diff options
Diffstat (limited to 'sys/kern/subr_disk.c')
| -rw-r--r-- | sys/kern/subr_disk.c | 184 |
1 files changed, 181 insertions, 3 deletions
diff --git a/sys/kern/subr_disk.c b/sys/kern/subr_disk.c index f3615211358..8ec8d7d9d10 100644 --- a/sys/kern/subr_disk.c +++ b/sys/kern/subr_disk.c @@ -1,6 +1,7 @@ -/* $NetBSD: subr_disk.c,v 1.14 1995/12/28 19:16:39 thorpej Exp $ */ +/* $NetBSD: subr_disk.c,v 1.15 1996/01/07 22:03:49 thorpej Exp $ */ /* + * Copyright (c) 1995 Jason R. Thorpe. All rights reserved. * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. All rights reserved. * (c) UNIX System Laboratories, Inc. @@ -42,12 +43,23 @@ #include <sys/param.h> #include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/malloc.h> #include <sys/buf.h> -#include <sys/disklabel.h> #include <sys/syslog.h> +#include <sys/time.h> +#include <sys/disklabel.h> +#include <sys/disk.h> #include <sys/dkstat.h> /* XXX */ /* + * 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 */ + +/* * Old-style disk instrumentation structures. These will go away * someday. */ @@ -57,7 +69,7 @@ long dk_wds[DK_NDRIVE]; long dk_wpms[DK_NDRIVE]; long dk_xfer[DK_NDRIVE]; int dk_busy; -int dk_ndrive = DK_NDRIVE; +int dk_ndrive; int dkn; /* number of slots filled so far */ /* @@ -231,3 +243,169 @@ diskerr(bp, dname, what, pri, blkdone, lp) (*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; + dk_ndrive = DK_NDRIVE; /* XXX */ +} + +/* + * 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"); + + bzero(diskp->dk_label, sizeof(struct disklabel)); + bzero(diskp->dk_cpulabel, 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; +} + +/* + * Detatch a disk. + */ +void +disk_detatch(diskp) + struct disk *diskp; +{ + + /* + * Free the space used by the disklabel structures. + */ + free(diskp->dk_label, M_DEVBUF); + free(diskp->dk_cpulabel, M_DEVBUF); + + /* + * Remove from the disklist. + */ + TAILQ_REMOVE(&disklist, diskp, dk_link); + if (--disk_count < 0) + panic("disk_detatch: disk_count < 0"); +} + +/* + * 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) + panic("disk_unbusy: %s: dk_busy < 0", diskp->dk_name); + + 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); +} |