forked from luck/tmp_suning_uos_patched
7d308590ae
lm_interface.h has a few out of the tree clients such as GFS1 and userland tools. Right now, these clients keeps a copy of the file in their build tree that can go out of sync. Move lm_interface.h to include/linux, export it to userland and clean up fs/gfs2 to use the new location. Signed-off-by: Fabio M. Di Nitto <fabbione@ubuntu.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2232 lines
50 KiB
C
2232 lines
50 KiB
C
/*
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* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
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* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
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*
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* This copyrighted material is made available to anyone wishing to use,
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* modify, copy, or redistribute it subject to the terms and conditions
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* of the GNU General Public License version 2.
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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/completion.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/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/lm_interface.h>
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#include <asm/uaccess.h>
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#include "gfs2.h"
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#include "incore.h"
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#include "glock.h"
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#include "glops.h"
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#include "inode.h"
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#include "lm.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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struct greedy {
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struct gfs2_holder gr_gh;
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struct work_struct gr_work;
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};
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struct gfs2_gl_hash_bucket {
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struct hlist_head hb_list;
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};
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typedef void (*glock_examiner) (struct gfs2_glock * gl);
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static int gfs2_dump_lockstate(struct gfs2_sbd *sdp);
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static int dump_glock(struct gfs2_glock *gl);
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static int dump_inode(struct gfs2_inode *ip);
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#define GFS2_GL_HASH_SHIFT 15
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#define GFS2_GL_HASH_SIZE (1 << GFS2_GL_HASH_SHIFT)
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#define GFS2_GL_HASH_MASK (GFS2_GL_HASH_SIZE - 1)
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static struct gfs2_gl_hash_bucket gl_hash_table[GFS2_GL_HASH_SIZE];
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/*
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* Despite what you might think, the numbers below are not arbitrary :-)
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* They are taken from the ipv4 routing hash code, which is well tested
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* and thus should be nearly optimal. Later on we might tweek the numbers
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* but for now this should be fine.
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*
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* The reason for putting the locks in a separate array from the list heads
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* is that we can have fewer locks than list heads and save memory. We use
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* the same hash function for both, but with a different hash mask.
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*/
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#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
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defined(CONFIG_PROVE_LOCKING)
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#ifdef CONFIG_LOCKDEP
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# define GL_HASH_LOCK_SZ 256
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#else
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# if NR_CPUS >= 32
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# define GL_HASH_LOCK_SZ 4096
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# elif NR_CPUS >= 16
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# define GL_HASH_LOCK_SZ 2048
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# elif NR_CPUS >= 8
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# define GL_HASH_LOCK_SZ 1024
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# elif NR_CPUS >= 4
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# define GL_HASH_LOCK_SZ 512
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# else
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# define GL_HASH_LOCK_SZ 256
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# endif
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#endif
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/* We never want more locks than chains */
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#if GFS2_GL_HASH_SIZE < GL_HASH_LOCK_SZ
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# undef GL_HASH_LOCK_SZ
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# define GL_HASH_LOCK_SZ GFS2_GL_HASH_SIZE
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#endif
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static rwlock_t gl_hash_locks[GL_HASH_LOCK_SZ];
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static inline rwlock_t *gl_lock_addr(unsigned int x)
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{
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return &gl_hash_locks[x & (GL_HASH_LOCK_SZ-1)];
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}
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#else /* not SMP, so no spinlocks required */
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static inline rwlock_t *gl_lock_addr(x)
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{
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return NULL;
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}
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#endif
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/**
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* relaxed_state_ok - is a requested lock compatible with the current lock mode?
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* @actual: the current state of the lock
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* @requested: the lock state that was requested by the caller
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* @flags: the modifier flags passed in by the caller
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*
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* Returns: 1 if the locks are compatible, 0 otherwise
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*/
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static inline int relaxed_state_ok(unsigned int actual, unsigned requested,
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int flags)
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{
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if (actual == requested)
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return 1;
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if (flags & GL_EXACT)
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return 0;
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if (actual == LM_ST_EXCLUSIVE && requested == LM_ST_SHARED)
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return 1;
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if (actual != LM_ST_UNLOCKED && (flags & LM_FLAG_ANY))
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return 1;
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return 0;
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}
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/**
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* gl_hash() - Turn glock number into hash bucket number
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* @lock: The glock number
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*
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* Returns: The number of the corresponding hash bucket
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*/
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static unsigned int gl_hash(const struct gfs2_sbd *sdp,
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const struct lm_lockname *name)
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{
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unsigned int h;
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h = jhash(&name->ln_number, sizeof(u64), 0);
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h = jhash(&name->ln_type, sizeof(unsigned int), h);
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h = jhash(&sdp, sizeof(struct gfs2_sbd *), h);
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h &= GFS2_GL_HASH_MASK;
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return h;
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}
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/**
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* glock_free() - Perform a few checks and then release struct gfs2_glock
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* @gl: The glock to release
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*
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* Also calls lock module to release its internal structure for this glock.
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*
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*/
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static void glock_free(struct gfs2_glock *gl)
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{
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struct gfs2_sbd *sdp = gl->gl_sbd;
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struct inode *aspace = gl->gl_aspace;
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gfs2_lm_put_lock(sdp, gl->gl_lock);
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if (aspace)
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gfs2_aspace_put(aspace);
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kmem_cache_free(gfs2_glock_cachep, gl);
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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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atomic_inc(&gl->gl_ref);
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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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int gfs2_glock_put(struct gfs2_glock *gl)
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{
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int rv = 0;
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struct gfs2_sbd *sdp = gl->gl_sbd;
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write_lock(gl_lock_addr(gl->gl_hash));
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if (atomic_dec_and_test(&gl->gl_ref)) {
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hlist_del(&gl->gl_list);
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write_unlock(gl_lock_addr(gl->gl_hash));
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BUG_ON(spin_is_locked(&gl->gl_spin));
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gfs2_assert(sdp, gl->gl_state == LM_ST_UNLOCKED);
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gfs2_assert(sdp, list_empty(&gl->gl_reclaim));
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gfs2_assert(sdp, list_empty(&gl->gl_holders));
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gfs2_assert(sdp, list_empty(&gl->gl_waiters1));
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gfs2_assert(sdp, list_empty(&gl->gl_waiters2));
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gfs2_assert(sdp, list_empty(&gl->gl_waiters3));
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glock_free(gl);
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rv = 1;
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goto out;
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}
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write_unlock(gl_lock_addr(gl->gl_hash));
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out:
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return rv;
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}
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/**
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* queue_empty - check to see if a glock's queue is empty
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* @gl: the glock
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* @head: the head of the queue to check
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*
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* This function protects the list in the event that a process already
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* has a holder on the list and is adding a second holder for itself.
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* The glmutex lock is what generally prevents processes from working
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* on the same glock at once, but the special case of adding a second
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* holder for yourself ("recursive" locking) doesn't involve locking
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* glmutex, making the spin lock necessary.
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*
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* Returns: 1 if the queue is empty
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*/
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static inline int queue_empty(struct gfs2_glock *gl, struct list_head *head)
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{
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int empty;
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spin_lock(&gl->gl_spin);
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empty = list_empty(head);
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spin_unlock(&gl->gl_spin);
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return empty;
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}
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/**
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* search_bucket() - Find struct gfs2_glock by lock number
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* @bucket: the bucket to search
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* @name: The lock name
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*
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* Returns: NULL, or the struct gfs2_glock with the requested number
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*/
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static struct gfs2_glock *search_bucket(unsigned int hash,
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const struct gfs2_sbd *sdp,
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const struct lm_lockname *name)
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{
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struct gfs2_glock *gl;
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struct hlist_node *h;
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hlist_for_each_entry(gl, h, &gl_hash_table[hash].hb_list, gl_list) {
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if (!lm_name_equal(&gl->gl_name, name))
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continue;
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if (gl->gl_sbd != sdp)
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continue;
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atomic_inc(&gl->gl_ref);
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return gl;
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}
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return NULL;
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}
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/**
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* gfs2_glock_find() - Find glock by lock number
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* @sdp: The GFS2 superblock
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* @name: The lock name
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*
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* Returns: NULL, or the struct gfs2_glock with the requested number
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*/
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static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp,
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const struct lm_lockname *name)
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{
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unsigned int hash = gl_hash(sdp, name);
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struct gfs2_glock *gl;
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read_lock(gl_lock_addr(hash));
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gl = search_bucket(hash, sdp, name);
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read_unlock(gl_lock_addr(hash));
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return gl;
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}
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/**
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* gfs2_glock_get() - Get a glock, or create one if one doesn't exist
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* @sdp: The GFS2 superblock
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* @number: the lock number
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* @glops: The glock_operations to use
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* @create: If 0, don't create the glock if it doesn't exist
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* @glp: the glock is returned here
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*
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* This does not lock a glock, just finds/creates structures for one.
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*
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* Returns: errno
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*/
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int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
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const struct gfs2_glock_operations *glops, int create,
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struct gfs2_glock **glp)
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{
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struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type };
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struct gfs2_glock *gl, *tmp;
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unsigned int hash = gl_hash(sdp, &name);
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int error;
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read_lock(gl_lock_addr(hash));
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gl = search_bucket(hash, sdp, &name);
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read_unlock(gl_lock_addr(hash));
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if (gl || !create) {
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*glp = gl;
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return 0;
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}
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gl = kmem_cache_alloc(gfs2_glock_cachep, GFP_KERNEL);
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if (!gl)
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return -ENOMEM;
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gl->gl_flags = 0;
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gl->gl_name = name;
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atomic_set(&gl->gl_ref, 1);
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gl->gl_state = LM_ST_UNLOCKED;
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gl->gl_hash = hash;
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gl->gl_owner = NULL;
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gl->gl_ip = 0;
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gl->gl_ops = glops;
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gl->gl_req_gh = NULL;
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gl->gl_req_bh = NULL;
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gl->gl_vn = 0;
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gl->gl_stamp = jiffies;
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gl->gl_object = NULL;
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gl->gl_sbd = sdp;
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gl->gl_aspace = NULL;
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lops_init_le(&gl->gl_le, &gfs2_glock_lops);
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/* If this glock protects actual on-disk data or metadata blocks,
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create a VFS inode to manage the pages/buffers holding them. */
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if (glops == &gfs2_inode_glops || glops == &gfs2_rgrp_glops) {
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gl->gl_aspace = gfs2_aspace_get(sdp);
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if (!gl->gl_aspace) {
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error = -ENOMEM;
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goto fail;
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}
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}
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error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock);
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if (error)
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goto fail_aspace;
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write_lock(gl_lock_addr(hash));
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tmp = search_bucket(hash, sdp, &name);
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if (tmp) {
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write_unlock(gl_lock_addr(hash));
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glock_free(gl);
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gl = tmp;
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} else {
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hlist_add_head(&gl->gl_list, &gl_hash_table[hash].hb_list);
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write_unlock(gl_lock_addr(hash));
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}
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*glp = gl;
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return 0;
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fail_aspace:
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if (gl->gl_aspace)
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gfs2_aspace_put(gl->gl_aspace);
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fail:
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kmem_cache_free(gfs2_glock_cachep, gl);
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return error;
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}
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/**
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* gfs2_holder_init - initialize a struct gfs2_holder in the default way
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* @gl: the glock
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* @state: the state we're requesting
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* @flags: the modifier flags
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* @gh: the holder structure
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*
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*/
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void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state, unsigned flags,
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struct gfs2_holder *gh)
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{
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INIT_LIST_HEAD(&gh->gh_list);
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gh->gh_gl = gl;
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gh->gh_ip = (unsigned long)__builtin_return_address(0);
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gh->gh_owner = current;
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gh->gh_state = state;
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gh->gh_flags = flags;
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gh->gh_error = 0;
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gh->gh_iflags = 0;
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init_completion(&gh->gh_wait);
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if (gh->gh_state == LM_ST_EXCLUSIVE)
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gh->gh_flags |= GL_LOCAL_EXCL;
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gfs2_glock_hold(gl);
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}
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/**
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* gfs2_holder_reinit - reinitialize a struct gfs2_holder so we can requeue it
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* @state: the state we're requesting
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* @flags: the modifier flags
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* @gh: the holder structure
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*
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* Don't mess with the glock.
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*
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*/
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void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder *gh)
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{
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gh->gh_state = state;
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gh->gh_flags = flags;
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if (gh->gh_state == LM_ST_EXCLUSIVE)
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gh->gh_flags |= GL_LOCAL_EXCL;
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gh->gh_iflags &= 1 << HIF_ALLOCED;
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gh->gh_ip = (unsigned long)__builtin_return_address(0);
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}
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/**
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* gfs2_holder_uninit - uninitialize a holder structure (drop glock reference)
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* @gh: the holder structure
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*
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*/
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void gfs2_holder_uninit(struct gfs2_holder *gh)
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{
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gfs2_glock_put(gh->gh_gl);
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gh->gh_gl = NULL;
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gh->gh_ip = 0;
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}
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/**
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* gfs2_holder_get - get a struct gfs2_holder structure
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* @gl: the glock
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* @state: the state we're requesting
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* @flags: the modifier flags
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* @gfp_flags:
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*
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* Figure out how big an impact this function has. Either:
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* 1) Replace it with a cache of structures hanging off the struct gfs2_sbd
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* 2) Leave it like it is
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*
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* Returns: the holder structure, NULL on ENOMEM
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*/
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static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl,
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unsigned int state,
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int flags, gfp_t gfp_flags)
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{
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struct gfs2_holder *gh;
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gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags);
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if (!gh)
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return NULL;
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gfs2_holder_init(gl, state, flags, gh);
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set_bit(HIF_ALLOCED, &gh->gh_iflags);
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gh->gh_ip = (unsigned long)__builtin_return_address(0);
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return gh;
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}
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|
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/**
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* gfs2_holder_put - get rid of a struct gfs2_holder structure
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* @gh: the holder structure
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*
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*/
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static void gfs2_holder_put(struct gfs2_holder *gh)
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{
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gfs2_holder_uninit(gh);
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kfree(gh);
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}
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/**
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* rq_mutex - process a mutex request in the queue
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* @gh: the glock holder
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*
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* Returns: 1 if the queue is blocked
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*/
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static int rq_mutex(struct gfs2_holder *gh)
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{
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struct gfs2_glock *gl = gh->gh_gl;
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list_del_init(&gh->gh_list);
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/* gh->gh_error never examined. */
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set_bit(GLF_LOCK, &gl->gl_flags);
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complete(&gh->gh_wait);
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return 1;
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}
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|
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/**
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* rq_promote - process a promote request in the queue
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* @gh: the glock holder
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*
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* Acquire a new inter-node lock, or change a lock state to more restrictive.
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*
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* Returns: 1 if the queue is blocked
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*/
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static int rq_promote(struct gfs2_holder *gh)
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{
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struct gfs2_glock *gl = gh->gh_gl;
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|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
if (!relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
|
|
if (list_empty(&gl->gl_holders)) {
|
|
gl->gl_req_gh = gh;
|
|
set_bit(GLF_LOCK, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (atomic_read(&sdp->sd_reclaim_count) >
|
|
gfs2_tune_get(sdp, gt_reclaim_limit) &&
|
|
!(gh->gh_flags & LM_FLAG_PRIORITY)) {
|
|
gfs2_reclaim_glock(sdp);
|
|
gfs2_reclaim_glock(sdp);
|
|
}
|
|
|
|
glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
|
|
spin_lock(&gl->gl_spin);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
if (list_empty(&gl->gl_holders)) {
|
|
set_bit(HIF_FIRST, &gh->gh_iflags);
|
|
set_bit(GLF_LOCK, &gl->gl_flags);
|
|
} else {
|
|
struct gfs2_holder *next_gh;
|
|
if (gh->gh_flags & GL_LOCAL_EXCL)
|
|
return 1;
|
|
next_gh = list_entry(gl->gl_holders.next, struct gfs2_holder,
|
|
gh_list);
|
|
if (next_gh->gh_flags & GL_LOCAL_EXCL)
|
|
return 1;
|
|
}
|
|
|
|
list_move_tail(&gh->gh_list, &gl->gl_holders);
|
|
gh->gh_error = 0;
|
|
set_bit(HIF_HOLDER, &gh->gh_iflags);
|
|
|
|
complete(&gh->gh_wait);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* rq_demote - process a demote request in the queue
|
|
* @gh: the glock holder
|
|
*
|
|
* Returns: 1 if the queue is blocked
|
|
*/
|
|
|
|
static int rq_demote(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
if (!list_empty(&gl->gl_holders))
|
|
return 1;
|
|
|
|
if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) {
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = 0;
|
|
spin_unlock(&gl->gl_spin);
|
|
if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
|
|
gfs2_holder_put(gh);
|
|
else
|
|
complete(&gh->gh_wait);
|
|
spin_lock(&gl->gl_spin);
|
|
} else {
|
|
gl->gl_req_gh = gh;
|
|
set_bit(GLF_LOCK, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (gh->gh_state == LM_ST_UNLOCKED ||
|
|
gl->gl_state != LM_ST_EXCLUSIVE)
|
|
glops->go_drop_th(gl);
|
|
else
|
|
glops->go_xmote_th(gl, gh->gh_state, gh->gh_flags);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* rq_greedy - process a queued request to drop greedy status
|
|
* @gh: the glock holder
|
|
*
|
|
* Returns: 1 if the queue is blocked
|
|
*/
|
|
|
|
static int rq_greedy(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
|
|
list_del_init(&gh->gh_list);
|
|
/* gh->gh_error never examined. */
|
|
clear_bit(GLF_GREEDY, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
gfs2_holder_uninit(gh);
|
|
kfree(container_of(gh, struct greedy, gr_gh));
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* run_queue - process holder structures on a glock
|
|
* @gl: the glock
|
|
*
|
|
*/
|
|
static void run_queue(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_holder *gh;
|
|
int blocked = 1;
|
|
|
|
for (;;) {
|
|
if (test_bit(GLF_LOCK, &gl->gl_flags))
|
|
break;
|
|
|
|
if (!list_empty(&gl->gl_waiters1)) {
|
|
gh = list_entry(gl->gl_waiters1.next,
|
|
struct gfs2_holder, gh_list);
|
|
|
|
if (test_bit(HIF_MUTEX, &gh->gh_iflags))
|
|
blocked = rq_mutex(gh);
|
|
else
|
|
gfs2_assert_warn(gl->gl_sbd, 0);
|
|
|
|
} else if (!list_empty(&gl->gl_waiters2) &&
|
|
!test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) {
|
|
gh = list_entry(gl->gl_waiters2.next,
|
|
struct gfs2_holder, gh_list);
|
|
|
|
if (test_bit(HIF_DEMOTE, &gh->gh_iflags))
|
|
blocked = rq_demote(gh);
|
|
else if (test_bit(HIF_GREEDY, &gh->gh_iflags))
|
|
blocked = rq_greedy(gh);
|
|
else
|
|
gfs2_assert_warn(gl->gl_sbd, 0);
|
|
|
|
} else if (!list_empty(&gl->gl_waiters3)) {
|
|
gh = list_entry(gl->gl_waiters3.next,
|
|
struct gfs2_holder, gh_list);
|
|
|
|
if (test_bit(HIF_PROMOTE, &gh->gh_iflags))
|
|
blocked = rq_promote(gh);
|
|
else
|
|
gfs2_assert_warn(gl->gl_sbd, 0);
|
|
|
|
} else
|
|
break;
|
|
|
|
if (blocked)
|
|
break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glmutex_lock - acquire a local lock on a glock
|
|
* @gl: the glock
|
|
*
|
|
* Gives caller exclusive access to manipulate a glock structure.
|
|
*/
|
|
|
|
static void gfs2_glmutex_lock(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_holder gh;
|
|
|
|
gfs2_holder_init(gl, 0, 0, &gh);
|
|
set_bit(HIF_MUTEX, &gh.gh_iflags);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
|
|
list_add_tail(&gh.gh_list, &gl->gl_waiters1);
|
|
} else {
|
|
gl->gl_owner = current;
|
|
gl->gl_ip = (unsigned long)__builtin_return_address(0);
|
|
complete(&gh.gh_wait);
|
|
}
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
wait_for_completion(&gh.gh_wait);
|
|
gfs2_holder_uninit(&gh);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glmutex_trylock - try to acquire a local lock on a glock
|
|
* @gl: the glock
|
|
*
|
|
* Returns: 1 if the glock is acquired
|
|
*/
|
|
|
|
static int gfs2_glmutex_trylock(struct gfs2_glock *gl)
|
|
{
|
|
int acquired = 1;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
|
|
acquired = 0;
|
|
} else {
|
|
gl->gl_owner = current;
|
|
gl->gl_ip = (unsigned long)__builtin_return_address(0);
|
|
}
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
return acquired;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glmutex_unlock - release a local lock on a glock
|
|
* @gl: the glock
|
|
*
|
|
*/
|
|
|
|
static void gfs2_glmutex_unlock(struct gfs2_glock *gl)
|
|
{
|
|
spin_lock(&gl->gl_spin);
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
gl->gl_owner = NULL;
|
|
gl->gl_ip = 0;
|
|
run_queue(gl);
|
|
BUG_ON(!spin_is_locked(&gl->gl_spin));
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
/**
|
|
* handle_callback - add a demote request to a lock's queue
|
|
* @gl: the glock
|
|
* @state: the state the caller wants us to change to
|
|
*
|
|
* Note: This may fail sliently if we are out of memory.
|
|
*/
|
|
|
|
static void handle_callback(struct gfs2_glock *gl, unsigned int state)
|
|
{
|
|
struct gfs2_holder *gh, *new_gh = NULL;
|
|
|
|
restart:
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
|
|
if (test_bit(HIF_DEMOTE, &gh->gh_iflags) &&
|
|
gl->gl_req_gh != gh) {
|
|
if (gh->gh_state != state)
|
|
gh->gh_state = LM_ST_UNLOCKED;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (new_gh) {
|
|
list_add_tail(&new_gh->gh_list, &gl->gl_waiters2);
|
|
new_gh = NULL;
|
|
} else {
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_KERNEL);
|
|
if (!new_gh)
|
|
return;
|
|
set_bit(HIF_DEMOTE, &new_gh->gh_iflags);
|
|
set_bit(HIF_DEALLOC, &new_gh->gh_iflags);
|
|
|
|
goto restart;
|
|
}
|
|
|
|
out:
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (new_gh)
|
|
gfs2_holder_put(new_gh);
|
|
}
|
|
|
|
void gfs2_glock_inode_squish(struct inode *inode)
|
|
{
|
|
struct gfs2_holder gh;
|
|
struct gfs2_glock *gl = GFS2_I(inode)->i_gl;
|
|
gfs2_holder_init(gl, LM_ST_UNLOCKED, 0, &gh);
|
|
set_bit(HIF_DEMOTE, &gh.gh_iflags);
|
|
spin_lock(&gl->gl_spin);
|
|
gfs2_assert(inode->i_sb->s_fs_info, list_empty(&gl->gl_holders));
|
|
list_add_tail(&gh.gh_list, &gl->gl_waiters2);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
wait_for_completion(&gh.gh_wait);
|
|
gfs2_holder_uninit(&gh);
|
|
}
|
|
|
|
/**
|
|
* state_change - record that the glock is now in a different state
|
|
* @gl: the glock
|
|
* @new_state the new state
|
|
*
|
|
*/
|
|
|
|
static void state_change(struct gfs2_glock *gl, unsigned int new_state)
|
|
{
|
|
int held1, held2;
|
|
|
|
held1 = (gl->gl_state != LM_ST_UNLOCKED);
|
|
held2 = (new_state != LM_ST_UNLOCKED);
|
|
|
|
if (held1 != held2) {
|
|
if (held2)
|
|
gfs2_glock_hold(gl);
|
|
else
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
gl->gl_state = new_state;
|
|
}
|
|
|
|
/**
|
|
* xmote_bh - Called after the lock module is done acquiring a lock
|
|
* @gl: The glock in question
|
|
* @ret: the int returned from the lock module
|
|
*
|
|
*/
|
|
|
|
static void xmote_bh(struct gfs2_glock *gl, unsigned int ret)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
struct gfs2_holder *gh = gl->gl_req_gh;
|
|
int prev_state = gl->gl_state;
|
|
int op_done = 1;
|
|
|
|
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
|
|
gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
|
|
gfs2_assert_warn(sdp, !(ret & LM_OUT_ASYNC));
|
|
|
|
state_change(gl, ret & LM_OUT_ST_MASK);
|
|
|
|
if (prev_state != LM_ST_UNLOCKED && !(ret & LM_OUT_CACHEABLE)) {
|
|
if (glops->go_inval)
|
|
glops->go_inval(gl, DIO_METADATA | DIO_DATA);
|
|
} else if (gl->gl_state == LM_ST_DEFERRED) {
|
|
/* We might not want to do this here.
|
|
Look at moving to the inode glops. */
|
|
if (glops->go_inval)
|
|
glops->go_inval(gl, DIO_DATA);
|
|
}
|
|
|
|
/* Deal with each possible exit condition */
|
|
|
|
if (!gh)
|
|
gl->gl_stamp = jiffies;
|
|
else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = -EIO;
|
|
spin_unlock(&gl->gl_spin);
|
|
} else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
if (gl->gl_state == gh->gh_state ||
|
|
gl->gl_state == LM_ST_UNLOCKED) {
|
|
gh->gh_error = 0;
|
|
} else {
|
|
if (gfs2_assert_warn(sdp, gh->gh_flags &
|
|
(LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1)
|
|
fs_warn(sdp, "ret = 0x%.8X\n", ret);
|
|
gh->gh_error = GLR_TRYFAILED;
|
|
}
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (ret & LM_OUT_CANCELED)
|
|
handle_callback(gl, LM_ST_UNLOCKED);
|
|
|
|
} else if (ret & LM_OUT_CANCELED) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = GLR_CANCELED;
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
} else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_move_tail(&gh->gh_list, &gl->gl_holders);
|
|
gh->gh_error = 0;
|
|
set_bit(HIF_HOLDER, &gh->gh_iflags);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
set_bit(HIF_FIRST, &gh->gh_iflags);
|
|
|
|
op_done = 0;
|
|
|
|
} else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = GLR_TRYFAILED;
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
} else {
|
|
if (gfs2_assert_withdraw(sdp, 0) == -1)
|
|
fs_err(sdp, "ret = 0x%.8X\n", ret);
|
|
}
|
|
|
|
if (glops->go_xmote_bh)
|
|
glops->go_xmote_bh(gl);
|
|
|
|
if (op_done) {
|
|
spin_lock(&gl->gl_spin);
|
|
gl->gl_req_gh = NULL;
|
|
gl->gl_req_bh = NULL;
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
gfs2_glock_put(gl);
|
|
|
|
if (gh) {
|
|
if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
|
|
gfs2_holder_put(gh);
|
|
else
|
|
complete(&gh->gh_wait);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_xmote_th - Call into the lock module to acquire or change a glock
|
|
* @gl: The glock in question
|
|
* @state: the requested state
|
|
* @flags: modifier flags to the lock call
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_xmote_th(struct gfs2_glock *gl, unsigned int state, int flags)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB |
|
|
LM_FLAG_NOEXP | LM_FLAG_ANY |
|
|
LM_FLAG_PRIORITY);
|
|
unsigned int lck_ret;
|
|
|
|
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
|
|
gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
|
|
gfs2_assert_warn(sdp, state != LM_ST_UNLOCKED);
|
|
gfs2_assert_warn(sdp, state != gl->gl_state);
|
|
|
|
if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
|
|
glops->go_sync(gl, DIO_METADATA | DIO_DATA | DIO_RELEASE);
|
|
|
|
gfs2_glock_hold(gl);
|
|
gl->gl_req_bh = xmote_bh;
|
|
|
|
lck_ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, state, lck_flags);
|
|
|
|
if (gfs2_assert_withdraw(sdp, !(lck_ret & LM_OUT_ERROR)))
|
|
return;
|
|
|
|
if (lck_ret & LM_OUT_ASYNC)
|
|
gfs2_assert_warn(sdp, lck_ret == LM_OUT_ASYNC);
|
|
else
|
|
xmote_bh(gl, lck_ret);
|
|
}
|
|
|
|
/**
|
|
* drop_bh - Called after a lock module unlock completes
|
|
* @gl: the glock
|
|
* @ret: the return status
|
|
*
|
|
* Doesn't wake up the process waiting on the struct gfs2_holder (if any)
|
|
* Doesn't drop the reference on the glock the top half took out
|
|
*
|
|
*/
|
|
|
|
static void drop_bh(struct gfs2_glock *gl, unsigned int ret)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
struct gfs2_holder *gh = gl->gl_req_gh;
|
|
|
|
clear_bit(GLF_PREFETCH, &gl->gl_flags);
|
|
|
|
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
|
|
gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
|
|
gfs2_assert_warn(sdp, !ret);
|
|
|
|
state_change(gl, LM_ST_UNLOCKED);
|
|
|
|
if (glops->go_inval)
|
|
glops->go_inval(gl, DIO_METADATA | DIO_DATA);
|
|
|
|
if (gh) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = 0;
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
if (glops->go_drop_bh)
|
|
glops->go_drop_bh(gl);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
gl->gl_req_gh = NULL;
|
|
gl->gl_req_bh = NULL;
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
gfs2_glock_put(gl);
|
|
|
|
if (gh) {
|
|
if (test_bit(HIF_DEALLOC, &gh->gh_iflags))
|
|
gfs2_holder_put(gh);
|
|
else
|
|
complete(&gh->gh_wait);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_drop_th - call into the lock module to unlock a lock
|
|
* @gl: the glock
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_drop_th(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
unsigned int ret;
|
|
|
|
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
|
|
gfs2_assert_warn(sdp, queue_empty(gl, &gl->gl_holders));
|
|
gfs2_assert_warn(sdp, gl->gl_state != LM_ST_UNLOCKED);
|
|
|
|
if (gl->gl_state == LM_ST_EXCLUSIVE && glops->go_sync)
|
|
glops->go_sync(gl, DIO_METADATA | DIO_DATA | DIO_RELEASE);
|
|
|
|
gfs2_glock_hold(gl);
|
|
gl->gl_req_bh = drop_bh;
|
|
|
|
ret = gfs2_lm_unlock(sdp, gl->gl_lock, gl->gl_state);
|
|
|
|
if (gfs2_assert_withdraw(sdp, !(ret & LM_OUT_ERROR)))
|
|
return;
|
|
|
|
if (!ret)
|
|
drop_bh(gl, ret);
|
|
else
|
|
gfs2_assert_warn(sdp, ret == LM_OUT_ASYNC);
|
|
}
|
|
|
|
/**
|
|
* do_cancels - cancel requests for locks stuck waiting on an expire flag
|
|
* @gh: the LM_FLAG_PRIORITY holder waiting to acquire the lock
|
|
*
|
|
* Don't cancel GL_NOCANCEL requests.
|
|
*/
|
|
|
|
static void do_cancels(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
while (gl->gl_req_gh != gh &&
|
|
!test_bit(HIF_HOLDER, &gh->gh_iflags) &&
|
|
!list_empty(&gh->gh_list)) {
|
|
if (gl->gl_req_bh && !(gl->gl_req_gh &&
|
|
(gl->gl_req_gh->gh_flags & GL_NOCANCEL))) {
|
|
spin_unlock(&gl->gl_spin);
|
|
gfs2_lm_cancel(gl->gl_sbd, gl->gl_lock);
|
|
msleep(100);
|
|
spin_lock(&gl->gl_spin);
|
|
} else {
|
|
spin_unlock(&gl->gl_spin);
|
|
msleep(100);
|
|
spin_lock(&gl->gl_spin);
|
|
}
|
|
}
|
|
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
/**
|
|
* glock_wait_internal - wait on a glock acquisition
|
|
* @gh: the glock holder
|
|
*
|
|
* Returns: 0 on success
|
|
*/
|
|
|
|
static int glock_wait_internal(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
if (test_bit(HIF_ABORTED, &gh->gh_iflags))
|
|
return -EIO;
|
|
|
|
if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) {
|
|
spin_lock(&gl->gl_spin);
|
|
if (gl->gl_req_gh != gh &&
|
|
!test_bit(HIF_HOLDER, &gh->gh_iflags) &&
|
|
!list_empty(&gh->gh_list)) {
|
|
list_del_init(&gh->gh_list);
|
|
gh->gh_error = GLR_TRYFAILED;
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
return gh->gh_error;
|
|
}
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
if (gh->gh_flags & LM_FLAG_PRIORITY)
|
|
do_cancels(gh);
|
|
|
|
wait_for_completion(&gh->gh_wait);
|
|
|
|
if (gh->gh_error)
|
|
return gh->gh_error;
|
|
|
|
gfs2_assert_withdraw(sdp, test_bit(HIF_HOLDER, &gh->gh_iflags));
|
|
gfs2_assert_withdraw(sdp, relaxed_state_ok(gl->gl_state, gh->gh_state,
|
|
gh->gh_flags));
|
|
|
|
if (test_bit(HIF_FIRST, &gh->gh_iflags)) {
|
|
gfs2_assert_warn(sdp, test_bit(GLF_LOCK, &gl->gl_flags));
|
|
|
|
if (glops->go_lock) {
|
|
gh->gh_error = glops->go_lock(gh);
|
|
if (gh->gh_error) {
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
}
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
gl->gl_req_gh = NULL;
|
|
gl->gl_req_bh = NULL;
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
return gh->gh_error;
|
|
}
|
|
|
|
static inline struct gfs2_holder *
|
|
find_holder_by_owner(struct list_head *head, struct task_struct *owner)
|
|
{
|
|
struct gfs2_holder *gh;
|
|
|
|
list_for_each_entry(gh, head, gh_list) {
|
|
if (gh->gh_owner == owner)
|
|
return gh;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* add_to_queue - Add a holder to the wait queue (but look for recursion)
|
|
* @gh: the holder structure to add
|
|
*
|
|
*/
|
|
|
|
static void add_to_queue(struct gfs2_holder *gh)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
struct gfs2_holder *existing;
|
|
|
|
BUG_ON(!gh->gh_owner);
|
|
|
|
existing = find_holder_by_owner(&gl->gl_holders, gh->gh_owner);
|
|
if (existing) {
|
|
print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
|
|
printk(KERN_INFO "pid : %d\n", existing->gh_owner->pid);
|
|
printk(KERN_INFO "lock type : %d lock state : %d\n",
|
|
existing->gh_gl->gl_name.ln_type, existing->gh_gl->gl_state);
|
|
print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
|
|
printk(KERN_INFO "pid : %d\n", gh->gh_owner->pid);
|
|
printk(KERN_INFO "lock type : %d lock state : %d\n",
|
|
gl->gl_name.ln_type, gl->gl_state);
|
|
BUG();
|
|
}
|
|
|
|
existing = find_holder_by_owner(&gl->gl_waiters3, gh->gh_owner);
|
|
if (existing) {
|
|
print_symbol(KERN_WARNING "original: %s\n", existing->gh_ip);
|
|
print_symbol(KERN_WARNING "new: %s\n", gh->gh_ip);
|
|
BUG();
|
|
}
|
|
|
|
if (gh->gh_flags & LM_FLAG_PRIORITY)
|
|
list_add(&gh->gh_list, &gl->gl_waiters3);
|
|
else
|
|
list_add_tail(&gh->gh_list, &gl->gl_waiters3);
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
int error = 0;
|
|
|
|
restart:
|
|
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) {
|
|
set_bit(HIF_ABORTED, &gh->gh_iflags);
|
|
return -EIO;
|
|
}
|
|
|
|
set_bit(HIF_PROMOTE, &gh->gh_iflags);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
add_to_queue(gh);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (!(gh->gh_flags & GL_ASYNC)) {
|
|
error = glock_wait_internal(gh);
|
|
if (error == GLR_CANCELED) {
|
|
msleep(100);
|
|
goto restart;
|
|
}
|
|
}
|
|
|
|
clear_bit(GLF_PREFETCH, &gl->gl_flags);
|
|
|
|
if (error == GLR_TRYFAILED && (gh->gh_flags & GL_DUMP))
|
|
dump_glock(gl);
|
|
|
|
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)
|
|
{
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
int ready = 0;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
if (test_bit(HIF_HOLDER, &gh->gh_iflags))
|
|
ready = 1;
|
|
else if (list_empty(&gh->gh_list)) {
|
|
if (gh->gh_error == GLR_CANCELED) {
|
|
spin_unlock(&gl->gl_spin);
|
|
msleep(100);
|
|
if (gfs2_glock_nq(gh))
|
|
return 1;
|
|
return 0;
|
|
} else
|
|
ready = 1;
|
|
}
|
|
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
return ready;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_wait - wait for a lock acquisition that ended in a GLR_ASYNC
|
|
* @gh: the holder structure
|
|
*
|
|
* Returns: 0, GLR_TRYFAILED, or errno on failure
|
|
*/
|
|
|
|
int gfs2_glock_wait(struct gfs2_holder *gh)
|
|
{
|
|
int error;
|
|
|
|
error = glock_wait_internal(gh);
|
|
if (error == GLR_CANCELED) {
|
|
msleep(100);
|
|
gh->gh_flags &= ~GL_ASYNC;
|
|
error = gfs2_glock_nq(gh);
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
if (gh->gh_flags & GL_NOCACHE)
|
|
handle_callback(gl, LM_ST_UNLOCKED);
|
|
|
|
gfs2_glmutex_lock(gl);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
list_del_init(&gh->gh_list);
|
|
|
|
if (list_empty(&gl->gl_holders)) {
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
if (glops->go_unlock)
|
|
glops->go_unlock(gh);
|
|
|
|
gl->gl_stamp = jiffies;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
}
|
|
|
|
clear_bit(GLF_LOCK, &gl->gl_flags);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_prefetch - Try to prefetch a glock
|
|
* @gl: the glock
|
|
* @state: the state to prefetch in
|
|
* @flags: flags passed to go_xmote_th()
|
|
*
|
|
*/
|
|
|
|
static void gfs2_glock_prefetch(struct gfs2_glock *gl, unsigned int state,
|
|
int flags)
|
|
{
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
if (test_bit(GLF_LOCK, &gl->gl_flags) || !list_empty(&gl->gl_holders) ||
|
|
!list_empty(&gl->gl_waiters1) || !list_empty(&gl->gl_waiters2) ||
|
|
!list_empty(&gl->gl_waiters3) ||
|
|
relaxed_state_ok(gl->gl_state, state, flags)) {
|
|
spin_unlock(&gl->gl_spin);
|
|
return;
|
|
}
|
|
|
|
set_bit(GLF_PREFETCH, &gl->gl_flags);
|
|
set_bit(GLF_LOCK, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
glops->go_xmote_th(gl, state, flags);
|
|
}
|
|
|
|
static void greedy_work(void *data)
|
|
{
|
|
struct greedy *gr = data;
|
|
struct gfs2_holder *gh = &gr->gr_gh;
|
|
struct gfs2_glock *gl = gh->gh_gl;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
|
|
clear_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
|
|
|
|
if (glops->go_greedy)
|
|
glops->go_greedy(gl);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
if (list_empty(&gl->gl_waiters2)) {
|
|
clear_bit(GLF_GREEDY, &gl->gl_flags);
|
|
spin_unlock(&gl->gl_spin);
|
|
gfs2_holder_uninit(gh);
|
|
kfree(gr);
|
|
} else {
|
|
gfs2_glock_hold(gl);
|
|
list_add_tail(&gh->gh_list, &gl->gl_waiters2);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
gfs2_glock_put(gl);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_be_greedy -
|
|
* @gl:
|
|
* @time:
|
|
*
|
|
* Returns: 0 if go_greedy will be called, 1 otherwise
|
|
*/
|
|
|
|
int gfs2_glock_be_greedy(struct gfs2_glock *gl, unsigned int time)
|
|
{
|
|
struct greedy *gr;
|
|
struct gfs2_holder *gh;
|
|
|
|
if (!time || gl->gl_sbd->sd_args.ar_localcaching ||
|
|
test_and_set_bit(GLF_GREEDY, &gl->gl_flags))
|
|
return 1;
|
|
|
|
gr = kmalloc(sizeof(struct greedy), GFP_KERNEL);
|
|
if (!gr) {
|
|
clear_bit(GLF_GREEDY, &gl->gl_flags);
|
|
return 1;
|
|
}
|
|
gh = &gr->gr_gh;
|
|
|
|
gfs2_holder_init(gl, 0, 0, gh);
|
|
set_bit(HIF_GREEDY, &gh->gh_iflags);
|
|
INIT_WORK(&gr->gr_work, greedy_work, gr);
|
|
|
|
set_bit(GLF_SKIP_WAITERS2, &gl->gl_flags);
|
|
schedule_delayed_work(&gr->gr_work, time);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* 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 aquisition
|
|
* @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, int 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;
|
|
if (gh_a->gh_state == LM_ST_SHARED && gh_b->gh_state == LM_ST_EXCLUSIVE)
|
|
return 1;
|
|
if (!(gh_a->gh_flags & GL_LOCAL_EXCL) && (gh_b->gh_flags & GL_LOCAL_EXCL))
|
|
return 1;
|
|
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
|
|
*
|
|
* 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
|
|
*
|
|
* Figure out how big an impact this function has. Either:
|
|
* 1) Replace this code with code that calls gfs2_glock_prefetch()
|
|
* 2) Forget async stuff and just call nq_m_sync()
|
|
* 3) Leave it like it is
|
|
*
|
|
* 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)
|
|
{
|
|
int *e;
|
|
unsigned int x;
|
|
int borked = 0, serious = 0;
|
|
int error = 0;
|
|
|
|
if (!num_gh)
|
|
return 0;
|
|
|
|
if (num_gh == 1) {
|
|
ghs->gh_flags &= ~(LM_FLAG_TRY | GL_ASYNC);
|
|
return gfs2_glock_nq(ghs);
|
|
}
|
|
|
|
e = kcalloc(num_gh, sizeof(struct gfs2_holder *), GFP_KERNEL);
|
|
if (!e)
|
|
return -ENOMEM;
|
|
|
|
for (x = 0; x < num_gh; x++) {
|
|
ghs[x].gh_flags |= LM_FLAG_TRY | GL_ASYNC;
|
|
error = gfs2_glock_nq(&ghs[x]);
|
|
if (error) {
|
|
borked = 1;
|
|
serious = error;
|
|
num_gh = x;
|
|
break;
|
|
}
|
|
}
|
|
|
|
for (x = 0; x < num_gh; x++) {
|
|
error = e[x] = glock_wait_internal(&ghs[x]);
|
|
if (error) {
|
|
borked = 1;
|
|
if (error != GLR_TRYFAILED && error != GLR_CANCELED)
|
|
serious = error;
|
|
}
|
|
}
|
|
|
|
if (!borked) {
|
|
kfree(e);
|
|
return 0;
|
|
}
|
|
|
|
for (x = 0; x < num_gh; x++)
|
|
if (!e[x])
|
|
gfs2_glock_dq(&ghs[x]);
|
|
|
|
if (serious)
|
|
error = serious;
|
|
else {
|
|
for (x = 0; x < num_gh; x++)
|
|
gfs2_holder_reinit(ghs[x].gh_state, ghs[x].gh_flags,
|
|
&ghs[x]);
|
|
error = nq_m_sync(num_gh, ghs, (struct gfs2_holder **)e);
|
|
}
|
|
|
|
kfree(e);
|
|
|
|
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)
|
|
{
|
|
unsigned int x;
|
|
|
|
for (x = 0; x < num_gh; x++)
|
|
gfs2_glock_dq(&ghs[x]);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_dq_uninit_m - release multiple glocks
|
|
* @num_gh: the number of structures
|
|
* @ghs: an array of struct gfs2_holder structures
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs)
|
|
{
|
|
unsigned int x;
|
|
|
|
for (x = 0; x < num_gh; x++)
|
|
gfs2_glock_dq_uninit(&ghs[x]);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_prefetch_num - prefetch 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 aquisition
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
void gfs2_glock_prefetch_num(struct gfs2_sbd *sdp, u64 number,
|
|
const struct gfs2_glock_operations *glops,
|
|
unsigned int state, int flags)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
int error;
|
|
|
|
if (atomic_read(&sdp->sd_reclaim_count) <
|
|
gfs2_tune_get(sdp, gt_reclaim_limit)) {
|
|
error = gfs2_glock_get(sdp, number, glops, CREATE, &gl);
|
|
if (!error) {
|
|
gfs2_glock_prefetch(gl, state, flags);
|
|
gfs2_glock_put(gl);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_lvb_hold - attach a LVB from a glock
|
|
* @gl: The glock in question
|
|
*
|
|
*/
|
|
|
|
int gfs2_lvb_hold(struct gfs2_glock *gl)
|
|
{
|
|
int error;
|
|
|
|
gfs2_glmutex_lock(gl);
|
|
|
|
if (!atomic_read(&gl->gl_lvb_count)) {
|
|
error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb);
|
|
if (error) {
|
|
gfs2_glmutex_unlock(gl);
|
|
return error;
|
|
}
|
|
gfs2_glock_hold(gl);
|
|
}
|
|
atomic_inc(&gl->gl_lvb_count);
|
|
|
|
gfs2_glmutex_unlock(gl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_lvb_unhold - detach a LVB from a glock
|
|
* @gl: The glock in question
|
|
*
|
|
*/
|
|
|
|
void gfs2_lvb_unhold(struct gfs2_glock *gl)
|
|
{
|
|
gfs2_glock_hold(gl);
|
|
gfs2_glmutex_lock(gl);
|
|
|
|
gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0);
|
|
if (atomic_dec_and_test(&gl->gl_lvb_count)) {
|
|
gfs2_lm_unhold_lvb(gl->gl_sbd, gl->gl_lock, gl->gl_lvb);
|
|
gl->gl_lvb = NULL;
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
gfs2_glmutex_unlock(gl);
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name,
|
|
unsigned int state)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
|
|
gl = gfs2_glock_find(sdp, name);
|
|
if (!gl)
|
|
return;
|
|
|
|
if (gl->gl_ops->go_callback)
|
|
gl->gl_ops->go_callback(gl, state);
|
|
handle_callback(gl, state);
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
run_queue(gl);
|
|
spin_unlock(&gl->gl_spin);
|
|
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_cb - Callback used by locking module
|
|
* @sdp: Pointer to the superblock
|
|
* @type: Type of callback
|
|
* @data: Type dependent data pointer
|
|
*
|
|
* Called by the locking module when it wants to tell us something.
|
|
* Either we need to drop a lock, one of our ASYNC requests completed, or
|
|
* a journal from another client needs to be recovered.
|
|
*/
|
|
|
|
void gfs2_glock_cb(void *cb_data, unsigned int type, void *data)
|
|
{
|
|
struct gfs2_sbd *sdp = cb_data;
|
|
|
|
switch (type) {
|
|
case LM_CB_NEED_E:
|
|
blocking_cb(sdp, data, LM_ST_UNLOCKED);
|
|
return;
|
|
|
|
case LM_CB_NEED_D:
|
|
blocking_cb(sdp, data, LM_ST_DEFERRED);
|
|
return;
|
|
|
|
case LM_CB_NEED_S:
|
|
blocking_cb(sdp, data, LM_ST_SHARED);
|
|
return;
|
|
|
|
case LM_CB_ASYNC: {
|
|
struct lm_async_cb *async = data;
|
|
struct gfs2_glock *gl;
|
|
|
|
gl = gfs2_glock_find(sdp, &async->lc_name);
|
|
if (gfs2_assert_warn(sdp, gl))
|
|
return;
|
|
if (!gfs2_assert_warn(sdp, gl->gl_req_bh))
|
|
gl->gl_req_bh(gl, async->lc_ret);
|
|
gfs2_glock_put(gl);
|
|
return;
|
|
}
|
|
|
|
case LM_CB_NEED_RECOVERY:
|
|
gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data);
|
|
if (sdp->sd_recoverd_process)
|
|
wake_up_process(sdp->sd_recoverd_process);
|
|
return;
|
|
|
|
case LM_CB_DROPLOCKS:
|
|
gfs2_gl_hash_clear(sdp, NO_WAIT);
|
|
gfs2_quota_scan(sdp);
|
|
return;
|
|
|
|
default:
|
|
gfs2_assert_warn(sdp, 0);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* demote_ok - Check to see if it's ok to unlock a glock
|
|
* @gl: the glock
|
|
*
|
|
* Returns: 1 if it's ok
|
|
*/
|
|
|
|
static int demote_ok(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
const struct gfs2_glock_operations *glops = gl->gl_ops;
|
|
int demote = 1;
|
|
|
|
if (test_bit(GLF_STICKY, &gl->gl_flags))
|
|
demote = 0;
|
|
else if (test_bit(GLF_PREFETCH, &gl->gl_flags))
|
|
demote = time_after_eq(jiffies, gl->gl_stamp +
|
|
gfs2_tune_get(sdp, gt_prefetch_secs) * HZ);
|
|
else if (glops->go_demote_ok)
|
|
demote = glops->go_demote_ok(gl);
|
|
|
|
return demote;
|
|
}
|
|
|
|
/**
|
|
* gfs2_glock_schedule_for_reclaim - Add a glock to the reclaim list
|
|
* @gl: the glock
|
|
*
|
|
*/
|
|
|
|
void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
|
|
spin_lock(&sdp->sd_reclaim_lock);
|
|
if (list_empty(&gl->gl_reclaim)) {
|
|
gfs2_glock_hold(gl);
|
|
list_add(&gl->gl_reclaim, &sdp->sd_reclaim_list);
|
|
atomic_inc(&sdp->sd_reclaim_count);
|
|
}
|
|
spin_unlock(&sdp->sd_reclaim_lock);
|
|
|
|
wake_up(&sdp->sd_reclaim_wq);
|
|
}
|
|
|
|
/**
|
|
* gfs2_reclaim_glock - process the next glock on the filesystem's reclaim list
|
|
* @sdp: the filesystem
|
|
*
|
|
* Called from gfs2_glockd() glock reclaim daemon, or when promoting a
|
|
* different glock and we notice that there are a lot of glocks in the
|
|
* reclaim list.
|
|
*
|
|
*/
|
|
|
|
void gfs2_reclaim_glock(struct gfs2_sbd *sdp)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
|
|
spin_lock(&sdp->sd_reclaim_lock);
|
|
if (list_empty(&sdp->sd_reclaim_list)) {
|
|
spin_unlock(&sdp->sd_reclaim_lock);
|
|
return;
|
|
}
|
|
gl = list_entry(sdp->sd_reclaim_list.next,
|
|
struct gfs2_glock, gl_reclaim);
|
|
list_del_init(&gl->gl_reclaim);
|
|
spin_unlock(&sdp->sd_reclaim_lock);
|
|
|
|
atomic_dec(&sdp->sd_reclaim_count);
|
|
atomic_inc(&sdp->sd_reclaimed);
|
|
|
|
if (gfs2_glmutex_trylock(gl)) {
|
|
if (queue_empty(gl, &gl->gl_holders) &&
|
|
gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
|
|
handle_callback(gl, LM_ST_UNLOCKED);
|
|
gfs2_glmutex_unlock(gl);
|
|
}
|
|
|
|
gfs2_glock_put(gl);
|
|
}
|
|
|
|
/**
|
|
* examine_bucket - Call a function for glock in a hash bucket
|
|
* @examiner: the function
|
|
* @sdp: the filesystem
|
|
* @bucket: the bucket
|
|
*
|
|
* Returns: 1 if the bucket has entries
|
|
*/
|
|
|
|
static int examine_bucket(glock_examiner examiner, struct gfs2_sbd *sdp,
|
|
unsigned int hash)
|
|
{
|
|
struct gfs2_glock *gl, *prev = NULL;
|
|
int has_entries = 0;
|
|
struct hlist_head *head = &gl_hash_table[hash].hb_list;
|
|
|
|
read_lock(gl_lock_addr(hash));
|
|
/* Can't use hlist_for_each_entry - don't want prefetch here */
|
|
if (hlist_empty(head))
|
|
goto out;
|
|
gl = list_entry(head->first, struct gfs2_glock, gl_list);
|
|
while(1) {
|
|
if (gl->gl_sbd == sdp) {
|
|
gfs2_glock_hold(gl);
|
|
read_unlock(gl_lock_addr(hash));
|
|
if (prev)
|
|
gfs2_glock_put(prev);
|
|
prev = gl;
|
|
examiner(gl);
|
|
has_entries = 1;
|
|
read_lock(gl_lock_addr(hash));
|
|
}
|
|
if (gl->gl_list.next == NULL)
|
|
break;
|
|
gl = list_entry(gl->gl_list.next, struct gfs2_glock, gl_list);
|
|
}
|
|
out:
|
|
read_unlock(gl_lock_addr(hash));
|
|
if (prev)
|
|
gfs2_glock_put(prev);
|
|
return has_entries;
|
|
}
|
|
|
|
/**
|
|
* scan_glock - look at a glock and see if we can reclaim it
|
|
* @gl: the glock to look at
|
|
*
|
|
*/
|
|
|
|
static void scan_glock(struct gfs2_glock *gl)
|
|
{
|
|
if (gl->gl_ops == &gfs2_inode_glops)
|
|
return;
|
|
|
|
if (gfs2_glmutex_trylock(gl)) {
|
|
if (queue_empty(gl, &gl->gl_holders) &&
|
|
gl->gl_state != LM_ST_UNLOCKED && demote_ok(gl))
|
|
goto out_schedule;
|
|
gfs2_glmutex_unlock(gl);
|
|
}
|
|
return;
|
|
|
|
out_schedule:
|
|
gfs2_glmutex_unlock(gl);
|
|
gfs2_glock_schedule_for_reclaim(gl);
|
|
}
|
|
|
|
/**
|
|
* gfs2_scand_internal - Look for glocks and inodes to toss from memory
|
|
* @sdp: the filesystem
|
|
*
|
|
*/
|
|
|
|
void gfs2_scand_internal(struct gfs2_sbd *sdp)
|
|
{
|
|
unsigned int x;
|
|
|
|
for (x = 0; x < GFS2_GL_HASH_SIZE; x++)
|
|
examine_bucket(scan_glock, sdp, x);
|
|
}
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
struct gfs2_sbd *sdp = gl->gl_sbd;
|
|
int released;
|
|
|
|
spin_lock(&sdp->sd_reclaim_lock);
|
|
if (!list_empty(&gl->gl_reclaim)) {
|
|
list_del_init(&gl->gl_reclaim);
|
|
atomic_dec(&sdp->sd_reclaim_count);
|
|
spin_unlock(&sdp->sd_reclaim_lock);
|
|
released = gfs2_glock_put(gl);
|
|
gfs2_assert(sdp, !released);
|
|
} else {
|
|
spin_unlock(&sdp->sd_reclaim_lock);
|
|
}
|
|
|
|
if (gfs2_glmutex_trylock(gl)) {
|
|
if (queue_empty(gl, &gl->gl_holders) &&
|
|
gl->gl_state != LM_ST_UNLOCKED)
|
|
handle_callback(gl, LM_ST_UNLOCKED);
|
|
gfs2_glmutex_unlock(gl);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_gl_hash_clear - Empty out the glock hash table
|
|
* @sdp: the filesystem
|
|
* @wait: wait until it's all gone
|
|
*
|
|
* Called when unmounting the filesystem, or when inter-node lock manager
|
|
* requests DROPLOCKS because it is running out of capacity.
|
|
*/
|
|
|
|
void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
|
|
{
|
|
unsigned long t;
|
|
unsigned int x;
|
|
int cont;
|
|
|
|
t = jiffies;
|
|
|
|
for (;;) {
|
|
cont = 0;
|
|
for (x = 0; x < GFS2_GL_HASH_SIZE; x++) {
|
|
if (examine_bucket(clear_glock, sdp, x))
|
|
cont = 1;
|
|
}
|
|
|
|
if (!wait || !cont)
|
|
break;
|
|
|
|
if (time_after_eq(jiffies,
|
|
t + gfs2_tune_get(sdp, gt_stall_secs) * HZ)) {
|
|
fs_warn(sdp, "Unmount seems to be stalled. "
|
|
"Dumping lock state...\n");
|
|
gfs2_dump_lockstate(sdp);
|
|
t = jiffies;
|
|
}
|
|
|
|
invalidate_inodes(sdp->sd_vfs);
|
|
msleep(10);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Diagnostic routines to help debug distributed deadlock
|
|
*/
|
|
|
|
/**
|
|
* dump_holder - print information about a glock holder
|
|
* @str: a string naming the type of holder
|
|
* @gh: the glock holder
|
|
*
|
|
* Returns: 0 on success, -ENOBUFS when we run out of space
|
|
*/
|
|
|
|
static int dump_holder(char *str, struct gfs2_holder *gh)
|
|
{
|
|
unsigned int x;
|
|
int error = -ENOBUFS;
|
|
|
|
printk(KERN_INFO " %s\n", str);
|
|
printk(KERN_INFO " owner = %ld\n",
|
|
(gh->gh_owner) ? (long)gh->gh_owner->pid : -1);
|
|
printk(KERN_INFO " gh_state = %u\n", gh->gh_state);
|
|
printk(KERN_INFO " gh_flags =");
|
|
for (x = 0; x < 32; x++)
|
|
if (gh->gh_flags & (1 << x))
|
|
printk(" %u", x);
|
|
printk(" \n");
|
|
printk(KERN_INFO " error = %d\n", gh->gh_error);
|
|
printk(KERN_INFO " gh_iflags =");
|
|
for (x = 0; x < 32; x++)
|
|
if (test_bit(x, &gh->gh_iflags))
|
|
printk(" %u", x);
|
|
printk(" \n");
|
|
print_symbol(KERN_INFO " initialized at: %s\n", gh->gh_ip);
|
|
|
|
error = 0;
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* dump_inode - print information about an inode
|
|
* @ip: the inode
|
|
*
|
|
* Returns: 0 on success, -ENOBUFS when we run out of space
|
|
*/
|
|
|
|
static int dump_inode(struct gfs2_inode *ip)
|
|
{
|
|
unsigned int x;
|
|
int error = -ENOBUFS;
|
|
|
|
printk(KERN_INFO " Inode:\n");
|
|
printk(KERN_INFO " num = %llu %llu\n",
|
|
(unsigned long long)ip->i_num.no_formal_ino,
|
|
(unsigned long long)ip->i_num.no_addr);
|
|
printk(KERN_INFO " type = %u\n", IF2DT(ip->i_di.di_mode));
|
|
printk(KERN_INFO " i_flags =");
|
|
for (x = 0; x < 32; x++)
|
|
if (test_bit(x, &ip->i_flags))
|
|
printk(" %u", x);
|
|
printk(" \n");
|
|
|
|
error = 0;
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* dump_glock - print information about a glock
|
|
* @gl: the glock
|
|
* @count: where we are in the buffer
|
|
*
|
|
* Returns: 0 on success, -ENOBUFS when we run out of space
|
|
*/
|
|
|
|
static int dump_glock(struct gfs2_glock *gl)
|
|
{
|
|
struct gfs2_holder *gh;
|
|
unsigned int x;
|
|
int error = -ENOBUFS;
|
|
|
|
spin_lock(&gl->gl_spin);
|
|
|
|
printk(KERN_INFO "Glock 0x%p (%u, %llu)\n", gl, gl->gl_name.ln_type,
|
|
(unsigned long long)gl->gl_name.ln_number);
|
|
printk(KERN_INFO " gl_flags =");
|
|
for (x = 0; x < 32; x++) {
|
|
if (test_bit(x, &gl->gl_flags))
|
|
printk(" %u", x);
|
|
}
|
|
printk(" \n");
|
|
printk(KERN_INFO " gl_ref = %d\n", atomic_read(&gl->gl_ref));
|
|
printk(KERN_INFO " gl_state = %u\n", gl->gl_state);
|
|
printk(KERN_INFO " gl_owner = %s\n", gl->gl_owner->comm);
|
|
print_symbol(KERN_INFO " gl_ip = %s\n", gl->gl_ip);
|
|
printk(KERN_INFO " req_gh = %s\n", (gl->gl_req_gh) ? "yes" : "no");
|
|
printk(KERN_INFO " req_bh = %s\n", (gl->gl_req_bh) ? "yes" : "no");
|
|
printk(KERN_INFO " lvb_count = %d\n", atomic_read(&gl->gl_lvb_count));
|
|
printk(KERN_INFO " object = %s\n", (gl->gl_object) ? "yes" : "no");
|
|
printk(KERN_INFO " le = %s\n",
|
|
(list_empty(&gl->gl_le.le_list)) ? "no" : "yes");
|
|
printk(KERN_INFO " reclaim = %s\n",
|
|
(list_empty(&gl->gl_reclaim)) ? "no" : "yes");
|
|
if (gl->gl_aspace)
|
|
printk(KERN_INFO " aspace = 0x%p nrpages = %lu\n", gl->gl_aspace,
|
|
gl->gl_aspace->i_mapping->nrpages);
|
|
else
|
|
printk(KERN_INFO " aspace = no\n");
|
|
printk(KERN_INFO " ail = %d\n", atomic_read(&gl->gl_ail_count));
|
|
if (gl->gl_req_gh) {
|
|
error = dump_holder("Request", gl->gl_req_gh);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
list_for_each_entry(gh, &gl->gl_holders, gh_list) {
|
|
error = dump_holder("Holder", gh);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
list_for_each_entry(gh, &gl->gl_waiters1, gh_list) {
|
|
error = dump_holder("Waiter1", gh);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
list_for_each_entry(gh, &gl->gl_waiters2, gh_list) {
|
|
error = dump_holder("Waiter2", gh);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
list_for_each_entry(gh, &gl->gl_waiters3, gh_list) {
|
|
error = dump_holder("Waiter3", gh);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) {
|
|
if (!test_bit(GLF_LOCK, &gl->gl_flags) &&
|
|
list_empty(&gl->gl_holders)) {
|
|
error = dump_inode(gl->gl_object);
|
|
if (error)
|
|
goto out;
|
|
} else {
|
|
error = -ENOBUFS;
|
|
printk(KERN_INFO " Inode: busy\n");
|
|
}
|
|
}
|
|
|
|
error = 0;
|
|
|
|
out:
|
|
spin_unlock(&gl->gl_spin);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_dump_lockstate - print out the current lockstate
|
|
* @sdp: the filesystem
|
|
* @ub: the buffer to copy the information into
|
|
*
|
|
* If @ub is NULL, dump the lockstate to the console.
|
|
*
|
|
*/
|
|
|
|
static int gfs2_dump_lockstate(struct gfs2_sbd *sdp)
|
|
{
|
|
struct gfs2_glock *gl;
|
|
struct hlist_node *h;
|
|
unsigned int x;
|
|
int error = 0;
|
|
|
|
for (x = 0; x < GFS2_GL_HASH_SIZE; x++) {
|
|
|
|
read_lock(gl_lock_addr(x));
|
|
|
|
hlist_for_each_entry(gl, h, &gl_hash_table[x].hb_list, gl_list) {
|
|
if (gl->gl_sbd != sdp)
|
|
continue;
|
|
|
|
error = dump_glock(gl);
|
|
if (error)
|
|
break;
|
|
}
|
|
|
|
read_unlock(gl_lock_addr(x));
|
|
|
|
if (error)
|
|
break;
|
|
}
|
|
|
|
|
|
return error;
|
|
}
|
|
|
|
int __init gfs2_glock_init(void)
|
|
{
|
|
unsigned i;
|
|
for(i = 0; i < GFS2_GL_HASH_SIZE; i++) {
|
|
INIT_HLIST_HEAD(&gl_hash_table[i].hb_list);
|
|
}
|
|
#ifdef GL_HASH_LOCK_SZ
|
|
for(i = 0; i < GL_HASH_LOCK_SZ; i++) {
|
|
rwlock_init(&gl_hash_locks[i]);
|
|
}
|
|
#endif
|
|
return 0;
|
|
}
|
|
|