/* cached-worm file server */

/* cached-worm file server */
#include "all.h"
#include "io.h"

Map *devmap;

Biobuf bin;
int chatty = 0;
int sfd = -1;

void
machinit(void)
{
active.exiting = 0;
}

void
panic(char *fmt, ...)
{
int n;
va_list arg;
char buf[PRINTSIZE];

va_start(arg, fmt);
n = vseprint(buf, buf + sizeof buf, fmt, arg) - buf;
va_end(arg);
buf[n] = '\0';
fprint(2, "panic: %s\n", buf);
exit();
}

int
okay(char *quest)
{
char *ln;

print("okay to %s? ", quest);
if ((ln = Brdline(&bin, '\n')) == nil)
return 0;
ln[Blinelen(&bin)-1] = '\0';
if (isascii(*ln) && isupper(*ln))
*ln = tolower(*ln);
return *ln == 'y';
}

static void
mapinit(char *mapfile)
{
int nf;
char *ln;
char *fields[2];
Biobuf *bp;
Map *map;

if (mapfile == nil)
return;
bp = Bopen(mapfile, OREAD);
if (bp == nil)
sysfatal("can't read %s", mapfile);
devmap = nil;
while((ln = Brdline(bp, '\n')) != nil) {
ln[Blinelen(bp)-1] = '\0';
if(*ln == '\0' || *ln == '#')
continue;
nf = tokenize(ln, fields, nelem(fields));
if(nf != 2)
continue;
if(testconfig(fields[0]) != 0) {
print("bad `from' device %s in %s\n",
fields[0], mapfile);
continue;
}
map = ialloc(sizeof(Map), 0);
map->from = strdup(fields[0]);
map->to = strdup(fields[1]);
map->fdev = iconfig(fields[0]);
map->tdev = nil;
if(access(map->to, AEXIST) < 0) {
/*
* map->to isn't an existing file, so it had better be
* a config string for a device.
*/
if(testconfig(fields[1]) == 0)
map->tdev = iconfig(fields[1]);
}
/* else map->to is the replacement file name */
map->next = devmap;
devmap = map;
}
Bterm(bp);
}

static void
confinit(void)
{
conf.nmach = 1;

conf.nuid = 1000;
conf.nserve = 15; /* tunable */
conf.nfile = 30000;
conf.nlgmsg = 100;
conf.nsmmsg = 500;

localconfinit();

conf.nwpath = conf.nfile*8;
conf.gidspace = conf.nuid*3;

cons.flags = 0;

if (conf.devmap)
mapinit(conf.devmap);
}

static int
srvfd(char *s, int mode, int sfd)
{
int fd;
char buf[32];

fd = create(s, ORCLOSE|OWRITE, mode);
if(fd < 0){
remove(s);
fd = create(s, ORCLOSE|OWRITE, mode);
if(fd < 0)
panic(s);
}
sprint(buf, "%d", sfd);
if(write(fd, buf, strlen(buf)) != strlen(buf))
panic("srv write");
return sfd;
}

static void
postservice(char *name)
{
char buf[3*NAMELEN];
int p[2];

if(name == nil || *name == 0)
panic("no service name");

/* serve 9p for -s */
if(sfd >= 0){
srvchan(sfd, "stdio");
sfd = -1;
}

/* post 9p service */
if(pipe(p) < 0)
panic("can't make a pipe");
snprint(buf, sizeof(buf), "#s/%s", name);
srvfd(buf, 0666, p[0]);
close(p[0]);
srvchan(p[1], buf);

/* post cmd service */
if(pipe(p) < 0)
panic("can't make a pipe");
snprint(buf, sizeof(buf), "#s/%s.cmd", name);
srvfd(buf, 0660, p[0]);
close(p[0]);

/* use it as stdin */
dup(p[1], 0);
close(p[1]);
}

/*
* compute BUFSIZE*(NDBLOCK+INDPERBUF+INDPERBUF²+INDPERBUF³+INDPERBUF⁴)
* while watching for overflow; in that case, return 0.
*/

static uvlong
adduvlongov(uvlong a, uvlong b)
{
uvlong r = a + b;

if (r < a || r < b)
return 0;
return r;
}

static uvlong
muluvlongov(uvlong a, uvlong b)
{
uvlong r = a * b;

if (a != 0 && r/a != b || r < a || r < b)
return 0;
return r;
}

static uvlong
maxsize(void)
{
int i;
uvlong max = NDBLOCK, ind = 1;

for (i = 0; i < NIBLOCK; i++) {
ind = muluvlongov(ind, INDPERBUF); /* power of INDPERBUF */
if (ind == 0)
return 0;
max = adduvlongov(max, ind);
if (max == 0)
return 0;
}
return muluvlongov(max, BUFSIZE);
}

enum {
INDPERBUF² = ((uvlong)INDPERBUF*INDPERBUF),
INDPERBUF⁴ = ((uvlong)INDPERBUF²*INDPERBUF²),
};

static void
printsizes(void)
{
uvlong max = maxsize();

print("\tblock size = %d; ", RBUFSIZE);
if (max == 0)
print("max file size exceeds 2⁶⁴ bytes\n");
else {
uvlong offlim = 1ULL << (sizeof(Off)*8 - 1);

if (max >= offlim)
max = offlim - 1;
print("max file size = %,llud\n", (Wideoff)max);
}
if (INDPERBUF²/INDPERBUF != INDPERBUF)
print("overflow computing INDPERBUF²\n");
if (INDPERBUF⁴/INDPERBUF² != INDPERBUF²)
print("overflow computing INDPERBUF⁴\n");
print("\tINDPERBUF = %d, INDPERBUF^4 = %,lld, ", INDPERBUF,
(Wideoff)INDPERBUF⁴);
print("CEPERBK = %d\n", CEPERBK);
print("\tsizeofs: Dentry = %d, Cache = %d\n",
sizeof(Dentry), sizeof(Cache));
}

void
usage(void)
{
fprint(2, "usage: %s [ -csC ] [-n service] [ -a ann-str ] [ -m dev-map ] [-f config-dev ]\n", argv0);
exits("usage");
}

void
main(int argc, char **argv)
{
int i, nets = 0;
char *ann, *sname = nil;

rfork(RFNOTEG);
formatinit();
machinit();
conf.confdev = "/dev/sdC0/fscache";
conf.newcache = 0;

ARGBEGIN{
case 'a': /* announce on this net */
ann = EARGF(usage());
if (nets >= Maxnets) {
fprint(2, "%s: too many networks to announce: %s\n",
argv0, ann);
exits("too many nets");
}
annstrs[nets++] = ann;
break;
case 'n':
sname = EARGF(usage());
break;
case 's':
dup(0, -1);
sfd = dup(1, -1);
close(0);
if(open("/dev/cons", OREAD) < 0)
open("#c/cons", OREAD);
close(1);
if(open("/dev/cons", OWRITE) < 0)
open("#c/cons", OWRITE);
break;
case 'C': /* use new, faster cache layout */
conf.newcache = 1;
break;
case 'c':
conf.configfirst++;
break;
case 'f': /* device / partition / file */
conf.confdev = EARGF(usage());
break;
case 'm': /* name device-map file */
conf.devmap = EARGF(usage());
break;
case 'd':
chatty++;
break;
default:
usage();
break;
}ARGEND

if(argc != 0)
usage();

Binit(&bin, 0, OREAD);
confinit();

if(chatty){
print("\nPlan 9 %d-bit cached-worm file server with %d-deep indir blks\n",
sizeof(Off)*8 - 1, NIBLOCK);
printsizes();
}

qlock(&reflock);
qunlock(&reflock);
serveq = newqueue(1000, "9P service"); /* tunable */
raheadq = newqueue(1000, "readahead"); /* tunable */

mbinit();
netinit();
scsiinit();

files = ialloc((uintptr)conf.nfile * sizeof(*files), 0);
for(i=0; i < conf.nfile; i++) {
qlock(&files[i]);
qunlock(&files[i]);
}

wpaths = ialloc((uintptr)conf.nwpath * sizeof(*wpaths), 0);
uid = ialloc((uintptr)conf.nuid * sizeof(*uid), 0);
gidspace = ialloc((uintptr)conf.gidspace * sizeof(*gidspace), 0);

iobufinit();

arginit();
boottime = time(nil);

sysinit();
srvinit();

/*
* post filedescriptors to /srv
*/
postservice(sname != nil ? sname : service);

/*
* processes to read the console
*/
consserve();

/*
* Ethernet i/o processes
*/
netstart();

/*
* read ahead processes
*/
newproc(rahead, 0, "rah");

/*
* server processes
*/
for(i=0; i < conf.nserve; i++)
newproc(serve, 0, "srv");

/*
* worm "dump" copy process
*/
newproc(wormcopy, 0, "wcp");

/*
* "sync" copy process
*/
newproc(synccopy, 0, "scp");

/* success */
exits(nil);
}

/*
* read ahead processes.
* read message from q and then
* read the device.
*/
int
rbcmp(void *va, void *vb)
{
Rabuf *ra, *rb;

ra = *(Rabuf**)va;
rb = *(Rabuf**)vb;
if(rb == 0)
return 1;
if(ra == 0)
return -1;
if(ra->dev > rb->dev)
return 1;
if(ra->dev < rb->dev)
return -1;
if(ra->addr > rb->addr)
return 1;
if(ra->addr < rb->addr)
return -1;
return 0;
}

void
rahead(void *)
{
Rabuf *rb[50];
Iobuf *p;
int i, n;

for (;;) {
rb[0] = fs_recv(raheadq, 0);
for(n = 1; n < nelem(rb); n++) {
if(raheadq->count <= 0)
break;
rb[n] = fs_recv(raheadq, 0);
}
qsort(rb, n, sizeof rb[0], rbcmp);
for(i = 0; i < n; i++) {
if(rb[i] == 0)
continue;
p = getbuf(rb[i]->dev, rb[i]->addr, Brd);
if(p)
putbuf(p);
lock(&rabuflock);
rb[i]->link = rabuffree;
rabuffree = rb[i];
unlock(&rabuflock);
}
}
}

/*
* main filesystem server loop.
* entered by many processes.
* they wait for message buffers and
* then process them.
*/
void
serve(void *)
{
int i;
Chan *cp;
Msgbuf *mb;

for (;;) {
qlock(&reflock);
/* read 9P request from a network input process */
mb = fs_recv(serveq, 0);
/* fs kernel sets chan in /sys/src/fs/ip/il.c:/^getchan */
cp = mb->chan;
if (cp == nil)
panic("serve: nil mb->chan");
rlock(&cp->reflock);
qunlock(&reflock);

rlock(&mainlock);

if (mb->data == nil)
panic("serve: nil mb->data");
if(cp->protocol != nil){
/* process the request, generate an answer and reply */
cp->protocol(mb);
} else {
/* do we recognise the protocol in this packet? */
for(i = 0; fsprotocol[i] != nil; i++)
if(fsprotocol[i](mb) != 0) {
cp->protocol = fsprotocol[i];
break;
}
if(cp->protocol == nil && (chatty > 1)){
fprint(2, "no protocol for message\n");
hexdump(mb->data, 12);
}
}

mbfree(mb);
runlock(&mainlock);
runlock(&cp->reflock);
}
}

void
exit(void)
{
lock(&active);
active.exiting = 1;
unlock(&active);

fprint(2, "halted at %T.\n", time(nil));
postnote(PNGROUP, getpid(), "die");
exits(nil);
}

enum {
DUMPTIME = 5, /* 5 am */
WEEKMASK = 0, /* every day (1=sun, 2=mon, 4=tue, etc.) */
};

/*
* calculate the next dump time.
* minimum delay is 100 minutes.
*/
Timet
nextdump(Timet t)
{
Timet nddate = nextime(t+MINUTE(100), DUMPTIME, WEEKMASK);

if(!conf.nodump && chatty)
fprint(2, "next dump at %T\n", nddate);
return nddate;
}

/*
* process to copy dump blocks from
* cache to worm. it runs flat out when
* it gets work, but only looks for
* work every 10 seconds.
*/
void
wormcopy(void *)
{
int f, dorecalc = 1;
Timet dt, t = 0, nddate = 0, ntoytime = 0;
Filsys *fs;

for (;;) {
if (dorecalc) {
dorecalc = 0;
t = time(nil);
nddate = nextdump(t); /* chatters */
ntoytime = time(nil);
}
dt = time(nil) - t;
if(dt < 0 || dt > MINUTE(100)) {
dorecalc = 1;
continue;
}
t += dt;
f = 0;
if(t > ntoytime)
ntoytime = time(nil) + HOUR(1);
else if(t > nddate) {
if(!conf.nodump) {
fprint(2, "automatic dump %T\n", t);
for(fs=filsys; fs->name; fs++)
if(fs->dev->type == Devcw)
cfsdump(fs);
}
dorecalc = 1;
} else {
rlock(&mainlock);
for(fs=filsys; fs->name; fs++)
if(fs->dev->type == Devcw)
f |= dumpblock(fs->dev);
runlock(&mainlock);
if(!f)
delay(10000);
wormprobe();
}
}
}

/*
* process to synch blocks
* it puts out a block/cache-line every second
* it waits 10 seconds if caught up.
* in both cases, it takes about 10 seconds
* to get up-to-date.
*/
void
synccopy(void *)
{
int f;

for (;;) {
rlock(&mainlock);
f = syncblock();
runlock(&mainlock);
if(!f)
delay(10000);
else
delay(1000);
}
}

Devsize
inqsize(char *file)
{
int nf;
char *ln, *end, *data;
char *fields[4];
Devsize rv = -1;
Biobuf *bp;

data = malloc(strlen(file) + 5 + 1);
strcpy(data, file);
end = strstr(data, "/data");
if (end == nil)
strcat(data, "/ctl");
else
strcpy(end, "/ctl");
bp = Bopen(data, OREAD);
if (bp) {
while (rv < 0 && (ln = Brdline(bp, '\n')) != nil) {
ln[Blinelen(bp)-1] = '\0';
nf = tokenize(ln, fields, nelem(fields));
if (nf == 3 && strcmp(fields[0], "geometry") == 0)
rv = atoi(fields[2]);
}
Bterm(bp);
}
free(data);
return rv;
}