diff options
Diffstat (limited to 'lib/libgeom/geom_stats.c')
| -rw-r--r-- | lib/libgeom/geom_stats.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/lib/libgeom/geom_stats.c b/lib/libgeom/geom_stats.c new file mode 100644 index 000000000000..510636eb9a8b --- /dev/null +++ b/lib/libgeom/geom_stats.c @@ -0,0 +1,180 @@ +/*- + * SPDX-License-Identifier: BSD-3-Clause + * + * Copyright (c) 2003 Poul-Henning Kamp + * All rights reserved. + * + * 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. The names of the authors may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + */ + +#include <sys/types.h> +#include <sys/ioctl.h> +#include <sys/disk.h> +#include <sys/devicestat.h> +#include <sys/mman.h> +#include <sys/time.h> +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <paths.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <libgeom.h> + +/************************************************************/ +static uint npages, spp; +static int pagesize, statsfd = -1; +static u_char *statp; + +void +geom_stats_close(void) +{ + if (statsfd == -1) + return; + if (statp != NULL) { + if (munmap(statp, npages * pagesize) != 0) + err(1, "munmap"); + statp = NULL; + } + close(statsfd); + statsfd = -1; +} + +void +geom_stats_resync(void) +{ + void *p; + off_t mediasize; + int error; + + if (statsfd == -1) + return; + error = ioctl(statsfd, DIOCGMEDIASIZE, &mediasize); + if (error) + err(1, "DIOCGMEDIASIZE(" _PATH_DEV DEVSTAT_DEVICE_NAME ")"); + + if (statp != NULL && munmap(statp, npages * pagesize) != 0) + err(1, "munmap"); + p = mmap(NULL, mediasize, PROT_READ, MAP_SHARED, statsfd, 0); + if (p == MAP_FAILED) + err(1, "mmap(/dev/devstat)"); + statp = p; + npages = mediasize / pagesize; +} + +int +geom_stats_open(void) +{ + if (statsfd != -1) + return (EBUSY); + statsfd = open(_PATH_DEV DEVSTAT_DEVICE_NAME, O_RDONLY); + if (statsfd < 0) + return (errno); + pagesize = getpagesize(); + spp = pagesize / sizeof(struct devstat); + npages = 1; + geom_stats_resync(); + return (0); +} + +struct snapshot { + u_char *ptr; + uint pages; + uint pagesize; + uint perpage; + struct timespec time; + /* used by getnext: */ + uint u, v; +}; + +void * +geom_stats_snapshot_get(void) +{ + struct snapshot *sp; + + sp = malloc(sizeof *sp); + if (sp == NULL) + return (NULL); + memset(sp, 0, sizeof *sp); + sp->ptr = malloc(pagesize * npages); + if (sp->ptr == NULL) { + free(sp); + return (NULL); + } + explicit_bzero(sp->ptr, pagesize * npages); /* page in, cache */ + clock_gettime(CLOCK_REALTIME, &sp->time); + memcpy(sp->ptr, statp, pagesize * npages); + sp->pages = npages; + sp->perpage = spp; + sp->pagesize = pagesize; + return (sp); +} + +void +geom_stats_snapshot_free(void *arg) +{ + struct snapshot *sp; + + sp = arg; + free(sp->ptr); + free(sp); +} + +void +geom_stats_snapshot_timestamp(void *arg, struct timespec *tp) +{ + struct snapshot *sp; + + sp = arg; + *tp = sp->time; +} + +void +geom_stats_snapshot_reset(void *arg) +{ + struct snapshot *sp; + + sp = arg; + sp->u = sp->v = 0; +} + +struct devstat * +geom_stats_snapshot_next(void *arg) +{ + struct devstat *gsp; + struct snapshot *sp; + + sp = arg; + gsp = (struct devstat *) + (sp->ptr + sp->u * pagesize + sp->v * sizeof *gsp); + if (++sp->v >= sp->perpage) { + if (++sp->u >= sp->pages) + return (NULL); + else + sp->v = 0; + } + return (gsp); +} |