mdstat_ent handling rework

Assemble.c

@@ -23,6 +23,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"xmalloc.h"
 
 #include	<ctype.h>
@@ -120,7 +121,7 @@ static int is_member_busy(char *metadata_version)
 			continue;
 
 		/* Skip first char - it can be '/' or '-' */
-		if (strcmp(&ent->metadata_version[10], metadata_version + 1) == 0) {
+		if (strcmp(&ent->metadata_version[MD_VER_EXT_LEN + 1], metadata_version + 1) == 0) {
 			busy = 1;
 			break;
 		}

Detail.c

@@ -23,6 +23,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"xmalloc.h"
 
 #include	<ctype.h>
@@ -683,10 +684,10 @@ int Detail(char *dev, struct context *c)
 					de->d_name);
 				if (load_sys(path, vbuf, sizeof(vbuf)) < 0)
 					continue;
-				if (strncmp(vbuf, "external:", 9) ||
-				    !is_subarray(vbuf + 9) ||
-				    strncmp(vbuf + 10, sra->sys_name, nlen) ||
-				    vbuf[10 + nlen] != '/')
+				if (strncmp(vbuf, MD_VER_EXT, MD_VER_EXT_LEN) ||
+				    !is_subarray(vbuf + MD_VER_EXT_LEN) ||
+				    strncmp(vbuf + MD_VER_EXT_LEN + 1, sra->sys_name, nlen) ||
+				    vbuf[MD_VER_EXT_LEN + 1 + nlen] != '/')
 					continue;
 				devid = devnm2devid(de->d_name);
 				printf(" %s",

Grow.c

@@ -22,6 +22,7 @@
  *    Email: <neilb@suse.de>
  */
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"dlink.h"
 #include	"xmalloc.h"
 
@@ -696,7 +697,7 @@ static int check_idle(struct supertype *st)
 		if (!is_container_member(e, container))
 			continue;
 		/* frozen array is not idle*/
-		if (e->percent >= 0 || e->metadata_version[9] == '-') {
+		if (e->percent >= 0 || e->metadata_version[MD_VER_BLOCKED_IDX] == '-') {
 			is_idle = 0;
 			break;
 		}

Incremental.c

@@ -29,6 +29,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"xmalloc.h"
 #include	"udev.h"
 

Kill.c

@@ -26,6 +26,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 
 int Kill(char *dev, struct supertype *st, int force, int verbose, int noexcl)
 {

Manage.c

@@ -23,6 +23,7 @@
  */
 
 #include "mdadm.h"
+#include "mdstat.h"
 #include "udev.h"
 #include "xmalloc.h"
 
@@ -48,12 +49,12 @@ int Manage_ro(char *devname, int fd, int readonly)
 	    mdi->array.major_version == -1 &&
 	    is_subarray(mdi->text_version)) {
 		char vers[64];
-		strcpy(vers, "external:");
+		strcpy(vers, MD_VER_EXT);
 		strcat(vers, mdi->text_version);
 		if (readonly > 0) {
 			int rv;
 			/* We set readonly ourselves. */
-			vers[9] = '-';
+			vers[MD_VER_BLOCKED_IDX] = '-';
 			sysfs_set_str(mdi, NULL, "metadata_version", vers);
 
 			close_fd(&fd);
@@ -63,21 +64,21 @@ int Manage_ro(char *devname, int fd, int readonly)
 				pr_err("failed to set readonly for %s: %s\n",
 					devname, strerror(errno));
 
-				vers[9] = mdi->text_version[0];
+				vers[MD_VER_BLOCKED_IDX] = mdi->text_version[0];
 				sysfs_set_str(mdi, NULL, "metadata_version", vers);
 				rv = 1;
 				goto out;
 			}
 		} else {
 			char *cp;
 			/* We cannot set read/write - must signal mdmon */
-			vers[9] = '/';
+			vers[MD_VER_BLOCKED_IDX] = '/';
 			sysfs_set_str(mdi, NULL, "metadata_version", vers);
 
-			cp = strchr(vers+10, '/');
+			cp = strchr(vers + MD_VER_BLOCKED_IDX + 1, '/');
 			if (cp)
 				*cp = 0;
-			ping_monitor(vers+10);
+			ping_monitor(vers + MD_VER_BLOCKED_IDX + 1);
 			if (mdi->array.level <= 0)
 				sysfs_set_str(mdi, NULL, "array_state", "active");
 		}
@@ -278,7 +279,8 @@ int Manage_stop(char *devname, int fd, int verbose, int will_retry)
 		mds = mdstat_read(0, 0);
 		for (m = mds; m; m = m->next)
 			if (is_mdstat_ent_external(m) &&
-			    metadata_container_matches(m->metadata_version + 9, devnm)) {
+			    metadata_container_matches(m->metadata_version + MD_VER_EXT_LEN,
+			    devnm)) {
 				if (verbose >= 0)
 					pr_err("Cannot stop container %s: member %s still active\n",
 					       devname, m->devnm);

config.c

@@ -23,6 +23,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"dlink.h"
 #include	"xmalloc.h"
 

managemon.c

@@ -103,6 +103,7 @@
 #define _GNU_SOURCE
 #endif
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"mdmon.h"
 #include	"xmalloc.h"
 

mapfile.c

@@ -43,6 +43,7 @@
  * at compile time via MAP_DIR and MAP_FILE.
  */
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"xmalloc.h"
 
 #include	<sys/file.h>

md_common.h

@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * md_common - constants shared between md driver abstractions.
+ */
+
+#ifndef MD_COMMON_H
+#define MD_COMMON_H
+
+/*
+ * Prefix used by the md driver version to mark an externally-managed array or
+ * container. The full form is:
+ *
+ *   "external:" [/-] containername [/subarray]
+ *
+ * The '/' or '-' separator distinguishes normal read-write arrays from those
+ * that mdmon must not reconfigure (read-only, reshaping, etc.).
+ */
+#define MD_EXT                  "external" /* The external keyword used in various contexts */
+
+#define MD_VER_EXT	        "external:" /* The "external:" version const prefix */
+#define MD_VER_EXT_LEN	(sizeof(MD_VER_EXT) - 1) /* Length of external prefix */
+
+/* Index of the character that blocks the version.
+ * It is the one after the prefix so the array index is MD_VER_EXT_LEN
+ */
+#define MD_VER_BLOCKED_IDX (MD_VER_EXT_LEN)
+
+#endif

mdadm.c

@@ -26,6 +26,7 @@
  */
 
 #include "mdadm.h"
+#include "mdstat.h"
 #include "md_p.h"
 #include "xmalloc.h"
 

mdadm.h

@@ -684,36 +684,6 @@ typedef struct mapping {
 	int num;
 } mapping_t;
 
-struct mdstat_ent {
-	char		devnm[32];
-	int		active;
-	char		*level;
-	char		*pattern; /* U for up, _ for down */
-	int		percent; /* -1 if no resync */
-	int		resync; /* 3 if check, 2 if reshape, 1 if resync, 0 if recovery */
-	int		devcnt;
-	int		raid_disks;
-	char *		metadata_version;
-	struct dev_member {
-		char			*name;
-		struct dev_member	*next;
-	}		*members;
-	struct mdstat_ent *next;
-};
-
-extern struct mdstat_ent *mdstat_read(int hold, int start);
-extern void mdstat_close(void);
-extern void free_mdstat(struct mdstat_ent *ms);
-extern int mdstat_wait(int seconds);
-extern void mdstat_wait_fd(int fd, const sigset_t *sigmask);
-extern int mddev_busy(char *devnm);
-extern struct mdstat_ent *mdstat_by_component(char *name);
-extern struct mdstat_ent *mdstat_find_by_member_name(struct mdstat_ent *mdstat, char *member_devnm);
-extern struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container);
-
-extern bool is_mdstat_ent_external(struct mdstat_ent *ent);
-extern bool is_mdstat_ent_subarray(struct mdstat_ent *ent);
-
 struct map_ent {
 	struct map_ent *next;
 	char	devnm[32];
@@ -1727,8 +1697,6 @@ extern int is_mddev(char *dev);
 extern int open_container(int fd);
 extern int metadata_container_matches(char *metadata, char *devnm);
 extern int metadata_subdev_matches(char *metadata, char *devnm);
-extern bool is_container_member(struct mdstat_ent *ent, char *devname);
-extern int is_subarray_active(char *subarray, char *devname);
 extern int open_subarray(char *dev, char *subarray, struct supertype *st, int quiet);
 extern struct superswitch *version_to_superswitch(char *vers);
 
@@ -1823,11 +1791,6 @@ static inline int is_subarray(char *vers)
 	return (*vers == '/' || *vers == '-');
 }
 
-static inline char *to_subarray(struct mdstat_ent *ent, char *container)
-{
-	return &ent->metadata_version[10+strlen(container)+1];
-}
-
 /**
  * signal_s() - Wrapper for sigaction() with signal()-like interface.
  * @sig: The signal to set the signal handler to.

mdmon.c

@@ -64,6 +64,7 @@
 #endif
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"mdmon.h"
 #include	"xmalloc.h"
 

mdmon.h

@@ -84,9 +84,6 @@ void do_manager(struct supertype *container);
 extern volatile sig_atomic_t sigterm;
 
 int read_dev_state(int fd);
-bool is_container_member(struct mdstat_ent *mdstat, char *container);
-
-struct mdstat_ent *mdstat_read(int hold, int start);
 
 extern int exit_now, manager_ready;
 extern int mon_tid, mgr_tid;

mdmonitor.c

@@ -23,6 +23,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"udev.h"
 #include	"xmalloc.h"
 
@@ -892,7 +893,8 @@ static int check_array(struct state *st, struct mdstat_ent *mdstat,
 
 	if (is_mdstat_ent_subarray(mse)) {
 		char *sl;
-		snprintf(st->parent_devnm, MD_NAME_MAX, "%s", mse->metadata_version + 10);
+		snprintf(st->parent_devnm, MD_NAME_MAX, "%s",
+			 mse->metadata_version + MD_VER_EXT_LEN + 1);
 		sl = strchr(st->parent_devnm, '/');
 		if (sl)
 			*sl = 0;
@@ -1005,7 +1007,7 @@ static int add_new_arrays(struct mdstat_ent *mdstat, struct state **statelist)
 				char *sl;
 
 				snprintf(st->parent_devnm, MD_NAME_MAX, "%s",
-					 mse->metadata_version + 10);
+					 mse->metadata_version + MD_VER_EXT_LEN + 1);
 				sl = strchr(st->parent_devnm, '/');
 				if (sl)
 					*sl = 0;
@@ -1306,8 +1308,8 @@ int Wait(char *dev)
 		}
 		if (!e || e->percent == RESYNC_NONE) {
 			if (e && is_mdstat_ent_external(e)) {
-				if (is_subarray(&e->metadata_version[9]))
-					ping_monitor(&e->metadata_version[9]);
+				if (is_subarray(&e->metadata_version[MD_VER_EXT_LEN]))
+					ping_monitor(&e->metadata_version[MD_VER_EXT_LEN]);
 				else
 					ping_monitor(devnm);
 			}

mdopen.c

@@ -23,6 +23,7 @@
  */
 
 #include "mdadm.h"
+#include "mdstat.h"
 #include "udev.h"
 #include "md_p.h"
 #include "xmalloc.h"

mdstat.c

@@ -79,6 +79,7 @@
  */
 
 #include	"mdadm.h"
+#include	"mdstat.h"
 #include	"dlink.h"
 #include	"xmalloc.h"
 
@@ -155,27 +156,42 @@ bool is_mdstat_ent_external(struct mdstat_ent *ent)
 	if (!ent->metadata_version)
 		return false;
 
-	if (strncmp(ent->metadata_version, "external:", 9) == 0)
+	if (strncmp(ent->metadata_version, MD_VER_EXT, MD_VER_EXT_LEN) == 0)
 		return true;
 	return false;
 }
 
 bool is_mdstat_ent_subarray(struct mdstat_ent *ent)
 {
-	if (is_mdstat_ent_external(ent) && is_subarray(ent->metadata_version + 9))
+	if (is_mdstat_ent_external(ent) && is_subarray(ent->metadata_version + MD_VER_EXT_LEN))
 		return true;
 	return false;
 }
 
 bool is_container_member(struct mdstat_ent *mdstat, char *container)
 {
 	if (is_mdstat_ent_external(mdstat) &&
-	    metadata_container_matches(mdstat->metadata_version + 9, container))
+	    metadata_container_matches(mdstat->metadata_version + MD_VER_EXT_LEN, container))
 		return true;
 
 	return false;
 }
 
+int is_subarray_active(char *subarray, char *container)
+{
+	struct mdstat_ent *mdstat = mdstat_read(0, 0);
+	struct mdstat_ent *ent;
+
+	for (ent = mdstat; ent; ent = ent->next)
+		if (is_container_member(ent, container))
+			if (strcmp(to_subarray(ent, container), subarray) == 0)
+				break;
+
+	free_mdstat(mdstat);
+
+	return ent != NULL;
+}
+
 static int mdstat_fd = -1;
 struct mdstat_ent *mdstat_read(int hold, int start)
 {
@@ -493,9 +509,9 @@ struct mdstat_ent *mdstat_by_subdev(char *subdev, char *container)
 		if (!is_mdstat_ent_external(ent))
 			continue;
 
-		if (!metadata_container_matches(ent->metadata_version + 9, container))
+		if (!metadata_container_matches(ent->metadata_version + MD_VER_EXT_LEN, container))
 			continue;
-		if (!metadata_subdev_matches(ent->metadata_version + 9, subdev))
+		if (!metadata_subdev_matches(ent->metadata_version + MD_VER_EXT_LEN, subdev))
 			continue;
 
 		break;