From 8ec21e3a681045e210cc6393cecee86fab14bb6e Mon Sep 17 00:00:00 2001
From: Poul-Henning Kamp <phk@FreeBSD.org>
Date: Sun, 7 Nov 2004 12:39:28 +0000
Subject: [PATCH] Allow fdinit() to be called with a NULL fdp argument so we
 can use it when setting up init.

Make fdinit() lock the fdp argument as needed.
---
 sys/kern/init_main.c    | 17 +++--------------
 sys/kern/kern_descrip.c | 31 ++++++++++++++++---------------
 sys/kern/kern_fork.c    |  4 ----
 3 files changed, 19 insertions(+), 33 deletions(-)

diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index e23e44608108..4b94b5baa8d3 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -91,7 +91,6 @@ static struct pgrp pgrp0;
 struct	proc proc0;
 struct	thread thread0;
 struct	ksegrp ksegrp0;
-static struct filedesc0 filedesc0;
 struct	vmspace vmspace0;
 struct	proc *initproc;
 
@@ -314,9 +313,8 @@ struct sysentvec null_sysvec = {
 static void
 proc0_init(void *dummy __unused)
 {
-	register struct proc		*p;
-	register struct filedesc0	*fdp;
-	register unsigned i;
+	struct proc *p;
+	unsigned i;
 	struct thread *td;
 	struct ksegrp *kg;
 
@@ -406,17 +404,8 @@ proc0_init(void *dummy __unused)
 	siginit(&proc0);
 
 	/* Create the file descriptor table. */
-	/* XXX this duplicates part of fdinit() */
-	fdp = &filedesc0;
-	p->p_fd = &fdp->fd_fd;
+	p->p_fd = fdinit(NULL);
 	p->p_fdtol = NULL;
-	mtx_init(&fdp->fd_fd.fd_mtx, FILEDESC_LOCK_DESC, NULL, MTX_DEF);
-	fdp->fd_fd.fd_refcnt = 1;
-	fdp->fd_fd.fd_cmask = CMASK;
-	fdp->fd_fd.fd_ofiles = fdp->fd_dfiles;
-	fdp->fd_fd.fd_ofileflags = fdp->fd_dfileflags;
-	fdp->fd_fd.fd_nfiles = NDFILE;
-	fdp->fd_fd.fd_map = fdp->fd_dmap;
 
 	/* Create the limits structures. */
 	p->p_limit = lim_alloc();
diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index 132f326cbda7..85beee076205 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -1403,22 +1403,21 @@ fdinit(fdp)
 {
 	struct filedesc0 *newfdp;
 
-	FILEDESC_LOCK_ASSERT(fdp, MA_OWNED);
-
-	FILEDESC_UNLOCK(fdp);
-	MALLOC(newfdp, struct filedesc0 *, sizeof(struct filedesc0),
-	    M_FILEDESC, M_WAITOK | M_ZERO);
-	FILEDESC_LOCK(fdp);
+	newfdp = malloc(sizeof *newfdp, M_FILEDESC, M_WAITOK | M_ZERO);
 	mtx_init(&newfdp->fd_fd.fd_mtx, FILEDESC_LOCK_DESC, NULL, MTX_DEF);
-	newfdp->fd_fd.fd_cdir = fdp->fd_cdir;
-	if (newfdp->fd_fd.fd_cdir)
-		VREF(newfdp->fd_fd.fd_cdir);
-	newfdp->fd_fd.fd_rdir = fdp->fd_rdir;
-	if (newfdp->fd_fd.fd_rdir)
-		VREF(newfdp->fd_fd.fd_rdir);
-	newfdp->fd_fd.fd_jdir = fdp->fd_jdir;
-	if (newfdp->fd_fd.fd_jdir)
-		VREF(newfdp->fd_fd.fd_jdir);
+	if (fdp != NULL) {
+		FILEDESC_LOCK(fdp);
+		newfdp->fd_fd.fd_cdir = fdp->fd_cdir;
+		if (newfdp->fd_fd.fd_cdir)
+			VREF(newfdp->fd_fd.fd_cdir);
+		newfdp->fd_fd.fd_rdir = fdp->fd_rdir;
+		if (newfdp->fd_fd.fd_rdir)
+			VREF(newfdp->fd_fd.fd_rdir);
+		newfdp->fd_fd.fd_jdir = fdp->fd_jdir;
+		if (newfdp->fd_fd.fd_jdir)
+			VREF(newfdp->fd_fd.fd_jdir);
+		FILEDESC_UNLOCK(fdp);
+	}
 
 	/* Create the file descriptor table. */
 	newfdp->fd_fd.fd_refcnt = 1;
@@ -1460,7 +1459,9 @@ fdcopy(fdp)
 		return (NULL);
 
 	FILEDESC_LOCK_ASSERT(fdp, MA_OWNED);
+	FILEDESC_UNLOCK(fdp);
 	newfdp = fdinit(fdp);
+	FILEDESC_LOCK(fdp);
 	while (fdp->fd_lastfile >= newfdp->fd_nfiles) {
 		FILEDESC_UNLOCK(fdp);
 		FILEDESC_LOCK(newfdp);
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index 714a1af63b59..f90ff3280c7d 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -225,9 +225,7 @@ fork1(td, flags, pages, procp)
 		 */
 		if (flags & RFCFDG) {
 			struct filedesc *fdtmp;
-			FILEDESC_LOCK(td->td_proc->p_fd);
 			fdtmp = fdinit(td->td_proc->p_fd);
-			FILEDESC_UNLOCK(td->td_proc->p_fd);
 			fdfree(td);
 			p1->p_fd = fdtmp;
 		}
@@ -423,9 +421,7 @@ fork1(td, flags, pages, procp)
 	 * Copy filedesc.
 	 */
 	if (flags & RFCFDG) {
-		FILEDESC_LOCK(td->td_proc->p_fd);
 		fd = fdinit(td->td_proc->p_fd);
-		FILEDESC_UNLOCK(td->td_proc->p_fd);
 		fdtol = NULL;
 	} else if (flags & RFFDG) {
 		FILEDESC_LOCK(p1->p_fd);