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-rw-r--r--sys/src/9/port/chan.c227
-rw-r--r--sys/src/9/port/pgrp.c68
-rw-r--r--sys/src/9/port/portdat.h4
3 files changed, 97 insertions, 202 deletions
diff --git a/sys/src/9/port/chan.c b/sys/src/9/port/chan.c
index 785b449ef..41b686170 100644
--- a/sys/src/9/port/chan.c
+++ b/sys/src/9/port/chan.c
@@ -5,9 +5,6 @@
#include "fns.h"
#include "../port/error.h"
-int chandebug=0; /* toggled by sysr1 */
-#define DBG if(chandebug)iprint
-
enum
{
PATHSLOP = 20,
@@ -38,44 +35,6 @@ struct Elemlist
#define SEP(c) ((c) == 0 || (c) == '/')
-static void
-dumpmount(void) /* DEBUGGING */
-{
- Pgrp *pg;
- Mount *t;
- Mhead **h, **he, *f;
-
- if(up == nil){
- print("no process for dumpmount\n");
- return;
- }
- pg = up->pgrp;
- if(pg == nil){
- print("no pgrp for dumpmount\n");
- return;
- }
- rlock(&pg->ns);
- if(waserror()){
- runlock(&pg->ns);
- nexterror();
- }
-
- he = &pg->mnthash[MNTHASH];
- for(h = pg->mnthash; h < he; h++){
- for(f = *h; f != nil; f = f->hash){
- print("head: %#p: %s %#llux.%lud %C %lud -> \n", f,
- f->from->path->s, f->from->qid.path,
- f->from->qid.vers, devtab[f->from->type]->dc,
- f->from->dev);
- for(t = f->mount; t != nil; t = t->next)
- print("\t%#p: %s (umh %#p) (path %#.8llux dev %C %lud)\n",
- t, t->to->path->s, t->to->umh, t->to->qid.path, devtab[t->to->type]->dc, t->to->dev);
- }
- }
- poperror();
- runlock(&pg->ns);
-}
-
char*
chanpath(Chan *c)
{
@@ -269,8 +228,6 @@ newchan(void)
return c;
}
-Ref npath;
-
Path*
newpath(char *s)
{
@@ -284,7 +241,6 @@ newpath(char *s)
p->s = smalloc(p->alen);
memmove(p->s, s, i+1);
p->ref = 1;
- incref(&npath);
/*
* Cannot use newpath for arbitrary names because the mtpt
@@ -308,8 +264,6 @@ copypath(Path *p)
pp = smalloc(sizeof(Path));
pp->ref = 1;
- incref(&npath);
- DBG("copypath %s %p => %p\n", p->s, p, pp);
pp->len = p->len;
pp->alen = p->alen;
@@ -332,23 +286,14 @@ void
pathclose(Path *p)
{
int i;
-
- if(p == nil)
- return;
-//XXX
- DBG("pathclose %p %s ref=%ld =>", p, p->s, p->ref);
- for(i=0; i<p->mlen; i++)
- DBG(" %p", p->mtpt[i]);
- DBG("\n");
- if(decref(p))
+ if(p == nil || decref(p))
return;
- decref(&npath);
- free(p->s);
for(i=0; i<p->mlen; i++)
if(p->mtpt[i] != nil)
cclose(p->mtpt[i]);
free(p->mtpt);
+ free(p->s);
free(p);
}
@@ -406,8 +351,9 @@ addelem(Path *p, char *s, Chan *from)
p = uniquepath(p);
i = strlen(s);
- if(p->len+1+i+1 > p->alen){
- a = p->len+1+i+1 + PATHSLOP;
+ a = p->len+1+i+1;
+ if(a > p->alen){
+ a += PATHSLOP;
t = smalloc(a);
memmove(t, p->s, p->len+1);
free(p->s);
@@ -421,7 +367,6 @@ addelem(Path *p, char *s, Chan *from)
p->len += i;
if(isdotdot(s)){
fixdotdotname(p);
- DBG("addelem %s .. => rm %p\n", p->s, p->mtpt[p->mlen-1]);
if(p->mlen > 1 && (c = p->mtpt[--p->mlen]) != nil){
p->mtpt[p->mlen] = nil;
cclose(c);
@@ -434,7 +379,6 @@ addelem(Path *p, char *s, Chan *from)
free(p->mtpt);
p->mtpt = tt;
}
- DBG("addelem %s %s => add %p\n", p->s, s, from);
p->mtpt[p->mlen++] = from;
if(from != nil)
incref(from);
@@ -572,8 +516,6 @@ cclose(Chan *c)
if(c == nil || c->ref < 1 || c->flag&CFREE)
panic("cclose %#p", getcallerpc(&c));
- DBG("cclose %p name=%s ref=%ld\n", c, chanpath(c), c->ref);
-
if(decref(c))
return;
@@ -598,12 +540,8 @@ ccloseq(Chan *c)
if(c == nil || c->ref < 1 || c->flag&CFREE)
panic("ccloseq %#p", getcallerpc(&c));
- DBG("ccloseq %p name=%s ref=%ld\n", c, chanpath(c), c->ref);
-
- if(decref(c))
- return;
-
- closechanq(c);
+ if(decref(c) == 0)
+ closechanq(c);
}
/*
@@ -669,6 +607,35 @@ newmhead(Chan *from)
return mh;
}
+/*
+ * This is necessary because there are many
+ * pointers to the top of a given mount list:
+ *
+ * - the mhead in the namespace hash table
+ * - the mhead in chans returned from findmount:
+ * used in namec and then by unionread.
+ * - the mhead in chans returned from createdir:
+ * used in the open/create race protect, which is gone.
+ *
+ * The RWlock in the Mhead protects the mount list it contains.
+ * The mount list is deleted in cunmount() and closepgrp().
+ * The RWlock ensures that nothing is using the mount list at that time.
+ *
+ * It is okay to replace c->mh with whatever you want as
+ * long as you are sure you have a unique reference to it.
+ *
+ * This comment might belong somewhere else.
+ */
+void
+putmhead(Mhead *m)
+{
+ if(m != nil && decref(m) == 0){
+ assert(m->mount == nil);
+ cclose(m->from);
+ free(m);
+ }
+}
+
int
cmount(Chan **newp, Chan *old, int flag, char *spec)
{
@@ -781,7 +748,6 @@ cmount(Chan **newp, Chan *old, int flag, char *spec)
f->next = m->mount;
m->mount = nm;
}
-
wunlock(&m->lock);
poperror();
return nm->mountid;
@@ -822,35 +788,32 @@ cunmount(Chan *mnt, Chan *mounted)
}
wlock(&m->lock);
+ f = m->mount;
if(mounted == nil){
*l = m->hash;
- wunlock(&pg->ns);
- mountfree(m->mount);
m->mount = nil;
- cclose(m->from);
wunlock(&m->lock);
+ wunlock(&pg->ns);
+ mountfree(f);
putmhead(m);
return;
}
-
- p = &m->mount;
- for(f = *p; f != nil; f = f->next){
- /* BUG: Needs to be 2 pass */
+ for(p = &m->mount; f != nil; f = f->next){
if(eqchan(f->to, mounted, 1) ||
(f->to->mchan != nil && eqchan(f->to->mchan, mounted, 1))){
*p = f->next;
f->next = nil;
- mountfree(f);
if(m->mount == nil){
*l = m->hash;
- cclose(m->from);
wunlock(&m->lock);
wunlock(&pg->ns);
+ mountfree(f);
putmhead(m);
return;
}
wunlock(&m->lock);
wunlock(&pg->ns);
+ mountfree(f);
return;
}
p = &f->next;
@@ -882,36 +845,31 @@ cclone(Chan *c)
int
findmount(Chan **cp, Mhead **mp, int type, int dev, Qid qid)
{
+ Chan *to;
Pgrp *pg;
Mhead *m;
pg = up->pgrp;
rlock(&pg->ns);
for(m = MOUNTH(pg, qid); m != nil; m = m->hash){
- rlock(&m->lock);
- if(m->from == nil){
- print("m %p m->from 0\n", m);
- runlock(&m->lock);
- continue;
- }
if(eqchantdqid(m->from, type, dev, qid, 1)){
+ rlock(&m->lock);
runlock(&pg->ns);
- if(mp != nil){
+ if(mp != nil)
incref(m);
- if(*mp != nil)
- putmhead(*mp);
+ to = m->mount->to;
+ incref(to);
+ runlock(&m->lock);
+ if(mp != nil){
+ putmhead(*mp);
*mp = m;
}
if(*cp != nil)
cclose(*cp);
- incref(m->mount->to);
- *cp = m->mount->to;
- runlock(&m->lock);
+ *cp = to;
return 1;
}
- runlock(&m->lock);
}
-
runlock(&pg->ns);
return 0;
}
@@ -922,7 +880,7 @@ findmount(Chan **cp, Mhead **mp, int type, int dev, Qid qid)
static int
domount(Chan **cp, Mhead **mp, Path **path)
{
- Chan **lc;
+ Chan **lc, *from;
Path *p;
if(findmount(cp, mp, (*cp)->type, (*cp)->dev, (*cp)->qid) == 0)
@@ -934,12 +892,12 @@ domount(Chan **cp, Mhead **mp, Path **path)
if(p->mlen <= 0)
print("domount: path %s has mlen==%d\n", p->s, p->mlen);
else{
+ from = (*mp)->from;
+ incref(from);
lc = &p->mtpt[p->mlen-1];
-DBG("domount %p %s => add %p (was %p)\n", p, p->s, (*mp)->from, p->mtpt[p->mlen-1]);
- incref((*mp)->from);
if(*lc != nil)
cclose(*lc);
- *lc = (*mp)->from;
+ *lc = from;
}
*path = p;
}
@@ -961,7 +919,6 @@ undomount(Chan *c, Path *path)
path->s, path->ref, path->mlen, getcallerpc(&c));
if(path->mlen > 0 && (nc = path->mtpt[path->mlen-1]) != nil){
-DBG("undomount %p %s => remove %p\n", path, path->s, nc);
cclose(c);
path->mtpt[path->mlen-1] = nil;
c = nc;
@@ -1026,8 +983,7 @@ walk(Chan **cp, char **names, int nnames, int nomount, int *nerror)
pathclose(path);
cclose(c);
kstrcpy(up->errstr, Enotdir, ERRMAX);
- if(mh != nil)
- putmhead(mh);
+ putmhead(mh);
return -1;
}
ntry = nnames - nhave;
@@ -1073,8 +1029,7 @@ walk(Chan **cp, char **names, int nnames, int nomount, int *nerror)
pathclose(path);
if(nerror)
*nerror = nhave+1;
- if(mh != nil)
- putmhead(mh);
+ putmhead(mh);
return -1;
}
}
@@ -1113,8 +1068,7 @@ walk(Chan **cp, char **names, int nnames, int nomount, int *nerror)
kstrcpy(up->errstr, Enotdir, ERRMAX);
}
free(wq);
- if(mh != nil)
- putmhead(mh);
+ putmhead(mh);
return -1;
}
n = wq->nqid;
@@ -1140,11 +1094,8 @@ walk(Chan **cp, char **names, int nnames, int nomount, int *nerror)
mh = nmh;
free(wq);
}
-
putmhead(mh);
-
c = cunique(c);
-
if(c->umh != nil){ //BUG
print("walk umh\n");
putmhead(c->umh);
@@ -1176,7 +1127,7 @@ createdir(Chan *c, Mhead *m)
nexterror();
}
for(f = m->mount; f != nil; f = f->next){
- if(f->to != nil && (f->mflag&MCREATE) != 0){
+ if((f->mflag&MCREATE) != 0){
nc = cclone(f->to);
runlock(&m->lock);
poperror();
@@ -1251,15 +1202,6 @@ parsename(char *aname, Elemlist *e)
*slash++ = '\0';
name = slash;
}
-
- if(0 && chandebug){
- int i;
-
- print("parsename %s:", e->name);
- for(i=0; i<=e->nelems; i++)
- print(" %d", e->off[i]);
- print("\n");
- }
}
void*
@@ -1360,7 +1302,6 @@ namec(char *aname, int amode, int omode, ulong perm)
free(aname);
nexterror();
}
- DBG("namec %s %d %d\n", aname, amode, omode);
name = aname;
/*
@@ -1432,8 +1373,6 @@ namec(char *aname, int amode, int omode, ulong perm)
if(e.off[e.nerror]==0)
print("nerror=%d but off=%d\n",
e.nerror, e.off[e.nerror]);
- if(0 && chandebug)
- print("showing %d+%d/%d (of %d) of %s (%d %d)\n", e.prefix, e.off[e.nerror], e.nerror, e.nelems, aname, e.off[0], e.off[1]);
len = e.prefix+e.off[e.nerror];
free(e.off);
namelenerror(aname, len, tmperrbuf);
@@ -1480,8 +1419,7 @@ namec(char *aname, int amode, int omode, ulong perm)
m = nil;
if(!nomount)
domount(&c, &m, nil);
- if(c->umh != nil)
- putmhead(c->umh);
+ putmhead(c->umh);
c->umh = m;
break;
@@ -1519,11 +1457,11 @@ namec(char *aname, int amode, int omode, ulong perm)
case Aopen:
case Acreate:
-if(c->umh != nil){
- print("cunique umh Open\n");
- putmhead(c->umh);
- c->umh = nil;
-}
+ if(c->umh != nil){
+ print("cunique umh Open\n");
+ putmhead(c->umh);
+ c->umh = nil;
+ }
/* only save the mount head if it's a multiple element union */
if(m != nil && m->mount != nil && m->mount->next != nil)
c->umh = m;
@@ -1642,8 +1580,7 @@ if(c->umh != nil){
cnew->flag |= CCEXEC;
if(omode & ORCLOSE)
cnew->flag |= CRCLOSE;
- if(m != nil)
- putmhead(m);
+ putmhead(m);
cclose(c);
c = cnew;
c->path = addelem(c->path, e.elems[e.nelems-1], nil);
@@ -1652,8 +1589,7 @@ if(c->umh != nil){
/* create failed */
cclose(cnew);
- if(m != nil)
- putmhead(m);
+ putmhead(m);
if(omode & OEXCL)
nexterror();
/* save error */
@@ -1788,32 +1724,3 @@ isdir(Chan *c)
return;
error(Enotdir);
}
-
-/*
- * This is necessary because there are many
- * pointers to the top of a given mount list:
- *
- * - the mhead in the namespace hash table
- * - the mhead in chans returned from findmount:
- * used in namec and then by unionread.
- * - the mhead in chans returned from createdir:
- * used in the open/create race protect, which is gone.
- *
- * The RWlock in the Mhead protects the mount list it contains.
- * The mount list is deleted when we cunmount.
- * The RWlock ensures that nothing is using the mount list at that time.
- *
- * It is okay to replace c->mh with whatever you want as
- * long as you are sure you have a unique reference to it.
- *
- * This comment might belong somewhere else.
- */
-void
-putmhead(Mhead *m)
-{
- if(m != nil && decref(m) == 0){
- m->mount = (Mount*)0xCafeBeef;
- free(m);
- }
-}
-
diff --git a/sys/src/9/port/pgrp.c b/sys/src/9/port/pgrp.c
index eb65c8adf..430052db9 100644
--- a/sys/src/9/port/pgrp.c
+++ b/sys/src/9/port/pgrp.c
@@ -67,29 +67,24 @@ closergrp(Rgrp *r)
void
closepgrp(Pgrp *p)
{
- Mhead **h, **e, *f, *next;
+ Mhead **h, **e, *f;
+ Mount *m;
- if(decref(p) != 0)
+ if(decref(p))
return;
- qlock(&p->debug);
- wlock(&p->ns);
- p->pgrpid = -1;
-
e = &p->mnthash[MNTHASH];
for(h = p->mnthash; h < e; h++) {
- for(f = *h; f; f = next) {
+ while((f = *h) != nil){
+ *h = f->hash;
wlock(&f->lock);
- cclose(f->from);
- mountfree(f->mount);
+ m = f->mount;
f->mount = nil;
- next = f->hash;
wunlock(&f->lock);
+ mountfree(m);
putmhead(f);
}
}
- wunlock(&p->ns);
- qunlock(&p->debug);
free(p);
}
@@ -98,12 +93,12 @@ pgrpinsert(Mount **order, Mount *m)
{
Mount *f;
- m->order = 0;
- if(*order == 0) {
+ m->order = nil;
+ if(*order == nil) {
*order = m;
return;
}
- for(f = *order; f; f = f->order) {
+ for(f = *order; f != nil; f = f->order) {
if(m->mountid < f->mountid) {
m->order = f;
*order = m;
@@ -125,17 +120,17 @@ pgrpcpy(Pgrp *to, Pgrp *from)
Mhead *f, **tom, **l, *mh;
wlock(&from->ns);
- order = 0;
+ order = nil;
tom = to->mnthash;
for(i = 0; i < MNTHASH; i++) {
l = tom++;
- for(f = from->mnthash[i]; f; f = f->hash) {
+ for(f = from->mnthash[i]; f != nil; f = f->hash) {
rlock(&f->lock);
mh = newmhead(f->from);
*l = mh;
l = &mh->hash;
link = &mh->mount;
- for(m = f->mount; m; m = m->next) {
+ for(m = f->mount; m != nil; m = m->next) {
n = newmount(mh, m->to, m->mflag, m->spec);
m->copy = n;
pgrpinsert(&order, m);
@@ -148,7 +143,7 @@ pgrpcpy(Pgrp *to, Pgrp *from)
/*
* Allocate mount ids in the same sequence as the parent group
*/
- for(m = order; m; m = m->order)
+ for(m = order; m != nil; m = m->order)
m->copy->mountid = incref(&mountid);
wunlock(&from->ns);
}
@@ -184,7 +179,7 @@ dupfgrp(Fgrp *f)
new->maxfd = f->maxfd;
for(i = 0; i <= f->maxfd; i++) {
- if(c = f->fd[i]){
+ if((c = f->fd[i]) != nil){
incref(c);
new->fd[i] = c;
}
@@ -200,10 +195,7 @@ closefgrp(Fgrp *f)
int i;
Chan *c;
- if(f == 0)
- return;
-
- if(decref(f) != 0)
+ if(f == nil || decref(f))
return;
/*
@@ -212,7 +204,7 @@ closefgrp(Fgrp *f)
*/
up->closingfgrp = f;
for(i = 0; i <= f->maxfd; i++)
- if(c = f->fd[i]){
+ if((c = f->fd[i]) != nil){
f->fd[i] = nil;
cclose(c);
}
@@ -246,7 +238,7 @@ forceclosefgrp(void)
f = up->closingfgrp;
for(i = 0; i <= f->maxfd; i++)
- if(c = f->fd[i]){
+ if((c = f->fd[i]) != nil){
f->fd[i] = nil;
ccloseq(c);
}
@@ -259,12 +251,12 @@ newmount(Mhead *mh, Chan *to, int flag, char *spec)
Mount *m;
m = smalloc(sizeof(Mount));
- m->to = to;
m->head = mh;
+ m->to = to;
incref(to);
m->mountid = incref(&mountid);
m->mflag = flag;
- if(spec != 0)
+ if(spec != nil)
kstrdup(&m->spec, spec);
return m;
@@ -275,28 +267,26 @@ mountfree(Mount *m)
{
Mount *f;
- while(m) {
- f = m->next;
- cclose(m->to);
- m->mountid = 0;
- free(m->spec);
- free(m);
- m = f;
+ while((f = m) != nil) {
+ m = m->next;
+ cclose(f->to);
+ free(f->spec);
+ free(f);
}
}
void
resrcwait(char *reason)
{
+ static ulong lastwhine;
ulong now;
char *p;
- static ulong lastwhine;
- if(up == 0)
+ if(up == nil)
panic("resrcwait");
p = up->psstate;
- if(reason) {
+ if(reason != nil) {
if(waserror()){
up->psstate = p;
nexterror();
@@ -310,7 +300,7 @@ resrcwait(char *reason)
}
}
tsleep(&up->sleep, return0, 0, 100+nrand(200));
- if(reason) {
+ if(reason != nil) {
up->psstate = p;
poperror();
}
diff --git a/sys/src/9/port/portdat.h b/sys/src/9/port/portdat.h
index a5310ecde..9eafd7b93 100644
--- a/sys/src/9/port/portdat.h
+++ b/sys/src/9/port/portdat.h
@@ -476,11 +476,9 @@ struct Image
struct Pgrp
{
Ref;
- Lock;
+ RWlock ns; /* Namespace n read/one write lock */
int noattach;
ulong pgrpid;
- QLock debug; /* single access via devproc.c */
- RWlock ns; /* Namespace n read/one write lock */
Mhead *mnthash[MNTHASH];
};
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-27 02:15:21 +0000