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Diffstat (limited to 'kernel/include/linux/dlm.h')
| -rw-r--r-- | kernel/include/linux/dlm.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/kernel/include/linux/dlm.h b/kernel/include/linux/dlm.h new file mode 100644 index 000000000..d02da2c6f --- /dev/null +++ b/kernel/include/linux/dlm.h @@ -0,0 +1,172 @@ +/****************************************************************************** +******************************************************************************* +** +** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. +** Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved. +** +** This copyrighted material is made available to anyone wishing to use, +** modify, copy, or redistribute it subject to the terms and conditions +** of the GNU General Public License v.2. +** +******************************************************************************* +******************************************************************************/ +#ifndef __DLM_DOT_H__ +#define __DLM_DOT_H__ + +#include <uapi/linux/dlm.h> + + +struct dlm_slot { + int nodeid; /* 1 to MAX_INT */ + int slot; /* 1 to MAX_INT */ +}; + +/* + * recover_prep: called before the dlm begins lock recovery. + * Notfies lockspace user that locks from failed members will be granted. + * recover_slot: called after recover_prep and before recover_done. + * Identifies a failed lockspace member. + * recover_done: called after the dlm completes lock recovery. + * Identifies lockspace members and lockspace generation number. + */ + +struct dlm_lockspace_ops { + void (*recover_prep) (void *ops_arg); + void (*recover_slot) (void *ops_arg, struct dlm_slot *slot); + void (*recover_done) (void *ops_arg, struct dlm_slot *slots, + int num_slots, int our_slot, uint32_t generation); +}; + +/* + * dlm_new_lockspace + * + * Create/join a lockspace. + * + * name: lockspace name, null terminated, up to DLM_LOCKSPACE_LEN (not + * including terminating null). + * + * cluster: cluster name, null terminated, up to DLM_LOCKSPACE_LEN (not + * including terminating null). Optional. When cluster is null, it + * is not used. When set, dlm_new_lockspace() returns -EBADR if cluster + * is not equal to the dlm cluster name. + * + * flags: + * DLM_LSFL_NODIR + * The dlm should not use a resource directory, but statically assign + * resource mastery to nodes based on the name hash that is otherwise + * used to select the directory node. Must be the same on all nodes. + * DLM_LSFL_TIMEWARN + * The dlm should emit netlink messages if locks have been waiting + * for a configurable amount of time. (Unused.) + * DLM_LSFL_FS + * The lockspace user is in the kernel (i.e. filesystem). Enables + * direct bast/cast callbacks. + * DLM_LSFL_NEWEXCL + * dlm_new_lockspace() should return -EEXIST if the lockspace exists. + * + * lvblen: length of lvb in bytes. Must be multiple of 8. + * dlm_new_lockspace() returns an error if this does not match + * what other nodes are using. + * + * ops: callbacks that indicate lockspace recovery points so the + * caller can coordinate its recovery and know lockspace members. + * This is only used by the initial dlm_new_lockspace() call. + * Optional. + * + * ops_arg: arg for ops callbacks. + * + * ops_result: tells caller if the ops callbacks (if provided) will + * be used or not. 0: will be used, -EXXX will not be used. + * -EOPNOTSUPP: the dlm does not have recovery_callbacks enabled. + * + * lockspace: handle for dlm functions + */ + +int dlm_new_lockspace(const char *name, const char *cluster, + uint32_t flags, int lvblen, + const struct dlm_lockspace_ops *ops, void *ops_arg, + int *ops_result, dlm_lockspace_t **lockspace); + +/* + * dlm_release_lockspace + * + * Stop a lockspace. + */ + +int dlm_release_lockspace(dlm_lockspace_t *lockspace, int force); + +/* + * dlm_lock + * + * Make an asynchronous request to acquire or convert a lock on a named + * resource. + * + * lockspace: context for the request + * mode: the requested mode of the lock (DLM_LOCK_) + * lksb: lock status block for input and async return values + * flags: input flags (DLM_LKF_) + * name: name of the resource to lock, can be binary + * namelen: the length in bytes of the resource name (MAX_RESNAME_LEN) + * parent: the lock ID of a parent lock or 0 if none + * lockast: function DLM executes when it completes processing the request + * astarg: argument passed to lockast and bast functions + * bast: function DLM executes when this lock later blocks another request + * + * Returns: + * 0 if request is successfully queued for processing + * -EINVAL if any input parameters are invalid + * -EAGAIN if request would block and is flagged DLM_LKF_NOQUEUE + * -ENOMEM if there is no memory to process request + * -ENOTCONN if there is a communication error + * + * If the call to dlm_lock returns an error then the operation has failed and + * the AST routine will not be called. If dlm_lock returns 0 it is still + * possible that the lock operation will fail. The AST routine will be called + * when the locking is complete and the status is returned in the lksb. + * + * If the AST routines or parameter are passed to a conversion operation then + * they will overwrite those values that were passed to a previous dlm_lock + * call. + * + * AST routines should not block (at least not for long), but may make + * any locking calls they please. + */ + +int dlm_lock(dlm_lockspace_t *lockspace, + int mode, + struct dlm_lksb *lksb, + uint32_t flags, + void *name, + unsigned int namelen, + uint32_t parent_lkid, + void (*lockast) (void *astarg), + void *astarg, + void (*bast) (void *astarg, int mode)); + +/* + * dlm_unlock + * + * Asynchronously release a lock on a resource. The AST routine is called + * when the resource is successfully unlocked. + * + * lockspace: context for the request + * lkid: the lock ID as returned in the lksb + * flags: input flags (DLM_LKF_) + * lksb: if NULL the lksb parameter passed to last lock request is used + * astarg: the arg used with the completion ast for the unlock + * + * Returns: + * 0 if request is successfully queued for processing + * -EINVAL if any input parameters are invalid + * -ENOTEMPTY if the lock still has sublocks + * -EBUSY if the lock is waiting for a remote lock operation + * -ENOTCONN if there is a communication error + */ + +int dlm_unlock(dlm_lockspace_t *lockspace, + uint32_t lkid, + uint32_t flags, + struct dlm_lksb *lksb, + void *astarg); + +#endif /* __DLM_DOT_H__ */ |