ref: 9ca327dd06c30341d984bff84727ea451b428db7
dir: /os/mpc/devboot.c/
#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 void bootreset(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 int bootstat(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, };