cap: Fix openmode issue
[akaros.git] / kern / drivers / dev / proc.c
index b5c39d5..ea35586 100644 (file)
@@ -43,18 +43,21 @@ enum {
        Qdir,
        Qtrace,
        Qtracepids,
+       Qself,
        Qns,
        Qargs,
        Qctl,
        Qfd,
        Qfpregs,
        Qkregs,
+       Qmaps,
        Qmem,
        Qnote,
        Qnoteid,
        Qnotepg,
        Qproc,
        Qregs,
+       Quser,
        Qsegment,
        Qstatus,
        Qstrace,
@@ -81,7 +84,6 @@ enum {
        CMstartstop,
        CMstartsyscall,
        CMstop,
-       CMtrace,
        CMwaitstop,
        CMwired,
        CMcore,
@@ -111,6 +113,7 @@ struct dirtab procdir[] = {
        {"fd", {Qfd}, 0, 0444},
        {"fpregs", {Qfpregs}, 0, 0000},
        //  {"kregs",   {Qkregs},   sizeof(Ureg),       0600},
+       {"maps", {Qmaps}, 0, 0000},
        {"mem", {Qmem}, 0, 0000},
        {"note", {Qnote}, 0, 0000},
        {"noteid", {Qnoteid}, 0, 0664},
@@ -118,6 +121,7 @@ struct dirtab procdir[] = {
        {"ns", {Qns}, 0, 0444},
        {"proc", {Qproc}, 0, 0400},
        //  {"regs",        {Qregs},    sizeof(Ureg),       0000},
+       {"user", {Quser}, 0, 0444},
        {"segment", {Qsegment}, 0, 0444},
        {"status", {Qstatus}, STATSIZE, 0444},
        {"strace", {Qstrace}, 0, 0666},
@@ -145,7 +149,6 @@ struct cmdtab proccmd[] = {
        {CMstartstop, "startstop", 1},
        {CMstartsyscall, "startsyscall", 1},
        {CMstop, "stop", 1},
-       {CMtrace, "trace", 0},
        {CMwaitstop, "waitstop", 1},
        {CMwired, "wired", 2},
        {CMcore, "core", 2},
@@ -221,7 +224,7 @@ procgen(struct chan *c, char *name, struct dirtab *tab, int unused, int s,
        uint32_t path, perm, len;
        if (s == DEVDOTDOT) {
                mkqid(&qid, Qdir, 0, QTDIR);
-               devdir(c, qid, devname(), 0, eve, 0555, dp);
+               devdir(c, qid, devname(), 0, eve.name, 0555, dp);
                return 1;
        }
 
@@ -229,16 +232,23 @@ procgen(struct chan *c, char *name, struct dirtab *tab, int unused, int s,
                if (s == 0) {
                        strlcpy(get_cur_genbuf(), "trace", GENBUF_SZ);
                        mkqid(&qid, Qtrace, -1, QTFILE);
-                       devdir(c, qid, get_cur_genbuf(), 0, eve, 0444, dp);
+                       devdir(c, qid, get_cur_genbuf(), 0, eve.name, 0444, dp);
                        return 1;
                }
                if (s == 1) {
                        strlcpy(get_cur_genbuf(), "tracepids", GENBUF_SZ);
                        mkqid(&qid, Qtracepids, -1, QTFILE);
-                       devdir(c, qid, get_cur_genbuf(), 0, eve, 0444, dp);
+                       devdir(c, qid, get_cur_genbuf(), 0, eve.name, 0444, dp);
                        return 1;
                }
-               s -= 2;
+               if (s == 2) {
+                       p = current;
+                       strlcpy(get_cur_genbuf(), "self", GENBUF_SZ);
+                       mkqid(&qid, (p->pid + 1) << QSHIFT, p->pid, QTDIR);
+                       devdir(c, qid, get_cur_genbuf(), 0, p->user.name, DMDIR | 0555, dp);
+                       return 1;
+               }
+               s -= 3;
                if (name != NULL) {
                        /* ignore s and use name to find pid */
                        pid = strtol(name, &ename, 10);
@@ -266,24 +276,24 @@ procgen(struct chan *c, char *name, struct dirtab *tab, int unused, int s,
                 */
                if (name != NULL && strcmp(name, get_cur_genbuf()) != 0) {
                        printk("pid-name mismatch, name: %s, pid %d\n", name, pid);
-                       kref_put(&p->p_kref);
+                       proc_decref(p);
                        return -1;
                }
                mkqid(&qid, (s + 1) << QSHIFT, pid, QTDIR);
-               devdir(c, qid, get_cur_genbuf(), 0, p->user, DMDIR | 0555, dp);
-               kref_put(&p->p_kref);
+               devdir(c, qid, get_cur_genbuf(), 0, p->user.name, DMDIR | 0555, dp);
+               proc_decref(p);
                return 1;
        }
        if (c->qid.path == Qtrace) {
                strlcpy(get_cur_genbuf(), "trace", GENBUF_SZ);
                mkqid(&qid, Qtrace, -1, QTFILE);
-               devdir(c, qid, get_cur_genbuf(), 0, eve, 0444, dp);
+               devdir(c, qid, get_cur_genbuf(), 0, eve.name, 0444, dp);
                return 1;
        }
        if (c->qid.path == Qtracepids) {
                strlcpy(get_cur_genbuf(), "tracepids", GENBUF_SZ);
                mkqid(&qid, Qtracepids, -1, QTFILE);
-               devdir(c, qid, get_cur_genbuf(), 0, eve, 0444, dp);
+               devdir(c, qid, get_cur_genbuf(), 0, eve.name, 0444, dp);
                return 1;
        }
        if (s >= ARRAY_SIZE(procdir))
@@ -322,8 +332,8 @@ procgen(struct chan *c, char *name, struct dirtab *tab, int unused, int s,
 #endif
 
        mkqid(&qid, path | tab->qid.path, c->qid.vers, QTFILE);
-       devdir(c, qid, tab->name, len, p->user, perm, dp);
-       kref_put(&p->p_kref);
+       devdir(c, qid, tab->name, len, p->user.name, perm, dp);
+       proc_decref(p);
        return 1;
 }
 
@@ -405,7 +415,7 @@ static void nonone(struct proc *p)
 #if 0
        if (p == up)
                return;
-       if (strcmp(current->user, "none") != 0)
+       if (strcmp(current->user.name, "none") != 0)
                return;
        if (iseve())
                return;
@@ -413,6 +423,72 @@ static void nonone(struct proc *p)
 #endif
 }
 
+struct bm_helper {
+       void                                            *buf;
+       size_t                                          buflen;
+       size_t                                          sofar;
+};
+
+static void get_needed_sz_cb(struct vm_region *vmr, void *arg)
+{
+       struct bm_helper *bmh = (struct bm_helper*)arg;
+
+       /* ballpark estimate of a line */
+       bmh->buflen += 150;
+}
+
+static void build_maps_cb(struct vm_region *vmr, void *arg)
+{
+       struct bm_helper *bmh = (struct bm_helper*)arg;
+       size_t old_sofar;
+       char path_buf[MAX_FILENAME_SZ];
+       char *path;
+       unsigned long inode_nr;
+
+       if (vmr->vm_file) {
+               path = file_abs_path(vmr->vm_file, path_buf, sizeof(path_buf));
+               inode_nr = vmr->vm_file->f_dentry->d_inode->i_ino;
+       } else {
+               strlcpy(path_buf, "[heap]", sizeof(path_buf));
+               path = path_buf;
+               inode_nr = 0;
+       }
+
+       old_sofar = bmh->sofar;
+       bmh->sofar += snprintf(bmh->buf + bmh->sofar, bmh->buflen - bmh->sofar,
+                              "%08lx-%08lx %c%c%c%c %08x %02d:%02d %d ",
+                              vmr->vm_base, vmr->vm_end,
+                              vmr->vm_prot & PROT_READ    ? 'r' : '-',
+                              vmr->vm_prot & PROT_WRITE   ? 'w' : '-',
+                              vmr->vm_prot & PROT_EXEC    ? 'x' : '-',
+                              vmr->vm_flags & MAP_PRIVATE ? 'p' : '-',
+                              vmr->vm_file ? vmr->vm_foff : 0,
+                              vmr->vm_file ? 1 : 0,    /* VFS == 1 for major */
+                              0,
+                              inode_nr);
+       /* Align the filename to the 74th char, like Linux (73 chars so far) */
+       bmh->sofar += snprintf(bmh->buf + bmh->sofar, bmh->buflen - bmh->sofar,
+                              "%*s", 73 - (bmh->sofar - old_sofar), "");
+       bmh->sofar += snprintf(bmh->buf + bmh->sofar, bmh->buflen - bmh->sofar,
+                              "%s\n", path);
+}
+
+static struct sized_alloc *build_maps(struct proc *p)
+{
+       struct bm_helper bmh[1];
+       struct sized_alloc *sza;
+
+       /* Try to figure out the size needed: start with extra space, then add a bit
+        * for each VMR */
+       bmh->buflen = 150;
+       enumerate_vmrs(p, get_needed_sz_cb, bmh);
+       sza = sized_kzmalloc(bmh->buflen, MEM_WAIT);
+       bmh->buf = sza->buf;
+       bmh->sofar = 0;
+       enumerate_vmrs(p, build_maps_cb, bmh);
+       return sza;
+}
+
 static struct chan *procopen(struct chan *c, int omode)
 {
        ERRSTACK(2);
@@ -439,10 +515,10 @@ static struct chan *procopen(struct chan *c, int omode)
                topens++;
                if (tevents == NULL) {
                        tevents = (Traceevent *) kzmalloc(sizeof(Traceevent) * Nevents,
-                                                                                         KMALLOC_WAIT);
+                                                                                         MEM_WAIT);
                        if (tevents == NULL)
                                error(ENOMEM, ERROR_FIXME);
-                       tpids = kzmalloc(Ntracedpids * 20, KMALLOC_WAIT);
+                       tpids = kzmalloc(Ntracedpids * 20, MEM_WAIT);
                        if (tpids == NULL) {
                                kfree(tpids);
                                tpids = NULL;
@@ -479,7 +555,7 @@ static struct chan *procopen(struct chan *c, int omode)
        //qlock(&p->debug);
        if (waserror()) {
                //qunlock(&p->debug);
-               kref_put(&p->p_kref);
+               proc_decref(p);
                nexterror();
        }
        pid = PID(c->qid);
@@ -498,7 +574,7 @@ static struct chan *procopen(struct chan *c, int omode)
                        tc->offset = 0;
                        poperror();
                        qunlock(&p->debug);
-                       kref_put(&p->p_kref);
+                       proc_decref(p);
                        cclose(c);
                        return tc;
 */
@@ -535,8 +611,9 @@ static struct chan *procopen(struct chan *c, int omode)
                case Qns:
                        if (omode != O_READ)
                                error(EPERM, ERROR_FIXME);
-                       c->aux = kzmalloc(sizeof(struct mntwalk), KMALLOC_WAIT);
+                       c->aux = kzmalloc(sizeof(struct mntwalk), MEM_WAIT);
                        break;
+               case Quser:
                case Qstatus:
                case Qvmstatus:
                case Qctl:
@@ -551,6 +628,9 @@ static struct chan *procopen(struct chan *c, int omode)
                        kref_get(&p->strace->users, 1);
                        c->aux = p->strace;
                        break;
+               case Qmaps:
+                       c->aux = build_maps(p);
+                       break;
                case Qnotepg:
                        error(ENOSYS, ERROR_FIXME);
 #if 0
@@ -583,7 +663,7 @@ static struct chan *procopen(struct chan *c, int omode)
        tc = devopen(c, omode, 0, 0, procgen);
        poperror();
        //qunlock(&p->debug);
-       kref_put(&p->p_kref);
+       proc_decref(p);
        return tc;
 }
 
@@ -608,7 +688,7 @@ static int procwstat(struct chan *c, uint8_t * db, int n)
        qlock(&p->debug);
        if (waserror()) {
                qunlock(&p->debug);
-               kref_put(&p->p_kref);
+               proc_decref(p);
                kfree(d);
                nexterror();
        }
@@ -616,25 +696,25 @@ static int procwstat(struct chan *c, uint8_t * db, int n)
        if (p->pid != PID(c->qid))
                error(ESRCH, ERROR_FIXME);
 
-       if (strcmp(current->user, p->user) != 0 && strcmp(current->user, eve) != 0)
+       if (strcmp(current->user.name, p->user.name) != 0 && !iseve())
                error(EPERM, ERROR_FIXME);
 
-       d = kzmalloc(sizeof(struct dir) + n, KMALLOC_WAIT);
+       d = kzmalloc(sizeof(struct dir) + n, MEM_WAIT);
        n = convM2D(db, n, &d[0], (char *)&d[1]);
        if (n == 0)
                error(ENOENT, ERROR_FIXME);
-       if (!emptystr(d->uid) && strcmp(d->uid, p->user) != 0) {
-               if (strcmp(current->user, eve) != 0)
+       if (!emptystr(d->uid) && strcmp(d->uid, p->user.name) != 0) {
+               if (!iseve())
                        error(EPERM, ERROR_FIXME);
                else
-                       kstrdup(&p->user, d->uid);
+                       proc_set_username(p, d->uid);
        }
        if (d->mode != ~0UL)
                p->procmode = d->mode & 0777;
 
        poperror();
        qunlock(&p->debug);
-       kref_put(&p->p_kref);
+       proc_decref(p);
        kfree(d);
 
        return n;
@@ -752,6 +832,8 @@ static void procclose(struct chan *c)
        }
        if (QID(c->qid) == Qns && c->aux != 0)
                kfree(c->aux);
+       if (QID(c->qid) == Qmaps && c->aux != 0)
+               kfree(c->aux);
        if (QID(c->qid) == Qstrace && c->aux != 0) {
                struct strace *s = c->aux;
 
@@ -788,11 +870,11 @@ static char *argcpy(char *s, char *p)
        if (n > 128)
                n = 128;
        if (n <= 0) {
-               t = kzmalloc(1, KMALLOC_WAIT);
+               t = kzmalloc(1, MEM_WAIT);
                *t = 0;
                return t;
        }
-       t = kzmalloc(n, KMALLOC_WAIT);
+       t = kzmalloc(n, MEM_WAIT);
        tp = t;
        te = t + n;
 
@@ -826,18 +908,20 @@ static int eventsavailable(void *)
        return tproduced > tconsumed;
 }
 #endif
+
 static long procread(struct chan *c, void *va, long n, int64_t off)
 {
-       ERRSTACK(5);
+       ERRSTACK(1);
        struct proc *p;
        long l, r;
        int i, j, navail, pid, rsize;
-       char flag[10], *sps, *srv, statbuf[512];
+       char flag[10], *sps, *srv;
        uintptr_t offset, u;
        int tesz;
        uint8_t *rptr;
        struct mntwalk *mw;
        struct strace *s;
+       struct sized_alloc *sza;
 
        if (c->qid.type & QTDIR) {
                int nn;
@@ -848,328 +932,38 @@ static long procread(struct chan *c, void *va, long n, int64_t off)
        }
 
        offset = off;
-#if 0
-       if (QID(c->qid) == Qtrace) {
-               if (!eventsavailable(NULL))
-                       return 0;
-
-               rptr = va;
-               tesz = BIT32SZ + BIT32SZ + BIT64SZ + BIT32SZ;
-               navail = tproduced - tconsumed;
-               if (navail > n / tesz)
-                       navail = n / tesz;
-               while (navail > 0) {
-                       PBIT32(rptr, tevents[tconsumed & Emask].pid);
-                       rptr += BIT32SZ;
-                       PBIT32(rptr, tevents[tconsumed & Emask].etype);
-                       rptr += BIT32SZ;
-                       PBIT64(rptr, tevents[tconsumed & Emask].time);
-                       rptr += BIT64SZ;
-                       PBIT32(rptr, tevents[tconsumed & Emask].core);
-                       rptr += BIT32SZ;
-                       tconsumed++;
-                       navail--;
-               }
-               return rptr - (uint8_t *) va;
+       /* Some shit in proc doesn't need to grab the reference.  For strace, we
+        * already have the chan open, and all we want to do is read the queue,
+        * which exists because of our kref on it. */
+       switch (QID(c->qid)) {
+               case Qstrace:
+                       s = c->aux;
+                       n = qread(s->q, va, n);
+                       return n;
        }
 
-       if (QID(c->qid) == Qtracepids)
-               if (tpids == NULL)
-                       return 0;
-               else
-                       return readstr(off, va, n, tpids);
-#endif
        if ((p = pid2proc(SLOT(c->qid))) == NULL)
                error(ESRCH, "%d: no such process", SLOT(c->qid));
        if (p->pid != PID(c->qid)) {
-               kref_put(&p->p_kref);
+               proc_decref(p);
                error(ESRCH, "weird: p->pid is %d, PID(c->qid) is %d: mismatch",
                      p->pid, PID(c->qid));
        }
        switch (QID(c->qid)) {
                default:
-                       kref_put(&p->p_kref);
+                       proc_decref(p);
                        break;
-#if 0
-#warning check refcnting in here
-               case Qargs:
-                       qlock(&p->debug);
-                       j = procargs(p, current->genbuf, sizeof current->genbuf);
-                       qunlock(&p->debug);
-                       kref_put(&p->p_kref);
-                       if (offset >= j)
-                               return 0;
-                       if (offset + n > j)
-                               n = j - offset;
-                       memmove(va, &current->genbuf[offset], n);
-                       return n;
-
-               case Qsyscall:
-                       if (p->syscalltrace == NULL)
-                               return 0;
-                       return readstr(offset, va, n, p->syscalltrace);
-
-               case Qcore:
-                       i = 0;
-                       ac = p->ac;
-                       wired = p->wired;
-                       if (ac != NULL)
-                               i = ac->machno;
-                       else if (wired != NULL)
-                               i = wired->machno;
-                       snprint(statbuf, sizeof statbuf, "%d\n", i);
-                       return readstr(offset, va, n, statbuf);
-
-               case Qmem:
-                       if (offset < KZERO
-                               || (offset >= USTKTOP - USTKSIZE && offset < USTKTOP)) {
-                               r = procctlmemio(p, offset, n, va, 1);
-                               kref_put(&p->p_kref);
-                               return r;
-                       }
-
-                       if (!iseve()) {
-                               kref_put(&p->p_kref);
-                               error(EPERM, ERROR_FIXME);
-                       }
-
-                       /* validate kernel addresses */
-                       if (offset < PTR2UINT(end)) {
-                               if (offset + n > PTR2UINT(end))
-                                       n = PTR2UINT(end) - offset;
-                               memmove(va, UINT2PTR(offset), n);
-                               kref_put(&p->p_kref);
-                               return n;
-                       }
-                       for (i = 0; i < nelem(conf.mem); i++) {
-                               cm = &conf.mem[i];
-                               /* klimit-1 because klimit might be zero! */
-                               if (cm->kbase <= offset && offset <= cm->klimit - 1) {
-                                       if (offset + n >= cm->klimit - 1)
-                                               n = cm->klimit - offset;
-                                       memmove(va, UINT2PTR(offset), n);
-                                       kref_put(&p->p_kref);
-                                       return n;
-                               }
-                       }
-                       kref_put(&p->p_kref);
-                       error(EINVAL, ERROR_FIXME);
-
-               case Qprofile:
-                       s = p->seg[TSEG];
-                       if (s == 0 || s->profile == 0)
-                               error(EFAIL, "profile is off");
-                       i = (s->top - s->base) >> LRESPROF;
-                       i *= sizeof(*s->profile);
-                       if (offset >= i) {
-                               kref_put(&p->p_kref);
-                               return 0;
-                       }
-                       if (offset + n > i)
-                               n = i - offset;
-                       memmove(va, ((char *)s->profile) + offset, n);
-                       kref_put(&p->p_kref);
-                       return n;
-
-               case Qnote:
-                       qlock(&p->debug);
-                       if (waserror()) {
-                               qunlock(&p->debug);
-                               kref_put(&p->p_kref);
-                               nexterror();
-                       }
-                       if (p->pid != PID(c->qid))
-                               error(ESRCH, ERROR_FIXME);
-                       if (n < 1)      /* must accept at least the '\0' */
-                               error(ENAMETOOLONG, ERROR_FIXME);
-                       if (p->nnote == 0)
-                               n = 0;
-                       else {
-                               i = strlen(p->note[0].msg) + 1;
-                               if (i > n)
-                                       i = n;
-                               rptr = va;
-                               memmove(rptr, p->note[0].msg, i);
-                               rptr[i - 1] = '\0';
-                               p->nnote--;
-                               memmove(p->note, p->note + 1, p->nnote * sizeof(Note));
-                               n = i;
-                       }
-                       if (p->nnote == 0)
-                               p->notepending = 0;
-                       poperror();
-                       qunlock(&p->debug);
-                       kref_put(&p->p_kref);
-                       return n;
-
-               case Qproc:
-                       if (offset >= sizeof(struct proc)) {
-                               kref_put(&p->p_kref);
-                               return 0;
-                       }
-                       if (offset + n > sizeof(struct proc))
-                               n = sizeof(struct proc) - offset;
-                       memmove(va, ((char *)p) + offset, n);
-                       kref_put(&p->p_kref);
-                       return n;
-
-               case Qregs:
-                       rptr = (uint8_t *) p->dbgreg;
-                       rsize = sizeof(Ureg);
-regread:
-                       if (rptr == 0) {
-                               kref_put(&p->p_kref);
-                               error(ENODATA, ERROR_FIXME);
-                       }
-                       if (offset >= rsize) {
-                               kref_put(&p->p_kref);
-                               return 0;
-                       }
-                       if (offset + n > rsize)
-                               n = rsize - offset;
-                       memmove(va, rptr + offset, n);
-                       kref_put(&p->p_kref);
-                       return n;
-
-               case Qkregs:
-                       memset(&kur, 0, sizeof(Ureg));
-                       setkernur(&kur, p);
-                       rptr = (uint8_t *) & kur;
-                       rsize = sizeof(Ureg);
-                       goto regread;
-
-               case Qfpregs:
-                       r = fpudevprocio(p, va, n, offset, 0);
-                       kref_put(&p->p_kref);
-                       return r;
-
-               case Qstatus:
-                       if (offset >= STATSIZE) {
-                               kref_put(&p->p_kref);
-                               return 0;
-                       }
-                       if (offset + n > STATSIZE)
-                               n = STATSIZE - offset;
-
-                       sps = p->psstate;
-                       if (sps == 0)
-                               sps = statename[p->state];
-                       memset(statbuf, ' ', sizeof statbuf);
-                       j = 2 * KNAMELEN + 12;
-                       snprint(statbuf, j + 1, "%-*.*s%-*.*s%-12.11s",
-                                       KNAMELEN, KNAMELEN - 1, p->text,
-                                       KNAMELEN, KNAMELEN - 1, p->user, sps);
-
-                       for (i = 0; i < 6; i++) {
-                               l = p->time[i];
-                               if (i == TReal)
-                                       l = sys->ticks - l;
-                               l = TK2MS(l);
-                               readnum(0, statbuf + j + NUMSIZE * i, NUMSIZE, l, NUMSIZE);
-                       }
-                       /* ignore stack, which is mostly non-existent */
-                       u = 0;
-                       for (i = 1; i < NSEG; i++) {
-                               s = p->seg[i];
-                               if (s)
-                                       u += s->top - s->base;
-                       }
-                       readnum(0, statbuf + j + NUMSIZE * 6, NUMSIZE, u >> 10u, NUMSIZE);      /* wrong size */
-                       readnum(0, statbuf + j + NUMSIZE * 7, NUMSIZE, p->basepri, NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 8, NUMSIZE, p->priority,
-                                       NUMSIZE);
-
-                       /*
-                        * NIX: added # of traps, syscalls, and iccs
-                        */
-                       readnum(0, statbuf + j + NUMSIZE * 9, NUMSIZE, p->ntrap, NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 10, NUMSIZE, p->nintr, NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 11, NUMSIZE, p->nsyscall,
-                                       NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 12, NUMSIZE, p->nicc, NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 13, NUMSIZE, p->nactrap,
-                                       NUMSIZE);
-                       readnum(0, statbuf + j + NUMSIZE * 14, NUMSIZE, p->nacsyscall,
-                                       NUMSIZE);
-                       memmove(va, statbuf + offset, n);
-                       kref_put(&p->p_kref);
-                       return n;
-
-               case Qsegment:
-                       j = 0;
-                       for (i = 0; i < NSEG; i++) {
-                               sg = p->seg[i];
-                               if (sg == 0)
-                                       continue;
-                               j += sprint(statbuf + j, "%-6s %c%c %p %p %4d\n",
-                                                       sname[sg->type & SG_TYPE],
-                                                       sg->type & SG_RONLY ? 'R' : ' ',
-                                                       sg->profile ? 'P' : ' ',
-                                                       sg->base, sg->top, sg->ref);
-                       }
-                       kref_put(&p->p_kref);
-                       if (offset >= j)
-                               return 0;
-                       if (offset + n > j)
-                               n = j - offset;
-                       if (n == 0 && offset == 0)
-                               exhausted("segments");
-                       memmove(va, &statbuf[offset], n);
-                       return n;
-
-               case Qwait:
-                       if (!canqlock(&p->qwaitr)) {
-                               kref_put(&p->p_kref);
-                               error(EBUSY, ERROR_FIXME);
-                       }
-
-                       if (waserror()) {
-                               qunlock(&p->qwaitr);
-                               kref_put(&p->p_kref);
-                               nexterror();
-                       }
+               case Quser: {
+                               int i;
 
-                       lock(&p->exl);
-                       if (up == p && p->nchild == 0 && p->waitq == 0) {
-                               unlock(&p->exl);
-                               error(ECHILD, ERROR_FIXME);
-                       }
-                       pid = p->pid;
-                       while (p->waitq == 0) {
-                               unlock(&p->exl);
-                               rendez_sleep(&p->waitr, haswaitq, p);
-                               if (p->pid != pid)
-                                       error(ESRCH, ERROR_FIXME);
-                               lock(&p->exl);
+                               i = readstr(off, va, n, p->user.name);
+                               proc_decref(p);
+                               return i;
                        }
-                       wq = p->waitq;
-                       p->waitq = wq->next;
-                       p->nwait--;
-                       unlock(&p->exl);
-
-                       poperror();
-                       qunlock(&p->qwaitr);
-                       kref_put(&p->p_kref);
-                       n = snprint(va, n, "%d %lu %lud %lud %q",
-                                               wq->w.pid,
-                                               wq->w.time[TUser], wq->w.time[TSys], wq->w.time[TReal],
-                                               wq->w.msg);
-                       kfree(wq);
-                       return n;
-#endif
-               case Qstrace:
-                       s = c->aux;
-                       /* We need to decref, so that p can get freed while we are blocked
-                        * on the qread.  in proc_free, the strace is released that will
-                        * qhangup that will wake us up. */
-                       kref_put(&p->p_kref);
-                       n = qread(s->q, va, n);
-                       return n;
-
                case Qstatus:{
                                /* the old code grew the stack and was hideous.
                                 * status is not a high frequency operation; just malloc. */
-                               char *buf = kmalloc(4096, KMALLOC_WAIT);
+                               char *buf = kmalloc(4096, MEM_WAIT);
                                char *s = buf, *e = buf + 4096;
                                int i;
 
@@ -1181,7 +975,7 @@ regread:
                                        s = seprintf(s, e, " %d trace users %d traced procs",
                                                     kref_refcnt(&p->strace->users),
                                                     kref_refcnt(&p->strace->procs));
-                               kref_put(&p->p_kref);
+                               proc_decref(p);
                                i = readstr(off, va, n, buf);
                                kfree(buf);
                                return i;
@@ -1189,27 +983,30 @@ regread:
 
                case Qvmstatus:
                        {
-                               char buf[50*65 + 2];
+                               size_t buflen = 50 * 65 + 2;
+                               char *buf = kmalloc(buflen, MEM_WAIT);
                                int i, offset;
-                               offset=0;
-                               offset += snprintf(buf+offset, sizeof(buf)-offset, "{\n");
+                               offset = 0;
+                               offset += snprintf(buf + offset, buflen - offset, "{\n");
                                for (i = 0; i < 65; i++) {
                                        if (p->vmm.vmexits[i] != 0) {
-                                               offset += snprintf(buf+offset, sizeof(buf)-offset,
+                                               offset += snprintf(buf + offset, buflen - offset,
                                                                   "\"%s\":\"%lld\",\n",
                                                                   VMX_EXIT_REASON_NAMES[i],
                                                                   p->vmm.vmexits[i]);
                                        }
                                }
-                               offset += snprintf(buf+offset, sizeof(buf)-offset, "}\n");
-                               kref_put(&p->p_kref);
-                               return readstr(off, va, n, buf);
+                               offset += snprintf(buf + offset, buflen - offset, "}\n");
+                               proc_decref(p);
+                               n = readstr(off, va, n, buf);
+                               kfree(buf);
+                               return n;
                        }
                case Qns:
                        //qlock(&p->debug);
                        if (waserror()) {
                                //qunlock(&p->debug);
-                               kref_put(&p->p_kref);
+                               proc_decref(p);
                                nexterror();
                        }
                        if (p->pgrp == NULL || p->pid != PID(c->qid))
@@ -1218,7 +1015,7 @@ regread:
                        if (mw->cddone) {
                                poperror();
                                //qunlock(&p->debug);
-                               kref_put(&p->p_kref);
+                               proc_decref(p);
                                return 0;
                        }
                        mntscan(mw, p);
@@ -1227,7 +1024,7 @@ regread:
                                i = snprintf(va, n, "cd %s\n", p->dot->name->s);
                                poperror();
                                //qunlock(&p->debug);
-                               kref_put(&p->p_kref);
+                               proc_decref(p);
                                return i;
                        }
                        int2flag(mw->cm->mflag, flag);
@@ -1243,21 +1040,14 @@ regread:
                                                         mw->cm->to->name->s, mw->mh->from->name->s);
                        poperror();
                        //qunlock(&p->debug);
-                       kref_put(&p->p_kref);
+                       proc_decref(p);
+                       return i;
+               case Qmaps:
+                       sza = c->aux;
+                       i = readmem(off, va, n, sza->buf, sza->size);
+                       proc_decref(p);
                        return i;
-#if 0
-               case Qnoteid:
-                       r = readnum(offset, va, n, p->noteid, NUMSIZE);
-                       kref_put(&p->p_kref);
-                       return r;
-               case Qfd:
-                       r = procfds(p, va, n, offset);
-                       kref_put(&p->p_kref);
-                       return r;
-#endif
        }
-
-
        error(EINVAL, "QID %d did not match any QIDs for #proc", QID(c->qid));
        return 0;       /* not reached */
 }
@@ -1313,7 +1103,7 @@ static long procwrite(struct chan *c, void *va, long n, int64_t off)
                error(ESRCH, ERROR_FIXME);
 
        if (waserror()) {
-               kref_put(&p->p_kref);
+               proc_decref(p);
                nexterror();
        }
        if (p->pid != PID(c->qid))
@@ -1329,7 +1119,7 @@ static long procwrite(struct chan *c, void *va, long n, int64_t off)
                        if (n >= sizeof buf - strlen(p->text) - 1)
                                error(E2BIG, ERROR_FIXME);
                        l = snprintf(buf, sizeof buf, "%s [%s]", p->text, (char *)va);
-                       args = kzmalloc(l + 1, KMALLOC_WAIT);
+                       args = kzmalloc(l + 1, MEM_WAIT);
                        if (args == NULL)
                                error(ENOMEM, ERROR_FIXME);
                        memmove(args, buf, l);
@@ -1378,7 +1168,7 @@ static long procwrite(struct chan *c, void *va, long n, int64_t off)
                        error(EFAIL, "unknown qid %#llux in procwrite\n", c->qid.path);
        }
        poperror();
-       kref_put(&p->p_kref);
+       proc_decref(p);
        return n;
 }
 
@@ -1519,8 +1309,15 @@ void procctlclosefiles(struct proc *p, int all, int fd)
 static void strace_shutdown(struct kref *a)
 {
        struct strace *strace = container_of(a, struct strace, procs);
-
-       qhangup(strace->q, "No more traces");
+       static const char base_msg[] = "Traced ~%lu syscs, Dropped %lu";
+       size_t msg_len = NUMSIZE64 * 2 + sizeof(base_msg);
+       char *msg = kmalloc(msg_len, 0);
+
+       if (msg)
+               snprintf(msg, msg_len, base_msg, strace->appx_nr_sysc,
+                        atomic_read(&strace->nr_drops));
+       qhangup(strace->q, msg);
+       kfree(msg);
 }
 
 static void strace_release(struct kref *a)
@@ -1555,7 +1352,7 @@ static void procctlreq(struct proc *p, char *va, int n)
        case CMstraceme:
                /* common allocation.  if we inherited, we might have one already */
                if (!p->strace) {
-                       strace = kmalloc(sizeof(*p->strace), KMALLOC_WAIT);
+                       strace = kzmalloc(sizeof(*p->strace), MEM_WAIT);
                        strace->q = qopen(65536, Qdropoverflow|Qcoalesce, NULL, NULL);
                        /* both of these refs are put when the proc is freed.  procs is for
                         * every process that has this p->strace.  users is procs + every
@@ -1585,9 +1382,6 @@ static void procctlreq(struct proc *p, char *va, int n)
        default:
                error(EFAIL, "Command not implemented");
                break;
-       case CMtrace:
-               systrace_trace_pid(p);
-               break;
        case CMclose:
                procctlclosefiles(p, 0, atoi(cb->f[1]));
                break;