#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"../port/error.h" enum{	Qdir,	Qboot,	Qmem,}; Dirtab bootdir[]={	".",			{Qdir,0,QTDIR},	0,	0555,	"boot",		{Qboot},	0,	0666,	"mem",		{Qmem},		0,	0666,}; #define	NBOOT	(sizeof bootdir/sizeof(Dirtab)) static voidbootreset(void){} static Chan*bootattach(char *spec){	return devattach('B', spec);} static Walkqid*bootwalk(Chan *c, Chan *nc, char **name, int nname){	return devwalk(c, nc, name, nname, bootdir, NBOOT, devgen);} static intbootstat(Chan *c, uchar *dp, int n){	return devstat(c, dp, n, bootdir, NBOOT, devgen);} static Chan*bootopen(Chan *c, int omode){	return devopen(c, omode, bootdir, NBOOT, devgen);} static void	 bootclose(Chan*){} static long	 bootread(Chan *c, void *buf, long n, vlong off){	ulong offset = off; 	switch((ulong)c->qid.path){ 	case Qdir:		return devdirread(c, buf, n, bootdir, NBOOT, devgen); 	case Qmem:		/* kernel memory */		if(offset>=KZERO && offset<KZERO+conf.npage*BY2PG){			if(offset+n > KZERO+conf.npage*BY2PG)				n = KZERO+conf.npage*BY2PG - offset;			memmove(buf, (char*)offset, n);			return n;		}		error(Ebadarg);	} 	error(Egreg);	return 0;	/* not reached */} static long	 bootwrite(Chan *c, void *buf, long n, vlong off){	ulong offset = off;	ulong pc;	uchar *p; 	switch((ulong)c->qid.path){	case Qmem:		/* kernel memory */		if(offset>=KZERO && offset<KZERO+conf.npage*BY2PG){			if(offset+n > KZERO+conf.npage*BY2PG)				n = KZERO+conf.npage*BY2PG - offset;			memmove((char*)offset, buf, n);			segflush((void*)offset, n);			return n;		}		error(Ebadarg); 	case Qboot:		p = (uchar*)buf;		pc = (((((p[0]<<8)|p[1])<<8)|p[2])<<8)|p[3];		if(pc < KZERO || pc >= KZERO+conf.npage*BY2PG)			error(Ebadarg);		splhi();		segflush((void*)pc, 64*1024);		gotopc(pc);	}	error(Ebadarg);	return 0;	/* not reached */} Dev bootdevtab = {	'B',	"boot", 	bootreset,	devinit,	devshutdown,	bootattach,	bootwalk,	bootstat,	bootopen,	devcreate,	bootclose,	bootread,	devbread,	bootwrite,	devbwrite,	devremove,	devwstat,};