mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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356b8103d4
It turns out that the might_sleep() call that commit660a6126f8
adds is triggering occasional data corruption in testing. We're not sure about the root cause yet, but since this commit was added as a debugging aid only, revert it for now. This reverts commit660a6126f8
. Fixes:660a6126f8
("gfs2: check context in gfs2_glock_put") Cc: stable@vger.kernel.org # v5.16+ Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2766 lines
72 KiB
C
2766 lines
72 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
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* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/buffer_head.h>
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#include <linux/delay.h>
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#include <linux/sort.h>
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#include <linux/hash.h>
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#include <linux/jhash.h>
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#include <linux/kallsyms.h>
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#include <linux/gfs2_ondisk.h>
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#include <linux/list.h>
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#include <linux/wait.h>
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#include <linux/module.h>
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#include <linux/uaccess.h>
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#include <linux/seq_file.h>
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#include <linux/debugfs.h>
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#include <linux/kthread.h>
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#include <linux/freezer.h>
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#include <linux/workqueue.h>
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#include <linux/jiffies.h>
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#include <linux/rcupdate.h>
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#include <linux/rculist_bl.h>
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#include <linux/bit_spinlock.h>
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#include <linux/percpu.h>
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#include <linux/list_sort.h>
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#include <linux/lockref.h>
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#include <linux/rhashtable.h>
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#include "gfs2.h"
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#include "incore.h"
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#include "glock.h"
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#include "glops.h"
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#include "inode.h"
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#include "lops.h"
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#include "meta_io.h"
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#include "quota.h"
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#include "super.h"
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#include "util.h"
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#include "bmap.h"
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#define CREATE_TRACE_POINTS
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#include "trace_gfs2.h"
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struct gfs2_glock_iter {
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struct gfs2_sbd *sdp; /* incore superblock */
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struct rhashtable_iter hti; /* rhashtable iterator */
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struct gfs2_glock *gl; /* current glock struct */
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loff_t last_pos; /* last position */
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};
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typedef void (*glock_examiner) (struct gfs2_glock * gl);
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static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target);
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static void __gfs2_glock_dq(struct gfs2_holder *gh);
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static struct dentry *gfs2_root;
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static struct workqueue_struct *glock_workqueue;
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struct workqueue_struct *gfs2_delete_workqueue;
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static LIST_HEAD(lru_list);
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static atomic_t lru_count = ATOMIC_INIT(0);
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static DEFINE_SPINLOCK(lru_lock);
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#define GFS2_GL_HASH_SHIFT 15
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#define GFS2_GL_HASH_SIZE BIT(GFS2_GL_HASH_SHIFT)
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static const struct rhashtable_params ht_parms = {
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.nelem_hint = GFS2_GL_HASH_SIZE * 3 / 4,
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.key_len = offsetofend(struct lm_lockname, ln_type),
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.key_offset = offsetof(struct gfs2_glock, gl_name),
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.head_offset = offsetof(struct gfs2_glock, gl_node),
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};
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static struct rhashtable gl_hash_table;
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#define GLOCK_WAIT_TABLE_BITS 12
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#define GLOCK_WAIT_TABLE_SIZE (1 << GLOCK_WAIT_TABLE_BITS)
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static wait_queue_head_t glock_wait_table[GLOCK_WAIT_TABLE_SIZE] __cacheline_aligned;
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struct wait_glock_queue {
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struct lm_lockname *name;
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wait_queue_entry_t wait;
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};
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static int glock_wake_function(wait_queue_entry_t *wait, unsigned int mode,
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int sync, void *key)
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{
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struct wait_glock_queue *wait_glock =
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container_of(wait, struct wait_glock_queue, wait);
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struct lm_lockname *wait_name = wait_glock->name;
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struct lm_lockname *wake_name = key;
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if (wake_name->ln_sbd != wait_name->ln_sbd ||
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wake_name->ln_number != wait_name->ln_number ||
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wake_name->ln_type != wait_name->ln_type)
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return 0;
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return autoremove_wake_function(wait, mode, sync, key);
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}
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static wait_queue_head_t *glock_waitqueue(struct lm_lockname *name)
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{
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u32 hash = jhash2((u32 *)name, ht_parms.key_len / 4, 0);
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return glock_wait_table + hash_32(hash, GLOCK_WAIT_TABLE_BITS);
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}
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/**
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* wake_up_glock - Wake up waiters on a glock
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* @gl: the glock
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*/
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static void wake_up_glock(struct gfs2_glock *gl)
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{
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wait_queue_head_t *wq = glock_waitqueue(&gl->gl_name);
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if (waitqueue_active(wq))
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__wake_up(wq, TASK_NORMAL, 1, &gl->gl_name);
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}
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static void gfs2_glock_dealloc(struct rcu_head *rcu)
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{
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struct gfs2_glock *gl = container_of(rcu, struct gfs2_glock, gl_rcu);
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kfree(gl->gl_lksb.sb_lvbptr);
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if (gl->gl_ops->go_flags & GLOF_ASPACE)
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kmem_cache_free(gfs2_glock_aspace_cachep, gl);
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else
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kmem_cache_free(gfs2_glock_cachep, gl);
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}
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/**
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* glock_blocked_by_withdraw - determine if we can still use a glock
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* @gl: the glock
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*
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* We need to allow some glocks to be enqueued, dequeued, promoted, and demoted
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* when we're withdrawn. For example, to maintain metadata integrity, we should
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* disallow the use of inode and rgrp glocks when withdrawn. Other glocks, like
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* iopen or the transaction glocks may be safely used because none of their
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* metadata goes through the journal. So in general, we should disallow all
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* glocks that are journaled, and allow all the others. One exception is:
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* we need to allow our active journal to be promoted and demoted so others
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* may recover it and we can reacquire it when they're done.
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*/
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static bool glock_blocked_by_withdraw(struct gfs2_glock *gl)
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{
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struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
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if (likely(!gfs2_withdrawn(sdp)))
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return false;
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if (gl->gl_ops->go_flags & GLOF_NONDISK)
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return false;
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if (!sdp->sd_jdesc ||
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gl->gl_name.ln_number == sdp->sd_jdesc->jd_no_addr)
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return false;
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return true;
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}
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void gfs2_glock_free(struct gfs2_glock *gl)
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{
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struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
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gfs2_glock_assert_withdraw(gl, atomic_read(&gl->gl_revokes) == 0);
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rhashtable_remove_fast(&gl_hash_table, &gl->gl_node, ht_parms);
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smp_mb();
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wake_up_glock(gl);
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call_rcu(&gl->gl_rcu, gfs2_glock_dealloc);
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if (atomic_dec_and_test(&sdp->sd_glock_disposal))
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wake_up(&sdp->sd_glock_wait);
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}
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/**
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* gfs2_glock_hold() - increment reference count on glock
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* @gl: The glock to hold
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*
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*/
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void gfs2_glock_hold(struct gfs2_glock *gl)
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{
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GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
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lockref_get(&gl->gl_lockref);
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}
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/**
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* demote_ok - Check to see if it's ok to unlock a glock
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* @gl: the glock
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*
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* Returns: 1 if it's ok
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*/
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static int demote_ok(const struct gfs2_glock *gl)
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{
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const struct gfs2_glock_operations *glops = gl->gl_ops;
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if (gl->gl_state == LM_ST_UNLOCKED)
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return 0;
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/*
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* Note that demote_ok is used for the lru process of disposing of
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* glocks. For this purpose, we don't care if the glock's holders
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* have the HIF_MAY_DEMOTE flag set or not. If someone is using
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* them, don't demote.
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*/
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if (!list_empty(&gl->gl_holders))
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return 0;
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if (glops->go_demote_ok)
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return glops->go_demote_ok(gl);
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return 1;
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}
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void gfs2_glock_add_to_lru(struct gfs2_glock *gl)
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{
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if (!(gl->gl_ops->go_flags & GLOF_LRU))
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return;
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spin_lock(&lru_lock);
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list_move_tail(&gl->gl_lru, &lru_list);
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if (!test_bit(GLF_LRU, &gl->gl_flags)) {
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set_bit(GLF_LRU, &gl->gl_flags);
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atomic_inc(&lru_count);
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}
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spin_unlock(&lru_lock);
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}
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static void gfs2_glock_remove_from_lru(struct gfs2_glock *gl)
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{
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if (!(gl->gl_ops->go_flags & GLOF_LRU))
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return;
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spin_lock(&lru_lock);
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if (test_bit(GLF_LRU, &gl->gl_flags)) {
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list_del_init(&gl->gl_lru);
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atomic_dec(&lru_count);
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clear_bit(GLF_LRU, &gl->gl_flags);
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}
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spin_unlock(&lru_lock);
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}
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/*
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* Enqueue the glock on the work queue. Passes one glock reference on to the
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* work queue.
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*/
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static void __gfs2_glock_queue_work(struct gfs2_glock *gl, unsigned long delay) {
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if (!queue_delayed_work(glock_workqueue, &gl->gl_work, delay)) {
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/*
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* We are holding the lockref spinlock, and the work was still
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* queued above. The queued work (glock_work_func) takes that
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* spinlock before dropping its glock reference(s), so it
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* cannot have dropped them in the meantime.
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*/
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GLOCK_BUG_ON(gl, gl->gl_lockref.count < 2);
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gl->gl_lockref.count--;
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}
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}
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static void gfs2_glock_queue_work(struct gfs2_glock *gl, unsigned long delay) {
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spin_lock(&gl->gl_lockref.lock);
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__gfs2_glock_queue_work(gl, delay);
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spin_unlock(&gl->gl_lockref.lock);
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}
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static void __gfs2_glock_put(struct gfs2_glock *gl)
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{
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struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
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struct address_space *mapping = gfs2_glock2aspace(gl);
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lockref_mark_dead(&gl->gl_lockref);
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gfs2_glock_remove_from_lru(gl);
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spin_unlock(&gl->gl_lockref.lock);
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GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders));
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if (mapping) {
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truncate_inode_pages_final(mapping);
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if (!gfs2_withdrawn(sdp))
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GLOCK_BUG_ON(gl, !mapping_empty(mapping));
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}
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trace_gfs2_glock_put(gl);
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sdp->sd_lockstruct.ls_ops->lm_put_lock(gl);
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}
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/*
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* Cause the glock to be put in work queue context.
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*/
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void gfs2_glock_queue_put(struct gfs2_glock *gl)
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{
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gfs2_glock_queue_work(gl, 0);
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}
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/**
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* gfs2_glock_put() - Decrement reference count on glock
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* @gl: The glock to put
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*
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*/
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void gfs2_glock_put(struct gfs2_glock *gl)
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{
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if (lockref_put_or_lock(&gl->gl_lockref))
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return;
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__gfs2_glock_put(gl);
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}
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/**
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* may_grant - check if it's ok to grant a new lock
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* @gl: The glock
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* @current_gh: One of the current holders of @gl
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* @gh: The lock request which we wish to grant
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*
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* With our current compatibility rules, if a glock has one or more active
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* holders (HIF_HOLDER flag set), any of those holders can be passed in as
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* @current_gh; they are all the same as far as compatibility with the new @gh
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* goes.
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*
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* Returns true if it's ok to grant the lock.
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*/
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static inline bool may_grant(struct gfs2_glock *gl,
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struct gfs2_holder *current_gh,
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struct gfs2_holder *gh)
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{
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if (current_gh) {
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GLOCK_BUG_ON(gl, !test_bit(HIF_HOLDER, ¤t_gh->gh_iflags));
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switch(current_gh->gh_state) {
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case LM_ST_EXCLUSIVE:
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/*
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* Here we make a special exception to grant holders
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* who agree to share the EX lock with other holders
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* who also have the bit set. If the original holder
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* has the LM_FLAG_NODE_SCOPE bit set, we grant more
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* holders with the bit set.
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*/
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return gh->gh_state == LM_ST_EXCLUSIVE &&
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(current_gh->gh_flags & LM_FLAG_NODE_SCOPE) &&
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(gh->gh_flags & LM_FLAG_NODE_SCOPE);
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case LM_ST_SHARED:
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case LM_ST_DEFERRED:
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return gh->gh_state == current_gh->gh_state;
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default:
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return false;
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}
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}
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if (gl->gl_state == gh->gh_state)
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return true;
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if (gh->gh_flags & GL_EXACT)
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return false;
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if (gl->gl_state == LM_ST_EXCLUSIVE) {
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return gh->gh_state == LM_ST_SHARED ||
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gh->gh_state == LM_ST_DEFERRED;
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}
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if (gh->gh_flags & LM_FLAG_ANY)
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return gl->gl_state != LM_ST_UNLOCKED;
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return false;
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}
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static void gfs2_holder_wake(struct gfs2_holder *gh)
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{
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clear_bit(HIF_WAIT, &gh->gh_iflags);
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smp_mb__after_atomic();
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wake_up_bit(&gh->gh_iflags, HIF_WAIT);
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if (gh->gh_flags & GL_ASYNC) {
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struct gfs2_sbd *sdp = gh->gh_gl->gl_name.ln_sbd;
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wake_up(&sdp->sd_async_glock_wait);
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}
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}
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/**
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* do_error - Something unexpected has happened during a lock request
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* @gl: The glock
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* @ret: The status from the DLM
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*/
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static void do_error(struct gfs2_glock *gl, const int ret)
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{
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struct gfs2_holder *gh, *tmp;
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list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
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if (!test_bit(HIF_WAIT, &gh->gh_iflags))
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continue;
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if (ret & LM_OUT_ERROR)
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gh->gh_error = -EIO;
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else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))
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gh->gh_error = GLR_TRYFAILED;
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else
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continue;
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list_del_init(&gh->gh_list);
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trace_gfs2_glock_queue(gh, 0);
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gfs2_holder_wake(gh);
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}
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}
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/**
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* demote_incompat_holders - demote incompatible demoteable holders
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* @gl: the glock we want to promote
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* @new_gh: the new holder to be promoted
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*/
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static void demote_incompat_holders(struct gfs2_glock *gl,
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struct gfs2_holder *new_gh)
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{
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struct gfs2_holder *gh, *tmp;
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/*
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* Demote incompatible holders before we make ourselves eligible.
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* (This holder may or may not allow auto-demoting, but we don't want
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* to demote the new holder before it's even granted.)
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*/
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list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
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/*
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* Since holders are at the front of the list, we stop when we
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* find the first non-holder.
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*/
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if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
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return;
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if (test_bit(HIF_MAY_DEMOTE, &gh->gh_iflags) &&
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!may_grant(gl, new_gh, gh)) {
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/*
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* We should not recurse into do_promote because
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* __gfs2_glock_dq only calls handle_callback,
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* gfs2_glock_add_to_lru and __gfs2_glock_queue_work.
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*/
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__gfs2_glock_dq(gh);
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}
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}
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}
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/**
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* find_first_holder - find the first "holder" gh
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* @gl: the glock
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*/
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static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl)
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{
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struct gfs2_holder *gh;
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if (!list_empty(&gl->gl_holders)) {
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gh = list_first_entry(&gl->gl_holders, struct gfs2_holder,
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gh_list);
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if (test_bit(HIF_HOLDER, &gh->gh_iflags))
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return gh;
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}
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return NULL;
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}
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/**
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* find_first_strong_holder - find the first non-demoteable holder
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* @gl: the glock
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*
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* Find the first holder that doesn't have the HIF_MAY_DEMOTE flag set.
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*/
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static inline struct gfs2_holder *
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find_first_strong_holder(struct gfs2_glock *gl)
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{
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struct gfs2_holder *gh;
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|
|
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
|
|
if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
|
|
return NULL;
|
|
if (!test_bit(HIF_MAY_DEMOTE, &gh->gh_iflags))
|
|
return gh;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* gfs2_instantiate - Call the glops instantiate function
|
|
* @gh: The glock holder
|
|
*
|
|
* Returns: 0 if instantiate was successful, 2 if type specific operation is
|
|
* underway, or error.
|
|
*/
|
|
int gfs2_instantiate(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
int ret;
|
|
|
|
again:
|
|
if (!test_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags))
|
|
return 0;
|
|
|
|
/*
|
|
* Since we unlock the lockref lock, we set a flag to indicate
|
|
* instantiate is in progress.
|
|
*/
|
|
if (test_and_set_bit(GLF_INSTANTIATE_IN_PROG, &gl->gl_flags)) {
|
|
wait_on_bit(&gl->gl_flags, GLF_INSTANTIATE_IN_PROG,
|
|
TASK_UNINTERRUPTIBLE);
|
|
/*
|
|
* Here we just waited for a different instantiate to finish.
|
|
* But that may not have been successful, as when a process
|
|
* locks an inode glock _before_ it has an actual inode to
|
|
* instantiate into. So we check again. This process might
|
|
* have an inode to instantiate, so might be successful.
|
|
*/
|
|
goto again;
|
|
}
|
|
|
|
ret = glops->go_instantiate(gh);
|
|
if (!ret)
|
|
clear_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags);
|
|
clear_and_wake_up_bit(GLF_INSTANTIATE_IN_PROG, &gl->gl_flags);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* do_promote - promote as many requests as possible on the current queue
|
|
* @gl: The glock
|
|
*
|
|
* Returns: 1 if there is a blocked holder at the head of the list, or 2
|
|
* if a type specific operation is underway.
|
|
*/
|
|
|
|
static int do_promote(struct gfs2_glock *gl)
|
|
__releases(&gl->gl_lockref.lock)
|
|
__acquires(&gl->gl_lockref.lock)
|
|
{
|
|
struct gfs2_holder *gh, *tmp, *first_gh;
|
|
bool incompat_holders_demoted = false;
|
|
bool lock_released;
|
|
int ret;
|
|
|
|
restart:
|
|
first_gh = find_first_strong_holder(gl);
|
|
list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) {
|
|
lock_released = false;
|
|
if (test_bit(HIF_HOLDER, &gh->gh_iflags))
|
|
continue;
|
|
if (!may_grant(gl, first_gh, gh)) {
|
|
/*
|
|
* If we get here, it means we may not grant this holder for
|
|
* some reason. If this holder is the head of the list, it
|
|
* means we have a blocked holder at the head, so return 1.
|
|
*/
|
|
if (gh->gh_list.prev == &gl->gl_holders)
|
|
return 1;
|
|
do_error(gl, 0);
|
|
break;
|
|
}
|
|
if (!incompat_holders_demoted) {
|
|
demote_incompat_holders(gl, first_gh);
|
|
incompat_holders_demoted = true;
|
|
first_gh = gh;
|
|
}
|
|
if (test_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags) &&
|
|
!(gh->gh_flags & GL_SKIP) && gl->gl_ops->go_instantiate) {
|
|
lock_released = true;
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
ret = gfs2_instantiate(gh);
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
if (ret) {
|
|
if (ret == 1)
|
|
return 2;
|
|
gh->gh_error = ret;
|
|
list_del_init(&gh->gh_list);
|
|
trace_gfs2_glock_queue(gh, 0);
|
|
gfs2_holder_wake(gh);
|
|
goto restart;
|
|
}
|
|
}
|
|
set_bit(HIF_HOLDER, &gh->gh_iflags);
|
|
trace_gfs2_promote(gh);
|
|
gfs2_holder_wake(gh);
|
|
/*
|
|
* If we released the gl_lockref.lock the holders list may have
|
|
* changed. For that reason, we start again at the start of
|
|
* the holders queue.
|
|
*/
|
|
if (lock_released)
|
|
goto restart;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* find_first_waiter - find the first gh that's waiting for the glock
|
|
* @gl: the glock
|
|
*/
|
|
|
|
static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_holder *gh;
|
|
|
|
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
|
|
if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
|
|
return gh;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* state_change - record that the glock is now in a different state
|
|
* @gl: the glock
|
|
* @new_state: the new state
|
|
*/
|
|
|
|
static void state_change(struct gfs2_glock *gl, unsigned int new_state)
|
|
{
|
|
int held1, held2;
|
|
|
|
held1 = (gl->gl_state != LM_ST_UNLOCKED);
|
|
held2 = (new_state != LM_ST_UNLOCKED);
|
|
|
|
if (held1 != held2) {
|
|
GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref));
|
|
if (held2)
|
|
gl->gl_lockref.count++;
|
|
else
|
|
gl->gl_lockref.count--;
|
|
}
|
|
if (new_state != gl->gl_target)
|
|
/* shorten our minimum hold time */
|
|
gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR,
|
|
GL_GLOCK_MIN_HOLD);
|
|
gl->gl_state = new_state;
|
|
gl->gl_tchange = jiffies;
|
|
}
|
|
|
|
static void gfs2_set_demote(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
|
|
set_bit(GLF_DEMOTE, &gl->gl_flags);
|
|
smp_mb();
|
|
wake_up(&sdp->sd_async_glock_wait);
|
|
}
|
|
|
|
static void gfs2_demote_wake(struct gfs2_glock *gl)
|
|
{
|
|
gl->gl_demote_state = LM_ST_EXCLUSIVE;
|
|
clear_bit(GLF_DEMOTE, &gl->gl_flags);
|
|
smp_mb__after_atomic();
|
|
wake_up_bit(&gl->gl_flags, GLF_DEMOTE);
|
|
}
|
|
|
|
/**
|
|
* finish_xmote - The DLM has replied to one of our lock requests
|
|
* @gl: The glock
|
|
* @ret: The status from the DLM
|
|
*
|
|
*/
|
|
|
|
static void finish_xmote(struct gfs2_glock *gl, unsigned int ret)
|
|
{
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
struct gfs2_holder *gh;
|
|
unsigned state = ret & LM_OUT_ST_MASK;
|
|
int rv;
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
trace_gfs2_glock_state_change(gl, state);
|
|
state_change(gl, state);
|
|
gh = find_first_waiter(gl);
|
|
|
|
/* Demote to UN request arrived during demote to SH or DF */
|
|
if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) &&
|
|
state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED)
|
|
gl->gl_target = LM_ST_UNLOCKED;
|
|
|
|
/* Check for state != intended state */
|
|
if (unlikely(state != gl->gl_target)) {
|
|
if (gh && !test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags)) {
|
|
/* move to back of queue and try next entry */
|
|
if (ret & LM_OUT_CANCELED) {
|
|
if ((gh->gh_flags & LM_FLAG_PRIORITY) == 0)
|
|
list_move_tail(&gh->gh_list, &gl->gl_holders);
|
|
gh = find_first_waiter(gl);
|
|
gl->gl_target = gh->gh_state;
|
|
goto retry;
|
|
}
|
|
/* Some error or failed "try lock" - report it */
|
|
if ((ret & LM_OUT_ERROR) ||
|
|
(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
|
|
gl->gl_target = gl->gl_state;
|
|
do_error(gl, ret);
|
|
goto out;
|
|
}
|
|
}
|
|
switch(state) {
|
|
/* Unlocked due to conversion deadlock, try again */
|
|
case LM_ST_UNLOCKED:
|
|
retry:
|
|
do_xmote(gl, gh, gl->gl_target);
|
|
break;
|
|
/* Conversion fails, unlock and try again */
|
|
case LM_ST_SHARED:
|
|
case LM_ST_DEFERRED:
|
|
do_xmote(gl, gh, LM_ST_UNLOCKED);
|
|
break;
|
|
default: /* Everything else */
|
|
fs_err(gl->gl_name.ln_sbd, "wanted %u got %u\n",
|
|
gl->gl_target, state);
|
|
GLOCK_BUG_ON(gl, 1);
|
|
}
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
return;
|
|
}
|
|
|
|
/* Fast path - we got what we asked for */
|
|
if (test_and_clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags))
|
|
gfs2_demote_wake(gl);
|
|
if (state != LM_ST_UNLOCKED) {
|
|
if (glops->go_xmote_bh) {
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
rv = glops->go_xmote_bh(gl);
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
if (rv) {
|
|
do_error(gl, rv);
|
|
goto out;
|
|
}
|
|
}
|
|
rv = do_promote(gl);
|
|
if (rv == 2)
|
|
goto out_locked;
|
|
}
|
|
out:
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
out_locked:
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
static bool is_system_glock(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
|
|
|
|
if (gl == m_ip->i_gl)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* do_xmote - Calls the DLM to change the state of a lock
|
|
* @gl: The lock state
|
|
* @gh: The holder (only for promotes)
|
|
* @target: The target lock state
|
|
*
|
|
*/
|
|
|
|
static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target)
|
|
__releases(&gl->gl_lockref.lock)
|
|
__acquires(&gl->gl_lockref.lock)
|
|
{
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
unsigned int lck_flags = (unsigned int)(gh ? gh->gh_flags : 0);
|
|
int ret;
|
|
|
|
if (target != LM_ST_UNLOCKED && glock_blocked_by_withdraw(gl) &&
|
|
gh && !(gh->gh_flags & LM_FLAG_NOEXP))
|
|
return;
|
|
lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP |
|
|
LM_FLAG_PRIORITY);
|
|
GLOCK_BUG_ON(gl, gl->gl_state == target);
|
|
GLOCK_BUG_ON(gl, gl->gl_state == gl->gl_target);
|
|
if ((target == LM_ST_UNLOCKED || target == LM_ST_DEFERRED) &&
|
|
glops->go_inval) {
|
|
/*
|
|
* If another process is already doing the invalidate, let that
|
|
* finish first. The glock state machine will get back to this
|
|
* holder again later.
|
|
*/
|
|
if (test_and_set_bit(GLF_INVALIDATE_IN_PROGRESS,
|
|
&gl->gl_flags))
|
|
return;
|
|
do_error(gl, 0); /* Fail queued try locks */
|
|
}
|
|
gl->gl_req = target;
|
|
set_bit(GLF_BLOCKING, &gl->gl_flags);
|
|
if ((gl->gl_req == LM_ST_UNLOCKED) ||
|
|
(gl->gl_state == LM_ST_EXCLUSIVE) ||
|
|
(lck_flags & (LM_FLAG_TRY|LM_FLAG_TRY_1CB)))
|
|
clear_bit(GLF_BLOCKING, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
if (glops->go_sync) {
|
|
ret = glops->go_sync(gl);
|
|
/* If we had a problem syncing (due to io errors or whatever,
|
|
* we should not invalidate the metadata or tell dlm to
|
|
* release the glock to other nodes.
|
|
*/
|
|
if (ret) {
|
|
if (cmpxchg(&sdp->sd_log_error, 0, ret)) {
|
|
fs_err(sdp, "Error %d syncing glock \n", ret);
|
|
gfs2_dump_glock(NULL, gl, true);
|
|
}
|
|
goto skip_inval;
|
|
}
|
|
}
|
|
if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags)) {
|
|
/*
|
|
* The call to go_sync should have cleared out the ail list.
|
|
* If there are still items, we have a problem. We ought to
|
|
* withdraw, but we can't because the withdraw code also uses
|
|
* glocks. Warn about the error, dump the glock, then fall
|
|
* through and wait for logd to do the withdraw for us.
|
|
*/
|
|
if ((atomic_read(&gl->gl_ail_count) != 0) &&
|
|
(!cmpxchg(&sdp->sd_log_error, 0, -EIO))) {
|
|
gfs2_glock_assert_warn(gl,
|
|
!atomic_read(&gl->gl_ail_count));
|
|
gfs2_dump_glock(NULL, gl, true);
|
|
}
|
|
glops->go_inval(gl, target == LM_ST_DEFERRED ? 0 : DIO_METADATA);
|
|
clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
|
|
}
|
|
|
|
skip_inval:
|
|
gfs2_glock_hold(gl);
|
|
/*
|
|
* Check for an error encountered since we called go_sync and go_inval.
|
|
* If so, we can't withdraw from the glock code because the withdraw
|
|
* code itself uses glocks (see function signal_our_withdraw) to
|
|
* change the mount to read-only. Most importantly, we must not call
|
|
* dlm to unlock the glock until the journal is in a known good state
|
|
* (after journal replay) otherwise other nodes may use the object
|
|
* (rgrp or dinode) and then later, journal replay will corrupt the
|
|
* file system. The best we can do here is wait for the logd daemon
|
|
* to see sd_log_error and withdraw, and in the meantime, requeue the
|
|
* work for later.
|
|
*
|
|
* We make a special exception for some system glocks, such as the
|
|
* system statfs inode glock, which needs to be granted before the
|
|
* gfs2_quotad daemon can exit, and that exit needs to finish before
|
|
* we can unmount the withdrawn file system.
|
|
*
|
|
* However, if we're just unlocking the lock (say, for unmount, when
|
|
* gfs2_gl_hash_clear calls clear_glock) and recovery is complete
|
|
* then it's okay to tell dlm to unlock it.
|
|
*/
|
|
if (unlikely(sdp->sd_log_error && !gfs2_withdrawn(sdp)))
|
|
gfs2_withdraw_delayed(sdp);
|
|
if (glock_blocked_by_withdraw(gl) &&
|
|
(target != LM_ST_UNLOCKED ||
|
|
test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags))) {
|
|
if (!is_system_glock(gl)) {
|
|
gfs2_glock_queue_work(gl, GL_GLOCK_DFT_HOLD);
|
|
goto out;
|
|
} else {
|
|
clear_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags);
|
|
}
|
|
}
|
|
|
|
if (sdp->sd_lockstruct.ls_ops->lm_lock) {
|
|
/* lock_dlm */
|
|
ret = sdp->sd_lockstruct.ls_ops->lm_lock(gl, target, lck_flags);
|
|
if (ret == -EINVAL && gl->gl_target == LM_ST_UNLOCKED &&
|
|
target == LM_ST_UNLOCKED &&
|
|
test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags)) {
|
|
finish_xmote(gl, target);
|
|
gfs2_glock_queue_work(gl, 0);
|
|
} else if (ret) {
|
|
fs_err(sdp, "lm_lock ret %d\n", ret);
|
|
GLOCK_BUG_ON(gl, !gfs2_withdrawn(sdp));
|
|
}
|
|
} else { /* lock_nolock */
|
|
finish_xmote(gl, target);
|
|
gfs2_glock_queue_work(gl, 0);
|
|
}
|
|
out:
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
/**
|
|
* run_queue - do all outstanding tasks related to a glock
|
|
* @gl: The glock in question
|
|
* @nonblock: True if we must not block in run_queue
|
|
*
|
|
*/
|
|
|
|
static void run_queue(struct gfs2_glock *gl, const int nonblock)
|
|
__releases(&gl->gl_lockref.lock)
|
|
__acquires(&gl->gl_lockref.lock)
|
|
{
|
|
struct gfs2_holder *gh = NULL;
|
|
int ret;
|
|
|
|
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags))
|
|
return;
|
|
|
|
GLOCK_BUG_ON(gl, test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags));
|
|
|
|
if (test_bit(GLF_DEMOTE, &gl->gl_flags) &&
|
|
gl->gl_demote_state != gl->gl_state) {
|
|
if (find_first_holder(gl))
|
|
goto out_unlock;
|
|
if (nonblock)
|
|
goto out_sched;
|
|
set_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags);
|
|
GLOCK_BUG_ON(gl, gl->gl_demote_state == LM_ST_EXCLUSIVE);
|
|
gl->gl_target = gl->gl_demote_state;
|
|
} else {
|
|
if (test_bit(GLF_DEMOTE, &gl->gl_flags))
|
|
gfs2_demote_wake(gl);
|
|
ret = do_promote(gl);
|
|
if (ret == 0)
|
|
goto out_unlock;
|
|
if (ret == 2)
|
|
goto out;
|
|
gh = find_first_waiter(gl);
|
|
gl->gl_target = gh->gh_state;
|
|
if (!(gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)))
|
|
do_error(gl, 0); /* Fail queued try locks */
|
|
}
|
|
do_xmote(gl, gh, gl->gl_target);
|
|
out:
|
|
return;
|
|
|
|
out_sched:
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
smp_mb__after_atomic();
|
|
gl->gl_lockref.count++;
|
|
__gfs2_glock_queue_work(gl, 0);
|
|
return;
|
|
|
|
out_unlock:
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
smp_mb__after_atomic();
|
|
return;
|
|
}
|
|
|
|
void gfs2_inode_remember_delete(struct gfs2_glock *gl, u64 generation)
|
|
{
|
|
struct gfs2_inode_lvb *ri = (void *)gl->gl_lksb.sb_lvbptr;
|
|
|
|
if (ri->ri_magic == 0)
|
|
ri->ri_magic = cpu_to_be32(GFS2_MAGIC);
|
|
if (ri->ri_magic == cpu_to_be32(GFS2_MAGIC))
|
|
ri->ri_generation_deleted = cpu_to_be64(generation);
|
|
}
|
|
|
|
bool gfs2_inode_already_deleted(struct gfs2_glock *gl, u64 generation)
|
|
{
|
|
struct gfs2_inode_lvb *ri = (void *)gl->gl_lksb.sb_lvbptr;
|
|
|
|
if (ri->ri_magic != cpu_to_be32(GFS2_MAGIC))
|
|
return false;
|
|
return generation <= be64_to_cpu(ri->ri_generation_deleted);
|
|
}
|
|
|
|
static void gfs2_glock_poke(struct gfs2_glock *gl)
|
|
{
|
|
int flags = LM_FLAG_TRY_1CB | LM_FLAG_ANY | GL_SKIP;
|
|
struct gfs2_holder gh;
|
|
int error;
|
|
|
|
__gfs2_holder_init(gl, LM_ST_SHARED, flags, &gh, _RET_IP_);
|
|
error = gfs2_glock_nq(&gh);
|
|
if (!error)
|
|
gfs2_glock_dq(&gh);
|
|
gfs2_holder_uninit(&gh);
|
|
}
|
|
|
|
static bool gfs2_try_evict(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_inode *ip;
|
|
bool evicted = false;
|
|
|
|
/*
|
|
* If there is contention on the iopen glock and we have an inode, try
|
|
* to grab and release the inode so that it can be evicted. This will
|
|
* allow the remote node to go ahead and delete the inode without us
|
|
* having to do it, which will avoid rgrp glock thrashing.
|
|
*
|
|
* The remote node is likely still holding the corresponding inode
|
|
* glock, so it will run before we get to verify that the delete has
|
|
* happened below.
|
|
*/
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
ip = gl->gl_object;
|
|
if (ip && !igrab(&ip->i_inode))
|
|
ip = NULL;
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
if (ip) {
|
|
struct gfs2_glock *inode_gl = NULL;
|
|
|
|
gl->gl_no_formal_ino = ip->i_no_formal_ino;
|
|
set_bit(GIF_DEFERRED_DELETE, &ip->i_flags);
|
|
d_prune_aliases(&ip->i_inode);
|
|
iput(&ip->i_inode);
|
|
|
|
/* If the inode was evicted, gl->gl_object will now be NULL. */
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
ip = gl->gl_object;
|
|
if (ip) {
|
|
inode_gl = ip->i_gl;
|
|
lockref_get(&inode_gl->gl_lockref);
|
|
clear_bit(GIF_DEFERRED_DELETE, &ip->i_flags);
|
|
}
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
if (inode_gl) {
|
|
gfs2_glock_poke(inode_gl);
|
|
gfs2_glock_put(inode_gl);
|
|
}
|
|
evicted = !ip;
|
|
}
|
|
return evicted;
|
|
}
|
|
|
|
static void delete_work_func(struct work_struct *work)
|
|
{
|
|
struct delayed_work *dwork = to_delayed_work(work);
|
|
struct gfs2_glock *gl = container_of(dwork, struct gfs2_glock, gl_delete);
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
struct inode *inode;
|
|
u64 no_addr = gl->gl_name.ln_number;
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
clear_bit(GLF_PENDING_DELETE, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
|
|
if (test_bit(GLF_DEMOTE, &gl->gl_flags)) {
|
|
/*
|
|
* If we can evict the inode, give the remote node trying to
|
|
* delete the inode some time before verifying that the delete
|
|
* has happened. Otherwise, if we cause contention on the inode glock
|
|
* immediately, the remote node will think that we still have
|
|
* the inode in use, and so it will give up waiting.
|
|
*
|
|
* If we can't evict the inode, signal to the remote node that
|
|
* the inode is still in use. We'll later try to delete the
|
|
* inode locally in gfs2_evict_inode.
|
|
*
|
|
* FIXME: We only need to verify that the remote node has
|
|
* deleted the inode because nodes before this remote delete
|
|
* rework won't cooperate. At a later time, when we no longer
|
|
* care about compatibility with such nodes, we can skip this
|
|
* step entirely.
|
|
*/
|
|
if (gfs2_try_evict(gl)) {
|
|
if (gfs2_queue_delete_work(gl, 5 * HZ))
|
|
return;
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
inode = gfs2_lookup_by_inum(sdp, no_addr, gl->gl_no_formal_ino,
|
|
GFS2_BLKST_UNLINKED);
|
|
if (!IS_ERR_OR_NULL(inode)) {
|
|
d_prune_aliases(inode);
|
|
iput(inode);
|
|
}
|
|
out:
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
static void glock_work_func(struct work_struct *work)
|
|
{
|
|
unsigned long delay = 0;
|
|
struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_work.work);
|
|
unsigned int drop_refs = 1;
|
|
|
|
if (test_and_clear_bit(GLF_REPLY_PENDING, &gl->gl_flags)) {
|
|
finish_xmote(gl, gl->gl_reply);
|
|
drop_refs++;
|
|
}
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
|
|
gl->gl_state != LM_ST_UNLOCKED &&
|
|
gl->gl_demote_state != LM_ST_EXCLUSIVE) {
|
|
unsigned long holdtime, now = jiffies;
|
|
|
|
holdtime = gl->gl_tchange + gl->gl_hold_time;
|
|
if (time_before(now, holdtime))
|
|
delay = holdtime - now;
|
|
|
|
if (!delay) {
|
|
clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
|
|
gfs2_set_demote(gl);
|
|
}
|
|
}
|
|
run_queue(gl, 0);
|
|
if (delay) {
|
|
/* Keep one glock reference for the work we requeue. */
|
|
drop_refs--;
|
|
if (gl->gl_name.ln_type != LM_TYPE_INODE)
|
|
delay = 0;
|
|
__gfs2_glock_queue_work(gl, delay);
|
|
}
|
|
|
|
/*
|
|
* Drop the remaining glock references manually here. (Mind that
|
|
* __gfs2_glock_queue_work depends on the lockref spinlock begin held
|
|
* here as well.)
|
|
*/
|
|
gl->gl_lockref.count -= drop_refs;
|
|
if (!gl->gl_lockref.count) {
|
|
__gfs2_glock_put(gl);
|
|
return;
|
|
}
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
static struct gfs2_glock *find_insert_glock(struct lm_lockname *name,
|
|
struct gfs2_glock *new)
|
|
{
|
|
struct wait_glock_queue wait;
|
|
wait_queue_head_t *wq = glock_waitqueue(name);
|
|
struct gfs2_glock *gl;
|
|
|
|
wait.name = name;
|
|
init_wait(&wait.wait);
|
|
wait.wait.func = glock_wake_function;
|
|
|
|
again:
|
|
prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
|
|
rcu_read_lock();
|
|
if (new) {
|
|
gl = rhashtable_lookup_get_insert_fast(&gl_hash_table,
|
|
&new->gl_node, ht_parms);
|
|
if (IS_ERR(gl))
|
|
goto out;
|
|
} else {
|
|
gl = rhashtable_lookup_fast(&gl_hash_table,
|
|
name, ht_parms);
|
|
}
|
|
if (gl && !lockref_get_not_dead(&gl->gl_lockref)) {
|
|
rcu_read_unlock();
|
|
schedule();
|
|
goto again;
|
|
}
|
|
out:
|
|
rcu_read_unlock();
|
|
finish_wait(wq, &wait.wait);
|
|
return gl;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_get() - Get a glock, or create one if one doesn't exist
|
|
* @sdp: The GFS2 superblock
|
|
* @number: the lock number
|
|
* @glops: The glock_operations to use
|
|
* @create: If 0, don't create the glock if it doesn't exist
|
|
* @glp: the glock is returned here
|
|
*
|
|
* This does not lock a glock, just finds/creates structures for one.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
|
|
const struct gfs2_glock_operations *glops, int create,
|
|
struct gfs2_glock **glp)
|
|
{
|
|
struct super_block *s = sdp->sd_vfs;
|
|
struct lm_lockname name = { .ln_number = number,
|
|
.ln_type = glops->go_type,
|
|
.ln_sbd = sdp };
|
|
struct gfs2_glock *gl, *tmp;
|
|
struct address_space *mapping;
|
|
struct kmem_cache *cachep;
|
|
int ret = 0;
|
|
|
|
gl = find_insert_glock(&name, NULL);
|
|
if (gl) {
|
|
*glp = gl;
|
|
return 0;
|
|
}
|
|
if (!create)
|
|
return -ENOENT;
|
|
|
|
if (glops->go_flags & GLOF_ASPACE)
|
|
cachep = gfs2_glock_aspace_cachep;
|
|
else
|
|
cachep = gfs2_glock_cachep;
|
|
gl = kmem_cache_alloc(cachep, GFP_NOFS);
|
|
if (!gl)
|
|
return -ENOMEM;
|
|
|
|
memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb));
|
|
|
|
if (glops->go_flags & GLOF_LVB) {
|
|
gl->gl_lksb.sb_lvbptr = kzalloc(GDLM_LVB_SIZE, GFP_NOFS);
|
|
if (!gl->gl_lksb.sb_lvbptr) {
|
|
kmem_cache_free(cachep, gl);
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
|
|
atomic_inc(&sdp->sd_glock_disposal);
|
|
gl->gl_node.next = NULL;
|
|
gl->gl_flags = glops->go_instantiate ? BIT(GLF_INSTANTIATE_NEEDED) : 0;
|
|
gl->gl_name = name;
|
|
lockdep_set_subclass(&gl->gl_lockref.lock, glops->go_subclass);
|
|
gl->gl_lockref.count = 1;
|
|
gl->gl_state = LM_ST_UNLOCKED;
|
|
gl->gl_target = LM_ST_UNLOCKED;
|
|
gl->gl_demote_state = LM_ST_EXCLUSIVE;
|
|
gl->gl_ops = glops;
|
|
gl->gl_dstamp = 0;
|
|
preempt_disable();
|
|
/* We use the global stats to estimate the initial per-glock stats */
|
|
gl->gl_stats = this_cpu_ptr(sdp->sd_lkstats)->lkstats[glops->go_type];
|
|
preempt_enable();
|
|
gl->gl_stats.stats[GFS2_LKS_DCOUNT] = 0;
|
|
gl->gl_stats.stats[GFS2_LKS_QCOUNT] = 0;
|
|
gl->gl_tchange = jiffies;
|
|
gl->gl_object = NULL;
|
|
gl->gl_hold_time = GL_GLOCK_DFT_HOLD;
|
|
INIT_DELAYED_WORK(&gl->gl_work, glock_work_func);
|
|
if (gl->gl_name.ln_type == LM_TYPE_IOPEN)
|
|
INIT_DELAYED_WORK(&gl->gl_delete, delete_work_func);
|
|
|
|
mapping = gfs2_glock2aspace(gl);
|
|
if (mapping) {
|
|
mapping->a_ops = &gfs2_meta_aops;
|
|
mapping->host = s->s_bdev->bd_inode;
|
|
mapping->flags = 0;
|
|
mapping_set_gfp_mask(mapping, GFP_NOFS);
|
|
mapping->private_data = NULL;
|
|
mapping->writeback_index = 0;
|
|
}
|
|
|
|
tmp = find_insert_glock(&name, gl);
|
|
if (!tmp) {
|
|
*glp = gl;
|
|
goto out;
|
|
}
|
|
if (IS_ERR(tmp)) {
|
|
ret = PTR_ERR(tmp);
|
|
goto out_free;
|
|
}
|
|
*glp = tmp;
|
|
|
|
out_free:
|
|
kfree(gl->gl_lksb.sb_lvbptr);
|
|
kmem_cache_free(cachep, gl);
|
|
if (atomic_dec_and_test(&sdp->sd_glock_disposal))
|
|
wake_up(&sdp->sd_glock_wait);
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* __gfs2_holder_init - initialize a struct gfs2_holder in the default way
|
|
* @gl: the glock
|
|
* @state: the state we're requesting
|
|
* @flags: the modifier flags
|
|
* @gh: the holder structure
|
|
*
|
|
*/
|
|
|
|
void __gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, u16 flags,
|
|
struct gfs2_holder *gh, unsigned long ip)
|
|
{
|
|
INIT_LIST_HEAD(&gh->gh_list);
|
|
gh->gh_gl = gl;
|
|
gh->gh_ip = ip;
|
|
gh->gh_owner_pid = get_pid(task_pid(current));
|
|
gh->gh_state = state;
|
|
gh->gh_flags = flags;
|
|
gh->gh_error = 0;
|
|
gh->gh_iflags = 0;
|
|
gfs2_glock_hold(gl);
|
|
}
|
|
|
|
/**
|
|
* gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it
|
|
* @state: the state we're requesting
|
|
* @flags: the modifier flags
|
|
* @gh: the holder structure
|
|
*
|
|
* Don't mess with the glock.
|
|
*
|
|
*/
|
|
|
|
void gfs2_holder_reinit(unsigned int state, u16 flags, struct gfs2_holder *gh)
|
|
{
|
|
gh->gh_state = state;
|
|
gh->gh_flags = flags;
|
|
gh->gh_iflags = 0;
|
|
gh->gh_ip = _RET_IP_;
|
|
put_pid(gh->gh_owner_pid);
|
|
gh->gh_owner_pid = get_pid(task_pid(current));
|
|
}
|
|
|
|
/**
|
|
* gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
|
|
* @gh: the holder structure
|
|
*
|
|
*/
|
|
|
|
void gfs2_holder_uninit(struct gfs2_holder *gh)
|
|
{
|
|
put_pid(gh->gh_owner_pid);
|
|
gfs2_glock_put(gh->gh_gl);
|
|
gfs2_holder_mark_uninitialized(gh);
|
|
gh->gh_ip = 0;
|
|
}
|
|
|
|
static void gfs2_glock_update_hold_time(struct gfs2_glock *gl,
|
|
unsigned long start_time)
|
|
{
|
|
/* Have we waited longer that a second? */
|
|
if (time_after(jiffies, start_time + HZ)) {
|
|
/* Lengthen the minimum hold time. */
|
|
gl->gl_hold_time = min(gl->gl_hold_time + GL_GLOCK_HOLD_INCR,
|
|
GL_GLOCK_MAX_HOLD);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_wait - wait on a glock acquisition
|
|
* @gh: the glock holder
|
|
*
|
|
* Returns: 0 on success
|
|
*/
|
|
|
|
int gfs2_glock_wait(struct gfs2_holder *gh)
|
|
{
|
|
unsigned long start_time = jiffies;
|
|
|
|
might_sleep();
|
|
wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE);
|
|
gfs2_glock_update_hold_time(gh->gh_gl, start_time);
|
|
return gh->gh_error;
|
|
}
|
|
|
|
static int glocks_pending(unsigned int num_gh, struct gfs2_holder *ghs)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < num_gh; i++)
|
|
if (test_bit(HIF_WAIT, &ghs[i].gh_iflags))
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_async_wait - wait on multiple asynchronous glock acquisitions
|
|
* @num_gh: the number of holders in the array
|
|
* @ghs: the glock holder array
|
|
*
|
|
* Returns: 0 on success, meaning all glocks have been granted and are held.
|
|
* -ESTALE if the request timed out, meaning all glocks were released,
|
|
* and the caller should retry the operation.
|
|
*/
|
|
|
|
int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs)
|
|
{
|
|
struct gfs2_sbd *sdp = ghs[0].gh_gl->gl_name.ln_sbd;
|
|
int i, ret = 0, timeout = 0;
|
|
unsigned long start_time = jiffies;
|
|
bool keep_waiting;
|
|
|
|
might_sleep();
|
|
/*
|
|
* Total up the (minimum hold time * 2) of all glocks and use that to
|
|
* determine the max amount of time we should wait.
|
|
*/
|
|
for (i = 0; i < num_gh; i++)
|
|
timeout += ghs[i].gh_gl->gl_hold_time << 1;
|
|
|
|
wait_for_dlm:
|
|
if (!wait_event_timeout(sdp->sd_async_glock_wait,
|
|
!glocks_pending(num_gh, ghs), timeout))
|
|
ret = -ESTALE; /* request timed out. */
|
|
|
|
/*
|
|
* If dlm granted all our requests, we need to adjust the glock
|
|
* minimum hold time values according to how long we waited.
|
|
*
|
|
* If our request timed out, we need to repeatedly release any held
|
|
* glocks we acquired thus far to allow dlm to acquire the remaining
|
|
* glocks without deadlocking. We cannot currently cancel outstanding
|
|
* glock acquisitions.
|
|
*
|
|
* The HIF_WAIT bit tells us which requests still need a response from
|
|
* dlm.
|
|
*
|
|
* If dlm sent us any errors, we return the first error we find.
|
|
*/
|
|
keep_waiting = false;
|
|
for (i = 0; i < num_gh; i++) {
|
|
/* Skip holders we have already dequeued below. */
|
|
if (!gfs2_holder_queued(&ghs[i]))
|
|
continue;
|
|
/* Skip holders with a pending DLM response. */
|
|
if (test_bit(HIF_WAIT, &ghs[i].gh_iflags)) {
|
|
keep_waiting = true;
|
|
continue;
|
|
}
|
|
|
|
if (test_bit(HIF_HOLDER, &ghs[i].gh_iflags)) {
|
|
if (ret == -ESTALE)
|
|
gfs2_glock_dq(&ghs[i]);
|
|
else
|
|
gfs2_glock_update_hold_time(ghs[i].gh_gl,
|
|
start_time);
|
|
}
|
|
if (!ret)
|
|
ret = ghs[i].gh_error;
|
|
}
|
|
|
|
if (keep_waiting)
|
|
goto wait_for_dlm;
|
|
|
|
/*
|
|
* At this point, we've either acquired all locks or released them all.
|
|
*/
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* handle_callback - process a demote request
|
|
* @gl: the glock
|
|
* @state: the state the caller wants us to change to
|
|
* @delay: zero to demote immediately; otherwise pending demote
|
|
* @remote: true if this came from a different cluster node
|
|
*
|
|
* There are only two requests that we are going to see in actual
|
|
* practise: LM_ST_SHARED and LM_ST_UNLOCKED
|
|
*/
|
|
|
|
static void handle_callback(struct gfs2_glock *gl, unsigned int state,
|
|
unsigned long delay, bool remote)
|
|
{
|
|
if (delay)
|
|
set_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
|
|
else
|
|
gfs2_set_demote(gl);
|
|
if (gl->gl_demote_state == LM_ST_EXCLUSIVE) {
|
|
gl->gl_demote_state = state;
|
|
gl->gl_demote_time = jiffies;
|
|
} else if (gl->gl_demote_state != LM_ST_UNLOCKED &&
|
|
gl->gl_demote_state != state) {
|
|
gl->gl_demote_state = LM_ST_UNLOCKED;
|
|
}
|
|
if (gl->gl_ops->go_callback)
|
|
gl->gl_ops->go_callback(gl, remote);
|
|
trace_gfs2_demote_rq(gl, remote);
|
|
}
|
|
|
|
void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...)
|
|
{
|
|
struct va_format vaf;
|
|
va_list args;
|
|
|
|
va_start(args, fmt);
|
|
|
|
if (seq) {
|
|
seq_vprintf(seq, fmt, args);
|
|
} else {
|
|
vaf.fmt = fmt;
|
|
vaf.va = &args;
|
|
|
|
pr_err("%pV", &vaf);
|
|
}
|
|
|
|
va_end(args);
|
|
}
|
|
|
|
/**
|
|
* add_to_queue - Add a holder to the wait queue (but look for recursion)
|
|
* @gh: the holder structure to add
|
|
*
|
|
* Eventually we should move the recursive locking trap to a
|
|
* debugging option or something like that. This is the fast
|
|
* path and needs to have the minimum number of distractions.
|
|
*
|
|
*/
|
|
|
|
static inline void add_to_queue(struct gfs2_holder *gh)
|
|
__releases(&gl->gl_lockref.lock)
|
|
__acquires(&gl->gl_lockref.lock)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
struct list_head *insert_pt = NULL;
|
|
struct gfs2_holder *gh2;
|
|
int try_futile = 0;
|
|
|
|
GLOCK_BUG_ON(gl, gh->gh_owner_pid == NULL);
|
|
if (test_and_set_bit(HIF_WAIT, &gh->gh_iflags))
|
|
GLOCK_BUG_ON(gl, true);
|
|
|
|
if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
|
|
if (test_bit(GLF_LOCK, &gl->gl_flags)) {
|
|
struct gfs2_holder *first_gh;
|
|
|
|
first_gh = find_first_strong_holder(gl);
|
|
try_futile = !may_grant(gl, first_gh, gh);
|
|
}
|
|
if (test_bit(GLF_INVALIDATE_IN_PROGRESS, &gl->gl_flags))
|
|
goto fail;
|
|
}
|
|
|
|
list_for_each_entry(gh2, &gl->gl_holders, gh_list) {
|
|
if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid &&
|
|
(gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK) &&
|
|
!test_bit(HIF_MAY_DEMOTE, &gh2->gh_iflags)))
|
|
goto trap_recursive;
|
|
if (try_futile &&
|
|
!(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) {
|
|
fail:
|
|
gh->gh_error = GLR_TRYFAILED;
|
|
gfs2_holder_wake(gh);
|
|
return;
|
|
}
|
|
if (test_bit(HIF_HOLDER, &gh2->gh_iflags))
|
|
continue;
|
|
if (unlikely((gh->gh_flags & LM_FLAG_PRIORITY) && !insert_pt))
|
|
insert_pt = &gh2->gh_list;
|
|
}
|
|
trace_gfs2_glock_queue(gh, 1);
|
|
gfs2_glstats_inc(gl, GFS2_LKS_QCOUNT);
|
|
gfs2_sbstats_inc(gl, GFS2_LKS_QCOUNT);
|
|
if (likely(insert_pt == NULL)) {
|
|
list_add_tail(&gh->gh_list, &gl->gl_holders);
|
|
if (unlikely(gh->gh_flags & LM_FLAG_PRIORITY))
|
|
goto do_cancel;
|
|
return;
|
|
}
|
|
list_add_tail(&gh->gh_list, insert_pt);
|
|
do_cancel:
|
|
gh = list_first_entry(&gl->gl_holders, struct gfs2_holder, gh_list);
|
|
if (!(gh->gh_flags & LM_FLAG_PRIORITY)) {
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
if (sdp->sd_lockstruct.ls_ops->lm_cancel)
|
|
sdp->sd_lockstruct.ls_ops->lm_cancel(gl);
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
}
|
|
return;
|
|
|
|
trap_recursive:
|
|
fs_err(sdp, "original: %pSR\n", (void *)gh2->gh_ip);
|
|
fs_err(sdp, "pid: %d\n", pid_nr(gh2->gh_owner_pid));
|
|
fs_err(sdp, "lock type: %d req lock state : %d\n",
|
|
gh2->gh_gl->gl_name.ln_type, gh2->gh_state);
|
|
fs_err(sdp, "new: %pSR\n", (void *)gh->gh_ip);
|
|
fs_err(sdp, "pid: %d\n", pid_nr(gh->gh_owner_pid));
|
|
fs_err(sdp, "lock type: %d req lock state : %d\n",
|
|
gh->gh_gl->gl_name.ln_type, gh->gh_state);
|
|
gfs2_dump_glock(NULL, gl, true);
|
|
BUG();
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_nq - enqueue a struct gfs2_holder onto a glock (acquire a glock)
|
|
* @gh: the holder structure
|
|
*
|
|
* if (gh->gh_flags & GL_ASYNC), this never returns an error
|
|
*
|
|
* Returns: 0, GLR_TRYFAILED, or errno on failure
|
|
*/
|
|
|
|
int gfs2_glock_nq(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
int error = 0;
|
|
|
|
if (glock_blocked_by_withdraw(gl) && !(gh->gh_flags & LM_FLAG_NOEXP))
|
|
return -EIO;
|
|
|
|
if (test_bit(GLF_LRU, &gl->gl_flags))
|
|
gfs2_glock_remove_from_lru(gl);
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
add_to_queue(gh);
|
|
if (unlikely((LM_FLAG_NOEXP & gh->gh_flags) &&
|
|
test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))) {
|
|
set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
|
|
gl->gl_lockref.count++;
|
|
__gfs2_glock_queue_work(gl, 0);
|
|
}
|
|
run_queue(gl, 1);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
|
|
if (!(gh->gh_flags & GL_ASYNC))
|
|
error = gfs2_glock_wait(gh);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_poll - poll to see if an async request has been completed
|
|
* @gh: the holder
|
|
*
|
|
* Returns: 1 if the request is ready to be gfs2_glock_wait()ed on
|
|
*/
|
|
|
|
int gfs2_glock_poll(struct gfs2_holder *gh)
|
|
{
|
|
return test_bit(HIF_WAIT, &gh->gh_iflags) ? 0 : 1;
|
|
}
|
|
|
|
static inline bool needs_demote(struct gfs2_glock *gl)
|
|
{
|
|
return (test_bit(GLF_DEMOTE, &gl->gl_flags) ||
|
|
test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags));
|
|
}
|
|
|
|
static void __gfs2_glock_dq(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
unsigned delay = 0;
|
|
int fast_path = 0;
|
|
|
|
/*
|
|
* This while loop is similar to function demote_incompat_holders:
|
|
* If the glock is due to be demoted (which may be from another node
|
|
* or even if this holder is GL_NOCACHE), the weak holders are
|
|
* demoted as well, allowing the glock to be demoted.
|
|
*/
|
|
while (gh) {
|
|
/*
|
|
* If we're in the process of file system withdraw, we cannot
|
|
* just dequeue any glocks until our journal is recovered, lest
|
|
* we introduce file system corruption. We need two exceptions
|
|
* to this rule: We need to allow unlocking of nondisk glocks
|
|
* and the glock for our own journal that needs recovery.
|
|
*/
|
|
if (test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags) &&
|
|
glock_blocked_by_withdraw(gl) &&
|
|
gh->gh_gl != sdp->sd_jinode_gl) {
|
|
sdp->sd_glock_dqs_held++;
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
might_sleep();
|
|
wait_on_bit(&sdp->sd_flags, SDF_WITHDRAW_RECOVERY,
|
|
TASK_UNINTERRUPTIBLE);
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
/*
|
|
* This holder should not be cached, so mark it for demote.
|
|
* Note: this should be done before the check for needs_demote
|
|
* below.
|
|
*/
|
|
if (gh->gh_flags & GL_NOCACHE)
|
|
handle_callback(gl, LM_ST_UNLOCKED, 0, false);
|
|
|
|
list_del_init(&gh->gh_list);
|
|
clear_bit(HIF_HOLDER, &gh->gh_iflags);
|
|
trace_gfs2_glock_queue(gh, 0);
|
|
|
|
/*
|
|
* If there hasn't been a demote request we are done.
|
|
* (Let the remaining holders, if any, keep holding it.)
|
|
*/
|
|
if (!needs_demote(gl)) {
|
|
if (list_empty(&gl->gl_holders))
|
|
fast_path = 1;
|
|
break;
|
|
}
|
|
/*
|
|
* If we have another strong holder (we cannot auto-demote)
|
|
* we are done. It keeps holding it until it is done.
|
|
*/
|
|
if (find_first_strong_holder(gl))
|
|
break;
|
|
|
|
/*
|
|
* If we have a weak holder at the head of the list, it
|
|
* (and all others like it) must be auto-demoted. If there
|
|
* are no more weak holders, we exit the while loop.
|
|
*/
|
|
gh = find_first_holder(gl);
|
|
}
|
|
|
|
if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl))
|
|
gfs2_glock_add_to_lru(gl);
|
|
|
|
if (unlikely(!fast_path)) {
|
|
gl->gl_lockref.count++;
|
|
if (test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) &&
|
|
!test_bit(GLF_DEMOTE, &gl->gl_flags) &&
|
|
gl->gl_name.ln_type == LM_TYPE_INODE)
|
|
delay = gl->gl_hold_time;
|
|
__gfs2_glock_queue_work(gl, delay);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_dq - dequeue a struct gfs2_holder from a glock (release a glock)
|
|
* @gh: the glock holder
|
|
*
|
|
*/
|
|
void gfs2_glock_dq(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
__gfs2_glock_dq(gh);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
void gfs2_glock_dq_wait(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
gfs2_glock_dq(gh);
|
|
might_sleep();
|
|
wait_on_bit(&gl->gl_flags, GLF_DEMOTE, TASK_UNINTERRUPTIBLE);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_dq_uninit - dequeue a holder from a glock and initialize it
|
|
* @gh: the holder structure
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_dq_uninit(struct gfs2_holder *gh)
|
|
{
|
|
gfs2_glock_dq(gh);
|
|
gfs2_holder_uninit(gh);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_nq_num - acquire a glock based on lock number
|
|
* @sdp: the filesystem
|
|
* @number: the lock number
|
|
* @glops: the glock operations for the type of glock
|
|
* @state: the state to acquire the glock in
|
|
* @flags: modifier flags for the acquisition
|
|
* @gh: the struct gfs2_holder
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
|
|
const struct gfs2_glock_operations *glops,
|
|
unsigned int state, u16 flags, struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
int error;
|
|
|
|
error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
|
|
if (!error) {
|
|
error = gfs2_glock_nq_init(gl, state, flags, gh);
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* glock_compare - Compare two struct gfs2_glock structures for sorting
|
|
* @arg_a: the first structure
|
|
* @arg_b: the second structure
|
|
*
|
|
*/
|
|
|
|
static int glock_compare(const void *arg_a, const void *arg_b)
|
|
{
|
|
const struct gfs2_holder *gh_a = *(const struct gfs2_holder **)arg_a;
|
|
const struct gfs2_holder *gh_b = *(const struct gfs2_holder **)arg_b;
|
|
const struct lm_lockname *a = &gh_a->gh_gl->gl_name;
|
|
const struct lm_lockname *b = &gh_b->gh_gl->gl_name;
|
|
|
|
if (a->ln_number > b->ln_number)
|
|
return 1;
|
|
if (a->ln_number < b->ln_number)
|
|
return -1;
|
|
BUG_ON(gh_a->gh_gl->gl_ops->go_type == gh_b->gh_gl->gl_ops->go_type);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* nq_m_sync - synchonously acquire more than one glock in deadlock free order
|
|
* @num_gh: the number of structures
|
|
* @ghs: an array of struct gfs2_holder structures
|
|
* @p: placeholder for the holder structure to pass back
|
|
*
|
|
* Returns: 0 on success (all glocks acquired),
|
|
* errno on failure (no glocks acquired)
|
|
*/
|
|
|
|
static int nq_m_sync(unsigned int num_gh, struct gfs2_holder *ghs,
|
|
struct gfs2_holder **p)
|
|
{
|
|
unsigned int x;
|
|
int error = 0;
|
|
|
|
for (x = 0; x < num_gh; x++)
|
|
p[x] = &ghs[x];
|
|
|
|
sort(p, num_gh, sizeof(struct gfs2_holder *), glock_compare, NULL);
|
|
|
|
for (x = 0; x < num_gh; x++) {
|
|
p[x]->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
|
|
|
|
error = gfs2_glock_nq(p[x]);
|
|
if (error) {
|
|
while (x--)
|
|
gfs2_glock_dq(p[x]);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_nq_m - acquire multiple glocks
|
|
* @num_gh: the number of structures
|
|
* @ghs: an array of struct gfs2_holder structures
|
|
*
|
|
*
|
|
* Returns: 0 on success (all glocks acquired),
|
|
* errno on failure (no glocks acquired)
|
|
*/
|
|
|
|
int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs)
|
|
{
|
|
struct gfs2_holder *tmp[4];
|
|
struct gfs2_holder **pph = tmp;
|
|
int error = 0;
|
|
|
|
switch(num_gh) {
|
|
case 0:
|
|
return 0;
|
|
case 1:
|
|
ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
|
|
return gfs2_glock_nq(ghs);
|
|
default:
|
|
if (num_gh <= 4)
|
|
break;
|
|
pph = kmalloc_array(num_gh, sizeof(struct gfs2_holder *),
|
|
GFP_NOFS);
|
|
if (!pph)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
error = nq_m_sync(num_gh, ghs, pph);
|
|
|
|
if (pph != tmp)
|
|
kfree(pph);
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_dq_m - release multiple glocks
|
|
* @num_gh: the number of structures
|
|
* @ghs: an array of struct gfs2_holder structures
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs)
|
|
{
|
|
while (num_gh--)
|
|
gfs2_glock_dq(&ghs[num_gh]);
|
|
}
|
|
|
|
void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state)
|
|
{
|
|
unsigned long delay = 0;
|
|
unsigned long holdtime;
|
|
unsigned long now = jiffies;
|
|
|
|
gfs2_glock_hold(gl);
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
holdtime = gl->gl_tchange + gl->gl_hold_time;
|
|
if (!list_empty(&gl->gl_holders) &&
|
|
gl->gl_name.ln_type == LM_TYPE_INODE) {
|
|
if (time_before(now, holdtime))
|
|
delay = holdtime - now;
|
|
if (test_bit(GLF_REPLY_PENDING, &gl->gl_flags))
|
|
delay = gl->gl_hold_time;
|
|
}
|
|
/*
|
|
* Note 1: We cannot call demote_incompat_holders from handle_callback
|
|
* or gfs2_set_demote due to recursion problems like: gfs2_glock_dq ->
|
|
* handle_callback -> demote_incompat_holders -> gfs2_glock_dq
|
|
* Plus, we only want to demote the holders if the request comes from
|
|
* a remote cluster node because local holder conflicts are resolved
|
|
* elsewhere.
|
|
*
|
|
* Note 2: if a remote node wants this glock in EX mode, lock_dlm will
|
|
* request that we set our state to UNLOCKED. Here we mock up a holder
|
|
* to make it look like someone wants the lock EX locally. Any SH
|
|
* and DF requests should be able to share the lock without demoting.
|
|
*
|
|
* Note 3: We only want to demote the demoteable holders when there
|
|
* are no more strong holders. The demoteable holders might as well
|
|
* keep the glock until the last strong holder is done with it.
|
|
*/
|
|
if (!find_first_strong_holder(gl)) {
|
|
struct gfs2_holder mock_gh = {
|
|
.gh_gl = gl,
|
|
.gh_state = (state == LM_ST_UNLOCKED) ?
|
|
LM_ST_EXCLUSIVE : state,
|
|
.gh_iflags = BIT(HIF_HOLDER)
|
|
};
|
|
|
|
demote_incompat_holders(gl, &mock_gh);
|
|
}
|
|
handle_callback(gl, state, delay, true);
|
|
__gfs2_glock_queue_work(gl, delay);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
/**
|
|
* gfs2_should_freeze - Figure out if glock should be frozen
|
|
* @gl: The glock in question
|
|
*
|
|
* Glocks are not frozen if (a) the result of the dlm operation is
|
|
* an error, (b) the locking operation was an unlock operation or
|
|
* (c) if there is a "noexp" flagged request anywhere in the queue
|
|
*
|
|
* Returns: 1 if freezing should occur, 0 otherwise
|
|
*/
|
|
|
|
static int gfs2_should_freeze(const struct gfs2_glock *gl)
|
|
{
|
|
const struct gfs2_holder *gh;
|
|
|
|
if (gl->gl_reply & ~LM_OUT_ST_MASK)
|
|
return 0;
|
|
if (gl->gl_target == LM_ST_UNLOCKED)
|
|
return 0;
|
|
|
|
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
|
|
if (test_bit(HIF_HOLDER, &gh->gh_iflags))
|
|
continue;
|
|
if (LM_FLAG_NOEXP & gh->gh_flags)
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_complete - Callback used by locking
|
|
* @gl: Pointer to the glock
|
|
* @ret: The return value from the dlm
|
|
*
|
|
* The gl_reply field is under the gl_lockref.lock lock so that it is ok
|
|
* to use a bitfield shared with other glock state fields.
|
|
*/
|
|
|
|
void gfs2_glock_complete(struct gfs2_glock *gl, int ret)
|
|
{
|
|
struct lm_lockstruct *ls = &gl->gl_name.ln_sbd->sd_lockstruct;
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
gl->gl_reply = ret;
|
|
|
|
if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))) {
|
|
if (gfs2_should_freeze(gl)) {
|
|
set_bit(GLF_FROZEN, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
return;
|
|
}
|
|
}
|
|
|
|
gl->gl_lockref.count++;
|
|
set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
|
|
__gfs2_glock_queue_work(gl, 0);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
static int glock_cmp(void *priv, const struct list_head *a,
|
|
const struct list_head *b)
|
|
{
|
|
struct gfs2_glock *gla, *glb;
|
|
|
|
gla = list_entry(a, struct gfs2_glock, gl_lru);
|
|
glb = list_entry(b, struct gfs2_glock, gl_lru);
|
|
|
|
if (gla->gl_name.ln_number > glb->gl_name.ln_number)
|
|
return 1;
|
|
if (gla->gl_name.ln_number < glb->gl_name.ln_number)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_dispose_glock_lru - Demote a list of glocks
|
|
* @list: The list to dispose of
|
|
*
|
|
* Disposing of glocks may involve disk accesses, so that here we sort
|
|
* the glocks by number (i.e. disk location of the inodes) so that if
|
|
* there are any such accesses, they'll be sent in order (mostly).
|
|
*
|
|
* Must be called under the lru_lock, but may drop and retake this
|
|
* lock. While the lru_lock is dropped, entries may vanish from the
|
|
* list, but no new entries will appear on the list (since it is
|
|
* private)
|
|
*/
|
|
|
|
static void gfs2_dispose_glock_lru(struct list_head *list)
|
|
__releases(&lru_lock)
|
|
__acquires(&lru_lock)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
|
|
list_sort(NULL, list, glock_cmp);
|
|
|
|
while(!list_empty(list)) {
|
|
gl = list_first_entry(list, struct gfs2_glock, gl_lru);
|
|
list_del_init(&gl->gl_lru);
|
|
clear_bit(GLF_LRU, &gl->gl_flags);
|
|
if (!spin_trylock(&gl->gl_lockref.lock)) {
|
|
add_back_to_lru:
|
|
list_add(&gl->gl_lru, &lru_list);
|
|
set_bit(GLF_LRU, &gl->gl_flags);
|
|
atomic_inc(&lru_count);
|
|
continue;
|
|
}
|
|
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
goto add_back_to_lru;
|
|
}
|
|
gl->gl_lockref.count++;
|
|
if (demote_ok(gl))
|
|
handle_callback(gl, LM_ST_UNLOCKED, 0, false);
|
|
WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
|
|
__gfs2_glock_queue_work(gl, 0);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
cond_resched_lock(&lru_lock);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_scan_glock_lru - Scan the LRU looking for locks to demote
|
|
* @nr: The number of entries to scan
|
|
*
|
|
* This function selects the entries on the LRU which are able to
|
|
* be demoted, and then kicks off the process by calling
|
|
* gfs2_dispose_glock_lru() above.
|
|
*/
|
|
|
|
static long gfs2_scan_glock_lru(int nr)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
LIST_HEAD(skipped);
|
|
LIST_HEAD(dispose);
|
|
long freed = 0;
|
|
|
|
spin_lock(&lru_lock);
|
|
while ((nr-- >= 0) && !list_empty(&lru_list)) {
|
|
gl = list_first_entry(&lru_list, struct gfs2_glock, gl_lru);
|
|
|
|
/* Test for being demotable */
|
|
if (!test_bit(GLF_LOCK, &gl->gl_flags)) {
|
|
list_move(&gl->gl_lru, &dispose);
|
|
atomic_dec(&lru_count);
|
|
freed++;
|
|
continue;
|
|
}
|
|
|
|
list_move(&gl->gl_lru, &skipped);
|
|
}
|
|
list_splice(&skipped, &lru_list);
|
|
if (!list_empty(&dispose))
|
|
gfs2_dispose_glock_lru(&dispose);
|
|
spin_unlock(&lru_lock);
|
|
|
|
return freed;
|
|
}
|
|
|
|
static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
if (!(sc->gfp_mask & __GFP_FS))
|
|
return SHRINK_STOP;
|
|
return gfs2_scan_glock_lru(sc->nr_to_scan);
|
|
}
|
|
|
|
static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
|
|
struct shrink_control *sc)
|
|
{
|
|
return vfs_pressure_ratio(atomic_read(&lru_count));
|
|
}
|
|
|
|
static struct shrinker glock_shrinker = {
|
|
.seeks = DEFAULT_SEEKS,
|
|
.count_objects = gfs2_glock_shrink_count,
|
|
.scan_objects = gfs2_glock_shrink_scan,
|
|
};
|
|
|
|
/**
|
|
* glock_hash_walk - Call a function for glock in a hash bucket
|
|
* @examiner: the function
|
|
* @sdp: the filesystem
|
|
*
|
|
* Note that the function can be called multiple times on the same
|
|
* object. So the user must ensure that the function can cope with
|
|
* that.
|
|
*/
|
|
|
|
static void glock_hash_walk(glock_examiner examiner, const struct gfs2_sbd *sdp)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
struct rhashtable_iter iter;
|
|
|
|
rhashtable_walk_enter(&gl_hash_table, &iter);
|
|
|
|
do {
|
|
rhashtable_walk_start(&iter);
|
|
|
|
while ((gl = rhashtable_walk_next(&iter)) && !IS_ERR(gl)) {
|
|
if (gl->gl_name.ln_sbd == sdp)
|
|
examiner(gl);
|
|
}
|
|
|
|
rhashtable_walk_stop(&iter);
|
|
} while (cond_resched(), gl == ERR_PTR(-EAGAIN));
|
|
|
|
rhashtable_walk_exit(&iter);
|
|
}
|
|
|
|
bool gfs2_queue_delete_work(struct gfs2_glock *gl, unsigned long delay)
|
|
{
|
|
bool queued;
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
queued = queue_delayed_work(gfs2_delete_workqueue,
|
|
&gl->gl_delete, delay);
|
|
if (queued)
|
|
set_bit(GLF_PENDING_DELETE, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
return queued;
|
|
}
|
|
|
|
void gfs2_cancel_delete_work(struct gfs2_glock *gl)
|
|
{
|
|
if (cancel_delayed_work(&gl->gl_delete)) {
|
|
clear_bit(GLF_PENDING_DELETE, &gl->gl_flags);
|
|
gfs2_glock_put(gl);
|
|
}
|
|
}
|
|
|
|
bool gfs2_delete_work_queued(const struct gfs2_glock *gl)
|
|
{
|
|
return test_bit(GLF_PENDING_DELETE, &gl->gl_flags);
|
|
}
|
|
|
|
static void flush_delete_work(struct gfs2_glock *gl)
|
|
{
|
|
if (gl->gl_name.ln_type == LM_TYPE_IOPEN) {
|
|
if (cancel_delayed_work(&gl->gl_delete)) {
|
|
queue_delayed_work(gfs2_delete_workqueue,
|
|
&gl->gl_delete, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
void gfs2_flush_delete_work(struct gfs2_sbd *sdp)
|
|
{
|
|
glock_hash_walk(flush_delete_work, sdp);
|
|
flush_workqueue(gfs2_delete_workqueue);
|
|
}
|
|
|
|
/**
|
|
* thaw_glock - thaw out a glock which has an unprocessed reply waiting
|
|
* @gl: The glock to thaw
|
|
*
|
|
*/
|
|
|
|
static void thaw_glock(struct gfs2_glock *gl)
|
|
{
|
|
if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags))
|
|
return;
|
|
if (!lockref_get_not_dead(&gl->gl_lockref))
|
|
return;
|
|
set_bit(GLF_REPLY_PENDING, &gl->gl_flags);
|
|
gfs2_glock_queue_work(gl, 0);
|
|
}
|
|
|
|
/**
|
|
* clear_glock - look at a glock and see if we can free it from glock cache
|
|
* @gl: the glock to look at
|
|
*
|
|
*/
|
|
|
|
static void clear_glock(struct gfs2_glock *gl)
|
|
{
|
|
gfs2_glock_remove_from_lru(gl);
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
if (!__lockref_is_dead(&gl->gl_lockref)) {
|
|
gl->gl_lockref.count++;
|
|
if (gl->gl_state != LM_ST_UNLOCKED)
|
|
handle_callback(gl, LM_ST_UNLOCKED, 0, false);
|
|
__gfs2_glock_queue_work(gl, 0);
|
|
}
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_thaw - Thaw any frozen glocks
|
|
* @sdp: The super block
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_thaw(struct gfs2_sbd *sdp)
|
|
{
|
|
glock_hash_walk(thaw_glock, sdp);
|
|
}
|
|
|
|
static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
|
|
{
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
gfs2_dump_glock(seq, gl, fsid);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
static void dump_glock_func(struct gfs2_glock *gl)
|
|
{
|
|
dump_glock(NULL, gl, true);
|
|
}
|
|
|
|
/**
|
|
* gfs2_gl_hash_clear - Empty out the glock hash table
|
|
* @sdp: the filesystem
|
|
*
|
|
* Called when unmounting the filesystem.
|
|
*/
|
|
|
|
void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
|
|
{
|
|
set_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags);
|
|
flush_workqueue(glock_workqueue);
|
|
glock_hash_walk(clear_glock, sdp);
|
|
flush_workqueue(glock_workqueue);
|
|
wait_event_timeout(sdp->sd_glock_wait,
|
|
atomic_read(&sdp->sd_glock_disposal) == 0,
|
|
HZ * 600);
|
|
glock_hash_walk(dump_glock_func, sdp);
|
|
}
|
|
|
|
void gfs2_glock_finish_truncate(struct gfs2_inode *ip)
|
|
{
|
|
struct gfs2_glock *gl = ip->i_gl;
|
|
int ret;
|
|
|
|
ret = gfs2_truncatei_resume(ip);
|
|
gfs2_glock_assert_withdraw(gl, ret == 0);
|
|
|
|
spin_lock(&gl->gl_lockref.lock);
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
run_queue(gl, 1);
|
|
spin_unlock(&gl->gl_lockref.lock);
|
|
}
|
|
|
|
static const char *state2str(unsigned state)
|
|
{
|
|
switch(state) {
|
|
case LM_ST_UNLOCKED:
|
|
return "UN";
|
|
case LM_ST_SHARED:
|
|
return "SH";
|
|
case LM_ST_DEFERRED:
|
|
return "DF";
|
|
case LM_ST_EXCLUSIVE:
|
|
return "EX";
|
|
}
|
|
return "??";
|
|
}
|
|
|
|
static const char *hflags2str(char *buf, u16 flags, unsigned long iflags)
|
|
{
|
|
char *p = buf;
|
|
if (flags & LM_FLAG_TRY)
|
|
*p++ = 't';
|
|
if (flags & LM_FLAG_TRY_1CB)
|
|
*p++ = 'T';
|
|
if (flags & LM_FLAG_NOEXP)
|
|
*p++ = 'e';
|
|
if (flags & LM_FLAG_ANY)
|
|
*p++ = 'A';
|
|
if (flags & LM_FLAG_PRIORITY)
|
|
*p++ = 'p';
|
|
if (flags & LM_FLAG_NODE_SCOPE)
|
|
*p++ = 'n';
|
|
if (flags & GL_ASYNC)
|
|
*p++ = 'a';
|
|
if (flags & GL_EXACT)
|
|
*p++ = 'E';
|
|
if (flags & GL_NOCACHE)
|
|
*p++ = 'c';
|
|
if (test_bit(HIF_HOLDER, &iflags))
|
|
*p++ = 'H';
|
|
if (test_bit(HIF_WAIT, &iflags))
|
|
*p++ = 'W';
|
|
if (test_bit(HIF_MAY_DEMOTE, &iflags))
|
|
*p++ = 'D';
|
|
if (flags & GL_SKIP)
|
|
*p++ = 's';
|
|
*p = 0;
|
|
return buf;
|
|
}
|
|
|
|
/**
|
|
* dump_holder - print information about a glock holder
|
|
* @seq: the seq_file struct
|
|
* @gh: the glock holder
|
|
* @fs_id_buf: pointer to file system id (if requested)
|
|
*
|
|
*/
|
|
|
|
static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh,
|
|
const char *fs_id_buf)
|
|
{
|
|
struct task_struct *gh_owner = NULL;
|
|
char flags_buf[32];
|
|
|
|
rcu_read_lock();
|
|
if (gh->gh_owner_pid)
|
|
gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
|
|
gfs2_print_dbg(seq, "%s H: s:%s f:%s e:%d p:%ld [%s] %pS\n",
|
|
fs_id_buf, state2str(gh->gh_state),
|
|
hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags),
|
|
gh->gh_error,
|
|
gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1,
|
|
gh_owner ? gh_owner->comm : "(ended)",
|
|
(void *)gh->gh_ip);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
|
|
{
|
|
const unsigned long *gflags = &gl->gl_flags;
|
|
char *p = buf;
|
|
|
|
if (test_bit(GLF_LOCK, gflags))
|
|
*p++ = 'l';
|
|
if (test_bit(GLF_DEMOTE, gflags))
|
|
*p++ = 'D';
|
|
if (test_bit(GLF_PENDING_DEMOTE, gflags))
|
|
*p++ = 'd';
|
|
if (test_bit(GLF_DEMOTE_IN_PROGRESS, gflags))
|
|
*p++ = 'p';
|
|
if (test_bit(GLF_DIRTY, gflags))
|
|
*p++ = 'y';
|
|
if (test_bit(GLF_LFLUSH, gflags))
|
|
*p++ = 'f';
|
|
if (test_bit(GLF_INVALIDATE_IN_PROGRESS, gflags))
|
|
*p++ = 'i';
|
|
if (test_bit(GLF_REPLY_PENDING, gflags))
|
|
*p++ = 'r';
|
|
if (test_bit(GLF_INITIAL, gflags))
|
|
*p++ = 'I';
|
|
if (test_bit(GLF_FROZEN, gflags))
|
|
*p++ = 'F';
|
|
if (!list_empty(&gl->gl_holders))
|
|
*p++ = 'q';
|
|
if (test_bit(GLF_LRU, gflags))
|
|
*p++ = 'L';
|
|
if (gl->gl_object)
|
|
*p++ = 'o';
|
|
if (test_bit(GLF_BLOCKING, gflags))
|
|
*p++ = 'b';
|
|
if (test_bit(GLF_PENDING_DELETE, gflags))
|
|
*p++ = 'P';
|
|
if (test_bit(GLF_FREEING, gflags))
|
|
*p++ = 'x';
|
|
if (test_bit(GLF_INSTANTIATE_NEEDED, gflags))
|
|
*p++ = 'n';
|
|
if (test_bit(GLF_INSTANTIATE_IN_PROG, gflags))
|
|
*p++ = 'N';
|
|
*p = 0;
|
|
return buf;
|
|
}
|
|
|
|
/**
|
|
* gfs2_dump_glock - print information about a glock
|
|
* @seq: The seq_file struct
|
|
* @gl: the glock
|
|
* @fsid: If true, also dump the file system id
|
|
*
|
|
* The file format is as follows:
|
|
* One line per object, capital letters are used to indicate objects
|
|
* G = glock, I = Inode, R = rgrp, H = holder. Glocks are not indented,
|
|
* other objects are indented by a single space and follow the glock to
|
|
* which they are related. Fields are indicated by lower case letters
|
|
* followed by a colon and the field value, except for strings which are in
|
|
* [] so that its possible to see if they are composed of spaces for
|
|
* example. The field's are n = number (id of the object), f = flags,
|
|
* t = type, s = state, r = refcount, e = error, p = pid.
|
|
*
|
|
*/
|
|
|
|
void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
|
|
{
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
unsigned long long dtime;
|
|
const struct gfs2_holder *gh;
|
|
char gflags_buf[32];
|
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
|
|
char fs_id_buf[sizeof(sdp->sd_fsname) + 7];
|
|
unsigned long nrpages = 0;
|
|
|
|
if (gl->gl_ops->go_flags & GLOF_ASPACE) {
|
|
struct address_space *mapping = gfs2_glock2aspace(gl);
|
|
|
|
nrpages = mapping->nrpages;
|
|
}
|
|
memset(fs_id_buf, 0, sizeof(fs_id_buf));
|
|
if (fsid && sdp) /* safety precaution */
|
|
sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
|
|
dtime = jiffies - gl->gl_demote_time;
|
|
dtime *= 1000000/HZ; /* demote time in uSec */
|
|
if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
|
|
dtime = 0;
|
|
gfs2_print_dbg(seq, "%sG: s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d "
|
|
"v:%d r:%d m:%ld p:%lu\n",
|
|
fs_id_buf, state2str(gl->gl_state),
|
|
gl->gl_name.ln_type,
|
|
(unsigned long long)gl->gl_name.ln_number,
|
|
gflags2str(gflags_buf, gl),
|
|
state2str(gl->gl_target),
|
|
state2str(gl->gl_demote_state), dtime,
|
|
atomic_read(&gl->gl_ail_count),
|
|
atomic_read(&gl->gl_revokes),
|
|
(int)gl->gl_lockref.count, gl->gl_hold_time, nrpages);
|
|
|
|
list_for_each_entry(gh, &gl->gl_holders, gh_list)
|
|
dump_holder(seq, gh, fs_id_buf);
|
|
|
|
if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
|
|
glops->go_dump(seq, gl, fs_id_buf);
|
|
}
|
|
|
|
static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
|
|
{
|
|
struct gfs2_glock *gl = iter_ptr;
|
|
|
|
seq_printf(seq, "G: n:%u/%llx rtt:%llu/%llu rttb:%llu/%llu irt:%llu/%llu dcnt: %llu qcnt: %llu\n",
|
|
gl->gl_name.ln_type,
|
|
(unsigned long long)gl->gl_name.ln_number,
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTT],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTVAR],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTB],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SRTTVARB],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SIRT],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_SIRTVAR],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_DCOUNT],
|
|
(unsigned long long)gl->gl_stats.stats[GFS2_LKS_QCOUNT]);
|
|
return 0;
|
|
}
|
|
|
|
static const char *gfs2_gltype[] = {
|
|
"type",
|
|
"reserved",
|
|
"nondisk",
|
|
"inode",
|
|
"rgrp",
|
|
"meta",
|
|
"iopen",
|
|
"flock",
|
|
"plock",
|
|
"quota",
|
|
"journal",
|
|
};
|
|
|
|
static const char *gfs2_stype[] = {
|
|
[GFS2_LKS_SRTT] = "srtt",
|
|
[GFS2_LKS_SRTTVAR] = "srttvar",
|
|
[GFS2_LKS_SRTTB] = "srttb",
|
|
[GFS2_LKS_SRTTVARB] = "srttvarb",
|
|
[GFS2_LKS_SIRT] = "sirt",
|
|
[GFS2_LKS_SIRTVAR] = "sirtvar",
|
|
[GFS2_LKS_DCOUNT] = "dlm",
|
|
[GFS2_LKS_QCOUNT] = "queue",
|
|
};
|
|
|
|
#define GFS2_NR_SBSTATS (ARRAY_SIZE(gfs2_gltype) * ARRAY_SIZE(gfs2_stype))
|
|
|
|
static int gfs2_sbstats_seq_show(struct seq_file *seq, void *iter_ptr)
|
|
{
|
|
struct gfs2_sbd *sdp = seq->private;
|
|
loff_t pos = *(loff_t *)iter_ptr;
|
|
unsigned index = pos >> 3;
|
|
unsigned subindex = pos & 0x07;
|
|
int i;
|
|
|
|
if (index == 0 && subindex != 0)
|
|
return 0;
|
|
|
|
seq_printf(seq, "%-10s %8s:", gfs2_gltype[index],
|
|
(index == 0) ? "cpu": gfs2_stype[subindex]);
|
|
|
|
for_each_possible_cpu(i) {
|
|
const struct gfs2_pcpu_lkstats *lkstats = per_cpu_ptr(sdp->sd_lkstats, i);
|
|
|
|
if (index == 0)
|
|
seq_printf(seq, " %15u", i);
|
|
else
|
|
seq_printf(seq, " %15llu", (unsigned long long)lkstats->
|
|
lkstats[index - 1].stats[subindex]);
|
|
}
|
|
seq_putc(seq, '\n');
|
|
return 0;
|
|
}
|
|
|
|
int __init gfs2_glock_init(void)
|
|
{
|
|
int i, ret;
|
|
|
|
ret = rhashtable_init(&gl_hash_table, &ht_parms);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
|
|
WQ_HIGHPRI | WQ_FREEZABLE, 0);
|
|
if (!glock_workqueue) {
|
|
rhashtable_destroy(&gl_hash_table);
|
|
return -ENOMEM;
|
|
}
|
|
gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
|
|
WQ_MEM_RECLAIM | WQ_FREEZABLE,
|
|
0);
|
|
if (!gfs2_delete_workqueue) {
|
|
destroy_workqueue(glock_workqueue);
|
|
rhashtable_destroy(&gl_hash_table);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
ret = register_shrinker(&glock_shrinker);
|
|
if (ret) {
|
|
destroy_workqueue(gfs2_delete_workqueue);
|
|
destroy_workqueue(glock_workqueue);
|
|
rhashtable_destroy(&gl_hash_table);
|
|
return ret;
|
|
}
|
|
|
|
for (i = 0; i < GLOCK_WAIT_TABLE_SIZE; i++)
|
|
init_waitqueue_head(glock_wait_table + i);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void gfs2_glock_exit(void)
|
|
{
|
|
unregister_shrinker(&glock_shrinker);
|
|
rhashtable_destroy(&gl_hash_table);
|
|
destroy_workqueue(glock_workqueue);
|
|
destroy_workqueue(gfs2_delete_workqueue);
|
|
}
|
|
|
|
static void gfs2_glock_iter_next(struct gfs2_glock_iter *gi, loff_t n)
|
|
{
|
|
struct gfs2_glock *gl = gi->gl;
|
|
|
|
if (gl) {
|
|
if (n == 0)
|
|
return;
|
|
if (!lockref_put_not_zero(&gl->gl_lockref))
|
|
gfs2_glock_queue_put(gl);
|
|
}
|
|
for (;;) {
|
|
gl = rhashtable_walk_next(&gi->hti);
|
|
if (IS_ERR_OR_NULL(gl)) {
|
|
if (gl == ERR_PTR(-EAGAIN)) {
|
|
n = 1;
|
|
continue;
|
|
}
|
|
gl = NULL;
|
|
break;
|
|
}
|
|
if (gl->gl_name.ln_sbd != gi->sdp)
|
|
continue;
|
|
if (n <= 1) {
|
|
if (!lockref_get_not_dead(&gl->gl_lockref))
|
|
continue;
|
|
break;
|
|
} else {
|
|
if (__lockref_is_dead(&gl->gl_lockref))
|
|
continue;
|
|
n--;
|
|
}
|
|
}
|
|
gi->gl = gl;
|
|
}
|
|
|
|
static void *gfs2_glock_seq_start(struct seq_file *seq, loff_t *pos)
|
|
__acquires(RCU)
|
|
{
|
|
struct gfs2_glock_iter *gi = seq->private;
|
|
loff_t n;
|
|
|
|
/*
|
|
* We can either stay where we are, skip to the next hash table
|
|
* entry, or start from the beginning.
|
|
*/
|
|
if (*pos < gi->last_pos) {
|
|
rhashtable_walk_exit(&gi->hti);
|
|
rhashtable_walk_enter(&gl_hash_table, &gi->hti);
|
|
n = *pos + 1;
|
|
} else {
|
|
n = *pos - gi->last_pos;
|
|
}
|
|
|
|
rhashtable_walk_start(&gi->hti);
|
|
|
|
gfs2_glock_iter_next(gi, n);
|
|
gi->last_pos = *pos;
|
|
return gi->gl;
|
|
}
|
|
|
|
static void *gfs2_glock_seq_next(struct seq_file *seq, void *iter_ptr,
|
|
loff_t *pos)
|
|
{
|
|
struct gfs2_glock_iter *gi = seq->private;
|
|
|
|
(*pos)++;
|
|
gi->last_pos = *pos;
|
|
gfs2_glock_iter_next(gi, 1);
|
|
return gi->gl;
|
|
}
|
|
|
|
static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
|
|
__releases(RCU)
|
|
{
|
|
struct gfs2_glock_iter *gi = seq->private;
|
|
|
|
rhashtable_walk_stop(&gi->hti);
|
|
}
|
|
|
|
static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
|
|
{
|
|
dump_glock(seq, iter_ptr, false);
|
|
return 0;
|
|
}
|
|
|
|
static void *gfs2_sbstats_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
preempt_disable();
|
|
if (*pos >= GFS2_NR_SBSTATS)
|
|
return NULL;
|
|
return pos;
|
|
}
|
|
|
|
static void *gfs2_sbstats_seq_next(struct seq_file *seq, void *iter_ptr,
|
|
loff_t *pos)
|
|
{
|
|
(*pos)++;
|
|
if (*pos >= GFS2_NR_SBSTATS)
|
|
return NULL;
|
|
return pos;
|
|
}
|
|
|
|
static void gfs2_sbstats_seq_stop(struct seq_file *seq, void *iter_ptr)
|
|
{
|
|
preempt_enable();
|
|
}
|
|
|
|
static const struct seq_operations gfs2_glock_seq_ops = {
|
|
.start = gfs2_glock_seq_start,
|
|
.next = gfs2_glock_seq_next,
|
|
.stop = gfs2_glock_seq_stop,
|
|
.show = gfs2_glock_seq_show,
|
|
};
|
|
|
|
static const struct seq_operations gfs2_glstats_seq_ops = {
|
|
.start = gfs2_glock_seq_start,
|
|
.next = gfs2_glock_seq_next,
|
|
.stop = gfs2_glock_seq_stop,
|
|
.show = gfs2_glstats_seq_show,
|
|
};
|
|
|
|
static const struct seq_operations gfs2_sbstats_sops = {
|
|
.start = gfs2_sbstats_seq_start,
|
|
.next = gfs2_sbstats_seq_next,
|
|
.stop = gfs2_sbstats_seq_stop,
|
|
.show = gfs2_sbstats_seq_show,
|
|
};
|
|
|
|
#define GFS2_SEQ_GOODSIZE min(PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER, 65536UL)
|
|
|
|
static int __gfs2_glocks_open(struct inode *inode, struct file *file,
|
|
const struct seq_operations *ops)
|
|
{
|
|
int ret = seq_open_private(file, ops, sizeof(struct gfs2_glock_iter));
|
|
if (ret == 0) {
|
|
struct seq_file *seq = file->private_data;
|
|
struct gfs2_glock_iter *gi = seq->private;
|
|
|
|
gi->sdp = inode->i_private;
|
|
seq->buf = kmalloc(GFS2_SEQ_GOODSIZE, GFP_KERNEL | __GFP_NOWARN);
|
|
if (seq->buf)
|
|
seq->size = GFS2_SEQ_GOODSIZE;
|
|
/*
|
|
* Initially, we are "before" the first hash table entry; the
|
|
* first call to rhashtable_walk_next gets us the first entry.
|
|
*/
|
|
gi->last_pos = -1;
|
|
gi->gl = NULL;
|
|
rhashtable_walk_enter(&gl_hash_table, &gi->hti);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int gfs2_glocks_open(struct inode *inode, struct file *file)
|
|
{
|
|
return __gfs2_glocks_open(inode, file, &gfs2_glock_seq_ops);
|
|
}
|
|
|
|
static int gfs2_glocks_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *seq = file->private_data;
|
|
struct gfs2_glock_iter *gi = seq->private;
|
|
|
|
if (gi->gl)
|
|
gfs2_glock_put(gi->gl);
|
|
rhashtable_walk_exit(&gi->hti);
|
|
return seq_release_private(inode, file);
|
|
}
|
|
|
|
static int gfs2_glstats_open(struct inode *inode, struct file *file)
|
|
{
|
|
return __gfs2_glocks_open(inode, file, &gfs2_glstats_seq_ops);
|
|
}
|
|
|
|
static const struct file_operations gfs2_glocks_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = gfs2_glocks_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = gfs2_glocks_release,
|
|
};
|
|
|
|
static const struct file_operations gfs2_glstats_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = gfs2_glstats_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = gfs2_glocks_release,
|
|
};
|
|
|
|
DEFINE_SEQ_ATTRIBUTE(gfs2_sbstats);
|
|
|
|
void gfs2_create_debugfs_file(struct gfs2_sbd *sdp)
|
|
{
|
|
sdp->debugfs_dir = debugfs_create_dir(sdp->sd_table_name, gfs2_root);
|
|
|
|
debugfs_create_file("glocks", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
|
|
&gfs2_glocks_fops);
|
|
|
|
debugfs_create_file("glstats", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
|
|
&gfs2_glstats_fops);
|
|
|
|
debugfs_create_file("sbstats", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp,
|
|
&gfs2_sbstats_fops);
|
|
}
|
|
|
|
void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp)
|
|
{
|
|
debugfs_remove_recursive(sdp->debugfs_dir);
|
|
sdp->debugfs_dir = NULL;
|
|
}
|
|
|
|
void gfs2_register_debugfs(void)
|
|
{
|
|
gfs2_root = debugfs_create_dir("gfs2", NULL);
|
|
}
|
|
|
|
void gfs2_unregister_debugfs(void)
|
|
{
|
|
debugfs_remove(gfs2_root);
|
|
gfs2_root = NULL;
|
|
}
|