svn commit: r364425 - head/sys/kern

[Warner Losh]

Author: imp
Date: Thu Aug 20 16:52:48 2020
New Revision: 364425
URL: https://svnweb.freebsd.org/changeset/base/364425

Log:
  Use names suggested by kib@ in review D25969, move call for unmount to not call
  with vnode locked, use NOWAIT alloc and only report when we don't overflow.
  
  These changes were accidentally omitted from r364402, except for the not
  reporting on overflow. They were lumped in with a debugging commit in my tree
  that I omitted w/o realizing this.
  
  Other issues from the review are pending some other changes I need to do first.

Modified:
  head/sys/kern/vfs_mount.c

Modified: head/sys/kern/vfs_mount.c
==============================================================================
--- head/sys/kern/vfs_mount.c	Thu Aug 20 16:52:34 2020	(r364424)
+++ head/sys/kern/vfs_mount.c	Thu Aug 20 16:52:48 2020	(r364425)
@@ -102,7 +102,7 @@ MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MT
 EVENTHANDLER_LIST_DEFINE(vfs_mounted);
 EVENTHANDLER_LIST_DEFINE(vfs_unmounted);
 
-static void dev_vfs_event(const char *type, struct mount *mp, bool donew);
+static void mount_devctl_event(const char *type, struct mount *mp, bool donew);
 
 /*
  * Global opts, taken by all filesystems
@@ -1023,7 +1023,7 @@ vfs_domount_first(
 	VOP_UNLOCK(vp);
 	EVENTHANDLER_DIRECT_INVOKE(vfs_mounted, mp, newdp, td);
 	VOP_UNLOCK(newdp);
-	dev_vfs_event("MOUNT", mp, false);
+	mount_devctl_event("MOUNT", mp, false);
 	mountcheckdirs(vp, newdp);
 	vn_seqc_write_end(vp);
 	vn_seqc_write_end(newdp);
@@ -1225,7 +1225,7 @@ vfs_domount_update(
 	if (error != 0)
 		goto end;
 
-	dev_vfs_event("REMOUNT", mp, true);
+	mount_devctl_event("REMOUNT", mp, true);
 	if (mp->mnt_opt != NULL)
 		vfs_freeopts(mp->mnt_opt);
 	mp->mnt_opt = mp->mnt_optnew;
@@ -1844,13 +1844,13 @@ dounmount(struct mount *mp, int flags, struct thread *
 	TAILQ_REMOVE(&mountlist, mp, mnt_list);
 	mtx_unlock(&mountlist_mtx);
 	EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td);
-	dev_vfs_event("UNMOUNT", mp, false);
 	if (coveredvp != NULL) {
 		coveredvp->v_mountedhere = NULL;
 		vn_seqc_write_end(coveredvp);
 		VOP_UNLOCK(coveredvp);
 		vdrop(coveredvp);
 	}
+	mount_devctl_event("UNMOUNT", mp, false);
 	if (rootvp != NULL) {
 		vn_seqc_write_end(rootvp);
 		vdrop(rootvp);
@@ -2439,7 +2439,7 @@ static struct mntoptnames optnames[] = {
 };
 
 static void
-dev_vfs_event_mntopt(struct sbuf *sb, const char *what, struct vfsoptlist *opts)
+mount_devctl_event_mntopt(struct sbuf *sb, const char *what, struct vfsoptlist *opts)
 {
 	struct vfsopt *opt;
 
@@ -2461,7 +2461,7 @@ dev_vfs_event_mntopt(struct sbuf *sb, const char *what
 
 #define DEVCTL_LEN 1024
 static void
-dev_vfs_event(const char *type, struct mount *mp, bool donew)
+mount_devctl_event(const char *type, struct mount *mp, bool donew)
 {
 	const uint8_t *cp;
 	struct mntoptnames *fp;
@@ -2469,7 +2469,7 @@ dev_vfs_event(const char *type, struct mount *mp, bool
 	struct statfs *sfp = &mp->mnt_stat;
 	char *buf;
 
-	buf = malloc(DEVCTL_LEN, M_MOUNT, M_WAITOK);
+	buf = malloc(DEVCTL_LEN, M_MOUNT, M_NOWAIT);
 	if (buf == NULL)
 		return;
 	sbuf_new(&sb, buf, DEVCTL_LEN, SBUF_FIXEDLEN);
@@ -2491,12 +2491,13 @@ dev_vfs_event(const char *type, struct mount *mp, bool
 		}
 	}
 	sbuf_putc(&sb, '"');
-	dev_vfs_event_mntopt(&sb, "opt", mp->mnt_opt);
+	mount_devctl_event_mntopt(&sb, "opt", mp->mnt_opt);
 	if (donew)
-		dev_vfs_event_mntopt(&sb, "optnew", mp->mnt_optnew);
+		mount_devctl_event_mntopt(&sb, "optnew", mp->mnt_optnew);
 	sbuf_finish(&sb);
 
-	devctl_notify("VFS", "FS", type, sbuf_data(&sb));
+	if (sbuf_error(&sb) == 0)
+		devctl_notify("VFS", "FS", type, sbuf_data(&sb));
 	sbuf_delete(&sb);
 	free(buf, M_MOUNT);
 }