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kernel-ark/drivers/block/drbd/drbd_int.h
Philipp Reisner 57737adc96 drbd: Fix adding of new minors with freshly created meta data 
Online adding of new minors with freshly created meta data
to an resource with an established connection failed, with a
wrong state transition on one side on one side of the new minor.

Freshly created meta-data has a la_size (last agreed size) of 0.
When we online add such devices, the code wrongly got into
the code path for resyncing new storage that was added while
the disk was detached.

Fixed that by making the GREW from ZERO a special case.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2013-11-08 09:10:28 -07:00

2352 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/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 <linux/idr.h>
#include <net/tcp.h>
#include <linux/lru_cache.h>
#include <linux/prefetch.h>
#include <linux/drbd_genl_api.h>
#include <linux/drbd.h>
#include "drbd_state.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 bool disable_sendpage;
extern bool allow_oos;
#ifdef CONFIG_DRBD_FAULT_INJECTION
extern int enable_faults;
extern int fault_rate;
extern int fault_devs;
#endif
extern char usermode_helper[];
/* 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
#define ID_IN_SYNC (4711ULL)
#define ID_OUT_OF_SYNC (4712ULL)
#define ID_SYNCER (-1ULL)
#define UUID_NEW_BM_OFFSET ((u64)0x0001000000000000ULL)
struct drbd_conf;
struct drbd_tconn;
/* to shorten dev_warn(DEV, "msg"); and relatives statements */
#define DEV (disk_to_dev(mdev->vdisk))
#define conn_printk(LEVEL, TCONN, FMT, ARGS...) \
printk(LEVEL "d-con %s: " FMT, TCONN->name , ## ARGS)
#define conn_alert(TCONN, FMT, ARGS...) conn_printk(KERN_ALERT, TCONN, FMT, ## ARGS)
#define conn_crit(TCONN, FMT, ARGS...) conn_printk(KERN_CRIT, TCONN, FMT, ## ARGS)
#define conn_err(TCONN, FMT, ARGS...) conn_printk(KERN_ERR, TCONN, FMT, ## ARGS)
#define conn_warn(TCONN, FMT, ARGS...) conn_printk(KERN_WARNING, TCONN, FMT, ## ARGS)
#define conn_notice(TCONN, FMT, ARGS...) conn_printk(KERN_NOTICE, TCONN, FMT, ## ARGS)
#define conn_info(TCONN, FMT, ARGS...) conn_printk(KERN_INFO, TCONN, FMT, ## ARGS)
#define conn_dbg(TCONN, FMT, ARGS...) conn_printk(KERN_DEBUG, TCONN, FMT, ## ARGS)
#define D_ASSERT(exp) if (!(exp)) \
dev_err(DEV, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__)
/**
* expect - Make an assertion
*
* Unlike the assert macro, this macro returns a boolean result.
*/
#define expect(exp) ({ \
bool _bool = (exp); \
if (!_bool) \
dev_err(DEV, "ASSERTION %s FAILED in %s\n", \
#exp, __func__); \
_bool; \
})
/* 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,
};
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) {
#ifdef CONFIG_DRBD_FAULT_INJECTION
return fault_rate &&
(enable_faults & (1<<type)) &&
_drbd_insert_fault(mdev, type);
#else
return 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))
extern struct ratelimit_state drbd_ratelimit_state;
extern struct idr minors; /* RCU, updates: genl_lock() */
extern struct list_head drbd_tconns; /* RCU, updates: genl_lock() */
/* on the wire */
enum drbd_packet {
/* 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_SUPERSEDED = 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_OUT_OF_SYNC = 0x28, /* Mark as out of sync (Outrunning), data socket */
P_RS_CANCEL = 0x29, /* meta: Used to cancel RS_DATA_REQUEST packet by SyncSource */
P_CONN_ST_CHG_REQ = 0x2a, /* data sock: Connection wide state request */
P_CONN_ST_CHG_REPLY = 0x2b, /* meta sock: Connection side state req reply */
P_RETRY_WRITE = 0x2c, /* Protocol C: retry conflicting write request */
P_PROTOCOL_UPDATE = 0x2d, /* data sock: is used in established connections */
P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
P_MAX_OPT_CMD = 0x101,
/* special command ids for handshake */
P_INITIAL_META = 0xfff1, /* First Packet on the MetaSock */
P_INITIAL_DATA = 0xfff2, /* First Packet on the Socket */
P_CONNECTION_FEATURES = 0xfffe /* FIXED for the next century! */
};
extern const char *cmdname(enum drbd_packet 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_header80 {
u32 magic;
u16 command;
u16 length; /* bytes of data after this header */
} __packed;
/* Header for big packets, Used for data packets exceeding 64kB */
struct p_header95 {
u16 magic; /* use DRBD_MAGIC_BIG here */
u16 command;
u32 length;
} __packed;
struct p_header100 {
u32 magic;
u16 volume;
u16 command;
u32 length;
u32 pad;
} __packed;
extern unsigned int drbd_header_size(struct drbd_tconn *tconn);
/* these defines must not be changed without changing the protocol version */
#define DP_HARDBARRIER 1 /* depricated */
#define DP_RW_SYNC 2 /* equals REQ_SYNC */
#define DP_MAY_SET_IN_SYNC 4
#define DP_UNPLUG 8 /* not used anymore */
#define DP_FUA 16 /* equals REQ_FUA */
#define DP_FLUSH 32 /* equals REQ_FLUSH */
#define DP_DISCARD 64 /* equals REQ_DISCARD */
#define DP_SEND_RECEIVE_ACK 128 /* This is a proto B write request */
#define DP_SEND_WRITE_ACK 256 /* This is a proto C write request */
struct p_data {
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_SUPERSEDED (proto C, two-primaries conflict detection)
* p_block_req:
* P_DATA_REQUEST, P_RS_DATA_REQUEST
*/
struct p_block_ack {
u64 sector;
u64 block_id;
u32 blksize;
u32 seq_num;
} __packed;
struct p_block_req {
u64 sector;
u64 block_id;
u32 blksize;
u32 pad; /* to multiple of 8 Byte */
} __packed;
/*
* commands with their own struct for additional fields:
* P_CONNECTION_FEATURES
* P_BARRIER
* P_BARRIER_ACK
* P_SYNC_PARAM
* ReportParams
*/
struct p_connection_features {
u32 protocol_min;
u32 feature_flags;
u32 protocol_max;
/* should be more than enough for future enhancements
* for now, feature_flags and the reserved array shall be zero.
*/
u32 _pad;
u64 reserved[7];
} __packed;
struct p_barrier {
u32 barrier; /* barrier number _handle_ only */
u32 pad; /* to multiple of 8 Byte */
} __packed;
struct p_barrier_ack {
u32 barrier;
u32 set_size;
} __packed;
struct p_rs_param {
u32 resync_rate;
/* Since protocol version 88 and higher. */
char verify_alg[0];
} __packed;
struct p_rs_param_89 {
u32 resync_rate;
/* protocol version 89: */
char verify_alg[SHARED_SECRET_MAX];
char csums_alg[SHARED_SECRET_MAX];
} __packed;
struct p_rs_param_95 {
u32 resync_rate;
char verify_alg[SHARED_SECRET_MAX];
char csums_alg[SHARED_SECRET_MAX];
u32 c_plan_ahead;
u32 c_delay_target;
u32 c_fill_target;
u32 c_max_rate;
} __packed;
enum drbd_conn_flags {
CF_DISCARD_MY_DATA = 1,
CF_DRY_RUN = 2,
};
struct p_protocol {
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 {
u64 uuid[UI_EXTENDED_SIZE];
} __packed;
struct p_rs_uuid {
u64 uuid;
} __packed;
struct p_sizes {
u64 d_size; /* size of disk */
u64 u_size; /* user requested size */
u64 c_size; /* current exported size */
u32 max_bio_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 {
u32 state;
} __packed;
struct p_req_state {
u32 mask;
u32 val;
} __packed;
struct p_req_state_reply {
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_block_desc {
u64 sector;
u32 blksize;
u32 pad; /* to multiple of 8 Byte */
} __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 {
/* (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_probe93 {
u32 seq_num; /* sequence number to match the two probe packets */
u32 offset; /* usecs the probe got sent after the reference time point */
} __packed;
/*
* Bitmap packets need to fit within a single page on the sender and receiver,
* so we are limited to 4 KiB (and not to PAGE_SIZE, which can be bigger).
*/
#define DRBD_SOCKET_BUFFER_SIZE 4096
/**********************************************************************/
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_tconn *tconn;
int reset_cpu_mask;
char name[9];
};
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;
}
struct drbd_work {
struct list_head list;
int (*cb)(struct drbd_work *, int cancel);
union {
struct drbd_conf *mdev;
struct drbd_tconn *tconn;
};
};
#include "drbd_interval.h"
extern int drbd_wait_misc(struct drbd_conf *, struct drbd_interval *);
struct drbd_request {
struct drbd_work w;
/* 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_request_endio(). */
struct bio *private_bio;
struct drbd_interval i;
/* epoch: used to check on "completion" whether this req was in
* the current epoch, and we therefore have to close it,
* causing a p_barrier packet to be send, starting a new epoch.
*
* This corresponds to "barrier" in struct p_barrier[_ack],
* and to "barrier_nr" in struct drbd_epoch (and various
* comments/function parameters/local variable names).
*/
unsigned int epoch;
struct list_head tl_requests; /* ring list in the transfer log */
struct bio *master_bio; /* master bio pointer */
unsigned long start_time;
/* once it hits 0, we may complete the master_bio */
atomic_t completion_ref;
/* once it hits 0, we may destroy this drbd_request object */
struct kref kref;
unsigned rq_state; /* see comments above _req_mod() */
};
struct drbd_epoch {
struct drbd_tconn *tconn;
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_HAVE_BARRIER_NUMBER,
};
enum epoch_event {
EV_PUT,
EV_GOT_BARRIER_NR,
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_peer_request {
struct drbd_work w;
struct drbd_epoch *epoch; /* for writes */
struct page *pages;
atomic_t pending_bios;
struct drbd_interval i;
/* see comments on ee flag bits below */
unsigned long flags;
union {
u64 block_id;
struct digest_info *digest;
};
};
/* 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,
/* In case a barrier failed,
* we need to resubmit without the barrier flag. */
__EE_RESUBMITTED,
/* we may have several bios per peer request.
* if any of those fail, we set this flag atomically
* from the endio callback */
__EE_WAS_ERROR,
/* This ee has a pointer to a digest instead of a block id */
__EE_HAS_DIGEST,
/* Conflicting local requests need to be restarted after this request */
__EE_RESTART_REQUESTS,
/* The peer wants a write ACK for this (wire proto C) */
__EE_SEND_WRITE_ACK,
/* Is set when net_conf had two_primaries set while creating this peer_req */
__EE_IN_INTERVAL_TREE,
};
#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_RESUBMITTED (1<<__EE_RESUBMITTED)
#define EE_WAS_ERROR (1<<__EE_WAS_ERROR)
#define EE_HAS_DIGEST (1<<__EE_HAS_DIGEST)
#define EE_RESTART_REQUESTS (1<<__EE_RESTART_REQUESTS)
#define EE_SEND_WRITE_ACK (1<<__EE_SEND_WRITE_ACK)
#define EE_IN_INTERVAL_TREE (1<<__EE_IN_INTERVAL_TREE)
/* flag bits per mdev */
enum {
UNPLUG_REMOTE, /* sending a "UnplugRemote" could help */
MD_DIRTY, /* current uuids and flags not yet on disk */
USE_DEGR_WFC_T, /* degr-wfc-timeout instead of wfc-timeout. */
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. */
CONSIDER_RESYNC,
MD_NO_FUA, /* Users wants us to not use FUA/FLUSH on meta data dev */
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 */
GO_DISKLESS, /* Disk is being detached, on io-error or admin request. */
WAS_IO_ERROR, /* Local disk failed, returned IO error */
WAS_READ_ERROR, /* Local disk READ failed (set additionally to the above) */
FORCE_DETACH, /* Force-detach from local disk, aborting any pending local IO */
RESYNC_AFTER_NEG, /* Resync after online grow after the attach&negotiate finished. */
RESIZE_PENDING, /* Size change detected locally, waiting for the response from
* the peer, if it changed there as well. */
NEW_CUR_UUID, /* Create new current UUID when thawing IO */
AL_SUSPENDED, /* Activity logging is currently suspended. */
AHEAD_TO_SYNC_SOURCE, /* Ahead -> SyncSource queued */
B_RS_H_DONE, /* Before resync handler done (already executed) */
DISCARD_MY_DATA, /* discard_my_data flag per volume */
READ_BALANCE_RR,
};
struct drbd_bitmap; /* opaque for drbd_conf */
/* definition of bits in bm_flags to be used in drbd_bm_lock
* and drbd_bitmap_io and friends. */
enum bm_flag {
/* do we need to kfree, or vfree bm_pages? */
BM_P_VMALLOCED = 0x10000, /* internal use only, will be masked out */
/* currently locked for bulk operation */
BM_LOCKED_MASK = 0xf,
/* in detail, that is: */
BM_DONT_CLEAR = 0x1,
BM_DONT_SET = 0x2,
BM_DONT_TEST = 0x4,
/* so we can mark it locked for bulk operation,
* and still allow all non-bulk operations */
BM_IS_LOCKED = 0x8,
/* (test bit, count bit) allowed (common case) */
BM_LOCKED_TEST_ALLOWED = BM_DONT_CLEAR | BM_DONT_SET | BM_IS_LOCKED,
/* testing bits, as well as setting new bits allowed, but clearing bits
* would be unexpected. Used during bitmap receive. Setting new bits
* requires sending of "out-of-sync" information, though. */
BM_LOCKED_SET_ALLOWED = BM_DONT_CLEAR | BM_IS_LOCKED,
/* for drbd_bm_write_copy_pages, everything is allowed,
* only concurrent bulk operations are locked out. */
BM_LOCKED_CHANGE_ALLOWED = BM_IS_LOCKED,
};
struct drbd_work_queue {
struct list_head q;
spinlock_t q_lock; /* to protect the list. */
wait_queue_head_t q_wait;
};
struct drbd_socket {
struct mutex mutex;
struct socket *socket;
/* this way we get our
* send/receive buffers off the stack */
void *sbuf;
void *rbuf;
};
struct drbd_md {
u64 md_offset; /* sector offset to 'super' block */
u64 la_size_sect; /* last agreed size, unit sectors */
spinlock_t uuid_lock;
u64 uuid[UI_SIZE];
u64 device_uuid;
u32 flags;
u32 md_size_sect;
s32 al_offset; /* signed relative sector offset to activity log */
s32 bm_offset; /* signed relative sector offset to bitmap */
/* cached value of bdev->disk_conf->meta_dev_idx (see below) */
s32 meta_dev_idx;
/* see al_tr_number_to_on_disk_sector() */
u32 al_stripes;
u32 al_stripe_size_4k;
u32 al_size_4k; /* cached product of the above */
};
struct drbd_backing_dev {
struct block_device *backing_bdev;
struct block_device *md_bdev;
struct drbd_md md;
struct disk_conf *disk_conf; /* RCU, for updates: mdev->tconn->conf_update */
sector_t known_size; /* last known size of that backing device */
};
struct drbd_md_io {
unsigned int done;
int error;
};
struct bm_io_work {
struct drbd_work w;
char *why;
enum bm_flag flags;
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,
};
struct fifo_buffer {
unsigned int head_index;
unsigned int size;
int total; /* sum of all values */
int values[0];
};
extern struct fifo_buffer *fifo_alloc(int fifo_size);
/* flag bits per tconn */
enum {
NET_CONGESTED, /* The data socket is congested */
RESOLVE_CONFLICTS, /* Set on one node, cleared on the peer! */
SEND_PING, /* whether asender should send a ping asap */
SIGNAL_ASENDER, /* whether asender wants to be interrupted */
GOT_PING_ACK, /* set when we receive a ping_ack packet, ping_wait gets woken */
CONN_WD_ST_CHG_REQ, /* A cluster wide state change on the connection is active */
CONN_WD_ST_CHG_OKAY,
CONN_WD_ST_CHG_FAIL,
CONN_DRY_RUN, /* Expect disconnect after resync handshake. */
CREATE_BARRIER, /* next P_DATA is preceded by a P_BARRIER */
STATE_SENT, /* Do not change state/UUIDs while this is set */
CALLBACK_PENDING, /* Whether we have a call_usermodehelper(, UMH_WAIT_PROC)
* pending, from drbd worker context.
* If set, bdi_write_congested() returns true,
* so shrink_page_list() would not recurse into,
* and potentially deadlock on, this drbd worker.
*/
DISCONNECT_SENT,
};
struct drbd_tconn { /* is a resource from the config file */
char *name; /* Resource name */
struct list_head all_tconn; /* linked on global drbd_tconns */
struct kref kref;
struct idr volumes; /* <tconn, vnr> to mdev mapping */
enum drbd_conns cstate; /* Only C_STANDALONE to C_WF_REPORT_PARAMS */
unsigned susp:1; /* IO suspended by user */
unsigned susp_nod:1; /* IO suspended because no data */
unsigned susp_fen:1; /* IO suspended because fence peer handler runs */
struct mutex cstate_mutex; /* Protects graceful disconnects */
unsigned int connect_cnt; /* Inc each time a connection is established */
unsigned long flags;
struct net_conf *net_conf; /* content protected by rcu */
struct mutex conf_update; /* mutex for ready-copy-update of net_conf and disk_conf */
wait_queue_head_t ping_wait; /* Woken upon reception of a ping, and a state change */
struct res_opts res_opts;
struct sockaddr_storage my_addr;
int my_addr_len;
struct sockaddr_storage peer_addr;
int peer_addr_len;
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;
spinlock_t req_lock;
struct list_head transfer_log; /* all requests not yet fully processed */
struct crypto_hash *cram_hmac_tfm;
struct crypto_hash *integrity_tfm; /* checksums we compute, updates protected by tconn->data->mutex */
struct crypto_hash *peer_integrity_tfm; /* checksums we verify, only accessed from receiver thread */
struct crypto_hash *csums_tfm;
struct crypto_hash *verify_tfm;
void *int_dig_in;
void *int_dig_vv;
/* receiver side */
struct drbd_epoch *current_epoch;
spinlock_t epoch_lock;
unsigned int epochs;
enum write_ordering_e write_ordering;
atomic_t current_tle_nr; /* transfer log epoch number */
unsigned current_tle_writes; /* writes seen within this tl epoch */
unsigned long last_reconnect_jif;
struct drbd_thread receiver;
struct drbd_thread worker;
struct drbd_thread asender;
cpumask_var_t cpu_mask;
/* sender side */
struct drbd_work_queue sender_work;
struct {
/* whether this sender thread
* has processed a single write yet. */
bool seen_any_write_yet;
/* Which barrier number to send with the next P_BARRIER */
int current_epoch_nr;
/* how many write requests have been sent
* with req->epoch == current_epoch_nr.
* If none, no P_BARRIER will be sent. */
unsigned current_epoch_writes;
} send;
};
struct submit_worker {
struct workqueue_struct *wq;
struct work_struct worker;
spinlock_t lock;
struct list_head writes;
};
struct drbd_conf {
struct drbd_tconn *tconn;
int vnr; /* volume number within the connection */
struct kref kref;
/* things that are stored as / read from meta data on disk */
unsigned long flags;
/* configured by drbdsetup */
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;
unsigned long last_reattach_jif;
struct drbd_work resync_work,
unplug_work,
go_diskless,
md_sync_work,
start_resync_work;
struct timer_list resync_timer;
struct timer_list md_sync_timer;
struct timer_list start_resync_timer;
struct timer_list request_timer;
#ifdef DRBD_DEBUG_MD_SYNC
struct {
unsigned int line;
const char* func;
} last_md_mark_dirty;
#endif
/* Used after attach while negotiating new disk state. */
union drbd_state new_state_tmp;
union drbd_dev_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 replies for */
atomic_t local_cnt; /* Waiting for local completion */
/* Interval tree of pending local requests */
struct rb_root read_requests;
struct rb_root write_requests;
/* blocks to resync in this run [unit BM_BLOCK_SIZE] */
unsigned long rs_total;
/* number of resync blocks 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;
/* skipped because csum was equal [unit BM_BLOCK_SIZE] */
unsigned long rs_same_csum;
#define DRBD_SYNC_MARKS 8
#define DRBD_SYNC_MARK_STEP (3*HZ)
/* block not up-to-date at mark [unit BM_BLOCK_SIZE] */
unsigned long rs_mark_left[DRBD_SYNC_MARKS];
/* marks's time [unit jiffies] */
unsigned long rs_mark_time[DRBD_SYNC_MARKS];
/* current index into rs_mark_{left,time} */
int rs_last_mark;
unsigned long rs_last_bcast; /* [unit jiffies] */
/* where does the admin want us to start? (sector) */
sector_t ov_start_sector;
sector_t ov_stop_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 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 list_head active_ee; /* IO in progress (P_DATA gets written to disk) */
struct list_head sync_ee; /* IO in progress (P_RS_DATA_REPLY gets written to disk) */
struct list_head done_ee; /* need to send P_WRITE_ACK */
struct list_head read_ee; /* [RS]P_DATA_REQUEST being read */
struct list_head net_ee; /* zero-copy network send in progress */
int next_barrier_nr;
struct list_head resync_reads;
atomic_t pp_in_use; /* allocated from page pool */
atomic_t pp_in_use_by_net; /* sendpage()d, still referenced by tcp */
wait_queue_head_t ee_wait;
struct page *md_io_page; /* one page buffer for md_io */
struct drbd_md_io md_io;
atomic_t md_io_in_use; /* protects the md_io, md_io_page and md_io_tmpp */
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;
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. */
struct bm_io_work bm_io_work;
u64 ed_uuid; /* UUID of the exposed data */
struct mutex own_state_mutex;
struct mutex *state_mutex; /* either own_state_mutex or mdev->tconn->cstate_mutex */
char congestion_reason; /* Why we where congested... */
atomic_t rs_sect_in; /* for incoming resync data rate, SyncTarget */
atomic_t rs_sect_ev; /* for submitted resync data rate, both */
int rs_last_sect_ev; /* counter to compare with */
int rs_last_events; /* counter of read or write "events" (unit sectors)
* on the lower level device when we last looked. */
int c_sync_rate; /* current resync rate after syncer throttle magic */
struct fifo_buffer *rs_plan_s; /* correction values of resync planer (RCU, tconn->conn_update) */
int rs_in_flight; /* resync sectors in flight (to proxy, in proxy and from proxy) */
atomic_t ap_in_flight; /* App sectors in flight (waiting for ack) */
unsigned int peer_max_bio_size;
unsigned int local_max_bio_size;
/* any requests that would block in drbd_make_request()
* are deferred to this single-threaded work queue */
struct submit_worker submit;
};
static inline struct drbd_conf *minor_to_mdev(unsigned int minor)
{
return (struct drbd_conf *)idr_find(&minors, minor);
}
static inline unsigned int mdev_to_minor(struct drbd_conf *mdev)
{
return mdev->minor;
}
static inline struct drbd_conf *vnr_to_mdev(struct drbd_tconn *tconn, int vnr)
{
return (struct drbd_conf *)idr_find(&tconn->volumes, vnr);
}
/*
* function declarations
*************************/
/* drbd_main.c */
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_thread_start(struct drbd_thread *thi);
extern void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait);
extern char *drbd_task_to_thread_name(struct drbd_tconn *tconn, struct task_struct *task);
#ifdef CONFIG_SMP
extern void drbd_thread_current_set_cpu(struct drbd_thread *thi);
extern void drbd_calc_cpu_mask(struct drbd_tconn *tconn);
#else
#define drbd_thread_current_set_cpu(A) ({})
#define drbd_calc_cpu_mask(A) ({})
#endif
extern void tl_release(struct drbd_tconn *, unsigned int barrier_nr,
unsigned int set_size);
extern void tl_clear(struct drbd_tconn *);
extern void drbd_free_sock(struct drbd_tconn *tconn);
extern int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
void *buf, size_t size, unsigned msg_flags);
extern int drbd_send_all(struct drbd_tconn *, struct socket *, void *, size_t,
unsigned);
extern int __drbd_send_protocol(struct drbd_tconn *tconn, enum drbd_packet cmd);
extern int drbd_send_protocol(struct drbd_tconn *tconn);
extern int drbd_send_uuids(struct drbd_conf *mdev);
extern int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev);
extern void drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev);
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, union drbd_state s);
extern int drbd_send_current_state(struct drbd_conf *mdev);
extern int drbd_send_sync_param(struct drbd_conf *mdev);
extern void drbd_send_b_ack(struct drbd_tconn *tconn, u32 barrier_nr,
u32 set_size);
extern int drbd_send_ack(struct drbd_conf *, enum drbd_packet,
struct drbd_peer_request *);
extern void drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packet cmd,
struct p_block_req *rp);
extern void drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packet cmd,
struct p_data *dp, int data_size);
extern int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packet cmd,
sector_t sector, int blksize, u64 block_id);
extern int drbd_send_out_of_sync(struct drbd_conf *, struct drbd_request *);
extern int drbd_send_block(struct drbd_conf *, enum drbd_packet,
struct drbd_peer_request *);
extern int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req);
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_packet 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 void drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode);
extern void conn_send_sr_reply(struct drbd_tconn *tconn, enum drbd_state_rv retcode);
extern void drbd_free_bc(struct drbd_backing_dev *ldev);
extern void drbd_mdev_cleanup(struct drbd_conf *mdev);
void drbd_print_uuids(struct drbd_conf *mdev, const char *text);
extern void conn_md_sync(struct drbd_tconn *tconn);
extern void drbd_md_write(struct drbd_conf *mdev, void *buffer);
extern void drbd_md_sync(struct drbd_conf *mdev);
extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev);
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_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local);
extern void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local);
extern void __drbd_uuid_set(struct drbd_conf *mdev, int idx, 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);
#ifndef DRBD_DEBUG_MD_SYNC
extern void drbd_md_mark_dirty(struct drbd_conf *mdev);
#else
#define drbd_md_mark_dirty(m) drbd_md_mark_dirty_(m, __LINE__ , __func__ )
extern void drbd_md_mark_dirty_(struct drbd_conf *mdev,
unsigned int line, const char *func);
#endif
extern void drbd_queue_bitmap_io(struct drbd_conf *mdev,
int (*io_fn)(struct drbd_conf *),
void (*done)(struct drbd_conf *, int),
char *why, enum bm_flag flags);
extern int drbd_bitmap_io(struct drbd_conf *mdev,
int (*io_fn)(struct drbd_conf *),
char *why, enum bm_flag flags);
extern int drbd_bitmap_io_from_worker(struct drbd_conf *mdev,
int (*io_fn)(struct drbd_conf *),
char *why, enum bm_flag flags);
extern int drbd_bmio_set_n_write(struct drbd_conf *mdev);
extern int drbd_bmio_clear_n_write(struct drbd_conf *mdev);
extern void drbd_ldev_destroy(struct drbd_conf *mdev);
/* Meta data layout
*
* We currently have two possible layouts.
* Offsets in (512 byte) sectors.
* external:
* |----------- md_size_sect ------------------|
* [ 4k superblock ][ activity log ][ Bitmap ]
* | al_offset == 8 |
* | bm_offset = al_offset + X |
* ==> bitmap sectors = md_size_sect - bm_offset
*
* Variants:
* old, indexed fixed size meta data:
*
* internal:
* |----------- md_size_sect ------------------|
* [data.....][ Bitmap ][ activity log ][ 4k superblock ][padding*]
* | al_offset < 0 |
* | bm_offset = al_offset - Y |
* ==> bitmap sectors = Y = al_offset - bm_offset
*
* [padding*] are zero or up to 7 unused 512 Byte sectors to the
* end of the device, so that the [4k superblock] will be 4k aligned.
*
* The activity log consists of 4k transaction blocks,
* which are written in a ring-buffer, or striped ring-buffer like fashion,
* which are writtensize used to be fixed 32kB,
* but is about to become configurable.
*/
/* Our old fixed size meta data layout
* allows up to about 3.8TB, so if you want more,
* you need to use the "flexible" meta data format. */
#define MD_128MB_SECT (128LLU << 11) /* 128 MB, unit sectors */
#define MD_4kB_SECT 8
#define MD_32kB_SECT 64
/* One activity log extent represents 4M of storage */
#define AL_EXTENT_SHIFT 22
#define AL_EXTENT_SIZE (1<<AL_EXTENT_SHIFT)
/* We could make these currently hardcoded constants configurable
* variables at create-md time (or even re-configurable at runtime?).
* Which will require some more changes to the DRBD "super block"
* and attach code.
*
* updates per transaction:
* This many changes to the active set can be logged with one transaction.
* This number is arbitrary.
* context per transaction:
* This many context extent numbers are logged with each transaction.
* This number is resulting from the transaction block size (4k), the layout
* of the transaction header, and the number of updates per transaction.
* See drbd_actlog.c:struct al_transaction_on_disk
* */
#define AL_UPDATES_PER_TRANSACTION 64 // arbitrary
#define AL_CONTEXT_PER_TRANSACTION 919 // (4096 - 36 - 6*64)/4
#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. */
#define BME_PRIORITY 2 /* finish resync IO on this extent ASAP! App IO waiting! */
/* 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 SLEEP_TIME (HZ/10)
/* We do bitmap IO in units of 4k blocks.
* We also still have a hardcoded 4k per bit relation. */
#define BM_BLOCK_SHIFT 12 /* 4k per bit */
#define BM_BLOCK_SIZE (1<<BM_BLOCK_SHIFT)
/* mostly arbitrarily set the represented size of one bitmap extent,
* aka resync extent, to 16 MiB (which is also 512 Byte worth of bitmap
* at 4k per bit resolution) */
#define BM_EXT_SHIFT 24 /* 16 MiB per resync extent */
#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_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)
/* we have a certain meta data variant that has a fixed on-disk size of 128
* MiB, of which 4k are our "superblock", and 32k are the fixed size activity
* log, leaving this many sectors for the bitmap.
*/
#define DRBD_MAX_SECTORS_FIXED_BM \
((MD_128MB_SECT - MD_32kB_SECT - MD_4kB_SECT) * (1LL<<(BM_EXT_SHIFT-9)))
#if !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_FIXED_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
/* we allow up to 1 PiB now on 64bit architecture with "flexible" meta data */
#define DRBD_MAX_SECTORS_FLEX (1UL << 51)
/* corresponds to (1UL << 38) bits right now. */
#endif
#endif
/* BIO_MAX_SIZE is 256 * PAGE_CACHE_SIZE,
* so for typical PAGE_CACHE_SIZE of 4k, that is (1<<20) Byte.
* Since we may live in a mixed-platform cluster,
* we limit us to a platform agnostic constant here for now.
* A followup commit may allow even bigger BIO sizes,
* once we thought that through. */
#define DRBD_MAX_BIO_SIZE (1U << 20)
#if DRBD_MAX_BIO_SIZE > BIO_MAX_SIZE
#error Architecture not supported: DRBD_MAX_BIO_SIZE > BIO_MAX_SIZE
#endif
#define DRBD_MAX_BIO_SIZE_SAFE (1U << 12) /* Works always = 4k */
#define DRBD_MAX_SIZE_H80_PACKET (1U << 15) /* Header 80 only allows packets up to 32KiB data */
#define DRBD_MAX_BIO_SIZE_P95 (1U << 17) /* Protocol 95 to 99 allows bios up to 128KiB */
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);
/* set/clear/test only a few bits at a time */
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);
extern int drbd_bm_count_bits(
struct drbd_conf *mdev, const unsigned long s, const unsigned long e);
/* bm_set_bits variant for use while holding drbd_bm_lock,
* may process the whole bitmap in one go */
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_page(struct drbd_conf *mdev, unsigned int idx) __must_hold(local);
extern int drbd_bm_read(struct drbd_conf *mdev) __must_hold(local);
extern void drbd_bm_mark_for_writeout(struct drbd_conf *mdev, int page_nr);
extern int drbd_bm_write(struct drbd_conf *mdev) __must_hold(local);
extern int drbd_bm_write_hinted(struct drbd_conf *mdev) __must_hold(local);
extern int drbd_bm_write_all(struct drbd_conf *mdev) __must_hold(local);
extern int drbd_bm_write_copy_pages(struct drbd_conf *mdev) __must_hold(local);
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);
#define DRBD_END_OF_BITMAP (~(unsigned long)0)
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 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 */
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, enum bm_flag flags);
extern void drbd_bm_unlock(struct drbd_conf *mdev);
/* drbd_main.c */
extern struct kmem_cache *drbd_request_cache;
extern struct kmem_cache *drbd_ee_cache; /* peer requests */
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;
/* drbd's page pool, used to buffer data received from the peer,
* or data requested by the peer.
*
* This does not have an emergency reserve.
*
* When allocating from this pool, it first takes pages from the pool.
* Only if the pool is depleted will try to allocate from the system.
*
* The assumption is that pages taken from this pool will be processed,
* and given back, "quickly", and then can be recycled, so we can avoid
* frequent calls to alloc_page(), and still will be able to make progress even
* under memory pressure.
*/
extern struct page *drbd_pp_pool;
extern spinlock_t drbd_pp_lock;
extern int drbd_pp_vacant;
extern wait_queue_head_t drbd_pp_wait;
/* We also need a standard (emergency-reserve backed) page pool
* for meta data IO (activity log, bitmap).
* We can keep it global, as long as it is used as "N pages at a time".
* 128 should be plenty, currently we probably can get away with as few as 1.
*/
#define DRBD_MIN_POOL_PAGES 128
extern mempool_t *drbd_md_io_page_pool;
/* We also need to make sure we get a bio
* when we need it for housekeeping purposes */
extern struct bio_set *drbd_md_io_bio_set;
/* to allocate from that set */
extern struct bio *bio_alloc_drbd(gfp_t gfp_mask);
extern rwlock_t global_state_lock;
extern int conn_lowest_minor(struct drbd_tconn *tconn);
enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr);
extern void drbd_minor_destroy(struct kref *kref);
extern int set_resource_options(struct drbd_tconn *tconn, struct res_opts *res_opts);
extern struct drbd_tconn *conn_create(const char *name, struct res_opts *res_opts);
extern void conn_destroy(struct kref *kref);
struct drbd_tconn *conn_get_by_name(const char *name);
extern struct drbd_tconn *conn_get_by_addrs(void *my_addr, int my_addr_len,
void *peer_addr, int peer_addr_len);
extern void conn_free_crypto(struct drbd_tconn *tconn);
extern int proc_details;
/* drbd_req */
extern void do_submit(struct work_struct *ws);
extern void __drbd_make_request(struct drbd_conf *, struct bio *, unsigned long);
extern void drbd_make_request(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 int drbd_msg_put_info(const char *info);
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 *, sector_t, int);
enum determine_dev_size {
DS_ERROR_SHRINK = -3,
DS_ERROR_SPACE_MD = -2,
DS_ERROR = -1,
DS_UNCHANGED = 0,
DS_SHRUNK = 1,
DS_GREW = 2,
DS_GREW_FROM_ZERO = 3,
};
extern enum determine_dev_size
drbd_determine_dev_size(struct drbd_conf *, enum dds_flags, struct resize_parms *) __must_hold(local);
extern void resync_after_online_grow(struct drbd_conf *);
extern void drbd_reconsider_max_bio_size(struct drbd_conf *mdev);
extern enum drbd_state_rv drbd_set_role(struct drbd_conf *mdev,
enum drbd_role new_role,
int force);
extern bool conn_try_outdate_peer(struct drbd_tconn *tconn);
extern void conn_try_outdate_peer_async(struct drbd_tconn *tconn);
extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
/* drbd_worker.c */
extern int drbd_worker(struct drbd_thread *thi);
enum drbd_ret_code drbd_resync_after_valid(struct drbd_conf *mdev, int o_minor);
void drbd_resync_after_changed(struct drbd_conf *mdev);
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 void *drbd_md_get_buffer(struct drbd_conf *mdev);
extern void drbd_md_put_buffer(struct drbd_conf *mdev);
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_out_of_sync_found(struct drbd_conf *, sector_t, int);
extern void wait_until_done_or_force_detached(struct drbd_conf *mdev,
struct drbd_backing_dev *bdev, unsigned int *done);
extern void drbd_rs_controller_reset(struct drbd_conf *mdev);
static inline void ov_out_of_sync_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_peer_request *, void *);
/* worker callbacks */
extern int w_e_end_data_req(struct drbd_work *, int);
extern int w_e_end_rsdata_req(struct drbd_work *, int);
extern int w_e_end_csum_rs_req(struct drbd_work *, int);
extern int w_e_end_ov_reply(struct drbd_work *, int);
extern int w_e_end_ov_req(struct drbd_work *, int);
extern int w_ov_finished(struct drbd_work *, int);
extern int w_resync_timer(struct drbd_work *, int);
extern int w_send_write_hint(struct drbd_work *, int);
extern int w_make_resync_request(struct drbd_work *, int);
extern int w_send_dblock(struct drbd_work *, int);
extern int w_send_read_req(struct drbd_work *, int);
extern int w_prev_work_done(struct drbd_work *, int);
extern int w_e_reissue(struct drbd_work *, int);
extern int w_restart_disk_io(struct drbd_work *, int);
extern int w_send_out_of_sync(struct drbd_work *, int);
extern int w_start_resync(struct drbd_work *, int);
extern void resync_timer_fn(unsigned long data);
extern void start_resync_timer_fn(unsigned long data);
/* drbd_receiver.c */
extern int drbd_rs_should_slow_down(struct drbd_conf *mdev, sector_t sector);
extern int drbd_submit_peer_request(struct drbd_conf *,
struct drbd_peer_request *, const unsigned,
const int);
extern int drbd_free_peer_reqs(struct drbd_conf *, struct list_head *);
extern struct drbd_peer_request *drbd_alloc_peer_req(struct drbd_conf *, u64,
sector_t, unsigned int,
gfp_t) __must_hold(local);
extern void __drbd_free_peer_req(struct drbd_conf *, struct drbd_peer_request *,
int);
#define drbd_free_peer_req(m,e) __drbd_free_peer_req(m, e, 0)
#define drbd_free_net_peer_req(m,e) __drbd_free_peer_req(m, e, 1)
extern struct page *drbd_alloc_pages(struct drbd_conf *, unsigned int, bool);
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 conn_flush_workqueue(struct drbd_tconn *tconn);
extern int drbd_connected(struct drbd_conf *mdev);
static inline void drbd_flush_workqueue(struct drbd_conf *mdev)
{
conn_flush_workqueue(mdev->tconn);
}
/* Yes, there is kernel_setsockopt, but only since 2.6.18.
* So we have our own copy of it here. */
static inline int drbd_setsockopt(struct socket *sock, int level, int optname,
char *optval, int optlen)
{
mm_segment_t oldfs = get_fs();
char __user *uoptval;
int err;
uoptval = (char __user __force *)optval;
set_fs(KERNEL_DS);
if (level == SOL_SOCKET)
err = sock_setsockopt(sock, level, optname, uoptval, optlen);
else
err = sock->ops->setsockopt(sock, level, optname, uoptval,
optlen);
set_fs(oldfs);
return err;
}
static inline void drbd_tcp_cork(struct socket *sock)
{
int val = 1;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
(char*)&val, sizeof(val));
}
static inline void drbd_tcp_uncork(struct socket *sock)
{
int val = 0;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_CORK,
(char*)&val, sizeof(val));
}
static inline void drbd_tcp_nodelay(struct socket *sock)
{
int val = 1;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_NODELAY,
(char*)&val, sizeof(val));
}
static inline void drbd_tcp_quickack(struct socket *sock)
{
int val = 2;
(void) drbd_setsockopt(sock, SOL_TCP, TCP_QUICKACK,
(char*)&val, sizeof(val));
}
void drbd_bump_write_ordering(struct drbd_tconn *tconn, 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 int drbd_al_begin_io_nonblock(struct drbd_conf *mdev, struct drbd_interval *i);
extern void drbd_al_begin_io_commit(struct drbd_conf *mdev, bool delegate);
extern bool drbd_al_begin_io_fastpath(struct drbd_conf *mdev, struct drbd_interval *i);
extern void drbd_al_begin_io(struct drbd_conf *mdev, struct drbd_interval *i, bool delegate);
extern void drbd_al_complete_io(struct drbd_conf *mdev, struct drbd_interval *i);
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 void drbd_advance_rs_marks(struct drbd_conf *mdev, unsigned long still_to_go);
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 int __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_shrink(struct drbd_conf *mdev);
extern int drbd_initialize_al(struct drbd_conf *, void *);
/* drbd_nl.c */
/* state info broadcast */
struct sib_info {
enum drbd_state_info_bcast_reason sib_reason;
union {
struct {
char *helper_name;
unsigned helper_exit_code;
};
struct {
union drbd_state os;
union drbd_state ns;
};
};
};
void drbd_bcast_event(struct drbd_conf *mdev, const struct sib_info *sib);
/*
* 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_peer_req_has_active_page(struct drbd_peer_request *peer_req)
{
struct page *page = peer_req->pages;
page_chain_for_each(page) {
if (page_count(page) > 1)
return 1;
}
return 0;
}
static inline enum drbd_state_rv
_drbd_set_state(struct drbd_conf *mdev, union drbd_state ns,
enum chg_state_flags flags, struct completion *done)
{
enum drbd_state_rv rv;
read_lock(&global_state_lock);
rv = __drbd_set_state(mdev, ns, flags, done);
read_unlock(&global_state_lock);
return rv;
}
static inline union drbd_state drbd_read_state(struct drbd_conf *mdev)
{
union drbd_state rv;
rv.i = mdev->state.i;
rv.susp = mdev->tconn->susp;
rv.susp_nod = mdev->tconn->susp_nod;
rv.susp_fen = mdev->tconn->susp_fen;
return rv;
}
enum drbd_force_detach_flags {
DRBD_READ_ERROR,
DRBD_WRITE_ERROR,
DRBD_META_IO_ERROR,
DRBD_FORCE_DETACH,
};
#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,
enum drbd_force_detach_flags df,
const char *where)
{
enum drbd_io_error_p ep;
rcu_read_lock();
ep = rcu_dereference(mdev->ldev->disk_conf)->on_io_error;
rcu_read_unlock();
switch (ep) {
case EP_PASS_ON: /* FIXME would this be better named "Ignore"? */
if (df == DRBD_READ_ERROR || df == DRBD_WRITE_ERROR) {
if (__ratelimit(&drbd_ratelimit_state))
dev_err(DEV, "Local IO failed in %s.\n", where);
if (mdev->state.disk > D_INCONSISTENT)
_drbd_set_state(_NS(mdev, disk, D_INCONSISTENT), CS_HARD, NULL);
break;
}
/* NOTE fall through for DRBD_META_IO_ERROR or DRBD_FORCE_DETACH */
case EP_DETACH:
case EP_CALL_HELPER:
/* Remember whether we saw a READ or WRITE error.
*
* Recovery of the affected area for WRITE failure is covered
* by the activity log.
* READ errors may fall outside that area though. Certain READ
* errors can be "healed" by writing good data to the affected
* blocks, which triggers block re-allocation in lower layers.
*
* If we can not write the bitmap after a READ error,
* we may need to trigger a full sync (see w_go_diskless()).
*
* Force-detach is not really an IO error, but rather a
* desperate measure to try to deal with a completely
* unresponsive lower level IO stack.
* Still it should be treated as a WRITE error.
*
* Meta IO error is always WRITE error:
* we read meta data only once during attach,
* which will fail in case of errors.
*/
set_bit(WAS_IO_ERROR, &mdev->flags);
if (df == DRBD_READ_ERROR)
set_bit(WAS_READ_ERROR, &mdev->flags);
if (df == DRBD_FORCE_DETACH)
set_bit(FORCE_DETACH, &mdev->flags);
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, enum drbd_force_detach_flags forcedetach, const char *where)
{
if (error) {
unsigned long flags;
spin_lock_irqsave(&mdev->tconn->req_lock, flags);
__drbd_chk_io_error_(mdev, forcedetach, where);
spin_unlock_irqrestore(&mdev->tconn->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->md.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->md.meta_dev_idx) {
case DRBD_MD_INDEX_INTERNAL:
case DRBD_MD_INDEX_FLEX_INT:
return bdev->md.md_offset + MD_4kB_SECT -1;
case DRBD_MD_INDEX_FLEX_EXT:
default:
return bdev->md.md_offset + bdev->md.md_size_sect -1;
}
}
/* 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 ? i_size_read(bdev->bd_inode) >> 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->md.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
* @bdev: Meta data block device.
*/
static inline sector_t drbd_md_ss(struct drbd_backing_dev *bdev)
{
const int meta_dev_idx = bdev->md.meta_dev_idx;
if (meta_dev_idx == DRBD_MD_INDEX_FLEX_EXT)
return 0;
/* Since drbd08, internal meta data is always "flexible".
* position: last 4k aligned block of 4k size */
if (meta_dev_idx == DRBD_MD_INDEX_INTERNAL ||
meta_dev_idx == DRBD_MD_INDEX_FLEX_INT)
return (drbd_get_capacity(bdev->backing_bdev) & ~7ULL) - 8;
/* external, some index; this is the old fixed size layout */
return MD_128MB_SECT * bdev->md.meta_dev_idx;
}
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);
spin_unlock_irqrestore(&q->q_lock, flags);
wake_up(&q->q_wait);
}
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);
spin_unlock_irqrestore(&q->q_lock, flags);
wake_up(&q->q_wait);
}
static inline void wake_asender(struct drbd_tconn *tconn)
{
if (test_bit(SIGNAL_ASENDER, &tconn->flags))
force_sig(DRBD_SIG, tconn->asender.task);
}
static inline void request_ping(struct drbd_tconn *tconn)
{
set_bit(SEND_PING, &tconn->flags);
wake_asender(tconn);
}
extern void *conn_prepare_command(struct drbd_tconn *, struct drbd_socket *);
extern void *drbd_prepare_command(struct drbd_conf *, struct drbd_socket *);
extern int conn_send_command(struct drbd_tconn *, struct drbd_socket *,
enum drbd_packet, unsigned int, void *,
unsigned int);
extern int drbd_send_command(struct drbd_conf *, struct drbd_socket *,
enum drbd_packet, unsigned int, void *,
unsigned int);
extern int drbd_send_ping(struct drbd_tconn *tconn);
extern int drbd_send_ping_ack(struct drbd_tconn *tconn);
extern int drbd_send_state_req(struct drbd_conf *, union drbd_state, union drbd_state);
extern int conn_send_state_req(struct drbd_tconn *, union drbd_state, union drbd_state);
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, func, line) \
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) _dec_ap_pending(mdev, __FUNCTION__, __LINE__)
static inline void _dec_ap_pending(struct drbd_conf *mdev, const char *func, int line)
{
if (atomic_dec_and_test(&mdev->ap_pending_cnt))
wake_up(&mdev->misc_wait);
ERR_IF_CNT_IS_NEGATIVE(ap_pending_cnt, func, line);
}
/* 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 with 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) _dec_rs_pending(mdev, __FUNCTION__, __LINE__)
static inline void _dec_rs_pending(struct drbd_conf *mdev, const char *func, int line)
{
atomic_dec(&mdev->rs_pending_cnt);
ERR_IF_CNT_IS_NEGATIVE(rs_pending_cnt, func, line);
}
/* 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) _dec_unacked(mdev, __FUNCTION__, __LINE__)
static inline void _dec_unacked(struct drbd_conf *mdev, const char *func, int line)
{
atomic_dec(&mdev->unacked_cnt);
ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line);
}
#define sub_unacked(mdev, n) _sub_unacked(mdev, n, __FUNCTION__, __LINE__)
static inline void _sub_unacked(struct drbd_conf *mdev, int n, const char *func, int line)
{
atomic_sub(n, &mdev->unacked_cnt);
ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line);
}
/**
* 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)
{
int i = atomic_dec_return(&mdev->local_cnt);
/* This may be called from some endio handler,
* so we must not sleep here. */
__release(local);
D_ASSERT(i >= 0);
if (i == 0) {
if (mdev->state.disk == D_DISKLESS)
/* even internal references gone, safe to destroy */
drbd_ldev_destroy(mdev);
if (mdev->state.disk == D_FAILED) {
/* all application IO references gone. */
if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
drbd_queue_work(&mdev->tconn->sender_work, &mdev->go_diskless);
}
wake_up(&mdev->misc_wait);
}
}
#ifndef __CHECKER__
static inline int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
{
int io_allowed;
/* never get a reference while D_DISKLESS */
if (mdev->state.disk == D_DISKLESS)
return 0;
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, in case we
* want to support more than (1<<32) bits on a 32bit arch. */
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. */
if (mdev->state.conn == C_VERIFY_S || mdev->state.conn == C_VERIFY_T)
*bits_left = mdev->ov_left;
else
*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 division happens in long context.
* We allow up to one petabyte storage right now,
* at a granularity of 4k per bit that is 2**38 bits.
* After shift right and multiplication by 1000,
* this should still fit easily into a 32bit long,
* so we don't need a 64bit division on 32bit arch.
* Note: currently we don't support such large bitmaps on 32bit
* arch anyways, but no harm done to be prepared for it here.
*/
unsigned int shift = mdev->rs_total > UINT_MAX ? 16 : 10;
unsigned long left = *bits_left >> shift;
unsigned long total = 1UL + (mdev->rs_total >> shift);
unsigned long tmp = 1000UL - left * 1000UL/total;
*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)
{
struct net_conf *nc;
int mxb;
rcu_read_lock();
nc = rcu_dereference(mdev->tconn->net_conf);
mxb = nc ? nc->max_buffers : 1000000; /* arbitrary limit on open requests */
rcu_read_unlock();
return mxb;
}
static inline int drbd_state_is_stable(struct drbd_conf *mdev)
{
union drbd_dev_state s = mdev->state;
/* 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:
case C_AHEAD:
case C_BEHIND:
/* transitional states, IO allowed */
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:
break;
/* Allow IO in BM exchange states with new protocols */
case C_WF_BITMAP_S:
if (mdev->tconn->agreed_pro_version < 96)
return 0;
break;
/* no new io accepted in these states */
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:
case D_FAILED:
/* disk state is stable as well. */
break;
/* no new io accepted during transitional states */
case D_ATTACHING:
case D_NEGOTIATING:
case D_UNKNOWN:
case D_MASK:
/* not "stable" */
return 0;
}
return 1;
}
static inline int drbd_suspended(struct drbd_conf *mdev)
{
struct drbd_tconn *tconn = mdev->tconn;
return tconn->susp || tconn->susp_fen || tconn->susp_nod;
}
static inline bool may_inc_ap_bio(struct drbd_conf *mdev)
{
int mxb = drbd_get_max_buffers(mdev);
if (drbd_suspended(mdev))
return false;
if (test_bit(SUSPEND_IO, &mdev->flags))
return false;
/* 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))
return false;
/* 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 false;
if (test_bit(BITMAP_IO, &mdev->flags))
return false;
return true;
}
static inline bool inc_ap_bio_cond(struct drbd_conf *mdev)
{
bool rv = false;
spin_lock_irq(&mdev->tconn->req_lock);
rv = may_inc_ap_bio(mdev);
if (rv)
atomic_inc(&mdev->ap_bio_cnt);
spin_unlock_irq(&mdev->tconn->req_lock);
return rv;
}
static inline void inc_ap_bio(struct drbd_conf *mdev)
{
/* 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 exceed the max_buffer limit.
*
* to avoid races with the reconnect code,
* we need to atomic_inc within the spinlock. */
wait_event(mdev->misc_wait, inc_ap_bio_cond(mdev));
}
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);
if (ap_bio == 0 && test_bit(BITMAP_IO, &mdev->flags)) {
if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
drbd_queue_work(&mdev->tconn->sender_work, &mdev->bm_io_work.w);
}
/* 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);
}
static inline bool verify_can_do_stop_sector(struct drbd_conf *mdev)
{
return mdev->tconn->agreed_pro_version >= 97 &&
mdev->tconn->agreed_pro_version != 100;
}
static inline int drbd_set_ed_uuid(struct drbd_conf *mdev, u64 val)
{
int changed = mdev->ed_uuid != val;
mdev->ed_uuid = val;
return changed;
}
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_md_flush(struct drbd_conf *mdev)
{
int r;
if (mdev->ldev == NULL) {
dev_warn(DEV, "mdev->ldev == NULL in drbd_md_flush\n");
return;
}
if (test_bit(MD_NO_FUA, &mdev->flags))
return;
r = blkdev_issue_flush(mdev->ldev->md_bdev, GFP_NOIO, NULL);
if (r) {
set_bit(MD_NO_FUA, &mdev->flags);
dev_err(DEV, "meta data flush failed with status %d, disabling md-flushes\n", r);
}
}
#endif
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