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2548 lines
65 KiB
2548 lines
65 KiB
// 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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|
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
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|
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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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|
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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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|
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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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|
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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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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 its ok to grant a new lock |
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* @gl: The glock |
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* @gh: The lock request which we wish to grant |
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* |
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* Returns: true if its ok to grant the lock |
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*/ |
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static inline int may_grant(const struct gfs2_glock *gl, const struct gfs2_holder *gh) |
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{ |
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const struct gfs2_holder *gh_head = list_first_entry(&gl->gl_holders, const struct gfs2_holder, gh_list); |
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|
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if (gh != gh_head) { |
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/** |
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* Here we make a special exception to grant holders who agree |
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* to share the EX lock with other holders who also have the |
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* bit set. If the original holder has the LM_FLAG_NODE_SCOPE bit |
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* is set, we grant more holders with the bit set. |
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*/ |
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if (gh_head->gh_state == LM_ST_EXCLUSIVE && |
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(gh_head->gh_flags & LM_FLAG_NODE_SCOPE) && |
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gh->gh_state == LM_ST_EXCLUSIVE && |
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(gh->gh_flags & LM_FLAG_NODE_SCOPE)) |
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return 1; |
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if ((gh->gh_state == LM_ST_EXCLUSIVE || |
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gh_head->gh_state == LM_ST_EXCLUSIVE)) |
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return 0; |
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} |
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if (gl->gl_state == gh->gh_state) |
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return 1; |
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if (gh->gh_flags & GL_EXACT) |
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return 0; |
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if (gl->gl_state == LM_ST_EXCLUSIVE) { |
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if (gh->gh_state == LM_ST_SHARED && gh_head->gh_state == LM_ST_SHARED) |
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return 1; |
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if (gh->gh_state == LM_ST_DEFERRED && gh_head->gh_state == LM_ST_DEFERRED) |
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return 1; |
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} |
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if (gl->gl_state != LM_ST_UNLOCKED && (gh->gh_flags & LM_FLAG_ANY)) |
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return 1; |
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return 0; |
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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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/** |
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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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|
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list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { |
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if (test_bit(HIF_HOLDER, &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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/** |
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* do_promote - promote as many requests as possible on the current queue |
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* @gl: The glock |
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* |
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* Returns: 1 if there is a blocked holder at the head of the list, or 2 |
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* if a type specific operation is underway. |
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*/ |
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static int do_promote(struct gfs2_glock *gl) |
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__releases(&gl->gl_lockref.lock) |
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__acquires(&gl->gl_lockref.lock) |
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{ |
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const struct gfs2_glock_operations *glops = gl->gl_ops; |
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struct gfs2_holder *gh, *tmp; |
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int ret; |
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restart: |
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list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { |
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if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
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continue; |
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if (may_grant(gl, gh)) { |
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if (gh->gh_list.prev == &gl->gl_holders && |
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glops->go_lock) { |
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spin_unlock(&gl->gl_lockref.lock); |
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/* FIXME: eliminate this eventually */ |
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ret = glops->go_lock(gh); |
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spin_lock(&gl->gl_lockref.lock); |
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if (ret) { |
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if (ret == 1) |
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return 2; |
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gh->gh_error = ret; |
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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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goto restart; |
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} |
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set_bit(HIF_HOLDER, &gh->gh_iflags); |
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trace_gfs2_promote(gh, 1); |
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gfs2_holder_wake(gh); |
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goto restart; |
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} |
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set_bit(HIF_HOLDER, &gh->gh_iflags); |
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trace_gfs2_promote(gh, 0); |
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gfs2_holder_wake(gh); |
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continue; |
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} |
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if (gh->gh_list.prev == &gl->gl_holders) |
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return 1; |
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do_error(gl, 0); |
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break; |
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} |
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return 0; |
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} |
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|
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/** |
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* find_first_waiter - find the first gh that's waiting for the glock |
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* @gl: the glock |
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*/ |
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|
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static inline struct gfs2_holder *find_first_waiter(const struct gfs2_glock *gl) |
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{ |
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struct gfs2_holder *gh; |
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|
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list_for_each_entry(gh, &gl->gl_holders, 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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/** |
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* state_change - record that the glock is now in a different state |
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* @gl: the glock |
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* @new_state: the new state |
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*/ |
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|
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static void state_change(struct gfs2_glock *gl, unsigned int new_state) |
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{ |
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int held1, held2; |
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|
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held1 = (gl->gl_state != LM_ST_UNLOCKED); |
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held2 = (new_state != LM_ST_UNLOCKED); |
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|
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if (held1 != held2) { |
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GLOCK_BUG_ON(gl, __lockref_is_dead(&gl->gl_lockref)); |
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if (held2) |
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gl->gl_lockref.count++; |
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else |
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gl->gl_lockref.count--; |
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} |
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if (new_state != gl->gl_target) |
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/* shorten our minimum hold time */ |
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gl->gl_hold_time = max(gl->gl_hold_time - GL_GLOCK_HOLD_DECR, |
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GL_GLOCK_MIN_HOLD); |
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gl->gl_state = new_state; |
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gl->gl_tchange = jiffies; |
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} |
|
|
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static void gfs2_set_demote(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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set_bit(GLF_DEMOTE, &gl->gl_flags); |
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smp_mb(); |
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wake_up(&sdp->sd_async_glock_wait); |
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} |
|
|
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static void gfs2_demote_wake(struct gfs2_glock *gl) |
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{ |
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gl->gl_demote_state = LM_ST_EXCLUSIVE; |
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clear_bit(GLF_DEMOTE, &gl->gl_flags); |
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smp_mb__after_atomic(); |
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wake_up_bit(&gl->gl_flags, GLF_DEMOTE); |
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} |
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|
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/** |
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* finish_xmote - The DLM has replied to one of our lock requests |
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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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*/ |
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|
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static void finish_xmote(struct gfs2_glock *gl, unsigned int ret) |
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{ |
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const struct gfs2_glock_operations *glops = gl->gl_ops; |
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struct gfs2_holder *gh; |
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unsigned state = ret & LM_OUT_ST_MASK; |
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int rv; |
|
|
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spin_lock(&gl->gl_lockref.lock); |
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trace_gfs2_glock_state_change(gl, state); |
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state_change(gl, state); |
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gh = find_first_waiter(gl); |
|
|
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/* Demote to UN request arrived during demote to SH or DF */ |
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if (test_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags) && |
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state != LM_ST_UNLOCKED && gl->gl_demote_state == LM_ST_UNLOCKED) |
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gl->gl_target = LM_ST_UNLOCKED; |
|
|
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/* 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); |
|
} |
|
|
|
/** |
|
* find_first_holder - find the first "holder" gh |
|
* @gl: the glock |
|
*/ |
|
|
|
static inline struct gfs2_holder *find_first_holder(const struct gfs2_glock *gl) |
|
{ |
|
struct gfs2_holder *gh; |
|
|
|
if (!list_empty(&gl->gl_holders)) { |
|
gh = list_first_entry(&gl->gl_holders, struct gfs2_holder, gh_list); |
|
if (test_bit(HIF_HOLDER, &gh->gh_iflags)) |
|
return gh; |
|
} |
|
return NULL; |
|
} |
|
|
|
/** |
|
* 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); |
|
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 = 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) |
|
{ |
|
INIT_LIST_HEAD(&gh->gh_list); |
|
gh->gh_gl = gl; |
|
gh->gh_ip = _RET_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)) |
|
try_futile = !may_grant(gl, 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))) |
|
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; |
|
} |
|
|
|
/** |
|
* 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; |
|
struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; |
|
unsigned delay = 0; |
|
int fast_path = 0; |
|
|
|
spin_lock(&gl->gl_lockref.lock); |
|
/* |
|
* 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); |
|
} |
|
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); |
|
if (list_empty(&gl->gl_holders) && |
|
!test_bit(GLF_PENDING_DEMOTE, &gl->gl_flags) && |
|
!test_bit(GLF_DEMOTE, &gl->gl_flags)) |
|
fast_path = 1; |
|
|
|
if (!test_bit(GLF_LFLUSH, &gl->gl_flags) && demote_ok(gl)) |
|
gfs2_glock_add_to_lru(gl); |
|
|
|
trace_gfs2_glock_queue(gh, 0); |
|
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); |
|
} |
|
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; |
|
} |
|
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 && |
|
lockref_get_not_dead(&gl->gl_lockref)) |
|
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_sync(&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); |
|
} |
|
} |
|
gfs2_glock_queue_work(gl, 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)) { |
|
gfs2_glock_put(gl); |
|
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 (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'; |
|
*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'; |
|
*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; |
|
}
|
|
|