--- /dev/null
+/* -*- mode: c; c-basic-offset: 8; -*-
+ * vim: noexpandtab sw=8 ts=8 sts=0:
+ *
+ * Copyright (C) 2004, 2005 Oracle. All rights reserved.
+ *
+ * This program 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 of the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/file.h>
+#include <linux/kthread.h>
+#include <linux/configfs.h>
+#include <linux/random.h>
+#include <linux/crc32.h>
+#include <linux/time.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/bitmap.h>
+
+#include "heartbeat.h"
+#include "tcp.h"
+#include "nodemanager.h"
+#include "quorum.h"
+
+#include "masklog.h"
+
+
+/*
+ * The first heartbeat pass had one global thread that would serialize all hb
+ * callback calls. This global serializing sem should only be removed once
+ * we've made sure that all callees can deal with being called concurrently
+ * from multiple hb region threads.
+ */
+static DECLARE_RWSEM(o2hb_callback_sem);
+
+/*
+ * multiple hb threads are watching multiple regions. A node is live
+ * whenever any of the threads sees activity from the node in its region.
+ */
+static DEFINE_SPINLOCK(o2hb_live_lock);
+static struct list_head o2hb_live_slots[O2NM_MAX_NODES];
+static unsigned long o2hb_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
+static LIST_HEAD(o2hb_node_events);
+static DECLARE_WAIT_QUEUE_HEAD(o2hb_steady_queue);
+
+/*
+ * In global heartbeat, we maintain a series of region bitmaps.
+ * - o2hb_region_bitmap allows us to limit the region number to max region.
+ * - o2hb_live_region_bitmap tracks live regions (seen steady iterations).
+ * - o2hb_quorum_region_bitmap tracks live regions that have seen all nodes
+ * heartbeat on it.
+ * - o2hb_failed_region_bitmap tracks the regions that have seen io timeouts.
+ */
+static unsigned long o2hb_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
+static unsigned long o2hb_live_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
+static unsigned long o2hb_quorum_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
+static unsigned long o2hb_failed_region_bitmap[BITS_TO_LONGS(O2NM_MAX_REGIONS)];
+
+#define O2HB_DB_TYPE_LIVENODES 0
+#define O2HB_DB_TYPE_LIVEREGIONS 1
+#define O2HB_DB_TYPE_QUORUMREGIONS 2
+#define O2HB_DB_TYPE_FAILEDREGIONS 3
+#define O2HB_DB_TYPE_REGION_LIVENODES 4
+#define O2HB_DB_TYPE_REGION_NUMBER 5
+#define O2HB_DB_TYPE_REGION_ELAPSED_TIME 6
+#define O2HB_DB_TYPE_REGION_PINNED 7
+struct o2hb_debug_buf {
+ int db_type;
+ int db_size;
+ int db_len;
+ void *db_data;
+};
+
+static struct o2hb_debug_buf *o2hb_db_livenodes;
+static struct o2hb_debug_buf *o2hb_db_liveregions;
+static struct o2hb_debug_buf *o2hb_db_quorumregions;
+static struct o2hb_debug_buf *o2hb_db_failedregions;
+
+#define O2HB_DEBUG_DIR "o2hb"
+#define O2HB_DEBUG_LIVENODES "livenodes"
+#define O2HB_DEBUG_LIVEREGIONS "live_regions"
+#define O2HB_DEBUG_QUORUMREGIONS "quorum_regions"
+#define O2HB_DEBUG_FAILEDREGIONS "failed_regions"
+#define O2HB_DEBUG_REGION_NUMBER "num"
+#define O2HB_DEBUG_REGION_ELAPSED_TIME "elapsed_time_in_ms"
+#define O2HB_DEBUG_REGION_PINNED "pinned"
+
+static struct dentry *o2hb_debug_dir;
+static struct dentry *o2hb_debug_livenodes;
+static struct dentry *o2hb_debug_liveregions;
+static struct dentry *o2hb_debug_quorumregions;
+static struct dentry *o2hb_debug_failedregions;
+
+static LIST_HEAD(o2hb_all_regions);
+
+static struct o2hb_callback {
+ struct list_head list;
+} o2hb_callbacks[O2HB_NUM_CB];
+
+static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type);
+
+#define O2HB_DEFAULT_BLOCK_BITS 9
+
+enum o2hb_heartbeat_modes {
+ O2HB_HEARTBEAT_LOCAL = 0,
+ O2HB_HEARTBEAT_GLOBAL,
+ O2HB_HEARTBEAT_NUM_MODES,
+};
+
+char *o2hb_heartbeat_mode_desc[O2HB_HEARTBEAT_NUM_MODES] = {
+ "local", /* O2HB_HEARTBEAT_LOCAL */
+ "global", /* O2HB_HEARTBEAT_GLOBAL */
+};
+
+unsigned int o2hb_dead_threshold = O2HB_DEFAULT_DEAD_THRESHOLD;
+unsigned int o2hb_heartbeat_mode = O2HB_HEARTBEAT_LOCAL;
+
+/*
+ * o2hb_dependent_users tracks the number of registered callbacks that depend
+ * on heartbeat. o2net and o2dlm are two entities that register this callback.
+ * However only o2dlm depends on the heartbeat. It does not want the heartbeat
+ * to stop while a dlm domain is still active.
+ */
+unsigned int o2hb_dependent_users;
+
+/*
+ * In global heartbeat mode, all regions are pinned if there are one or more
+ * dependent users and the quorum region count is <= O2HB_PIN_CUT_OFF. All
+ * regions are unpinned if the region count exceeds the cut off or the number
+ * of dependent users falls to zero.
+ */
+#define O2HB_PIN_CUT_OFF 3
+
+/*
+ * In local heartbeat mode, we assume the dlm domain name to be the same as
+ * region uuid. This is true for domains created for the file system but not
+ * necessarily true for userdlm domains. This is a known limitation.
+ *
+ * In global heartbeat mode, we pin/unpin all o2hb regions. This solution
+ * works for both file system and userdlm domains.
+ */
+static int o2hb_region_pin(const char *region_uuid);
+static void o2hb_region_unpin(const char *region_uuid);
+
+/* Only sets a new threshold if there are no active regions.
+ *
+ * No locking or otherwise interesting code is required for reading
+ * o2hb_dead_threshold as it can't change once regions are active and
+ * it's not interesting to anyone until then anyway. */
+static void o2hb_dead_threshold_set(unsigned int threshold)
+{
+ if (threshold > O2HB_MIN_DEAD_THRESHOLD) {
+ spin_lock(&o2hb_live_lock);
+ if (list_empty(&o2hb_all_regions))
+ o2hb_dead_threshold = threshold;
+ spin_unlock(&o2hb_live_lock);
+ }
+}
+
+static int o2hb_global_heartbeat_mode_set(unsigned int hb_mode)
+{
+ int ret = -1;
+
+ if (hb_mode < O2HB_HEARTBEAT_NUM_MODES) {
+ spin_lock(&o2hb_live_lock);
+ if (list_empty(&o2hb_all_regions)) {
+ o2hb_heartbeat_mode = hb_mode;
+ ret = 0;
+ }
+ spin_unlock(&o2hb_live_lock);
+ }
+
+ return ret;
+}
+
+struct o2hb_node_event {
+ struct list_head hn_item;
+ enum o2hb_callback_type hn_event_type;
+ struct o2nm_node *hn_node;
+ int hn_node_num;
+};
+
+struct o2hb_disk_slot {
+ struct o2hb_disk_heartbeat_block *ds_raw_block;
+ u8 ds_node_num;
+ u64 ds_last_time;
+ u64 ds_last_generation;
+ u16 ds_equal_samples;
+ u16 ds_changed_samples;
+ struct list_head ds_live_item;
+};
+
+/* each thread owns a region.. when we're asked to tear down the region
+ * we ask the thread to stop, who cleans up the region */
+struct o2hb_region {
+ struct config_item hr_item;
+
+ struct list_head hr_all_item;
+ unsigned hr_unclean_stop:1,
+ hr_aborted_start:1,
+ hr_item_pinned:1,
+ hr_item_dropped:1;
+
+ /* protected by the hr_callback_sem */
+ struct task_struct *hr_task;
+
+ unsigned int hr_blocks;
+ unsigned long long hr_start_block;
+
+ unsigned int hr_block_bits;
+ unsigned int hr_block_bytes;
+
+ unsigned int hr_slots_per_page;
+ unsigned int hr_num_pages;
+
+ struct page **hr_slot_data;
+ struct block_device *hr_bdev;
+ struct o2hb_disk_slot *hr_slots;
+
+ /* live node map of this region */
+ unsigned long hr_live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ unsigned int hr_region_num;
+
+ struct dentry *hr_debug_dir;
+ struct dentry *hr_debug_livenodes;
+ struct dentry *hr_debug_regnum;
+ struct dentry *hr_debug_elapsed_time;
+ struct dentry *hr_debug_pinned;
+ struct o2hb_debug_buf *hr_db_livenodes;
+ struct o2hb_debug_buf *hr_db_regnum;
+ struct o2hb_debug_buf *hr_db_elapsed_time;
+ struct o2hb_debug_buf *hr_db_pinned;
+
+ /* let the person setting up hb wait for it to return until it
+ * has reached a 'steady' state. This will be fixed when we have
+ * a more complete api that doesn't lead to this sort of fragility. */
+ atomic_t hr_steady_iterations;
+
+ /* terminate o2hb thread if it does not reach steady state
+ * (hr_steady_iterations == 0) within hr_unsteady_iterations */
+ atomic_t hr_unsteady_iterations;
+
+ char hr_dev_name[BDEVNAME_SIZE];
+
+ unsigned int hr_timeout_ms;
+
+ /* randomized as the region goes up and down so that a node
+ * recognizes a node going up and down in one iteration */
+ u64 hr_generation;
+
+ struct delayed_work hr_write_timeout_work;
+ unsigned long hr_last_timeout_start;
+
+ /* Used during o2hb_check_slot to hold a copy of the block
+ * being checked because we temporarily have to zero out the
+ * crc field. */
+ struct o2hb_disk_heartbeat_block *hr_tmp_block;
+};
+
+struct o2hb_bio_wait_ctxt {
+ atomic_t wc_num_reqs;
+ struct completion wc_io_complete;
+ int wc_error;
+};
+
+static void o2hb_write_timeout(struct work_struct *work)
+{
+ int failed, quorum;
+ unsigned long flags;
+ struct o2hb_region *reg =
+ container_of(work, struct o2hb_region,
+ hr_write_timeout_work.work);
+
+ mlog(ML_ERROR, "Heartbeat write timeout to device %s after %u "
+ "milliseconds\n", reg->hr_dev_name,
+ jiffies_to_msecs(jiffies - reg->hr_last_timeout_start));
+
+ if (o2hb_global_heartbeat_active()) {
+ spin_lock_irqsave(&o2hb_live_lock, flags);
+ if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ set_bit(reg->hr_region_num, o2hb_failed_region_bitmap);
+ failed = bitmap_weight(o2hb_failed_region_bitmap,
+ O2NM_MAX_REGIONS);
+ quorum = bitmap_weight(o2hb_quorum_region_bitmap,
+ O2NM_MAX_REGIONS);
+ spin_unlock_irqrestore(&o2hb_live_lock, flags);
+
+ mlog(ML_HEARTBEAT, "Number of regions %d, failed regions %d\n",
+ quorum, failed);
+
+ /*
+ * Fence if the number of failed regions >= half the number
+ * of quorum regions
+ */
+ if ((failed << 1) < quorum)
+ return;
+ }
+
+ o2quo_disk_timeout();
+}
+
+static void o2hb_arm_write_timeout(struct o2hb_region *reg)
+{
+ /* Arm writeout only after thread reaches steady state */
+ if (atomic_read(®->hr_steady_iterations) != 0)
+ return;
+
+ mlog(ML_HEARTBEAT, "Queue write timeout for %u ms\n",
+ O2HB_MAX_WRITE_TIMEOUT_MS);
+
+ if (o2hb_global_heartbeat_active()) {
+ spin_lock(&o2hb_live_lock);
+ clear_bit(reg->hr_region_num, o2hb_failed_region_bitmap);
+ spin_unlock(&o2hb_live_lock);
+ }
+ cancel_delayed_work(®->hr_write_timeout_work);
+ reg->hr_last_timeout_start = jiffies;
+ schedule_delayed_work(®->hr_write_timeout_work,
+ msecs_to_jiffies(O2HB_MAX_WRITE_TIMEOUT_MS));
+}
+
+static void o2hb_disarm_write_timeout(struct o2hb_region *reg)
+{
+ cancel_delayed_work_sync(®->hr_write_timeout_work);
+}
+
+static inline void o2hb_bio_wait_init(struct o2hb_bio_wait_ctxt *wc)
+{
+ atomic_set(&wc->wc_num_reqs, 1);
+ init_completion(&wc->wc_io_complete);
+ wc->wc_error = 0;
+}
+
+/* Used in error paths too */
+static inline void o2hb_bio_wait_dec(struct o2hb_bio_wait_ctxt *wc,
+ unsigned int num)
+{
+ /* sadly atomic_sub_and_test() isn't available on all platforms. The
+ * good news is that the fast path only completes one at a time */
+ while(num--) {
+ if (atomic_dec_and_test(&wc->wc_num_reqs)) {
+ BUG_ON(num > 0);
+ complete(&wc->wc_io_complete);
+ }
+ }
+}
+
+static void o2hb_wait_on_io(struct o2hb_region *reg,
+ struct o2hb_bio_wait_ctxt *wc)
+{
+ o2hb_bio_wait_dec(wc, 1);
+ wait_for_completion(&wc->wc_io_complete);
+}
+
+static void o2hb_bio_end_io(struct bio *bio,
+ int error)
+{
+ struct o2hb_bio_wait_ctxt *wc = bio->bi_private;
+
+ if (error) {
+ mlog(ML_ERROR, "IO Error %d\n", error);
+ wc->wc_error = error;
+ }
+
+ o2hb_bio_wait_dec(wc, 1);
+ bio_put(bio);
+}
+
+/* Setup a Bio to cover I/O against num_slots slots starting at
+ * start_slot. */
+static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg,
+ struct o2hb_bio_wait_ctxt *wc,
+ unsigned int *current_slot,
+ unsigned int max_slots)
+{
+ int len, current_page;
+ unsigned int vec_len, vec_start;
+ unsigned int bits = reg->hr_block_bits;
+ unsigned int spp = reg->hr_slots_per_page;
+ unsigned int cs = *current_slot;
+ struct bio *bio;
+ struct page *page;
+
+ /* Testing has shown this allocation to take long enough under
+ * GFP_KERNEL that the local node can get fenced. It would be
+ * nicest if we could pre-allocate these bios and avoid this
+ * all together. */
+ bio = bio_alloc(GFP_ATOMIC, 16);
+ if (!bio) {
+ mlog(ML_ERROR, "Could not alloc slots BIO!\n");
+ bio = ERR_PTR(-ENOMEM);
+ goto bail;
+ }
+
+ /* Must put everything in 512 byte sectors for the bio... */
+ bio->bi_iter.bi_sector = (reg->hr_start_block + cs) << (bits - 9);
+ bio->bi_bdev = reg->hr_bdev;
+ bio->bi_private = wc;
+ bio->bi_end_io = o2hb_bio_end_io;
+
+ vec_start = (cs << bits) % PAGE_CACHE_SIZE;
+ while(cs < max_slots) {
+ current_page = cs / spp;
+ page = reg->hr_slot_data[current_page];
+
+ vec_len = min(PAGE_CACHE_SIZE - vec_start,
+ (max_slots-cs) * (PAGE_CACHE_SIZE/spp) );
+
+ mlog(ML_HB_BIO, "page %d, vec_len = %u, vec_start = %u\n",
+ current_page, vec_len, vec_start);
+
+ len = bio_add_page(bio, page, vec_len, vec_start);
+ if (len != vec_len) break;
+
+ cs += vec_len / (PAGE_CACHE_SIZE/spp);
+ vec_start = 0;
+ }
+
+bail:
+ *current_slot = cs;
+ return bio;
+}
+
+static int o2hb_read_slots(struct o2hb_region *reg,
+ unsigned int max_slots)
+{
+ unsigned int current_slot=0;
+ int status;
+ struct o2hb_bio_wait_ctxt wc;
+ struct bio *bio;
+
+ o2hb_bio_wait_init(&wc);
+
+ while(current_slot < max_slots) {
+ bio = o2hb_setup_one_bio(reg, &wc, ¤t_slot, max_slots);
+ if (IS_ERR(bio)) {
+ status = PTR_ERR(bio);
+ mlog_errno(status);
+ goto bail_and_wait;
+ }
+
+ atomic_inc(&wc.wc_num_reqs);
+ submit_bio(READ, bio);
+ }
+
+ status = 0;
+
+bail_and_wait:
+ o2hb_wait_on_io(reg, &wc);
+ if (wc.wc_error && !status)
+ status = wc.wc_error;
+
+ return status;
+}
+
+static int o2hb_issue_node_write(struct o2hb_region *reg,
+ struct o2hb_bio_wait_ctxt *write_wc)
+{
+ int status;
+ unsigned int slot;
+ struct bio *bio;
+
+ o2hb_bio_wait_init(write_wc);
+
+ slot = o2nm_this_node();
+
+ bio = o2hb_setup_one_bio(reg, write_wc, &slot, slot+1);
+ if (IS_ERR(bio)) {
+ status = PTR_ERR(bio);
+ mlog_errno(status);
+ goto bail;
+ }
+
+ atomic_inc(&write_wc->wc_num_reqs);
+ submit_bio(WRITE_SYNC, bio);
+
+ status = 0;
+bail:
+ return status;
+}
+
+static u32 o2hb_compute_block_crc_le(struct o2hb_region *reg,
+ struct o2hb_disk_heartbeat_block *hb_block)
+{
+ __le32 old_cksum;
+ u32 ret;
+
+ /* We want to compute the block crc with a 0 value in the
+ * hb_cksum field. Save it off here and replace after the
+ * crc. */
+ old_cksum = hb_block->hb_cksum;
+ hb_block->hb_cksum = 0;
+
+ ret = crc32_le(0, (unsigned char *) hb_block, reg->hr_block_bytes);
+
+ hb_block->hb_cksum = old_cksum;
+
+ return ret;
+}
+
+static void o2hb_dump_slot(struct o2hb_disk_heartbeat_block *hb_block)
+{
+ mlog(ML_ERROR, "Dump slot information: seq = 0x%llx, node = %u, "
+ "cksum = 0x%x, generation 0x%llx\n",
+ (long long)le64_to_cpu(hb_block->hb_seq),
+ hb_block->hb_node, le32_to_cpu(hb_block->hb_cksum),
+ (long long)le64_to_cpu(hb_block->hb_generation));
+}
+
+static int o2hb_verify_crc(struct o2hb_region *reg,
+ struct o2hb_disk_heartbeat_block *hb_block)
+{
+ u32 read, computed;
+
+ read = le32_to_cpu(hb_block->hb_cksum);
+ computed = o2hb_compute_block_crc_le(reg, hb_block);
+
+ return read == computed;
+}
+
+/*
+ * Compare the slot data with what we wrote in the last iteration.
+ * If the match fails, print an appropriate error message. This is to
+ * detect errors like... another node hearting on the same slot,
+ * flaky device that is losing writes, etc.
+ * Returns 1 if check succeeds, 0 otherwise.
+ */
+static int o2hb_check_own_slot(struct o2hb_region *reg)
+{
+ struct o2hb_disk_slot *slot;
+ struct o2hb_disk_heartbeat_block *hb_block;
+ char *errstr;
+
+ slot = ®->hr_slots[o2nm_this_node()];
+ /* Don't check on our 1st timestamp */
+ if (!slot->ds_last_time)
+ return 0;
+
+ hb_block = slot->ds_raw_block;
+ if (le64_to_cpu(hb_block->hb_seq) == slot->ds_last_time &&
+ le64_to_cpu(hb_block->hb_generation) == slot->ds_last_generation &&
+ hb_block->hb_node == slot->ds_node_num)
+ return 1;
+
+#define ERRSTR1 "Another node is heartbeating on device"
+#define ERRSTR2 "Heartbeat generation mismatch on device"
+#define ERRSTR3 "Heartbeat sequence mismatch on device"
+
+ if (hb_block->hb_node != slot->ds_node_num)
+ errstr = ERRSTR1;
+ else if (le64_to_cpu(hb_block->hb_generation) !=
+ slot->ds_last_generation)
+ errstr = ERRSTR2;
+ else
+ errstr = ERRSTR3;
+
+ mlog(ML_ERROR, "%s (%s): expected(%u:0x%llx, 0x%llx), "
+ "ondisk(%u:0x%llx, 0x%llx)\n", errstr, reg->hr_dev_name,
+ slot->ds_node_num, (unsigned long long)slot->ds_last_generation,
+ (unsigned long long)slot->ds_last_time, hb_block->hb_node,
+ (unsigned long long)le64_to_cpu(hb_block->hb_generation),
+ (unsigned long long)le64_to_cpu(hb_block->hb_seq));
+
+ return 0;
+}
+
+static inline void o2hb_prepare_block(struct o2hb_region *reg,
+ u64 generation)
+{
+ int node_num;
+ u64 cputime;
+ struct o2hb_disk_slot *slot;
+ struct o2hb_disk_heartbeat_block *hb_block;
+
+ node_num = o2nm_this_node();
+ slot = ®->hr_slots[node_num];
+
+ hb_block = (struct o2hb_disk_heartbeat_block *)slot->ds_raw_block;
+ memset(hb_block, 0, reg->hr_block_bytes);
+ /* TODO: time stuff */
+ cputime = CURRENT_TIME.tv_sec;
+ if (!cputime)
+ cputime = 1;
+
+ hb_block->hb_seq = cpu_to_le64(cputime);
+ hb_block->hb_node = node_num;
+ hb_block->hb_generation = cpu_to_le64(generation);
+ hb_block->hb_dead_ms = cpu_to_le32(o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS);
+
+ /* This step must always happen last! */
+ hb_block->hb_cksum = cpu_to_le32(o2hb_compute_block_crc_le(reg,
+ hb_block));
+
+ mlog(ML_HB_BIO, "our node generation = 0x%llx, cksum = 0x%x\n",
+ (long long)generation,
+ le32_to_cpu(hb_block->hb_cksum));
+}
+
+static void o2hb_fire_callbacks(struct o2hb_callback *hbcall,
+ struct o2nm_node *node,
+ int idx)
+{
+ struct o2hb_callback_func *f;
+
+ list_for_each_entry(f, &hbcall->list, hc_item) {
+ mlog(ML_HEARTBEAT, "calling funcs %p\n", f);
+ (f->hc_func)(node, idx, f->hc_data);
+ }
+}
+
+/* Will run the list in order until we process the passed event */
+static void o2hb_run_event_list(struct o2hb_node_event *queued_event)
+{
+ struct o2hb_callback *hbcall;
+ struct o2hb_node_event *event;
+
+ /* Holding callback sem assures we don't alter the callback
+ * lists when doing this, and serializes ourselves with other
+ * processes wanting callbacks. */
+ down_write(&o2hb_callback_sem);
+
+ spin_lock(&o2hb_live_lock);
+ while (!list_empty(&o2hb_node_events)
+ && !list_empty(&queued_event->hn_item)) {
+ event = list_entry(o2hb_node_events.next,
+ struct o2hb_node_event,
+ hn_item);
+ list_del_init(&event->hn_item);
+ spin_unlock(&o2hb_live_lock);
+
+ mlog(ML_HEARTBEAT, "Node %s event for %d\n",
+ event->hn_event_type == O2HB_NODE_UP_CB ? "UP" : "DOWN",
+ event->hn_node_num);
+
+ hbcall = hbcall_from_type(event->hn_event_type);
+
+ /* We should *never* have gotten on to the list with a
+ * bad type... This isn't something that we should try
+ * to recover from. */
+ BUG_ON(IS_ERR(hbcall));
+
+ o2hb_fire_callbacks(hbcall, event->hn_node, event->hn_node_num);
+
+ spin_lock(&o2hb_live_lock);
+ }
+ spin_unlock(&o2hb_live_lock);
+
+ up_write(&o2hb_callback_sem);
+}
+
+static void o2hb_queue_node_event(struct o2hb_node_event *event,
+ enum o2hb_callback_type type,
+ struct o2nm_node *node,
+ int node_num)
+{
+ assert_spin_locked(&o2hb_live_lock);
+
+ BUG_ON((!node) && (type != O2HB_NODE_DOWN_CB));
+
+ event->hn_event_type = type;
+ event->hn_node = node;
+ event->hn_node_num = node_num;
+
+ mlog(ML_HEARTBEAT, "Queue node %s event for node %d\n",
+ type == O2HB_NODE_UP_CB ? "UP" : "DOWN", node_num);
+
+ list_add_tail(&event->hn_item, &o2hb_node_events);
+}
+
+static void o2hb_shutdown_slot(struct o2hb_disk_slot *slot)
+{
+ struct o2hb_node_event event =
+ { .hn_item = LIST_HEAD_INIT(event.hn_item), };
+ struct o2nm_node *node;
+ int queued = 0;
+
+ node = o2nm_get_node_by_num(slot->ds_node_num);
+ if (!node)
+ return;
+
+ spin_lock(&o2hb_live_lock);
+ if (!list_empty(&slot->ds_live_item)) {
+ mlog(ML_HEARTBEAT, "Shutdown, node %d leaves region\n",
+ slot->ds_node_num);
+
+ list_del_init(&slot->ds_live_item);
+
+ if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
+ clear_bit(slot->ds_node_num, o2hb_live_node_bitmap);
+
+ o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB, node,
+ slot->ds_node_num);
+ queued = 1;
+ }
+ }
+ spin_unlock(&o2hb_live_lock);
+
+ if (queued)
+ o2hb_run_event_list(&event);
+
+ o2nm_node_put(node);
+}
+
+static void o2hb_set_quorum_device(struct o2hb_region *reg)
+{
+ if (!o2hb_global_heartbeat_active())
+ return;
+
+ /* Prevent race with o2hb_heartbeat_group_drop_item() */
+ if (kthread_should_stop())
+ return;
+
+ /* Tag region as quorum only after thread reaches steady state */
+ if (atomic_read(®->hr_steady_iterations) != 0)
+ return;
+
+ spin_lock(&o2hb_live_lock);
+
+ if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ goto unlock;
+
+ /*
+ * A region can be added to the quorum only when it sees all
+ * live nodes heartbeat on it. In other words, the region has been
+ * added to all nodes.
+ */
+ if (memcmp(reg->hr_live_node_bitmap, o2hb_live_node_bitmap,
+ sizeof(o2hb_live_node_bitmap)))
+ goto unlock;
+
+ printk(KERN_NOTICE "o2hb: Region %s (%s) is now a quorum device\n",
+ config_item_name(®->hr_item), reg->hr_dev_name);
+
+ set_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
+
+ /*
+ * If global heartbeat active, unpin all regions if the
+ * region count > CUT_OFF
+ */
+ if (bitmap_weight(o2hb_quorum_region_bitmap,
+ O2NM_MAX_REGIONS) > O2HB_PIN_CUT_OFF)
+ o2hb_region_unpin(NULL);
+unlock:
+ spin_unlock(&o2hb_live_lock);
+}
+
+static int o2hb_check_slot(struct o2hb_region *reg,
+ struct o2hb_disk_slot *slot)
+{
+ int changed = 0, gen_changed = 0;
+ struct o2hb_node_event event =
+ { .hn_item = LIST_HEAD_INIT(event.hn_item), };
+ struct o2nm_node *node;
+ struct o2hb_disk_heartbeat_block *hb_block = reg->hr_tmp_block;
+ u64 cputime;
+ unsigned int dead_ms = o2hb_dead_threshold * O2HB_REGION_TIMEOUT_MS;
+ unsigned int slot_dead_ms;
+ int tmp;
+ int queued = 0;
+
+ memcpy(hb_block, slot->ds_raw_block, reg->hr_block_bytes);
+
+ /*
+ * If a node is no longer configured but is still in the livemap, we
+ * may need to clear that bit from the livemap.
+ */
+ node = o2nm_get_node_by_num(slot->ds_node_num);
+ if (!node) {
+ spin_lock(&o2hb_live_lock);
+ tmp = test_bit(slot->ds_node_num, o2hb_live_node_bitmap);
+ spin_unlock(&o2hb_live_lock);
+ if (!tmp)
+ return 0;
+ }
+
+ if (!o2hb_verify_crc(reg, hb_block)) {
+ /* all paths from here will drop o2hb_live_lock for
+ * us. */
+ spin_lock(&o2hb_live_lock);
+
+ /* Don't print an error on the console in this case -
+ * a freshly formatted heartbeat area will not have a
+ * crc set on it. */
+ if (list_empty(&slot->ds_live_item))
+ goto out;
+
+ /* The node is live but pushed out a bad crc. We
+ * consider it a transient miss but don't populate any
+ * other values as they may be junk. */
+ mlog(ML_ERROR, "Node %d has written a bad crc to %s\n",
+ slot->ds_node_num, reg->hr_dev_name);
+ o2hb_dump_slot(hb_block);
+
+ slot->ds_equal_samples++;
+ goto fire_callbacks;
+ }
+
+ /* we don't care if these wrap.. the state transitions below
+ * clear at the right places */
+ cputime = le64_to_cpu(hb_block->hb_seq);
+ if (slot->ds_last_time != cputime)
+ slot->ds_changed_samples++;
+ else
+ slot->ds_equal_samples++;
+ slot->ds_last_time = cputime;
+
+ /* The node changed heartbeat generations. We assume this to
+ * mean it dropped off but came back before we timed out. We
+ * want to consider it down for the time being but don't want
+ * to lose any changed_samples state we might build up to
+ * considering it live again. */
+ if (slot->ds_last_generation != le64_to_cpu(hb_block->hb_generation)) {
+ gen_changed = 1;
+ slot->ds_equal_samples = 0;
+ mlog(ML_HEARTBEAT, "Node %d changed generation (0x%llx "
+ "to 0x%llx)\n", slot->ds_node_num,
+ (long long)slot->ds_last_generation,
+ (long long)le64_to_cpu(hb_block->hb_generation));
+ }
+
+ slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation);
+
+ mlog(ML_HEARTBEAT, "Slot %d gen 0x%llx cksum 0x%x "
+ "seq %llu last %llu changed %u equal %u\n",
+ slot->ds_node_num, (long long)slot->ds_last_generation,
+ le32_to_cpu(hb_block->hb_cksum),
+ (unsigned long long)le64_to_cpu(hb_block->hb_seq),
+ (unsigned long long)slot->ds_last_time, slot->ds_changed_samples,
+ slot->ds_equal_samples);
+
+ spin_lock(&o2hb_live_lock);
+
+fire_callbacks:
+ /* dead nodes only come to life after some number of
+ * changes at any time during their dead time */
+ if (list_empty(&slot->ds_live_item) &&
+ slot->ds_changed_samples >= O2HB_LIVE_THRESHOLD) {
+ mlog(ML_HEARTBEAT, "Node %d (id 0x%llx) joined my region\n",
+ slot->ds_node_num, (long long)slot->ds_last_generation);
+
+ set_bit(slot->ds_node_num, reg->hr_live_node_bitmap);
+
+ /* first on the list generates a callback */
+ if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
+ mlog(ML_HEARTBEAT, "o2hb: Add node %d to live nodes "
+ "bitmap\n", slot->ds_node_num);
+ set_bit(slot->ds_node_num, o2hb_live_node_bitmap);
+
+ o2hb_queue_node_event(&event, O2HB_NODE_UP_CB, node,
+ slot->ds_node_num);
+
+ changed = 1;
+ queued = 1;
+ }
+
+ list_add_tail(&slot->ds_live_item,
+ &o2hb_live_slots[slot->ds_node_num]);
+
+ slot->ds_equal_samples = 0;
+
+ /* We want to be sure that all nodes agree on the
+ * number of milliseconds before a node will be
+ * considered dead. The self-fencing timeout is
+ * computed from this value, and a discrepancy might
+ * result in heartbeat calling a node dead when it
+ * hasn't self-fenced yet. */
+ slot_dead_ms = le32_to_cpu(hb_block->hb_dead_ms);
+ if (slot_dead_ms && slot_dead_ms != dead_ms) {
+ /* TODO: Perhaps we can fail the region here. */
+ mlog(ML_ERROR, "Node %d on device %s has a dead count "
+ "of %u ms, but our count is %u ms.\n"
+ "Please double check your configuration values "
+ "for 'O2CB_HEARTBEAT_THRESHOLD'\n",
+ slot->ds_node_num, reg->hr_dev_name, slot_dead_ms,
+ dead_ms);
+ }
+ goto out;
+ }
+
+ /* if the list is dead, we're done.. */
+ if (list_empty(&slot->ds_live_item))
+ goto out;
+
+ /* live nodes only go dead after enough consequtive missed
+ * samples.. reset the missed counter whenever we see
+ * activity */
+ if (slot->ds_equal_samples >= o2hb_dead_threshold || gen_changed) {
+ mlog(ML_HEARTBEAT, "Node %d left my region\n",
+ slot->ds_node_num);
+
+ clear_bit(slot->ds_node_num, reg->hr_live_node_bitmap);
+
+ /* last off the live_slot generates a callback */
+ list_del_init(&slot->ds_live_item);
+ if (list_empty(&o2hb_live_slots[slot->ds_node_num])) {
+ mlog(ML_HEARTBEAT, "o2hb: Remove node %d from live "
+ "nodes bitmap\n", slot->ds_node_num);
+ clear_bit(slot->ds_node_num, o2hb_live_node_bitmap);
+
+ /* node can be null */
+ o2hb_queue_node_event(&event, O2HB_NODE_DOWN_CB,
+ node, slot->ds_node_num);
+
+ changed = 1;
+ queued = 1;
+ }
+
+ /* We don't clear this because the node is still
+ * actually writing new blocks. */
+ if (!gen_changed)
+ slot->ds_changed_samples = 0;
+ goto out;
+ }
+ if (slot->ds_changed_samples) {
+ slot->ds_changed_samples = 0;
+ slot->ds_equal_samples = 0;
+ }
+out:
+ spin_unlock(&o2hb_live_lock);
+
+ if (queued)
+ o2hb_run_event_list(&event);
+
+ if (node)
+ o2nm_node_put(node);
+ return changed;
+}
+
+static int o2hb_highest_node(unsigned long *nodes, int numbits)
+{
+ return find_last_bit(nodes, numbits);
+}
+
+static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
+{
+ int i, ret, highest_node;
+ int membership_change = 0, own_slot_ok = 0;
+ unsigned long configured_nodes[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ unsigned long live_node_bitmap[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ struct o2hb_bio_wait_ctxt write_wc;
+
+ ret = o2nm_configured_node_map(configured_nodes,
+ sizeof(configured_nodes));
+ if (ret) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ /*
+ * If a node is not configured but is in the livemap, we still need
+ * to read the slot so as to be able to remove it from the livemap.
+ */
+ o2hb_fill_node_map(live_node_bitmap, sizeof(live_node_bitmap));
+ i = -1;
+ while ((i = find_next_bit(live_node_bitmap,
+ O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) {
+ set_bit(i, configured_nodes);
+ }
+
+ highest_node = o2hb_highest_node(configured_nodes, O2NM_MAX_NODES);
+ if (highest_node >= O2NM_MAX_NODES) {
+ mlog(ML_NOTICE, "o2hb: No configured nodes found!\n");
+ ret = -EINVAL;
+ goto bail;
+ }
+
+ /* No sense in reading the slots of nodes that don't exist
+ * yet. Of course, if the node definitions have holes in them
+ * then we're reading an empty slot anyway... Consider this
+ * best-effort. */
+ ret = o2hb_read_slots(reg, highest_node + 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ /* With an up to date view of the slots, we can check that no
+ * other node has been improperly configured to heartbeat in
+ * our slot. */
+ own_slot_ok = o2hb_check_own_slot(reg);
+
+ /* fill in the proper info for our next heartbeat */
+ o2hb_prepare_block(reg, reg->hr_generation);
+
+ ret = o2hb_issue_node_write(reg, &write_wc);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ i = -1;
+ while((i = find_next_bit(configured_nodes,
+ O2NM_MAX_NODES, i + 1)) < O2NM_MAX_NODES) {
+ membership_change |= o2hb_check_slot(reg, ®->hr_slots[i]);
+ }
+
+ /*
+ * We have to be sure we've advertised ourselves on disk
+ * before we can go to steady state. This ensures that
+ * people we find in our steady state have seen us.
+ */
+ o2hb_wait_on_io(reg, &write_wc);
+ if (write_wc.wc_error) {
+ /* Do not re-arm the write timeout on I/O error - we
+ * can't be sure that the new block ever made it to
+ * disk */
+ mlog(ML_ERROR, "Write error %d on device \"%s\"\n",
+ write_wc.wc_error, reg->hr_dev_name);
+ ret = write_wc.wc_error;
+ goto bail;
+ }
+
+ /* Skip disarming the timeout if own slot has stale/bad data */
+ if (own_slot_ok) {
+ o2hb_set_quorum_device(reg);
+ o2hb_arm_write_timeout(reg);
+ }
+
+bail:
+ /* let the person who launched us know when things are steady */
+ if (atomic_read(®->hr_steady_iterations) != 0) {
+ if (!ret && own_slot_ok && !membership_change) {
+ if (atomic_dec_and_test(®->hr_steady_iterations))
+ wake_up(&o2hb_steady_queue);
+ }
+ }
+
+ if (atomic_read(®->hr_steady_iterations) != 0) {
+ if (atomic_dec_and_test(®->hr_unsteady_iterations)) {
+ printk(KERN_NOTICE "o2hb: Unable to stabilize "
+ "heartbeart on region %s (%s)\n",
+ config_item_name(®->hr_item),
+ reg->hr_dev_name);
+ atomic_set(®->hr_steady_iterations, 0);
+ reg->hr_aborted_start = 1;
+ wake_up(&o2hb_steady_queue);
+ ret = -EIO;
+ }
+ }
+
+ return ret;
+}
+
+/* Subtract b from a, storing the result in a. a *must* have a larger
+ * value than b. */
+static void o2hb_tv_subtract(struct timeval *a,
+ struct timeval *b)
+{
+ /* just return 0 when a is after b */
+ if (a->tv_sec < b->tv_sec ||
+ (a->tv_sec == b->tv_sec && a->tv_usec < b->tv_usec)) {
+ a->tv_sec = 0;
+ a->tv_usec = 0;
+ return;
+ }
+
+ a->tv_sec -= b->tv_sec;
+ a->tv_usec -= b->tv_usec;
+ while ( a->tv_usec < 0 ) {
+ a->tv_sec--;
+ a->tv_usec += 1000000;
+ }
+}
+
+static unsigned int o2hb_elapsed_msecs(struct timeval *start,
+ struct timeval *end)
+{
+ struct timeval res = *end;
+
+ o2hb_tv_subtract(&res, start);
+
+ return res.tv_sec * 1000 + res.tv_usec / 1000;
+}
+
+/*
+ * we ride the region ref that the region dir holds. before the region
+ * dir is removed and drops it ref it will wait to tear down this
+ * thread.
+ */
+static int o2hb_thread(void *data)
+{
+ int i, ret;
+ struct o2hb_region *reg = data;
+ struct o2hb_bio_wait_ctxt write_wc;
+ struct timeval before_hb, after_hb;
+ unsigned int elapsed_msec;
+
+ mlog(ML_HEARTBEAT|ML_KTHREAD, "hb thread running\n");
+
+ set_user_nice(current, MIN_NICE);
+
+ /* Pin node */
+ o2nm_depend_this_node();
+
+ while (!kthread_should_stop() &&
+ !reg->hr_unclean_stop && !reg->hr_aborted_start) {
+ /* We track the time spent inside
+ * o2hb_do_disk_heartbeat so that we avoid more than
+ * hr_timeout_ms between disk writes. On busy systems
+ * this should result in a heartbeat which is less
+ * likely to time itself out. */
+ do_gettimeofday(&before_hb);
+
+ ret = o2hb_do_disk_heartbeat(reg);
+
+ do_gettimeofday(&after_hb);
+ elapsed_msec = o2hb_elapsed_msecs(&before_hb, &after_hb);
+
+ mlog(ML_HEARTBEAT,
+ "start = %lu.%lu, end = %lu.%lu, msec = %u, ret = %d\n",
+ before_hb.tv_sec, (unsigned long) before_hb.tv_usec,
+ after_hb.tv_sec, (unsigned long) after_hb.tv_usec,
+ elapsed_msec, ret);
+
+ if (!kthread_should_stop() &&
+ elapsed_msec < reg->hr_timeout_ms) {
+ /* the kthread api has blocked signals for us so no
+ * need to record the return value. */
+ msleep_interruptible(reg->hr_timeout_ms - elapsed_msec);
+ }
+ }
+
+ o2hb_disarm_write_timeout(reg);
+
+ /* unclean stop is only used in very bad situation */
+ for(i = 0; !reg->hr_unclean_stop && i < reg->hr_blocks; i++)
+ o2hb_shutdown_slot(®->hr_slots[i]);
+
+ /* Explicit down notification - avoid forcing the other nodes
+ * to timeout on this region when we could just as easily
+ * write a clear generation - thus indicating to them that
+ * this node has left this region.
+ */
+ if (!reg->hr_unclean_stop && !reg->hr_aborted_start) {
+ o2hb_prepare_block(reg, 0);
+ ret = o2hb_issue_node_write(reg, &write_wc);
+ if (ret == 0)
+ o2hb_wait_on_io(reg, &write_wc);
+ else
+ mlog_errno(ret);
+ }
+
+ /* Unpin node */
+ o2nm_undepend_this_node();
+
+ mlog(ML_HEARTBEAT|ML_KTHREAD, "o2hb thread exiting\n");
+
+ return 0;
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ struct o2hb_debug_buf *db = inode->i_private;
+ struct o2hb_region *reg;
+ unsigned long map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ unsigned long lts;
+ char *buf = NULL;
+ int i = -1;
+ int out = 0;
+
+ /* max_nodes should be the largest bitmap we pass here */
+ BUG_ON(sizeof(map) < db->db_size);
+
+ buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ goto bail;
+
+ switch (db->db_type) {
+ case O2HB_DB_TYPE_LIVENODES:
+ case O2HB_DB_TYPE_LIVEREGIONS:
+ case O2HB_DB_TYPE_QUORUMREGIONS:
+ case O2HB_DB_TYPE_FAILEDREGIONS:
+ spin_lock(&o2hb_live_lock);
+ memcpy(map, db->db_data, db->db_size);
+ spin_unlock(&o2hb_live_lock);
+ break;
+
+ case O2HB_DB_TYPE_REGION_LIVENODES:
+ spin_lock(&o2hb_live_lock);
+ reg = (struct o2hb_region *)db->db_data;
+ memcpy(map, reg->hr_live_node_bitmap, db->db_size);
+ spin_unlock(&o2hb_live_lock);
+ break;
+
+ case O2HB_DB_TYPE_REGION_NUMBER:
+ reg = (struct o2hb_region *)db->db_data;
+ out += snprintf(buf + out, PAGE_SIZE - out, "%d\n",
+ reg->hr_region_num);
+ goto done;
+
+ case O2HB_DB_TYPE_REGION_ELAPSED_TIME:
+ reg = (struct o2hb_region *)db->db_data;
+ lts = reg->hr_last_timeout_start;
+ /* If 0, it has never been set before */
+ if (lts)
+ lts = jiffies_to_msecs(jiffies - lts);
+ out += snprintf(buf + out, PAGE_SIZE - out, "%lu\n", lts);
+ goto done;
+
+ case O2HB_DB_TYPE_REGION_PINNED:
+ reg = (struct o2hb_region *)db->db_data;
+ out += snprintf(buf + out, PAGE_SIZE - out, "%u\n",
+ !!reg->hr_item_pinned);
+ goto done;
+
+ default:
+ goto done;
+ }
+
+ while ((i = find_next_bit(map, db->db_len, i + 1)) < db->db_len)
+ out += snprintf(buf + out, PAGE_SIZE - out, "%d ", i);
+ out += snprintf(buf + out, PAGE_SIZE - out, "\n");
+
+done:
+ i_size_write(inode, out);
+
+ file->private_data = buf;
+
+ return 0;
+bail:
+ return -ENOMEM;
+}
+
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
+ i_size_read(file->f_mapping->host));
+}
+#else
+static int o2hb_debug_open(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static int o2hb_debug_release(struct inode *inode, struct file *file)
+{
+ return 0;
+}
+static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
+ size_t nbytes, loff_t *ppos)
+{
+ return 0;
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static const struct file_operations o2hb_debug_fops = {
+ .open = o2hb_debug_open,
+ .release = o2hb_debug_release,
+ .read = o2hb_debug_read,
+ .llseek = generic_file_llseek,
+};
+
+void o2hb_exit(void)
+{
+ kfree(o2hb_db_livenodes);
+ kfree(o2hb_db_liveregions);
+ kfree(o2hb_db_quorumregions);
+ kfree(o2hb_db_failedregions);
+ debugfs_remove(o2hb_debug_failedregions);
+ debugfs_remove(o2hb_debug_quorumregions);
+ debugfs_remove(o2hb_debug_liveregions);
+ debugfs_remove(o2hb_debug_livenodes);
+ debugfs_remove(o2hb_debug_dir);
+}
+
+static struct dentry *o2hb_debug_create(const char *name, struct dentry *dir,
+ struct o2hb_debug_buf **db, int db_len,
+ int type, int size, int len, void *data)
+{
+ *db = kmalloc(db_len, GFP_KERNEL);
+ if (!*db)
+ return NULL;
+
+ (*db)->db_type = type;
+ (*db)->db_size = size;
+ (*db)->db_len = len;
+ (*db)->db_data = data;
+
+ return debugfs_create_file(name, S_IFREG|S_IRUSR, dir, *db,
+ &o2hb_debug_fops);
+}
+
+static int o2hb_debug_init(void)
+{
+ int ret = -ENOMEM;
+
+ o2hb_debug_dir = debugfs_create_dir(O2HB_DEBUG_DIR, NULL);
+ if (!o2hb_debug_dir) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ o2hb_debug_livenodes = o2hb_debug_create(O2HB_DEBUG_LIVENODES,
+ o2hb_debug_dir,
+ &o2hb_db_livenodes,
+ sizeof(*o2hb_db_livenodes),
+ O2HB_DB_TYPE_LIVENODES,
+ sizeof(o2hb_live_node_bitmap),
+ O2NM_MAX_NODES,
+ o2hb_live_node_bitmap);
+ if (!o2hb_debug_livenodes) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ o2hb_debug_liveregions = o2hb_debug_create(O2HB_DEBUG_LIVEREGIONS,
+ o2hb_debug_dir,
+ &o2hb_db_liveregions,
+ sizeof(*o2hb_db_liveregions),
+ O2HB_DB_TYPE_LIVEREGIONS,
+ sizeof(o2hb_live_region_bitmap),
+ O2NM_MAX_REGIONS,
+ o2hb_live_region_bitmap);
+ if (!o2hb_debug_liveregions) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ o2hb_debug_quorumregions =
+ o2hb_debug_create(O2HB_DEBUG_QUORUMREGIONS,
+ o2hb_debug_dir,
+ &o2hb_db_quorumregions,
+ sizeof(*o2hb_db_quorumregions),
+ O2HB_DB_TYPE_QUORUMREGIONS,
+ sizeof(o2hb_quorum_region_bitmap),
+ O2NM_MAX_REGIONS,
+ o2hb_quorum_region_bitmap);
+ if (!o2hb_debug_quorumregions) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ o2hb_debug_failedregions =
+ o2hb_debug_create(O2HB_DEBUG_FAILEDREGIONS,
+ o2hb_debug_dir,
+ &o2hb_db_failedregions,
+ sizeof(*o2hb_db_failedregions),
+ O2HB_DB_TYPE_FAILEDREGIONS,
+ sizeof(o2hb_failed_region_bitmap),
+ O2NM_MAX_REGIONS,
+ o2hb_failed_region_bitmap);
+ if (!o2hb_debug_failedregions) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ ret = 0;
+bail:
+ if (ret)
+ o2hb_exit();
+
+ return ret;
+}
+
+int o2hb_init(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(o2hb_callbacks); i++)
+ INIT_LIST_HEAD(&o2hb_callbacks[i].list);
+
+ for (i = 0; i < ARRAY_SIZE(o2hb_live_slots); i++)
+ INIT_LIST_HEAD(&o2hb_live_slots[i]);
+
+ INIT_LIST_HEAD(&o2hb_node_events);
+
+ memset(o2hb_live_node_bitmap, 0, sizeof(o2hb_live_node_bitmap));
+ memset(o2hb_region_bitmap, 0, sizeof(o2hb_region_bitmap));
+ memset(o2hb_live_region_bitmap, 0, sizeof(o2hb_live_region_bitmap));
+ memset(o2hb_quorum_region_bitmap, 0, sizeof(o2hb_quorum_region_bitmap));
+ memset(o2hb_failed_region_bitmap, 0, sizeof(o2hb_failed_region_bitmap));
+
+ o2hb_dependent_users = 0;
+
+ return o2hb_debug_init();
+}
+
+/* if we're already in a callback then we're already serialized by the sem */
+static void o2hb_fill_node_map_from_callback(unsigned long *map,
+ unsigned bytes)
+{
+ BUG_ON(bytes < (BITS_TO_LONGS(O2NM_MAX_NODES) * sizeof(unsigned long)));
+
+ memcpy(map, &o2hb_live_node_bitmap, bytes);
+}
+
+/*
+ * get a map of all nodes that are heartbeating in any regions
+ */
+void o2hb_fill_node_map(unsigned long *map, unsigned bytes)
+{
+ /* callers want to serialize this map and callbacks so that they
+ * can trust that they don't miss nodes coming to the party */
+ down_read(&o2hb_callback_sem);
+ spin_lock(&o2hb_live_lock);
+ o2hb_fill_node_map_from_callback(map, bytes);
+ spin_unlock(&o2hb_live_lock);
+ up_read(&o2hb_callback_sem);
+}
+EXPORT_SYMBOL_GPL(o2hb_fill_node_map);
+
+/*
+ * heartbeat configfs bits. The heartbeat set is a default set under
+ * the cluster set in nodemanager.c.
+ */
+
+static struct o2hb_region *to_o2hb_region(struct config_item *item)
+{
+ return item ? container_of(item, struct o2hb_region, hr_item) : NULL;
+}
+
+/* drop_item only drops its ref after killing the thread, nothing should
+ * be using the region anymore. this has to clean up any state that
+ * attributes might have built up. */
+static void o2hb_region_release(struct config_item *item)
+{
+ int i;
+ struct page *page;
+ struct o2hb_region *reg = to_o2hb_region(item);
+
+ mlog(ML_HEARTBEAT, "hb region release (%s)\n", reg->hr_dev_name);
+
+ kfree(reg->hr_tmp_block);
+
+ if (reg->hr_slot_data) {
+ for (i = 0; i < reg->hr_num_pages; i++) {
+ page = reg->hr_slot_data[i];
+ if (page)
+ __free_page(page);
+ }
+ kfree(reg->hr_slot_data);
+ }
+
+ if (reg->hr_bdev)
+ blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
+
+ kfree(reg->hr_slots);
+
+ kfree(reg->hr_db_regnum);
+ kfree(reg->hr_db_livenodes);
+ debugfs_remove(reg->hr_debug_livenodes);
+ debugfs_remove(reg->hr_debug_regnum);
+ debugfs_remove(reg->hr_debug_elapsed_time);
+ debugfs_remove(reg->hr_debug_pinned);
+ debugfs_remove(reg->hr_debug_dir);
+
+ spin_lock(&o2hb_live_lock);
+ list_del(®->hr_all_item);
+ spin_unlock(&o2hb_live_lock);
+
+ kfree(reg);
+}
+
+static int o2hb_read_block_input(struct o2hb_region *reg,
+ const char *page,
+ size_t count,
+ unsigned long *ret_bytes,
+ unsigned int *ret_bits)
+{
+ unsigned long bytes;
+ char *p = (char *)page;
+
+ bytes = simple_strtoul(p, &p, 0);
+ if (!p || (*p && (*p != '\n')))
+ return -EINVAL;
+
+ /* Heartbeat and fs min / max block sizes are the same. */
+ if (bytes > 4096 || bytes < 512)
+ return -ERANGE;
+ if (hweight16(bytes) != 1)
+ return -EINVAL;
+
+ if (ret_bytes)
+ *ret_bytes = bytes;
+ if (ret_bits)
+ *ret_bits = ffs(bytes) - 1;
+
+ return 0;
+}
+
+static ssize_t o2hb_region_block_bytes_read(struct o2hb_region *reg,
+ char *page)
+{
+ return sprintf(page, "%u\n", reg->hr_block_bytes);
+}
+
+static ssize_t o2hb_region_block_bytes_write(struct o2hb_region *reg,
+ const char *page,
+ size_t count)
+{
+ int status;
+ unsigned long block_bytes;
+ unsigned int block_bits;
+
+ if (reg->hr_bdev)
+ return -EINVAL;
+
+ status = o2hb_read_block_input(reg, page, count,
+ &block_bytes, &block_bits);
+ if (status)
+ return status;
+
+ reg->hr_block_bytes = (unsigned int)block_bytes;
+ reg->hr_block_bits = block_bits;
+
+ return count;
+}
+
+static ssize_t o2hb_region_start_block_read(struct o2hb_region *reg,
+ char *page)
+{
+ return sprintf(page, "%llu\n", reg->hr_start_block);
+}
+
+static ssize_t o2hb_region_start_block_write(struct o2hb_region *reg,
+ const char *page,
+ size_t count)
+{
+ unsigned long long tmp;
+ char *p = (char *)page;
+
+ if (reg->hr_bdev)
+ return -EINVAL;
+
+ tmp = simple_strtoull(p, &p, 0);
+ if (!p || (*p && (*p != '\n')))
+ return -EINVAL;
+
+ reg->hr_start_block = tmp;
+
+ return count;
+}
+
+static ssize_t o2hb_region_blocks_read(struct o2hb_region *reg,
+ char *page)
+{
+ return sprintf(page, "%d\n", reg->hr_blocks);
+}
+
+static ssize_t o2hb_region_blocks_write(struct o2hb_region *reg,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ char *p = (char *)page;
+
+ if (reg->hr_bdev)
+ return -EINVAL;
+
+ tmp = simple_strtoul(p, &p, 0);
+ if (!p || (*p && (*p != '\n')))
+ return -EINVAL;
+
+ if (tmp > O2NM_MAX_NODES || tmp == 0)
+ return -ERANGE;
+
+ reg->hr_blocks = (unsigned int)tmp;
+
+ return count;
+}
+
+static ssize_t o2hb_region_dev_read(struct o2hb_region *reg,
+ char *page)
+{
+ unsigned int ret = 0;
+
+ if (reg->hr_bdev)
+ ret = sprintf(page, "%s\n", reg->hr_dev_name);
+
+ return ret;
+}
+
+static void o2hb_init_region_params(struct o2hb_region *reg)
+{
+ reg->hr_slots_per_page = PAGE_CACHE_SIZE >> reg->hr_block_bits;
+ reg->hr_timeout_ms = O2HB_REGION_TIMEOUT_MS;
+
+ mlog(ML_HEARTBEAT, "hr_start_block = %llu, hr_blocks = %u\n",
+ reg->hr_start_block, reg->hr_blocks);
+ mlog(ML_HEARTBEAT, "hr_block_bytes = %u, hr_block_bits = %u\n",
+ reg->hr_block_bytes, reg->hr_block_bits);
+ mlog(ML_HEARTBEAT, "hr_timeout_ms = %u\n", reg->hr_timeout_ms);
+ mlog(ML_HEARTBEAT, "dead threshold = %u\n", o2hb_dead_threshold);
+}
+
+static int o2hb_map_slot_data(struct o2hb_region *reg)
+{
+ int i, j;
+ unsigned int last_slot;
+ unsigned int spp = reg->hr_slots_per_page;
+ struct page *page;
+ char *raw;
+ struct o2hb_disk_slot *slot;
+
+ reg->hr_tmp_block = kmalloc(reg->hr_block_bytes, GFP_KERNEL);
+ if (reg->hr_tmp_block == NULL) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ reg->hr_slots = kcalloc(reg->hr_blocks,
+ sizeof(struct o2hb_disk_slot), GFP_KERNEL);
+ if (reg->hr_slots == NULL) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ for(i = 0; i < reg->hr_blocks; i++) {
+ slot = ®->hr_slots[i];
+ slot->ds_node_num = i;
+ INIT_LIST_HEAD(&slot->ds_live_item);
+ slot->ds_raw_block = NULL;
+ }
+
+ reg->hr_num_pages = (reg->hr_blocks + spp - 1) / spp;
+ mlog(ML_HEARTBEAT, "Going to require %u pages to cover %u blocks "
+ "at %u blocks per page\n",
+ reg->hr_num_pages, reg->hr_blocks, spp);
+
+ reg->hr_slot_data = kcalloc(reg->hr_num_pages, sizeof(struct page *),
+ GFP_KERNEL);
+ if (!reg->hr_slot_data) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ for(i = 0; i < reg->hr_num_pages; i++) {
+ page = alloc_page(GFP_KERNEL);
+ if (!page) {
+ mlog_errno(-ENOMEM);
+ return -ENOMEM;
+ }
+
+ reg->hr_slot_data[i] = page;
+
+ last_slot = i * spp;
+ raw = page_address(page);
+ for (j = 0;
+ (j < spp) && ((j + last_slot) < reg->hr_blocks);
+ j++) {
+ BUG_ON((j + last_slot) >= reg->hr_blocks);
+
+ slot = ®->hr_slots[j + last_slot];
+ slot->ds_raw_block =
+ (struct o2hb_disk_heartbeat_block *) raw;
+
+ raw += reg->hr_block_bytes;
+ }
+ }
+
+ return 0;
+}
+
+/* Read in all the slots available and populate the tracking
+ * structures so that we can start with a baseline idea of what's
+ * there. */
+static int o2hb_populate_slot_data(struct o2hb_region *reg)
+{
+ int ret, i;
+ struct o2hb_disk_slot *slot;
+ struct o2hb_disk_heartbeat_block *hb_block;
+
+ ret = o2hb_read_slots(reg, reg->hr_blocks);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* We only want to get an idea of the values initially in each
+ * slot, so we do no verification - o2hb_check_slot will
+ * actually determine if each configured slot is valid and
+ * whether any values have changed. */
+ for(i = 0; i < reg->hr_blocks; i++) {
+ slot = ®->hr_slots[i];
+ hb_block = (struct o2hb_disk_heartbeat_block *) slot->ds_raw_block;
+
+ /* Only fill the values that o2hb_check_slot uses to
+ * determine changing slots */
+ slot->ds_last_time = le64_to_cpu(hb_block->hb_seq);
+ slot->ds_last_generation = le64_to_cpu(hb_block->hb_generation);
+ }
+
+out:
+ return ret;
+}
+
+/* this is acting as commit; we set up all of hr_bdev and hr_task or nothing */
+static ssize_t o2hb_region_dev_write(struct o2hb_region *reg,
+ const char *page,
+ size_t count)
+{
+ struct task_struct *hb_task;
+ long fd;
+ int sectsize;
+ char *p = (char *)page;
+ struct fd f;
+ struct inode *inode;
+ ssize_t ret = -EINVAL;
+ int live_threshold;
+
+ if (reg->hr_bdev)
+ goto out;
+
+ /* We can't heartbeat without having had our node number
+ * configured yet. */
+ if (o2nm_this_node() == O2NM_MAX_NODES)
+ goto out;
+
+ fd = simple_strtol(p, &p, 0);
+ if (!p || (*p && (*p != '\n')))
+ goto out;
+
+ if (fd < 0 || fd >= INT_MAX)
+ goto out;
+
+ f = fdget(fd);
+ if (f.file == NULL)
+ goto out;
+
+ if (reg->hr_blocks == 0 || reg->hr_start_block == 0 ||
+ reg->hr_block_bytes == 0)
+ goto out2;
+
+ inode = igrab(f.file->f_mapping->host);
+ if (inode == NULL)
+ goto out2;
+
+ if (!S_ISBLK(inode->i_mode))
+ goto out3;
+
+ reg->hr_bdev = I_BDEV(f.file->f_mapping->host);
+ ret = blkdev_get(reg->hr_bdev, FMODE_WRITE | FMODE_READ, NULL);
+ if (ret) {
+ reg->hr_bdev = NULL;
+ goto out3;
+ }
+ inode = NULL;
+
+ bdevname(reg->hr_bdev, reg->hr_dev_name);
+
+ sectsize = bdev_logical_block_size(reg->hr_bdev);
+ if (sectsize != reg->hr_block_bytes) {
+ mlog(ML_ERROR,
+ "blocksize %u incorrect for device, expected %d",
+ reg->hr_block_bytes, sectsize);
+ ret = -EINVAL;
+ goto out3;
+ }
+
+ o2hb_init_region_params(reg);
+
+ /* Generation of zero is invalid */
+ do {
+ get_random_bytes(®->hr_generation,
+ sizeof(reg->hr_generation));
+ } while (reg->hr_generation == 0);
+
+ ret = o2hb_map_slot_data(reg);
+ if (ret) {
+ mlog_errno(ret);
+ goto out3;
+ }
+
+ ret = o2hb_populate_slot_data(reg);
+ if (ret) {
+ mlog_errno(ret);
+ goto out3;
+ }
+
+ INIT_DELAYED_WORK(®->hr_write_timeout_work, o2hb_write_timeout);
+
+ /*
+ * A node is considered live after it has beat LIVE_THRESHOLD
+ * times. We're not steady until we've given them a chance
+ * _after_ our first read.
+ * The default threshold is bare minimum so as to limit the delay
+ * during mounts. For global heartbeat, the threshold doubled for the
+ * first region.
+ */
+ live_threshold = O2HB_LIVE_THRESHOLD;
+ if (o2hb_global_heartbeat_active()) {
+ spin_lock(&o2hb_live_lock);
+ if (bitmap_weight(o2hb_region_bitmap, O2NM_MAX_REGIONS) == 1)
+ live_threshold <<= 1;
+ spin_unlock(&o2hb_live_lock);
+ }
+ ++live_threshold;
+ atomic_set(®->hr_steady_iterations, live_threshold);
+ /* unsteady_iterations is double the steady_iterations */
+ atomic_set(®->hr_unsteady_iterations, (live_threshold << 1));
+
+ hb_task = kthread_run(o2hb_thread, reg, "o2hb-%s",
+ reg->hr_item.ci_name);
+ if (IS_ERR(hb_task)) {
+ ret = PTR_ERR(hb_task);
+ mlog_errno(ret);
+ goto out3;
+ }
+
+ spin_lock(&o2hb_live_lock);
+ reg->hr_task = hb_task;
+ spin_unlock(&o2hb_live_lock);
+
+ ret = wait_event_interruptible(o2hb_steady_queue,
+ atomic_read(®->hr_steady_iterations) == 0);
+ if (ret) {
+ atomic_set(®->hr_steady_iterations, 0);
+ reg->hr_aborted_start = 1;
+ }
+
+ if (reg->hr_aborted_start) {
+ ret = -EIO;
+ goto out3;
+ }
+
+ /* Ok, we were woken. Make sure it wasn't by drop_item() */
+ spin_lock(&o2hb_live_lock);
+ hb_task = reg->hr_task;
+ if (o2hb_global_heartbeat_active())
+ set_bit(reg->hr_region_num, o2hb_live_region_bitmap);
+ spin_unlock(&o2hb_live_lock);
+
+ if (hb_task)
+ ret = count;
+ else
+ ret = -EIO;
+
+ if (hb_task && o2hb_global_heartbeat_active())
+ printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%s)\n",
+ config_item_name(®->hr_item), reg->hr_dev_name);
+
+out3:
+ iput(inode);
+out2:
+ fdput(f);
+out:
+ if (ret < 0) {
+ if (reg->hr_bdev) {
+ blkdev_put(reg->hr_bdev, FMODE_READ|FMODE_WRITE);
+ reg->hr_bdev = NULL;
+ }
+ }
+ return ret;
+}
+
+static ssize_t o2hb_region_pid_read(struct o2hb_region *reg,
+ char *page)
+{
+ pid_t pid = 0;
+
+ spin_lock(&o2hb_live_lock);
+ if (reg->hr_task)
+ pid = task_pid_nr(reg->hr_task);
+ spin_unlock(&o2hb_live_lock);
+
+ if (!pid)
+ return 0;
+
+ return sprintf(page, "%u\n", pid);
+}
+
+struct o2hb_region_attribute {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct o2hb_region *, char *);
+ ssize_t (*store)(struct o2hb_region *, const char *, size_t);
+};
+
+static struct o2hb_region_attribute o2hb_region_attr_block_bytes = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "block_bytes",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_region_block_bytes_read,
+ .store = o2hb_region_block_bytes_write,
+};
+
+static struct o2hb_region_attribute o2hb_region_attr_start_block = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "start_block",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_region_start_block_read,
+ .store = o2hb_region_start_block_write,
+};
+
+static struct o2hb_region_attribute o2hb_region_attr_blocks = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "blocks",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_region_blocks_read,
+ .store = o2hb_region_blocks_write,
+};
+
+static struct o2hb_region_attribute o2hb_region_attr_dev = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "dev",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_region_dev_read,
+ .store = o2hb_region_dev_write,
+};
+
+static struct o2hb_region_attribute o2hb_region_attr_pid = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "pid",
+ .ca_mode = S_IRUGO | S_IRUSR },
+ .show = o2hb_region_pid_read,
+};
+
+static struct configfs_attribute *o2hb_region_attrs[] = {
+ &o2hb_region_attr_block_bytes.attr,
+ &o2hb_region_attr_start_block.attr,
+ &o2hb_region_attr_blocks.attr,
+ &o2hb_region_attr_dev.attr,
+ &o2hb_region_attr_pid.attr,
+ NULL,
+};
+
+static ssize_t o2hb_region_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *page)
+{
+ struct o2hb_region *reg = to_o2hb_region(item);
+ struct o2hb_region_attribute *o2hb_region_attr =
+ container_of(attr, struct o2hb_region_attribute, attr);
+ ssize_t ret = 0;
+
+ if (o2hb_region_attr->show)
+ ret = o2hb_region_attr->show(reg, page);
+ return ret;
+}
+
+static ssize_t o2hb_region_store(struct config_item *item,
+ struct configfs_attribute *attr,
+ const char *page, size_t count)
+{
+ struct o2hb_region *reg = to_o2hb_region(item);
+ struct o2hb_region_attribute *o2hb_region_attr =
+ container_of(attr, struct o2hb_region_attribute, attr);
+ ssize_t ret = -EINVAL;
+
+ if (o2hb_region_attr->store)
+ ret = o2hb_region_attr->store(reg, page, count);
+ return ret;
+}
+
+static struct configfs_item_operations o2hb_region_item_ops = {
+ .release = o2hb_region_release,
+ .show_attribute = o2hb_region_show,
+ .store_attribute = o2hb_region_store,
+};
+
+static struct config_item_type o2hb_region_type = {
+ .ct_item_ops = &o2hb_region_item_ops,
+ .ct_attrs = o2hb_region_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+/* heartbeat set */
+
+struct o2hb_heartbeat_group {
+ struct config_group hs_group;
+ /* some stuff? */
+};
+
+static struct o2hb_heartbeat_group *to_o2hb_heartbeat_group(struct config_group *group)
+{
+ return group ?
+ container_of(group, struct o2hb_heartbeat_group, hs_group)
+ : NULL;
+}
+
+static int o2hb_debug_region_init(struct o2hb_region *reg, struct dentry *dir)
+{
+ int ret = -ENOMEM;
+
+ reg->hr_debug_dir =
+ debugfs_create_dir(config_item_name(®->hr_item), dir);
+ if (!reg->hr_debug_dir) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ reg->hr_debug_livenodes =
+ o2hb_debug_create(O2HB_DEBUG_LIVENODES,
+ reg->hr_debug_dir,
+ &(reg->hr_db_livenodes),
+ sizeof(*(reg->hr_db_livenodes)),
+ O2HB_DB_TYPE_REGION_LIVENODES,
+ sizeof(reg->hr_live_node_bitmap),
+ O2NM_MAX_NODES, reg);
+ if (!reg->hr_debug_livenodes) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ reg->hr_debug_regnum =
+ o2hb_debug_create(O2HB_DEBUG_REGION_NUMBER,
+ reg->hr_debug_dir,
+ &(reg->hr_db_regnum),
+ sizeof(*(reg->hr_db_regnum)),
+ O2HB_DB_TYPE_REGION_NUMBER,
+ 0, O2NM_MAX_NODES, reg);
+ if (!reg->hr_debug_regnum) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ reg->hr_debug_elapsed_time =
+ o2hb_debug_create(O2HB_DEBUG_REGION_ELAPSED_TIME,
+ reg->hr_debug_dir,
+ &(reg->hr_db_elapsed_time),
+ sizeof(*(reg->hr_db_elapsed_time)),
+ O2HB_DB_TYPE_REGION_ELAPSED_TIME,
+ 0, 0, reg);
+ if (!reg->hr_debug_elapsed_time) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ reg->hr_debug_pinned =
+ o2hb_debug_create(O2HB_DEBUG_REGION_PINNED,
+ reg->hr_debug_dir,
+ &(reg->hr_db_pinned),
+ sizeof(*(reg->hr_db_pinned)),
+ O2HB_DB_TYPE_REGION_PINNED,
+ 0, 0, reg);
+ if (!reg->hr_debug_pinned) {
+ mlog_errno(ret);
+ goto bail;
+ }
+
+ ret = 0;
+bail:
+ return ret;
+}
+
+static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *group,
+ const char *name)
+{
+ struct o2hb_region *reg = NULL;
+ int ret;
+
+ reg = kzalloc(sizeof(struct o2hb_region), GFP_KERNEL);
+ if (reg == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ if (strlen(name) > O2HB_MAX_REGION_NAME_LEN) {
+ ret = -ENAMETOOLONG;
+ goto free;
+ }
+
+ spin_lock(&o2hb_live_lock);
+ reg->hr_region_num = 0;
+ if (o2hb_global_heartbeat_active()) {
+ reg->hr_region_num = find_first_zero_bit(o2hb_region_bitmap,
+ O2NM_MAX_REGIONS);
+ if (reg->hr_region_num >= O2NM_MAX_REGIONS) {
+ spin_unlock(&o2hb_live_lock);
+ ret = -EFBIG;
+ goto free;
+ }
+ set_bit(reg->hr_region_num, o2hb_region_bitmap);
+ }
+ list_add_tail(®->hr_all_item, &o2hb_all_regions);
+ spin_unlock(&o2hb_live_lock);
+
+ config_item_init_type_name(®->hr_item, name, &o2hb_region_type);
+
+ ret = o2hb_debug_region_init(reg, o2hb_debug_dir);
+ if (ret) {
+ config_item_put(®->hr_item);
+ goto free;
+ }
+
+ return ®->hr_item;
+free:
+ kfree(reg);
+ return ERR_PTR(ret);
+}
+
+static void o2hb_heartbeat_group_drop_item(struct config_group *group,
+ struct config_item *item)
+{
+ struct task_struct *hb_task;
+ struct o2hb_region *reg = to_o2hb_region(item);
+ int quorum_region = 0;
+
+ /* stop the thread when the user removes the region dir */
+ spin_lock(&o2hb_live_lock);
+ hb_task = reg->hr_task;
+ reg->hr_task = NULL;
+ reg->hr_item_dropped = 1;
+ spin_unlock(&o2hb_live_lock);
+
+ if (hb_task)
+ kthread_stop(hb_task);
+
+ if (o2hb_global_heartbeat_active()) {
+ spin_lock(&o2hb_live_lock);
+ clear_bit(reg->hr_region_num, o2hb_region_bitmap);
+ clear_bit(reg->hr_region_num, o2hb_live_region_bitmap);
+ if (test_bit(reg->hr_region_num, o2hb_quorum_region_bitmap))
+ quorum_region = 1;
+ clear_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
+ spin_unlock(&o2hb_live_lock);
+ printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%s)\n",
+ ((atomic_read(®->hr_steady_iterations) == 0) ?
+ "stopped" : "start aborted"), config_item_name(item),
+ reg->hr_dev_name);
+ }
+
+ /*
+ * If we're racing a dev_write(), we need to wake them. They will
+ * check reg->hr_task
+ */
+ if (atomic_read(®->hr_steady_iterations) != 0) {
+ reg->hr_aborted_start = 1;
+ atomic_set(®->hr_steady_iterations, 0);
+ wake_up(&o2hb_steady_queue);
+ }
+
+ config_item_put(item);
+
+ if (!o2hb_global_heartbeat_active() || !quorum_region)
+ return;
+
+ /*
+ * If global heartbeat active and there are dependent users,
+ * pin all regions if quorum region count <= CUT_OFF
+ */
+ spin_lock(&o2hb_live_lock);
+
+ if (!o2hb_dependent_users)
+ goto unlock;
+
+ if (bitmap_weight(o2hb_quorum_region_bitmap,
+ O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
+ o2hb_region_pin(NULL);
+
+unlock:
+ spin_unlock(&o2hb_live_lock);
+}
+
+struct o2hb_heartbeat_group_attribute {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct o2hb_heartbeat_group *, char *);
+ ssize_t (*store)(struct o2hb_heartbeat_group *, const char *, size_t);
+};
+
+static ssize_t o2hb_heartbeat_group_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *page)
+{
+ struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item));
+ struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr =
+ container_of(attr, struct o2hb_heartbeat_group_attribute, attr);
+ ssize_t ret = 0;
+
+ if (o2hb_heartbeat_group_attr->show)
+ ret = o2hb_heartbeat_group_attr->show(reg, page);
+ return ret;
+}
+
+static ssize_t o2hb_heartbeat_group_store(struct config_item *item,
+ struct configfs_attribute *attr,
+ const char *page, size_t count)
+{
+ struct o2hb_heartbeat_group *reg = to_o2hb_heartbeat_group(to_config_group(item));
+ struct o2hb_heartbeat_group_attribute *o2hb_heartbeat_group_attr =
+ container_of(attr, struct o2hb_heartbeat_group_attribute, attr);
+ ssize_t ret = -EINVAL;
+
+ if (o2hb_heartbeat_group_attr->store)
+ ret = o2hb_heartbeat_group_attr->store(reg, page, count);
+ return ret;
+}
+
+static ssize_t o2hb_heartbeat_group_threshold_show(struct o2hb_heartbeat_group *group,
+ char *page)
+{
+ return sprintf(page, "%u\n", o2hb_dead_threshold);
+}
+
+static ssize_t o2hb_heartbeat_group_threshold_store(struct o2hb_heartbeat_group *group,
+ const char *page,
+ size_t count)
+{
+ unsigned long tmp;
+ char *p = (char *)page;
+
+ tmp = simple_strtoul(p, &p, 10);
+ if (!p || (*p && (*p != '\n')))
+ return -EINVAL;
+
+ /* this will validate ranges for us. */
+ o2hb_dead_threshold_set((unsigned int) tmp);
+
+ return count;
+}
+
+static
+ssize_t o2hb_heartbeat_group_mode_show(struct o2hb_heartbeat_group *group,
+ char *page)
+{
+ return sprintf(page, "%s\n",
+ o2hb_heartbeat_mode_desc[o2hb_heartbeat_mode]);
+}
+
+static
+ssize_t o2hb_heartbeat_group_mode_store(struct o2hb_heartbeat_group *group,
+ const char *page, size_t count)
+{
+ unsigned int i;
+ int ret;
+ size_t len;
+
+ len = (page[count - 1] == '\n') ? count - 1 : count;
+ if (!len)
+ return -EINVAL;
+
+ for (i = 0; i < O2HB_HEARTBEAT_NUM_MODES; ++i) {
+ if (strncasecmp(page, o2hb_heartbeat_mode_desc[i], len))
+ continue;
+
+ ret = o2hb_global_heartbeat_mode_set(i);
+ if (!ret)
+ printk(KERN_NOTICE "o2hb: Heartbeat mode set to %s\n",
+ o2hb_heartbeat_mode_desc[i]);
+ return count;
+ }
+
+ return -EINVAL;
+
+}
+
+static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_threshold = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "dead_threshold",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_heartbeat_group_threshold_show,
+ .store = o2hb_heartbeat_group_threshold_store,
+};
+
+static struct o2hb_heartbeat_group_attribute o2hb_heartbeat_group_attr_mode = {
+ .attr = { .ca_owner = THIS_MODULE,
+ .ca_name = "mode",
+ .ca_mode = S_IRUGO | S_IWUSR },
+ .show = o2hb_heartbeat_group_mode_show,
+ .store = o2hb_heartbeat_group_mode_store,
+};
+
+static struct configfs_attribute *o2hb_heartbeat_group_attrs[] = {
+ &o2hb_heartbeat_group_attr_threshold.attr,
+ &o2hb_heartbeat_group_attr_mode.attr,
+ NULL,
+};
+
+static struct configfs_item_operations o2hb_heartbeat_group_item_ops = {
+ .show_attribute = o2hb_heartbeat_group_show,
+ .store_attribute = o2hb_heartbeat_group_store,
+};
+
+static struct configfs_group_operations o2hb_heartbeat_group_group_ops = {
+ .make_item = o2hb_heartbeat_group_make_item,
+ .drop_item = o2hb_heartbeat_group_drop_item,
+};
+
+static struct config_item_type o2hb_heartbeat_group_type = {
+ .ct_group_ops = &o2hb_heartbeat_group_group_ops,
+ .ct_item_ops = &o2hb_heartbeat_group_item_ops,
+ .ct_attrs = o2hb_heartbeat_group_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+/* this is just here to avoid touching group in heartbeat.h which the
+ * entire damn world #includes */
+struct config_group *o2hb_alloc_hb_set(void)
+{
+ struct o2hb_heartbeat_group *hs = NULL;
+ struct config_group *ret = NULL;
+
+ hs = kzalloc(sizeof(struct o2hb_heartbeat_group), GFP_KERNEL);
+ if (hs == NULL)
+ goto out;
+
+ config_group_init_type_name(&hs->hs_group, "heartbeat",
+ &o2hb_heartbeat_group_type);
+
+ ret = &hs->hs_group;
+out:
+ if (ret == NULL)
+ kfree(hs);
+ return ret;
+}
+
+void o2hb_free_hb_set(struct config_group *group)
+{
+ struct o2hb_heartbeat_group *hs = to_o2hb_heartbeat_group(group);
+ kfree(hs);
+}
+
+/* hb callback registration and issuing */
+
+static struct o2hb_callback *hbcall_from_type(enum o2hb_callback_type type)
+{
+ if (type == O2HB_NUM_CB)
+ return ERR_PTR(-EINVAL);
+
+ return &o2hb_callbacks[type];
+}
+
+void o2hb_setup_callback(struct o2hb_callback_func *hc,
+ enum o2hb_callback_type type,
+ o2hb_cb_func *func,
+ void *data,
+ int priority)
+{
+ INIT_LIST_HEAD(&hc->hc_item);
+ hc->hc_func = func;
+ hc->hc_data = data;
+ hc->hc_priority = priority;
+ hc->hc_type = type;
+ hc->hc_magic = O2HB_CB_MAGIC;
+}
+EXPORT_SYMBOL_GPL(o2hb_setup_callback);
+
+/*
+ * In local heartbeat mode, region_uuid passed matches the dlm domain name.
+ * In global heartbeat mode, region_uuid passed is NULL.
+ *
+ * In local, we only pin the matching region. In global we pin all the active
+ * regions.
+ */
+static int o2hb_region_pin(const char *region_uuid)
+{
+ int ret = 0, found = 0;
+ struct o2hb_region *reg;
+ char *uuid;
+
+ assert_spin_locked(&o2hb_live_lock);
+
+ list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
+ if (reg->hr_item_dropped)
+ continue;
+
+ uuid = config_item_name(®->hr_item);
+
+ /* local heartbeat */
+ if (region_uuid) {
+ if (strcmp(region_uuid, uuid))
+ continue;
+ found = 1;
+ }
+
+ if (reg->hr_item_pinned || reg->hr_item_dropped)
+ goto skip_pin;
+
+ /* Ignore ENOENT only for local hb (userdlm domain) */
+ ret = o2nm_depend_item(®->hr_item);
+ if (!ret) {
+ mlog(ML_CLUSTER, "Pin region %s\n", uuid);
+ reg->hr_item_pinned = 1;
+ } else {
+ if (ret == -ENOENT && found)
+ ret = 0;
+ else {
+ mlog(ML_ERROR, "Pin region %s fails with %d\n",
+ uuid, ret);
+ break;
+ }
+ }
+skip_pin:
+ if (found)
+ break;
+ }
+
+ return ret;
+}
+
+/*
+ * In local heartbeat mode, region_uuid passed matches the dlm domain name.
+ * In global heartbeat mode, region_uuid passed is NULL.
+ *
+ * In local, we only unpin the matching region. In global we unpin all the
+ * active regions.
+ */
+static void o2hb_region_unpin(const char *region_uuid)
+{
+ struct o2hb_region *reg;
+ char *uuid;
+ int found = 0;
+
+ assert_spin_locked(&o2hb_live_lock);
+
+ list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
+ if (reg->hr_item_dropped)
+ continue;
+
+ uuid = config_item_name(®->hr_item);
+ if (region_uuid) {
+ if (strcmp(region_uuid, uuid))
+ continue;
+ found = 1;
+ }
+
+ if (reg->hr_item_pinned) {
+ mlog(ML_CLUSTER, "Unpin region %s\n", uuid);
+ o2nm_undepend_item(®->hr_item);
+ reg->hr_item_pinned = 0;
+ }
+ if (found)
+ break;
+ }
+}
+
+static int o2hb_region_inc_user(const char *region_uuid)
+{
+ int ret = 0;
+
+ spin_lock(&o2hb_live_lock);
+
+ /* local heartbeat */
+ if (!o2hb_global_heartbeat_active()) {
+ ret = o2hb_region_pin(region_uuid);
+ goto unlock;
+ }
+
+ /*
+ * if global heartbeat active and this is the first dependent user,
+ * pin all regions if quorum region count <= CUT_OFF
+ */
+ o2hb_dependent_users++;
+ if (o2hb_dependent_users > 1)
+ goto unlock;
+
+ if (bitmap_weight(o2hb_quorum_region_bitmap,
+ O2NM_MAX_REGIONS) <= O2HB_PIN_CUT_OFF)
+ ret = o2hb_region_pin(NULL);
+
+unlock:
+ spin_unlock(&o2hb_live_lock);
+ return ret;
+}
+
+void o2hb_region_dec_user(const char *region_uuid)
+{
+ spin_lock(&o2hb_live_lock);
+
+ /* local heartbeat */
+ if (!o2hb_global_heartbeat_active()) {
+ o2hb_region_unpin(region_uuid);
+ goto unlock;
+ }
+
+ /*
+ * if global heartbeat active and there are no dependent users,
+ * unpin all quorum regions
+ */
+ o2hb_dependent_users--;
+ if (!o2hb_dependent_users)
+ o2hb_region_unpin(NULL);
+
+unlock:
+ spin_unlock(&o2hb_live_lock);
+}
+
+int o2hb_register_callback(const char *region_uuid,
+ struct o2hb_callback_func *hc)
+{
+ struct o2hb_callback_func *f;
+ struct o2hb_callback *hbcall;
+ int ret;
+
+ BUG_ON(hc->hc_magic != O2HB_CB_MAGIC);
+ BUG_ON(!list_empty(&hc->hc_item));
+
+ hbcall = hbcall_from_type(hc->hc_type);
+ if (IS_ERR(hbcall)) {
+ ret = PTR_ERR(hbcall);
+ goto out;
+ }
+
+ if (region_uuid) {
+ ret = o2hb_region_inc_user(region_uuid);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ down_write(&o2hb_callback_sem);
+
+ list_for_each_entry(f, &hbcall->list, hc_item) {
+ if (hc->hc_priority < f->hc_priority) {
+ list_add_tail(&hc->hc_item, &f->hc_item);
+ break;
+ }
+ }
+ if (list_empty(&hc->hc_item))
+ list_add_tail(&hc->hc_item, &hbcall->list);
+
+ up_write(&o2hb_callback_sem);
+ ret = 0;
+out:
+ mlog(ML_CLUSTER, "returning %d on behalf of %p for funcs %p\n",
+ ret, __builtin_return_address(0), hc);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(o2hb_register_callback);
+
+void o2hb_unregister_callback(const char *region_uuid,
+ struct o2hb_callback_func *hc)
+{
+ BUG_ON(hc->hc_magic != O2HB_CB_MAGIC);
+
+ mlog(ML_CLUSTER, "on behalf of %p for funcs %p\n",
+ __builtin_return_address(0), hc);
+
+ /* XXX Can this happen _with_ a region reference? */
+ if (list_empty(&hc->hc_item))
+ return;
+
+ if (region_uuid)
+ o2hb_region_dec_user(region_uuid);
+
+ down_write(&o2hb_callback_sem);
+
+ list_del_init(&hc->hc_item);
+
+ up_write(&o2hb_callback_sem);
+}
+EXPORT_SYMBOL_GPL(o2hb_unregister_callback);
+
+int o2hb_check_node_heartbeating(u8 node_num)
+{
+ unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+
+ o2hb_fill_node_map(testing_map, sizeof(testing_map));
+ if (!test_bit(node_num, testing_map)) {
+ mlog(ML_HEARTBEAT,
+ "node (%u) does not have heartbeating enabled.\n",
+ node_num);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating);
+
+int o2hb_check_node_heartbeating_no_sem(u8 node_num)
+{
+ unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+ unsigned long flags;
+
+ spin_lock_irqsave(&o2hb_live_lock, flags);
+ o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map));
+ spin_unlock_irqrestore(&o2hb_live_lock, flags);
+ if (!test_bit(node_num, testing_map)) {
+ mlog(ML_HEARTBEAT,
+ "node (%u) does not have heartbeating enabled.\n",
+ node_num);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_no_sem);
+
+int o2hb_check_node_heartbeating_from_callback(u8 node_num)
+{
+ unsigned long testing_map[BITS_TO_LONGS(O2NM_MAX_NODES)];
+
+ o2hb_fill_node_map_from_callback(testing_map, sizeof(testing_map));
+ if (!test_bit(node_num, testing_map)) {
+ mlog(ML_HEARTBEAT,
+ "node (%u) does not have heartbeating enabled.\n",
+ node_num);
+ return 0;
+ }
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(o2hb_check_node_heartbeating_from_callback);
+
+/* Makes sure our local node is configured with a node number, and is
+ * heartbeating. */
+int o2hb_check_local_node_heartbeating(void)
+{
+ u8 node_num;
+
+ /* if this node was set then we have networking */
+ node_num = o2nm_this_node();
+ if (node_num == O2NM_MAX_NODES) {
+ mlog(ML_HEARTBEAT, "this node has not been configured.\n");
+ return 0;
+ }
+
+ return o2hb_check_node_heartbeating(node_num);
+}
+EXPORT_SYMBOL_GPL(o2hb_check_local_node_heartbeating);
+
+/*
+ * this is just a hack until we get the plumbing which flips file systems
+ * read only and drops the hb ref instead of killing the node dead.
+ */
+void o2hb_stop_all_regions(void)
+{
+ struct o2hb_region *reg;
+
+ mlog(ML_ERROR, "stopping heartbeat on all active regions.\n");
+
+ spin_lock(&o2hb_live_lock);
+
+ list_for_each_entry(reg, &o2hb_all_regions, hr_all_item)
+ reg->hr_unclean_stop = 1;
+
+ spin_unlock(&o2hb_live_lock);
+}
+EXPORT_SYMBOL_GPL(o2hb_stop_all_regions);
+
+int o2hb_get_all_regions(char *region_uuids, u8 max_regions)
+{
+ struct o2hb_region *reg;
+ int numregs = 0;
+ char *p;
+
+ spin_lock(&o2hb_live_lock);
+
+ p = region_uuids;
+ list_for_each_entry(reg, &o2hb_all_regions, hr_all_item) {
+ if (reg->hr_item_dropped)
+ continue;
+
+ mlog(0, "Region: %s\n", config_item_name(®->hr_item));
+ if (numregs < max_regions) {
+ memcpy(p, config_item_name(®->hr_item),
+ O2HB_MAX_REGION_NAME_LEN);
+ p += O2HB_MAX_REGION_NAME_LEN;
+ }
+ numregs++;
+ }
+
+ spin_unlock(&o2hb_live_lock);
+
+ return numregs;
+}
+EXPORT_SYMBOL_GPL(o2hb_get_all_regions);
+
+int o2hb_global_heartbeat_active(void)
+{
+ return (o2hb_heartbeat_mode == O2HB_HEARTBEAT_GLOBAL);
+}
+EXPORT_SYMBOL(o2hb_global_heartbeat_active);
Code Review / kvmfornfv.git / blobdiff