *mdev)
{
mutex_lock(&mdev->data.mutex);
/* drbd_disconnect() could have called drbd_free_sock()
* while we were waiting in down()... */
if (unlikely(mdev->data.socket == NULL)) {
mutex_unlock(&mdev->data.mutex);
return 0;
}
return 1;
}
static inline void drbd_put_data_sock(struct drbd_conf *mdev)
{
mutex_unlock(&mdev->data.mutex);
}
/*
* function declarations
*************************/
/* drbd_main.c */
enum chg_state_flags {
CS_HARD = 1,
CS_VERBOSE = 2,
CS_WAIT_COMPLETE = 4,
CS_SERIALIZE = 8,
CS_ORDERED = CS_WAIT_COMPLETE + CS_SERIALIZE,
};
enum dds_flags {
DDSF_FORCED = 1,
DDSF_NO_RESYNC = 2, /* Do not run a resync for the new space */
};
extern void drbd_init_set_defaults(struct drbd_conf *mdev);
extern int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
union drbd_state mask, union drbd_state val);
extern void drbd_force_state(struct drbd_conf *, union drbd_state,
union drbd_state);
extern int _drbd_request_state(struct drbd_conf *, union drbd_state,
union drbd_state, enum chg_state_flags);
extern int __drbd_set_state(struct drbd_conf *, union drbd_state,
enum chg_state_flags, struct completion *done);
extern void print_st_err(struct drbd_conf *, union drbd_state,
union drbd_state, int);
extern int drbd_thread_start(struct drbd_thread *thi);
extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait);
#ifdef CONFIG_SMP
extern void drbd_thread_current_set_cpu(struct drbd_conf *mdev);
extern void drbd_calc_cpu_mask(struct drbd_conf *mdev);
#else
#define drbd_thread_current_set_cpu(A) ({})
#define drbd_calc_cpu_mask(A) ({})
#endif
extern void drbd_free_resources(struct drbd_conf *mdev);
extern void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
unsigned int set_size);
extern void tl_clear(struct drbd_conf *mdev);
extern void _tl_add_barrier(struct drbd_conf *, struct drbd_tl_epoch *);
extern void drbd_free_sock(struct drbd_conf *mdev);
extern int drbd_send(struct drbd_conf *mdev, struct socket *sock,
void *buf, size_t size, unsigned msg_flags);
extern int drbd_send_protocol(struct drbd_conf *mdev);
extern int drbd_send_uuids(struct drbd_conf *mdev);
extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev);
extern int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val);
extern int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags);
extern int _drbd_send_state(struct drbd_conf *mdev);
extern int drbd_send_state(struct drbd_conf *mdev);
extern int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
enum drbd_packets cmd, struct p_header *h,
size_t size, unsigned msg_flags);
#define USE_DATA_SOCKET 1
#define USE_META_SOCKET 0
extern int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
enum drbd_packets cmd, struct p_header *h,
size_t size);
extern int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd,
char *data, size_t size);
extern int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc);
extern int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr,
u32 set_size);
extern int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
struct drbd_epoch_entry *e);
extern int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
struct p_block_req *rp);
extern int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
struct p_data *dp);
extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
sector_t sector, int blksize, u64 block_id);
extern int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
struct drbd_epoch_entry *e);
extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req);
extern int _drbd_send_barrier(struct drbd_conf *mdev,
struct drbd_tl_epoch *barrier);
extern int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
sector_t sector, int size, u64 block_id);
extern int drbd_send_drequest_csum(struct drbd_conf *mdev,
sector_t sector,int size,
void *digest, int digest_size,
enum drbd_packets cmd);
extern int drbd_send_ov_request(struct drbd_conf *mdev,sector_t sector,int size);
extern int drbd_send_bitmap(struct drbd_conf *mdev);
extern int _drbd_send_bitmap(struct drbd_conf *mdev);
extern int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode);
extern void drbd_free_bc(struct drbd_backing_dev *ldev);
extern void drbd_mdev_cleanup(struct drbd_conf *mdev);
/* drbd_meta-data.c (still in drbd_main.c) */
extern void drbd_md_sync(struct drbd_conf *mdev);
extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev);
/* maybe define them below as inline? */
extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
extern void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
extern void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
extern void _drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local);
extern void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local);
extern void drbd_md_set_flag(struct drbd_conf *mdev, int flags) __must_hold(local);
extern void drbd_md_clear_flag(struct drbd_conf *mdev, int flags)__must_hold(local);
extern int drbd_md_test_flag(struct drbd_backing_dev *, int);
extern void drbd_md_mark_dirty(struct drbd_conf *mdev);
extern void drbd_queue_bitmap_io(struct drbd_conf *mdev,
int (*io_fn)(struct drbd_conf *),
void (*done)(struct drbd_conf *, int),
char *why);
extern int drbd_bmio_set_n_write(struct drbd_conf *mdev);
extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev);
extern int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why);
/* Meta data layout
We reserve a 128MB Block (4k aligned)
* either at the end of the backing device
* or on a separate meta data device. */
#define MD_RESERVED_SECT (128LU << 11) /* 128 MB, unit sectors */
/* The following numbers are sectors */
#define MD_AL_OFFSET 8 /* 8 Sectors after start of meta area */
#define MD_AL_MAX_SIZE 64 /* = 32 kb LOG ~ 3776 extents ~ 14 GB Storage */
/* Allows up to about 3.8TB */
#define MD_BM_OFFSET (MD_AL_OFFSET + MD_AL_MAX_SIZE)
/* Since the smalles IO unit is usually 512 byte */
#define MD_SECTOR_SHIFT 9
#define MD_SECTOR_SIZE (1<<MD_SECTOR_SHIFT)
/* activity log */
#define AL_EXTENTS_PT ((MD_SECTOR_SIZE-12)/8-1) /* 61 ; Extents per 512B sector */
#define AL_EXTENT_SHIFT 22 /* One extent represents 4M Storage */
#define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT)
#if BITS_PER_LONG == 32
#define LN2_BPL 5
#define cpu_to_lel(A) cpu_to_le32(A)
#define lel_to_cpu(A) le32_to_cpu(A)
#elif BITS_PER_LONG == 64
#define LN2_BPL 6
#define cpu_to_lel(A) cpu_to_le64(A)
#define lel_to_cpu(A) le64_to_cpu(A)
#else
#error "LN2 of BITS_PER_LONG unknown!"
#endif
/* resync bitmap */
/* 16MB sized 'bitmap extent' to track syncer usage */
struct bm_extent {
int rs_left; /* number of bits set (out of sync) in this extent. */
int rs_failed; /* number of failed resync requests in this extent. */
unsigned long flags;
struct lc_element lce;
};
#define BME_NO_WRITES 0 /* bm_extent.flags: no more requests on this one! */
#define BME_LOCKED 1 /* bm_extent.flags: syncer active on this one. */
/* drbd_bitmap.c */
/*
* We need to store one bit for a block.
* Example: 1GB disk @ 4096 byte blocks ==> we need 32 KB bitmap.
* Bit 0 ==> local node thinks this block is binary identical on both nodes
* Bit 1 ==> local node thinks this block needs to be synced.
*/
#define BM_BLOCK_SHIFT 12 /* 4k per bit */
#define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT)
/* (9+3) : 512 bytes @ 8 bits; representing 16M storage
* per sector of on disk bitmap */
#define BM_EXT_SHIFT (BM_BLOCK_SHIFT + MD_SECTOR_SHIFT + 3) /* = 24 */
#define BM_EXT_SIZE (1<<BM_EXT_SHIFT)
#if (BM_EXT_SHIFT != 24) || (BM_BLOCK_SHIFT != 12)
#error "HAVE YOU FIXED drbdmeta AS WELL??"
#endif
/* thus many _storage_ sectors are described by one bit */
#define BM_SECT_TO_BIT(x) ((x)>>(BM_BLOCK_SHIFT-9))
#define BM_BIT_TO_SECT(x) ((sector_t)(x)<<(BM_BLOCK_SHIFT-9))
#define BM_SECT_PER_BIT BM_BIT_TO_SECT(1)
/* bit to represented kilo byte conversion */
#define Bit2KB(bits) ((bits)<<(BM_BLOCK_SHIFT-10))
/* in which _bitmap_ extent (resp. sector) the bit for a certain
* _storage_ sector is located in */
#define BM_SECT_TO_EXT(x) ((x)>>(BM_EXT_SHIFT-9))
/* how much _storage_ sectors we have per bitmap sector */
#define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9))
#define BM_SECT_PER_EXT BM_EXT_TO_SECT(1)
/* in one sector of the bitmap, we have this many activity_log extents. */
#define AL_EXT_PER_BM_SECT (1 << (BM_EXT_SHIFT - AL_EXTENT_SHIFT))
#define BM_WORDS_PER_AL_EXT (1 << (AL_EXTENT_SHIFT-BM_BLOCK_SHIFT-LN2_BPL))
#define BM_BLOCKS_PER_BM_EXT_B (BM_EXT_SHIFT - BM_BLOCK_SHIFT)
#define BM_BLOCKS_PER_BM_EXT_MASK ((1<<BM_BLOCKS_PER_BM_EXT_B) - 1)
/* the extent in "PER_EXTENT" below is an activity log extent
* we need that many (long words/bytes) to store the bitmap
* of one AL_EXTENT_SIZE chunk of storage.
* we can store the bitmap for that many AL_EXTENTS within
* one sector of the _on_disk_ bitmap:
* bit 0 bit 37 bit 38 bit (512*8)-1
* ...|........|........|.. // ..|........|
* sect. 0 `296 `304 ^(512*8*8)-1
*
#define BM_WORDS_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / BITS_PER_LONG )
#define BM_BYTES_PER_EXT ( (AL_EXT_SIZE/BM_BLOCK_SIZE) / 8 ) // 128
#define BM_EXT_PER_SECT ( 512 / BM_BYTES_PER_EXTENT ) // 4
*/
#define DRBD_MAX_SECTORS_32 (0xffffffffLU)
#define DRBD_MAX_SECTORS_BM \
((MD_RESERVED_SECT - MD_BM_OFFSET) * (1LL<<(BM_EXT_SHIFT-9)))
#if DRBD_MAX_SECTORS_BM < DRBD_MAX_SECTORS_32
#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
#define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_BM
#elif !defined(CONFIG_LBDAF) && BITS_PER_LONG == 32
#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_32
#define DRBD_MAX_SECTORS_FLEX DRBD_MAX_SECTORS_32
#else
#define DRBD_MAX_SECTORS DRBD_MAX_SECTORS_BM
/* 16 TB in units of sectors */
#if BITS_PER_LONG == 32
/* adjust by one page worth of bitmap,
* so we won't wrap around in drbd_bm_find_next_bit.
* you should use 64bit OS for that much storage, anyways. */
#define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0xffff7fff)
#else
#define DRBD_MAX_SECTORS_FLEX BM_BIT_TO_SECT(0x1LU << 32)
#endif
#endif
/* Sector shift value for the "hash" functions of tl_hash and ee_hash tables.
* With a value of 6 all IO in one 32K block make it to the same slot of the
* hash table. */
#define HT_SHIFT 6
#define DRBD_MAX_SEGMENT_SIZE (1U<<(9+HT_SHIFT))
/* Number of elements in the app_reads_hash */
#define APP_R_HSIZE 15
extern int drbd_bm_init(struct drbd_conf *mdev);
extern int drbd_bm_resize(struct drbd_conf *mdev, sector_t sectors, int set_new_bits);
extern void drbd_bm_cleanup(struct drbd_conf *mdev);
extern void drbd_bm_set_all(struct drbd_conf *mdev);
extern void drbd_bm_clear_all(struct drbd_conf *mdev);
extern int drbd_bm_set_bits(
struct drbd_conf *mdev, unsigned long s, unsigned long e);
extern int drbd_bm_clear_bits(
struct drbd_conf *mdev, unsigned long s, unsigned long e);
/* bm_set_bits variant for use while holding drbd_bm_lock */
extern void _drbd_bm_set_bits(struct drbd_conf *mdev,
const unsigned long s, const unsigned long e);
extern int drbd_bm_test_bit(struct drbd_conf *mdev, unsigned long bitnr);
extern int drbd_bm_e_weight(struct drbd_conf *mdev, unsigned long enr);
extern int drbd_bm_write_sect(struct drbd_conf *mdev, unsigned long enr) __must_hold(local);
extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local);
extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local);
extern unsigned long drbd_bm_ALe_set_all(struct drbd_conf *mdev,
unsigned long al_enr);
extern size_t drbd_bm_words(struct drbd_conf *mdev);
extern unsigned long drbd_bm_bits(struct drbd_conf *mdev);
extern sector_t drbd_bm_capacity(struct drbd_conf *mdev);
extern unsigned long drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
/* bm_find_next variants for use while you hold drbd_bm_lock() */
extern unsigned long _drbd_bm_find_next(struct drbd_conf *mdev, unsigned long bm_fo);
extern unsigned long _drbd_bm_find_next_zero(struct drbd_conf *mdev, unsigned long bm_fo);
extern unsigned long drbd_bm_total_weight(struct drbd_conf *mdev);
extern int drbd_bm_rs_done(struct drbd_conf *mdev);
/* for receive_bitmap */
extern void drbd_bm_merge_lel(struct drbd_conf *mdev, size_t offset,
size_t number, unsigned long *buffer);
/* for _drbd_send_bitmap and drbd_bm_write_sect */
extern void drbd_bm_get_lel(struct drbd_conf *mdev, size_t offset,
size_t number, unsigned long *buffer);
extern void drbd_bm_lock(struct drbd_conf *mdev, char *why);
extern void drbd_bm_unlock(struct drbd_conf *mdev);
extern int drbd_bm_count_bits(struct drbd_conf *mdev, const unsigned long s, const unsigned long e);
/* drbd_main.c */
extern struct kmem_cache *drbd_request_cache;
extern struct kmem_cache *drbd_ee_cache; /* epoch entries */
extern struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */
extern struct kmem_cache *drbd_al_ext_cache; /* activity log extents */
extern mempool_t *drbd_request_mempool;
extern mempool_t *drbd_ee_mempool;
extern struct page *drbd_pp_pool; /* drbd's page pool */
extern spinlock_t drbd_pp_lock;
extern int drbd_pp_vacant;
extern wait_queue_head_t drbd_pp_wait;
extern rwlock_t global_state_lock;
extern struct drbd_conf *drbd_new_device(unsigned int minor);
extern void drbd_free_mdev(struct drbd_conf *mdev);
extern int proc_details;
/* drbd_req */
extern int drbd_make_request_26(struct request_queue *q, struct bio *bio);
extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req);
extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec);
extern int is_valid_ar_handle(struct drbd_request *, sector_t);
/* drbd_nl.c */
extern void drbd_suspend_io(struct drbd_conf *mdev);
extern void drbd_resume_io(struct drbd_conf *mdev);
extern char *ppsize(char *buf, unsigned long long size);
extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, int);
enum determine_dev_size { dev_size_error = -1, unchanged = 0, shrunk = 1, grew = 2 };
extern enum determine_dev_size drbd_determin_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local);
extern void resync_after_online_grow(struct drbd_conf *);
extern void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int) __must_hold(local);
extern int drbd_set_role(struct drbd_conf *mdev, enum drbd_role new_role,
int force);
enum drbd_disk_state drbd_try_outdate_peer(struct drbd_conf *mdev);
extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
/* drbd_worker.c */
extern int drbd_worker(struct drbd_thread *thi);
extern int drbd_alter_sa(struct drbd_conf *mdev, int na);
extern void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side);
extern void resume_next_sg(struct drbd_conf *mdev);
extern void suspend_other_sg(struct drbd_conf *mdev);
extern int drbd_resync_finished(struct drbd_conf *mdev);
/* maybe rather drbd_main.c ? */
extern int drbd_md_sync_page_io(struct drbd_conf *mdev,
struct drbd_backing_dev *bdev, sector_t sector, int rw);
extern void drbd_ov_oos_found(struct drbd_conf*, sector_t, int);
static inline void ov_oos_print(struct drbd_conf *mdev)
{
if (mdev->ov_last_oos_size) {
dev_err(DEV, "Out of sync: start=%llu, size=%lu (sectors)\n",
(unsigned long long)mdev->ov_last_oos_start,
(unsigned long)mdev->ov_last_oos_size);
}
mdev->ov_last_oos_size=0;
}
extern void drbd_csum_bio(struct drbd_conf *, struct crypto_hash *, struct bio *, void *);
extern void drbd_csum_ee(struct drbd_conf *, struct crypto_hash *, struct drbd_epoch_entry *, void *);
/* worker callbacks */
extern int w_req_cancel_conflict(struct drbd_conf *, struct drbd_work *, int);
extern int w_read_retry_remote(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_end_data_req(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_end_rsdata_req(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_end_csum_rs_req(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_end_ov_reply(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_end_ov_req(struct drbd_conf *, struct drbd_work *, int);
extern int w_ov_finished(struct drbd_conf *, struct drbd_work *, int);
extern int w_resync_inactive(struct drbd_conf *, struct drbd_work *, int);
extern int w_resume_next_sg(struct drbd_conf *, struct drbd_work *, int);
extern int w_send_write_hint(struct drbd_conf *, struct drbd_work *, int);
extern int w_make_resync_request(struct drbd_conf *, struct drbd_work *, int);
extern int w_send_dblock(struct drbd_conf *, struct drbd_work *, int);
extern int w_send_barrier(struct drbd_conf *, struct drbd_work *, int);
extern int w_send_read_req(struct drbd_conf *, struct drbd_work *, int);
extern int w_prev_work_done(struct drbd_conf *, struct drbd_work *, int);
extern int w_e_reissue(struct drbd_conf *, struct drbd_work *, int);
extern void resync_timer_fn(unsigned long data);
/* drbd_receiver.c */
extern int drbd_submit_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e,
const unsigned rw, const int fault_type);
extern int drbd_release_ee(struct drbd_conf *mdev, struct list_head *list);
extern struct drbd_epoch_entry *drbd_alloc_ee(struct drbd_conf *mdev,
u64 id,
sector_t sector,
unsigned int data_size,
gfp_t gfp_mask) __must_hold(local);
extern void drbd_free_ee(struct drbd_conf *mdev, struct drbd_epoch_entry *e);
extern void drbd_wait_ee_list_empty(struct drbd_conf *mdev,
struct list_head *head);
extern void _drbd_wait_ee_list_empty(struct drbd_conf *mdev,
struct list_head *head);
extern void drbd_set_recv_tcq(struct drbd_conf *mdev, int tcq_enabled);
extern void _drbd_clear_done_ee(struct drbd_conf *mdev, struct list_head *to_be_freed);
extern void drbd_flush_workqueue(struct drbd_conf *mdev);
/* yes, there is kernel_setsockopt, but only since 2.6.18. we don't need to
* mess with get_fs/set_fs, we know we are KERNEL_DS always. */
static inline int drbd_setsockopt(struct socket *sock, int level, int optname,
char __user *optval, int optlen)
{
int err;
if (level == SOL_SOCKET)
err = sock_setsockopt(sock, level, optname, optval, optlen);
else
err = sock->ops->setsockopt(sock, level, optname, optval,
optlen);
return err;
}
static inline void drbd_tcp_cork(struct socket *sock)
{
int __user val = 1;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
(char __user *)&val, sizeof(val));
}
static inline void drbd_tcp_uncork(struct socket *sock)
{
int __user val = 0;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
(char __user *)&val, sizeof(val));
}
static inline void drbd_tcp_nodelay(struct socket *sock)
{
int __user val = 1;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY,
(char __user *)&val, sizeof(val));
}
static inline void drbd_tcp_quickack(struct socket *sock)
{
int __user val = 2;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK,
(char __user *)&val, sizeof(val));
}
void drbd_bump_write_ordering(struct drbd_conf *mdev, enum write_ordering_e wo);
/* drbd_proc.c */
extern struct proc_dir_entry *drbd_proc;
extern const struct file_operations drbd_proc_fops;
extern const char *drbd_conn_str(enum drbd_conns s);
extern const char *drbd_role_str(enum drbd_role s);
/* drbd_actlog.c */
extern void drbd_al_begin_io(struct drbd_conf *mdev, sector_t sector);
extern void drbd_al_complete_io(struct drbd_conf *mdev, sector_t sector);
extern void drbd_rs_complete_io(struct drbd_conf *mdev, sector_t sector);
extern int drbd_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
extern int drbd_try_rs_begin_io(struct drbd_conf *mdev, sector_t sector);
extern void drbd_rs_cancel_all(struct drbd_conf *mdev);
extern int drbd_rs_del_all(struct drbd_conf *mdev);
extern void drbd_rs_failed_io(struct drbd_conf *mdev,
sector_t sector, int size);
extern int drbd_al_read_log(struct drbd_conf *mdev, struct drbd_backing_dev *);
extern void __drbd_set_in_sync(struct drbd_conf *mdev, sector_t sector,
int size, const char *file, const unsigned int line);
#define drbd_set_in_sync(mdev, sector, size) \
__drbd_set_in_sync(mdev, sector, size, __FILE__, __LINE__)
extern void __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector,
int size, const char *file, const unsigned int line);
#define drbd_set_out_of_sync(mdev, sector, size) \
__drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__)
extern void drbd_al_apply_to_bm(struct drbd_conf *mdev);
extern void drbd_al_to_on_disk_bm(struct drbd_conf *mdev);
extern void drbd_al_shrink(struct drbd_conf *mdev);
/* drbd_nl.c */
void drbd_nl_cleanup(void);
int __init drbd_nl_init(void);
void drbd_bcast_state(struct drbd_conf *mdev, union drbd_state);
void drbd_bcast_sync_progress(struct drbd_conf *mdev);
void drbd_bcast_ee(struct drbd_conf *mdev,
const char *reason, const int dgs,
const char* seen_hash, const char* calc_hash,
const struct drbd_epoch_entry* e);
/**
* DOC: DRBD State macros
*
* These macros are used to express state changes in easily readable form.
*
* The NS macros expand to a mask and a value, that can be bit ored onto the
* current state as soon as the spinlock (req_lock) was taken.
*
* The _NS macros are used for state functions that get called with the
* spinlock. These macros expand directly to the new state value.
*
* Besides the basic forms NS() and _NS() additional _?NS[23] are defined
* to express state changes that affect more than one aspect of the state.
*
* E.g. NS2(conn, C_CONNECTED, peer, R_SECONDARY)
* Means that the network connection was established and that the peer
* is in secondary role.
*/
#define role_MASK R_MASK
#define peer_MASK R_MASK
#define disk_MASK D_MASK
#define pdsk_MASK D_MASK
#define conn_MASK C_MASK
#define susp_MASK 1
#define user_isp_MASK 1
#define aftr_isp_MASK 1
#define NS(T, S) \
({ union drbd_state mask; mask.i = 0; mask.T = T##_MASK; mask; }), \
({ union drbd_state val; val.i = 0; val.T = (S); val; })
#define NS2(T1, S1, T2, S2) \
({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
mask.T2 = T2##_MASK; mask; }), \
({ union drbd_state val; val.i = 0; val.T1 = (S1); \
val.T2 = (S2); val; })
#define NS3(T1, S1, T2, S2, T3, S3) \
({ union drbd_state mask; mask.i = 0; mask.T1 = T1##_MASK; \
mask.T2 = T2##_MASK; mask.T3 = T3##_MASK; mask; }), \
({ union drbd_state val; val.i = 0; val.T1 = (S1); \
val.T2 = (S2); val.T3 = (S3); val; })
#define _NS(D, T, S) \
D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T = (S); __ns; })
#define _NS2(D, T1, S1, T2, S2) \
D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
__ns.T2 = (S2); __ns; })
#define _NS3(D, T1, S1, T2, S2, T3, S3) \
D, ({ union drbd_state __ns; __ns.i = D->state.i; __ns.T1 = (S1); \
__ns.T2 = (S2); __ns.T3 = (S3); __ns; })
/*
* inline helper functions
*************************/
/* see also page_chain_add and friends in drbd_receiver.c */
static inline struct page *page_chain_next(struct page *page)
{
return (struct page *)page_private(page);
}
#define page_chain_for_each(page) \
for (; page && ({ prefetch(page_chain_next(page)); 1; }); \
page = page_chain_next(page))
#define page_chain_for_each_safe(page, n) \
for (; page && ({ n = page_chain_next(page); 1; }); page = n)
static inline int drbd_bio_has_active_page(struct bio *bio)
{
struct bio_vec *bvec;
int i;
__bio_for_each_segment(bvec, bio, i, 0) {
if (page_count(bvec->bv_page) > 1)
return 1;
}
return 0;
}
static inline int drbd_ee_has_active_page(struct drbd_epoch_entry *e)
{
struct page *page = e->pages;
page_chain_for_each(page) {
if (page_count(page) > 1)
return 1;
}
return 0;
}
static inline void drbd_state_lock(struct drbd_conf *mdev)
{
wait_event(mdev->misc_wait,
!test_and_set_bit(CLUSTER_ST_CHANGE, &mdev->flags));
}
static inline void drbd_state_unlock(struct drbd_conf *mdev)
{
clear_bit(CLUSTER_ST_CHANGE, &mdev->flags);
wake_up(&mdev->misc_wait);
}
static inline int _drbd_set_state(struct drbd_conf *mdev,
union drbd_state ns, enum chg_state_flags flags,
struct completion *done)
{
int rv;
read_lock(&global_state_lock);
rv = __drbd_set_state(mdev, ns, flags, done);
read_unlock(&global_state_lock);
return rv;
}
/**
* drbd_request_state() - Reqest a state change
* @mdev: DRBD device.
* @mask: mask of state bits to change.
* @val: value of new state bits.
*
* This is the most graceful way of requesting a state change. It is verbose
* quite verbose in case the state change is not possible, and all those
* state changes are globally serialized.
*/
static inline int drbd_request_state(struct drbd_conf *mdev,
union drbd_state mask,
union drbd_state val)
{
return _drbd_request_state(mdev, mask, val, CS_VERBOSE + CS_ORDERED);
}
#define __drbd_chk_io_error(m,f) __drbd_chk_io_error_(m,f, __func__)
static inline void __drbd_chk_io_error_(struct drbd_conf *mdev, int forcedetach, const char *where)
{
switch (mdev->ldev->dc.on_io_error) {
case EP_PASS_ON:
if (!forcedetach) {
if (__ratelimit(&drbd_ratelimit_state))
dev_err(DEV, "Local IO failed in %s."
"Passing error on...\n", where);
break;
}
/* NOTE fall through to detach case if forcedetach set */
case EP_DETACH:
case EP_CALL_HELPER:
if (mdev->state.disk > D_FAILED) {
_drbd_set_state(_NS(mdev, disk, D_FAILED), CS_HARD, NULL);
dev_err(DEV, "Local IO failed in %s."
"Detaching...\n", where);
}
break;
}
}
/**
* drbd_chk_io_error: Handle the on_io_error setting, should be called from all io completion handlers
* @mdev: DRBD device.
* @error: Error code passed to the IO completion callback
* @forcedetach: Force detach. I.e. the error happened while accessing the meta data
*
* See also drbd_main.c:after_state_ch() if (os.disk > D_FAILED && ns.disk == D_FAILED)
*/
#define drbd_chk_io_error(m,e,f) drbd_chk_io_error_(m,e,f, __func__)
static inline void drbd_chk_io_error_(struct drbd_conf *mdev,
int error, int forcedetach, const char *where)
{
if (error) {
unsigned long flags;
spin_lock_irqsave(&mdev->req_lock, flags);
__drbd_chk_io_error_(mdev, forcedetach, where);
spin_unlock_irqrestore(&mdev->req_lock, flags);
}
}
/**
* drbd_md_first_sector() - Returns the first sector number of the meta data area
* @bdev: Meta data block device.
*
* BTW, for internal meta data, this happens to be the maximum capacity
* we could agree upon with our peer node.
*/
static inline sector_t drbd_md_first_sector(struct drbd_backing_dev *bdev)
{
switch (bdev->dc.meta_dev_idx) {
case DRBD_MD_INDEX_INTERNAL:
case DRBD_MD_INDEX_FLEX_INT:
return bdev->md.md_offset + bdev->md.bm_offset;
case DRBD_MD_INDEX_FLEX_EXT:
default:
return bdev->md.md_offset;
}
}
/**
* drbd_md_last_sector() - Return the last sector number of the meta data area
* @bdev: Meta data block device.
*/
static inline sector_t drbd_md_last_sector(struct drbd_backing_dev *bdev)
{
switch (bdev->dc.meta_dev_idx) {
case DRBD_MD_INDEX_INTERNAL:
case DRBD_MD_INDEX_FLEX_INT:
return bdev->md.md_offset + MD_AL_OFFSET - 1;
case DRBD_MD_INDEX_FLEX_EXT:
default:
return bdev->md.md_offset + bdev->md.md_size_sect;
}
}
/* Returns the number of 512 byte sectors of the device */
static inline sector_t drbd_get_capacity(struct block_device *bdev)
{
/* return bdev ? get_capacity(bdev->bd_disk) : 0; */
return bdev ? bdev->bd_inode->i_size >> 9 : 0;
}
/**
* drbd_get_max_capacity() - Returns the capacity we announce to out peer
* @bdev: Meta data block device.
*
* returns the capacity we announce to out peer. we clip ourselves at the
* various MAX_SECTORS, because if we don't, current implementation will
* oops sooner or later
*/
static inline sector_t drbd_get_max_capacity(struct drbd_backing_dev *bdev)
{
sector_t s;
switch (bdev->dc.meta_dev_idx) {
case DRBD_MD_INDEX_INTERNAL:
case DRBD_MD_INDEX_FLEX_INT:
s = drbd_get_capacity(bdev->backing_bdev)
? min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
drbd_md_first_sector(bdev))
: 0;
break;
case DRBD_MD_INDEX_FLEX_EXT:
s = min_t(sector_t, DRBD_MAX_SECTORS_FLEX,
drbd_get_capacity(bdev->backing_bdev));
/* clip at maximum size the meta device can support */
s = min_t(sector_t, s,
BM_EXT_TO_SECT(bdev->md.md_size_sect
- bdev->md.bm_offset));
break;
default:
s = min_t(sector_t, DRBD_MAX_SECTORS,
drbd_get_capacity(bdev->backing_bdev));
}
return s;
}
/**
* drbd_md_ss__() - Return the sector number of our meta data super block
* @mdev: DRBD device.
* @bdev: Meta data block device.
*/
static inline sector_t drbd_md_ss__(struct drbd_conf *mdev,
struct drbd_backing_dev *bdev)
{
switch (bdev->dc.meta_dev_idx) {
default: /* external, some index */
return MD_RESERVED_SECT * bdev->dc.meta_dev_idx;
case DRBD_MD_INDEX_INTERNAL:
/* with drbd08, internal meta data is always "flexible" */
case DRBD_MD_INDEX_FLEX_INT:
/* sizeof(struct md_on_disk_07) == 4k
* position: last 4k aligned block of 4k size */
if (!bdev->backing_bdev) {
if (__ratelimit(&drbd_ratelimit_state)) {
dev_err(DEV, "bdev->backing_bdev==NULL\n");
dump_stack();
}
return 0;
}
return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL)
- MD_AL_OFFSET;
case DRBD_MD_INDEX_FLEX_EXT:
return 0;
}
}
static inline void
_drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
{
list_add_tail(&w->list, &q->q);
up(&q->s);
}
static inline void
drbd_queue_work_front(struct drbd_work_queue *q, struct drbd_work *w)
{
unsigned long flags;
spin_lock_irqsave(&q->q_lock, flags);
list_add(&w->list, &q->q);
up(&q->s); /* within the spinlock,
see comment near end of drbd_worker() */
spin_unlock_irqrestore(&q->q_lock, flags);
}
static inline void
drbd_queue_work(struct drbd_work_queue *q, struct drbd_work *w)
{
unsigned long flags;
spin_lock_irqsave(&q->q_lock, flags);
list_add_tail(&w->list, &q->q);
up(&q->s); /* within the spinlock,
see comment near end of drbd_worker() */
spin_unlock_irqrestore(&q->q_lock, flags);
}
static inline void wake_asender(struct drbd_conf *mdev)
{
if (test_bit(SIGNAL_ASENDER, &mdev->flags))
force_sig(DRBD_SIG, mdev->asender.task);
}
static inline void request_ping(struct drbd_conf *mdev)
{
set_bit(SEND_PING, &mdev->flags);
wake_asender(mdev);
}
static inline int drbd_send_short_cmd(struct drbd_conf *mdev,
enum drbd_packets cmd)
{
struct p_header h;
return drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd, &h, sizeof(h));
}
static inline int drbd_send_ping(struct drbd_conf *mdev)
{
struct p_header h;
return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING, &h, sizeof(h));
}
static inline int drbd_send_ping_ack(struct drbd_conf *mdev)
{
struct p_header h;
return drbd_send_cmd(mdev, USE_META_SOCKET, P_PING_ACK, &h, sizeof(h));
}
static inline void drbd_thread_stop(struct drbd_thread *thi)
{
_drbd_thread_stop(thi, FALSE, TRUE);
}
static inline void drbd_thread_stop_nowait(struct drbd_thread *thi)
{
_drbd_thread_stop(thi, FALSE, FALSE);
}
static inline void drbd_thread_restart_nowait(struct drbd_thread *thi)
{
_drbd_thread_stop(thi, TRUE, FALSE);
}
/* counts how many answer packets packets we expect from our peer,
* for either explicit application requests,
* or implicit barrier packets as necessary.
* increased:
* w_send_barrier
* _req_mod(req, queue_for_net_write or queue_for_net_read);
* it is much easier and equally valid to count what we queue for the
* worker, even before it actually was queued or send.
* (drbd_make_request_common; recovery path on read io-error)
* decreased:
* got_BarrierAck (respective tl_clear, tl_clear_barrier)
* _req_mod(req, data_received)
* [from receive_DataReply]
* _req_mod(req, write_acked_by_peer or recv_acked_by_peer or neg_acked)
* [from got_BlockAck (P_WRITE_ACK, P_RECV_ACK)]
* for some reason it is NOT decreased in got_NegAck,
* but in the resulting cleanup code from report_params.
* we should try to remember the reason for that...
* _req_mod(req, send_failed or send_canceled)
* _req_mod(req, connection_lost_while_pending)
* [from tl_clear_barrier]
*/
static inline void inc_ap_pending(struct drbd_conf *mdev)
{
atomic_inc(&mdev->ap_pending_cnt);
}
#define ERR_IF_CNT_IS_NEGATIVE(which) \
if (atomic_read(&mdev->which) < 0) \
dev_err(DEV, "in %s:%d: " #which " = %d < 0 !\n", \
__func__ , __LINE__ , \
atomic_read(&mdev->which))
#define dec_ap_pending(mdev) do { \
typecheck(struct drbd_conf *, mdev); \
if (atomic_dec_and_test(&mdev->ap_pending_cnt)) \
wake_up(&mdev->misc_wait); \
ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt); } while (0)
/* counts how many resync-related answers we still expect from the peer
* increase decrease
* C_SYNC_TARGET sends P_RS_DATA_REQUEST (and expects P_RS_DATA_REPLY)
* C_SYNC_SOURCE sends P_RS_DATA_REPLY (and expects P_WRITE_ACK whith ID_SYNCER)
* (or P_NEG_ACK with ID_SYNCER)
*/
static inline void inc_rs_pending(struct drbd_conf *mdev)
{
atomic_inc(&mdev->rs_pending_cnt);
}
#define dec_rs_pending(mdev) do { \
typecheck(struct drbd_conf *, mdev); \
atomic_dec(&mdev->rs_pending_cnt); \
ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt); } while (0)
/* counts how many answers we still need to send to the peer.
* increased on
* receive_Data unless protocol A;
* we need to send a P_RECV_ACK (proto B)
* or P_WRITE_ACK (proto C)
* receive_RSDataReply (recv_resync_read) we need to send a P_WRITE_ACK
* receive_DataRequest (receive_RSDataRequest) we need to send back P_DATA
* receive_Barrier_* we need to send a P_BARRIER_ACK
*/
static inline void inc_unacked(struct drbd_conf *mdev)
{
atomic_inc(&mdev->unacked_cnt);
}
#define dec_unacked(mdev) do { \
typecheck(struct drbd_conf *, mdev); \
atomic_dec(&mdev->unacked_cnt); \
ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
#define sub_unacked(mdev, n) do { \
typecheck(struct drbd_conf *, mdev); \
atomic_sub(n, &mdev->unacked_cnt); \
ERR_IF_CNT_IS_NEGATIVE(unacked_cnt); } while (0)
static inline void put_net_conf(struct drbd_conf *mdev)
{
if (atomic_dec_and_test(&mdev->net_cnt))
wake_up(&mdev->misc_wait);
}
/**
* get_net_conf() - Increase ref count on mdev->net_conf; Returns 0 if nothing there
* @mdev: DRBD device.
*
* You have to call put_net_conf() when finished working with mdev->net_conf.
*/
static inline int get_net_conf(struct drbd_conf *mdev)
{
int have_net_conf;
atomic_inc(&mdev->net_cnt);
have_net_conf = mdev->state.conn >= C_UNCONNECTED;
if (!have_net_conf)
put_net_conf(mdev);
return have_net_conf;
}
/**
* get_ldev() - Increase the ref count on mdev->ldev. Returns 0 if there is no ldev
* @M: DRBD device.
*
* You have to call put_ldev() when finished working with mdev->ldev.
*/
#define get_ldev(M) __cond_lock(local, _get_ldev_if_state(M,D_INCONSISTENT))
#define get_ldev_if_state(M,MINS) __cond_lock(local, _get_ldev_if_state(M,MINS))
static inline void put_ldev(struct drbd_conf *mdev)
{
__release(local);
if (atomic_dec_and_test(&mdev->local_cnt))
wake_up(&mdev->misc_wait);
D_ASSERT(atomic_read(&mdev->local_cnt) >= 0);
}
#ifndef __CHECKER__
static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
{
int io_allowed;
atomic_inc(&mdev->local_cnt);
io_allowed = (mdev->state.disk >= mins);
if (!io_allowed)
put_ldev(mdev);
return io_allowed;
}
#else
extern int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins);
#endif
/* you must have an "get_ldev" reference */
static inline void drbd_get_syncer_progress(struct drbd_conf *mdev,
unsigned long *bits_left, unsigned int *per_mil_done)
{
/*
* this is to break it at compile time when we change that
* (we may feel 4TB maximum storage per drbd is not enough)
*/
typecheck(unsigned long, mdev->rs_total);
/* note: both rs_total and rs_left are in bits, i.e. in
* units of BM_BLOCK_SIZE.
* for the percentage, we don't care. */
*bits_left = drbd_bm_total_weight(mdev) - mdev->rs_failed;
/* >> 10 to prevent overflow,
* +1 to prevent division by zero */
if (*bits_left > mdev->rs_total) {
/* doh. maybe a logic bug somewhere.
* may also be just a race condition
* between this and a disconnect during sync.
* for now, just prevent in-kernel buffer overflow.
*/
smp_rmb();
dev_warn(DEV, "cs:%s rs_left=%lu > rs_total=%lu (rs_failed %lu)\n",
drbd_conn_str(mdev->state.conn),
*bits_left, mdev->rs_total, mdev->rs_failed);
*per_mil_done = 0;
} else {
/* make sure the calculation happens in long context */
unsigned long tmp = 1000UL -
(*bits_left >> 10)*1000UL
/ ((mdev->rs_total >> 10) + 1UL);
*per_mil_done = tmp;
}
}
/* this throttles on-the-fly application requests
* according to max_buffers settings;
* maybe re-implement using semaphores? */
static inline int drbd_get_max_buffers(struct drbd_conf *mdev)
{
int mxb = 1000000; /* arbitrary limit on open requests */
if (get_net_conf(mdev)) {
mxb = mdev->net_conf->max_buffers;
put_net_conf(mdev);
}
return mxb;
}
static inline int drbd_state_is_stable(union drbd_state s)
{
/* DO NOT add a default clause, we want the compiler to warn us
* for any newly introduced state we may have forgotten to add here */
switch ((enum drbd_conns)s.conn) {
/* new io only accepted when there is no connection, ... */
case C_STANDALONE:
case C_WF_CONNECTION:
/* ... or there is a well established connection. */
case C_CONNECTED:
case C_SYNC_SOURCE:
case C_SYNC_TARGET:
case C_VERIFY_S:
case C_VERIFY_T:
case C_PAUSED_SYNC_S:
case C_PAUSED_SYNC_T:
/* maybe stable, look at the disk state */
break;
/* no new io accepted during tansitional states
* like handshake or teardown */
case C_DISCONNECTING:
case C_UNCONNECTED:
case C_TIMEOUT:
case C_BROKEN_PIPE:
case C_NETWORK_FAILURE:
case C_PROTOCOL_ERROR:
case C_TEAR_DOWN:
case C_WF_REPORT_PARAMS:
case C_STARTING_SYNC_S:
case C_STARTING_SYNC_T:
case C_WF_BITMAP_S:
case C_WF_BITMAP_T:
case C_WF_SYNC_UUID:
case C_MASK:
/* not "stable" */
return 0;
}
switch ((enum drbd_disk_state)s.disk) {
case D_DISKLESS:
case D_INCONSISTENT:
case D_OUTDATED:
case D_CONSISTENT:
case D_UP_TO_DATE:
/* disk state is stable as well. */
break;
/* no new io accepted during tansitional states */
case D_ATTACHING:
case D_FAILED:
case D_NEGOTIATING:
case D_UNKNOWN:
case D_MASK:
/* not "stable" */
return 0;
}
return 1;
}
static inline int __inc_ap_bio_cond(struct drbd_conf *mdev)
{
int mxb = drbd_get_max_buffers(mdev);
if (mdev->state.susp)
return 0;
if (test_bit(SUSPEND_IO, &mdev->flags))
return 0;
/* to avoid potential deadlock or bitmap corruption,
* in various places, we only allow new application io
* to start during "stable" states. */
/* no new io accepted when attaching or detaching the disk */
if (!drbd_state_is_stable(mdev->state))
return 0;
/* since some older kernels don't have atomic_add_unless,
* and we are within the spinlock anyways, we have this workaround. */
if (atomic_read(&mdev->ap_bio_cnt) > mxb)
return 0;
if (test_bit(BITMAP_IO, &mdev->flags))
return 0;
return 1;
}
/* I'd like to use wait_event_lock_irq,
* but I'm not sure when it got introduced,
* and not sure when it has 3 or 4 arguments */
static inline void inc_ap_bio(struct drbd_conf *mdev, int count)
{
/* compare with after_state_ch,
* os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S */
DEFINE_WAIT(wait);
/* we wait here
* as long as the device is suspended
* until the bitmap is no longer on the fly during connection
* handshake as long as we would exeed the max_buffer limit.
*
* to avoid races with the reconnect code,
* we need to atomic_inc within the spinlock. */
spin_lock_irq(&mdev->req_lock);
while (!__inc_ap_bio_cond(mdev)) {
prepare_to_wait(&mdev->misc_wait, &wait, TASK_UNINTERRUPTIBLE);
spin_unlock_irq(&mdev->req_lock);
schedule();
finish_wait(&mdev->misc_wait, &wait);
spin_lock_irq(&mdev->req_lock);
}
atomic_add(count, &mdev->ap_bio_cnt);
spin_unlock_irq(&mdev->req_lock);
}
static inline void dec_ap_bio(struct drbd_conf *mdev)
{
int mxb = drbd_get_max_buffers(mdev);
int ap_bio = atomic_dec_return(&mdev->ap_bio_cnt);
D_ASSERT(ap_bio >= 0);
/* this currently does wake_up for every dec_ap_bio!
* maybe rather introduce some type of hysteresis?
* e.g. (ap_bio == mxb/2 || ap_bio == 0) ? */
if (ap_bio < mxb)
wake_up(&mdev->misc_wait);
if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
}
}
static inline void drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val)
{
mdev->ed_uuid = val;
}
static inline int seq_cmp(u32 a, u32 b)
{
/* we assume wrap around at 32bit.
* for wrap around at 24bit (old atomic_t),
* we'd have to
* a <<= 8; b <<= 8;
*/
return (s32)(a) - (s32)(b);
}
#define seq_lt(a, b) (seq_cmp((a), (b)) < 0)
#define seq_gt(a, b) (seq_cmp((a), (b)) > 0)
#define seq_ge(a, b) (seq_cmp((a), (b)) >= 0)
#define seq_le(a, b) (seq_cmp((a), (b)) <= 0)
/* CAUTION: please no side effects in arguments! */
#define seq_max(a, b) ((u32)(seq_gt((a), (b)) ? (a) : (b)))
static inline void update_peer_seq(struct drbd_conf *mdev, unsigned int new_seq)
{
unsigned int m;
spin_lock(&mdev->peer_seq_lock);
m = seq_max(mdev->peer_seq, new_seq);
mdev->peer_seq = m;
spin_unlock(&mdev->peer_seq_lock);
if (m == new_seq)
wake_up(&mdev->seq_wait);
}
static inline void drbd_update_congested(struct drbd_conf *mdev)
{
struct sock *sk = mdev->data.socket->sk;
if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
set_bit(NET_CONGESTED, &mdev->flags);
}
static inline int drbd_queue_order_type(struct drbd_conf *mdev)
{
/* sorry, we currently have no working implementation
* of distributed TCQ stuff */
#ifndef QUEUE_ORDERED_NONE
#define QUEUE_ORDERED_NONE 0
#endif
return QUEUE_ORDERED_NONE;
}
static inline void drbd_blk_run_queue(struct request_queue *q)
{
if (q && q->unplug_fn)
q->unplug_fn(q);
}
static inline void drbd_kick_lo(struct drbd_conf *mdev)
{
if (get_ldev(mdev)) {
drbd_blk_run_queue(bdev_get_queue(mdev->ldev->backing_bdev));
put_ldev(mdev);
}
}
static inline void drbd_md_flush(struct drbd_conf *mdev)
{
int r;
if (test_bit(MD_NO_BARRIER, &mdev->flags))
return;
r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_KERNEL, NULL,
BLKDEV_IFL_WAIT);
if (r) {
set_bit(MD_NO_BARRIER, &mdev->flags);
dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);
}
}
#endif
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