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Subject[PATCH 08/16] DRBD: main
Date
The DRBD state engine, and lots of other stuff, that does not have its own
source file.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

---
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
new file mode 100644
index 0000000..ad29684
--- /dev/null
+++ b/drivers/block/drbd/drbd_main.c
@@ -0,0 +1,3669 @@
+/*
+ drbd.c
+
+ 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.
+
+ */
+
+#include <linux/autoconf.h>
+#include <linux/module.h>
+#include <linux/version.h>
+
+#include <asm/uaccess.h>
+#include <asm/types.h>
+#include <net/sock.h>
+#include <linux/ctype.h>
+#include <linux/smp_lock.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/drbd_config.h>
+#include <linux/memcontrol.h>
+#include <linux/mm_inline.h>
+#include <linux/slab.h>
+#include <linux/random.h>
+#include <linux/reboot.h>
+#include <linux/notifier.h>
+#include <linux/kthread.h>
+
+#define __KERNEL_SYSCALLS__
+#include <linux/unistd.h>
+#include <linux/vmalloc.h>
+
+#include <linux/drbd.h>
+#include <linux/drbd_limits.h>
+#include "drbd_int.h"
+#include "drbd_tracing.h"
+#include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */
+
+#include "drbd_vli.h"
+
+struct after_state_chg_work {
+ struct drbd_work w;
+ union drbd_state os;
+ union drbd_state ns;
+ enum chg_state_flags flags;
+ struct completion *done;
+};
+
+int drbdd_init(struct drbd_thread *);
+int drbd_worker(struct drbd_thread *);
+int drbd_asender(struct drbd_thread *);
+
+int drbd_init(void);
+static int drbd_open(struct block_device *bdev, fmode_t mode);
+static int drbd_release(struct gendisk *gd, fmode_t mode);
+STATIC int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused);
+STATIC void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
+ union drbd_state ns, enum chg_state_flags flags);
+STATIC int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused);
+STATIC void md_sync_timer_fn(unsigned long data);
+STATIC int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused);
+
+DEFINE_TRACE(drbd_unplug);
+DEFINE_TRACE(drbd_uuid);
+DEFINE_TRACE(drbd_ee);
+DEFINE_TRACE(drbd_packet);
+DEFINE_TRACE(drbd_md_io);
+DEFINE_TRACE(drbd_epoch);
+DEFINE_TRACE(drbd_netlink);
+DEFINE_TRACE(drbd_actlog);
+DEFINE_TRACE(drbd_bio);
+DEFINE_TRACE(_drbd_resync);
+DEFINE_TRACE(drbd_req);
+
+MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
+ "Lars Ellenberg <lars@linbit.com>");
+MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_PARM_DESC(minor_count, "Maximum number of drbd devices (1-255)");
+MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);
+
+#include <linux/moduleparam.h>
+/* allow_open_on_secondary */
+MODULE_PARM_DESC(allow_oos, "DONT USE!");
+/* thanks to these macros, if compiled into the kernel (not-module),
+ * this becomes the boot parameter drbd.minor_count */
+module_param(minor_count, uint, 0444);
+module_param(disable_sendpage, bool, 0644);
+module_param(allow_oos, bool, 0);
+module_param(cn_idx, uint, 0444);
+module_param(proc_details, int, 0644);
+
+#ifdef DRBD_ENABLE_FAULTS
+int enable_faults;
+int fault_rate;
+static int fault_count;
+int fault_devs;
+/* bitmap of enabled faults */
+module_param(enable_faults, int, 0664);
+/* fault rate % value - applies to all enabled faults */
+module_param(fault_rate, int, 0664);
+/* count of faults inserted */
+module_param(fault_count, int, 0664);
+/* bitmap of devices to insert faults on */
+module_param(fault_devs, int, 0644);
+#endif
+
+/* module parameter, defined */
+unsigned int minor_count = 32;
+int disable_sendpage;
+int allow_oos;
+unsigned int cn_idx = CN_IDX_DRBD;
+int proc_details; /* Detail level in proc drbd*/
+
+/* Module parameter for setting the user mode helper program
+ * to run. Default is /sbin/drbdadm */
+char usermode_helper[80] = "/sbin/drbdadm";
+
+module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);
+
+/* in 2.6.x, our device mapping and config info contains our virtual gendisks
+ * as member "struct gendisk *vdisk;"
+ */
+struct drbd_conf **minor_table;
+
+struct kmem_cache *drbd_request_cache;
+struct kmem_cache *drbd_ee_cache;
+mempool_t *drbd_request_mempool;
+mempool_t *drbd_ee_mempool;
+
+/* I do not use a standard mempool, because:
+ 1) I want to hand out the preallocated objects first.
+ 2) I want to be able to interrupt sleeping allocation with a signal.
+ Note: This is a single linked list, the next pointer is the private
+ member of struct page.
+ */
+struct page *drbd_pp_pool;
+spinlock_t drbd_pp_lock;
+int drbd_pp_vacant;
+wait_queue_head_t drbd_pp_wait;
+
+DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);
+
+STATIC struct block_device_operations drbd_ops = {
+ .owner = THIS_MODULE,
+ .open = drbd_open,
+ .release = drbd_release,
+};
+
+#define ARRY_SIZE(A) (sizeof(A)/sizeof(A[0]))
+
+#ifdef __CHECKER__
+/* When checking with sparse, and this is an inline function, sparse will
+ give tons of false positives. When this is a real functions sparse works.
+ */
+int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
+{
+ int io_allowed;
+
+ atomic_inc(&mdev->local_cnt);
+ io_allowed = (mdev->state.disk >= mins);
+ if (!io_allowed) {
+ if (atomic_dec_and_test(&mdev->local_cnt))
+ wake_up(&mdev->misc_wait);
+ }
+ return io_allowed;
+}
+
+#endif
+
+/**
+ * DOC: The transfer log
+ *
+ * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
+ * mdev->newest_tle points to the head, mdev->oldest_tle points to the tail
+ * of the list. There is always at least one &struct drbd_tl_epoch object.
+ *
+ * Each &struct drbd_tl_epoch has a circular double linked list of requests
+ * attached.
+ */
+STATIC int tl_init(struct drbd_conf *mdev)
+{
+ struct drbd_tl_epoch *b;
+
+ b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
+ if (!b)
+ return 0;
+ INIT_LIST_HEAD(&b->requests);
+ INIT_LIST_HEAD(&b->w.list);
+ b->next = NULL;
+ b->br_number = 4711;
+ b->n_req = 0;
+ b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
+
+ mdev->oldest_tle = b;
+ mdev->newest_tle = b;
+ INIT_LIST_HEAD(&mdev->out_of_sequence_requests);
+
+ mdev->tl_hash = NULL;
+ mdev->tl_hash_s = 0;
+
+ return 1;
+}
+
+STATIC void tl_cleanup(struct drbd_conf *mdev)
+{
+ D_ASSERT(mdev->oldest_tle == mdev->newest_tle);
+ D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
+ kfree(mdev->oldest_tle);
+ mdev->oldest_tle = NULL;
+ kfree(mdev->unused_spare_tle);
+ mdev->unused_spare_tle = NULL;
+ kfree(mdev->tl_hash);
+ mdev->tl_hash = NULL;
+ mdev->tl_hash_s = 0;
+}
+
+/**
+ * _tl_add_barrier() - Adds a barrier to the transfer log
+ * @mdev: DRBD device.
+ * @new: Barrier to be added before the current head of the TL.
+ *
+ * The caller must hold the req_lock.
+ */
+void _tl_add_barrier(struct drbd_conf *mdev, struct drbd_tl_epoch *new)
+{
+ struct drbd_tl_epoch *newest_before;
+
+ INIT_LIST_HEAD(&new->requests);
+ INIT_LIST_HEAD(&new->w.list);
+ new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
+ new->next = NULL;
+ new->n_req = 0;
+
+ newest_before = mdev->newest_tle;
+ /* never send a barrier number == 0, because that is special-cased
+ * when using TCQ for our write ordering code */
+ new->br_number = (newest_before->br_number+1) ?: 1;
+ if (mdev->newest_tle != new) {
+ mdev->newest_tle->next = new;
+ mdev->newest_tle = new;
+ }
+}
+
+/**
+ * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
+ * @mdev: DRBD device.
+ * @barrier_nr: Expected identifier of the DRBD write barrier packet.
+ * @set_size: Expected number of requests before that barrier.
+ *
+ * In case the passed barrier_nr or set_size does not match the oldest
+ * &struct drbd_tl_epoch objects this function will cause a termination
+ * of the connection.
+ */
+void tl_release(struct drbd_conf *mdev, unsigned int barrier_nr,
+ unsigned int set_size)
+{
+ struct drbd_tl_epoch *b, *nob; /* next old barrier */
+ struct list_head *le, *tle;
+ struct drbd_request *r;
+
+ spin_lock_irq(&mdev->req_lock);
+
+ b = mdev->oldest_tle;
+
+ /* first some paranoia code */
+ if (b == NULL) {
+ dev_err(DEV, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
+ barrier_nr);
+ goto bail;
+ }
+ if (b->br_number != barrier_nr) {
+ dev_err(DEV, "BAD! BarrierAck #%u received, expected #%u!\n",
+ barrier_nr, b->br_number);
+ goto bail;
+ }
+ if (b->n_req != set_size) {
+ dev_err(DEV, "BAD! BarrierAck #%u received with n_req=%u, expected n_req=%u!\n",
+ barrier_nr, set_size, b->n_req);
+ goto bail;
+ }
+
+ /* Clean up list of requests processed during current epoch */
+ list_for_each_safe(le, tle, &b->requests) {
+ r = list_entry(le, struct drbd_request, tl_requests);
+ _req_mod(r, barrier_acked, 0);
+ }
+ /* There could be requests on the list waiting for completion
+ of the write to the local disk. To avoid corruptions of
+ slab's data structures we have to remove the lists head.
+
+ Also there could have been a barrier ack out of sequence, overtaking
+ the write acks - which would be a but and violating write ordering.
+ To not deadlock in case we lose connection while such requests are
+ still pending, we need some way to find them for the
+ _req_mode(connection_lost_while_pending).
+
+ These have been list_move'd to the out_of_sequence_requests list in
+ _req_mod(, barrier_acked,) above.
+ */
+ list_del_init(&b->requests);
+
+ nob = b->next;
+ if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
+ _tl_add_barrier(mdev, b);
+ if (nob)
+ mdev->oldest_tle = nob;
+ /* if nob == NULL b was the only barrier, and becomes the new
+ barrer. Threfore mdev->oldest_tle points already to b */
+ } else {
+ D_ASSERT(nob != NULL);
+ mdev->oldest_tle = nob;
+ kfree(b);
+ }
+
+ spin_unlock_irq(&mdev->req_lock);
+ dec_ap_pending(mdev);
+
+ return;
+
+bail:
+ spin_unlock_irq(&mdev->req_lock);
+ drbd_force_state(mdev, NS(conn, C_PROTOCOL_ERROR));
+}
+
+
+/**
+ * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
+ * @mdev: DRBD device.
+ *
+ * This is called after the connection to the peer was lost. The storage covered
+ * by the requests on the transfer gets marked as our of sync. Called from the
+ * receiver thread and the worker thread.
+ */
+void tl_clear(struct drbd_conf *mdev)
+{
+ struct drbd_tl_epoch *b, *tmp;
+ struct list_head *le, *tle;
+ struct drbd_request *r;
+ int new_initial_bnr = net_random();
+
+ spin_lock_irq(&mdev->req_lock);
+
+ b = mdev->oldest_tle;
+ while (b) {
+ list_for_each_safe(le, tle, &b->requests) {
+ r = list_entry(le, struct drbd_request, tl_requests);
+ _req_mod(r, connection_lost_while_pending, 0);
+ }
+ tmp = b->next;
+
+ /* there could still be requests on that ring list,
+ * in case local io is still pending */
+ list_del(&b->requests);
+
+ /* dec_ap_pending corresponding to queue_barrier.
+ * the newest barrier may not have been queued yet,
+ * in which case w.cb is still NULL. */
+ if (b->w.cb != NULL)
+ dec_ap_pending(mdev);
+
+ if (b == mdev->newest_tle) {
+ /* recycle, but reinit! */
+ D_ASSERT(tmp == NULL);
+ INIT_LIST_HEAD(&b->requests);
+ INIT_LIST_HEAD(&b->w.list);
+ b->w.cb = NULL;
+ b->br_number = new_initial_bnr;
+ b->n_req = 0;
+
+ mdev->oldest_tle = b;
+ break;
+ }
+ kfree(b);
+ b = tmp;
+ }
+
+ /* we expect this list to be empty. */
+ D_ASSERT(list_empty(&mdev->out_of_sequence_requests));
+
+ /* but just in case, clean it up anyways! */
+ list_for_each_safe(le, tle, &mdev->out_of_sequence_requests) {
+ r = list_entry(le, struct drbd_request, tl_requests);
+ _req_mod(r, connection_lost_while_pending, 0);
+ }
+
+ /* ensure bit indicating barrier is required is clear */
+ clear_bit(CREATE_BARRIER, &mdev->flags);
+
+ spin_unlock_irq(&mdev->req_lock);
+}
+
+/**
+ * drbd_io_error() - Detach from the local disk of so configured with the on_io_error setting
+ * @mdev: DRBD device.
+ * @force_detach: Detach no matter how on_io_error is set (meta data IO error)
+ *
+ * Should be called in the unlikely(!drbd_bio_uptodate(e->bio)) case from
+ * kernel thread context. See also drbd_chk_io_error().
+ */
+int drbd_io_error(struct drbd_conf *mdev, int force_detach)
+{
+ enum drbd_io_error_p eh;
+ unsigned long flags;
+ int send;
+ int ok = 1;
+
+ eh = EP_PASS_ON;
+ if (get_ldev_if_state(mdev, D_FAILED)) {
+ eh = mdev->ldev->dc.on_io_error;
+ put_ldev(mdev);
+ }
+
+ if (!force_detach && eh == EP_PASS_ON)
+ return 1;
+
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ send = (mdev->state.disk == D_FAILED);
+ if (send)
+ _drbd_set_state(_NS(mdev, disk, D_DISKLESS), CS_HARD, NULL);
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ if (!send)
+ return ok;
+
+ if (mdev->state.conn >= C_CONNECTED) {
+ ok = drbd_send_state(mdev);
+ if (ok)
+ dev_warn(DEV, "Notified peer that my disk is broken.\n");
+ else
+ dev_err(DEV, "Sending state in drbd_io_error() failed\n");
+ }
+
+ /* Make sure we try to flush meta-data to disk - we come
+ * in here because of a local disk error so it might fail
+ * but we still need to try -- both because the error might
+ * be in the data portion of the disk and because we need
+ * to ensure the md-sync-timer is stopped if running. */
+ drbd_md_sync(mdev);
+
+ /* Releasing the backing device is done in after_state_ch() */
+
+ if (eh == EP_CALL_HELPER)
+ drbd_khelper(mdev, "local-io-error");
+
+ return ok;
+}
+
+/**
+ * cl_wide_st_chg() - TRUE if the state change is a cluster wide one
+ * @mdev: DRBD device.
+ * @os: old (current) state.
+ * @ns: new (wanted) state.
+ */
+STATIC int cl_wide_st_chg(struct drbd_conf *mdev,
+ union drbd_state os, union drbd_state ns)
+{
+ return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED &&
+ ((os.role != R_PRIMARY && ns.role == R_PRIMARY) ||
+ (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
+ (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) ||
+ (os.disk != D_DISKLESS && ns.disk == D_DISKLESS))) ||
+ (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) ||
+ (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S);
+}
+
+int drbd_change_state(struct drbd_conf *mdev, enum chg_state_flags f,
+ union drbd_state mask, union drbd_state val)
+{
+ unsigned long flags;
+ union drbd_state os, ns;
+ int rv;
+
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ os = mdev->state;
+ ns.i = (os.i & ~mask.i) | val.i;
+ rv = _drbd_set_state(mdev, ns, f, NULL);
+ ns = mdev->state;
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ return rv;
+}
+
+/**
+ * drbd_force_state() - Impose a change which happens outside our control on our state
+ * @mdev: DRBD device.
+ * @mask: mask of state bits to change.
+ * @val: value of new state bits.
+ */
+void drbd_force_state(struct drbd_conf *mdev,
+ union drbd_state mask, union drbd_state val)
+{
+ drbd_change_state(mdev, CS_HARD, mask, val);
+}
+
+STATIC int is_valid_state(struct drbd_conf *mdev, union drbd_state ns);
+STATIC int is_valid_state_transition(struct drbd_conf *,
+ union drbd_state, union drbd_state);
+STATIC union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
+ union drbd_state ns, int *warn_sync_abort);
+int drbd_send_state_req(struct drbd_conf *,
+ union drbd_state, union drbd_state);
+
+STATIC enum drbd_state_ret_codes _req_st_cond(struct drbd_conf *mdev,
+ union drbd_state mask, union drbd_state val)
+{
+ union drbd_state os, ns;
+ unsigned long flags;
+ int rv;
+
+ if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &mdev->flags))
+ return SS_CW_SUCCESS;
+
+ if (test_and_clear_bit(CL_ST_CHG_FAIL, &mdev->flags))
+ return SS_CW_FAILED_BY_PEER;
+
+ rv = 0;
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ os = mdev->state;
+ ns.i = (os.i & ~mask.i) | val.i;
+ ns = sanitize_state(mdev, os, ns, NULL);
+
+ if (!cl_wide_st_chg(mdev, os, ns))
+ rv = SS_CW_NO_NEED;
+ if (!rv) {
+ rv = is_valid_state(mdev, ns);
+ if (rv == SS_SUCCESS) {
+ rv = is_valid_state_transition(mdev, ns, os);
+ if (rv == SS_SUCCESS)
+ rv = 0; /* cont waiting, otherwise fail. */
+ }
+ }
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ return rv;
+}
+
+/**
+ * drbd_req_state() - Perform an eventually cluster wide state change
+ * @mdev: DRBD device.
+ * @mask: mask of state bits to change.
+ * @val: value of new state bits.
+ * @f: flags
+ *
+ * Should not be called directly, use drbd_request_state() or
+ * _drbd_request_state().
+ */
+STATIC int drbd_req_state(struct drbd_conf *mdev,
+ union drbd_state mask, union drbd_state val,
+ enum chg_state_flags f)
+{
+ struct completion done;
+ unsigned long flags;
+ union drbd_state os, ns;
+ int rv;
+
+ init_completion(&done);
+
+ if (f & CS_SERIALIZE)
+ mutex_lock(&mdev->state_mutex);
+
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ os = mdev->state;
+ ns.i = (os.i & ~mask.i) | val.i;
+ ns = sanitize_state(mdev, os, ns, NULL);
+
+ if (cl_wide_st_chg(mdev, os, ns)) {
+ rv = is_valid_state(mdev, ns);
+ if (rv == SS_SUCCESS)
+ rv = is_valid_state_transition(mdev, ns, os);
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ if (rv < SS_SUCCESS) {
+ if (f & CS_VERBOSE)
+ print_st_err(mdev, os, ns, rv);
+ goto abort;
+ }
+
+ drbd_state_lock(mdev);
+ if (!drbd_send_state_req(mdev, mask, val)) {
+ drbd_state_unlock(mdev);
+ rv = SS_CW_FAILED_BY_PEER;
+ if (f & CS_VERBOSE)
+ print_st_err(mdev, os, ns, rv);
+ goto abort;
+ }
+
+ wait_event(mdev->state_wait,
+ (rv = _req_st_cond(mdev, mask, val)));
+
+ if (rv < SS_SUCCESS) {
+ drbd_state_unlock(mdev);
+ if (f & CS_VERBOSE)
+ print_st_err(mdev, os, ns, rv);
+ goto abort;
+ }
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ os = mdev->state;
+ ns.i = (os.i & ~mask.i) | val.i;
+ rv = _drbd_set_state(mdev, ns, f, &done);
+ drbd_state_unlock(mdev);
+ } else {
+ rv = _drbd_set_state(mdev, ns, f, &done);
+ }
+
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) {
+ D_ASSERT(current != mdev->worker.task);
+ wait_for_completion(&done);
+ }
+
+abort:
+ if (f & CS_SERIALIZE)
+ mutex_unlock(&mdev->state_mutex);
+
+ return rv;
+}
+
+/**
+ * _drbd_request_state() - Reqest a state change (with flags)
+ * @mdev: DRBD device.
+ * @mask: mask of state bits to change.
+ * @val: value of new state bits.
+ * @f: flags
+ *
+ * Cousin of drbd_request_state(), use full with the CS_WAIT_COMPLETE
+ * flag, or when logging of failed state change requests is not desired.
+ */
+int _drbd_request_state(struct drbd_conf *mdev, union drbd_state mask,
+ union drbd_state val, enum chg_state_flags f)
+{
+ int rv;
+
+ wait_event(mdev->state_wait,
+ (rv = drbd_req_state(mdev, mask, val, f)) != SS_IN_TRANSIENT_STATE);
+
+ return rv;
+}
+
+STATIC void print_st(struct drbd_conf *mdev, char *name, union drbd_state ns)
+{
+ dev_err(DEV, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c }\n",
+ name,
+ conns_to_name(ns.conn),
+ roles_to_name(ns.role),
+ roles_to_name(ns.peer),
+ disks_to_name(ns.disk),
+ disks_to_name(ns.pdsk),
+ ns.susp ? 's' : 'r',
+ ns.aftr_isp ? 'a' : '-',
+ ns.peer_isp ? 'p' : '-',
+ ns.user_isp ? 'u' : '-'
+ );
+}
+
+void print_st_err(struct drbd_conf *mdev,
+ union drbd_state os, union drbd_state ns, int err)
+{
+ if (err == SS_IN_TRANSIENT_STATE)
+ return;
+ dev_err(DEV, "State change failed: %s\n", set_st_err_name(err));
+ print_st(mdev, " state", os);
+ print_st(mdev, "wanted", ns);
+}
+
+
+#define peers_to_name roles_to_name
+#define pdsks_to_name disks_to_name
+
+#define susps_to_name(A) ((A) ? "1" : "0")
+#define aftr_isps_to_name(A) ((A) ? "1" : "0")
+#define peer_isps_to_name(A) ((A) ? "1" : "0")
+#define user_isps_to_name(A) ((A) ? "1" : "0")
+
+#define PSC(A) \
+ ({ if (ns.A != os.A) { \
+ pbp += sprintf(pbp, #A "( %s -> %s ) ", \
+ A##s_to_name(os.A), \
+ A##s_to_name(ns.A)); \
+ } })
+
+/**
+ * is_valid_state() - Returns an SS_ error code if ns is not valid
+ * @mdev: DRBD device.
+ * @ns: State to consider.
+ */
+STATIC int is_valid_state(struct drbd_conf *mdev, union drbd_state ns)
+{
+ /* See drbd_state_sw_errors in drbd_strings.c */
+
+ enum drbd_fencing_p fp;
+ int rv = SS_SUCCESS;
+
+ fp = FP_DONT_CARE;
+ if (get_ldev(mdev)) {
+ fp = mdev->ldev->dc.fencing;
+ put_ldev(mdev);
+ }
+
+ if (get_net_conf(mdev)) {
+ if (!mdev->net_conf->two_primaries &&
+ ns.role == R_PRIMARY && ns.peer == R_PRIMARY)
+ rv = SS_TWO_PRIMARIES;
+ put_net_conf(mdev);
+ }
+
+ if (rv <= 0)
+ /* already found a reason to abort */;
+ else if (ns.role == R_SECONDARY && mdev->open_cnt)
+ rv = SS_DEVICE_IN_USE;
+
+ else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE)
+ rv = SS_NO_UP_TO_DATE_DISK;
+
+ else if (fp >= FP_RESOURCE &&
+ ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN)
+ rv = SS_PRIMARY_NOP;
+
+ else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT)
+ rv = SS_NO_UP_TO_DATE_DISK;
+
+ else if (ns.conn > C_CONNECTED && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)
+ rv = SS_BOTH_INCONSISTENT;
+
+ else if (ns.conn > C_CONNECTED && (ns.disk == D_DISKLESS || ns.pdsk == D_DISKLESS))
+ rv = SS_SYNCING_DISKLESS;
+
+ else if ((ns.conn == C_CONNECTED ||
+ ns.conn == C_WF_BITMAP_S ||
+ ns.conn == C_SYNC_SOURCE ||
+ ns.conn == C_PAUSED_SYNC_S) &&
+ ns.disk == D_OUTDATED)
+ rv = SS_CONNECTED_OUTDATES;
+
+ else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
+ (mdev->sync_conf.verify_alg[0] == 0))
+ rv = SS_NO_VERIFY_ALG;
+
+ else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
+ mdev->agreed_pro_version < 88)
+ rv = SS_NOT_SUPPORTED;
+
+ return rv;
+}
+
+/**
+ * is_valid_state_transition() - Returns an SS_ error code if the state transition is not possible
+ * @mdev: DRBD device.
+ * @ns: new state.
+ * @os: old state.
+ */
+STATIC int is_valid_state_transition(struct drbd_conf *mdev,
+ union drbd_state ns, union drbd_state os)
+{
+ int rv = SS_SUCCESS;
+
+ if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) &&
+ os.conn > C_CONNECTED)
+ rv = SS_RESYNC_RUNNING;
+
+ if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE)
+ rv = SS_ALREADY_STANDALONE;
+
+ if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS)
+ rv = SS_IS_DISKLESS;
+
+ if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED)
+ rv = SS_NO_NET_CONFIG;
+
+ if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING)
+ rv = SS_LOWER_THAN_OUTDATED;
+
+ if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED)
+ rv = SS_IN_TRANSIENT_STATE;
+
+ if (ns.conn == os.conn && ns.conn == C_WF_REPORT_PARAMS)
+ rv = SS_IN_TRANSIENT_STATE;
+
+ if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED)
+ rv = SS_NEED_CONNECTION;
+
+ if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) &&
+ ns.conn != os.conn && os.conn > C_CONNECTED)
+ rv = SS_RESYNC_RUNNING;
+
+ if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) &&
+ os.conn < C_CONNECTED)
+ rv = SS_NEED_CONNECTION;
+
+ return rv;
+}
+
+/**
+ * sanitize_state() - Resolves implicitly necessary additional changes to a state transition
+ * @mdev: DRBD device.
+ * @os: old state.
+ * @ns: new state.
+ * @warn_sync_abort:
+ *
+ * When we loose connection, we have to set the state of the peers disk (pdsk)
+ * to D_UNKNOWN. This rule and many more along those lines are in this function.
+ */
+STATIC union drbd_state sanitize_state(struct drbd_conf *mdev, union drbd_state os,
+ union drbd_state ns, int *warn_sync_abort)
+{
+ enum drbd_fencing_p fp;
+
+ fp = FP_DONT_CARE;
+ if (get_ldev(mdev)) {
+ fp = mdev->ldev->dc.fencing;
+ put_ldev(mdev);
+ }
+
+ /* Dissalow Network errors to configure a device's network part */
+ if ((ns.conn >= C_TIMEOUT && ns.conn <= C_TEAR_DOWN) &&
+ os.conn <= C_DISCONNECTING)
+ ns.conn = os.conn;
+
+ /* After a network error (+C_TEAR_DOWN) only C_UNCONNECTED or C_DISCONNECTING can follow */
+ if (os.conn >= C_TIMEOUT && os.conn <= C_TEAR_DOWN &&
+ ns.conn != C_UNCONNECTED && ns.conn != C_DISCONNECTING)
+ ns.conn = os.conn;
+
+ /* After C_DISCONNECTING only C_STANDALONE may follow */
+ if (os.conn == C_DISCONNECTING && ns.conn != C_STANDALONE)
+ ns.conn = os.conn;
+
+ if (ns.conn < C_CONNECTED) {
+ ns.peer_isp = 0;
+ ns.peer = R_UNKNOWN;
+ if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT)
+ ns.pdsk = D_UNKNOWN;
+ }
+
+ /* Clear the aftr_isp when becoming unconfigured */
+ if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY)
+ ns.aftr_isp = 0;
+
+ if (ns.conn <= C_DISCONNECTING && ns.disk == D_DISKLESS)
+ ns.pdsk = D_UNKNOWN;
+
+ /* Abort resync if a disk fails/detaches */
+ if (os.conn > C_CONNECTED && ns.conn > C_CONNECTED &&
+ (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) {
+ if (warn_sync_abort)
+ *warn_sync_abort = 1;
+ ns.conn = C_CONNECTED;
+ }
+
+ if (ns.conn >= C_CONNECTED &&
+ ((ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) ||
+ (ns.disk == D_NEGOTIATING && ns.conn == C_WF_BITMAP_T))) {
+ switch (ns.conn) {
+ case C_WF_BITMAP_T:
+ case C_PAUSED_SYNC_T:
+ ns.disk = D_OUTDATED;
+ break;
+ case C_CONNECTED:
+ case C_WF_BITMAP_S:
+ case C_SYNC_SOURCE:
+ case C_PAUSED_SYNC_S:
+ ns.disk = D_UP_TO_DATE;
+ break;
+ case C_SYNC_TARGET:
+ ns.disk = D_INCONSISTENT;
+ dev_warn(DEV, "Implicitly set disk state Inconsistent!\n");
+ break;
+ }
+ if (os.disk == D_OUTDATED && ns.disk == D_UP_TO_DATE)
+ dev_warn(DEV, "Implicitly set disk from Outdated to UpToDate\n");
+ }
+
+ if (ns.conn >= C_CONNECTED &&
+ (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED)) {
+ switch (ns.conn) {
+ case C_CONNECTED:
+ case C_WF_BITMAP_T:
+ case C_PAUSED_SYNC_T:
+ case C_SYNC_TARGET:
+ ns.pdsk = D_UP_TO_DATE;
+ break;
+ case C_WF_BITMAP_S:
+ case C_PAUSED_SYNC_S:
+ ns.pdsk = D_OUTDATED;
+ break;
+ case C_SYNC_SOURCE:
+ ns.pdsk = D_INCONSISTENT;
+ dev_warn(DEV, "Implicitly set pdsk Inconsistent!\n");
+ break;
+ }
+ if (os.pdsk == D_OUTDATED && ns.pdsk == D_UP_TO_DATE)
+ dev_warn(DEV, "Implicitly set pdsk from Outdated to UpToDate\n");
+ }
+
+ /* Connection breaks down before we finished "Negotiating" */
+ if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING &&
+ get_ldev_if_state(mdev, D_NEGOTIATING)) {
+ if (mdev->ed_uuid == mdev->ldev->md.uuid[UI_CURRENT]) {
+ ns.disk = mdev->new_state_tmp.disk;
+ ns.pdsk = mdev->new_state_tmp.pdsk;
+ } else {
+ dev_alert(DEV, "Connection lost while negotiating, no data!\n");
+ ns.disk = D_DISKLESS;
+ ns.pdsk = D_UNKNOWN;
+ }
+ put_ldev(mdev);
+ }
+
+ if (fp == FP_STONITH &&
+ (ns.role == R_PRIMARY &&
+ ns.conn < C_CONNECTED &&
+ ns.pdsk > D_OUTDATED))
+ ns.susp = 1;
+
+ if (ns.aftr_isp || ns.peer_isp || ns.user_isp) {
+ if (ns.conn == C_SYNC_SOURCE)
+ ns.conn = C_PAUSED_SYNC_S;
+ if (ns.conn == C_SYNC_TARGET)
+ ns.conn = C_PAUSED_SYNC_T;
+ } else {
+ if (ns.conn == C_PAUSED_SYNC_S)
+ ns.conn = C_SYNC_SOURCE;
+ if (ns.conn == C_PAUSED_SYNC_T)
+ ns.conn = C_SYNC_TARGET;
+ }
+
+ return ns;
+}
+
+/**
+ * __drbd_set_state() - Set a new DRBD state
+ * @mdev: DRBD device.
+ * @ns: new state.
+ * @flags: Flags
+ * @done: Optional completion, that will get completed after the after_state_ch() finished
+ *
+ * Caller needs to hold req_lock, and global_state_lock. Do not call directly.
+ */
+int __drbd_set_state(struct drbd_conf *mdev,
+ union drbd_state ns, enum chg_state_flags flags,
+ struct completion *done)
+{
+ union drbd_state os;
+ int rv = SS_SUCCESS;
+ int warn_sync_abort = 0;
+ struct after_state_chg_work *ascw;
+
+ os = mdev->state;
+
+ ns = sanitize_state(mdev, os, ns, &warn_sync_abort);
+
+ if (ns.i == os.i)
+ return SS_NOTHING_TO_DO;
+
+ if (!(flags & CS_HARD)) {
+ /* pre-state-change checks ; only look at ns */
+ /* See drbd_state_sw_errors in drbd_strings.c */
+
+ rv = is_valid_state(mdev, ns);
+ if (rv < SS_SUCCESS) {
+ /* If the old state was illegal as well, then let
+ this happen...*/
+
+ if (is_valid_state(mdev, os) == rv) {
+ dev_err(DEV, "Considering state change from bad state. "
+ "Error would be: '%s'\n",
+ set_st_err_name(rv));
+ print_st(mdev, "old", os);
+ print_st(mdev, "new", ns);
+ rv = is_valid_state_transition(mdev, ns, os);
+ }
+ } else
+ rv = is_valid_state_transition(mdev, ns, os);
+ }
+
+ if (rv < SS_SUCCESS) {
+ if (flags & CS_VERBOSE)
+ print_st_err(mdev, os, ns, rv);
+ return rv;
+ }
+
+ if (warn_sync_abort)
+ dev_warn(DEV, "Resync aborted.\n");
+
+ {
+ char *pbp, pb[300];
+ pbp = pb;
+ *pbp = 0;
+ PSC(role);
+ PSC(peer);
+ PSC(conn);
+ PSC(disk);
+ PSC(pdsk);
+ PSC(susp);
+ PSC(aftr_isp);
+ PSC(peer_isp);
+ PSC(user_isp);
+ dev_info(DEV, "%s\n", pb);
+ }
+
+ /* solve the race between becoming unconfigured,
+ * worker doing the cleanup, and
+ * admin reconfiguring us:
+ * on (re)configure, first set CONFIG_PENDING,
+ * then wait for a potentially exiting worker,
+ * start the worker, and schedule one no_op.
+ * then proceed with configuration.
+ */
+ if (ns.disk == D_DISKLESS &&
+ ns.conn == C_STANDALONE &&
+ ns.role == R_SECONDARY &&
+ !test_and_set_bit(CONFIG_PENDING, &mdev->flags))
+ set_bit(DEVICE_DYING, &mdev->flags);
+
+ mdev->state.i = ns.i;
+ wake_up(&mdev->misc_wait);
+ wake_up(&mdev->state_wait);
+
+ /* post-state-change actions */
+ if (os.conn >= C_SYNC_SOURCE && ns.conn <= C_CONNECTED) {
+ set_bit(STOP_SYNC_TIMER, &mdev->flags);
+ mod_timer(&mdev->resync_timer, jiffies);
+ }
+
+ if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) &&
+ (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) {
+ dev_info(DEV, "Syncer continues.\n");
+ mdev->rs_paused += (long)jiffies-(long)mdev->rs_mark_time;
+ if (ns.conn == C_SYNC_TARGET) {
+ if (!test_and_clear_bit(STOP_SYNC_TIMER, &mdev->flags))
+ mod_timer(&mdev->resync_timer, jiffies);
+ /* This if (!test_bit) is only needed for the case
+ that a device that has ceased to used its timer,
+ i.e. it is already in drbd_resync_finished() gets
+ paused and resumed. */
+ }
+ }
+
+ if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) &&
+ (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) {
+ dev_info(DEV, "Resync suspended\n");
+ mdev->rs_mark_time = jiffies;
+ if (ns.conn == C_PAUSED_SYNC_T)
+ set_bit(STOP_SYNC_TIMER, &mdev->flags);
+ }
+
+ if (os.conn == C_CONNECTED &&
+ (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) {
+ mdev->ov_position = 0;
+ mdev->ov_left =
+ mdev->rs_total =
+ mdev->rs_mark_left = drbd_bm_bits(mdev);
+ mdev->rs_start =
+ mdev->rs_mark_time = jiffies;
+ mdev->ov_last_oos_size = 0;
+ mdev->ov_last_oos_start = 0;
+
+ if (ns.conn == C_VERIFY_S)
+ mod_timer(&mdev->resync_timer, jiffies);
+ }
+
+ if (get_ldev(mdev)) {
+ u32 mdf = mdev->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND|
+ MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE|
+ MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY);
+
+ if (test_bit(CRASHED_PRIMARY, &mdev->flags))
+ mdf |= MDF_CRASHED_PRIMARY;
+ if (mdev->state.role == R_PRIMARY ||
+ (mdev->state.pdsk < D_INCONSISTENT && mdev->state.peer == R_PRIMARY))
+ mdf |= MDF_PRIMARY_IND;
+ if (mdev->state.conn > C_WF_REPORT_PARAMS)
+ mdf |= MDF_CONNECTED_IND;
+ if (mdev->state.disk > D_INCONSISTENT)
+ mdf |= MDF_CONSISTENT;
+ if (mdev->state.disk > D_OUTDATED)
+ mdf |= MDF_WAS_UP_TO_DATE;
+ if (mdev->state.pdsk <= D_OUTDATED && mdev->state.pdsk >= D_INCONSISTENT)
+ mdf |= MDF_PEER_OUT_DATED;
+ if (mdf != mdev->ldev->md.flags) {
+ mdev->ldev->md.flags = mdf;
+ drbd_md_mark_dirty(mdev);
+ }
+ if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT)
+ drbd_set_ed_uuid(mdev, mdev->ldev->md.uuid[UI_CURRENT]);
+ put_ldev(mdev);
+ }
+
+ /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */
+ if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT &&
+ os.peer == R_SECONDARY && ns.peer == R_PRIMARY)
+ set_bit(CONSIDER_RESYNC, &mdev->flags);
+
+ /* Receiver should clean up itself */
+ if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING)
+ drbd_thread_stop_nowait(&mdev->receiver);
+
+ /* Now the receiver finished cleaning up itself, it should die */
+ if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE)
+ drbd_thread_stop_nowait(&mdev->receiver);
+
+ /* Upon network failure, we need to restart the receiver. */
+ if (os.conn > C_TEAR_DOWN &&
+ ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT)
+ drbd_thread_restart_nowait(&mdev->receiver);
+
+ ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC);
+ if (ascw) {
+ ascw->os = os;
+ ascw->ns = ns;
+ ascw->flags = flags;
+ ascw->w.cb = w_after_state_ch;
+ ascw->done = done;
+ drbd_queue_work(&mdev->data.work, &ascw->w);
+ } else {
+ dev_warn(DEV, "Could not kmalloc an ascw\n");
+ }
+
+ return rv;
+}
+
+STATIC int w_after_state_ch(struct drbd_conf *mdev, struct drbd_work *w, int unused)
+{
+ struct after_state_chg_work *ascw;
+
+ ascw = (struct after_state_chg_work *) w;
+ after_state_ch(mdev, ascw->os, ascw->ns, ascw->flags);
+ if (ascw->flags & CS_WAIT_COMPLETE) {
+ D_ASSERT(ascw->done != NULL);
+ complete(ascw->done);
+ }
+ kfree(ascw);
+
+ return 1;
+}
+
+static void abw_start_sync(struct drbd_conf *mdev, int rv)
+{
+ if (rv) {
+ dev_err(DEV, "Writing the bitmap failed not starting resync.\n");
+ _drbd_request_state(mdev, NS(conn, C_CONNECTED), CS_VERBOSE);
+ return;
+ }
+
+ switch (mdev->state.conn) {
+ case C_STARTING_SYNC_T:
+ _drbd_request_state(mdev, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
+ break;
+ case C_STARTING_SYNC_S:
+ drbd_start_resync(mdev, C_SYNC_SOURCE);
+ break;
+ }
+}
+
+/**
+ * after_state_ch() - Perform after state change actions that may sleep
+ * @mdev: DRBD device.
+ * @os: old state.
+ * @ns: new state.
+ * @flags: Flags
+ */
+STATIC void after_state_ch(struct drbd_conf *mdev, union drbd_state os,
+ union drbd_state ns, enum chg_state_flags flags)
+{
+ enum drbd_fencing_p fp;
+
+ if (os.conn != C_CONNECTED && ns.conn == C_CONNECTED) {
+ clear_bit(CRASHED_PRIMARY, &mdev->flags);
+ if (mdev->p_uuid)
+ mdev->p_uuid[UI_FLAGS] &= ~((u64)2);
+ }
+
+ fp = FP_DONT_CARE;
+ if (get_ldev(mdev)) {
+ fp = mdev->ldev->dc.fencing;
+ put_ldev(mdev);
+ }
+
+ /* Inform userspace about the change... */
+ drbd_bcast_state(mdev, ns);
+
+ if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) &&
+ (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE))
+ drbd_khelper(mdev, "pri-on-incon-degr");
+
+ /* Here we have the actions that are performed after a
+ state change. This function might sleep */
+
+ if (fp == FP_STONITH && ns.susp) {
+ /* case1: The outdate peer handler is successfull:
+ * case2: The connection was established again: */
+ if ((os.pdsk > D_OUTDATED && ns.pdsk <= D_OUTDATED) ||
+ (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED)) {
+ tl_clear(mdev);
+ spin_lock_irq(&mdev->req_lock);
+ _drbd_set_state(_NS(mdev, susp, 0), CS_VERBOSE, NULL);
+ spin_unlock_irq(&mdev->req_lock);
+ }
+ }
+ /* Do not change the order of the if above and the two below... */
+ if (os.pdsk == D_DISKLESS && ns.pdsk > D_DISKLESS) { /* attach on the peer */
+ drbd_send_uuids(mdev);
+ drbd_send_state(mdev);
+ }
+ if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S)
+ drbd_queue_bitmap_io(mdev, &drbd_send_bitmap, NULL, "send_bitmap (WFBitMapS)");
+
+ /* Lost contact to peer's copy of the data */
+ if ((os.pdsk >= D_INCONSISTENT &&
+ os.pdsk != D_UNKNOWN &&
+ os.pdsk != D_OUTDATED)
+ && (ns.pdsk < D_INCONSISTENT ||
+ ns.pdsk == D_UNKNOWN ||
+ ns.pdsk == D_OUTDATED)) {
+ kfree(mdev->p_uuid);
+ mdev->p_uuid = NULL;
+ if (get_ldev(mdev)) {
+ if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) &&
+ mdev->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) {
+ drbd_uuid_new_current(mdev);
+ drbd_send_uuids(mdev);
+ }
+ put_ldev(mdev);
+ }
+ }
+
+ if (ns.pdsk < D_INCONSISTENT && get_ldev(mdev)) {
+ if (ns.peer == R_PRIMARY && mdev->ldev->md.uuid[UI_BITMAP] == 0)
+ drbd_uuid_new_current(mdev);
+
+ /* D_DISKLESS Peer becomes secondary */
+ if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY)
+ drbd_al_to_on_disk_bm(mdev);
+ put_ldev(mdev);
+ }
+
+ /* Last part of the attaching process ... */
+ if (ns.conn >= C_CONNECTED &&
+ os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) {
+ kfree(mdev->p_uuid); /* We expect to receive up-to-date UUIDs soon. */
+ mdev->p_uuid = NULL; /* ...to not use the old ones in the mean time */
+ drbd_send_sizes(mdev); /* to start sync... */
+ drbd_send_uuids(mdev);
+ drbd_send_state(mdev);
+ }
+
+ /* We want to pause/continue resync, tell peer. */
+ if (ns.conn >= C_CONNECTED &&
+ ((os.aftr_isp != ns.aftr_isp) ||
+ (os.user_isp != ns.user_isp)))
+ drbd_send_state(mdev);
+
+ /* In case one of the isp bits got set, suspend other devices. */
+ if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) &&
+ (ns.aftr_isp || ns.peer_isp || ns.user_isp))
+ suspend_other_sg(mdev);
+
+ /* Make sure the peer gets informed about eventual state
+ changes (ISP bits) while we were in WFReportParams. */
+ if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED)
+ drbd_send_state(mdev);
+
+ /* We are in the progress to start a full sync... */
+ if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) ||
+ (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S))
+ drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, &abw_start_sync, "set_n_write from StartingSync");
+
+ /* We are invalidating our self... */
+ if (os.conn < C_CONNECTED && ns.conn < C_CONNECTED &&
+ os.disk > D_INCONSISTENT && ns.disk == D_INCONSISTENT)
+ drbd_queue_bitmap_io(mdev, &drbd_bmio_set_n_write, NULL, "set_n_write from invalidate");
+
+ if (os.disk > D_DISKLESS && ns.disk == D_DISKLESS) {
+ /* since get_ldev() only works as long as disk>=D_INCONSISTENT,
+ and it is D_DISKLESS here, local_cnt can only go down, it can
+ not increase... It will reach zero */
+ wait_event(mdev->misc_wait, !atomic_read(&mdev->local_cnt));
+
+ drbd_rs_cancel_all(mdev);
+ mdev->rs_total = 0;
+ mdev->rs_failed = 0;
+ atomic_set(&mdev->rs_pending_cnt, 0);
+
+ lc_destroy(mdev->resync);
+ mdev->resync = NULL;
+ lc_destroy(mdev->act_log);
+ mdev->act_log = NULL;
+ __no_warn(local,
+ drbd_free_bc(mdev->ldev);
+ mdev->ldev = NULL;);
+
+ if (mdev->md_io_tmpp)
+ __free_page(mdev->md_io_tmpp);
+ }
+
+ /* Disks got bigger while they were detached */
+ if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING &&
+ test_and_clear_bit(RESYNC_AFTER_NEG, &mdev->flags)) {
+ if (ns.conn == C_CONNECTED)
+ resync_after_online_grow(mdev);
+ }
+
+ /* A resync finished or aborted, wake paused devices... */
+ if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) ||
+ (os.peer_isp && !ns.peer_isp) ||
+ (os.user_isp && !ns.user_isp))
+ resume_next_sg(mdev);
+
+ /* Upon network connection, we need to start the received */
+ if (os.conn == C_STANDALONE && ns.conn == C_UNCONNECTED)
+ drbd_thread_start(&mdev->receiver);
+
+ /* Terminate worker thread if we are unconfigured - it will be
+ restarted as needed... */
+ if (ns.disk == D_DISKLESS &&
+ ns.conn == C_STANDALONE &&
+ ns.role == R_SECONDARY) {
+ if (os.aftr_isp != ns.aftr_isp)
+ resume_next_sg(mdev);
+ /* set in __drbd_set_state, unless CONFIG_PENDING was set */
+ if (test_bit(DEVICE_DYING, &mdev->flags))
+ drbd_thread_stop_nowait(&mdev->worker);
+ }
+
+ drbd_md_sync(mdev);
+}
+
+
+STATIC int drbd_thread_setup(void *arg)
+{
+ struct drbd_thread *thi = (struct drbd_thread *) arg;
+ struct drbd_conf *mdev = thi->mdev;
+ unsigned long flags;
+ int retval;
+
+restart:
+ retval = thi->function(thi);
+
+ spin_lock_irqsave(&thi->t_lock, flags);
+
+ /* if the receiver has been "Exiting", the last thing it did
+ * was set the conn state to "StandAlone",
+ * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
+ * and receiver thread will be "started".
+ * drbd_thread_start needs to set "Restarting" in that case.
+ * t_state check and assignement needs to be within the same spinlock,
+ * so either thread_start sees Exiting, and can remap to Restarting,
+ * or thread_start see None, and can proceed as normal.
+ */
+
+ if (thi->t_state == Restarting) {
+ dev_info(DEV, "Restarting %s\n", current->comm);
+ thi->t_state = Running;
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ goto restart;
+ }
+
+ thi->task = NULL;
+ thi->t_state = None;
+ smp_mb();
+ complete(&thi->stop);
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+
+ dev_info(DEV, "Terminating %s\n", current->comm);
+
+ /* Release mod reference taken when thread was started */
+ module_put(THIS_MODULE);
+ return retval;
+}
+
+STATIC void drbd_thread_init(struct drbd_conf *mdev, struct drbd_thread *thi,
+ int (*func) (struct drbd_thread *))
+{
+ spin_lock_init(&thi->t_lock);
+ thi->task = NULL;
+ thi->t_state = None;
+ thi->function = func;
+ thi->mdev = mdev;
+}
+
+int drbd_thread_start(struct drbd_thread *thi)
+{
+ struct drbd_conf *mdev = thi->mdev;
+ struct task_struct *nt;
+ unsigned long flags;
+
+ const char *me =
+ thi == &mdev->receiver ? "receiver" :
+ thi == &mdev->asender ? "asender" :
+ thi == &mdev->worker ? "worker" : "NONSENSE";
+
+ /* is used from state engine doing drbd_thread_stop_nowait,
+ * while holding the req lock irqsave */
+ spin_lock_irqsave(&thi->t_lock, flags);
+
+ switch (thi->t_state) {
+ case None:
+ dev_info(DEV, "Starting %s thread (from %s [%d])\n",
+ me, current->comm, current->pid);
+
+ /* Get ref on module for thread - this is released when thread exits */
+ if (!try_module_get(THIS_MODULE)) {
+ dev_err(DEV, "Failed to get module reference in drbd_thread_start\n");
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ return FALSE;
+ }
+
+ D_ASSERT(thi->task == NULL);
+ thi->reset_cpu_mask = 1;
+ thi->t_state = Running;
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ flush_signals(current); /* otherw. may get -ERESTARTNOINTR */
+
+ nt = kthread_create(drbd_thread_setup, (void *) thi,
+ "drbd%d_%s", mdev_to_minor(mdev), me);
+
+ if (IS_ERR(nt)) {
+ dev_err(DEV, "Couldn't start thread\n");
+
+ module_put(THIS_MODULE);
+ return FALSE;
+ }
+ spin_lock(&thi->t_lock);
+ thi->task = nt;
+ thi->t_state = Running;
+ spin_unlock(&thi->t_lock);
+ wake_up_process(nt);
+ break;
+ case Exiting:
+ thi->t_state = Restarting;
+ dev_info(DEV, "Restarting %s thread (from %s [%d])\n",
+ me, current->comm, current->pid);
+ /* fall through */
+ case Running:
+ case Restarting:
+ default:
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ break;
+ }
+
+ return TRUE;
+}
+
+
+void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
+{
+ unsigned long flags;
+ enum drbd_thread_state ns = restart ? Restarting : Exiting;
+
+ /* may be called from state engine, holding the req lock irqsave */
+ spin_lock_irqsave(&thi->t_lock, flags);
+
+ if (thi->t_state == None) {
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ if (restart)
+ drbd_thread_start(thi);
+ return;
+ }
+
+ if (thi->t_state != ns) {
+ if (thi->task == NULL) {
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+ return;
+ }
+
+ thi->t_state = ns;
+ smp_mb();
+ init_completion(&thi->stop);
+ if (thi->task != current)
+ force_sig(DRBD_SIGKILL, thi->task);
+
+ }
+
+ spin_unlock_irqrestore(&thi->t_lock, flags);
+
+ if (wait)
+ wait_for_completion(&thi->stop);
+}
+
+#ifdef CONFIG_SMP
+/**
+ * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
+ * @mdev: DRBD device.
+ *
+ * Forces all threads of a device onto the same CPU. This is benificial for
+ * DRBD's performance. May be overwritten by user's configuration.
+ */
+cpumask_t drbd_calc_cpu_mask(struct drbd_conf *mdev)
+{
+ int sv, cpu;
+ cpumask_t av_cpu_m;
+
+ if (cpus_weight(mdev->cpu_mask))
+ return mdev->cpu_mask;
+
+ av_cpu_m = cpu_online_map;
+ sv = mdev_to_minor(mdev) % cpus_weight(av_cpu_m);
+
+ for_each_cpu_mask(cpu, av_cpu_m) {
+ if (sv-- == 0)
+ return cpumask_of_cpu(cpu);
+ }
+
+ /* some kernel versions "forget" to add the (cpumask_t) typecast
+ * to that macro, which results in "parse error before '{'" ;-> */
+ return (cpumask_t) CPU_MASK_ALL; /* Never reached. */
+}
+
+/**
+ * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
+ * @mdev: DRBD device.
+ *
+ * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
+ * prematurely.
+ */
+void drbd_thread_current_set_cpu(struct drbd_conf *mdev)
+{
+ struct task_struct *p = current;
+ struct drbd_thread *thi =
+ p == mdev->asender.task ? &mdev->asender :
+ p == mdev->receiver.task ? &mdev->receiver :
+ p == mdev->worker.task ? &mdev->worker :
+ NULL;
+ ERR_IF(thi == NULL)
+ return;
+ if (!thi->reset_cpu_mask)
+ return;
+ thi->reset_cpu_mask = 0;
+ /* preempt_disable();
+ Thas was a kernel that warned about a call to smp_processor_id() while preemt
+ was not disabled. It seems that this was fixed in manline. */
+ set_cpus_allowed(p, mdev->cpu_mask);
+ /* preempt_enable(); */
+}
+#endif
+
+/* the appropriate socket mutex must be held already */
+int _drbd_send_cmd(struct drbd_conf *mdev, struct socket *sock,
+ enum drbd_packets cmd, struct p_header *h,
+ size_t size, unsigned msg_flags)
+{
+ int sent, ok;
+
+ ERR_IF(!h) return FALSE;
+ ERR_IF(!size) return FALSE;
+
+ h->magic = BE_DRBD_MAGIC;
+ h->command = cpu_to_be16(cmd);
+ h->length = cpu_to_be16(size-sizeof(struct p_header));
+
+ trace_drbd_packet(mdev, sock, 0, (void *)h, __FILE__, __LINE__);
+ sent = drbd_send(mdev, sock, h, size, msg_flags);
+
+ ok = (sent == size);
+ if (!ok)
+ dev_err(DEV, "short sent %s size=%d sent=%d\n",
+ cmdname(cmd), (int)size, sent);
+ return ok;
+}
+
+/* don't pass the socket. we may only look at it
+ * when we hold the appropriate socket mutex.
+ */
+int drbd_send_cmd(struct drbd_conf *mdev, int use_data_socket,
+ enum drbd_packets cmd, struct p_header *h, size_t size)
+{
+ int ok = 0;
+ struct socket *sock;
+
+ if (use_data_socket) {
+ mutex_lock(&mdev->data.mutex);
+ sock = mdev->data.socket;
+ } else {
+ mutex_lock(&mdev->meta.mutex);
+ sock = mdev->meta.socket;
+ }
+
+ /* drbd_disconnect() could have called drbd_free_sock()
+ * while we were waiting in down()... */
+ if (likely(sock != NULL))
+ ok = _drbd_send_cmd(mdev, sock, cmd, h, size, 0);
+
+ if (use_data_socket)
+ mutex_unlock(&mdev->data.mutex);
+ else
+ mutex_unlock(&mdev->meta.mutex);
+ return ok;
+}
+
+int drbd_send_cmd2(struct drbd_conf *mdev, enum drbd_packets cmd, char *data,
+ size_t size)
+{
+ struct p_header h;
+ int ok;
+
+ h.magic = BE_DRBD_MAGIC;
+ h.command = cpu_to_be16(cmd);
+ h.length = cpu_to_be16(size);
+
+ if (!drbd_get_data_sock(mdev))
+ return 0;
+
+ trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&h, __FILE__, __LINE__);
+
+ ok = (sizeof(h) ==
+ drbd_send(mdev, mdev->data.socket, &h, sizeof(h), 0));
+ ok = ok && (size ==
+ drbd_send(mdev, mdev->data.socket, data, size, 0));
+
+ drbd_put_data_sock(mdev);
+
+ return ok;
+}
+
+int drbd_send_sync_param(struct drbd_conf *mdev, struct syncer_conf *sc)
+{
+ struct p_rs_param_89 *p;
+ struct socket *sock;
+ int size, rv;
+ const int apv = mdev->agreed_pro_version;
+
+ size = apv <= 87 ? sizeof(struct p_rs_param)
+ : apv == 88 ? sizeof(struct p_rs_param)
+ + strlen(mdev->sync_conf.verify_alg) + 1
+ : /* 89 */ sizeof(struct p_rs_param_89);
+
+ /* used from admin command context and receiver/worker context.
+ * to avoid kmalloc, grab the socket right here,
+ * then use the pre-allocated sbuf there */
+ mutex_lock(&mdev->data.mutex);
+ sock = mdev->data.socket;
+
+ if (likely(sock != NULL)) {
+ enum drbd_packets cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
+
+ p = &mdev->data.sbuf.rs_param_89;
+
+ /* initialize verify_alg and csums_alg */
+ memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
+
+ p->rate = cpu_to_be32(sc->rate);
+
+ if (apv >= 88)
+ strcpy(p->verify_alg, mdev->sync_conf.verify_alg);
+ if (apv >= 89)
+ strcpy(p->csums_alg, mdev->sync_conf.csums_alg);
+
+ rv = _drbd_send_cmd(mdev, sock, cmd, &p->head, size, 0);
+ } else
+ rv = 0; /* not ok */
+
+ mutex_unlock(&mdev->data.mutex);
+
+ return rv;
+}
+
+int drbd_send_protocol(struct drbd_conf *mdev)
+{
+ struct p_protocol *p;
+ int size, rv;
+
+ size = sizeof(struct p_protocol);
+
+ if (mdev->agreed_pro_version >= 87)
+ size += strlen(mdev->net_conf->integrity_alg) + 1;
+
+ p = kmalloc(size, GFP_KERNEL);
+ if (p == NULL)
+ return 0;
+
+ p->protocol = cpu_to_be32(mdev->net_conf->wire_protocol);
+ p->after_sb_0p = cpu_to_be32(mdev->net_conf->after_sb_0p);
+ p->after_sb_1p = cpu_to_be32(mdev->net_conf->after_sb_1p);
+ p->after_sb_2p = cpu_to_be32(mdev->net_conf->after_sb_2p);
+ p->want_lose = cpu_to_be32(mdev->net_conf->want_lose);
+ p->two_primaries = cpu_to_be32(mdev->net_conf->two_primaries);
+
+ if (mdev->agreed_pro_version >= 87)
+ strcpy(p->integrity_alg, mdev->net_conf->integrity_alg);
+
+ rv = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_PROTOCOL,
+ (struct p_header *)p, size);
+ kfree(p);
+ return rv;
+}
+
+int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
+{
+ struct p_uuids p;
+ int i;
+
+ if (!get_ldev_if_state(mdev, D_NEGOTIATING))
+ return 1;
+
+ for (i = UI_CURRENT; i < UI_SIZE; i++)
+ p.uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
+
+ mdev->comm_bm_set = drbd_bm_total_weight(mdev);
+ p.uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
+ uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
+ uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
+ uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
+ p.uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
+
+ put_ldev(mdev);
+
+ return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_UUIDS,
+ (struct p_header *)&p, sizeof(p));
+}
+
+int drbd_send_uuids(struct drbd_conf *mdev)
+{
+ return _drbd_send_uuids(mdev, 0);
+}
+
+int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
+{
+ return _drbd_send_uuids(mdev, 8);
+}
+
+
+int drbd_send_sync_uuid(struct drbd_conf *mdev, u64 val)
+{
+ struct p_rs_uuid p;
+
+ p.uuid = cpu_to_be64(val);
+
+ return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SYNC_UUID,
+ (struct p_header *)&p, sizeof(p));
+}
+
+int drbd_send_sizes(struct drbd_conf *mdev)
+{
+ struct p_sizes p;
+ sector_t d_size, u_size;
+ int q_order_type;
+ int ok;
+
+ if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
+ D_ASSERT(mdev->ldev->backing_bdev);
+ d_size = drbd_get_max_capacity(mdev->ldev);
+ u_size = mdev->ldev->dc.disk_size;
+ q_order_type = drbd_queue_order_type(mdev);
+ p.queue_order_type = cpu_to_be32(drbd_queue_order_type(mdev));
+ put_ldev(mdev);
+ } else {
+ d_size = 0;
+ u_size = 0;
+ q_order_type = QUEUE_ORDERED_NONE;
+ }
+
+ p.d_size = cpu_to_be64(d_size);
+ p.u_size = cpu_to_be64(u_size);
+ p.c_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
+ p.max_segment_size = cpu_to_be32(mdev->rq_queue->max_segment_size);
+ p.queue_order_type = cpu_to_be32(q_order_type);
+
+ ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_SIZES,
+ (struct p_header *)&p, sizeof(p));
+ return ok;
+}
+
+/**
+ * drbd_send_state() - Sends the drbd state to the peer
+ * @mdev: DRBD device.
+ */
+int drbd_send_state(struct drbd_conf *mdev)
+{
+ struct socket *sock;
+ struct p_state p;
+ int ok = 0;
+
+ /* Grab state lock so we wont send state if we're in the middle
+ * of a cluster wide state change on another thread */
+ drbd_state_lock(mdev);
+
+ mutex_lock(&mdev->data.mutex);
+
+ p.state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
+ sock = mdev->data.socket;
+
+ if (likely(sock != NULL)) {
+ ok = _drbd_send_cmd(mdev, sock, P_STATE,
+ (struct p_header *)&p, sizeof(p), 0);
+ }
+
+ mutex_unlock(&mdev->data.mutex);
+
+ drbd_state_unlock(mdev);
+ return ok;
+}
+
+int drbd_send_state_req(struct drbd_conf *mdev,
+ union drbd_state mask, union drbd_state val)
+{
+ struct p_req_state p;
+
+ p.mask = cpu_to_be32(mask.i);
+ p.val = cpu_to_be32(val.i);
+
+ return drbd_send_cmd(mdev, USE_DATA_SOCKET, P_STATE_CHG_REQ,
+ (struct p_header *)&p, sizeof(p));
+}
+
+int drbd_send_sr_reply(struct drbd_conf *mdev, int retcode)
+{
+ struct p_req_state_reply p;
+
+ p.retcode = cpu_to_be32(retcode);
+
+ return drbd_send_cmd(mdev, USE_META_SOCKET, P_STATE_CHG_REPLY,
+ (struct p_header *)&p, sizeof(p));
+}
+
+int fill_bitmap_rle_bits(struct drbd_conf *mdev,
+ struct p_compressed_bm *p,
+ struct bm_xfer_ctx *c)
+{
+ struct bitstream bs;
+ unsigned long plain_bits;
+ unsigned long tmp;
+ unsigned long rl;
+ unsigned len;
+ unsigned toggle;
+ int bits;
+
+ /* may we use this feature? */
+ if ((mdev->sync_conf.use_rle_encoding == 0) ||
+ (mdev->agreed_pro_version < 90))
+ return 0;
+
+ if (c->bit_offset >= c->bm_bits)
+ return 0; /* nothing to do. */
+
+ /* use at most thus many bytes */
+ bitstream_init(&bs, p->code, BM_PACKET_VLI_BYTES_MAX, 0);
+ memset(p->code, 0, BM_PACKET_VLI_BYTES_MAX);
+ /* plain bits covered in this code string */
+ plain_bits = 0;
+
+ /* p->encoding & 0x80 stores whether the first run length is set.
+ * bit offset is implicit.
+ * start with toggle == 2 to be able to tell the first iteration */
+ toggle = 2;
+
+ /* see how much plain bits we can stuff into one packet
+ * using RLE and VLI. */
+ do {
+ tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
+ : _drbd_bm_find_next(mdev, c->bit_offset);
+ if (tmp == -1UL)
+ tmp = c->bm_bits;
+ rl = tmp - c->bit_offset;
+
+ if (toggle == 2) { /* first iteration */
+ if (rl == 0) {
+ /* the first checked bit was set,
+ * store start value, */
+ DCBP_set_start(p, 1);
+ /* but skip encoding of zero run length */
+ toggle = !toggle;
+ continue;
+ }
+ DCBP_set_start(p, 0);
+ }
+
+ /* paranoia: catch zero runlength.
+ * can only happen if bitmap is modified while we scan it. */
+ if (rl == 0) {
+ dev_err(DEV, "unexpected zero runlength while encoding bitmap "
+ "t:%u bo:%lu\n", toggle, c->bit_offset);
+ return -1;
+ }
+
+ bits = vli_encode_bits(&bs, rl);
+ if (bits == -ENOBUFS) /* buffer full */
+ break;
+ if (bits <= 0) {
+ dev_err(DEV, "error while encoding bitmap: %d\n", bits);
+ return 0;
+ }
+
+ toggle = !toggle;
+ plain_bits += rl;
+ c->bit_offset = tmp;
+ } while (c->bit_offset < c->bm_bits);
+
+ len = bs.cur.b - p->code + !!bs.cur.bit;
+
+ if (plain_bits < (len << 3)) {
+ /* incompressible with this method.
+ * we need to rewind both word and bit position. */
+ c->bit_offset -= plain_bits;
+ bm_xfer_ctx_bit_to_word_offset(c);
+ c->bit_offset = c->word_offset * BITS_PER_LONG;
+ return 0;
+ }
+
+ /* RLE + VLI was able to compress it just fine.
+ * update c->word_offset. */
+ bm_xfer_ctx_bit_to_word_offset(c);
+
+ /* store pad_bits */
+ DCBP_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
+
+ return len;
+}
+
+enum { OK, FAILED, DONE }
+send_bitmap_rle_or_plain(struct drbd_conf *mdev,
+ struct p_header *h, struct bm_xfer_ctx *c)
+{
+ struct p_compressed_bm *p = (void*)h;
+ unsigned long num_words;
+ int len;
+ int ok;
+
+ len = fill_bitmap_rle_bits(mdev, p, c);
+
+ if (len < 0)
+ return FAILED;
+
+ if (len) {
+ DCBP_set_code(p, RLE_VLI_Bits);
+ ok = _drbd_send_cmd(mdev, mdev->data.socket, P_COMPRESSED_BITMAP, h,
+ sizeof(*p) + len, 0);
+
+ c->packets[0]++;
+ c->bytes[0] += sizeof(*p) + len;
+
+ if (c->bit_offset >= c->bm_bits)
+ len = 0; /* DONE */
+ } else {
+ /* was not compressible.
+ * send a buffer full of plain text bits instead. */
+ num_words = min_t(size_t, BM_PACKET_WORDS, c->bm_words - c->word_offset);
+ len = num_words * sizeof(long);
+ if (len)
+ drbd_bm_get_lel(mdev, c->word_offset, num_words, (unsigned long*)h->payload);
+ ok = _drbd_send_cmd(mdev, mdev->data.socket, P_BITMAP,
+ h, sizeof(struct p_header) + len, 0);
+ c->word_offset += num_words;
+ c->bit_offset = c->word_offset * BITS_PER_LONG;
+
+ c->packets[1]++;
+ c->bytes[1] += sizeof(struct p_header) + len;
+
+ if (c->bit_offset > c->bm_bits)
+ c->bit_offset = c->bm_bits;
+ }
+ ok = ok ? ((len == 0) ? DONE : OK) : FAILED;
+
+ if (ok == DONE)
+ INFO_bm_xfer_stats(mdev, "send", c);
+ return ok;
+}
+
+/* See the comment at receive_bitmap() */
+int _drbd_send_bitmap(struct drbd_conf *mdev)
+{
+ struct bm_xfer_ctx c;
+ struct p_header *p;
+ int ret;
+
+ ERR_IF(!mdev->bitmap) return FALSE;
+
+ /* maybe we should use some per thread scratch page,
+ * and allocate that during initial device creation? */
+ p = (struct p_header *) __get_free_page(GFP_NOIO);
+ if (!p) {
+ dev_err(DEV, "failed to allocate one page buffer in %s\n", __func__);
+ return FALSE;
+ }
+
+ if (get_ldev(mdev)) {
+ if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
+ dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
+ drbd_bm_set_all(mdev);
+ if (drbd_bm_write(mdev)) {
+ /* write_bm did fail! Leave full sync flag set in Meta P_DATA
+ * but otherwise process as per normal - need to tell other
+ * side that a full resync is required! */
+ dev_err(DEV, "Failed to write bitmap to disk!\n");
+ } else {
+ drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
+ drbd_md_sync(mdev);
+ }
+ }
+ put_ldev(mdev);
+ }
+
+ c = (struct bm_xfer_ctx) {
+ .bm_bits = drbd_bm_bits(mdev),
+ .bm_words = drbd_bm_words(mdev),
+ };
+
+ do {
+ ret = send_bitmap_rle_or_plain(mdev, p, &c);
+ } while (ret == OK);
+
+ free_page((unsigned long) p);
+ return (ret == DONE);
+}
+
+int drbd_send_bitmap(struct drbd_conf *mdev)
+{
+ int err;
+
+ if (!drbd_get_data_sock(mdev))
+ return -1;
+ err = !_drbd_send_bitmap(mdev);
+ drbd_put_data_sock(mdev);
+ return err;
+}
+
+int drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
+{
+ int ok;
+ struct p_barrier_ack p;
+
+ p.barrier = barrier_nr;
+ p.set_size = cpu_to_be32(set_size);
+
+ if (mdev->state.conn < C_CONNECTED)
+ return FALSE;
+ ok = drbd_send_cmd(mdev, USE_META_SOCKET, P_BARRIER_ACK,
+ (struct p_header *)&p, sizeof(p));
+ return ok;
+}
+
+/**
+ * _drbd_send_ack() - Sends an ack packet
+ * @mdev: DRBD device.
+ * @cmd: Packet command code.
+ * @sector: sector, needs to be in big endian byte order
+ * @blksize: size in byte, needs to be in big endian byte order
+ * @block_id: Id, big endian byte order
+ */
+STATIC int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packets cmd,
+ u64 sector,
+ u32 blksize,
+ u64 block_id)
+{
+ int ok;
+ struct p_block_ack p;
+
+ p.sector = sector;
+ p.block_id = block_id;
+ p.blksize = blksize;
+ p.seq_num = cpu_to_be32(atomic_add_return(1, &mdev->packet_seq));
+
+ if (!mdev->meta.socket || mdev->state.conn < C_CONNECTED)
+ return FALSE;
+ ok = drbd_send_cmd(mdev, USE_META_SOCKET, cmd,
+ (struct p_header *)&p, sizeof(p));
+ return ok;
+}
+
+int drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packets cmd,
+ struct p_data *dp)
+{
+ const int header_size = sizeof(struct p_data)
+ - sizeof(struct p_header);
+ int data_size = ((struct p_header *)dp)->length - header_size;
+
+ return _drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
+ dp->block_id);
+}
+
+int drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packets cmd,
+ struct p_block_req *rp)
+{
+ return _drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
+}
+
+/**
+ * drbd_send_ack() - Sends an ack packet
+ * @mdev: DRBD device.
+ * @cmd: Packet command code.
+ * @e: Epoch entry.
+ */
+int drbd_send_ack(struct drbd_conf *mdev,
+ enum drbd_packets cmd, struct drbd_epoch_entry *e)
+{
+ return _drbd_send_ack(mdev, cmd,
+ cpu_to_be64(e->sector),
+ cpu_to_be32(e->size),
+ e->block_id);
+}
+
+/* This function misuses the block_id field to signal if the blocks
+ * are is sync or not. */
+int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packets cmd,
+ sector_t sector, int blksize, u64 block_id)
+{
+ return _drbd_send_ack(mdev, cmd,
+ cpu_to_be64(sector),
+ cpu_to_be32(blksize),
+ cpu_to_be64(block_id));
+}
+
+int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
+ sector_t sector, int size, u64 block_id)
+{
+ int ok;
+ struct p_block_req p;
+
+ p.sector = cpu_to_be64(sector);
+ p.block_id = block_id;
+ p.blksize = cpu_to_be32(size);
+
+ ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, cmd,
+ (struct p_header *)&p, sizeof(p));
+ return ok;
+}
+
+int drbd_send_drequest_csum(struct drbd_conf *mdev,
+ sector_t sector, int size,
+ void *digest, int digest_size,
+ enum drbd_packets cmd)
+{
+ int ok;
+ struct p_block_req p;
+
+ p.sector = cpu_to_be64(sector);
+ p.block_id = BE_DRBD_MAGIC + 0xbeef;
+ p.blksize = cpu_to_be32(size);
+
+ p.head.magic = BE_DRBD_MAGIC;
+ p.head.command = cpu_to_be16(cmd);
+ p.head.length = cpu_to_be16(sizeof(p) - sizeof(struct p_header) + digest_size);
+
+ mutex_lock(&mdev->data.mutex);
+
+ ok = (sizeof(p) == drbd_send(mdev, mdev->data.socket, &p, sizeof(p), 0));
+ ok = ok && (digest_size == drbd_send(mdev, mdev->data.socket, digest, digest_size, 0));
+
+ mutex_unlock(&mdev->data.mutex);
+
+ return ok;
+}
+
+int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
+{
+ int ok;
+ struct p_block_req p;
+
+ p.sector = cpu_to_be64(sector);
+ p.block_id = BE_DRBD_MAGIC + 0xbabe;
+ p.blksize = cpu_to_be32(size);
+
+ ok = drbd_send_cmd(mdev, USE_DATA_SOCKET, P_OV_REQUEST,
+ (struct p_header *)&p, sizeof(p));
+ return ok;
+}
+
+/* called on sndtimeo
+ * returns FALSE if we should retry,
+ * TRUE if we think connection is dead
+ */
+STATIC int we_should_drop_the_connection(struct drbd_conf *mdev, struct socket *sock)
+{
+ int drop_it;
+ /* long elapsed = (long)(jiffies - mdev->last_received); */
+
+ drop_it = mdev->meta.socket == sock
+ || !mdev->asender.task
+ || get_t_state(&mdev->asender) != Running
+ || mdev->state.conn < C_CONNECTED;
+
+ if (drop_it)
+ return TRUE;
+
+ drop_it = !--mdev->ko_count;
+ if (!drop_it) {
+ dev_err(DEV, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
+ current->comm, current->pid, mdev->ko_count);
+ request_ping(mdev);
+ }
+
+ return drop_it; /* && (mdev->state == R_PRIMARY) */;
+}
+
+/* The idea of sendpage seems to be to put some kind of reference
+ * to the page into the skb, and to hand it over to the NIC. In
+ * this process get_page() gets called.
+ *
+ * As soon as the page was really sent over the network put_page()
+ * gets called by some part of the network layer. [ NIC driver? ]
+ *
+ * [ get_page() / put_page() increment/decrement the count. If count
+ * reaches 0 the page will be freed. ]
+ *
+ * This works nicely with pages from FSs.
+ * But this means that in protocol A we might signal IO completion too early!
+ *
+ * In order not to corrupt data during a resync we must make sure
+ * that we do not reuse our own buffer pages (EEs) to early, therefore
+ * we have the net_ee list.
+ *
+ * XFS seems to have problems, still, it submits pages with page_count == 0!
+ * As a workaround, we disable sendpage on pages
+ * with page_count == 0 or PageSlab.
+ */
+STATIC int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
+ int offset, size_t size)
+{
+ int sent = drbd_send(mdev, mdev->data.socket, kmap(page) + offset, size, 0);
+ kunmap(page);
+ if (sent == size)
+ mdev->send_cnt += size>>9;
+ return sent == size;
+}
+
+int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
+ int offset, size_t size)
+{
+ mm_segment_t oldfs = get_fs();
+ int sent, ok;
+ int len = size;
+
+ /* e.g. XFS meta- & log-data is in slab pages, which have a
+ * page_count of 0 and/or have PageSlab() set.
+ * we cannot use send_page for those, as that does get_page();
+ * put_page(); and would cause either a VM_BUG directly, or
+ * __page_cache_release a page that would actually still be referenced
+ * by someone, leading to some obscure delayed Oops somewhere else. */
+ if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
+ return _drbd_no_send_page(mdev, page, offset, size);
+
+ drbd_update_congested(mdev);
+ set_fs(KERNEL_DS);
+ do {
+ sent = mdev->data.socket->ops->sendpage(mdev->data.socket, page,
+ offset, len,
+ MSG_NOSIGNAL);
+ if (sent == -EAGAIN) {
+ if (we_should_drop_the_connection(mdev,
+ mdev->data.socket))
+ break;
+ else
+ continue;
+ }
+ if (sent <= 0) {
+ dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
+ __func__, (int)size, len, sent);
+ break;
+ }
+ len -= sent;
+ offset += sent;
+ } while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
+ set_fs(oldfs);
+ clear_bit(NET_CONGESTED, &mdev->flags);
+
+ ok = (len == 0);
+ if (likely(ok))
+ mdev->send_cnt += size>>9;
+ return ok;
+}
+
+static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
+{
+ struct bio_vec *bvec;
+ int i;
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ if (!_drbd_no_send_page(mdev, bvec->bv_page,
+ bvec->bv_offset, bvec->bv_len))
+ return 0;
+ }
+ return 1;
+}
+
+static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
+{
+ struct bio_vec *bvec;
+ int i;
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ if (!_drbd_send_page(mdev, bvec->bv_page,
+ bvec->bv_offset, bvec->bv_len))
+ return 0;
+ }
+
+ return 1;
+}
+
+/* Used to send write requests
+ * R_PRIMARY -> Peer (P_DATA)
+ */
+int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
+{
+ int ok = 1;
+ struct p_data p;
+ unsigned int dp_flags = 0;
+ void *dgb;
+ int dgs;
+
+ if (!drbd_get_data_sock(mdev))
+ return 0;
+
+ dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
+ crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
+
+ p.head.magic = BE_DRBD_MAGIC;
+ p.head.command = cpu_to_be16(P_DATA);
+ p.head.length =
+ cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + req->size);
+
+ p.sector = cpu_to_be64(req->sector);
+ p.block_id = (unsigned long)req;
+ p.seq_num = cpu_to_be32(req->seq_num =
+ atomic_add_return(1, &mdev->packet_seq));
+ dp_flags = 0;
+
+ /* NOTE: no need to check if barriers supported here as we would
+ * not pass the test in make_request_common in that case
+ */
+ if (bio_barrier(req->master_bio))
+ dp_flags |= DP_HARDBARRIER;
+ if (bio_sync(req->master_bio))
+ dp_flags |= DP_RW_SYNC;
+ if (mdev->state.conn >= C_SYNC_SOURCE &&
+ mdev->state.conn <= C_PAUSED_SYNC_T)
+ dp_flags |= DP_MAY_SET_IN_SYNC;
+
+ p.dp_flags = cpu_to_be32(dp_flags);
+ trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&p, __FILE__, __LINE__);
+ set_bit(UNPLUG_REMOTE, &mdev->flags);
+ ok = (sizeof(p) ==
+ drbd_send(mdev, mdev->data.socket, &p, sizeof(p), MSG_MORE));
+ if (ok && dgs) {
+ dgb = mdev->int_dig_out;
+ drbd_csum(mdev, mdev->integrity_w_tfm, req->master_bio, dgb);
+ ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
+ }
+ if (ok) {
+ if (mdev->net_conf->wire_protocol == DRBD_PROT_A)
+ ok = _drbd_send_bio(mdev, req->master_bio);
+ else
+ ok = _drbd_send_zc_bio(mdev, req->master_bio);
+ }
+
+ drbd_put_data_sock(mdev);
+ return ok;
+}
+
+/* answer packet, used to send data back for read requests:
+ * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY)
+ * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY)
+ */
+int drbd_send_block(struct drbd_conf *mdev, enum drbd_packets cmd,
+ struct drbd_epoch_entry *e)
+{
+ int ok;
+ struct p_data p;
+ void *dgb;
+ int dgs;
+
+ dgs = (mdev->agreed_pro_version >= 87 && mdev->integrity_w_tfm) ?
+ crypto_hash_digestsize(mdev->integrity_w_tfm) : 0;
+
+ p.head.magic = BE_DRBD_MAGIC;
+ p.head.command = cpu_to_be16(cmd);
+ p.head.length =
+ cpu_to_be16(sizeof(p) - sizeof(struct p_header) + dgs + e->size);
+
+ p.sector = cpu_to_be64(e->sector);
+ p.block_id = e->block_id;
+ /* p.seq_num = 0; No sequence numbers here.. */
+
+ /* Only called by our kernel thread.
+ * This one may be interupted by DRBD_SIG and/or DRBD_SIGKILL
+ * in response to admin command or module unload.
+ */
+ if (!drbd_get_data_sock(mdev))
+ return 0;
+
+ trace_drbd_packet(mdev, mdev->data.socket, 0, (void *)&p, __FILE__, __LINE__);
+ ok = sizeof(p) == drbd_send(mdev, mdev->data.socket, &p,
+ sizeof(p), MSG_MORE);
+ if (ok && dgs) {
+ dgb = mdev->int_dig_out;
+ drbd_csum(mdev, mdev->integrity_w_tfm, e->private_bio, dgb);
+ ok = drbd_send(mdev, mdev->data.socket, dgb, dgs, MSG_MORE);
+ }
+ if (ok)
+ ok = _drbd_send_zc_bio(mdev, e->private_bio);
+
+ drbd_put_data_sock(mdev);
+ return ok;
+}
+
+/*
+ drbd_send distinguishes two cases:
+
+ Packets sent via the data socket "sock"
+ and packets sent via the meta data socket "msock"
+
+ sock msock
+ -----------------+-------------------------+------------------------------
+ timeout conf.timeout / 2 conf.timeout / 2
+ timeout action send a ping via msock Abort communication
+ and close all sockets
+*/
+
+/*
+ * you must have down()ed the appropriate [m]sock_mutex elsewhere!
+ */
+int drbd_send(struct drbd_conf *mdev, struct socket *sock,
+ void *buf, size_t size, unsigned msg_flags)
+{
+ struct kvec iov;
+ struct msghdr msg;
+ int rv, sent = 0;
+
+ if (!sock)
+ return -1000;
+
+ /* THINK if (signal_pending) return ... ? */
+
+ iov.iov_base = buf;
+ iov.iov_len = size;
+
+ msg.msg_name = NULL;
+ msg.msg_namelen = 0;
+ msg.msg_control = NULL;
+ msg.msg_controllen = 0;
+ msg.msg_flags = msg_flags | MSG_NOSIGNAL;
+
+ if (sock == mdev->data.socket) {
+ mdev->ko_count = mdev->net_conf->ko_count;
+ drbd_update_congested(mdev);
+ }
+ do {
+ /* STRANGE
+ * tcp_sendmsg does _not_ use its size parameter at all ?
+ *
+ * -EAGAIN on timeout, -EINTR on signal.
+ */
+/* THINK
+ * do we need to block DRBD_SIG if sock == &meta.socket ??
+ * otherwise wake_asender() might interrupt some send_*Ack !
+ */
+ rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
+ if (rv == -EAGAIN) {
+ if (we_should_drop_the_connection(mdev, sock))
+ break;
+ else
+ continue;
+ }
+ D_ASSERT(rv != 0);
+ if (rv == -EINTR) {
+ flush_signals(current);
+ rv = 0;
+ }
+ if (rv < 0)
+ break;
+ sent += rv;
+ iov.iov_base += rv;
+ iov.iov_len -= rv;
+ } while (sent < size);
+
+ if (sock == mdev->data.socket)
+ clear_bit(NET_CONGESTED, &mdev->flags);
+
+ if (rv <= 0) {
+ if (rv != -EAGAIN) {
+ dev_err(DEV, "%s_sendmsg returned %d\n",
+ sock == mdev->meta.socket ? "msock" : "sock",
+ rv);
+ drbd_force_state(mdev, NS(conn, C_BROKEN_PIPE));
+ } else
+ drbd_force_state(mdev, NS(conn, C_TIMEOUT));
+ }
+
+ return sent;
+}
+
+static int drbd_open(struct block_device *bdev, fmode_t mode)
+{
+ struct drbd_conf *mdev = bdev->bd_disk->private_data;
+ unsigned long flags;
+ int rv = 0;
+
+ spin_lock_irqsave(&mdev->req_lock, flags);
+ /* to have a stable mdev->state.role
+ * and no race with updating open_cnt */
+
+ if (mdev->state.role != R_PRIMARY) {
+ if (mode & FMODE_WRITE)
+ rv = -EROFS;
+ else if (!allow_oos)
+ rv = -EMEDIUMTYPE;
+ }
+
+ if (!rv)
+ mdev->open_cnt++;
+ spin_unlock_irqrestore(&mdev->req_lock, flags);
+
+ return rv;
+}
+
+static int drbd_release(struct gendisk *gd, fmode_t mode)
+{
+ struct drbd_conf *mdev = gd->private_data;
+ mdev->open_cnt--;
+ return 0;
+}
+
+STATIC void drbd_unplug_fn(struct request_queue *q)
+{
+ struct drbd_conf *mdev = q->queuedata;
+
+ trace_drbd_unplug(mdev, "got unplugged");
+
+ /* unplug FIRST */
+ spin_lock_irq(q->queue_lock);
+ blk_remove_plug(q);
+ spin_unlock_irq(q->queue_lock);
+
+ /* only if connected */
+ spin_lock_irq(&mdev->req_lock);
+ if (mdev->state.pdsk >= D_INCONSISTENT && mdev->state.conn >= C_CONNECTED) {
+ D_ASSERT(mdev->state.role == R_PRIMARY);
+ if (test_and_clear_bit(UNPLUG_REMOTE, &mdev->flags)) {
+ /* add to the data.work queue,
+ * unless already queued.
+ * XXX this might be a good addition to drbd_queue_work
+ * anyways, to detect "double queuing" ... */
+ if (list_empty(&mdev->unplug_work.list))
+ drbd_queue_work(&mdev->data.work,
+ &mdev->unplug_work);
+ }
+ }
+ spin_unlock_irq(&mdev->req_lock);
+
+ if (mdev->state.disk >= D_INCONSISTENT)
+ drbd_kick_lo(mdev);
+}
+
+STATIC void drbd_set_defaults(struct drbd_conf *mdev)
+{
+ mdev->sync_conf.after = DRBD_AFTER_DEF;
+ mdev->sync_conf.rate = DRBD_RATE_DEF;
+ mdev->sync_conf.al_extents = DRBD_AL_EXTENTS_DEF;
+ mdev->state = (union drbd_state) {
+ { .role = R_SECONDARY,
+ .peer = R_UNKNOWN,
+ .conn = C_STANDALONE,
+ .disk = D_DISKLESS,
+ .pdsk = D_UNKNOWN,
+ .susp = 0
+ } };
+}
+
+void drbd_init_set_defaults(struct drbd_conf *mdev)
+{
+ /* the memset(,0,) did most of this.
+ * note: only assignments, no allocation in here */
+
+ drbd_set_defaults(mdev);
+
+ /* for now, we do NOT yet support it,
+ * even though we start some framework
+ * to eventually support barriers */
+ set_bit(NO_BARRIER_SUPP, &mdev->flags);
+
+ atomic_set(&mdev->ap_bio_cnt, 0);
+ atomic_set(&mdev->ap_pending_cnt, 0);
+ atomic_set(&mdev->rs_pending_cnt, 0);
+ atomic_set(&mdev->unacked_cnt, 0);
+ atomic_set(&mdev->local_cnt, 0);
+ atomic_set(&mdev->net_cnt, 0);
+ atomic_set(&mdev->packet_seq, 0);
+ atomic_set(&mdev->pp_in_use, 0);
+
+ mutex_init(&mdev->md_io_mutex);
+ mutex_init(&mdev->data.mutex);
+ mutex_init(&mdev->meta.mutex);
+ sema_init(&mdev->data.work.s, 0);
+ sema_init(&mdev->meta.work.s, 0);
+ mutex_init(&mdev->state_mutex);
+
+ spin_lock_init(&mdev->data.work.q_lock);
+ spin_lock_init(&mdev->meta.work.q_lock);
+
+ spin_lock_init(&mdev->al_lock);
+ spin_lock_init(&mdev->req_lock);
+ spin_lock_init(&mdev->peer_seq_lock);
+ spin_lock_init(&mdev->epoch_lock);
+
+ INIT_LIST_HEAD(&mdev->active_ee);
+ INIT_LIST_HEAD(&mdev->sync_ee);
+ INIT_LIST_HEAD(&mdev->done_ee);
+ INIT_LIST_HEAD(&mdev->read_ee);
+ INIT_LIST_HEAD(&mdev->net_ee);
+ INIT_LIST_HEAD(&mdev->resync_reads);
+ INIT_LIST_HEAD(&mdev->data.work.q);
+ INIT_LIST_HEAD(&mdev->meta.work.q);
+ INIT_LIST_HEAD(&mdev->resync_work.list);
+ INIT_LIST_HEAD(&mdev->unplug_work.list);
+ INIT_LIST_HEAD(&mdev->md_sync_work.list);
+ INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
+ mdev->resync_work.cb = w_resync_inactive;
+ mdev->unplug_work.cb = w_send_write_hint;
+ mdev->md_sync_work.cb = w_md_sync;
+ mdev->bm_io_work.w.cb = w_bitmap_io;
+ init_timer(&mdev->resync_timer);
+ init_timer(&mdev->md_sync_timer);
+ mdev->resync_timer.function = resync_timer_fn;
+ mdev->resync_timer.data = (unsigned long) mdev;
+ mdev->md_sync_timer.function = md_sync_timer_fn;
+ mdev->md_sync_timer.data = (unsigned long) mdev;
+
+ init_waitqueue_head(&mdev->misc_wait);
+ init_waitqueue_head(&mdev->state_wait);
+ init_waitqueue_head(&mdev->ee_wait);
+ init_waitqueue_head(&mdev->al_wait);
+ init_waitqueue_head(&mdev->seq_wait);
+
+ drbd_thread_init(mdev, &mdev->receiver, drbdd_init);
+ drbd_thread_init(mdev, &mdev->worker, drbd_worker);
+ drbd_thread_init(mdev, &mdev->asender, drbd_asender);
+
+ mdev->agreed_pro_version = PRO_VERSION_MAX;
+ mdev->write_ordering = WO_bio_barrier;
+ mdev->resync_wenr = LC_FREE;
+}
+
+void drbd_mdev_cleanup(struct drbd_conf *mdev)
+{
+ if (mdev->receiver.t_state != None)
+ dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
+ mdev->receiver.t_state);
+
+ /* no need to lock it, I'm the only thread alive */
+ if (atomic_read(&mdev->current_epoch->epoch_size) != 0)
+ dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
+ mdev->al_writ_cnt =
+ mdev->bm_writ_cnt =
+ mdev->read_cnt =
+ mdev->recv_cnt =
+ mdev->send_cnt =
+ mdev->writ_cnt =
+ mdev->p_size =
+ mdev->rs_start =
+ mdev->rs_total =
+ mdev->rs_failed =
+ mdev->rs_mark_left =
+ mdev->rs_mark_time = 0;
+ D_ASSERT(mdev->net_conf == NULL);
+
+ drbd_set_my_capacity(mdev, 0);
+ if (mdev->bitmap) {
+ /* maybe never allocated. */
+ drbd_bm_resize(mdev, 0);
+ drbd_bm_cleanup(mdev);
+ }
+
+ drbd_free_resources(mdev);
+
+ /*
+ * currently we drbd_init_ee only on module load, so
+ * we may do drbd_release_ee only on module unload!
+ */
+ D_ASSERT(list_empty(&mdev->active_ee));
+ D_ASSERT(list_empty(&mdev->sync_ee));
+ D_ASSERT(list_empty(&mdev->done_ee));
+ D_ASSERT(list_empty(&mdev->read_ee));
+ D_ASSERT(list_empty(&mdev->net_ee));
+ D_ASSERT(list_empty(&mdev->resync_reads));
+ D_ASSERT(list_empty(&mdev->data.work.q));
+ D_ASSERT(list_empty(&mdev->meta.work.q));
+ D_ASSERT(list_empty(&mdev->resync_work.list));
+ D_ASSERT(list_empty(&mdev->unplug_work.list));
+
+}
+
+
+STATIC void drbd_destroy_mempools(void)
+{
+ struct page *page;
+
+ while (drbd_pp_pool) {
+ page = drbd_pp_pool;
+ drbd_pp_pool = (struct page *)page_private(page);
+ __free_page(page);
+ drbd_pp_vacant--;
+ }
+
+ /* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */
+
+ if (drbd_ee_mempool)
+ mempool_destroy(drbd_ee_mempool);
+ if (drbd_request_mempool)
+ mempool_destroy(drbd_request_mempool);
+ if (drbd_ee_cache)
+ kmem_cache_destroy(drbd_ee_cache);
+ if (drbd_request_cache)
+ kmem_cache_destroy(drbd_request_cache);
+
+ drbd_ee_mempool = NULL;
+ drbd_request_mempool = NULL;
+ drbd_ee_cache = NULL;
+ drbd_request_cache = NULL;
+
+ return;
+}
+
+STATIC int drbd_create_mempools(void)
+{
+ struct page *page;
+ const int number = (DRBD_MAX_SEGMENT_SIZE/PAGE_SIZE) * minor_count;
+ int i;
+
+ /* prepare our caches and mempools */
+ drbd_request_mempool = NULL;
+ drbd_ee_cache = NULL;
+ drbd_request_cache = NULL;
+ drbd_pp_pool = NULL;
+
+ /* caches */
+ drbd_request_cache = kmem_cache_create(
+ "drbd_req_cache", sizeof(struct drbd_request), 0, 0, NULL);
+ if (drbd_request_cache == NULL)
+ goto Enomem;
+
+ drbd_ee_cache = kmem_cache_create(
+ "drbd_ee_cache", sizeof(struct drbd_epoch_entry), 0, 0, NULL);
+ if (drbd_ee_cache == NULL)
+ goto Enomem;
+
+ /* mempools */
+ drbd_request_mempool = mempool_create(number,
+ mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
+ if (drbd_request_mempool == NULL)
+ goto Enomem;
+
+ drbd_ee_mempool = mempool_create(number,
+ mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
+ if (drbd_request_mempool == NULL)
+ goto Enomem;
+
+ /* drbd's page pool */
+ spin_lock_init(&drbd_pp_lock);
+
+ for (i = 0; i < number; i++) {
+ page = alloc_page(GFP_HIGHUSER);
+ if (!page)
+ goto Enomem;
+ set_page_private(page, (unsigned long)drbd_pp_pool);
+ drbd_pp_pool = page;
+ }
+ drbd_pp_vacant = number;
+
+ return 0;
+
+Enomem:
+ drbd_destroy_mempools(); /* in case we allocated some */
+ return -ENOMEM;
+}
+
+STATIC int drbd_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ /* just so we have it. you never know what interessting things we
+ * might want to do here some day...
+ */
+
+ return NOTIFY_DONE;
+}
+
+STATIC struct notifier_block drbd_notifier = {
+ .notifier_call = drbd_notify_sys,
+};
+
+static void drbd_release_ee_lists(struct drbd_conf *mdev)
+{
+ int rr;
+
+ rr = drbd_release_ee(mdev, &mdev->active_ee);
+ if (rr)
+ dev_err(DEV, "%d EEs in active list found!\n", rr);
+
+ rr = drbd_release_ee(mdev, &mdev->sync_ee);
+ if (rr)
+ dev_err(DEV, "%d EEs in sync list found!\n", rr);
+
+ rr = drbd_release_ee(mdev, &mdev->read_ee);
+ if (rr)
+ dev_err(DEV, "%d EEs in read list found!\n", rr);
+
+ rr = drbd_release_ee(mdev, &mdev->done_ee);
+ if (rr)
+ dev_err(DEV, "%d EEs in done list found!\n", rr);
+
+ rr = drbd_release_ee(mdev, &mdev->net_ee);
+ if (rr)
+ dev_err(DEV, "%d EEs in net list found!\n", rr);
+}
+
+/* caution. no locking.
+ * currently only used from module cleanup code. */
+static void drbd_delete_device(unsigned int minor)
+{
+ struct drbd_conf *mdev = minor_to_mdev(minor);
+
+ if (!mdev)
+ return;
+
+ /* paranoia asserts */
+ if (mdev->open_cnt != 0)
+ dev_err(DEV, "open_cnt = %d in %s:%u", mdev->open_cnt,
+ __FILE__ , __LINE__);
+
+ ERR_IF (!list_empty(&mdev->data.work.q)) {
+ struct list_head *lp;
+ list_for_each(lp, &mdev->data.work.q) {
+ DUMPP(lp);
+ }
+ };
+ /* end paranoia asserts */
+
+ del_gendisk(mdev->vdisk);
+
+ /* cleanup stuff that may have been allocated during
+ * device (re-)configuration or state changes */
+
+ if (mdev->this_bdev)
+ bdput(mdev->this_bdev);
+
+ drbd_free_resources(mdev);
+
+ drbd_release_ee_lists(mdev);
+
+ /* should be free'd on disconnect? */
+ kfree(mdev->ee_hash);
+ /*
+ mdev->ee_hash_s = 0;
+ mdev->ee_hash = NULL;
+ */
+
+ lc_destroy(mdev->act_log);
+ lc_destroy(mdev->resync);
+
+ kfree(mdev->p_uuid);
+ /* mdev->p_uuid = NULL; */
+
+ kfree(mdev->int_dig_out);
+ kfree(mdev->int_dig_in);
+ kfree(mdev->int_dig_vv);
+
+ /* cleanup the rest that has been
+ * allocated from drbd_new_device
+ * and actually free the mdev itself */
+ drbd_free_mdev(mdev);
+}
+
+STATIC void drbd_cleanup(void)
+{
+ unsigned int i;
+
+ unregister_reboot_notifier(&drbd_notifier);
+
+ drbd_nl_cleanup();
+
+ if (minor_table) {
+ if (drbd_proc)
+ remove_proc_entry("drbd", NULL);
+ i = minor_count;
+ while (i--)
+ drbd_delete_device(i);
+ drbd_destroy_mempools();
+ }
+
+ kfree(minor_table);
+
+ unregister_blkdev(DRBD_MAJOR, "drbd");
+
+ printk(KERN_INFO "drbd: module cleanup done.\n");
+}
+
+/**
+ * drbd_congested() - Callback for pdflush
+ * @congested_data: User data
+ * @bdi_bits: Bits pdflush is currently interested in
+ *
+ * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
+ */
+static int drbd_congested(void *congested_data, int bdi_bits)
+{
+ struct drbd_conf *mdev = congested_data;
+ struct request_queue *q;
+ char reason = '-';
+ int r = 0;
+
+ if (!__inc_ap_bio_cond(mdev)) {
+ /* DRBD has frozen IO */
+ r = bdi_bits;
+ reason = 'd';
+ goto out;
+ }
+
+ if (get_ldev(mdev)) {
+ q = bdev_get_queue(mdev->ldev->backing_bdev);
+ r = bdi_congested(&q->backing_dev_info, bdi_bits);
+ put_ldev(mdev);
+ if (r)
+ reason = 'b';
+ }
+
+ if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->flags)) {
+ r |= (1 << BDI_async_congested);
+ reason = reason == 'b' ? 'a' : 'n';
+ }
+
+out:
+ mdev->congestion_reason = reason;
+ return r;
+}
+
+struct drbd_conf *drbd_new_device(unsigned int minor)
+{
+ struct drbd_conf *mdev;
+ struct gendisk *disk;
+ struct request_queue *q;
+
+ mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
+ if (!mdev)
+ return NULL;
+
+ mdev->minor = minor;
+
+ drbd_init_set_defaults(mdev);
+
+ q = blk_alloc_queue(GFP_KERNEL);
+ if (!q)
+ goto out_no_q;
+ mdev->rq_queue = q;
+ q->queuedata = mdev;
+ q->max_segment_size = DRBD_MAX_SEGMENT_SIZE;
+
+ disk = alloc_disk(1);
+ if (!disk)
+ goto out_no_disk;
+ mdev->vdisk = disk;
+
+ set_disk_ro(disk, TRUE);
+
+ disk->queue = q;
+ disk->major = DRBD_MAJOR;
+ disk->first_minor = minor;
+ disk->fops = &drbd_ops;
+ sprintf(disk->disk_name, "drbd%d", minor);
+ disk->private_data = mdev;
+
+ mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
+ /* we have no partitions. we contain only ourselves. */
+ mdev->this_bdev->bd_contains = mdev->this_bdev;
+
+ q->backing_dev_info.congested_fn = drbd_congested;
+ q->backing_dev_info.congested_data = mdev;
+
+ blk_queue_make_request(q, drbd_make_request_26);
+ blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
+ blk_queue_merge_bvec(q, drbd_merge_bvec);
+ q->queue_lock = &mdev->req_lock; /* needed since we use */
+ /* plugging on a queue, that actually has no requests! */
+ q->unplug_fn = drbd_unplug_fn;
+
+ mdev->md_io_page = alloc_page(GFP_KERNEL);
+ if (!mdev->md_io_page)
+ goto out_no_io_page;
+
+ if (drbd_bm_init(mdev))
+ goto out_no_bitmap;
+ /* no need to lock access, we are still initializing the module. */
+ if (!tl_init(mdev))
+ goto out_no_tl;
+
+ mdev->app_reads_hash = kzalloc(APP_R_HSIZE*sizeof(void *), GFP_KERNEL);
+ if (!mdev->app_reads_hash)
+ goto out_no_app_reads;
+
+ mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
+ if (!mdev->current_epoch)
+ goto out_no_epoch;
+
+ INIT_LIST_HEAD(&mdev->current_epoch->list);
+ mdev->epochs = 1;
+
+ return mdev;
+
+/* out_whatever_else:
+ kfree(mdev->current_epoch); */
+out_no_epoch:
+ kfree(mdev->app_reads_hash);
+out_no_app_reads:
+ tl_cleanup(mdev);
+out_no_tl:
+ drbd_bm_cleanup(mdev);
+out_no_bitmap:
+ __free_page(mdev->md_io_page);
+out_no_io_page:
+ put_disk(disk);
+out_no_disk:
+ blk_cleanup_queue(q);
+out_no_q:
+ kfree(mdev);
+ return NULL;
+}
+
+/* counterpart of drbd_new_device.
+ * last part of drbd_delete_device. */
+void drbd_free_mdev(struct drbd_conf *mdev)
+{
+ kfree(mdev->current_epoch);
+ kfree(mdev->app_reads_hash);
+ tl_cleanup(mdev);
+ if (mdev->bitmap) /* should no longer be there. */
+ drbd_bm_cleanup(mdev);
+ __free_page(mdev->md_io_page);
+ put_disk(mdev->vdisk);
+ blk_cleanup_queue(mdev->rq_queue);
+ kfree(mdev);
+}
+
+
+int __init drbd_init(void)
+{
+ int err;
+
+ if (sizeof(struct p_handshake) != 80) {
+ printk(KERN_ERR
+ "drbd: never change the size or layout "
+ "of the HandShake packet.\n");
+ return -EINVAL;
+ }
+
+ if (1 > minor_count || minor_count > 255) {
+ printk(KERN_ERR
+ "drbd: invalid minor_count (%d)\n", minor_count);
+#ifdef MODULE
+ return -EINVAL;
+#else
+ minor_count = 8;
+#endif
+ }
+
+ err = drbd_nl_init();
+ if (err)
+ return err;
+
+ err = register_blkdev(DRBD_MAJOR, "drbd");
+ if (err) {
+ printk(KERN_ERR
+ "drbd: unable to register block device major %d\n",
+ DRBD_MAJOR);
+ return err;
+ }
+
+ register_reboot_notifier(&drbd_notifier);
+
+ /*
+ * allocate all necessary structs
+ */
+ err = -ENOMEM;
+
+ init_waitqueue_head(&drbd_pp_wait);
+
+ drbd_proc = NULL; /* play safe for drbd_cleanup */
+ minor_table = kzalloc(sizeof(struct drbd_conf *)*minor_count,
+ GFP_KERNEL);
+ if (!minor_table)
+ goto Enomem;
+
+ err = drbd_create_mempools();
+ if (err)
+ goto Enomem;
+
+ drbd_proc = proc_create("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops);
+ if (!drbd_proc) {
+ printk(KERN_ERR "drbd: unable to register proc file\n");
+ goto Enomem;
+ }
+
+ rwlock_init(&global_state_lock);
+
+ printk(KERN_INFO "drbd: initialised. "
+ "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
+ API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
+ printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
+ printk(KERN_INFO "drbd: registered as block device major %d\n",
+ DRBD_MAJOR);
+ printk(KERN_INFO "drbd: minor_table @ 0x%p\n", minor_table);
+
+ return 0; /* Success! */
+
+Enomem:
+ drbd_cleanup();
+ if (err == -ENOMEM)
+ /* currently always the case */
+ printk(KERN_ERR "drbd: ran out of memory\n");
+ else
+ printk(KERN_ERR "drbd: initialization failure\n");
+ return err;
+}
+
+void drbd_free_bc(struct drbd_backing_dev *ldev)
+{
+ if (ldev == NULL)
+ return;
+
+ bd_release(ldev->backing_bdev);
+ bd_release(ldev->md_bdev);
+
+ fput(ldev->lo_file);
+ fput(ldev->md_file);
+
+ kfree(ldev);
+}
+
+void drbd_free_sock(struct drbd_conf *mdev)
+{
+ if (mdev->data.socket) {
+ sock_release(mdev->data.socket);
+ mdev->data.socket = NULL;
+ }
+ if (mdev->meta.socket) {
+ sock_release(mdev->meta.socket);
+ mdev->meta.socket = NULL;
+ }
+}
+
+
+void drbd_free_resources(struct drbd_conf *mdev)
+{
+ crypto_free_hash(mdev->csums_tfm);
+ mdev->csums_tfm = NULL;
+ crypto_free_hash(mdev->verify_tfm);
+ mdev->verify_tfm = NULL;
+ crypto_free_hash(mdev->cram_hmac_tfm);
+ mdev->cram_hmac_tfm = NULL;
+ crypto_free_hash(mdev->integrity_w_tfm);
+ mdev->integrity_w_tfm = NULL;
+ crypto_free_hash(mdev->integrity_r_tfm);
+ mdev->integrity_r_tfm = NULL;
+
+ drbd_free_sock(mdev);
+
+ __no_warn(local,
+ drbd_free_bc(mdev->ldev);
+ mdev->ldev = NULL;);
+}
+
+/* meta data management */
+
+struct meta_data_on_disk {
+ u64 la_size; /* last agreed size. */
+ u64 uuid[UI_SIZE]; /* UUIDs. */
+ u64 device_uuid;
+ u64 reserved_u64_1;
+ u32 flags; /* MDF */
+ u32 magic;
+ u32 md_size_sect;
+ u32 al_offset; /* offset to this block */
+ u32 al_nr_extents; /* important for restoring the AL */
+ /* `-- act_log->nr_elements <-- sync_conf.al_extents */
+ u32 bm_offset; /* offset to the bitmap, from here */
+ u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */
+ u32 reserved_u32[4];
+
+} __packed;
+
+/**
+ * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
+ * @mdev: DRBD device.
+ */
+void drbd_md_sync(struct drbd_conf *mdev)
+{
+ struct meta_data_on_disk *buffer;
+ sector_t sector;
+ int i;
+
+ if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
+ return;
+ del_timer(&mdev->md_sync_timer);
+
+ /* We use here D_FAILED and not D_ATTACHING because we try to write
+ * metadata even if we detach due to a disk failure! */
+ if (!get_ldev_if_state(mdev, D_FAILED))
+ return;
+
+ trace_drbd_md_io(mdev, WRITE, mdev->ldev);
+
+ mutex_lock(&mdev->md_io_mutex);
+ buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
+ memset(buffer, 0, 512);
+
+ buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
+ for (i = UI_CURRENT; i < UI_SIZE; i++)
+ buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
+ buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
+ buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);
+
+ buffer->md_size_sect = cpu_to_be32(mdev->ldev->md.md_size_sect);
+ buffer->al_offset = cpu_to_be32(mdev->ldev->md.al_offset);
+ buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
+ buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
+ buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);
+
+ buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
+
+ D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
+ sector = mdev->ldev->md.md_offset;
+
+ if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
+ clear_bit(MD_DIRTY, &mdev->flags);
+ } else {
+ /* this was a try anyways ... */
+ dev_err(DEV, "meta data update failed!\n");
+
+ drbd_chk_io_error(mdev, 1, TRUE);
+ drbd_io_error(mdev, TRUE);
+ }
+
+ /* Update mdev->ldev->md.la_size_sect,
+ * since we updated it on metadata. */
+ mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);
+
+ mutex_unlock(&mdev->md_io_mutex);
+ put_ldev(mdev);
+}
+
+/**
+ * drbd_md_read() - Reads in the meta data super block
+ * @mdev: DRBD device.
+ * @bdev: Device from which the meta data should be read in.
+ *
+ * Return 0 (NO_ERROR) on success, and an enum drbd_ret_codes in case
+ * something goes wrong. Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
+ */
+int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
+{
+ struct meta_data_on_disk *buffer;
+ int i, rv = NO_ERROR;
+
+ if (!get_ldev_if_state(mdev, D_ATTACHING))
+ return ERR_IO_MD_DISK;
+
+ trace_drbd_md_io(mdev, READ, bdev);
+
+ mutex_lock(&mdev->md_io_mutex);
+ buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
+
+ if (!drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
+ /* NOTE: cant do normal error processing here as this is
+ called BEFORE disk is attached */
+ dev_err(DEV, "Error while reading metadata.\n");
+ rv = ERR_IO_MD_DISK;
+ goto err;
+ }
+
+ if (be32_to_cpu(buffer->magic) != DRBD_MD_MAGIC) {
+ dev_err(DEV, "Error while reading metadata, magic not found.\n");
+ rv = ERR_MD_INVALID;
+ goto err;
+ }
+ if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
+ dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
+ be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
+ rv = ERR_MD_INVALID;
+ goto err;
+ }
+ if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
+ dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
+ be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
+ rv = ERR_MD_INVALID;
+ goto err;
+ }
+ if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
+ dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
+ be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
+ rv = ERR_MD_INVALID;
+ goto err;
+ }
+
+ if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
+ dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
+ be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
+ rv = ERR_MD_INVALID;
+ goto err;
+ }
+
+ bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
+ for (i = UI_CURRENT; i < UI_SIZE; i++)
+ bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
+ bdev->md.flags = be32_to_cpu(buffer->flags);
+ mdev->sync_conf.al_extents = be32_to_cpu(buffer->al_nr_extents);
+ bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);
+
+ if (mdev->sync_conf.al_extents < 7)
+ mdev->sync_conf.al_extents = 127;
+
+ err:
+ mutex_unlock(&mdev->md_io_mutex);
+ put_ldev(mdev);
+
+ return rv;
+}
+
+/**
+ * drbd_md_mark_dirty() - Mark meta data super block as dirty
+ * @mdev: DRBD device.
+ *
+ * Call this function if you change enything that should be written to
+ * the meta-data super block. This function sets MD_DIRTY, and starts a
+ * timer that ensures that within five seconds you have to call drbd_md_sync().
+ */
+void drbd_md_mark_dirty(struct drbd_conf *mdev)
+{
+ set_bit(MD_DIRTY, &mdev->flags);
+ mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
+}
+
+
+STATIC void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
+{
+ int i;
+
+ for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) {
+ mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
+
+ trace_drbd_uuid(mdev, i+1);
+ }
+}
+
+void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
+{
+ if (idx == UI_CURRENT) {
+ if (mdev->state.role == R_PRIMARY)
+ val |= 1;
+ else
+ val &= ~((u64)1);
+
+ drbd_set_ed_uuid(mdev, val);
+ }
+
+ mdev->ldev->md.uuid[idx] = val;
+ trace_drbd_uuid(mdev, idx);
+ drbd_md_mark_dirty(mdev);
+}
+
+
+void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
+{
+ if (mdev->ldev->md.uuid[idx]) {
+ drbd_uuid_move_history(mdev);
+ mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
+ trace_drbd_uuid(mdev, UI_HISTORY_START);
+ }
+ _drbd_uuid_set(mdev, idx, val);
+}
+
+/**
+ * drbd_uuid_new_current() - Creates a new current UUID
+ * @mdev: DRBD device.
+ *
+ * Creates a new current UUID, and rotates the old current UUID into
+ * the bitmap slot. Causes an incremental resync upon next connect.
+ */
+void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
+{
+ u64 val;
+
+ dev_info(DEV, "Creating new current UUID\n");
+ D_ASSERT(mdev->ldev->md.uuid[UI_BITMAP] == 0);
+ mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];
+ trace_drbd_uuid(mdev, UI_BITMAP);
+
+ get_random_bytes(&val, sizeof(u64));
+ _drbd_uuid_set(mdev, UI_CURRENT, val);
+}
+
+void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
+{
+ if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
+ return;
+
+ if (val == 0) {
+ drbd_uuid_move_history(mdev);
+ mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
+ mdev->ldev->md.uuid[UI_BITMAP] = 0;
+ trace_drbd_uuid(mdev, UI_HISTORY_START);
+ trace_drbd_uuid(mdev, UI_BITMAP);
+ } else {
+ if (mdev->ldev->md.uuid[UI_BITMAP])
+ dev_warn(DEV, "bm UUID already set");
+
+ mdev->ldev->md.uuid[UI_BITMAP] = val;
+ mdev->ldev->md.uuid[UI_BITMAP] &= ~((u64)1);
+
+ trace_drbd_uuid(mdev, UI_BITMAP);
+ }
+ drbd_md_mark_dirty(mdev);
+}
+
+/**
+ * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
+ * @mdev: DRBD device.
+ *
+ * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
+ */
+int drbd_bmio_set_n_write(struct drbd_conf *mdev)
+{
+ int rv = -EIO;
+
+ if (get_ldev_if_state(mdev, D_ATTACHING)) {
+ drbd_md_set_flag(mdev, MDF_FULL_SYNC);
+ drbd_md_sync(mdev);
+ drbd_bm_set_all(mdev);
+
+ rv = drbd_bm_write(mdev);
+
+ if (!rv) {
+ drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
+ drbd_md_sync(mdev);
+ }
+
+ put_ldev(mdev);
+ }
+
+ return rv;
+}
+
+/**
+ * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
+ * @mdev: DRBD device.
+ *
+ * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
+ */
+int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
+{
+ int rv = -EIO;
+
+ if (get_ldev_if_state(mdev, D_ATTACHING)) {
+ drbd_bm_clear_all(mdev);
+ rv = drbd_bm_write(mdev);
+ put_ldev(mdev);
+ }
+
+ return rv;
+}
+
+STATIC int w_bitmap_io(struct drbd_conf *mdev, struct drbd_work *w, int unused)
+{
+ struct bm_io_work *work = (struct bm_io_work *)w;
+ int rv;
+
+ D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);
+
+ drbd_bm_lock(mdev, work->why);
+ rv = work->io_fn(mdev);
+ drbd_bm_unlock(mdev);
+
+ clear_bit(BITMAP_IO, &mdev->flags);
+ wake_up(&mdev->misc_wait);
+
+ if (work->done)
+ work->done(mdev, rv);
+
+ clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
+ work->why = NULL;
+
+ return 1;
+}
+
+/**
+ * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
+ * @mdev: DRBD device.
+ * @io_fn: IO callback to be called when bitmap IO is possible
+ * @done: callback to be called after the bitmap IO was performed
+ * @why: Descriptive text of the reason for doing the IO
+ *
+ * While IO on the bitmap happens we freeze appliation IO thus we ensure
+ * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
+ * called from worker context. It MUST NOT be used while a previous such
+ * work is still pending!
+ */
+void drbd_queue_bitmap_io(struct drbd_conf *mdev,
+ int (*io_fn)(struct drbd_conf *),
+ void (*done)(struct drbd_conf *, int),
+ char *why)
+{
+ D_ASSERT(current == mdev->worker.task);
+
+ D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
+ D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
+ D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
+ if (mdev->bm_io_work.why)
+ dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
+ why, mdev->bm_io_work.why);
+
+ mdev->bm_io_work.io_fn = io_fn;
+ mdev->bm_io_work.done = done;
+ mdev->bm_io_work.why = why;
+
+ set_bit(BITMAP_IO, &mdev->flags);
+ if (atomic_read(&mdev->ap_bio_cnt) == 0) {
+ if (list_empty(&mdev->bm_io_work.w.list)) {
+ set_bit(BITMAP_IO_QUEUED, &mdev->flags);
+ drbd_queue_work(&mdev->data.work, &mdev->bm_io_work.w);
+ } else
+ dev_err(DEV, "FIXME avoided double queuing bm_io_work\n");
+ }
+}
+
+/**
+ * drbd_bitmap_io() - Does an IO operation on the whole bitmap
+ * @mdev: DRBD device.
+ * @io_fn: IO callback to be called when bitmap IO is possible
+ * @why: Descriptive text of the reason for doing the IO
+ *
+ * freezes application IO while that the actual IO operations runs. This
+ * functions MAY NOT be called from worker context.
+ */
+int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *), char *why)
+{
+ int rv;
+
+ D_ASSERT(current != mdev->worker.task);
+
+ drbd_suspend_io(mdev);
+
+ drbd_bm_lock(mdev, why);
+ rv = io_fn(mdev);
+ drbd_bm_unlock(mdev);
+
+ drbd_resume_io(mdev);
+
+ return rv;
+}
+
+void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
+{
+ if ((mdev->ldev->md.flags & flag) != flag) {
+ drbd_md_mark_dirty(mdev);
+ mdev->ldev->md.flags |= flag;
+ }
+}
+
+void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
+{
+ if ((mdev->ldev->md.flags & flag) != 0) {
+ drbd_md_mark_dirty(mdev);
+ mdev->ldev->md.flags &= ~flag;
+ }
+}
+int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
+{
+ return (bdev->md.flags & flag) != 0;
+}
+
+STATIC void md_sync_timer_fn(unsigned long data)
+{
+ struct drbd_conf *mdev = (struct drbd_conf *) data;
+
+ drbd_queue_work_front(&mdev->data.work, &mdev->md_sync_work);
+}
+
+STATIC int w_md_sync(struct drbd_conf *mdev, struct drbd_work *w, int unused)
+{
+ dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
+ drbd_md_sync(mdev);
+
+ return 1;
+}
+
+#ifdef DRBD_ENABLE_FAULTS
+/* Fault insertion support including random number generator shamelessly
+ * stolen from kernel/rcutorture.c */
+struct fault_random_state {
+ unsigned long state;
+ unsigned long count;
+};
+
+#define FAULT_RANDOM_MULT 39916801 /* prime */
+#define FAULT_RANDOM_ADD 479001701 /* prime */
+#define FAULT_RANDOM_REFRESH 10000
+
+/*
+ * Crude but fast random-number generator. Uses a linear congruential
+ * generator, with occasional help from get_random_bytes().
+ */
+STATIC unsigned long
+_drbd_fault_random(struct fault_random_state *rsp)
+{
+ long refresh;
+
+ if (--rsp->count < 0) {
+ get_random_bytes(&refresh, sizeof(refresh));
+ rsp->state += refresh;
+ rsp->count = FAULT_RANDOM_REFRESH;
+ }
+ rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
+ return swahw32(rsp->state);
+}
+
+STATIC char *
+_drbd_fault_str(unsigned int type) {
+ static char *_faults[] = {
+ "Meta-data write",
+ "Meta-data read",
+ "Resync write",
+ "Resync read",
+ "Data write",
+ "Data read",
+ "Data read ahead",
+ "BM allocation",
+ "EE allocation"
+ };
+
+ return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
+}
+
+unsigned int
+_drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
+{
+ static struct fault_random_state rrs = {0, 0};
+
+ unsigned int ret = (
+ (fault_devs == 0 ||
+ ((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
+ (((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));
+
+ if (ret) {
+ fault_count++;
+
+ if (printk_ratelimit())
+ dev_warn(DEV, "***Simulating %s failure\n",
+ _drbd_fault_str(type));
+ }
+
+ return ret;
+}
+#endif
+
+module_init(drbd_init)
+module_exit(drbd_cleanup)

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  Last update: 2009-05-15 14:15    [from the cache]
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