1/*	$NetBSD: rf_psstatus.h,v 1.16 2021/07/23 00:54:45 oster Exp $	*/
2/*
3 * Copyright (c) 1995 Carnegie-Mellon University.
4 * All rights reserved.
5 *
6 * Author: Mark Holland
7 *
8 * Permission to use, copy, modify and distribute this software and
9 * its documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
13 *
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
16 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17 *
18 * Carnegie Mellon requests users of this software to return to
19 *
20 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21 *  School of Computer Science
22 *  Carnegie Mellon University
23 *  Pittsburgh PA 15213-3890
24 *
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
27 */
28
29/*****************************************************************************
30 *
31 * psstatus.h
32 *
33 * The reconstruction code maintains a bunch of status related to the parity
34 * stripes that are currently under reconstruction.  This header file defines
35 * the status structures.
36 *
37 *****************************************************************************/
38
39#ifndef _RF__RF_PSSTATUS_H_
40#define _RF__RF_PSSTATUS_H_
41
42#include <dev/raidframe/raidframevar.h>
43
44#include "rf_threadstuff.h"
45#include "rf_callback.h"
46
47#define RF_PS_MAX_BUFS 10	/* max number of bufs we'll accumulate before
48				 * we do an XOR */
49
50#define RF_PSS_DEFAULT_TABLESIZE 200
51
52/*
53 * Macros to acquire/release the mutex lock on a parity stripe status
54 * descriptor. Note that we use just one lock for the whole hash chain.
55 */
56#define RF_HASH_PSID(_raid_,_psid_) ( (_psid_) % ((_raid_)->pssTableSize) )	/* simple hash function */
57#define RF_LOCK_PSS_MUTEX(_raidPtr, _psid)                                                      \
58  do {                                                                                          \
59     rf_lock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);  \
60     while((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock) {           \
61          rf_wait_cond2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].cond,\
62	                (_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);\
63     }                                                                                          \
64     (_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock = 1;               \
65     rf_unlock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);\
66  } while (0);
67
68#define RF_UNLOCK_PSS_MUTEX(_raidPtr, _psid)                                                    \
69  rf_lock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);     \
70  (_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].lock = 0;                  \
71  rf_broadcast_cond2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].cond);  \
72  rf_unlock_mutex2((_raidPtr)->reconControl->pssTable[ RF_HASH_PSID(_raidPtr,_psid) ].mutex);
73
74struct RF_ReconParityStripeStatus_s {
75	RF_StripeNum_t parityStripeID;	/* the parity stripe ID */
76	RF_ReconUnitNum_t which_ru;	/* which reconstruction unit with the
77					 * indicated parity stripe */
78	RF_PSSFlags_t flags;	/* flags indicating various conditions */
79	void   *rbuf;		/* this is the accumulating xor sum */
80	void   *writeRbuf;	/* DEBUG ONLY:  a pointer to the rbuf after it
81				 * has filled & been sent to disk */
82	void   *rbufsForXor[RF_PS_MAX_BUFS];	/* these are buffers still to
83						 * be xored into the
84						 * accumulating sum */
85	int     xorBufCount;	/* num buffers waiting to be xored */
86	int     blockCount;	/* count of # proc that have blocked recon on
87				 * this parity stripe */
88	char   issued[RF_MAXCOL];	/* issued[i]==1 <=> column i has already
89				 * issued a read request for the indicated RU */
90	RF_CallbackFuncDesc_t *procWaitList;	/* list of user procs waiting
91						 * for recon to be done */
92	RF_CallbackValueDesc_t *blockWaitList;	/* list of disks blocked
93						 * waiting for user write to
94						 * complete */
95	RF_CallbackValueDesc_t *bufWaitList;	/* list of disks blocked waiting to
96					 * acquire a buffer for this RU */
97	RF_ReconParityStripeStatus_t *next;
98};
99
100struct RF_PSStatusHeader_s {
101	rf_declare_mutex2(mutex);	/* mutex for this hash chain */
102	rf_declare_cond2(cond);		/* and cv for it */
103	int lock;             		/* 1 if this hash chain is locked,
104					   0 otherwise */
105	RF_ReconParityStripeStatus_t *chain;	/* the hash chain */
106};
107/* masks for the "flags" field above */
108#define RF_PSS_NONE            0x00000000	/* no flags */
109#define RF_PSS_UNDER_RECON     0x00000001	/* this parity stripe is
110						 * currently under
111						 * reconstruction */
112#define RF_PSS_FORCED_ON_WRITE 0x00000002	/* indicates a recon was
113						 * forced due to a user-write
114						 * operation */
115#define RF_PSS_FORCED_ON_READ  0x00000004	/* ditto for read, but not
116						 * currently implemented */
117#define RF_PSS_RECON_BLOCKED   0x00000008	/* reconstruction is currently
118						 * blocked due to a pending
119						 * user I/O */
120#define RF_PSS_CREATE          0x00000010	/* tells LookupRUStatus to
121						 * create the entry */
122#define RF_PSS_BUFFERWAIT      0x00000020	/* someone is waiting for a
123						 * buffer for this RU */
124
125int rf_ConfigurePSStatus(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
126void rf_InitPSStatus(RF_Raid_t *);
127RF_PSStatusHeader_t *rf_MakeParityStripeStatusTable(RF_Raid_t *);
128void rf_FreeParityStripeStatusTable(RF_Raid_t *, RF_PSStatusHeader_t *);
129RF_ReconParityStripeStatus_t *rf_LookupRUStatus(RF_Raid_t *, RF_PSStatusHeader_t *,
130						RF_StripeNum_t, RF_ReconUnitNum_t,
131						RF_PSSFlags_t,
132						RF_ReconParityStripeStatus_t *);
133void rf_PSStatusDelete(RF_Raid_t *, RF_PSStatusHeader_t *,
134		       RF_ReconParityStripeStatus_t *);
135void rf_RemoveFromActiveReconTable(RF_Raid_t *, RF_StripeNum_t, RF_ReconUnitNum_t);
136RF_ReconParityStripeStatus_t *rf_AllocPSStatus(RF_Raid_t *);
137void rf_FreePSStatus(RF_Raid_t *, RF_ReconParityStripeStatus_t *);
138void rf_PrintPSStatusTable(RF_Raid_t *);
139
140#endif				/* !_RF__RF_PSSTATUS_H_ */
141