1/*	$NetBSD: rf_reconstruct.h,v 1.32 2023/05/27 21:38:06 andvar 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 * rf_reconstruct.h -- header file for reconstruction code
31 *********************************************************/
32
33#ifndef _RF__RF_RECONSTRUCT_H_
34#define _RF__RF_RECONSTRUCT_H_
35
36#include <dev/raidframe/raidframevar.h>
37#include <sys/time.h>
38#include "rf_reconmap.h"
39#include "rf_psstatus.h"
40
41/* reconstruction configuration information */
42struct RF_ReconConfig_s {
43	unsigned numFloatingReconBufs;	/* number of floating recon bufs to
44					 * use */
45	RF_HeadSepLimit_t headSepLimit;	/* how far apart the heads are allow
46					 * to become, in parity stripes */
47};
48/* a reconstruction buffer */
49struct RF_ReconBuffer_s {
50	RF_Raid_t *raidPtr;	/* void *to avoid recursive includes */
51	void *buffer;		/* points to the data */
52	RF_StripeNum_t parityStripeID;	/* the parity stripe that this data
53					 * relates to */
54	int     which_ru;	/* which reconstruction unit within the PSS */
55	RF_SectorNum_t failedDiskSectorOffset;	/* the offset into the failed
56						 * disk */
57	RF_RowCol_t col;	/* which disk this buffer belongs to or is
58				 * targeted at */
59	RF_StripeCount_t count;	/* counts the # of SUs installed so far */
60	int     priority;	/* used to force hi priority recon */
61	RF_RbufType_t type;	/* FORCED or FLOATING */
62	RF_ReconBuffer_t *next;	/* used for buffer management */
63	void   *arg;		/* generic field for general use */
64	RF_RowCol_t spRow, spCol;	/* spare disk to which this buf should
65					 * be written */
66	/* if dist sparing off, always identifies the replacement disk */
67	RF_SectorNum_t spOffset;/* offset into the spare disk */
68	/* if dist sparing off, identical to failedDiskSectorOffset */
69	RF_ReconParityStripeStatus_t *pssPtr;	/* debug- pss associated with
70						 * issue-pending write */
71};
72/* a reconstruction event descriptor.  The event types currently are:
73 *    RF_REVENT_READDONE    -- a read operation has completed
74 *    RF_REVENT_WRITEDONE   -- a write operation has completed
75 *    RF_REVENT_BUFREADY    -- the buffer manager has produced a full buffer
76 *    RF_REVENT_BLOCKCLEAR  -- a reconstruction blockage has been cleared
77 *    RF_REVENT_BUFCLEAR    -- the buffer manager has released a process blocked on submission
78 *    RF_REVENT_SKIP        -- we need to skip the current RU and go on to the next one, typ. b/c we found recon forced
79 *    RF_REVENT_FORCEDREADONE- a forced-reconstruction read operation has completed
80 */
81typedef enum RF_Revent_e {
82	RF_REVENT_READDONE,
83	RF_REVENT_WRITEDONE,
84	RF_REVENT_BUFREADY,
85	RF_REVENT_BLOCKCLEAR,
86	RF_REVENT_BUFCLEAR,
87	RF_REVENT_HEADSEPCLEAR,
88	RF_REVENT_SKIP,
89	RF_REVENT_FORCEDREADDONE,
90	RF_REVENT_READ_FAILED,
91	RF_REVENT_WRITE_FAILED,
92	RF_REVENT_FORCEDREAD_FAILED
93}       RF_Revent_t;
94
95struct RF_ReconEvent_s {
96	RF_Revent_t type;	/* what kind of event has occurred */
97	RF_RowCol_t col;	/* row ID is implicit in the queue in which
98				 * the event is placed */
99	void   *arg;		/* a generic argument */
100	RF_ReconEvent_t *next;
101};
102/*
103 * Reconstruction control information maintained per-disk
104 * (for surviving disks)
105 */
106struct RF_PerDiskReconCtrl_s {
107	RF_ReconCtrl_t *reconCtrl;
108	RF_RowCol_t col;	/* to make this structure self-identifying */
109	RF_StripeNum_t curPSID;	/* the next parity stripe ID to check on this
110				 * disk */
111	RF_HeadSepLimit_t headSepCounter;	/* counter used to control
112						 * maximum head separation */
113	RF_SectorNum_t diskOffset;	/* the offset into the indicated disk
114					 * of the current PU */
115	RF_ReconUnitNum_t ru_count;	/* this counts off the recon units
116					 * within each parity unit */
117	RF_ReconBuffer_t *rbuf;	/* the recon buffer assigned to this disk */
118};
119/* main reconstruction control structure */
120struct RF_ReconCtrl_s {
121	RF_RaidReconDesc_t *reconDesc;
122	RF_RowCol_t fcol;	/* which column has failed */
123	RF_PerDiskReconCtrl_t *perDiskInfo;	/* information maintained
124						 * per-disk */
125	RF_ReconMap_t *reconMap;/* map of what has/has not been reconstructed */
126	RF_RowCol_t spareCol;   /* which of the spare disks we're using */
127	RF_StripeNum_t lastPSID;/* the ID of the last parity stripe we want
128				 * reconstructed */
129	int     percentComplete;/* percentage completion of reconstruction */
130	RF_ReconUnitCount_t  numRUsComplete; /* number of Reconstruction Units done */
131	RF_ReconUnitCount_t  numRUsTotal;    /* total number of Reconstruction Units */
132	int error;              /* non-0 indicates that an error has
133				   occurred during reconstruction, and
134				   the reconstruction is in the process of
135				   bailing out. */
136
137	/* reconstruction event queue */
138	RF_ReconEvent_t *eventQueue;	/* queue of pending reconstruction
139					 * events */
140	rf_declare_mutex2(eq_mutex);	/* mutex for locking event */
141	rf_declare_cond2(eq_cv);	/* queue */
142	int     eq_count;	/* debug only */
143
144	/* reconstruction buffer management */
145	rf_declare_mutex2(rb_mutex);	        /* mutex/cv for messing */
146	rf_declare_cond2(rb_cv);		/* around with recon buffers */
147	int rb_lock;                            /* 1 if someone is mucking
148						   with recon buffers,
149						   0 otherwise */
150	int pending_writes;			/* number of writes which
151						   have not completed */
152	RF_ReconBuffer_t *floatingRbufs;	/* available floating
153						 * reconstruction buffers */
154	RF_ReconBuffer_t *committedRbufs;	/* recon buffers that have
155						 * been committed to some
156						 * waiting disk */
157	RF_ReconBuffer_t *fullBufferList;	/* full buffers waiting to be
158						 * written out */
159	RF_CallbackValueDesc_t *bufferWaitList;	/* disks that are currently
160						 * blocked waiting for buffers */
161
162	/* parity stripe status table */
163	RF_PSStatusHeader_t *pssTable;	/* stores the reconstruction status of
164					 * active parity stripes */
165
166	/* maximum-head separation control */
167	RF_HeadSepLimit_t minHeadSepCounter;	/* the minimum hs counter over
168						 * all disks */
169	RF_CallbackValueDesc_t *headSepCBList;	/* list of callbacks to be
170						 * done as minPSID advances */
171
172	/* performance monitoring */
173	struct timeval starttime;	/* recon start time */
174};
175/* the default priority for reconstruction accesses */
176#define RF_IO_RECON_PRIORITY RF_IO_LOW_PRIORITY
177
178int rf_ConfigureReconstruction(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
179int rf_ReconstructFailedDisk(RF_Raid_t *, RF_RowCol_t);
180int rf_ReconstructFailedDiskBasic(RF_Raid_t *, RF_RowCol_t);
181int rf_ReconstructInPlace(RF_Raid_t *, RF_RowCol_t);
182int rf_ContinueReconstructFailedDisk(RF_RaidReconDesc_t *);
183int rf_ForceOrBlockRecon(RF_Raid_t *, RF_AccessStripeMap_t *,
184			 void (*cbFunc) (void *), void *);
185int rf_UnblockRecon(RF_Raid_t *, RF_AccessStripeMap_t *);
186void rf_WakeupHeadSepCBWaiters(RF_Raid_t *);
187
188extern struct pool rf_reconbuffer_pool;
189
190#endif				/* !_RF__RF_RECONSTRUCT_H_ */
191