/* $NetBSD: subr_disk.c,v 1.26 2000/01/21 23:20:51 thorpej Exp $ */ /*- * Copyright (c) 1996, 1997, 1999, 2000 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, * NASA Ames Research Center. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. * All or some portions of this file are derived from material licensed * to the University of California by American Telephone and Telegraph * Co. or Unix System Laboratories, Inc. and are reproduced herein with * the permission of UNIX System Laboratories, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)ufs_disksubr.c 8.5 (Berkeley) 1/21/94 */ #include #include #include #include #include #include #include #include #include /* * A global list of all disks attached to the system. May grow or * shrink over time. */ struct disklist_head disklist; /* TAILQ_HEAD */ int disk_count; /* number of drives in global disklist */ /* * Seek sort for disks. We depend on the driver which calls us using b_resid * as the current cylinder number. * * The argument bufq is an I/O queue for the device, on which there are * actually two queues, sorted in ascending cylinder order. The first * queue holds those requests which are positioned after the current * cylinder (in the first request); the second holds requests which came * in after their cylinder number was passed. Thus we implement a one-way * scan, retracting after reaching the end of the drive to the first request * on the second queue, at which time it becomes the first queue. * * A one-way scan is natural because of the way UNIX read-ahead blocks are * allocated. * * This is further adjusted by any `barriers' which may exist in the queue. * The bufq points to the last such ordered request. */ void disksort_cylinder(bufq, bp) struct buf_queue *bufq; struct buf *bp; { struct buf *bq, *nbq; /* * If there are ordered requests on the queue, we must start * the elevator sort after the last of these. */ if ((bq = bufq->bq_barrier) == NULL) bq = BUFQ_FIRST(bufq); /* * If the queue is empty, of if it's an ordered request, * it's easy; we just go on the end. */ if (bq == NULL || (bp->b_flags & B_ORDERED) != 0) { BUFQ_INSERT_TAIL(bufq, bp); return; } /* * If we lie after the first (currently active) request, then we * must locate the second request list and add ourselves to it. */ if (bp->b_cylinder < bq->b_cylinder) { while ((nbq = BUFQ_NEXT(bq)) != NULL) { /* * Check for an ``inversion'' in the normally ascending * cylinder numbers, indicating the start of the second * request list. */ if (nbq->b_cylinder < bq->b_cylinder) { /* * Search the second request list for the first * request at a larger cylinder number. We go * before that; if there is no such request, we * go at end. */ do { if (bp->b_cylinder < nbq->b_cylinder) goto insert; if (bp->b_cylinder == nbq->b_cylinder && bp->b_blkno < nbq->b_blkno) goto insert; bq = nbq; } while ((nbq = BUFQ_NEXT(bq)) != NULL); goto insert; /* after last */ } bq = BUFQ_NEXT(bq); } /* * No inversions... we will go after the last, and * be the first request in the second request list. */ goto insert; } /* * Request is at/after the current request... * sort in the first request list. */ while ((nbq = BUFQ_NEXT(bq)) != NULL) { /* * We want to go after the current request if there is an * inversion after it (i.e. it is the end of the first * request list), or if the next request is a larger cylinder * than our request. */ if (nbq->b_cylinder < bq->b_cylinder || bp->b_cylinder < nbq->b_cylinder || (bp->b_cylinder == nbq->b_cylinder && bp->b_blkno < nbq->b_blkno)) goto insert; bq = nbq; } /* * Neither a second list nor a larger request... we go at the end of * the first list, which is the same as the end of the whole schebang. */ insert: BUFQ_INSERT_AFTER(bufq, bq, bp); } /* * Seek sort for disks. This version sorts based on b_blkno, which * indicates the block number. * * As before, there are actually two queues, sorted in ascendening block * order. The first queue holds those requests which are positioned after * the current block (in the first request); the second holds requests which * came in after their block number was passed. Thus we implement a one-way * scan, retracting after reaching the end of the driver to the first request * on the second queue, at which time it becomes the first queue. * * A one-way scan is natural because of the way UNIX read-ahead blocks are * allocated. * * This is further adjusted by any `barriers' which may exist in the queue. * The bufq points to the last such ordered request. */ void disksort_blkno(bufq, bp) struct buf_queue *bufq; struct buf *bp; { struct buf *bq, *nbq; /* * If there are ordered requests on the queue, we must start * the elevator sort after the last of these. */ if ((bq = bufq->bq_barrier) == NULL) bq = BUFQ_FIRST(bufq); /* * If the queue is empty, or if it's an ordered request, * it's easy; we just go on the end. */ if (bq == NULL || (bp->b_flags & B_ORDERED) != 0) { BUFQ_INSERT_TAIL(bufq, bp); return; } /* * If we lie after the first (currently active) request, then we * must locate the second request list and add ourselves to it. */ if (bp->b_blkno < bq->b_blkno) { while ((nbq = BUFQ_NEXT(bq)) != NULL) { /* * Check for an ``inversion'' in the normally ascending * block numbers, indicating the start of the second * request list. */ if (nbq->b_blkno < bq->b_blkno) { /* * Search the second request list for the first * request at a larger block number. We go * after that; if there is no such request, we * go at the end. */ do { if (bp->b_blkno < nbq->b_blkno) goto insert; bq = nbq; } while ((nbq = BUFQ_NEXT(bq)) != NULL); goto insert; /* after last */ } bq = BUFQ_NEXT(bq); } /* * No inversions... we will go after the last, and * be the first request in the second request list. */ goto insert; } /* * Request is at/after the current request... * sort in the first request list. */ while ((nbq = BUFQ_NEXT(bq)) != NULL) { /* * We want to go after the current request if there is an * inversion after it (i.e. it is the end of the first * request list), or if the next request is a larger cylinder * than our request. */ if (nbq->b_blkno < bq->b_blkno || bp->b_blkno < nbq->b_blkno) goto insert; bq = nbq; } /* * Neither a second list nor a larger request... we go at the end of * the first list, which is the same as the end of the whole schebang. */ insert: BUFQ_INSERT_AFTER(bufq, bq, bp); } /* * Seek non-sort for disks. This version simply inserts requests at * the tail of the queue. */ void disksort_tail(bufq, bp) struct buf_queue *bufq; struct buf *bp; { BUFQ_INSERT_TAIL(bufq, bp); } /* * Compute checksum for disk label. */ u_int dkcksum(lp) register struct disklabel *lp; { register u_short *start, *end; register u_short sum = 0; start = (u_short *)lp; end = (u_short *)&lp->d_partitions[lp->d_npartitions]; while (start < end) sum ^= *start++; return (sum); } /* * Disk error is the preface to plaintive error messages * about failing disk transfers. It prints messages of the form hp0g: hard error reading fsbn 12345 of 12344-12347 (hp0 bn %d cn %d tn %d sn %d) * if the offset of the error in the transfer and a disk label * are both available. blkdone should be -1 if the position of the error * is unknown; the disklabel pointer may be null from drivers that have not * been converted to use them. The message is printed with printf * if pri is LOG_PRINTF, otherwise it uses log at the specified priority. * The message should be completed (with at least a newline) with printf * or addlog, respectively. There is no trailing space. */ void diskerr(bp, dname, what, pri, blkdone, lp) register struct buf *bp; char *dname, *what; int pri, blkdone; register struct disklabel *lp; { int unit = DISKUNIT(bp->b_dev), part = DISKPART(bp->b_dev); register void (*pr) __P((const char *, ...)); char partname = 'a' + part; int sn; if (pri != LOG_PRINTF) { static const char fmt[] = ""; log(pri, fmt); pr = addlog; } else pr = printf; (*pr)("%s%d%c: %s %sing fsbn ", dname, unit, partname, what, bp->b_flags & B_READ ? "read" : "writ"); sn = bp->b_blkno; if (bp->b_bcount <= DEV_BSIZE) (*pr)("%d", sn); else { if (blkdone >= 0) { sn += blkdone; (*pr)("%d of ", sn); } (*pr)("%d-%d", bp->b_blkno, bp->b_blkno + (bp->b_bcount - 1) / DEV_BSIZE); } if (lp && (blkdone >= 0 || bp->b_bcount <= lp->d_secsize)) { sn += lp->d_partitions[part].p_offset; (*pr)(" (%s%d bn %d; cn %d", dname, unit, sn, sn / lp->d_secpercyl); sn %= lp->d_secpercyl; (*pr)(" tn %d sn %d)", sn / lp->d_nsectors, sn % lp->d_nsectors); } } /* * Initialize the disklist. Called by main() before autoconfiguration. */ void disk_init() { TAILQ_INIT(&disklist); disk_count = 0; } /* * Searches the disklist for the disk corresponding to the * name provided. */ struct disk * disk_find(name) char *name; { struct disk *diskp; if ((name == NULL) || (disk_count <= 0)) return (NULL); for (diskp = disklist.tqh_first; diskp != NULL; diskp = diskp->dk_link.tqe_next) if (strcmp(diskp->dk_name, name) == 0) return (diskp); return (NULL); } /* * Attach a disk. */ void disk_attach(diskp) struct disk *diskp; { int s; /* * Allocate and initialize the disklabel structures. Note that * it's not safe to sleep here, since we're probably going to be * called during autoconfiguration. */ diskp->dk_label = malloc(sizeof(struct disklabel), M_DEVBUF, M_NOWAIT); diskp->dk_cpulabel = malloc(sizeof(struct cpu_disklabel), M_DEVBUF, M_NOWAIT); if ((diskp->dk_label == NULL) || (diskp->dk_cpulabel == NULL)) panic("disk_attach: can't allocate storage for disklabel"); memset(diskp->dk_label, 0, sizeof(struct disklabel)); memset(diskp->dk_cpulabel, 0, sizeof(struct cpu_disklabel)); /* * Set the attached timestamp. */ s = splclock(); diskp->dk_attachtime = mono_time; splx(s); /* * Link into the disklist. */ TAILQ_INSERT_TAIL(&disklist, diskp, dk_link); ++disk_count; } /* * Detach a disk. */ void disk_detach(diskp) struct disk *diskp; { /* * Remove from the disklist. */ if (--disk_count < 0) panic("disk_detach: disk_count < 0"); TAILQ_REMOVE(&disklist, diskp, dk_link); /* * Free the space used by the disklabel structures. */ free(diskp->dk_label, M_DEVBUF); free(diskp->dk_cpulabel, M_DEVBUF); } /* * Increment a disk's busy counter. If the counter is going from * 0 to 1, set the timestamp. */ void disk_busy(diskp) struct disk *diskp; { int s; /* * XXX We'd like to use something as accurate as microtime(), * but that doesn't depend on the system TOD clock. */ if (diskp->dk_busy++ == 0) { s = splclock(); diskp->dk_timestamp = mono_time; splx(s); } } /* * Decrement a disk's busy counter, increment the byte count, total busy * time, and reset the timestamp. */ void disk_unbusy(diskp, bcount) struct disk *diskp; long bcount; { int s; struct timeval dv_time, diff_time; if (diskp->dk_busy-- == 0) { printf("%s: dk_busy < 0\n", diskp->dk_name); panic("disk_unbusy"); } s = splclock(); dv_time = mono_time; splx(s); timersub(&dv_time, &diskp->dk_timestamp, &diff_time); timeradd(&diskp->dk_time, &diff_time, &diskp->dk_time); diskp->dk_timestamp = dv_time; if (bcount > 0) { diskp->dk_bytes += bcount; diskp->dk_xfer++; } } /* * Reset the metrics counters on the given disk. Note that we cannot * reset the busy counter, as it may case a panic in disk_unbusy(). * We also must avoid playing with the timestamp information, as it * may skew any pending transfer results. */ void disk_resetstat(diskp) struct disk *diskp; { int s = splbio(), t; diskp->dk_xfer = 0; diskp->dk_bytes = 0; t = splclock(); diskp->dk_attachtime = mono_time; splx(t); timerclear(&diskp->dk_time); splx(s); }