Merging upstream version 4.2+20231121.

Signed-off-by: Daniel Baumann <daniel@debian.org>

Create.c

@@ -23,6 +23,7 @@
  */
 
 #include	"mdadm.h"
+#include	"udev.h"
 #include	"md_u.h"
 #include	"md_p.h"
 #include	<ctype.h>

Makefile

@@ -163,14 +163,14 @@ else
 	ECHO=:
 endif
 
-OBJS =  mdadm.o config.o policy.o mdstat.o  ReadMe.o uuid.o util.o maps.o lib.o \
+OBJS = mdadm.o config.o policy.o mdstat.o  ReadMe.o uuid.o util.o maps.o lib.o udev.o \
-	Manage.o Assemble.o Build.o \
+       Manage.o Assemble.o Build.o \
-	Create.o Detail.o Examine.o Grow.o Monitor.o dlink.o Kill.o Query.o \
+       Create.o Detail.o Examine.o Grow.o Monitor.o dlink.o Kill.o Query.o \
-	Incremental.o Dump.o \
+       Incremental.o Dump.o \
-	mdopen.o super0.o super1.o super-ddf.o super-intel.o bitmap.o \
+       mdopen.o super0.o super1.o super-ddf.o super-intel.o bitmap.o \
-	super-mbr.o super-gpt.o \
+       super-mbr.o super-gpt.o \
-	restripe.o sysfs.o sha1.o mapfile.o crc32.o sg_io.o msg.o xmalloc.o \
+       restripe.o sysfs.o sha1.o mapfile.o crc32.o sg_io.o msg.o xmalloc.o \
-	platform-intel.o probe_roms.o crc32c.o
+       platform-intel.o probe_roms.o crc32c.o
 
 CHECK_OBJS = restripe.o uuid.o sysfs.o maps.o lib.o xmalloc.o dlink.o
 
@@ -179,7 +179,7 @@ SRCS =  $(patsubst %.o,%.c,$(OBJS))
 INCL = mdadm.h part.h bitmap.h
 
 MON_OBJS = mdmon.o monitor.o managemon.o uuid.o util.o maps.o mdstat.o sysfs.o config.o mapfile.o mdopen.o\
-	policy.o lib.o \
+	policy.o lib.o udev.o \
 	Kill.o sg_io.o dlink.o ReadMe.o super-intel.o \
 	super-mbr.o super-gpt.o \
 	super-ddf.o sha1.o crc32.o msg.o bitmap.o xmalloc.o \

Manage.c

@@ -25,6 +25,7 @@
 #include "mdadm.h"
 #include "md_u.h"
 #include "md_p.h"
+#include "udev.h"
 #include <ctype.h>
 
 int Manage_ro(char *devname, int fd, int readonly)
@@ -462,7 +463,7 @@ done:
 		goto out;
 	}
 
-	if (devnm[0] && use_udev()) {
+	if (devnm[0] && udev_is_available()) {
 		struct map_ent *mp = map_by_devnm(&map, devnm);
 		remove_devices(devnm, mp ? mp->path : NULL);
 	}

Monitor.c

@@ -23,18 +23,17 @@
  */
 
 #include	"mdadm.h"
+#include	"udev.h"
 #include	"md_p.h"
 #include	"md_u.h"
 #include	<sys/wait.h>
 #include	<limits.h>
 #include	<syslog.h>
-#ifndef NO_LIBUDEV
-#include	<libudev.h>
-#endif
 
 #define TASK_COMM_LEN 16
 #define EVENT_NAME_MAX 32
 #define AUTOREBUILD_PID_PATH MDMON_DIR "/autorebuild.pid"
+#define FALLBACK_DELAY 5
 
 /**
  * struct state - external array or container properties.
@@ -126,12 +125,11 @@ static void link_containers_with_subarrays(struct state *list);
 static void free_statelist(struct state *statelist);
 static int check_array(struct state *st, struct mdstat_ent *mdstat, int increments, char *prefer);
 static int check_one_sharer(int scan);
-#ifndef NO_LIBUDEV
-static int check_udev_activity(void);
-#endif
 static void link_containers_with_subarrays(struct state *list);
 static int make_daemon(char *pidfile);
 static void try_spare_migration(struct state *statelist);
+static void wait_for_events(int *delay_for_event, int c_delay);
+static void wait_for_events_mdstat(int *delay_for_event, int c_delay);
 static int write_autorebuild_pid(void);
 
 int Monitor(struct mddev_dev *devlist,
@@ -326,32 +324,12 @@ int Monitor(struct mddev_dev *devlist,
 		if (!new_found) {
 			if (oneshot)
 				break;
-			else if (!anyredundant) {
+			if (!anyredundant) {
 				pr_err("No array with redundancy detected, stopping\n");
 				break;
 			}
-			else {
+
-#ifndef NO_LIBUDEV
+			wait_for_events(&delay_for_event, c->delay);
-				/*
-				 * Wait for udevd to finish new devices
-				 * processing.
-				 */
-				if (mdstat_wait(delay_for_event) &&
-				    check_udev_activity())
-					pr_err("Error while waiting for UDEV to complete new devices processing\n");
-#else
-				int wait_result = mdstat_wait(delay_for_event);
-				/*
-				 * Give chance to process new device
-				 */
-				if (wait_result != 0) {
-					if (c->delay > 5)
-						delay_for_event = 5;
-				} else
-					delay_for_event = c->delay;
-#endif
-				mdstat_close();
-			}
 		}
 		info.test = 0;
 
@@ -374,6 +352,49 @@ int Monitor(struct mddev_dev *devlist,
 	return 0;
 }
 
+/*
+ * wait_for_events() - Waits for events on md devices.
+ * @delay_for_event: pointer to current event delay
+ * @c_delay: delay from config
+ */
+static void wait_for_events(int *delay_for_event, int c_delay)
+{
+#ifndef NO_LIBUDEV
+	if (udev_is_available()) {
+		if (udev_wait_for_events(*delay_for_event) == UDEV_STATUS_ERROR)
+			pr_err("Error while waiting for udev events.\n");
+		return;
+	}
+#endif
+	wait_for_events_mdstat(delay_for_event, c_delay);
+}
+
+/*
+ * wait_for_events_mdstat() - Waits for events on mdstat.
+ * @delay_for_event: pointer to current event delay
+ * @c_delay: delay from config
+ */
+static void wait_for_events_mdstat(int *delay_for_event, int c_delay)
+{
+	int wait_result = mdstat_wait(*delay_for_event);
+
+	if (wait_result < 0) {
+		pr_err("Error while waiting for events on mdstat.\n");
+		return;
+	}
+
+	/*
+	 * Give chance to process new device
+	 */
+	if (wait_result != 0) {
+		if (c_delay > FALLBACK_DELAY)
+			*delay_for_event = FALLBACK_DELAY;
+	} else {
+		*delay_for_event = c_delay;
+	}
+	mdstat_close();
+}
+
 static int make_daemon(char *pidfile)
 {
 	/* Return:
@@ -1254,64 +1275,6 @@ static void free_statelist(struct state *statelist)
 	}
 }
 
-#ifndef NO_LIBUDEV
-/* function: check_udev_activity
- * Description: Function waits for udev to finish
- * events processing.
- * Returns:
- *		1 - detected error while opening udev
- *		2 - timeout
- *		0 - successfull completion
- */
-static int check_udev_activity(void)
-{
-	struct udev *udev = NULL;
-	struct udev_queue *udev_queue = NULL;
-	int timeout_cnt = 30;
-	int rc = 0;
-
-	/*
-	 * In rare cases systemd may not have udevm,
-	 * in such cases just exit with rc 0
-	 */
-	if (!use_udev())
-		goto out;
-
-	udev = udev_new();
-	if (!udev) {
-		rc = 1;
-		goto out;
-	}
-
-	udev_queue = udev_queue_new(udev);
-	if (!udev_queue) {
-		rc = 1;
-		goto out;
-	}
-
-	if (udev_queue_get_queue_is_empty(udev_queue))
-		goto out;
-
-	while (!udev_queue_get_queue_is_empty(udev_queue)) {
-		sleep(1);
-
-		if (timeout_cnt)
-			timeout_cnt--;
-		else {
-			rc = 2;
-			goto out;
-		}
-	}
-
-out:
-	if (udev_queue)
-		udev_queue_unref(udev_queue);
-	if (udev)
-		udev_unref(udev);
-	return rc;
-}
-#endif
-
 /* Not really Monitor but ... */
 int Wait(char *dev)
 {

lib.c

@@ -204,35 +204,6 @@ char *fd2devnm(int fd)
 	return NULL;
 }
 
-/* When we create a new array, we don't want the content to
- * be immediately examined by udev - it is probably meaningless.
- * So create /run/mdadm/creating-mdXXX and expect that a udev
- * rule will noticed this and act accordingly.
- */
-static char block_path[] = "/run/mdadm/creating-%s";
-static char *unblock_path = NULL;
-void udev_block(char *devnm)
-{
-	int fd;
-	char *path = NULL;
-
-	xasprintf(&path, block_path, devnm);
-	fd = open(path, O_CREAT|O_RDWR, 0600);
-	if (fd >= 0) {
-		close(fd);
-		unblock_path = path;
-	} else
-		free(path);
-}
-
-void udev_unblock(void)
-{
-	if (unblock_path)
-		unlink(unblock_path);
-	free(unblock_path);
-	unblock_path = NULL;
-}
-
 /*
  * convert a major/minor pair for a block device into a name in /dev, if possible.
  * On the first call, walk /dev collecting name.
@@ -539,19 +510,6 @@ int check_env(char *name)
 	return 0;
 }
 
-int use_udev(void)
-{
-	static int use = -1;
-	struct stat stb;
-
-	if (use < 0) {
-		use = ((stat("/dev/.udev", &stb) == 0 ||
-			stat("/run/udev", &stb) == 0) &&
-		       check_env("MDADM_NO_UDEV") == 0);
-	}
-	return use;
-}
-
 unsigned long GCD(unsigned long a, unsigned long b)
 {
 	while (a != b) {

mdadm.h

@@ -1656,6 +1656,7 @@ extern char *conf_line(FILE *file);
 extern char *conf_word(FILE *file, int allow_key);
 extern void print_quoted(char *str);
 extern int use_udev(void);
+extern void print_escape(char *str);
 extern unsigned long GCD(unsigned long a, unsigned long b);
 extern int conf_name_is_free(char *name);
 extern bool is_devname_ignore(const char *devname);
@@ -1764,8 +1765,6 @@ extern char *fd2kname(int fd);
 extern char *stat2devnm(struct stat *st);
 bool stat_is_md_dev(struct stat *st);
 extern char *fd2devnm(int fd);
-extern void udev_block(char *devnm);
-extern void udev_unblock(void);
 
 extern int in_initrd(void);
 

mdopen.c

@@ -23,6 +23,7 @@
  */
 
 #include "mdadm.h"
+#include "udev.h"
 #include "md_p.h"
 #include <ctype.h>
 
@@ -176,7 +177,7 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 	char devnm[32];
 	char cbuf[400];
 
-	if (!use_udev())
+	if (!udev_is_available())
 		block_udev = 0;
 
 	if (chosen == NULL)
@@ -335,8 +336,8 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 	devnm[0] = 0;
 	if (num < 0 && cname && ci->names) {
 		sprintf(devnm, "md_%s", cname);
-		if (block_udev)
+		if (block_udev && udev_block(devnm) != UDEV_STATUS_SUCCESS)
-			udev_block(devnm);
+			return -1;
 		if (!create_named_array(devnm)) {
 			devnm[0] = 0;
 			udev_unblock();
@@ -344,8 +345,8 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 	}
 	if (num >= 0) {
 		sprintf(devnm, "md%d", num);
-		if (block_udev)
+		if (block_udev && udev_block(devnm) != UDEV_STATUS_SUCCESS)
-			udev_block(devnm);
+			return -1;
 		if (!create_named_array(devnm)) {
 			devnm[0] = 0;
 			udev_unblock();
@@ -368,8 +369,8 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 				return -1;
 			}
 		}
-		if (block_udev)
+		if (block_udev && udev_block(devnm) != UDEV_STATUS_SUCCESS)
-			udev_block(devnm);
+			return -1;
 		create_named_array(devnm);
 	}
 
@@ -384,7 +385,7 @@ int create_mddev(char *dev, char *name, int autof, int trustworthy,
 	 * If we cannot detect udev, we need to make
 	 * devices and links ourselves.
 	 */
-	if (!use_udev()) {
+	if (!udev_is_available()) {
 		/* Make sure 'devname' exists and 'chosen' is a symlink to it */
 		if (lstat(devname, &stb) == 0) {
 			/* Must be the correct device, else error */
@@ -508,7 +509,7 @@ char *find_free_devnm(int use_partitions)
 			continue;
 		if (!conf_name_is_free(devnm))
 			continue;
-		if (!use_udev()) {
+		if (!udev_is_available()) {
 			/* make sure it is new to /dev too, at least as a
 			 * non-standard */
 			dev_t devid = devnm2devid(devnm);

udev.c

@@ -0,0 +1,194 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2022 Mateusz Grzonka <mateusz.grzonka@intel.com>
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include	"mdadm.h"
+#include	"udev.h"
+#include	"md_p.h"
+#include	"md_u.h"
+#include	<sys/wait.h>
+#include	<signal.h>
+#include	<limits.h>
+#include	<syslog.h>
+#include	<libudev.h>
+
+static char *unblock_path;
+
+/*
+ * udev_is_available() - Checks for udev in the system.
+ *
+ * Function looks whether udev directories are available and MDADM_NO_UDEV env defined.
+ *
+ * Return:
+ * true if udev is available,
+ * false if not
+ */
+bool udev_is_available(void)
+{
+	struct stat stb;
+
+	if (stat("/dev/.udev", &stb) != 0 &&
+	    stat("/run/udev", &stb) != 0)
+		return false;
+	if (check_env("MDADM_NO_UDEV") == 1)
+		return false;
+	return true;
+}
+
+#ifndef NO_LIBUDEV
+
+static struct udev *udev;
+static struct udev_monitor *udev_monitor;
+
+/*
+ * udev_release() - Drops references of udev and udev_monitor.
+ */
+static void udev_release(void)
+{
+	udev_monitor_unref(udev_monitor);
+	udev_unref(udev);
+}
+
+/*
+ * udev_initialize() - Initializes udev and udev_monitor structures.
+ *
+ * Function initializes udev, udev_monitor, and sets udev_monitor filter for block devices.
+ *
+ * Return:
+ * UDEV_STATUS_SUCCESS on success
+ * UDEV_STATUS_ERROR on error
+ * UDEV_STATUS_ERROR_NO_UDEV when udev not available
+ */
+static enum udev_status udev_initialize(void)
+{
+	if (!udev_is_available()) {
+		pr_err("No udev.\n");
+		return UDEV_STATUS_ERROR_NO_UDEV;
+	}
+
+	udev = udev_new();
+	if (!udev) {
+		pr_err("Cannot initialize udev.\n");
+		return UDEV_STATUS_ERROR;
+	}
+
+	udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
+	if (!udev_monitor) {
+		pr_err("Cannot initialize udev monitor.\n");
+		udev = udev_unref(udev);
+		return UDEV_STATUS_ERROR;
+	}
+
+	if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, "block", 0) < 0) {
+		pr_err("Cannot add udev monitor event filter for md devices.\n");
+		udev_release();
+		return UDEV_STATUS_ERROR;
+	}
+	if (udev_monitor_enable_receiving(udev_monitor) < 0) {
+		pr_err("Cannot enable receiving udev events through udev monitor.\n");
+		udev_release();
+		return UDEV_STATUS_ERROR;
+	}
+	atexit(udev_release);
+	return UDEV_STATUS_SUCCESS;
+}
+
+/*
+ * udev_wait_for_events() - Waits for events from udev.
+ * @seconds: Timeout in seconds.
+ *
+ * Function waits udev events, wakes up on event or timeout.
+ *
+ * Return:
+ * UDEV_STATUS_SUCCESS on detected event
+ * UDEV_STATUS_TIMEOUT on timeout
+ * UDEV_STATUS_ERROR on error
+ */
+enum udev_status udev_wait_for_events(int seconds)
+{
+	int fd;
+	fd_set readfds;
+	struct timeval tv;
+	int ret;
+
+	if (!udev || !udev_monitor) {
+		ret = udev_initialize();
+		if (ret != UDEV_STATUS_SUCCESS)
+			return ret;
+	}
+
+	fd = udev_monitor_get_fd(udev_monitor);
+	if (fd < 0) {
+		pr_err("Cannot access file descriptor associated with udev monitor.\n");
+		return UDEV_STATUS_ERROR;
+	}
+
+	FD_ZERO(&readfds);
+	FD_SET(fd, &readfds);
+	tv.tv_sec = seconds;
+	tv.tv_usec = 0;
+
+	if (select(fd + 1, &readfds, NULL, NULL, &tv) > 0 && FD_ISSET(fd, &readfds))
+		if (udev_monitor_receive_device(udev_monitor))
+			return UDEV_STATUS_SUCCESS; /* event detected */
+	return UDEV_STATUS_TIMEOUT;
+}
+#endif
+
+/*
+ * udev_block() - Block udev from examining newly created arrays.
+ *
+ * When array is created, we don't want udev to examine it immediately.
+ * Function creates /run/mdadm/creating-mdXXX and expects that udev rule
+ * will notice it and act accordingly.
+ *
+ * Return:
+ * UDEV_STATUS_SUCCESS when successfully blocked udev
+ * UDEV_STATUS_ERROR on error
+ */
+enum udev_status udev_block(char *devnm)
+{
+	int fd;
+	char *path = xcalloc(1, BUFSIZ);
+
+	snprintf(path, BUFSIZ, "/run/mdadm/creating-%s", devnm);
+
+	fd = open(path, O_CREAT | O_RDWR, 0600);
+	if (!is_fd_valid(fd)) {
+		pr_err("Cannot block udev, error creating blocking file.\n");
+		pr_err("%s: %s\n", strerror(errno), path);
+		free(path);
+		return UDEV_STATUS_ERROR;
+	}
+
+	close(fd);
+	unblock_path = path;
+	return UDEV_STATUS_SUCCESS;
+}
+
+/*
+ * udev_unblock() - Unblock udev.
+ */
+void udev_unblock(void)
+{
+	if (unblock_path)
+		unlink(unblock_path);
+	free(unblock_path);
+	unblock_path = NULL;
+}

udev.h

@@ -0,0 +1,40 @@
+/*
+ * mdadm - manage Linux "md" devices aka RAID arrays.
+ *
+ * Copyright (C) 2022 Mateusz Grzonka <mateusz.grzonka@intel.com>
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef MONITOR_UDEV_H
+#define MONITOR_UDEV_H
+
+enum udev_status {
+	UDEV_STATUS_ERROR_NO_UDEV = -2,
+	UDEV_STATUS_ERROR,
+	UDEV_STATUS_SUCCESS = 0,
+	UDEV_STATUS_TIMEOUT
+};
+
+bool udev_is_available(void);
+
+#ifndef NO_LIBUDEV
+enum udev_status udev_wait_for_events(int seconds);
+#endif
+
+enum udev_status udev_block(char *devnm);
+void udev_unblock(void);
+
+#endif