diff options
Diffstat (limited to 'sys/dev/raidframe/rf_diskqueue.c')
| -rw-r--r-- | sys/dev/raidframe/rf_diskqueue.c | 591 |
1 files changed, 591 insertions, 0 deletions
diff --git a/sys/dev/raidframe/rf_diskqueue.c b/sys/dev/raidframe/rf_diskqueue.c new file mode 100644 index 0000000..3359ae5 --- /dev/null +++ b/sys/dev/raidframe/rf_diskqueue.c @@ -0,0 +1,591 @@ +/* $FreeBSD$ */ +/* $NetBSD: rf_diskqueue.c,v 1.13 2000/03/04 04:22:34 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 Software.Distribution@CS.CMU.EDU + * 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. + */ + +/**************************************************************************** + * + * rf_diskqueue.c -- higher-level disk queue code + * + * the routines here are a generic wrapper around the actual queueing + * routines. The code here implements thread scheduling, synchronization, + * and locking ops (see below) on top of the lower-level queueing code. + * + * to support atomic RMW, we implement "locking operations". When a + * locking op is dispatched to the lower levels of the driver, the + * queue is locked, and no further I/Os are dispatched until the queue + * receives & completes a corresponding "unlocking operation". This + * code relies on the higher layers to guarantee that a locking op + * will always be eventually followed by an unlocking op. The model + * is that the higher layers are structured so locking and unlocking + * ops occur in pairs, i.e. an unlocking op cannot be generated until + * after a locking op reports completion. There is no good way to + * check to see that an unlocking op "corresponds" to the op that + * currently has the queue locked, so we make no such attempt. Since + * by definition there can be only one locking op outstanding on a + * disk, this should not be a problem. + * + * In the kernel, we allow multiple I/Os to be concurrently dispatched + * to the disk driver. In order to support locking ops in this + * environment, when we decide to do a locking op, we stop dispatching + * new I/Os and wait until all dispatched I/Os have completed before + * dispatching the locking op. + * + * Unfortunately, the code is different in the 3 different operating + * states (user level, kernel, simulator). In the kernel, I/O is + * non-blocking, and we have no disk threads to dispatch for us. + * Therefore, we have to dispatch new I/Os to the scsi driver at the + * time of enqueue, and also at the time of completion. At user + * level, I/O is blocking, and so only the disk threads may dispatch + * I/Os. Thus at user level, all we can do at enqueue time is enqueue + * and wake up the disk thread to do the dispatch. + * + ****************************************************************************/ + +#include <dev/raidframe/rf_types.h> +#include <dev/raidframe/rf_threadstuff.h> +#include <dev/raidframe/rf_raid.h> +#include <dev/raidframe/rf_diskqueue.h> +#include <dev/raidframe/rf_alloclist.h> +#include <dev/raidframe/rf_acctrace.h> +#include <dev/raidframe/rf_etimer.h> +#include <dev/raidframe/rf_configure.h> +#include <dev/raidframe/rf_general.h> +#include <dev/raidframe/rf_freelist.h> +#include <dev/raidframe/rf_debugprint.h> +#include <dev/raidframe/rf_shutdown.h> +#include <dev/raidframe/rf_cvscan.h> +#include <dev/raidframe/rf_sstf.h> +#include <dev/raidframe/rf_fifo.h> +#include <dev/raidframe/rf_kintf.h> + +static int init_dqd(RF_DiskQueueData_t *); +static void clean_dqd(RF_DiskQueueData_t *); +static void rf_ShutdownDiskQueueSystem(void *); + +#define Dprintf1(s,a) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),NULL,NULL,NULL,NULL,NULL,NULL,NULL) +#define Dprintf2(s,a,b) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),NULL,NULL,NULL,NULL,NULL,NULL) +#define Dprintf3(s,a,b,c) if (rf_queueDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),NULL,NULL,NULL,NULL,NULL) + +/***************************************************************************** + * + * the disk queue switch defines all the functions used in the + * different queueing disciplines queue ID, init routine, enqueue + * routine, dequeue routine + * + ****************************************************************************/ + +static RF_DiskQueueSW_t diskqueuesw[] = { + {"fifo", /* FIFO */ + rf_FifoCreate, + rf_FifoEnqueue, + rf_FifoDequeue, + rf_FifoPeek, + rf_FifoPromote}, + + {"cvscan", /* cvscan */ + rf_CvscanCreate, + rf_CvscanEnqueue, + rf_CvscanDequeue, + rf_CvscanPeek, + rf_CvscanPromote}, + + {"sstf", /* shortest seek time first */ + rf_SstfCreate, + rf_SstfEnqueue, + rf_SstfDequeue, + rf_SstfPeek, + rf_SstfPromote}, + + {"scan", /* SCAN (two-way elevator) */ + rf_ScanCreate, + rf_SstfEnqueue, + rf_ScanDequeue, + rf_ScanPeek, + rf_SstfPromote}, + + {"cscan", /* CSCAN (one-way elevator) */ + rf_CscanCreate, + rf_SstfEnqueue, + rf_CscanDequeue, + rf_CscanPeek, + rf_SstfPromote}, + +}; +#define NUM_DISK_QUEUE_TYPES (sizeof(diskqueuesw)/sizeof(RF_DiskQueueSW_t)) + +static RF_FreeList_t *rf_dqd_freelist; + +#define RF_MAX_FREE_DQD 256 +#define RF_DQD_INC 16 +#define RF_DQD_INITIAL 64 + +#if defined(__FreeBSD__) && __FreeBSD_version > 500005 +#include <sys/bio.h> +#endif + +#include <sys/buf.h> + +static int +init_dqd(dqd) + RF_DiskQueueData_t *dqd; +{ + + dqd->bp = (RF_Buf_t) malloc(sizeof(RF_Buf_t), M_RAIDFRAME, M_NOWAIT); + if (dqd->bp == NULL) { + return (ENOMEM); + } + memset(dqd->bp, 0, sizeof(RF_Buf_t)); /* if you don't do it, nobody + * else will.. */ + return (0); +} + +static void +clean_dqd(dqd) + RF_DiskQueueData_t *dqd; +{ + free(dqd->bp, M_RAIDFRAME); +} +/* configures a single disk queue */ + +int +rf_ConfigureDiskQueue( + RF_Raid_t * raidPtr, + RF_DiskQueue_t * diskqueue, + RF_RowCol_t r, /* row & col -- debug only. BZZT not any + * more... */ + RF_RowCol_t c, + RF_DiskQueueSW_t * p, + RF_SectorCount_t sectPerDisk, + dev_t dev, + int maxOutstanding, + RF_ShutdownList_t ** listp, + RF_AllocListElem_t * clList) +{ + int rc; + + diskqueue->row = r; + diskqueue->col = c; + diskqueue->qPtr = p; + diskqueue->qHdr = (p->Create) (sectPerDisk, clList, listp); + diskqueue->dev = dev; + diskqueue->numOutstanding = 0; + diskqueue->queueLength = 0; + diskqueue->maxOutstanding = maxOutstanding; + diskqueue->curPriority = RF_IO_NORMAL_PRIORITY; + diskqueue->nextLockingOp = NULL; + diskqueue->unlockingOp = NULL; + diskqueue->numWaiting = 0; + diskqueue->flags = 0; + diskqueue->raidPtr = raidPtr; + diskqueue->rf_cinfo = &raidPtr->raid_cinfo[r][c]; + rc = rf_create_managed_mutex(listp, &diskqueue->mutex); + if (rc) { + RF_ERRORMSG3("Unable to init mutex file %s line %d rc=%d\n", __FILE__, + __LINE__, rc); + return (rc); + } + rc = rf_create_managed_cond(listp, &diskqueue->cond); + if (rc) { + RF_ERRORMSG3("Unable to init cond file %s line %d rc=%d\n", __FILE__, + __LINE__, rc); + return (rc); + } + return (0); +} + +static void +rf_ShutdownDiskQueueSystem(ignored) + void *ignored; +{ + RF_FREELIST_DESTROY_CLEAN(rf_dqd_freelist, next, (RF_DiskQueueData_t *), clean_dqd); +} + +int +rf_ConfigureDiskQueueSystem(listp) + RF_ShutdownList_t **listp; +{ + int rc; + + RF_FREELIST_CREATE(rf_dqd_freelist, RF_MAX_FREE_DQD, + RF_DQD_INC, sizeof(RF_DiskQueueData_t)); + if (rf_dqd_freelist == NULL) + return (ENOMEM); + rc = rf_ShutdownCreate(listp, rf_ShutdownDiskQueueSystem, NULL); + if (rc) { + RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n", + __FILE__, __LINE__, rc); + rf_ShutdownDiskQueueSystem(NULL); + return (rc); + } + RF_FREELIST_PRIME_INIT(rf_dqd_freelist, RF_DQD_INITIAL, next, + (RF_DiskQueueData_t *), init_dqd); + return (0); +} + +int +rf_ConfigureDiskQueues( + RF_ShutdownList_t ** listp, + RF_Raid_t * raidPtr, + RF_Config_t * cfgPtr) +{ + RF_DiskQueue_t **diskQueues, *spareQueues; + RF_DiskQueueSW_t *p; + RF_RowCol_t r, c; + int rc, i; + + raidPtr->maxQueueDepth = cfgPtr->maxOutstandingDiskReqs; + + for (p = NULL, i = 0; i < NUM_DISK_QUEUE_TYPES; i++) { + if (!strcmp(diskqueuesw[i].queueType, cfgPtr->diskQueueType)) { + p = &diskqueuesw[i]; + break; + } + } + if (p == NULL) { + RF_ERRORMSG2("Unknown queue type \"%s\". Using %s\n", cfgPtr->diskQueueType, diskqueuesw[0].queueType); + p = &diskqueuesw[0]; + } + raidPtr->qType = p; + RF_CallocAndAdd(diskQueues, raidPtr->numRow, sizeof(RF_DiskQueue_t *), (RF_DiskQueue_t **), raidPtr->cleanupList); + if (diskQueues == NULL) { + return (ENOMEM); + } + raidPtr->Queues = diskQueues; + for (r = 0; r < raidPtr->numRow; r++) { + RF_CallocAndAdd(diskQueues[r], raidPtr->numCol + + ((r == 0) ? RF_MAXSPARE : 0), + sizeof(RF_DiskQueue_t), (RF_DiskQueue_t *), + raidPtr->cleanupList); + if (diskQueues[r] == NULL) + return (ENOMEM); + for (c = 0; c < raidPtr->numCol; c++) { + rc = rf_ConfigureDiskQueue(raidPtr, &diskQueues[r][c], + r, c, p, + raidPtr->sectorsPerDisk, + raidPtr->Disks[r][c].dev, + cfgPtr->maxOutstandingDiskReqs, + listp, raidPtr->cleanupList); + if (rc) + return (rc); + } + } + + spareQueues = &raidPtr->Queues[0][raidPtr->numCol]; + for (r = 0; r < raidPtr->numSpare; r++) { + rc = rf_ConfigureDiskQueue(raidPtr, &spareQueues[r], + 0, raidPtr->numCol + r, p, + raidPtr->sectorsPerDisk, + raidPtr->Disks[0][raidPtr->numCol + r].dev, + cfgPtr->maxOutstandingDiskReqs, listp, + raidPtr->cleanupList); + if (rc) + return (rc); + } + return (0); +} +/* Enqueue a disk I/O + * + * Unfortunately, we have to do things differently in the different + * environments (simulator, user-level, kernel). + * At user level, all I/O is blocking, so we have 1 or more threads/disk + * and the thread that enqueues is different from the thread that dequeues. + * In the kernel, I/O is non-blocking and so we'd like to have multiple + * I/Os outstanding on the physical disks when possible. + * + * when any request arrives at a queue, we have two choices: + * dispatch it to the lower levels + * queue it up + * + * kernel rules for when to do what: + * locking request: queue empty => dispatch and lock queue, + * else queue it + * unlocking req : always dispatch it + * normal req : queue empty => dispatch it & set priority + * queue not full & priority is ok => dispatch it + * else queue it + * + * user-level rules: + * always enqueue. In the special case of an unlocking op, enqueue + * in a special way that will cause the unlocking op to be the next + * thing dequeued. + * + * simulator rules: + * Do the same as at user level, with the sleeps and wakeups suppressed. + */ +void +rf_DiskIOEnqueue(queue, req, pri) + RF_DiskQueue_t *queue; + RF_DiskQueueData_t *req; + int pri; +{ + RF_ETIMER_START(req->qtime); + RF_ASSERT(req->type == RF_IO_TYPE_NOP || req->numSector); + req->priority = pri; + + if (rf_queueDebug && (req->numSector == 0)) { + printf("Warning: Enqueueing zero-sector access\n"); + } + /* + * kernel + */ + RF_LOCK_QUEUE_MUTEX(queue, "DiskIOEnqueue"); + /* locking request */ + if (RF_LOCKING_REQ(req)) { + if (RF_QUEUE_EMPTY(queue)) { + Dprintf3("Dispatching pri %d locking op to r %d c %d (queue empty)\n", pri, queue->row, queue->col); + RF_LOCK_QUEUE(queue); + rf_DispatchKernelIO(queue, req); + } else { + queue->queueLength++; /* increment count of number + * of requests waiting in this + * queue */ + Dprintf3("Enqueueing pri %d locking op to r %d c %d (queue not empty)\n", pri, queue->row, queue->col); + req->queue = (void *) queue; + (queue->qPtr->Enqueue) (queue->qHdr, req, pri); + } + } + /* unlocking request */ + else + if (RF_UNLOCKING_REQ(req)) { /* we'll do the actual unlock + * when this I/O completes */ + Dprintf3("Dispatching pri %d unlocking op to r %d c %d\n", pri, queue->row, queue->col); + RF_ASSERT(RF_QUEUE_LOCKED(queue)); + rf_DispatchKernelIO(queue, req); + } + /* normal request */ + else + if (RF_OK_TO_DISPATCH(queue, req)) { + Dprintf3("Dispatching pri %d regular op to r %d c %d (ok to dispatch)\n", pri, queue->row, queue->col); + rf_DispatchKernelIO(queue, req); + } else { + queue->queueLength++; /* increment count of + * number of requests + * waiting in this queue */ + Dprintf3("Enqueueing pri %d regular op to r %d c %d (not ok to dispatch)\n", pri, queue->row, queue->col); + req->queue = (void *) queue; + (queue->qPtr->Enqueue) (queue->qHdr, req, pri); + } + RF_UNLOCK_QUEUE_MUTEX(queue, "DiskIOEnqueue"); +} + + +/* get the next set of I/Os started, kernel version only */ +void +rf_DiskIOComplete(queue, req, status) + RF_DiskQueue_t *queue; + RF_DiskQueueData_t *req; + int status; +{ + int done = 0; + + RF_LOCK_QUEUE_MUTEX(queue, "DiskIOComplete"); + + /* unlock the queue: (1) after an unlocking req completes (2) after a + * locking req fails */ + if (RF_UNLOCKING_REQ(req) || (RF_LOCKING_REQ(req) && status)) { + Dprintf2("DiskIOComplete: unlocking queue at r %d c %d\n", queue->row, queue->col); + RF_ASSERT(RF_QUEUE_LOCKED(queue) && (queue->unlockingOp == NULL)); + RF_UNLOCK_QUEUE(queue); + } + queue->numOutstanding--; + RF_ASSERT(queue->numOutstanding >= 0); + + /* dispatch requests to the disk until we find one that we can't. */ + /* no reason to continue once we've filled up the queue */ + /* no reason to even start if the queue is locked */ + + while (!done && !RF_QUEUE_FULL(queue) && !RF_QUEUE_LOCKED(queue)) { + if (queue->nextLockingOp) { + req = queue->nextLockingOp; + queue->nextLockingOp = NULL; + Dprintf3("DiskIOComplete: a pri %d locking req was pending at r %d c %d\n", req->priority, queue->row, queue->col); + } else { + req = (queue->qPtr->Dequeue) (queue->qHdr); + if (req != NULL) { + Dprintf3("DiskIOComplete: extracting pri %d req from queue at r %d c %d\n", req->priority, queue->row, queue->col); + } else { + Dprintf1("DiskIOComplete: no more requests to extract.\n", ""); + } + } + if (req) { + queue->queueLength--; /* decrement count of number + * of requests waiting in this + * queue */ + RF_ASSERT(queue->queueLength >= 0); + } + if (!req) + done = 1; + else + if (RF_LOCKING_REQ(req)) { + if (RF_QUEUE_EMPTY(queue)) { /* dispatch it */ + Dprintf3("DiskIOComplete: dispatching pri %d locking req to r %d c %d (queue empty)\n", req->priority, queue->row, queue->col); + RF_LOCK_QUEUE(queue); + rf_DispatchKernelIO(queue, req); + done = 1; + } else { /* put it aside to wait for + * the queue to drain */ + Dprintf3("DiskIOComplete: postponing pri %d locking req to r %d c %d\n", req->priority, queue->row, queue->col); + RF_ASSERT(queue->nextLockingOp == NULL); + queue->nextLockingOp = req; + done = 1; + } + } else + if (RF_UNLOCKING_REQ(req)) { /* should not happen: + * unlocking ops should + * not get queued */ + RF_ASSERT(RF_QUEUE_LOCKED(queue)); /* support it anyway for + * the future */ + Dprintf3("DiskIOComplete: dispatching pri %d unl req to r %d c %d (SHOULD NOT SEE THIS)\n", req->priority, queue->row, queue->col); + rf_DispatchKernelIO(queue, req); + done = 1; + } else + if (RF_OK_TO_DISPATCH(queue, req)) { + Dprintf3("DiskIOComplete: dispatching pri %d regular req to r %d c %d (ok to dispatch)\n", req->priority, queue->row, queue->col); + rf_DispatchKernelIO(queue, req); + } else { /* we can't dispatch it, + * so just re-enqueue + * it. */ + /* potential trouble here if + * disk queues batch reqs */ + Dprintf3("DiskIOComplete: re-enqueueing pri %d regular req to r %d c %d\n", req->priority, queue->row, queue->col); + queue->queueLength++; + (queue->qPtr->Enqueue) (queue->qHdr, req, req->priority); + done = 1; + } + } + + RF_UNLOCK_QUEUE_MUTEX(queue, "DiskIOComplete"); +} +/* promotes accesses tagged with the given parityStripeID from low priority + * to normal priority. This promotion is optional, meaning that a queue + * need not implement it. If there is no promotion routine associated with + * a queue, this routine does nothing and returns -1. + */ +int +rf_DiskIOPromote(queue, parityStripeID, which_ru) + RF_DiskQueue_t *queue; + RF_StripeNum_t parityStripeID; + RF_ReconUnitNum_t which_ru; +{ + int retval; + + if (!queue->qPtr->Promote) + return (-1); + RF_LOCK_QUEUE_MUTEX(queue, "DiskIOPromote"); + retval = (queue->qPtr->Promote) (queue->qHdr, parityStripeID, which_ru); + RF_UNLOCK_QUEUE_MUTEX(queue, "DiskIOPromote"); + return (retval); +} + +RF_DiskQueueData_t * +rf_CreateDiskQueueData( + RF_IoType_t typ, + RF_SectorNum_t ssect, + RF_SectorCount_t nsect, + caddr_t buf, + RF_StripeNum_t parityStripeID, + RF_ReconUnitNum_t which_ru, + int (*wakeF) (void *, int), + void *arg, + RF_DiskQueueData_t * next, + RF_AccTraceEntry_t * tracerec, + void *raidPtr, + RF_DiskQueueDataFlags_t flags, + void *kb_proc) +{ + RF_DiskQueueData_t *p; + + RF_FREELIST_GET_INIT(rf_dqd_freelist, p, next, (RF_DiskQueueData_t *), init_dqd); + + p->sectorOffset = ssect + rf_protectedSectors; + p->numSector = nsect; + p->type = typ; + p->buf = buf; + p->parityStripeID = parityStripeID; + p->which_ru = which_ru; + p->CompleteFunc = wakeF; + p->argument = arg; + p->next = next; + p->tracerec = tracerec; + p->priority = RF_IO_NORMAL_PRIORITY; + p->AuxFunc = NULL; + p->buf2 = NULL; + p->raidPtr = raidPtr; + p->flags = flags; + p->b_proc = kb_proc; + return (p); +} + +RF_DiskQueueData_t * +rf_CreateDiskQueueDataFull( + RF_IoType_t typ, + RF_SectorNum_t ssect, + RF_SectorCount_t nsect, + caddr_t buf, + RF_StripeNum_t parityStripeID, + RF_ReconUnitNum_t which_ru, + int (*wakeF) (void *, int), + void *arg, + RF_DiskQueueData_t * next, + RF_AccTraceEntry_t * tracerec, + int priority, + int (*AuxFunc) (void *,...), + caddr_t buf2, + void *raidPtr, + RF_DiskQueueDataFlags_t flags, + void *kb_proc) +{ + RF_DiskQueueData_t *p; + + RF_FREELIST_GET_INIT(rf_dqd_freelist, p, next, (RF_DiskQueueData_t *), init_dqd); + + p->sectorOffset = ssect + rf_protectedSectors; + p->numSector = nsect; + p->type = typ; + p->buf = buf; + p->parityStripeID = parityStripeID; + p->which_ru = which_ru; + p->CompleteFunc = wakeF; + p->argument = arg; + p->next = next; + p->tracerec = tracerec; + p->priority = priority; + p->AuxFunc = AuxFunc; + p->buf2 = buf2; + p->raidPtr = raidPtr; + p->flags = flags; + p->b_proc = kb_proc; + return (p); +} + +void +rf_FreeDiskQueueData(p) + RF_DiskQueueData_t *p; +{ + RF_FREELIST_FREE_CLEAN(rf_dqd_freelist, p, next, clean_dqd); +} |
