#include "lib9.h"#include "logfs.h"#include "local.h"#include "fcall.h" static char *copypages(LogfsServer *server, long newb, long oldb, ulong copymask, LogfsLowLevelReadResult *llrrp, int *markedbadp){	char *errmsg;	int page;	LogfsLowLevel *ll;	int ppb;	int pagesize;	uchar *buf; 	if(copymask == 0)		return nil; 	ll = server->ll;	ppb = 1 << ll->l2pagesperblock;	pagesize = 1 << ll->l2pagesize;	*markedbadp = 0;	*llrrp = LogfsLowLevelReadResultOk;	errmsg = nil; 	buf = logfsrealloc(nil, 1 << ll->l2pagesize);	if(buf == nil)		return Enomem; 	for(page = ppb - 1; page >= 0; page--) {		ulong m; 		m = logfsdatapagemask(1, page); 		if(copymask & m) {			LogfsLowLevelReadResult llrr;			if(server->trace > 1)				print("copypages read page %d\n", page);			errmsg = (*ll->readpagerange)(ll, buf, oldb, page, 0, pagesize, &llrr);			if(errmsg != nil)				break;			if(llrr > *llrrp)				*llrrp = llrr;			if(server->trace > 1)				print("copypages write page %d\n", page);			errmsg = (*ll->writepage)(ll, buf, newb, page);			if(errmsg) {				if(strcmp(errmsg, Eio) == 0) {					(*ll->markblockbad)(ll, newb);					*markedbadp = 1;				}				break;			}			if(server->trace > 1)				print("copypages end page %d\n", page);		}	}	logfsfreemem(buf);	return errmsg;} char *logfsservercopyactivedata(LogfsServer *server, long newb, long oldblockindex, int forcepage0, LogfsLowLevelReadResult *llrrp, int *markedbadp){	LogfsLowLevel *ll = server->ll;	ulong newpath;	DataBlock *ob;	char *errmsg; 	ob = server->datablock + oldblockindex;	if(forcepage0) {		u32int mask;		mask = logfsdatapagemask(1, 0);		if(ob->free & mask) {			ob->dirty |= mask;			ob->free |= mask;		}	}	if(server->trace > 1)		print("copyactivedata %ld: (%ld -> %ld)\n", oldblockindex, ob->block, newb);	newpath = mkdatapath(dataseqof(ob->path), copygensucc(copygenof(ob->path)));	(*ll->setblocktag)(ll, newb, LogfsTdata);	(*ll->setblockpath)(ll, newb, newpath);	errmsg = copypages(server, newb, ob->block, ~ob->free, llrrp, markedbadp);	if(errmsg)		return errmsg;	/*	 * anything dirty and free is now not dirty and free	 */	ob->dirty &= ~(ob->dirty & ob->free);	ob->block = newb;	ob->path = newpath;	return nil;} /* * unconditionally replace a datablock, and mark the old one bad * NB: if page 0 is apparently unused, force it to be copied, and mark * it free and dirty afterwards */char *logfsserverreplacedatablock(LogfsServer *server, long index){	long newb;	LogfsLowLevel *ll = server->ll; 	newb = logfsfindfreeblock(ll, AllocReasonReplace);	/* TODO - recover space by scavenging other blocks, or recycling the log */	while(newb >= 0) {		char *errmsg;		LogfsLowLevelReadResult llrr;		long oldblock;		int markedbad;		DataBlock *db; 		db = server->datablock + index;		oldblock = db->block;		errmsg = logfsservercopyactivedata(server, newb, index, 1, &llrr, &markedbad);		if(errmsg) {			if(!markedbad)				return errmsg;			newb = logfsfindfreeblock(ll, AllocReasonReplace);			continue;		}		(*ll->markblockbad)(ll, oldblock);		return nil;	}	return logfsefullreplacing;} char *logfsserverreplacelogblock(LogfsServer *server, LogSegment *seg, long index){	ulong opath;	LogfsLowLevel *ll = server->ll;	long oldb = seg->blockmap[index]; 	opath = (*ll->getblockpath)(ll, oldb); 	for(;;) {		long newb;		int pages;		char *errmsg;		LogfsLowLevelReadResult llrr;		int markedbad; 		newb  = logfsfindfreeblock(ll, AllocReasonReplace);		if(newb < 0)			return "full replacing log block";		/* TODO - scavenge data space for a spare block */		(*ll->setblocktag)(ll, newb, LogfsTlog);		(*ll->setblockpath)(ll, newb, mklogpath(seg->gen, index, copygensucc(copygenof(opath))));		if(index == seg->curblockindex)			pages = seg->curpage;		else			pages = 1 << server->ll->l2pagesperblock;		errmsg = copypages(server, newb, oldb, logfsdatapagemask(pages, 0), &llrr, &markedbad);		if(errmsg == nil) {			(*ll->markblockbad)(ll, seg->blockmap[index]);			seg->blockmap[index] = newb;			return nil;		}		if(!markedbad)			return errmsg;	}} char *logfsserverreplaceblock(LogfsServer *server, LogSegment *seg, long index){	if(seg)		return logfsserverreplacelogblock(server, seg, index);	else		return logfsserverreplacedatablock(server, index);}