makefs/msdos/msdosfs_fat.c

86 		usemap_alloc(struct msdosfsmount *pmp, u_long cn);
88 		usemap_free(struct msdosfsmount *pmp, u_long cn);
136 	u_long cn;
148 	cn = dep->de_StartCluster;
155 	if (cn == MSDOSFSROOT) {
189 	fc_lookup(dep, findcn, &i, &cn);
198 		if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD)
200 		byteoffset = FATOFS(pmp, cn);
213 		prevcn = cn;
220 			cn = getulong(bp->b_data + bo);
222 			cn = getushort(bp->b_data + bo);
224 			cn >>= 4;
225 		cn &= pmp->pm_fatmask;
233 		if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD)
234 			cn |= ~pmp->pm_fatmask;
237 	if (!MSDOSFSEOF(pmp, cn)) {
241 			*bnp = cntobn(pmp, cn);
243 			*cnp = cn;
244 		fc_setcache(dep, FC_LASTMAP, i, cn);
266 	u_long cn;
270 		cn = dep->de_fc[i].fc_frcn;
271 		if (cn != FCE_EMPTY && cn <= findcn) {
272 			if (closest == NULL || cn > closest->fc_frcn)
382 usemap_alloc(struct msdosfsmount *pmp, u_long cn)
385 	assert(cn <= pmp->pm_maxcluster);
387 	assert((pmp->pm_inusemap[cn / N_INUSEBITS] & (1 << (cn % N_INUSEBITS)))
391 	pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS);
397 usemap_free(struct msdosfsmount *pmp, u_long cn)
400 	assert(cn <= pmp->pm_maxcluster);
402 	assert((pmp->pm_inusemap[cn / N_INUSEBITS] & (1 << (cn % N_INUSEBITS)))
407 	pmp->pm_inusemap[cn / N_INUSEBITS] &= ~(1U << (cn % N_INUSEBITS));
433  * cn		- which cluster is of interest
447 fatentry(int function, struct msdosfsmount *pmp, u_long cn, u_long *oldcontents,
457 	    function, pmp, cn, oldcontents, newcontents);
486 	if (cn < CLUST_FIRST || cn > pmp->pm_maxcluster)
489 	byteoffset = FATOFS(pmp, cn);
502 		if (FAT12(pmp) & (cn & 1))
514 			if (cn & 1) {
738 	u_long len, newst, foundl, cn, l;
753 	for (cn = newst; cn <= pmp->pm_maxcluster;) {
754 		idx = cn / N_INUSEBITS;
756 		map |= (1U << (cn % N_INUSEBITS)) - 1;
758 			cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1;
759 			if ((l = chainlength(pmp, cn, count)) >= count)
760 				return (chainalloc(pmp, cn, count, fillwith, retcluster, got));
762 				foundcn = cn;
765 			cn += l + 1;
768 		cn += N_INUSEBITS - cn % N_INUSEBITS;
770 	for (cn = 0; cn < newst;) {
771 		idx = cn / N_INUSEBITS;
773 		map |= (1U << (cn % N_INUSEBITS)) - 1;
775 			cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1;
776 			if ((l = chainlength(pmp, cn, count)) >= count)
777 				return (chainalloc(pmp, cn, count, fillwith, retcluster, got));
779 				foundcn = cn;
782 			cn += l + 1;
785 		cn += N_INUSEBITS - cn % N_INUSEBITS;
870 	u_long bn, bo, bsize, byteoffset, cn, readcn;
879 	for (cn = 0; cn < (pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS; cn++)
880 		pmp->pm_inusemap[cn] = FULL_RUN;
888 	for (cn = 0; cn <= pmp->pm_maxcluster; cn++) {
889 		byteoffset = FATOFS(pmp, cn);
905 		if (FAT12(pmp) && (cn & 1))
913 		if (cn == 0 && readcn != ((pmp->pm_fatmask & 0xffffff00) |
922 			usemap_free(pmp, cn);
927 	for (cn = pmp->pm_maxcluster + 1; cn < (pmp->pm_maxcluster +
928 	    N_INUSEBITS) / N_INUSEBITS; cn++)
929 		pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS);
955 	u_long cn, got;
976 		error = pcbmap(dep, 0xffff, 0, &cn, 0);
997 			cn = 0;
999 			cn = dep->de_fc[FC_LASTFC].fc_fsrcn + 1;
1000 		error = clusteralloc(pmp, cn, count, CLUST_EOFE, &cn, &got);
1011 			*ncp = cn;
1016 			dep->de_StartCluster = cn;
1021 					 0, cn);
1023 				clusterfree(pmp, cn);
1033 		fc_setcache(dep, FC_LASTFC, frcn + got - 1, cn + got - 1);
1039 				    cntobn(pmp, cn++),