fs/gfs2/glock.h - kernel/msm-5.4 - Gitiles

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
  * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
  */

 #ifndef __GLOCK_DOT_H__
 #define __GLOCK_DOT_H__

 #include <linux/sched.h>
 #include <linux/parser.h>
 #include "incore.h"
 #include "util.h"

 /* Options for hostdata parser */

 enum {
 	Opt_jid,
 	Opt_id,
 	Opt_first,
 	Opt_nodir,
 	Opt_err,
 };

 /*
  * lm_lockname types
  */

 #define LM_TYPE_RESERVED	0x00
 #define LM_TYPE_NONDISK		0x01
 #define LM_TYPE_INODE		0x02
 #define LM_TYPE_RGRP		0x03
 #define LM_TYPE_META		0x04
 #define LM_TYPE_IOPEN		0x05
 #define LM_TYPE_FLOCK		0x06
 #define LM_TYPE_PLOCK		0x07
 #define LM_TYPE_QUOTA		0x08
 #define LM_TYPE_JOURNAL		0x09

 /*
  * lm_lock() states
  *
  * SHARED is compatible with SHARED, not with DEFERRED or EX.
  * DEFERRED is compatible with DEFERRED, not with SHARED or EX.
  */

 #define LM_ST_UNLOCKED		0
 #define LM_ST_EXCLUSIVE		1
 #define LM_ST_DEFERRED		2
 #define LM_ST_SHARED		3

 /*
  * lm_lock() flags
  *
  * LM_FLAG_TRY
  * Don't wait to acquire the lock if it can't be granted immediately.
  *
  * LM_FLAG_TRY_1CB
  * Send one blocking callback if TRY is set and the lock is not granted.
  *
  * LM_FLAG_NOEXP
  * GFS sets this flag on lock requests it makes while doing journal recovery.
  * These special requests should not be blocked due to the recovery like
  * ordinary locks would be.
  *
  * LM_FLAG_ANY
  * A SHARED request may also be granted in DEFERRED, or a DEFERRED request may
  * also be granted in SHARED.  The preferred state is whichever is compatible
  * with other granted locks, or the specified state if no other locks exist.
  *
  * LM_FLAG_PRIORITY
  * Override fairness considerations.  Suppose a lock is held in a shared state
  * and there is a pending request for the deferred state.  A shared lock
  * request with the priority flag would be allowed to bypass the deferred
  * request and directly join the other shared lock.  A shared lock request
  * without the priority flag might be forced to wait until the deferred
  * requested had acquired and released the lock.
  */

 #define LM_FLAG_TRY		0x0001
 #define LM_FLAG_TRY_1CB		0x0002
 #define LM_FLAG_NOEXP		0x0004
 #define LM_FLAG_ANY		0x0008
 #define LM_FLAG_PRIORITY	0x0010
 #define GL_ASYNC		0x0040
 #define GL_EXACT		0x0080
 #define GL_SKIP			0x0100
 #define GL_NOCACHE		0x0400

 /*
  * lm_async_cb return flags
  *
  * LM_OUT_ST_MASK
  * Masks the lower two bits of lock state in the returned value.
  *
  * LM_OUT_CANCELED
  * The lock request was canceled.
  *
  */

 #define LM_OUT_ST_MASK		0x00000003
 #define LM_OUT_CANCELED		0x00000008
 #define LM_OUT_ERROR		0x00000004

 /*
  * lm_recovery_done() messages
  */

 #define LM_RD_GAVEUP		308
 #define LM_RD_SUCCESS		309

 #define GLR_TRYFAILED		13

 #define GL_GLOCK_MAX_HOLD        (long)(HZ / 5)
 #define GL_GLOCK_DFT_HOLD        (long)(HZ / 5)
 #define GL_GLOCK_MIN_HOLD        (long)(10)
 #define GL_GLOCK_HOLD_INCR       (long)(HZ / 20)
 #define GL_GLOCK_HOLD_DECR       (long)(HZ / 40)

 struct lm_lockops {
 	const char *lm_proto_name;
 	int (*lm_mount) (struct gfs2_sbd *sdp, const char *table);
 	void (*lm_first_done) (struct gfs2_sbd *sdp);
 	void (*lm_recovery_result) (struct gfs2_sbd *sdp, unsigned int jid,
 				    unsigned int result);
 	void (*lm_unmount) (struct gfs2_sbd *sdp);
 	void (*lm_withdraw) (struct gfs2_sbd *sdp);
 	void (*lm_put_lock) (struct gfs2_glock *gl);
 	int (*lm_lock) (struct gfs2_glock *gl, unsigned int req_state,
 			unsigned int flags);
 	void (*lm_cancel) (struct gfs2_glock *gl);
 	const match_table_t *lm_tokens;
 };

 extern struct workqueue_struct *gfs2_delete_workqueue;
 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl)
 {
 	struct gfs2_holder *gh;
 	struct pid *pid;

 	/* Look in glock's list of holders for one with current task as owner */
 	spin_lock(&gl->gl_lockref.lock);
 	pid = task_pid(current);
 	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
 		if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
 			break;
 		if (gh->gh_owner_pid == pid)
 			goto out;
 	}
 	gh = NULL;
 out:
 	spin_unlock(&gl->gl_lockref.lock);

 	return gh;
 }

 static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
 {
 	return gl->gl_state == LM_ST_EXCLUSIVE;
 }

 static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
 {
 	return gl->gl_state == LM_ST_DEFERRED;
 }

 static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
 {
 	return gl->gl_state == LM_ST_SHARED;
 }

 static inline struct address_space *gfs2_glock2aspace(struct gfs2_glock *gl)
 {
 	if (gl->gl_ops->go_flags & GLOF_ASPACE)
 		return (struct address_space *)(gl + 1);
 	return NULL;
 }

 extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
 			  const struct gfs2_glock_operations *glops,
 			  int create, struct gfs2_glock **glp);
 extern void gfs2_glock_hold(struct gfs2_glock *gl);
 extern void gfs2_glock_put(struct gfs2_glock *gl);
 extern void gfs2_glock_queue_put(struct gfs2_glock *gl);
 extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
 			     u16 flags, struct gfs2_holder *gh);
 extern void gfs2_holder_reinit(unsigned int state, u16 flags,
 			       struct gfs2_holder *gh);
 extern void gfs2_holder_uninit(struct gfs2_holder *gh);
 extern int gfs2_glock_nq(struct gfs2_holder *gh);
 extern int gfs2_glock_poll(struct gfs2_holder *gh);
 extern int gfs2_glock_wait(struct gfs2_holder *gh);
 extern void gfs2_glock_dq(struct gfs2_holder *gh);
 extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
 extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
 extern 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);
 extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
 extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
 extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl);
 #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { gfs2_dump_glock(NULL, gl); BUG(); } } while(0)
 extern __printf(2, 3)
 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);

 /**
  * gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
  * @gl: the glock
  * @state: the state we're requesting
  * @flags: the modifier flags
  * @gh: the holder structure
  *
  * Returns: 0, GLR_*, or errno
  */

 static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
 				     unsigned int state, u16 flags,
 				     struct gfs2_holder *gh)
 {
 	int error;

 	gfs2_holder_init(gl, state, flags, gh);

 	error = gfs2_glock_nq(gh);
 	if (error)
 		gfs2_holder_uninit(gh);

 	return error;
 }

 extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
 extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
 extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
 extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip);
 extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
 extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
 extern void gfs2_glock_free(struct gfs2_glock *gl);

 extern int __init gfs2_glock_init(void);
 extern void gfs2_glock_exit(void);

 extern void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
 extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
 extern void gfs2_register_debugfs(void);
 extern void gfs2_unregister_debugfs(void);

 extern const struct lm_lockops gfs2_dlm_ops;

 static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
 {
 	gh->gh_gl = NULL;
 }

 static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
 {
 	return gh->gh_gl;
 }

 /**
  * glock_set_object - set the gl_object field of a glock
  * @gl: the glock
  * @object: the object
  */
 static inline void glock_set_object(struct gfs2_glock *gl, void *object)
 {
 	spin_lock(&gl->gl_lockref.lock);
 	if (gfs2_assert_warn(gl->gl_name.ln_sbd, gl->gl_object == NULL))
 		gfs2_dump_glock(NULL, gl);
 	gl->gl_object = object;
 	spin_unlock(&gl->gl_lockref.lock);
 }

 /**
  * glock_clear_object - clear the gl_object field of a glock
  * @gl: the glock
  * @object: the object
  *
  * I'd love to similarly add this:
  *	else if (gfs2_assert_warn(gl->gl_sbd, gl->gl_object == object))
  *		gfs2_dump_glock(NULL, gl);
  * Unfortunately, that's not possible because as soon as gfs2_delete_inode
  * frees the block in the rgrp, another process can reassign it for an I_NEW
  * inode in gfs2_create_inode because that calls new_inode, not gfs2_iget.
  * That means gfs2_delete_inode may subsequently try to call this function
  * for a glock that's already pointing to a brand new inode. If we clear the
  * new inode's gl_object, we'll introduce metadata corruption. Function
  * gfs2_delete_inode calls clear_inode which calls gfs2_clear_inode which also
  * tries to clear gl_object, so it's more than just gfs2_delete_inode.
  *
  */
 static inline void glock_clear_object(struct gfs2_glock *gl, void *object)
 {
 	spin_lock(&gl->gl_lockref.lock);
 	if (gl->gl_object == object)
 		gl->gl_object = NULL;
 	spin_unlock(&gl->gl_lockref.lock);
 }

 #endif /* __GLOCK_DOT_H__ */
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
	*/

	#ifndef __GLOCK_DOT_H__
	#define __GLOCK_DOT_H__

	#include <linux/sched.h>
	#include <linux/parser.h>
	#include "incore.h"
	#include "util.h"

	/* Options for hostdata parser */

	enum {
	Opt_jid,
	Opt_id,
	Opt_first,
	Opt_nodir,
	Opt_err,
	};

	/*
	* lm_lockname types
	*/

	#define LM_TYPE_RESERVED 0x00
	#define LM_TYPE_NONDISK 0x01
	#define LM_TYPE_INODE 0x02
	#define LM_TYPE_RGRP 0x03
	#define LM_TYPE_META 0x04
	#define LM_TYPE_IOPEN 0x05
	#define LM_TYPE_FLOCK 0x06
	#define LM_TYPE_PLOCK 0x07
	#define LM_TYPE_QUOTA 0x08
	#define LM_TYPE_JOURNAL 0x09

	/*
	* lm_lock() states
	*
	* SHARED is compatible with SHARED, not with DEFERRED or EX.
	* DEFERRED is compatible with DEFERRED, not with SHARED or EX.
	*/

	#define LM_ST_UNLOCKED 0
	#define LM_ST_EXCLUSIVE 1
	#define LM_ST_DEFERRED 2
	#define LM_ST_SHARED 3

	/*
	* lm_lock() flags
	*
	* LM_FLAG_TRY
	* Don't wait to acquire the lock if it can't be granted immediately.
	*
	* LM_FLAG_TRY_1CB
	* Send one blocking callback if TRY is set and the lock is not granted.
	*
	* LM_FLAG_NOEXP
	* GFS sets this flag on lock requests it makes while doing journal recovery.
	* These special requests should not be blocked due to the recovery like
	* ordinary locks would be.
	*
	* LM_FLAG_ANY
	* A SHARED request may also be granted in DEFERRED, or a DEFERRED request may
	* also be granted in SHARED. The preferred state is whichever is compatible
	* with other granted locks, or the specified state if no other locks exist.
	*
	* LM_FLAG_PRIORITY
	* Override fairness considerations. Suppose a lock is held in a shared state
	* and there is a pending request for the deferred state. A shared lock
	* request with the priority flag would be allowed to bypass the deferred
	* request and directly join the other shared lock. A shared lock request
	* without the priority flag might be forced to wait until the deferred
	* requested had acquired and released the lock.
	*/

	#define LM_FLAG_TRY 0x0001
	#define LM_FLAG_TRY_1CB 0x0002
	#define LM_FLAG_NOEXP 0x0004
	#define LM_FLAG_ANY 0x0008
	#define LM_FLAG_PRIORITY 0x0010
	#define GL_ASYNC 0x0040
	#define GL_EXACT 0x0080
	#define GL_SKIP 0x0100
	#define GL_NOCACHE 0x0400

	/*
	* lm_async_cb return flags
	*
	* LM_OUT_ST_MASK
	* Masks the lower two bits of lock state in the returned value.
	*
	* LM_OUT_CANCELED
	* The lock request was canceled.
	*
	*/

	#define LM_OUT_ST_MASK 0x00000003
	#define LM_OUT_CANCELED 0x00000008
	#define LM_OUT_ERROR 0x00000004

	/*
	* lm_recovery_done() messages
	*/

	#define LM_RD_GAVEUP 308
	#define LM_RD_SUCCESS 309

	#define GLR_TRYFAILED 13

	#define GL_GLOCK_MAX_HOLD (long)(HZ / 5)
	#define GL_GLOCK_DFT_HOLD (long)(HZ / 5)
	#define GL_GLOCK_MIN_HOLD (long)(10)
	#define GL_GLOCK_HOLD_INCR (long)(HZ / 20)
	#define GL_GLOCK_HOLD_DECR (long)(HZ / 40)

	struct lm_lockops {
	const char *lm_proto_name;
	int (lm_mount) (struct gfs2_sbd sdp, const char *table);
	void (lm_first_done) (struct gfs2_sbd sdp);
	void (lm_recovery_result) (struct gfs2_sbd sdp, unsigned int jid,
	unsigned int result);
	void (lm_unmount) (struct gfs2_sbd sdp);
	void (lm_withdraw) (struct gfs2_sbd sdp);
	void (lm_put_lock) (struct gfs2_glock gl);
	int (lm_lock) (struct gfs2_glock gl, unsigned int req_state,
	unsigned int flags);
	void (lm_cancel) (struct gfs2_glock gl);
	const match_table_t *lm_tokens;
	};

	extern struct workqueue_struct *gfs2_delete_workqueue;
	static inline struct gfs2_holder gfs2_glock_is_locked_by_me(struct gfs2_glock gl)
	{
	struct gfs2_holder *gh;
	struct pid *pid;

	/* Look in glock's list of holders for one with current task as owner */
	spin_lock(&gl->gl_lockref.lock);
	pid = task_pid(current);
	list_for_each_entry(gh, &gl->gl_holders, gh_list) {
	if (!test_bit(HIF_HOLDER, &gh->gh_iflags))
	break;
	if (gh->gh_owner_pid == pid)
	goto out;
	}
	gh = NULL;
	out:
	spin_unlock(&gl->gl_lockref.lock);

	return gh;
	}

	static inline int gfs2_glock_is_held_excl(struct gfs2_glock *gl)
	{
	return gl->gl_state == LM_ST_EXCLUSIVE;
	}

	static inline int gfs2_glock_is_held_dfrd(struct gfs2_glock *gl)
	{
	return gl->gl_state == LM_ST_DEFERRED;
	}

	static inline int gfs2_glock_is_held_shrd(struct gfs2_glock *gl)
	{
	return gl->gl_state == LM_ST_SHARED;
	}

	static inline struct address_space gfs2_glock2aspace(struct gfs2_glock gl)
	{
	if (gl->gl_ops->go_flags & GLOF_ASPACE)
	return (struct address_space *)(gl + 1);
	return NULL;
	}

	extern int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number,
	const struct gfs2_glock_operations *glops,
	int create, struct gfs2_glock **glp);
	extern void gfs2_glock_hold(struct gfs2_glock *gl);
	extern void gfs2_glock_put(struct gfs2_glock *gl);
	extern void gfs2_glock_queue_put(struct gfs2_glock *gl);
	extern void gfs2_holder_init(struct gfs2_glock *gl, unsigned int state,
	u16 flags, struct gfs2_holder *gh);
	extern void gfs2_holder_reinit(unsigned int state, u16 flags,
	struct gfs2_holder *gh);
	extern void gfs2_holder_uninit(struct gfs2_holder *gh);
	extern int gfs2_glock_nq(struct gfs2_holder *gh);
	extern int gfs2_glock_poll(struct gfs2_holder *gh);
	extern int gfs2_glock_wait(struct gfs2_holder *gh);
	extern void gfs2_glock_dq(struct gfs2_holder *gh);
	extern void gfs2_glock_dq_wait(struct gfs2_holder *gh);
	extern void gfs2_glock_dq_uninit(struct gfs2_holder *gh);
	extern 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);
	extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
	extern void gfs2_dump_glock(struct seq_file seq, struct gfs2_glock gl);
	#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { gfs2_dump_glock(NULL, gl); BUG(); } } while(0)
	extern __printf(2, 3)
	void gfs2_print_dbg(struct seq_file seq, const char fmt, ...);

	/**
	* gfs2_glock_nq_init - initialize a holder and enqueue it on a glock
	* @gl: the glock
	* @state: the state we're requesting
	* @flags: the modifier flags
	* @gh: the holder structure
	*
	* Returns: 0, GLR_*, or errno
	*/

	static inline int gfs2_glock_nq_init(struct gfs2_glock *gl,
	unsigned int state, u16 flags,
	struct gfs2_holder *gh)
	{
	int error;

	gfs2_holder_init(gl, state, flags, gh);

	error = gfs2_glock_nq(gh);
	if (error)
	gfs2_holder_uninit(gh);

	return error;
	}

	extern void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state);
	extern void gfs2_glock_complete(struct gfs2_glock *gl, int ret);
	extern void gfs2_gl_hash_clear(struct gfs2_sbd *sdp);
	extern void gfs2_glock_finish_truncate(struct gfs2_inode *ip);
	extern void gfs2_glock_thaw(struct gfs2_sbd *sdp);
	extern void gfs2_glock_add_to_lru(struct gfs2_glock *gl);
	extern void gfs2_glock_free(struct gfs2_glock *gl);

	extern int __init gfs2_glock_init(void);
	extern void gfs2_glock_exit(void);

	extern void gfs2_create_debugfs_file(struct gfs2_sbd *sdp);
	extern void gfs2_delete_debugfs_file(struct gfs2_sbd *sdp);
	extern void gfs2_register_debugfs(void);
	extern void gfs2_unregister_debugfs(void);

	extern const struct lm_lockops gfs2_dlm_ops;

	static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh)
	{
	gh->gh_gl = NULL;
	}

	static inline bool gfs2_holder_initialized(struct gfs2_holder *gh)
	{
	return gh->gh_gl;
	}

	/**
	* glock_set_object - set the gl_object field of a glock
	* @gl: the glock
	* @object: the object
	*/
	static inline void glock_set_object(struct gfs2_glock gl, void object)
	{
	spin_lock(&gl->gl_lockref.lock);
	if (gfs2_assert_warn(gl->gl_name.ln_sbd, gl->gl_object == NULL))
	gfs2_dump_glock(NULL, gl);
	gl->gl_object = object;
	spin_unlock(&gl->gl_lockref.lock);
	}

	/**
	* glock_clear_object - clear the gl_object field of a glock
	* @gl: the glock
	* @object: the object
	*
	* I'd love to similarly add this:
	* else if (gfs2_assert_warn(gl->gl_sbd, gl->gl_object == object))
	* gfs2_dump_glock(NULL, gl);
	* Unfortunately, that's not possible because as soon as gfs2_delete_inode
	* frees the block in the rgrp, another process can reassign it for an I_NEW
	* inode in gfs2_create_inode because that calls new_inode, not gfs2_iget.
	* That means gfs2_delete_inode may subsequently try to call this function
	* for a glock that's already pointing to a brand new inode. If we clear the
	* new inode's gl_object, we'll introduce metadata corruption. Function
	* gfs2_delete_inode calls clear_inode which calls gfs2_clear_inode which also
	* tries to clear gl_object, so it's more than just gfs2_delete_inode.
	*
	*/
	static inline void glock_clear_object(struct gfs2_glock gl, void object)
	{
	spin_lock(&gl->gl_lockref.lock);
	if (gl->gl_object == object)
	gl->gl_object = NULL;
	spin_unlock(&gl->gl_lockref.lock);
	}

	#endif /* __GLOCK_DOT_H__ */