/* 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 int gfs2_glock_async_wait(unsigned int num_gh, struct gfs2_holder *ghs); 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, bool fsid); #define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { \ gfs2_dump_glock(NULL, gl, true); \ 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; } static inline bool gfs2_holder_queued(struct gfs2_holder *gh) { return !list_empty(&gh->gh_list); } /** * 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, true); 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, true); * 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__ */