1 /*        $NetBSD: rf_diskqueue.h,v 1.30 2023/09/17 20:07:39 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  * rf_diskqueue.h -- header file for disk queues
32  *
33  * see comments in rf_diskqueue.c
34  *
35  ****************************************************************************************/
36 
37 
38 #ifndef _RF__RF_DISKQUEUE_H_
39 #define _RF__RF_DISKQUEUE_H_
40 
41 #include <sys/queue.h>
42 
43 #include <dev/raidframe/raidframevar.h>
44 
45 #include "rf_threadstuff.h"
46 #include "rf_acctrace.h"
47 #include "rf_alloclist.h"
48 #include "rf_etimer.h"
49 #include "rf_netbsd.h"
50 
51 
52 #define RF_IO_NORMAL_PRIORITY 1
53 #define RF_IO_LOW_PRIORITY    0
54 
55 /* the data held by a disk queue entry */
56 struct RF_DiskQueueData_s {
57           RF_SectorNum_t sectorOffset;  /* sector offset into the disk */
58           RF_SectorCount_t numSector;   /* number of sectors to read/write */
59           RF_IoType_t type;   /* read/write/nop */
60           void *buf;                    /* buffer pointer */
61           RF_StripeNum_t parityStripeID;          /* the RAID parity stripe ID this
62                                                    * access is for */
63           RF_ReconUnitNum_t which_ru;   /* which RU within this parity stripe */
64           int     priority;   /* the priority of this request */
65           void    (*CompleteFunc) (void *, int);  /* function to be called upon
66                                                              * completion */
67           void   *argument;   /* argument to be passed to CompleteFunc */
68           RF_Raid_t *raidPtr; /* needed for simulation */
69           RF_AccTraceEntry_t *tracerec; /* perf mon only */
70           RF_Etimer_t qtime;  /* perf mon only - time request is in queue */
71           RF_DiskQueueData_t *next;
72           RF_DiskQueueData_t *prev;
73           RF_DiskQueue_t *queue;        /* the disk queue to which this req is
74                                          * targeted */
75           RF_DiskQueueDataFlags_t flags;          /* flags controlling operation */
76 
77           struct buf *bp;               /* a bp to use to get this I/O done */
78           /* TAILQ bits for a queue for completed I/O requests */
79           TAILQ_ENTRY(RF_DiskQueueData_s) iodone_entries;
80           int  error;             /* Indicate if an error occurred
81                                            on this I/O (1=yes, 0=no) */
82 };
83 
84 /* note: "Create" returns type-specific queue header pointer cast to (void *) */
85 struct RF_DiskQueueSW_s {
86           RF_DiskQueueType_t queueType;
87           void   *(*Create) (RF_SectorCount_t, RF_AllocListElem_t *, RF_ShutdownList_t **);         /* creation routine --
88                                                                                                                          * one call per queue in
89                                                                                                                          * system */
90           void    (*Enqueue) (void *, RF_DiskQueueData_t *, int);     /* enqueue routine */
91           RF_DiskQueueData_t *(*Dequeue) (void *);          /* dequeue routine */
92 
93           /* the rest are optional:  they improve performance, but the driver
94            * will deal with it if they don't exist */
95           int     (*Promote) (void *, RF_StripeNum_t, RF_ReconUnitNum_t);       /* promotes priority of
96                                                                                            * tagged accesses */
97 };
98 
99 struct RF_DiskQueue_s {
100           const RF_DiskQueueSW_t *qPtr; /* access point to queue functions */
101           void   *qHdr;                 /* queue header, of whatever type */
102           rf_declare_mutex2(mutex);/* mutex locking data structures */
103           long    numOutstanding;       /* number of I/Os currently outstanding on
104                                          * disk */
105           long    maxOutstanding;       /* max # of I/Os that can be outstanding on a
106                                          * disk (in-kernel only) */
107           int     curPriority;          /* the priority of accs all that are currently
108                                          * outstanding */
109           long    queueLength;          /* number of requests in queue */
110           RF_DiskQueueFlags_t flags;    /* terminate, locked */
111           RF_Raid_t *raidPtr; /* associated array */
112           dev_t   dev;                  /* device number for kernel version */
113           RF_SectorNum_t last_deq_sector;         /* last sector number dequeued or
114                                                    * dispatched */
115           int     col;        /* debug only */
116           struct raidcinfo *rf_cinfo;   /* disks component info.. */
117 };
118 #define RF_DQ_LOCKED  0x02    /* no new accs allowed until queue is
119                                          * explicitly unlocked */
120 
121 /* macros setting & returning information about queues and requests */
122 #define RF_QUEUE_EMPTY(_q)                  ((_q)->numOutstanding == 0)
123 #define RF_QUEUE_FULL(_q)                   ((_q)->numOutstanding == (_q)->maxOutstanding)
124 
125 #define RF_LOCK_QUEUE_MUTEX(_q_,_wh_)   rf_lock_mutex2((_q_)->mutex)
126 #define RF_UNLOCK_QUEUE_MUTEX(_q_,_wh_) rf_unlock_mutex2((_q_)->mutex)
127 
128 /* whether it is ok to dispatch a regular request */
129 #define RF_OK_TO_DISPATCH(_q_,_r_) \
130   (RF_QUEUE_EMPTY(_q_) || \
131     (!RF_QUEUE_FULL(_q_) && ((_r_)->priority >= (_q_)->curPriority)))
132 
133 int rf_ConfigureDiskQueueSystem(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
134 int rf_ConfigureDiskQueues(RF_ShutdownList_t **, RF_Raid_t *, RF_Config_t *);
135 void rf_DiskIOEnqueue(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
136 void rf_DiskIOComplete(RF_DiskQueue_t *, RF_DiskQueueData_t *, int);
137 int rf_DiskIOPromote(RF_DiskQueue_t *, RF_StripeNum_t,  RF_ReconUnitNum_t);
138 RF_DiskQueueData_t *rf_CreateDiskQueueData(RF_IoType_t, RF_SectorNum_t,
139                                                      RF_SectorCount_t , void *,
140                                                      RF_StripeNum_t, RF_ReconUnitNum_t,
141                                                      void (*wakeF) (void *, int),
142                                                      void *,
143                                                      RF_AccTraceEntry_t *, RF_Raid_t *,
144                                                      RF_DiskQueueDataFlags_t,
145                                                      const struct buf *);
146 void rf_FreeDiskQueueData(RF_DiskQueueData_t *);
147 int rf_ConfigureDiskQueue(RF_Raid_t *, RF_DiskQueue_t *,
148                                 RF_RowCol_t, const RF_DiskQueueSW_t *,
149                                 RF_SectorCount_t, dev_t, int,
150                                 RF_ShutdownList_t **,
151                                 RF_AllocListElem_t *);
152 int rf_UpdateDiskQueue(RF_DiskQueue_t *, RF_RaidDisk_t *);
153 
154 #endif                                  /* !_RF__RF_DISKQUEUE_H_ */
155