NetBSD/sys/dev/raidframe/rf_stripelocks.h

170 lines
7.9 KiB
C

/* $NetBSD: rf_stripelocks.h,v 1.1 1998/11/13 04:20:34 oster Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Mark Holland
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/* :
* Log: rf_stripelocks.h,v
* Revision 1.22 1996/06/10 11:55:47 jimz
* Straightened out some per-array/not-per-array distinctions, fixed
* a couple bugs related to confusion. Added shutdown lists. Removed
* layout shutdown function (now subsumed by shutdown lists).
*
* Revision 1.21 1996/06/07 21:33:04 jimz
* begin using consistent types for sector numbers,
* stripe numbers, row+col numbers, recon unit numbers
*
* Revision 1.20 1996/06/05 18:06:02 jimz
* Major code cleanup. The Great Renaming is now done.
* Better modularity. Better typing. Fixed a bunch of
* synchronization bugs. Made a lot of global stuff
* per-desc or per-array. Removed dead code.
*
* Revision 1.19 1996/05/30 11:29:41 jimz
* Numerous bug fixes. Stripe lock release code disagreed with the taking code
* about when stripes should be locked (I made it consistent: no parity, no lock)
* There was a lot of extra serialization of I/Os which I've removed- a lot of
* it was to calculate values for the cache code, which is no longer with us.
* More types, function, macro cleanup. Added code to properly quiesce the array
* on shutdown. Made a lot of stuff array-specific which was (bogusly) general
* before. Fixed memory allocation, freeing bugs.
*
* Revision 1.18 1996/05/27 18:56:37 jimz
* more code cleanup
* better typing
* compiles in all 3 environments
*
* Revision 1.17 1996/05/24 22:17:04 jimz
* continue code + namespace cleanup
* typed a bunch of flags
*
* Revision 1.16 1996/05/23 21:46:35 jimz
* checkpoint in code cleanup (release prep)
* lots of types, function names have been fixed
*
* Revision 1.15 1996/05/23 00:33:23 jimz
* code cleanup: move all debug decls to rf_options.c, all extern
* debug decls to rf_options.h, all debug vars preceded by rf_
*
* Revision 1.14 1996/05/18 19:51:34 jimz
* major code cleanup- fix syntax, make some types consistent,
* add prototypes, clean out dead code, et cetera
*
* Revision 1.13 1996/05/06 22:08:46 wvcii
* added copyright info and change log
*
*/
/*****************************************************************************
*
* stripelocks.h -- header file for locking stripes
*
* Note that these functions are called from the execution routines of certain
* DAG Nodes, and so they must be NON-BLOCKING to assure maximum parallelism
* in the DAG. Accordingly, when a node wants to acquire a lock, it calls
* AcquireStripeLock, supplying a pointer to a callback function. If the lock
* is free at the time of the call, 0 is returned, indicating that the lock
* has been acquired. If the lock is not free, 1 is returned, and a copy of
* the function pointer and argument are held in the lock table. When the
* lock becomes free, the callback function is invoked.
*
*****************************************************************************/
#ifndef _RF__RF_STRIPELOCKS_H_
#define _RF__RF_STRIPELOCKS_H_
#include <sys/buf.h>
#include "rf_types.h"
#include "rf_threadstuff.h"
#include "rf_general.h"
struct RF_LockReqDesc_s {
RF_IoType_t type; /* read or write */
RF_int64 start, stop; /* start and end of range to be locked */
RF_int64 start2, stop2; /* start and end of 2nd range to be locked */
void (*cbFunc)(struct buf *);/* callback function */
void *cbArg; /* argument to callback function */
RF_LockReqDesc_t *next; /* next element in chain */
RF_LockReqDesc_t *templink; /* for making short-lived lists of request descriptors */
};
#define RF_ASSERT_VALID_LOCKREQ(_lr_) { \
RF_ASSERT(RF_IO_IS_R_OR_W((_lr_)->type)); \
}
struct RF_StripeLockDesc_s {
RF_StripeNum_t stripeID; /* the stripe ID */
RF_LockReqDesc_t *granted; /* unordered list of granted requests */
RF_LockReqDesc_t *waitersH; /* FIFO queue of all waiting reqs, both read and write (Head and Tail) */
RF_LockReqDesc_t *waitersT;
int nWriters; /* number of writers either granted or waiting */
RF_StripeLockDesc_t *next; /* for hash table collision resolution */
};
struct RF_LockTableEntry_s {
RF_DECLARE_MUTEX(mutex) /* mutex on this hash chain */
RF_StripeLockDesc_t *descList; /* hash chain of lock descriptors */
};
/*
* Initializes a stripe lock descriptor. _defSize is the number of sectors
* that we lock when there is no parity information in the ASM (e.g. RAID0).
*/
#define RF_INIT_LOCK_REQ_DESC(_lrd, _typ, _cbf, _cba, _asm, _defSize) \
{ \
(_lrd).type = _typ; \
(_lrd).start2 = -1; \
(_lrd).stop2 = -1; \
if ((_asm)->parityInfo) { \
(_lrd).start = (_asm)->parityInfo->startSector; \
(_lrd).stop = (_asm)->parityInfo->startSector + (_asm)->parityInfo->numSector-1; \
if ((_asm)->parityInfo->next) { \
(_lrd).start2 = (_asm)->parityInfo->next->startSector; \
(_lrd).stop2 = (_asm)->parityInfo->next->startSector + (_asm)->parityInfo->next->numSector-1; \
} \
} else { \
(_lrd).start = 0; \
(_lrd).stop = (_defSize); \
} \
(_lrd).templink= NULL; \
(_lrd).cbFunc = (_cbf); \
(_lrd).cbArg = (void *) (_cba); \
}
int rf_ConfigureStripeLockFreeList(RF_ShutdownList_t **listp);
RF_LockTableEntry_t *rf_MakeLockTable(void);
void rf_ShutdownStripeLocks(RF_LockTableEntry_t *lockTable);
int rf_ConfigureStripeLocks(RF_ShutdownList_t **listp, RF_Raid_t *raidPtr,
RF_Config_t *cfgPtr);
int rf_AcquireStripeLock(RF_LockTableEntry_t *lockTable,
RF_StripeNum_t stripeID, RF_LockReqDesc_t *lockReqDesc);
void rf_ReleaseStripeLock(RF_LockTableEntry_t *lockTable,
RF_StripeNum_t stripeID, RF_LockReqDesc_t *lockReqDesc);
#endif /* !_RF__RF_STRIPELOCKS_H_ */