1/* $NetBSD: rf_psstatus.h,v 1.14 2011/05/03 08:18:43 mrg 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_CallbackDesc_t *procWaitList; /* list of user procs waiting
91 * for recon to be done */
92 RF_CallbackDesc_t *blockWaitList; /* list of disks blocked
93 * waiting for user write to
94 * complete */
95 RF_CallbackDesc_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 **);
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