| /* |
| 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/backing-dev.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_strings.h" |
| #include "drbd_state.h" |
| #include "drbd_protocol.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 |
| |
| /* module parameter, defined in drbd_main.c */ |
| extern unsigned int minor_count; |
| extern bool disable_sendpage; |
| extern bool allow_oos; |
| void tl_abort_disk_io(struct drbd_device *device); |
| |
| #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_device; |
| struct drbd_connection; |
| |
| #define __drbd_printk_device(level, device, fmt, args...) \ |
| dev_printk(level, disk_to_dev((device)->vdisk), fmt, ## args) |
| #define __drbd_printk_peer_device(level, peer_device, fmt, args...) \ |
| dev_printk(level, disk_to_dev((peer_device)->device->vdisk), fmt, ## args) |
| #define __drbd_printk_resource(level, resource, fmt, args...) \ |
| printk(level "drbd %s: " fmt, (resource)->name, ## args) |
| #define __drbd_printk_connection(level, connection, fmt, args...) \ |
| printk(level "drbd %s: " fmt, (connection)->resource->name, ## args) |
| |
| void drbd_printk_with_wrong_object_type(void); |
| |
| #define __drbd_printk_if_same_type(obj, type, func, level, fmt, args...) \ |
| (__builtin_types_compatible_p(typeof(obj), type) || \ |
| __builtin_types_compatible_p(typeof(obj), const type)), \ |
| func(level, (const type)(obj), fmt, ## args) |
| |
| #define drbd_printk(level, obj, fmt, args...) \ |
| __builtin_choose_expr( \ |
| __drbd_printk_if_same_type(obj, struct drbd_device *, \ |
| __drbd_printk_device, level, fmt, ## args), \ |
| __builtin_choose_expr( \ |
| __drbd_printk_if_same_type(obj, struct drbd_resource *, \ |
| __drbd_printk_resource, level, fmt, ## args), \ |
| __builtin_choose_expr( \ |
| __drbd_printk_if_same_type(obj, struct drbd_connection *, \ |
| __drbd_printk_connection, level, fmt, ## args), \ |
| __builtin_choose_expr( \ |
| __drbd_printk_if_same_type(obj, struct drbd_peer_device *, \ |
| __drbd_printk_peer_device, level, fmt, ## args), \ |
| drbd_printk_with_wrong_object_type())))) |
| |
| #define drbd_dbg(obj, fmt, args...) \ |
| drbd_printk(KERN_DEBUG, obj, fmt, ## args) |
| #define drbd_alert(obj, fmt, args...) \ |
| drbd_printk(KERN_ALERT, obj, fmt, ## args) |
| #define drbd_err(obj, fmt, args...) \ |
| drbd_printk(KERN_ERR, obj, fmt, ## args) |
| #define drbd_warn(obj, fmt, args...) \ |
| drbd_printk(KERN_WARNING, obj, fmt, ## args) |
| #define drbd_info(obj, fmt, args...) \ |
| drbd_printk(KERN_INFO, obj, fmt, ## args) |
| #define drbd_emerg(obj, fmt, args...) \ |
| drbd_printk(KERN_EMERG, obj, fmt, ## args) |
| |
| #define dynamic_drbd_dbg(device, fmt, args...) \ |
| dynamic_dev_dbg(disk_to_dev(device->vdisk), fmt, ## args) |
| |
| #define D_ASSERT(device, exp) do { \ |
| if (!(exp)) \ |
| drbd_err(device, "ASSERT( " #exp " ) in %s:%d\n", __FILE__, __LINE__); \ |
| } while (0) |
| |
| /** |
| * expect - Make an assertion |
| * |
| * Unlike the assert macro, this macro returns a boolean result. |
| */ |
| #define expect(exp) ({ \ |
| bool _bool = (exp); \ |
| if (!_bool) \ |
| drbd_err(device, "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_device *device, unsigned int type); |
| |
| static inline int |
| drbd_insert_fault(struct drbd_device *device, unsigned int type) { |
| #ifdef CONFIG_DRBD_FAULT_INJECTION |
| return fault_rate && |
| (enable_faults & (1<<type)) && |
| _drbd_insert_fault(device, 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 drbd_devices; /* RCU, updates: genl_lock() */ |
| extern struct list_head drbd_resources; /* RCU, updates: genl_lock() */ |
| |
| 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_device *device, |
| 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 |
| } |
| |
| extern unsigned int drbd_header_size(struct drbd_connection *connection); |
| |
| /**********************************************************************/ |
| 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_resource *resource; |
| struct drbd_connection *connection; |
| int reset_cpu_mask; |
| const char *name; |
| }; |
| |
| 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); |
| }; |
| |
| struct drbd_device_work { |
| struct drbd_work w; |
| struct drbd_device *device; |
| }; |
| |
| #include "drbd_interval.h" |
| |
| extern int drbd_wait_misc(struct drbd_device *, struct drbd_interval *); |
| |
| struct drbd_request { |
| struct drbd_work w; |
| struct drbd_device *device; |
| |
| /* 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 */ |
| |
| /* see struct drbd_device */ |
| struct list_head req_pending_master_completion; |
| struct list_head req_pending_local; |
| |
| /* for generic IO accounting */ |
| unsigned long start_jif; |
| |
| /* for DRBD internal statistics */ |
| |
| /* Minimal set of time stamps to determine if we wait for activity log |
| * transactions, local disk or peer. 32 bit "jiffies" are good enough, |
| * we don't expect a DRBD request to be stalled for several month. |
| */ |
| |
| /* before actual request processing */ |
| unsigned long in_actlog_jif; |
| |
| /* local disk */ |
| unsigned long pre_submit_jif; |
| |
| /* per connection */ |
| unsigned long pre_send_jif; |
| unsigned long acked_jif; |
| unsigned long net_done_jif; |
| |
| /* Possibly even more detail to track each phase: |
| * master_completion_jif |
| * how long did it take to complete the master bio |
| * (application visible latency) |
| * allocated_jif |
| * how long the master bio was blocked until we finally allocated |
| * a tracking struct |
| * in_actlog_jif |
| * how long did we wait for activity log transactions |
| * |
| * net_queued_jif |
| * when did we finally queue it for sending |
| * pre_send_jif |
| * when did we start sending it |
| * post_send_jif |
| * how long did we block in the network stack trying to send it |
| * acked_jif |
| * when did we receive (or fake, in protocol A) a remote ACK |
| * net_done_jif |
| * when did we receive final acknowledgement (P_BARRIER_ACK), |
| * or decide, e.g. on connection loss, that we do no longer expect |
| * anything from this peer for this request. |
| * |
| * pre_submit_jif |
| * post_sub_jif |
| * when did we start submiting to the lower level device, |
| * and how long did we block in that submit function |
| * local_completion_jif |
| * how long did it take the lower level device to complete this request |
| */ |
| |
| |
| /* 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_connection *connection; |
| 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; |
| }; |
| |
| /* Prototype declaration of function defined in drbd_receiver.c */ |
| int drbdd_init(struct drbd_thread *); |
| int drbd_asender(struct drbd_thread *); |
| |
| /* 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 digest_info { |
| int digest_size; |
| void *digest; |
| }; |
| |
| struct drbd_peer_request { |
| struct drbd_work w; |
| struct drbd_peer_device *peer_device; |
| 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; |
| unsigned long submit_jif; |
| 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, |
| |
| /* is this a TRIM aka REQ_DISCARD? */ |
| __EE_IS_TRIM, |
| /* our lower level cannot handle trim, |
| * and we want to fall back to zeroout instead */ |
| __EE_IS_TRIM_USE_ZEROOUT, |
| |
| /* 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, |
| |
| /* for debugfs: */ |
| /* has this been submitted, or does it still wait for something else? */ |
| __EE_SUBMITTED, |
| |
| /* this is/was a write request */ |
| __EE_WRITE, |
| |
| /* this originates from application on peer |
| * (not some resync or verify or other DRBD internal request) */ |
| __EE_APPLICATION, |
| }; |
| #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_TRIM (1<<__EE_IS_TRIM) |
| #define EE_IS_TRIM_USE_ZEROOUT (1<<__EE_IS_TRIM_USE_ZEROOUT) |
| #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) |
| #define EE_SUBMITTED (1<<__EE_SUBMITTED) |
| #define EE_WRITE (1<<__EE_WRITE) |
| #define EE_APPLICATION (1<<__EE_APPLICATION) |
| |
| /* flag bits per device */ |
| 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 */ |
| 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, |
| |
| FLUSH_PENDING, /* if set, device->flush_jif is when we submitted that flush |
| * from drbd_flush_after_epoch() */ |
| |
| /* cleared only after backing device related structures have been destroyed. */ |
| GOING_DISKLESS, /* Disk is being detached, because of io-error, or admin request. */ |
| |
| /* to be used in drbd_device_post_work() */ |
| GO_DISKLESS, /* tell worker to schedule cleanup before detach */ |
| DESTROY_DISK, /* tell worker to close backing devices and destroy related structures. */ |
| MD_SYNC, /* tell worker to call drbd_md_sync() */ |
| RS_START, /* tell worker to start resync/OV */ |
| RS_PROGRESS, /* tell worker that resync made significant progress */ |
| RS_DONE, /* tell worker that resync is done */ |
| }; |
| |
| struct drbd_bitmap; /* opaque for drbd_device */ |
| |
| /* 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: resource->conf_update */ |
| sector_t known_size; /* last known size of that backing device */ |
| }; |
| |
| struct drbd_md_io { |
| struct page *page; |
| unsigned long start_jif; /* last call to drbd_md_get_buffer */ |
| unsigned long submit_jif; /* last _drbd_md_sync_page_io() submit */ |
| const char *current_use; |
| atomic_t in_use; |
| unsigned int done; |
| int error; |
| }; |
| |
| struct bm_io_work { |
| struct drbd_work w; |
| char *why; |
| enum bm_flag flags; |
| int (*io_fn)(struct drbd_device *device); |
| void (*done)(struct drbd_device *device, 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 connection */ |
| 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, |
| |
| DEVICE_WORK_PENDING, /* tell worker that some device has pending work */ |
| }; |
| |
| struct drbd_resource { |
| char *name; |
| #ifdef CONFIG_DEBUG_FS |
| struct dentry *debugfs_res; |
| struct dentry *debugfs_res_volumes; |
| struct dentry *debugfs_res_connections; |
| struct dentry *debugfs_res_in_flight_summary; |
| #endif |
| struct kref kref; |
| struct idr devices; /* volume number to device mapping */ |
| struct list_head connections; |
| struct list_head resources; |
| struct res_opts res_opts; |
| struct mutex conf_update; /* mutex for ready-copy-update of net_conf and disk_conf */ |
| struct mutex adm_mutex; /* mutex to serialize administrative requests */ |
| spinlock_t req_lock; |
| |
| 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 */ |
| |
| enum write_ordering_e write_ordering; |
| |
| cpumask_var_t cpu_mask; |
| }; |
| |
| struct drbd_thread_timing_details |
| { |
| unsigned long start_jif; |
| void *cb_addr; |
| const char *caller_fn; |
| unsigned int line; |
| unsigned int cb_nr; |
| }; |
| |
| struct drbd_connection { |
| struct list_head connections; |
| struct drbd_resource *resource; |
| #ifdef CONFIG_DEBUG_FS |
| struct dentry *debugfs_conn; |
| struct dentry *debugfs_conn_callback_history; |
| struct dentry *debugfs_conn_oldest_requests; |
| #endif |
| struct kref kref; |
| struct idr peer_devices; /* volume number to peer device mapping */ |
| enum drbd_conns cstate; /* Only C_STANDALONE to C_WF_REPORT_PARAMS */ |
| 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 */ |
| wait_queue_head_t ping_wait; /* Woken upon reception of a ping, and a state change */ |
| |
| 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 */ |
| u32 agreed_features; |
| unsigned long last_received; /* in jiffies, either socket */ |
| unsigned int ko_count; |
| |
| 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 connection->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; |
| 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; |
| |
| /* cached pointers, |
| * so we can look up the oldest pending requests more quickly. |
| * protected by resource->req_lock */ |
| struct drbd_request *req_next; /* DRBD 9: todo.req_next */ |
| struct drbd_request *req_ack_pending; |
| struct drbd_request *req_not_net_done; |
| |
| /* sender side */ |
| struct drbd_work_queue sender_work; |
| |
| #define DRBD_THREAD_DETAILS_HIST 16 |
| unsigned int w_cb_nr; /* keeps counting up */ |
| unsigned int r_cb_nr; /* keeps counting up */ |
| struct drbd_thread_timing_details w_timing_details[DRBD_THREAD_DETAILS_HIST]; |
| struct drbd_thread_timing_details r_timing_details[DRBD_THREAD_DETAILS_HIST]; |
| |
| 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; |
| }; |
| |
| void __update_timing_details( |
| struct drbd_thread_timing_details *tdp, |
| unsigned int *cb_nr, |
| void *cb, |
| const char *fn, const unsigned int line); |
| |
| #define update_worker_timing_details(c, cb) \ |
| __update_timing_details(c->w_timing_details, &c->w_cb_nr, cb, __func__ , __LINE__ ) |
| #define update_receiver_timing_details(c, cb) \ |
| __update_timing_details(c->r_timing_details, &c->r_cb_nr, cb, __func__ , __LINE__ ) |
| |
| struct submit_worker { |
| struct workqueue_struct *wq; |
| struct work_struct worker; |
| |
| /* protected by ..->resource->req_lock */ |
| struct list_head writes; |
| }; |
| |
| struct drbd_peer_device { |
| struct list_head peer_devices; |
| struct drbd_device *device; |
| struct drbd_connection *connection; |
| #ifdef CONFIG_DEBUG_FS |
| struct dentry *debugfs_peer_dev; |
| #endif |
| }; |
| |
| struct drbd_device { |
| struct drbd_resource *resource; |
| struct list_head peer_devices; |
| struct list_head pending_bitmap_io; |
| |
| unsigned long flush_jif; |
| #ifdef CONFIG_DEBUG_FS |
| struct dentry *debugfs_minor; |
| struct dentry *debugfs_vol; |
| struct dentry *debugfs_vol_oldest_requests; |
| struct dentry *debugfs_vol_act_log_extents; |
| struct dentry *debugfs_vol_resync_extents; |
| struct dentry *debugfs_vol_data_gen_id; |
| #endif |
| |
| unsigned int vnr; /* volume number within the connection */ |
| unsigned int minor; /* device minor number */ |
| |
| 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; |
| struct drbd_work unplug_work; |
| struct timer_list resync_timer; |
| struct timer_list md_sync_timer; |
| struct timer_list start_resync_timer; |
| struct timer_list request_timer; |
| |
| /* 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_actlog_cnt; /* Requests waiting for activity log */ |
| 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; |
| |
| /* for statistics and timeouts */ |
| /* [0] read, [1] write */ |
| struct list_head pending_master_completion[2]; |
| struct list_head pending_completion[2]; |
| |
| /* use checksums for *this* resync */ |
| bool use_csums; |
| /* 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 drbd_md_io md_io; |
| 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 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 first_peer_device(device)->connection->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, connection->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; |
| }; |
| |
| struct drbd_bm_aio_ctx { |
| struct drbd_device *device; |
| struct list_head list; /* on device->pending_bitmap_io */; |
| unsigned long start_jif; |
| atomic_t in_flight; |
| unsigned int done; |
| unsigned flags; |
| #define BM_AIO_COPY_PAGES 1 |
| #define BM_AIO_WRITE_HINTED 2 |
| #define BM_AIO_WRITE_ALL_PAGES 4 |
| #define BM_AIO_READ 8 |
| int error; |
| struct kref kref; |
| }; |
| |
| struct drbd_config_context { |
| /* assigned from drbd_genlmsghdr */ |
| unsigned int minor; |
| /* assigned from request attributes, if present */ |
| unsigned int volume; |
| #define VOLUME_UNSPECIFIED (-1U) |
| /* pointer into the request skb, |
| * limited lifetime! */ |
| char *resource_name; |
| struct nlattr *my_addr; |
| struct nlattr *peer_addr; |
| |
| /* reply buffer */ |
| struct sk_buff *reply_skb; |
| /* pointer into reply buffer */ |
| struct drbd_genlmsghdr *reply_dh; |
| /* resolved from attributes, if possible */ |
| struct drbd_device *device; |
| struct drbd_resource *resource; |
| struct drbd_connection *connection; |
| }; |
| |
| static inline struct drbd_device *minor_to_device(unsigned int minor) |
| { |
| return (struct drbd_device *)idr_find(&drbd_devices, minor); |
| } |
| |
| static inline struct drbd_peer_device *first_peer_device(struct drbd_device *device) |
| { |
| return list_first_entry_or_null(&device->peer_devices, struct drbd_peer_device, peer_devices); |
| } |
| |
| #define for_each_resource(resource, _resources) \ |
| list_for_each_entry(resource, _resources, resources) |
| |
| #define for_each_resource_rcu(resource, _resources) \ |
| list_for_each_entry_rcu(resource, _resources, resources) |
| |
| #define for_each_resource_safe(resource, tmp, _resources) \ |
| list_for_each_entry_safe(resource, tmp, _resources, resources) |
| |
| #define for_each_connection(connection, resource) \ |
| list_for_each_entry(connection, &resource->connections, connections) |
| |
| #define for_each_connection_rcu(connection, resource) \ |
| list_for_each_entry_rcu(connection, &resource->connections, connections) |
| |
| #define for_each_connection_safe(connection, tmp, resource) \ |
| list_for_each_entry_safe(connection, tmp, &resource->connections, connections) |
| |
| #define for_each_peer_device(peer_device, device) \ |
| list_for_each_entry(peer_device, &device->peer_devices, peer_devices) |
| |
| #define for_each_peer_device_rcu(peer_device, device) \ |
| list_for_each_entry_rcu(peer_device, &device->peer_devices, peer_devices) |
| |
| #define for_each_peer_device_safe(peer_device, tmp, device) \ |
| list_for_each_entry_safe(peer_device, tmp, &device->peer_devices, peer_devices) |
| |
| static inline unsigned int device_to_minor(struct drbd_device *device) |
| { |
| return device->minor; |
| } |
| |
| /* |
| * 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_device *device); |
| 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_thread *thi); |
| #else |
| #define drbd_thread_current_set_cpu(A) ({}) |
| #endif |
| extern void tl_release(struct drbd_connection *, unsigned int barrier_nr, |
| unsigned int set_size); |
| extern void tl_clear(struct drbd_connection *); |
| extern void drbd_free_sock(struct drbd_connection *connection); |
| extern int drbd_send(struct drbd_connection *connection, struct socket *sock, |
| void *buf, size_t size, unsigned msg_flags); |
| extern int drbd_send_all(struct drbd_connection *, struct socket *, void *, size_t, |
| unsigned); |
| |
| extern int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cmd); |
| extern int drbd_send_protocol(struct drbd_connection *connection); |
| extern int drbd_send_uuids(struct drbd_peer_device *); |
| extern int drbd_send_uuids_skip_initial_sync(struct drbd_peer_device *); |
| extern void drbd_gen_and_send_sync_uuid(struct drbd_peer_device *); |
| extern int drbd_send_sizes(struct drbd_peer_device *, int trigger_reply, enum dds_flags flags); |
| extern int drbd_send_state(struct drbd_peer_device *, union drbd_state s); |
| extern int drbd_send_current_state(struct drbd_peer_device *); |
| extern int drbd_send_sync_param(struct drbd_peer_device *); |
| extern void drbd_send_b_ack(struct drbd_connection *connection, u32 barrier_nr, |
| u32 set_size); |
| extern int drbd_send_ack(struct drbd_peer_device *, enum drbd_packet, |
| struct drbd_peer_request *); |
| extern void drbd_send_ack_rp(struct drbd_peer_device *, enum drbd_packet, |
| struct p_block_req *rp); |
| extern void drbd_send_ack_dp(struct drbd_peer_device *, enum drbd_packet, |
| struct p_data *dp, int data_size); |
| extern int drbd_send_ack_ex(struct drbd_peer_device *, enum drbd_packet, |
| sector_t sector, int blksize, u64 block_id); |
| extern int drbd_send_out_of_sync(struct drbd_peer_device *, struct drbd_request *); |
| extern int drbd_send_block(struct drbd_peer_device *, enum drbd_packet, |
| struct drbd_peer_request *); |
| extern int drbd_send_dblock(struct drbd_peer_device *, struct drbd_request *req); |
| extern int drbd_send_drequest(struct drbd_peer_device *, int cmd, |
| sector_t sector, int size, u64 block_id); |
| extern int drbd_send_drequest_csum(struct drbd_peer_device *, sector_t sector, |
| int size, void *digest, int digest_size, |
| enum drbd_packet cmd); |
| extern int drbd_send_ov_request(struct drbd_peer_device *, sector_t sector, int size); |
| |
| extern int drbd_send_bitmap(struct drbd_device *device); |
| extern void drbd_send_sr_reply(struct drbd_peer_device *, enum drbd_state_rv retcode); |
| extern void conn_send_sr_reply(struct drbd_connection *connection, enum drbd_state_rv retcode); |
| extern void drbd_free_ldev(struct drbd_backing_dev *ldev); |
| extern void drbd_device_cleanup(struct drbd_device *device); |
| void drbd_print_uuids(struct drbd_device *device, const char *text); |
| |
| extern void conn_md_sync(struct drbd_connection *connection); |
| extern void drbd_md_write(struct drbd_device *device, void *buffer); |
| extern void drbd_md_sync(struct drbd_device *device); |
| extern int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev); |
| extern void drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); |
| extern void _drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); |
| extern void drbd_uuid_new_current(struct drbd_device *device) __must_hold(local); |
| extern void drbd_uuid_set_bm(struct drbd_device *device, u64 val) __must_hold(local); |
| extern void drbd_uuid_move_history(struct drbd_device *device) __must_hold(local); |
| extern void __drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local); |
| extern void drbd_md_set_flag(struct drbd_device *device, int flags) __must_hold(local); |
| extern void drbd_md_clear_flag(struct drbd_device *device, int flags)__must_hold(local); |
| extern int drbd_md_test_flag(struct drbd_backing_dev *, int); |
| extern void drbd_md_mark_dirty(struct drbd_device *device); |
| extern void drbd_queue_bitmap_io(struct drbd_device *device, |
| int (*io_fn)(struct drbd_device *), |
| void (*done)(struct drbd_device *, int), |
| char *why, enum bm_flag flags); |
| extern int drbd_bitmap_io(struct drbd_device *device, |
| int (*io_fn)(struct drbd_device *), |
| char *why, enum bm_flag flags); |
| extern int drbd_bitmap_io_from_worker(struct drbd_device *device, |
| int (*io_fn)(struct drbd_device *), |
| char *why, enum bm_flag flags); |
| extern int drbd_bmio_set_n_write(struct drbd_device *device) __must_hold(local); |
| extern int drbd_bmio_clear_n_write(struct drbd_device *device) __must_hold(local); |
| |
| /* 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)) |
| #define BM_BIT_TO_EXT(x) ((x) >> (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) |
| |
| /* first storage sector a bitmap extent corresponds to */ |
| #define BM_EXT_TO_SECT(x) ((sector_t)(x) << (BM_EXT_SHIFT-9)) |
| /* how much _storage_ sectors we have per bitmap extent */ |
| #define BM_SECT_PER_EXT BM_EXT_TO_SECT(1) |
| /* how many bits are covered by one bitmap extent (resync extent) */ |
| #define BM_BITS_PER_EXT (1UL << (BM_EXT_SHIFT - BM_BLOCK_SHIFT)) |
| |
| #define BM_BLOCKS_PER_BM_EXT_MASK (BM_BITS_PER_EXT - 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)) |
| |
| /* 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 */ |
| |
| /* For now, don't allow more than one activity log extent worth of data |
| * to be discarded in one go. We may need to rework drbd_al_begin_io() |
| * to allow for even larger discard ranges */ |
| #define DRBD_MAX_DISCARD_SIZE AL_EXTENT_SIZE |
| #define DRBD_MAX_DISCARD_SECTORS (DRBD_MAX_DISCARD_SIZE >> 9) |
| |
| extern int drbd_bm_init(struct drbd_device *device); |
| extern int drbd_bm_resize(struct drbd_device *device, sector_t sectors, int set_new_bits); |
| extern void drbd_bm_cleanup(struct drbd_device *device); |
| extern void drbd_bm_set_all(struct drbd_device *device); |
| extern void drbd_bm_clear_all(struct drbd_device *device); |
| /* set/clear/test only a few bits at a time */ |
| extern int drbd_bm_set_bits( |
| struct drbd_device *device, unsigned long s, unsigned long e); |
| extern int drbd_bm_clear_bits( |
| struct drbd_device *device, unsigned long s, unsigned long e); |
| extern int drbd_bm_count_bits( |
| struct drbd_device *device, 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_device *device, |
| const unsigned long s, const unsigned long e); |
| extern int drbd_bm_test_bit(struct drbd_device *device, unsigned long bitnr); |
| extern int drbd_bm_e_weight(struct drbd_device *device, unsigned long enr); |
| extern int drbd_bm_read(struct drbd_device *device) __must_hold(local); |
| extern void drbd_bm_mark_for_writeout(struct drbd_device *device, int page_nr); |
| extern int drbd_bm_write(struct drbd_device *device) __must_hold(local); |
| extern int drbd_bm_write_hinted(struct drbd_device *device) __must_hold(local); |
| extern int drbd_bm_write_lazy(struct drbd_device *device, unsigned upper_idx) __must_hold(local); |
| extern int drbd_bm_write_all(struct drbd_device *device) __must_hold(local); |
| extern int drbd_bm_write_copy_pages(struct drbd_device *device) __must_hold(local); |
| extern size_t drbd_bm_words(struct drbd_device *device); |
| extern unsigned long drbd_bm_bits(struct drbd_device *device); |
| extern sector_t drbd_bm_capacity(struct drbd_device *device); |
| |
| #define DRBD_END_OF_BITMAP (~(unsigned long)0) |
| extern unsigned long drbd_bm_find_next(struct drbd_device *device, 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_device *device, unsigned long bm_fo); |
| extern unsigned long _drbd_bm_find_next_zero(struct drbd_device *device, unsigned long bm_fo); |
| extern unsigned long _drbd_bm_total_weight(struct drbd_device *device); |
| extern unsigned long drbd_bm_total_weight(struct drbd_device *device); |
| /* for receive_bitmap */ |
| extern void drbd_bm_merge_lel(struct drbd_device *device, size_t offset, |
| size_t number, unsigned long *buffer); |
| /* for _drbd_send_bitmap */ |
| extern void drbd_bm_get_lel(struct drbd_device *device, size_t offset, |
| size_t number, unsigned long *buffer); |
| |
| extern void drbd_bm_lock(struct drbd_device *device, char *why, enum bm_flag flags); |
| extern void drbd_bm_unlock(struct drbd_device *device); |
| /* 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_connection *connection); |
| extern enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor); |
| extern void drbd_destroy_device(struct kref *kref); |
| extern void drbd_delete_device(struct drbd_device *device); |
| |
| extern struct drbd_resource *drbd_create_resource(const char *name); |
| extern void drbd_free_resource(struct drbd_resource *resource); |
| |
| extern int set_resource_options(struct drbd_resource *resource, struct res_opts *res_opts); |
| extern struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts); |
| extern void drbd_destroy_connection(struct kref *kref); |
| extern struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len, |
| void *peer_addr, int peer_addr_len); |
| extern struct drbd_resource *drbd_find_resource(const char *name); |
| extern void drbd_destroy_resource(struct kref *kref); |
| extern void conn_free_crypto(struct drbd_connection *connection); |
| |
| extern int proc_details; |
| |
| /* drbd_req */ |
| extern void do_submit(struct work_struct *ws); |
| extern void __drbd_make_request(struct drbd_device *, struct bio *, unsigned long); |
| extern void drbd_make_request(struct request_queue *q, struct bio *bio); |
| extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req); |
| extern int is_valid_ar_handle(struct drbd_request *, sector_t); |
| |
| |
| /* drbd_nl.c */ |
| extern void drbd_suspend_io(struct drbd_device *device); |
| extern void drbd_resume_io(struct drbd_device *device); |
| extern char *ppsize(char *buf, unsigned long long size); |
| extern sector_t drbd_new_dev_size(struct drbd_device *, 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_device *, enum dds_flags, struct resize_parms *) __must_hold(local); |
| extern void resync_after_online_grow(struct drbd_device *); |
| extern void drbd_reconsider_max_bio_size(struct drbd_device *device, struct drbd_backing_dev *bdev); |
| extern enum drbd_state_rv drbd_set_role(struct drbd_device *device, |
| enum drbd_role new_role, |
| int force); |
| extern bool conn_try_outdate_peer(struct drbd_connection *connection); |
| extern void conn_try_outdate_peer_async(struct drbd_connection *connection); |
| extern int drbd_khelper(struct drbd_device *device, char *cmd); |
| |
| /* drbd_worker.c */ |
| /* bi_end_io handlers */ |
| extern void drbd_md_endio(struct bio *bio); |
| extern void drbd_peer_request_endio(struct bio *bio); |
| extern void drbd_request_endio(struct bio *bio); |
| extern int drbd_worker(struct drbd_thread *thi); |
| enum drbd_ret_code drbd_resync_after_valid(struct drbd_device *device, int o_minor); |
| void drbd_resync_after_changed(struct drbd_device *device); |
| extern void drbd_start_resync(struct drbd_device *device, enum drbd_conns side); |
| extern void resume_next_sg(struct drbd_device *device); |
| extern void suspend_other_sg(struct drbd_device *device); |
| extern int drbd_resync_finished(struct drbd_device *device); |
| /* maybe rather drbd_main.c ? */ |
| extern void *drbd_md_get_buffer(struct drbd_device *device, const char *intent); |
| extern void drbd_md_put_buffer(struct drbd_device *device); |
| extern int drbd_md_sync_page_io(struct drbd_device *device, |
| struct drbd_backing_dev *bdev, sector_t sector, int rw); |
| extern void drbd_ov_out_of_sync_found(struct drbd_device *, sector_t, int); |
| extern void wait_until_done_or_force_detached(struct drbd_device *device, |
| struct drbd_backing_dev *bdev, unsigned int *done); |
| extern void drbd_rs_controller_reset(struct drbd_device *device); |
| |
| static inline void ov_out_of_sync_print(struct drbd_device *device) |
| { |
| if (device->ov_last_oos_size) { |
| drbd_err(device, "Out of sync: start=%llu, size=%lu (sectors)\n", |
| (unsigned long long)device->ov_last_oos_start, |
| (unsigned long)device->ov_last_oos_size); |
| } |
| device->ov_last_oos_size = 0; |
| } |
| |
| |
| extern void drbd_csum_bio(struct crypto_hash *, struct bio *, void *); |
| extern void drbd_csum_ee(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_send_dblock(struct drbd_work *, int); |
| extern int w_send_read_req(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); |
| |
| extern void drbd_endio_write_sec_final(struct drbd_peer_request *peer_req); |
| |
| /* drbd_receiver.c */ |
| extern int drbd_receiver(struct drbd_thread *thi); |
| extern int drbd_asender(struct drbd_thread *thi); |
| extern bool drbd_rs_c_min_rate_throttle(struct drbd_device *device); |
| extern bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector, |
| bool throttle_if_app_is_waiting); |
| extern int drbd_submit_peer_request(struct drbd_device *, |
| struct drbd_peer_request *, const unsigned, |
| const int); |
| extern int drbd_free_peer_reqs(struct drbd_device *, struct list_head *); |
| extern struct drbd_peer_request *drbd_alloc_peer_req(struct drbd_peer_device *, u64, |
| sector_t, unsigned int, |
| bool, |
| gfp_t) __must_hold(local); |
| extern void __drbd_free_peer_req(struct drbd_device *, 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_peer_device *, unsigned int, bool); |
| extern void drbd_set_recv_tcq(struct drbd_device *device, int tcq_enabled); |
| extern void _drbd_clear_done_ee(struct drbd_device *device, struct list_head *to_be_freed); |
| extern int drbd_connected(struct drbd_peer_device *); |
| |
| static inline void drbd_tcp_cork(struct socket *sock) |
| { |
| int val = 1; |
| (void) kernel_setsockopt(sock, SOL_TCP, TCP_CORK, |
| (char*)&val, sizeof(val)); |
| } |
| |
| static inline void drbd_tcp_uncork(struct socket *sock) |
| { |
| int val = 0; |
| (void) kernel_setsockopt(sock, SOL_TCP, TCP_CORK, |
| (char*)&val, sizeof(val)); |
| } |
| |
| static inline void drbd_tcp_nodelay(struct socket *sock) |
| { |
| int val = 1; |
| (void) kernel_setsockopt(sock, SOL_TCP, TCP_NODELAY, |
| (char*)&val, sizeof(val)); |
| } |
| |
| static inline void drbd_tcp_quickack(struct socket *sock) |
| { |
| int val = 2; |
| (void) kernel_setsockopt(sock, SOL_TCP, TCP_QUICKACK, |
| (char*)&val, sizeof(val)); |
| } |
| |
| /* sets the number of 512 byte sectors of our virtual device */ |
| static inline void drbd_set_my_capacity(struct drbd_device *device, |
| sector_t size) |
| { |
| /* set_capacity(device->this_bdev->bd_disk, size); */ |
| set_capacity(device->vdisk, size); |
| device->this_bdev->bd_inode->i_size = (loff_t)size << 9; |
| } |
| |
| /* |
| * used to submit our private bio |
| */ |
| static inline void drbd_generic_make_request(struct drbd_device *device, |
| int fault_type, struct bio *bio) |
| { |
| __release(local); |
| if (!bio->bi_bdev) { |
| drbd_err(device, "drbd_generic_make_request: bio->bi_bdev == NULL\n"); |
| bio->bi_error = -ENODEV; |
| bio_endio(bio); |
| return; |
| } |
| |
| if (drbd_insert_fault(device, fault_type)) |
| bio_io_error(bio); |
| else |
| generic_make_request(bio); |
| } |
| |
| void drbd_bump_write_ordering(struct drbd_resource *resource, struct drbd_backing_dev *bdev, |
| 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 bool drbd_al_begin_io_prepare(struct drbd_device *device, struct drbd_interval *i); |
| extern int drbd_al_begin_io_nonblock(struct drbd_device *device, struct drbd_interval *i); |
| extern void drbd_al_begin_io_commit(struct drbd_device *device); |
| extern bool drbd_al_begin_io_fastpath(struct drbd_device *device, struct drbd_interval *i); |
| extern void drbd_al_begin_io(struct drbd_device *device, struct drbd_interval *i); |
| extern void drbd_al_complete_io(struct drbd_device *device, struct drbd_interval *i); |
| extern void drbd_rs_complete_io(struct drbd_device *device, sector_t sector); |
| extern int drbd_rs_begin_io(struct drbd_device *device, sector_t sector); |
| extern int drbd_try_rs_begin_io(struct drbd_device *device, sector_t sector); |
| extern void drbd_rs_cancel_all(struct drbd_device *device); |
| extern int drbd_rs_del_all(struct drbd_device *device); |
| extern void drbd_rs_failed_io(struct drbd_device *device, |
| sector_t sector, int size); |
| extern void drbd_advance_rs_marks(struct drbd_device *device, unsigned long still_to_go); |
| |
| enum update_sync_bits_mode { RECORD_RS_FAILED, SET_OUT_OF_SYNC, SET_IN_SYNC }; |
| extern int __drbd_change_sync(struct drbd_device *device, sector_t sector, int size, |
| enum update_sync_bits_mode mode); |
| #define drbd_set_in_sync(device, sector, size) \ |
| __drbd_change_sync(device, sector, size, SET_IN_SYNC) |
| #define drbd_set_out_of_sync(device, sector, size) \ |
| __drbd_change_sync(device, sector, size, SET_OUT_OF_SYNC) |
| #define drbd_rs_failed_io(device, sector, size) \ |
| __drbd_change_sync(device, sector, size, RECORD_RS_FAILED) |
| extern void drbd_al_shrink(struct drbd_device *device); |
| extern int drbd_initialize_al(struct drbd_device *, 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_device *device, 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_device *device, 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(device, ns, flags, done); |
| read_unlock(&global_state_lock); |
| |
| return rv; |
| } |
| |
| static inline union drbd_state drbd_read_state(struct drbd_device *device) |
| { |
| struct drbd_resource *resource = device->resource; |
| union drbd_state rv; |
| |
| rv.i = device->state.i; |
| rv.susp = resource->susp; |
| rv.susp_nod = resource->susp_nod; |
| rv.susp_fen = resource->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_device *device, |
| enum drbd_force_detach_flags df, |
| const char *where) |
| { |
| enum drbd_io_error_p ep; |
| |
| rcu_read_lock(); |
| ep = rcu_dereference(device->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)) |
| drbd_err(device, "Local IO failed in %s.\n", where); |
| if (device->state.disk > D_INCONSISTENT) |
| _drbd_set_state(_NS(device, 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, &device->flags); |
| if (df == DRBD_READ_ERROR) |
| set_bit(WAS_READ_ERROR, &device->flags); |
| if (df == DRBD_FORCE_DETACH) |
| set_bit(FORCE_DETACH, &device->flags); |
| if (device->state.disk > D_FAILED) { |
| _drbd_set_state(_NS(device, disk, D_FAILED), CS_HARD, NULL); |
| drbd_err(device, |
| "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 |
| * @device: 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_device *device, |
| int error, enum drbd_force_detach_flags forcedetach, const char *where) |
| { |
| if (error) { |
| unsigned long flags; |
| spin_lock_irqsave(&device->resource->req_lock, flags); |
| __drbd_chk_io_error_(device, forcedetach, where); |
| spin_unlock_irqrestore(&device->resource->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(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 |
| drbd_queue_work_if_unqueued(struct drbd_work_queue *q, struct drbd_work *w) |
| { |
| unsigned long flags; |
| spin_lock_irqsave(&q->q_lock, flags); |
| if (list_empty_careful(&w->list)) |
| list_add_tail(&w->list, &q->q); |
| spin_unlock_irqrestore(&q->q_lock, flags); |
| wake_up(&q->q_wait); |
| } |
| |
| static inline void |
| drbd_device_post_work(struct drbd_device *device, int work_bit) |
| { |
| if (!test_and_set_bit(work_bit, &device->flags)) { |
| struct drbd_connection *connection = |
| first_peer_device(device)->connection; |
| struct drbd_work_queue *q = &connection->sender_work; |
| if (!test_and_set_bit(DEVICE_WORK_PENDING, &connection->flags)) |
| wake_up(&q->q_wait); |
| } |
| } |
| |
| extern void drbd_flush_workqueue(struct drbd_work_queue *work_queue); |
| |
| static inline void wake_asender(struct drbd_connection *connection) |
| { |
| if (test_bit(SIGNAL_ASENDER, &connection->flags)) |
| force_sig(DRBD_SIG, connection->asender.task); |
| } |
| |
| static inline void request_ping(struct drbd_connection *connection) |
| { |
| set_bit(SEND_PING, &connection->flags); |
| wake_asender(connection); |
| } |
| |
| extern void *conn_prepare_command(struct drbd_connection *, struct drbd_socket *); |
| extern void *drbd_prepare_command(struct drbd_peer_device *, struct drbd_socket *); |
| extern int conn_send_command(struct drbd_connection *, struct drbd_socket *, |
| enum drbd_packet, unsigned int, void *, |
| unsigned int); |
| extern int drbd_send_command(struct drbd_peer_device *, struct drbd_socket *, |
| enum drbd_packet, unsigned int, void *, |
| unsigned int); |
| |
| extern int drbd_send_ping(struct drbd_connection *connection); |
| extern int drbd_send_ping_ack(struct drbd_connection *connection); |
| extern int drbd_send_state_req(struct drbd_peer_device *, union drbd_state, union drbd_state); |
| extern int conn_send_state_req(struct drbd_connection *, 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_device *device) |
| { |
| atomic_inc(&device->ap_pending_cnt); |
| } |
| |
| #define ERR_IF_CNT_IS_NEGATIVE(which, func, line) \ |
| if (atomic_read(&device->which) < 0) \ |
| drbd_err(device, "in %s:%d: " #which " = %d < 0 !\n", \ |
| func, line, \ |
| atomic_read(&device->which)) |
| |
| #define dec_ap_pending(device) _dec_ap_pending(device, __func__, __LINE__) |
| static inline void _dec_ap_pending(struct drbd_device *device, const char *func, int line) |
| { |
| if (atomic_dec_and_test(&device->ap_pending_cnt)) |
| wake_up(&device->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_device *device) |
| { |
| atomic_inc(&device->rs_pending_cnt); |
| } |
| |
| #define dec_rs_pending(device) _dec_rs_pending(device, __func__, __LINE__) |
| static inline void _dec_rs_pending(struct drbd_device *device, const char *func, int line) |
| { |
| atomic_dec(&device->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_device *device) |
| { |
| atomic_inc(&device->unacked_cnt); |
| } |
| |
| #define dec_unacked(device) _dec_unacked(device, __func__, __LINE__) |
| static inline void _dec_unacked(struct drbd_device *device, const char *func, int line) |
| { |
| atomic_dec(&device->unacked_cnt); |
| ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); |
| } |
| |
| #define sub_unacked(device, n) _sub_unacked(device, n, __func__, __LINE__) |
| static inline void _sub_unacked(struct drbd_device *device, int n, const char *func, int line) |
| { |
| atomic_sub(n, &device->unacked_cnt); |
| ERR_IF_CNT_IS_NEGATIVE(unacked_cnt, func, line); |
| } |
| |
| static inline bool is_sync_state(enum drbd_conns connection_state) |
| { |
| return |
| (connection_state == C_SYNC_SOURCE |
| || connection_state == C_SYNC_TARGET |
| || connection_state == C_PAUSED_SYNC_S |
| || connection_state == C_PAUSED_SYNC_T); |
| } |
| |
| /** |
| * get_ldev() - Increase the ref count on device->ldev. Returns 0 if there is no ldev |
| * @_device: DRBD device. |
| * @_min_state: Minimum device state required for success. |
| * |
| * You have to call put_ldev() when finished working with device->ldev. |
| */ |
| #define get_ldev_if_state(_device, _min_state) \ |
| (_get_ldev_if_state((_device), (_min_state)) ? \ |
| ({ __acquire(x); true; }) : false) |
| #define get_ldev(_device) get_ldev_if_state(_device, D_INCONSISTENT) |
| |
| static inline void put_ldev(struct drbd_device *device) |
| { |
| enum drbd_disk_state disk_state = device->state.disk; |
| /* We must check the state *before* the atomic_dec becomes visible, |
| * or we have a theoretical race where someone hitting zero, |
| * while state still D_FAILED, will then see D_DISKLESS in the |
| * condition below and calling into destroy, where he must not, yet. */ |
| int i = atomic_dec_return(&device->local_cnt); |
| |
| /* This may be called from some endio handler, |
| * so we must not sleep here. */ |
| |
| __release(local); |
| D_ASSERT(device, i >= 0); |
| if (i == 0) { |
| if (disk_state == D_DISKLESS) |
| /* even internal references gone, safe to destroy */ |
| drbd_device_post_work(device, DESTROY_DISK); |
| if (disk_state == D_FAILED) |
| /* all application IO references gone. */ |
| if (!test_and_set_bit(GOING_DISKLESS, &device->flags)) |
| drbd_device_post_work(device, GO_DISKLESS); |
| wake_up(&device->misc_wait); |
| } |
| } |
| |
| #ifndef __CHECKER__ |
| static inline int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins) |
| { |
| int io_allowed; |
| |
| /* never get a reference while D_DISKLESS */ |
| if (device->state.disk == D_DISKLESS) |
| return 0; |
| |
| atomic_inc(&device->local_cnt); |
| io_allowed = (device->state.disk >= mins); |
| if (!io_allowed) |
| put_ldev(device); |
| return io_allowed; |
| } |
| #else |
| extern int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins); |
| #endif |
| |
| /* 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_device *device) |
| { |
| struct net_conf *nc; |
| int mxb; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(first_peer_device(device)->connection->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_device *device) |
| { |
| union drbd_dev_state s = device->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 (first_peer_device(device)->connection->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_device *device) |
| { |
| struct drbd_resource *resource = device->resource; |
| |
| return resource->susp || resource->susp_fen || resource->susp_nod; |
| } |
| |
| static inline bool may_inc_ap_bio(struct drbd_device *device) |
| { |
| int mxb = drbd_get_max_buffers(device); |
| |
| if (drbd_suspended(device)) |
| return false; |
| if (test_bit(SUSPEND_IO, &device->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(device)) |
| 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(&device->ap_bio_cnt) > mxb) |
| return false; |
| if (test_bit(BITMAP_IO, &device->flags)) |
| return false; |
| return true; |
| } |
| |
| static inline bool inc_ap_bio_cond(struct drbd_device *device) |
| { |
| bool rv = false; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| rv = may_inc_ap_bio(device); |
| if (rv) |
| atomic_inc(&device->ap_bio_cnt); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| return rv; |
| } |
| |
| static inline void inc_ap_bio(struct drbd_device *device) |
| { |
| /* 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(device->misc_wait, inc_ap_bio_cond(device)); |
| } |
| |
| static inline void dec_ap_bio(struct drbd_device *device) |
| { |
| int mxb = drbd_get_max_buffers(device); |
| int ap_bio = atomic_dec_return(&device->ap_bio_cnt); |
| |
| D_ASSERT(device, ap_bio >= 0); |
| |
| if (ap_bio == 0 && test_bit(BITMAP_IO, &device->flags)) { |
| if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) |
| drbd_queue_work(&first_peer_device(device)-> |
| connection->sender_work, |
| &device->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(&device->misc_wait); |
| } |
| |
| static inline bool verify_can_do_stop_sector(struct drbd_device *device) |
| { |
| return first_peer_device(device)->connection->agreed_pro_version >= 97 && |
| first_peer_device(device)->connection->agreed_pro_version != 100; |
| } |
| |
| static inline int drbd_set_ed_uuid(struct drbd_device *device, u64 val) |
| { |
| int changed = device->ed_uuid != val; |
| device->ed_uuid = val; |
| return changed; |
| } |
| |
| static inline int drbd_queue_order_type(struct drbd_device *device) |
| { |
| /* 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 struct drbd_connection *first_connection(struct drbd_resource *resource) |
| { |
| return list_first_entry_or_null(&resource->connections, |
| struct drbd_connection, connections); |
| } |
| |
| #endif |