| /* 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, |
| 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; |
| } |
| |
| /** |
| * 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__ */ |