- Proc locking.

- Use queue macros.
- Use NULL instead of 0 for pointers.

Reviewed by:	des

3 files changed, 73 insertions, 27 deletions

diff --git a/sys/compat/linprocfs/linprocfs.c b/sys/compat/linprocfs/linprocfs.c
index 86bc9fd..2e23fe7 100644
--- a/sys/compat/linprocfs/linprocfs.c
+++ b/sys/compat/linprocfs/linprocfs.c
@@ -127,8 +127,7 @@ linprocfs_domeminfo(curp, p, pfs, uio)
 	}
 	swapused = swaptotal - swapfree;
 	memshared = 0;
-	for (object = TAILQ_FIRST(&vm_object_list); object != NULL;
-	    object = TAILQ_NEXT(object, object_list))
+	TAILQ_FOREACH(object, &vm_object_list, object_list)
 		if (object->shadow_count > 1)
 			memshared += object->resident_page_count;
 	memshared *= PAGE_SIZE;
@@ -474,6 +473,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	 */
 	sbuf_printf(&sb, "Pid:\t%d\n",		p->p_pid);
 	sbuf_printf(&sb, "PPid:\t%d\n",		ppid);
+	PROC_LOCK(p);
 	sbuf_printf(&sb, "Uid:\t%d %d %d %d\n", p->p_cred->p_ruid,
 			                        p->p_ucred->cr_uid,
 			                        p->p_cred->p_svuid,
@@ -487,6 +487,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	sbuf_cat(&sb, "Groups:\t");
 	for (i = 0; i < p->p_ucred->cr_ngroups; i++)
 		sbuf_printf(&sb, "%d ", p->p_ucred->cr_groups[i]);
+	PROC_UNLOCK(p);
 	sbuf_putc(&sb, '\n');
 	
 	/*
@@ -521,6 +522,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	 * supports 64 signals, but this code is a long way from
 	 * running on anything but i386, so ignore that for now.
 	 */
+	PROC_LOCK(p);
 	sbuf_printf(&sb, "SigPnd:\t%08x\n",	p->p_siglist.__bits[0]);
 	/*
 	 * I can't seem to find out where the signal mask is in
@@ -529,6 +531,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	sbuf_printf(&sb, "SigBlk:\t%08x\n",	0); /* XXX */
 	sbuf_printf(&sb, "SigIgn:\t%08x\n",	p->p_sigignore.__bits[0]);
 	sbuf_printf(&sb, "SigCgt:\t%08x\n",	p->p_sigcatch.__bits[0]);
+	PROC_UNLOCK(p);
 	
 	/*
 	 * Linux also prints the capability masks, but we don't have
diff --git a/sys/compat/linprocfs/linprocfs_misc.c b/sys/compat/linprocfs/linprocfs_misc.c
index 86bc9fd..2e23fe7 100644
--- a/sys/compat/linprocfs/linprocfs_misc.c
+++ b/sys/compat/linprocfs/linprocfs_misc.c
@@ -127,8 +127,7 @@ linprocfs_domeminfo(curp, p, pfs, uio)
 	}
 	swapused = swaptotal - swapfree;
 	memshared = 0;
-	for (object = TAILQ_FIRST(&vm_object_list); object != NULL;
-	    object = TAILQ_NEXT(object, object_list))
+	TAILQ_FOREACH(object, &vm_object_list, object_list)
 		if (object->shadow_count > 1)
 			memshared += object->resident_page_count;
 	memshared *= PAGE_SIZE;
@@ -474,6 +473,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	 */
 	sbuf_printf(&sb, "Pid:\t%d\n",		p->p_pid);
 	sbuf_printf(&sb, "PPid:\t%d\n",		ppid);
+	PROC_LOCK(p);
 	sbuf_printf(&sb, "Uid:\t%d %d %d %d\n", p->p_cred->p_ruid,
 			                        p->p_ucred->cr_uid,
 			                        p->p_cred->p_svuid,
@@ -487,6 +487,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	sbuf_cat(&sb, "Groups:\t");
 	for (i = 0; i < p->p_ucred->cr_ngroups; i++)
 		sbuf_printf(&sb, "%d ", p->p_ucred->cr_groups[i]);
+	PROC_UNLOCK(p);
 	sbuf_putc(&sb, '\n');
 	
 	/*
@@ -521,6 +522,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	 * supports 64 signals, but this code is a long way from
 	 * running on anything but i386, so ignore that for now.
 	 */
+	PROC_LOCK(p);
 	sbuf_printf(&sb, "SigPnd:\t%08x\n",	p->p_siglist.__bits[0]);
 	/*
 	 * I can't seem to find out where the signal mask is in
@@ -529,6 +531,7 @@ linprocfs_doprocstatus(curp, p, pfs, uio)
 	sbuf_printf(&sb, "SigBlk:\t%08x\n",	0); /* XXX */
 	sbuf_printf(&sb, "SigIgn:\t%08x\n",	p->p_sigignore.__bits[0]);
 	sbuf_printf(&sb, "SigCgt:\t%08x\n",	p->p_sigcatch.__bits[0]);
+	PROC_UNLOCK(p);
 	
 	/*
 	 * Linux also prints the capability masks, but we don't have
diff --git a/sys/compat/linprocfs/linprocfs_vnops.c b/sys/compat/linprocfs/linprocfs_vnops.c
index fca2cdb..55e3f52 100644
--- a/sys/compat/linprocfs/linprocfs_vnops.c
+++ b/sys/compat/linprocfs/linprocfs_vnops.c
@@ -192,12 +192,15 @@ linprocfs_close(ap)
 		 * told to stop on an event, but then the requesting process
 		 * has gone away or forgotten about it.
 		 */
-		if ((ap->a_vp->v_usecount < 2)
-		    && (p = pfind(pfs->pfs_pid))
-		    && !(p->p_pfsflags & PF_LINGER)) {
-			p->p_stops = 0;
-			p->p_step = 0;
-			wakeup(&p->p_step);
+		if ((ap->a_vp->v_usecount < 2) && (p = pfind(pfs->pfs_pid))) {
+			PROC_LOCK(p);
+			if (!(p->p_pfsflags & PF_LINGER)) {
+				p->p_stops = 0;
+				p->p_step = 0;
+				PROC_UNLOCK(p);
+				wakeup(&p->p_step);
+			} else
+				PROC_UNLOCK(p);
 		}
 		break;
 	default:
@@ -232,10 +235,14 @@ linprocfs_ioctl(ap)
 
 	switch (ap->a_command) {
 	case PIOCBIS:
+	  PROC_LOCK(procp);
 	  procp->p_stops |= *(unsigned int*)ap->a_data;
+	  PROC_UNLOCK(procp);
 	  break;
 	case PIOCBIC:
+	  PROC_LOCK(procp);
 	  procp->p_stops &= ~*(unsigned int*)ap->a_data;
+	  PROC_UNLOCK(procp);
 	  break;
 	case PIOCSFL:
 	  /*
@@ -246,12 +253,18 @@ linprocfs_ioctl(ap)
 	  flags = (unsigned char)*(unsigned int*)ap->a_data;
 	  if (flags & NFLAGS && (error = suser(p)))
 	    return error;
+	  PROC_LOCK(procp);
 	  procp->p_pfsflags = flags;
+	  PROC_UNLOCK(procp);
 	  break;
 	case PIOCGFL:
+	  PROC_LOCK(procp);
 	  *(unsigned int*)ap->a_data = (unsigned int)procp->p_pfsflags;
+	  PROC_UNLOCK(procp);
+	  /* FALLTHROUGH */
 	case PIOCSTATUS:
 	  psp = (struct procfs_status *)ap->a_data;
+	  PROC_LOCK(procp);
 	  psp->state = (procp->p_step == 0);
 	  psp->flags = procp->p_pfsflags;
 	  psp->events = procp->p_stops;
@@ -261,29 +274,41 @@ linprocfs_ioctl(ap)
 	  } else {
 	    psp->why = psp->val = 0;	/* Not defined values */
 	  }
+	  PROC_UNLOCK(procp);
 	  break;
 	case PIOCWAIT:
 	  psp = (struct procfs_status *)ap->a_data;
+	  PROC_LOCK(procp);
 	  if (procp->p_step == 0) {
-	    error = tsleep(&procp->p_stype, PWAIT | PCATCH, "piocwait", 0);
-	    if (error)
+	    error = msleep(&procp->p_stype, &procp->p_mtx, PWAIT | PCATCH,
+	      "piocwait", 0);
+	    if (error) {
+	      PROC_UNLOCK(procp);
 	      return error;
+	    }
 	  }
 	  psp->state = 1;	/* It stopped */
 	  psp->flags = procp->p_pfsflags;
 	  psp->events = procp->p_stops;
 	  psp->why = procp->p_stype;	/* why it stopped */
 	  psp->val = procp->p_xstat;	/* any extra info */
+	  PROC_UNLOCK(procp);
 	  break;
 	case PIOCCONT:	/* Restart a proc */
-	  if (procp->p_step == 0)
+	  PROC_LOCK(procp);
+	  if (procp->p_step == 0) {
+	    PROC_UNLOCK(procp);
 	    return EINVAL;	/* Can only start a stopped process */
+	  }
+	  PROC_UNLOCK(procp);
 	  if ((signo = *(int*)ap->a_data) != 0) {
 	    if (signo >= NSIG || signo <= 0)
 	      return EINVAL;
 	    psignal(procp, signo);
 	  }
+	  PROC_LOCK(procp);
 	  procp->p_step = 0;
+	  PROC_UNLOCK(procp);
 	  wakeup(&procp->p_step);
 	  break;
 	default:
@@ -419,15 +444,19 @@ linprocfs_getattr(ap)
 	switch (pfs->pfs_type) {
 	case Proot:
 	case Pself:
-		procp = 0;
+		procp = NULL;
 		break;
 
 	default:
 		procp = PFIND(pfs->pfs_pid);
-		if (procp == 0 || procp->p_cred == NULL ||
-		    procp->p_ucred == NULL)
+		if (procp == NULL)
 			return (ENOENT);
-
+		PROC_LOCK(procp);
+		if (procp->p_cred == NULL || procp->p_ucred == NULL) {
+			PROC_UNLOCK(procp);
+			return (ENOENT);
+		}
+		PROC_UNLOCK(procp);
 		if (p_can(ap->a_p, procp, P_CAN_SEE, NULL))
 			return (ENOENT);
 	}
@@ -465,8 +494,10 @@ linprocfs_getattr(ap)
 	switch (pfs->pfs_type) {
 	case Pmem:
 		/* Retain group kmem readablity. */
+		PROC_LOCK(procp);
 		if (procp->p_flag & P_SUGID)
 			vap->va_mode &= ~(VREAD|VWRITE);
+		PROC_UNLOCK(procp);
 		break;
 	default:
 		break;
@@ -484,8 +515,10 @@ linprocfs_getattr(ap)
 
 	vap->va_nlink = 1;
 	if (procp) {
+		PROC_LOCK(procp);
 		vap->va_uid = procp->p_ucred->cr_uid;
 		vap->va_gid = procp->p_ucred->cr_gid;
+		PROC_UNLOCK(procp);
 	}
 
 	switch (pfs->pfs_type) {
@@ -543,10 +576,12 @@ linprocfs_getattr(ap)
 		 * change the owner to root - otherwise 'ps' and friends
 		 * will break even though they are setgid kmem. *SIGH*
 		 */
+		PROC_LOCK(procp);
 		if (procp->p_flag & P_SUGID)
 			vap->va_uid = 0;
 		else
 			vap->va_uid = procp->p_ucred->cr_uid;
+		PROC_UNLOCK(procp);
 		vap->va_gid = KMEM_GROUP;
 		break;
 
@@ -705,7 +740,7 @@ linprocfs_lookup(ap)
 			break;
 
 		p = PFIND(pid);
-		if (p == 0)
+		if (p == NULL)
 			break;
 
 		if (p_can(curp, p, P_CAN_SEE, NULL))
@@ -718,7 +753,7 @@ linprocfs_lookup(ap)
 			return (linprocfs_root(dvp->v_mount, vpp));
 
 		p = PFIND(pfs->pfs_pid);
-		if (p == 0)
+		if (p == NULL)
 			break;
 
 		for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) {
@@ -843,7 +878,7 @@ linprocfs_readdir(ap)
 		struct proc *p;
 
 		ALLPROC_LOCK(AP_SHARED);
-		p = allproc.lh_first;
+		p = LIST_FIRST(&allproc);
 		for (; p && uio->uio_resid >= delen; i++, pcnt++) {
 			bzero((char *) dp, delen);
 			dp->d_reclen = delen;
@@ -902,23 +937,23 @@ linprocfs_readdir(ap)
 
 			default:
 				while (pcnt < i) {
-					p = p->p_list.le_next;
-					if (!p)
+					p = LIST_NEXT(p, p_list);
+					if (p == NULL)
 						goto done;
 					if (p_can(curproc, p, P_CAN_SEE, NULL))
 						continue;
 					pcnt++;
 				}
 				while (p_can(curproc, p, P_CAN_SEE, NULL)) {
-					p = p->p_list.le_next;
-					if (!p)
+					p = LIST_NEXT(p, p_list);
+					if (p == NULL)
 						goto done;
 				}
 				dp->d_fileno = PROCFS_FILENO(p->p_pid, Pproc);
 				dp->d_namlen = sprintf(dp->d_name, "%ld",
 				    (long)p->p_pid);
 				dp->d_type = DT_DIR;
-				p = p->p_list.le_next;
+				p = LIST_NEXT(p, p_list);
 				break;
 			}
 
@@ -928,9 +963,9 @@ linprocfs_readdir(ap)
 	done:
 
 #ifdef PROCFS_ZOMBIE
-		if (p == 0 && doingzomb == 0) {
+		if (p == NULL && doingzomb == 0) {
 			doingzomb = 1;
-			p = zombproc.lh_first;
+			p = LIST_FIRST(&zombproc);
 			goto again;
 		}
 #endif
@@ -978,13 +1013,18 @@ linprocfs_readlink(ap)
 	 */
 	case Pexe:
 		procp = PFIND(pfs->pfs_pid);
+		if (procp != NULL)
+			PROC_LOCK(procp);
 		if (procp == NULL || procp->p_cred == NULL ||
 		    procp->p_ucred == NULL) {
+			if (procp != NULL)
+				PROC_UNLOCK(procp);
 			printf("linprocfs_readlink: pid %d disappeared\n",
 			    pfs->pfs_pid);
 			return (uiomove("unknown", sizeof("unknown") - 1,
 			    ap->a_uio));
 		}
+		PROC_UNLOCK(procp);
 		error = textvp_fullpath(procp, &fullpath, &freepath);
 		if (error != 0)
 			return (uiomove("unknown", sizeof("unknown") - 1,