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-rw-r--r--os/port/devsrv.c726
1 files changed, 726 insertions, 0 deletions
diff --git a/os/port/devsrv.c b/os/port/devsrv.c
new file mode 100644
index 00000000..a80a3984
--- /dev/null
+++ b/os/port/devsrv.c
@@ -0,0 +1,726 @@
+#include "u.h"
+#include "../port/lib.h"
+#include "mem.h"
+#include "dat.h"
+#include "fns.h"
+#include "../port/error.h"
+#include "interp.h"
+#include "isa.h"
+#include "runt.h"
+
+typedef struct SrvFile SrvFile;
+struct SrvFile
+{
+ char* spec;
+ char* name;
+ char* user;
+ ulong perm;
+ vlong length;
+ Qid qid;
+ int ref;
+ int opens;
+ int flags;
+ Channel* read;
+ Channel* write;
+ SrvFile* entry;
+ SrvFile* dir;
+ SrvFile* devlist;
+};
+
+enum
+{
+ SORCLOSE = (1<<0),
+ SRDCLOSE = (1<<1),
+ SWRCLOSE = (1<<2),
+ SREMOVED = (1<<3),
+};
+
+typedef struct SrvDev SrvDev;
+struct SrvDev
+{
+ Type* Rread;
+ Type* Rwrite;
+ QLock l;
+ ulong pathgen;
+ SrvFile* devices;
+};
+
+static SrvDev dev;
+
+void freechan(Heap*, int);
+static void freerdchan(Heap*, int);
+static void freewrchan(Heap*, int);
+
+Type *Trdchan;
+Type *Twrchan;
+
+static int
+srvgen(Chan *c, char*, Dirtab*, int, int s, Dir *dp)
+{
+ SrvFile *f;
+
+ if(s == DEVDOTDOT){
+ devdir(c, c->qid, "#s", 0, eve, 0555, dp);
+ return 1;
+ }
+ f = c->aux;
+ if((c->qid.type & QTDIR) == 0){
+ if(s > 0)
+ return -1;
+ devdir(c, f->qid, f->name, f->length, f->user, f->perm, dp);
+ return 1;
+ }
+
+ for(f = f->entry; f != nil; f = f->entry){
+ if(s-- == 0)
+ break;
+ }
+ if(f == nil)
+ return -1;
+
+ devdir(c, f->qid, f->name, f->length, f->user, f->perm, dp);
+ return 1;
+}
+
+static void
+srvinit(void)
+{
+ static uchar rmap[] = Sys_Rread_map;
+ static uchar wmap[] = Sys_Rwrite_map;
+
+ Trdchan = dtype(freerdchan, sizeof(Channel), Tchannel.map, Tchannel.np);
+ Twrchan = dtype(freewrchan, sizeof(Channel), Tchannel.map, Tchannel.np);
+
+ dev.pathgen = 1;
+ dev.Rread = dtype(freeheap, Sys_Rread_size, rmap, sizeof(rmap));
+ dev.Rwrite = dtype(freeheap, Sys_Rwrite_size, wmap, sizeof(wmap));
+}
+
+static int
+srvchkattach(SrvFile *d)
+{
+ if(strcmp(d->user, up->env->user) == 0)
+ return 1;
+
+ /*
+ * Need write permission in other to allow attaches if
+ * we are not the owner
+ */
+ if(d->perm & 2)
+ return 1;
+
+ return 0;
+}
+
+static Chan*
+srvattach(char *spec)
+{
+ Chan *c;
+ SrvFile *d;
+
+ if(spec[0] != '\0'){
+ qlock(&dev.l);
+ for(d = dev.devices; d != nil; d = d->devlist){
+ if(strcmp(spec, d->spec) == 0){
+ if(srvchkattach(d) == 0){
+ qunlock(&dev.l);
+ error(Eperm);
+ }
+ d->ref++;
+ break;
+ }
+ }
+ qunlock(&dev.l);
+
+ if(d != nil){
+ c = devattach('s', spec);
+ c->aux = d;
+ c->qid = d->qid;
+ return c;
+ }
+ }
+
+ d = malloc(sizeof(SrvFile));
+ if(d == nil)
+ error(Enomem);
+
+ c = devattach('s', spec);
+
+ d->ref = 1;
+ kstrdup(&d->spec, spec);
+ kstrdup(&d->user, up->env->user);
+ snprint(up->genbuf, sizeof(up->genbuf), "srv%ld", up->env->pgrp->pgrpid);
+ kstrdup(&d->name, up->genbuf);
+ d->perm = DMDIR|0770;
+
+ qlock(&dev.l);
+ mkqid(&d->qid, dev.pathgen++, 0, QTDIR);
+ d->devlist = dev.devices;
+ dev.devices = d;
+ qunlock(&dev.l);
+
+ c->aux = d;
+ c->qid = d->qid;
+
+ return c;
+}
+
+static Walkqid*
+srvwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+ SrvFile *d, *pd;
+ Walkqid *w;
+
+ pd = c->aux;
+ qlock(&dev.l);
+ if(waserror()){
+ qunlock(&dev.l);
+ nexterror();
+ }
+
+ w = devwalk(c, nc, name, nname, nil, 0, srvgen);
+ if(w != nil && w->clone != nil){
+ if(nname != 0){
+ for(d = pd->entry; d != nil; d = d->entry)
+ if(d->qid.path == w->clone->qid.path)
+ break;
+ if(d == nil)
+ panic("srvwalk");
+ if(w->clone == c)
+ pd->ref--;
+ }else
+ d = pd;
+ w->clone->aux = d;
+ d->ref++;
+ }
+ poperror();
+ qunlock(&dev.l);
+ return w;
+}
+
+static int
+srvstat(Chan *c, uchar *db, int n)
+{
+ qlock(&dev.l);
+ if(waserror()){
+ qunlock(&dev.l);
+ nexterror();
+ }
+ n = devstat(c, db, n, 0, 0, srvgen);
+ poperror();
+ qunlock(&dev.l);
+ return n;
+}
+
+static Chan*
+srvopen(Chan *c, int omode)
+{
+ SrvFile *sf;
+
+ openmode(omode); /* check it */
+ if(c->qid.type & QTDIR){
+ if(omode != OREAD)
+ error(Eisdir);
+ c->mode = omode;
+ c->flag |= COPEN;
+ c->offset = 0;
+ return c;
+ }
+
+ sf = c->aux;
+
+ qlock(&dev.l);
+ if(waserror()){
+ qunlock(&dev.l);
+ nexterror();
+ }
+ devpermcheck(sf->user, sf->perm, omode);
+ if(omode&ORCLOSE && strcmp(sf->user, up->env->user) != 0)
+ error(Eperm);
+ if(sf->perm & DMEXCL && sf->opens != 0)
+ error(Einuse);
+ sf->opens++;
+ if(omode&ORCLOSE)
+ sf->flags |= SORCLOSE;
+ poperror();
+ qunlock(&dev.l);
+
+ c->offset = 0;
+ c->flag |= COPEN;
+ c->mode = openmode(omode);
+
+ return c;
+}
+
+static int
+srvwstat(Chan *c, uchar *dp, int n)
+{
+ Dir *d;
+ SrvFile *sf, *f;
+
+ sf = c->aux;
+ if(strcmp(up->env->user, sf->user) != 0)
+ error(Eperm);
+
+ d = smalloc(sizeof(*d)+n);
+ if(waserror()){
+ free(d);
+ nexterror();
+ }
+ n = convM2D(dp, n, d, (char*)&d[1]);
+ if(n == 0)
+ error(Eshortstat);
+ if(!emptystr(d->name)){
+ if(sf->dir == nil)
+ error(Eperm);
+ validwstatname(d->name);
+ qlock(&dev.l);
+ for(f = sf->dir; f != nil; f = f->entry)
+ if(strcmp(f->name, d->name) == 0){
+ qunlock(&dev.l);
+ error(Eexist);
+ }
+ kstrdup(&sf->name, d->name);
+ qunlock(&dev.l);
+ }
+ if(d->mode != ~0UL)
+ sf->perm = d->mode & (DMEXCL|DMAPPEND|0777);
+ if(d->length != (vlong)-1)
+ sf->length = d->length;
+ poperror();
+ free(d);
+ return n;
+}
+
+static void
+srvputdir(SrvFile *sf)
+{
+ SrvFile **l, *d;
+
+ sf->ref--;
+ if(sf->ref != 0)
+ return;
+
+ for(l = &dev.devices; (d = *l) != nil; l = &d->devlist)
+ if(d == sf){
+ *l = d->devlist;
+ break;
+ }
+ free(sf->spec);
+ free(sf->user);
+ free(sf->name);
+ free(sf);
+}
+
+static void
+srvunblock(SrvFile *sf, int fid)
+{
+ Channel *d;
+ Sys_FileIO_read rreq;
+ Sys_FileIO_write wreq;
+
+ acquire();
+ if(waserror()){
+ release();
+ nexterror();
+ }
+ d = sf->read;
+ if(d != H){
+ rreq.t0 = 0;
+ rreq.t1 = 0;
+ rreq.t2 = fid;
+ rreq.t3 = H;
+ csendalt(d, &rreq, d->mid.t, -1);
+ }
+
+ d = sf->write;
+ if(d != H){
+ wreq.t0 = 0;
+ wreq.t1 = H;
+ wreq.t2 = fid;
+ wreq.t3 = H;
+ csendalt(d, &wreq, d->mid.t, -1);
+ }
+ poperror();
+ release();
+}
+
+static void
+srvdecr(SrvFile *sf, int remove)
+{
+ SrvFile *f, **l;
+
+ if(remove){
+ l = &sf->dir->entry;
+ for(f = *l; f != nil; f = f->entry){
+ if(sf == f){
+ *l = f->entry;
+ break;
+ }
+ l = &f->entry;
+ }
+ sf->ref--;
+ sf->flags |= SREMOVED;
+ }
+
+ if(sf->ref != 0)
+ return;
+
+ if(sf->dir != nil)
+ srvputdir(sf->dir);
+
+ free(sf->spec);
+ free(sf->user);
+ free(sf->name);
+ free(sf);
+}
+
+static void
+srvfree(SrvFile *sf, int flag)
+{
+ sf->flags |= flag;
+ if((sf->flags & (SRDCLOSE | SWRCLOSE)) == (SRDCLOSE | SWRCLOSE)){
+ sf->ref--;
+ srvdecr(sf, (sf->flags & SREMOVED) == 0);
+ }
+}
+
+static void
+freerdchan(Heap *h, int swept)
+{
+ SrvFile *sf;
+
+ release();
+ qlock(&dev.l);
+ sf = H2D(Channel*, h)->aux;
+ sf->read = H;
+ srvfree(sf, SRDCLOSE);
+ qunlock(&dev.l);
+ acquire();
+ freechan(h, swept);
+}
+
+static void
+freewrchan(Heap *h, int swept)
+{
+ SrvFile *sf;
+
+ release();
+ qlock(&dev.l);
+ sf = H2D(Channel*, h)->aux;
+ sf->write = H;
+ srvfree(sf, SWRCLOSE);
+ qunlock(&dev.l);
+ acquire();
+ freechan(h, swept);
+}
+
+static void
+srvclunk(Chan *c, int remove)
+{
+ int opens, noperm;
+ SrvFile *sf;
+
+ sf = c->aux;
+ qlock(&dev.l);
+ if(c->qid.type & QTDIR){
+ srvputdir(sf);
+ qunlock(&dev.l);
+ if(remove)
+ error(Eperm);
+ return;
+ }
+
+ opens = 0;
+ if(c->flag & COPEN){
+ opens = sf->opens--;
+ if (sf->read != H || sf->write != H)
+ srvunblock(sf, c->fid);
+ }
+
+ sf->ref--;
+ if(opens == 1){
+ if((sf->flags & (SORCLOSE | SREMOVED)) == SORCLOSE)
+ remove = 1;
+ }
+
+ noperm = 0;
+ if(remove && strcmp(sf->dir->user, up->env->user) != 0){
+ noperm = 1;
+ remove = 0;
+ }
+
+ srvdecr(sf, remove);
+ qunlock(&dev.l);
+
+ if(noperm)
+ error(Eperm);
+}
+
+static void
+srvclose(Chan *c)
+{
+ srvclunk(c, 0);
+}
+
+static void
+srvremove(Chan *c)
+{
+ srvclunk(c, 1);
+}
+
+static long
+srvread(Chan *c, void *va, long count, vlong offset)
+{
+ int l;
+ Heap * volatile h;
+ Array *a;
+ SrvFile *sp;
+ Channel *rc;
+ Channel *rd;
+ Sys_Rread * volatile r;
+ Sys_FileIO_read req;
+
+ if(c->qid.type & QTDIR){
+ qlock(&dev.l);
+ if(waserror()){
+ qunlock(&dev.l);
+ nexterror();
+ }
+ l = devdirread(c, va, count, 0, 0, srvgen);
+ poperror();
+ qunlock(&dev.l);
+ return l;
+ }
+
+ sp = c->aux;
+
+ acquire();
+ if(waserror()){
+ release();
+ nexterror();
+ }
+
+ rd = sp->read;
+ if(rd == H)
+ error(Eshutdown);
+
+ rc = cnewc(dev.Rread, movtmp, 1);
+ ptradd(D2H(rc));
+ if(waserror()){
+ ptrdel(D2H(rc));
+ destroy(rc);
+ nexterror();
+ }
+
+ req.t0 = offset;
+ req.t1 = count;
+ req.t2 = c->fid;
+ req.t3 = rc;
+ csend(rd, &req);
+
+ h = heap(dev.Rread);
+ r = H2D(Sys_Rread *, h);
+ ptradd(h);
+ if(waserror()){
+ ptrdel(h);
+ destroy(r);
+ nexterror();
+ }
+
+ crecv(rc, r);
+ if(r->t1 != H)
+ error(string2c(r->t1));
+
+ a = r->t0;
+ l = 0;
+ if(a != H){
+ l = a->len;
+ if(l > count)
+ l = count;
+ memmove(va, a->data, l);
+ }
+
+ poperror();
+ ptrdel(h);
+ destroy(r);
+
+ poperror();
+ ptrdel(D2H(rc));
+ destroy(rc);
+
+ poperror();
+ release();
+
+ return l;
+}
+
+static long
+srvwrite(Chan *c, void *va, long count, vlong offset)
+{
+ long l;
+ Heap * volatile h;
+ SrvFile *sp;
+ Channel *wc;
+ Channel *wr;
+ Sys_Rwrite * volatile w;
+ Sys_FileIO_write req;
+
+ if(c->qid.type & QTDIR)
+ error(Eperm);
+
+ acquire();
+ if(waserror()){
+ release();
+ nexterror();
+ }
+
+ sp = c->aux;
+ wr = sp->write;
+ if(wr == H)
+ error(Eshutdown);
+
+ wc = cnewc(dev.Rwrite, movtmp, 1);
+ ptradd(D2H(wc));
+ if(waserror()){
+ ptrdel(D2H(wc));
+ destroy(wc);
+ nexterror();
+ }
+
+ req.t0 = offset;
+ req.t1 = mem2array(va, count);
+ req.t2 = c->fid;
+ req.t3 = wc;
+
+ ptradd(D2H(req.t1));
+ if(waserror()){
+ ptrdel(D2H(req.t1));
+ destroy(req.t1);
+ nexterror();
+ }
+
+ csend(wr, &req);
+
+ poperror();
+ ptrdel(D2H(req.t1));
+ destroy(req.t1);
+
+ poperror();
+ ptrdel(D2H(wc));
+ destroy(wc);
+
+ h = heap(dev.Rwrite);
+ w = H2D(Sys_Rwrite *, h);
+ ptradd(h);
+ if(waserror()){
+ ptrdel(h);
+ destroy(w);
+ nexterror();
+ }
+ crecv(wc, w);
+ if(w->t1 != H)
+ error(string2c(w->t1));
+ poperror();
+ ptrdel(h);
+ l = w->t0;
+ destroy(w);
+
+ poperror();
+ release();
+ if(l < 0)
+ l = 0;
+ return l;
+}
+
+static void
+srvretype(Channel *c, SrvFile *f, Type *t)
+{
+ Heap *h;
+
+ h = D2H(c);
+ h->t->ref--;
+ h->t = t;
+ t->ref++;
+ c->aux = f;
+}
+
+int
+srvf2c(char *dir, char *file, Sys_FileIO *io)
+{
+ SrvFile *s, *f;
+ volatile struct { Chan *c; } c;
+
+ c.c = nil;
+ if(waserror()){
+ cclose(c.c);
+ return -1;
+ }
+
+ if(strchr(file, '/') != nil || strlen(file) >= 64 || strcmp(file, ".") == 0 || strcmp(file, "..") == 0)
+ error(Efilename);
+
+ c.c = namec(dir, Aaccess, 0, 0);
+ if((c.c->qid.type&QTDIR) == 0 || devtab[c.c->type]->dc != 's')
+ error("directory not a srv device");
+
+ s = c.c->aux;
+
+ qlock(&dev.l);
+ for(f = s->entry; f != nil; f = f->entry){
+ if(strcmp(f->name, file) == 0){
+ qunlock(&dev.l);
+ error(Eexist);
+ }
+ }
+
+ f = malloc(sizeof(SrvFile));
+ if(f == nil){
+ qunlock(&dev.l);
+ error(Enomem);
+ }
+
+ srvretype(io->read, f, Trdchan);
+ srvretype(io->write, f, Twrchan);
+ f->read = io->read;
+ f->write = io->write;
+
+ kstrdup(&f->name, file);
+ kstrdup(&f->user, up->env->user);
+ f->perm = 0666 & (~0666 | (s->perm & 0666));
+ f->length = 0;
+ f->ref = 2;
+ mkqid(&f->qid, dev.pathgen++, 0, QTFILE);
+
+ f->entry = s->entry;
+ s->entry = f;
+ s->ref++;
+ f->dir = s;
+ qunlock(&dev.l);
+
+ cclose(c.c);
+ poperror();
+
+ return 0;
+}
+
+Dev srvdevtab = {
+ 's',
+ "srv",
+
+ devreset,
+ srvinit,
+ devshutdown,
+ srvattach,
+ srvwalk,
+ srvstat,
+ srvopen,
+ devcreate,
+ srvclose,
+ srvread,
+ devbread,
+ srvwrite,
+ devbwrite,
+ srvremove,
+ srvwstat
+};
generated by cgit v1.2.3 (git 2.46.0) at 2025-12-10 10:13:51 +0000