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-rw-r--r--lib/libkvm/kvm_getswapinfo.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/lib/libkvm/kvm_getswapinfo.c b/lib/libkvm/kvm_getswapinfo.c
new file mode 100644
index 0000000..bc9d293
--- /dev/null
+++ b/lib/libkvm/kvm_getswapinfo.c
@@ -0,0 +1,277 @@
+/*
+ * Copyright (c) 1999, Matthew Dillon. All Rights Reserved.
+ * Copyright (c) 2001, Thomas Moestl. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY 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 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/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <sys/blist.h>
+#include <sys/sysctl.h>
+
+#include <vm/swap_pager.h>
+#include <vm/vm_param.h>
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <kvm.h>
+#include <nlist.h>
+#include <paths.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+
+#include "kvm_private.h"
+
+static struct nlist kvm_swap_nl[] = {
+ { "_swtailq" }, /* list of swap devices and sizes */
+ { "_dmmax" }, /* maximum size of a swap block */
+ { NULL }
+};
+
+#define NL_SWTAILQ 0
+#define NL_DMMAX 1
+
+static int kvm_swap_nl_cached = 0;
+static int unswdev; /* number of found swap dev's */
+static int dmmax;
+
+static int kvm_getswapinfo_kvm(kvm_t *, struct kvm_swap *, int, int);
+static int kvm_getswapinfo_sysctl(kvm_t *, struct kvm_swap *, int, int);
+static int nlist_init(kvm_t *);
+static int getsysctl(kvm_t *, char *, void *, size_t);
+
+#define KREAD(kd, addr, obj) \
+ (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj))
+#define KGET(idx, var) \
+ KGET2(kvm_swap_nl[(idx)].n_value, var, kvm_swap_nl[(idx)].n_name)
+#define KGET2(addr, var, msg) \
+ if (KREAD(kd, (u_long)(addr), (var))) { \
+ _kvm_err(kd, kd->program, "cannot read %s", msg); \
+ return (-1); \
+ }
+
+#define GETSWDEVNAME(dev, str, flags) \
+ if (dev == NODEV) { \
+ strlcpy(str, "[NFS swap]", sizeof(str)); \
+ } else { \
+ snprintf( \
+ str, sizeof(str),"%s%s", \
+ ((flags & SWIF_DEV_PREFIX) ? _PATH_DEV : ""), \
+ devname(dev, S_IFCHR) \
+ ); \
+ }
+
+int
+kvm_getswapinfo(
+ kvm_t *kd,
+ struct kvm_swap *swap_ary,
+ int swap_max,
+ int flags
+) {
+
+ /*
+ * clear cache
+ */
+ if (kd == NULL) {
+ kvm_swap_nl_cached = 0;
+ return(0);
+ }
+
+ if (ISALIVE(kd)) {
+ return kvm_getswapinfo_sysctl(kd, swap_ary, swap_max, flags);
+ } else {
+ return kvm_getswapinfo_kvm(kd, swap_ary, swap_max, flags);
+ }
+}
+
+int
+kvm_getswapinfo_kvm(
+ kvm_t *kd,
+ struct kvm_swap *swap_ary,
+ int swap_max,
+ int flags
+) {
+ int i, ttl;
+ TAILQ_HEAD(, swdevt) swtailq;
+ struct swdevt *sp, swinfo;
+ struct kvm_swap tot;
+
+ if (!nlist_init(kd))
+ return (-1);
+
+ bzero(&tot, sizeof(tot));
+ KGET(NL_SWTAILQ, &swtailq);
+ sp = TAILQ_FIRST(&swtailq);
+ for (i = 0; sp != NULL; i++) {
+ KGET2(sp, &swinfo, "swinfo");
+ ttl = swinfo.sw_nblks - dmmax;
+ if (i < swap_max - 1) {
+ bzero(&swap_ary[i], sizeof(swap_ary[i]));
+ swap_ary[i].ksw_total = ttl;
+ swap_ary[i].ksw_used = swinfo.sw_used;
+ swap_ary[i].ksw_flags = swinfo.sw_flags;
+ GETSWDEVNAME(swinfo.sw_dev, swap_ary[i].ksw_devname,
+ flags);
+ }
+ tot.ksw_total += ttl;
+ tot.ksw_used += swinfo.sw_used;
+ sp = TAILQ_NEXT(&swinfo, sw_list);
+ }
+
+ if (i >= swap_max)
+ i = swap_max - 1;
+ if (i >= 0)
+ swap_ary[i] = tot;
+
+ return(i);
+}
+
+#define GETSYSCTL(kd, name, var) \
+ getsysctl(kd, name, &(var), sizeof(var))
+
+/* The maximum MIB length for vm.swap_info and an additional device number */
+#define SWI_MAXMIB 3
+
+int
+kvm_getswapinfo_sysctl(
+ kvm_t *kd,
+ struct kvm_swap *swap_ary,
+ int swap_max,
+ int flags
+) {
+ int ti, ttl;
+ size_t mibi, len;
+ int soid[SWI_MAXMIB];
+ struct xswdev xsd;
+ struct kvm_swap tot;
+
+ if (!GETSYSCTL(kd, "vm.dmmax", dmmax))
+ return -1;
+
+ mibi = SWI_MAXMIB - 1;
+ if (sysctlnametomib("vm.swap_info", soid, &mibi) == -1) {
+ _kvm_err(kd, kd->program, "sysctlnametomib failed: %s",
+ strerror(errno));
+ return -1;
+ }
+ bzero(&tot, sizeof(tot));
+ for (unswdev = 0;; unswdev++) {
+ soid[mibi] = unswdev;
+ len = sizeof(xsd);
+ if (sysctl(soid, mibi + 1, &xsd, &len, NULL, 0) == -1) {
+ if (errno == ENOENT)
+ break;
+ _kvm_err(kd, kd->program, "cannot read sysctl: %s.",
+ strerror(errno));
+ return -1;
+ }
+ if (len != sizeof(xsd)) {
+ _kvm_err(kd, kd->program, "struct xswdev has unexpected "
+ "size; kernel and libkvm out of sync?");
+ return -1;
+ }
+ if (xsd.xsw_version != XSWDEV_VERSION) {
+ _kvm_err(kd, kd->program, "struct xswdev version "
+ "mismatch; kernel and libkvm out of sync?");
+ return -1;
+ }
+
+ ttl = xsd.xsw_nblks - dmmax;
+ if (unswdev < swap_max - 1) {
+ bzero(&swap_ary[unswdev], sizeof(swap_ary[unswdev]));
+ swap_ary[unswdev].ksw_total = ttl;
+ swap_ary[unswdev].ksw_used = xsd.xsw_used;
+ swap_ary[unswdev].ksw_flags = xsd.xsw_flags;
+ GETSWDEVNAME(xsd.xsw_dev, swap_ary[unswdev].ksw_devname,
+ flags);
+ }
+ tot.ksw_total += ttl;
+ tot.ksw_used += xsd.xsw_used;
+ }
+
+ ti = unswdev;
+ if (ti >= swap_max)
+ ti = swap_max - 1;
+ if (ti >= 0)
+ swap_ary[ti] = tot;
+
+ return(ti);
+}
+
+static int
+nlist_init(kvm_t *kd)
+{
+ TAILQ_HEAD(, swdevt) swtailq;
+ struct swdevt *sp, swinfo;
+
+ if (kvm_swap_nl_cached)
+ return (1);
+
+ if (kvm_nlist(kd, kvm_swap_nl) < 0)
+ return (0);
+
+ /* Required entries */
+ if (kvm_swap_nl[NL_SWTAILQ].n_value == 0) {
+ _kvm_err(kd, kd->program, "unable to find swtailq");
+ return (0);
+ }
+
+ if (kvm_swap_nl[NL_DMMAX].n_value == 0) {
+ _kvm_err(kd, kd->program, "unable to find dmmax");
+ return (0);
+ }
+
+ /* Get globals, type of swap */
+ KGET(NL_DMMAX, &dmmax);
+
+ kvm_swap_nl_cached = 1;
+ return (1);
+}
+
+static int
+getsysctl (
+ kvm_t *kd,
+ char *name,
+ void *ptr,
+ size_t len
+) {
+ size_t nlen = len;
+ if (sysctlbyname(name, ptr, &nlen, NULL, 0) == -1) {
+ _kvm_err(kd, kd->program, "cannot read sysctl %s:%s", name,
+ strerror(errno));
+ return (0);
+ }
+ if (nlen != len) {
+ _kvm_err(kd, kd->program, "sysctl %s has unexpected size", name);
+ return (0);
+ }
+ return (1);
+}
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