From: Darrick J. Wong <djwong@xxxxxxxxxx>
Create a subcommand to monitor for health events generated by the kernel.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
io/Makefile | 1
io/healthmon.c | 172 +++++++++++++++++++++++++++++++++++++++++++++++++++++
io/init.c | 1
io/io.h | 1
man/man8/xfs_io.8 | 22 +++++++
5 files changed, 197 insertions(+)
create mode 100644 io/healthmon.c
diff --git a/io/Makefile b/io/Makefile
index 787027fe10ed..b1f9cebd63b0 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -24,6 +24,7 @@ CFILES = \
fsuuid.c \
fsync.c \
getrusage.c \
+ healthmon.c \
imap.c \
inject.c \
label.c \
diff --git a/io/healthmon.c b/io/healthmon.c
new file mode 100644
index 000000000000..7db8c52c96c0
--- /dev/null
+++ b/io/healthmon.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 Oracle. All Rights Reserved.
+ * Author: Darrick J. Wong <djwong@xxxxxxxxxx>
+ */
+#include "libxfs.h"
+#include "libfrog/fsgeom.h"
+#include "libfrog/paths.h"
+#include "command.h"
+#include "init.h"
+#include "io.h"
+
+static void
+healthmon_help(void)
+{
+ printf(_(
+"Monitor filesystem health events"
+"\n"
+"-c Replace the open file with the monitor file.\n"
+"-d delay_ms Sleep this many milliseconds between reads.\n"
+"-p Only probe for the existence of the ioctl.\n"
+"-v Request all events.\n"
+"\n"));
+}
+
+static inline int
+monitor_sleep(
+ int delay_ms)
+{
+ struct timespec ts;
+
+ if (!delay_ms)
+ return 0;
+
+ ts.tv_sec = delay_ms / 1000;
+ ts.tv_nsec = (delay_ms % 1000) * 1000000;
+
+ return nanosleep(&ts, NULL);
+}
+
+#define BUFSIZE (4096)
+
+static int
+monitor(
+ bool consume,
+ int delay_ms,
+ bool verbose,
+ bool only_probe)
+{
+ struct xfs_health_monitor hmo = {
+ .format = XFS_HEALTH_MONITOR_FMT_JSON,
+ };
+ char *buf;
+ ssize_t bytes_read;
+ int mon_fd;
+ int ret = 1;
+
+ if (verbose)
+ hmo.flags |= XFS_HEALTH_MONITOR_ALL;
+
+ mon_fd = ioctl(file->fd, XFS_IOC_HEALTH_MONITOR, &hmo);
+ if (mon_fd < 0) {
+ perror("XFS_IOC_HEALTH_MONITOR");
+ return 1;
+ }
+
+ if (only_probe) {
+ ret = 0;
+ goto out_mon;
+ }
+
+ buf = malloc(BUFSIZE);
+ if (!buf) {
+ perror("malloc");
+ goto out_mon;
+ }
+
+ if (consume) {
+ close(file->fd);
+ file->fd = mon_fd;
+ }
+
+ monitor_sleep(delay_ms);
+ while ((bytes_read = read(mon_fd, buf, BUFSIZE)) > 0) {
+ char *write_ptr = buf;
+ ssize_t bytes_written;
+ size_t to_write = bytes_read;
+
+ while ((bytes_written = write(STDOUT_FILENO, write_ptr, to_write)) > 0) {
+ write_ptr += bytes_written;
+ to_write -= bytes_written;
+ }
+ if (bytes_written < 0) {
+ perror("healthdump");
+ goto out_buf;
+ }
+
+ monitor_sleep(delay_ms);
+ }
+ if (bytes_read < 0) {
+ perror("healthmon");
+ goto out_buf;
+ }
+
+ ret = 0;
+
+out_buf:
+ free(buf);
+out_mon:
+ close(mon_fd);
+ return ret;
+}
+
+static int
+healthmon_f(
+ int argc,
+ char **argv)
+{
+ bool consume = false;
+ bool verbose = false;
+ bool only_probe = false;
+ int delay_ms = 0;
+ int c;
+
+ while ((c = getopt(argc, argv, "cd:pv")) != EOF) {
+ switch (c) {
+ case 'c':
+ consume = true;
+ break;
+ case 'd':
+ errno = 0;
+ delay_ms = atoi(optarg);
+ if (delay_ms < 0 || errno) {
+ printf("%s: delay must be positive msecs\n",
+ optarg);
+ exitcode = 1;
+ return 0;
+ }
+ break;
+ case 'p':
+ only_probe = true;
+ break;
+ case 'v':
+ verbose = true;
+ break;
+ default:
+ exitcode = 1;
+ healthmon_help();
+ return 0;
+ }
+ }
+
+ return monitor(consume, delay_ms, verbose, only_probe);
+}
+
+static struct cmdinfo healthmon_cmd = {
+ .name = "healthmon",
+ .cfunc = healthmon_f,
+ .argmin = 0,
+ .argmax = -1,
+ .flags = CMD_FLAG_ONESHOT | CMD_NOMAP_OK,
+ .args = "[-c] [-d delay_ms] [-v]",
+ .help = healthmon_help,
+};
+
+void
+healthmon_init(void)
+{
+ healthmon_cmd.oneline = _("monitor filesystem health events");
+
+ add_command(&healthmon_cmd);
+}
diff --git a/io/init.c b/io/init.c
index 452f4cfc898c..ef32e74bc744 100644
--- a/io/init.c
+++ b/io/init.c
@@ -91,6 +91,7 @@ init_commands(void)
utimes_init();
crc32cselftest_init();
exchrange_init();
+ healthmon_init();
}
/*
diff --git a/io/io.h b/io/io.h
index 06a8ae1db496..b8bed3b66171 100644
--- a/io/io.h
+++ b/io/io.h
@@ -192,3 +192,4 @@ extern void bulkstat_init(void);
extern void exchrange_init(void);
extern void aginfo_init(void);
extern void fsrefcounts_init(void);
+extern void healthmon_init(void);
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 93a4f0790d8e..9f00d26a0b49 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -1407,6 +1407,28 @@ flag.
.RE
.PD
+.TP
+.BI "healthmon [ \-c ] [ \-d " delay_ms " ] [ \-p ] [ \-v ]"
+Watch for filesystem health events and write them to the console.
+.RE
+.RS 1.0i
+.PD 0
+.TP
+.BI \-c
+Close the open file and replace it with the monitor file.
+.TP
+.BI "\-d " delay_ms
+Sleep for this long between read attempts.
+.TP
+.B \-p
+Probe for the existence of the functionality by opening the monitoring fd and
+closing it immediately.
+.TP
+.BI \-v
+Request all health events, even if nothing changed.
+.PD
+.RE
+
.TP
.BI "inject [ " tag " ]"
Inject errors into a filesystem to observe filesystem behavior at
