/* $NetBSD: rf_psstatus.h,v 1.16 2021/07/23 00:54:45 oster Exp $ */

/* $NetBSD: rf_psstatus.h,v 1.16 2021/07/23 00:54:45 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 [email protected]
* 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.
*/

/*****************************************************************************
*
* psstatus.h
*
* The reconstruction code maintains a bunch of status related to the parity
* stripes that are currently under reconstruction. This header file defines
* the status structures.
*
*****************************************************************************/

#ifndef _RF__RF_PSSTATUS_H_
#define _RF__RF_PSSTATUS_H_

#include <dev/raidframe/raidframevar.h>

#include "rf_threadstuff.h"
#include "rf_callback.h"

#define RF_PS_MAX_BUFS 10 /* max number of bufs we'll accumulate before
* we do an XOR */

#define RF_PSS_DEFAULT_TABLESIZE 200

/*
* Macros to acquire/release the mutex lock on a parity stripe status
* descriptor. Note that we use just one lock for the whole hash chain.
*/
#define RF_HASH_PSID(_raid_,_psid_) ( (_psid_) % ((_raid_)->pssTableSize) ) /* simple hash function */
#define RF_LOCK_PSS_MUTEX(_raidPtr, _psid) \
do { \
rf_lock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex); \
while((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock) { \
rf_wait_cond2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].cond,\
(_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);\
} \
(_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock = 1; \
rf_unlock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);\
} while (0);

#define RF_UNLOCK_PSS_MUTEX(_raidPtr, _psid) \
rf_lock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex); \
(_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock = 0; \
rf_broadcast_cond2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].cond); \
rf_unlock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);

struct RF_ReconParityStripeStatus_s {
RF_StripeNum_t parityStripeID; /* the parity stripe ID */
RF_ReconUnitNum_t which_ru; /* which reconstruction unit with the
* indicated parity stripe */
RF_PSSFlags_t flags; /* flags indicating various conditions */
void *rbuf; /* this is the accumulating xor sum */
void *writeRbuf; /* DEBUG ONLY: a pointer to the rbuf after it
* has filled & been sent to disk */
void *rbufsForXor[RF_PS_MAX_BUFS]; /* these are buffers still to
* be xored into the
* accumulating sum */
int xorBufCount; /* num buffers waiting to be xored */
int blockCount; /* count of # proc that have blocked recon on
* this parity stripe */
char issued[RF_MAXCOL]; /* issued[i]==1 <=> column i has already
* issued a read request for the indicated RU */
RF_CallbackFuncDesc_t *procWaitList; /* list of user procs waiting
* for recon to be done */
RF_CallbackValueDesc_t *blockWaitList; /* list of disks blocked
* waiting for user write to
* complete */
RF_CallbackValueDesc_t *bufWaitList; /* list of disks blocked waiting to
* acquire a buffer for this RU */
RF_ReconParityStripeStatus_t *next;
};

struct RF_PSStatusHeader_s {
rf_declare_mutex2(mutex); /* mutex for this hash chain */
rf_declare_cond2(cond); /* and cv for it */
int lock; /* 1 if this hash chain is locked,
0 otherwise */
RF_ReconParityStripeStatus_t *chain; /* the hash chain */
};
/* masks for the "flags" field above */
#define RF_PSS_NONE 0x00000000 /* no flags */
#define RF_PSS_UNDER_RECON 0x00000001 /* this parity stripe is
* currently under
* reconstruction */
#define RF_PSS_FORCED_ON_WRITE 0x00000002 /* indicates a recon was
* forced due to a user-write
* operation */
#define RF_PSS_FORCED_ON_READ 0x00000004 /* ditto for read, but not
* currently implemented */
#define RF_PSS_RECON_BLOCKED 0x00000008 /* reconstruction is currently
* blocked due to a pending
* user I/O */
#define RF_PSS_CREATE 0x00000010 /* tells LookupRUStatus to
* create the entry */
#define RF_PSS_BUFFERWAIT 0x00000020 /* someone is waiting for a
* buffer for this RU */

int rf_ConfigurePSStatus(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
void rf_InitPSStatus(RF_Raid_t *);
RF_PSStatusHeader_t *rf_MakeParityStripeStatusTable(RF_Raid_t *);
void rf_FreeParityStripeStatusTable(RF_Raid_t *, RF_PSStatusHeader_t *);
RF_ReconParityStripeStatus_t *rf_LookupRUStatus(RF_Raid_t *, RF_PSStatusHeader_t *,
RF_StripeNum_t, RF_ReconUnitNum_t,
RF_PSSFlags_t,
RF_ReconParityStripeStatus_t *);
void rf_PSStatusDelete(RF_Raid_t *, RF_PSStatusHeader_t *,
RF_ReconParityStripeStatus_t *);
void rf_RemoveFromActiveReconTable(RF_Raid_t *, RF_StripeNum_t, RF_ReconUnitNum_t);
RF_ReconParityStripeStatus_t *rf_AllocPSStatus(RF_Raid_t *);
void rf_FreePSStatus(RF_Raid_t *, RF_ReconParityStripeStatus_t *);
void rf_PrintPSStatusTable(RF_Raid_t *);

#endif /* !_RF__RF_PSSTATUS_H_ */