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// SPDX-License-Identifier: GPL-2.0/* *  linux/fs/hpfs/alloc.c * *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 * *  HPFS bitmap operations */ #include "hpfs_fn.h" static void hpfs_claim_alloc(struct super_block *s, secno sec){	struct hpfs_sb_info *sbi = hpfs_sb(s);	if (sbi->sb_n_free != (unsigned)-1) {		if (unlikely(!sbi->sb_n_free)) {			hpfs_error(s, "free count underflow, allocating sector %08x", sec);			sbi->sb_n_free = -1;			return;		}		sbi->sb_n_free--;	}} static void hpfs_claim_free(struct super_block *s, secno sec){	struct hpfs_sb_info *sbi = hpfs_sb(s);	if (sbi->sb_n_free != (unsigned)-1) {		if (unlikely(sbi->sb_n_free >= sbi->sb_fs_size)) {			hpfs_error(s, "free count overflow, freeing sector %08x", sec);			sbi->sb_n_free = -1;			return;		}		sbi->sb_n_free++;	}} static void hpfs_claim_dirband_alloc(struct super_block *s, secno sec){	struct hpfs_sb_info *sbi = hpfs_sb(s);	if (sbi->sb_n_free_dnodes != (unsigned)-1) {		if (unlikely(!sbi->sb_n_free_dnodes)) {			hpfs_error(s, "dirband free count underflow, allocating sector %08x", sec);			sbi->sb_n_free_dnodes = -1;			return;		}		sbi->sb_n_free_dnodes--;	}} static void hpfs_claim_dirband_free(struct super_block *s, secno sec){	struct hpfs_sb_info *sbi = hpfs_sb(s);	if (sbi->sb_n_free_dnodes != (unsigned)-1) {		if (unlikely(sbi->sb_n_free_dnodes >= sbi->sb_dirband_size / 4)) {			hpfs_error(s, "dirband free count overflow, freeing sector %08x", sec);			sbi->sb_n_free_dnodes = -1;			return;		}		sbi->sb_n_free_dnodes++;	}} /* * Check if a sector is allocated in bitmap * This is really slow. Turned on only if chk==2 */ static int chk_if_allocated(struct super_block *s, secno sec, char *msg){	struct quad_buffer_head qbh;	__le32 *bmp;	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "chk"))) goto fail;	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f)) & 1) {		hpfs_error(s, "sector '%s' - %08x not allocated in bitmap", msg, sec);		goto fail1;	}	hpfs_brelse4(&qbh);	if (sec >= hpfs_sb(s)->sb_dirband_start && sec < hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {		unsigned ssec = (sec - hpfs_sb(s)->sb_dirband_start) / 4;		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto fail;		if ((le32_to_cpu(bmp[ssec >> 5]) >> (ssec & 0x1f)) & 1) {			hpfs_error(s, "sector '%s' - %08x not allocated in directory bitmap", msg, sec);			goto fail1;		}		hpfs_brelse4(&qbh);	}	return 0;	fail1:	hpfs_brelse4(&qbh);	fail:	return 1;} /* * Check if sector(s) have proper number and additionally check if they're * allocated in bitmap. */	int hpfs_chk_sectors(struct super_block *s, secno start, int len, char *msg){	if (start + len < start || start < 0x12 ||	    start + len > hpfs_sb(s)->sb_fs_size) {	    	hpfs_error(s, "sector(s) '%s' badly placed at %08x", msg, start);		return 1;	}	if (hpfs_sb(s)->sb_chk>=2) {		int i;		for (i = 0; i < len; i++)			if (chk_if_allocated(s, start + i, msg)) return 1;	}	return 0;} static secno alloc_in_bmp(struct super_block *s, secno near, unsigned n, unsigned forward){	struct quad_buffer_head qbh;	__le32 *bmp;	unsigned bs = near & ~0x3fff;	unsigned nr = (near & 0x3fff) & ~(n - 1);	/*unsigned mnr;*/	unsigned i, q;	int a, b;	secno ret = 0;	if (n != 1 && n != 4) {		hpfs_error(s, "Bad allocation size: %d", n);		return 0;	}	if (bs != ~0x3fff) {		if (!(bmp = hpfs_map_bitmap(s, near >> 14, &qbh, "aib"))) goto uls;	} else {		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto uls;	}	if (!tstbits(bmp, nr, n + forward)) {		ret = bs + nr;		goto rt;	}	q = nr + n; b = 0;	while ((a = tstbits(bmp, q, n + forward)) != 0) {		q += a;		if (n != 1) q = ((q-1)&~(n-1))+n;		if (!b) {			if (q>>5 != nr>>5) {				b = 1;				q = nr & 0x1f;			}		} else if (q > nr) break;	}	if (!a) {		ret = bs + q;		goto rt;	}	nr >>= 5;	/*for (i = nr + 1; i != nr; i++, i &= 0x1ff) */	i = nr;	do {		if (!le32_to_cpu(bmp[i])) goto cont;		if (n + forward >= 0x3f && le32_to_cpu(bmp[i]) != 0xffffffff) goto cont;		q = i<<5;		if (i > 0) {			unsigned k = le32_to_cpu(bmp[i-1]);			while (k & 0x80000000) {				q--; k <<= 1;			}		}		if (n != 1) q = ((q-1)&~(n-1))+n;		while ((a = tstbits(bmp, q, n + forward)) != 0) {			q += a;			if (n != 1) q = ((q-1)&~(n-1))+n;			if (q>>5 > i) break;		}		if (!a) {			ret = bs + q;			goto rt;		}		cont:		i++, i &= 0x1ff;	} while (i != nr);	rt:	if (ret) {		if (hpfs_sb(s)->sb_chk && ((ret >> 14) != (bs >> 14) || (le32_to_cpu(bmp[(ret & 0x3fff) >> 5]) | ~(((1 << n) - 1) << (ret & 0x1f))) != 0xffffffff)) {			hpfs_error(s, "Allocation doesn't work! Wanted %d, allocated at %08x", n, ret);			ret = 0;			goto b;		}		bmp[(ret & 0x3fff) >> 5] &= cpu_to_le32(~(((1 << n) - 1) << (ret & 0x1f)));		hpfs_mark_4buffers_dirty(&qbh);	}	b:	hpfs_brelse4(&qbh);	uls:	return ret;} /* * Allocation strategy:	1) search place near the sector specified *			2) search bitmap where free sectors last found *			3) search all bitmaps *			4) search all bitmaps ignoring number of pre-allocated *				sectors */ secno hpfs_alloc_sector(struct super_block *s, secno near, unsigned n, int forward){	secno sec;	int i;	unsigned n_bmps;	struct hpfs_sb_info *sbi = hpfs_sb(s);	int f_p = 0;	int near_bmp;	if (forward < 0) {		forward = -forward;		f_p = 1;	}	n_bmps = (sbi->sb_fs_size + 0x4000 - 1) >> 14;	if (near && near < sbi->sb_fs_size) {		if ((sec = alloc_in_bmp(s, near, n, f_p ? forward : forward/4))) goto ret;		near_bmp = near >> 14;	} else near_bmp = n_bmps / 2;	/*	if (b != -1) {		if ((sec = alloc_in_bmp(s, b<<14, n, f_p ? forward : forward/2))) {			b &= 0x0fffffff;			goto ret;		}		if (b > 0x10000000) if ((sec = alloc_in_bmp(s, (b&0xfffffff)<<14, n, f_p ? forward : 0))) goto ret;	*/	if (!f_p) if (forward > sbi->sb_max_fwd_alloc) forward = sbi->sb_max_fwd_alloc;	less_fwd:	for (i = 0; i < n_bmps; i++) {		if (near_bmp+i < n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i) << 14, n, forward)))) {			sbi->sb_c_bitmap = near_bmp+i;			goto ret;		}			if (!forward) {			if (near_bmp-i-1 >= 0 && ((sec = alloc_in_bmp(s, (near_bmp-i-1) << 14, n, forward)))) {				sbi->sb_c_bitmap = near_bmp-i-1;				goto ret;			}		} else {			if (near_bmp+i >= n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i-n_bmps) << 14, n, forward)))) {				sbi->sb_c_bitmap = near_bmp+i-n_bmps;				goto ret;			}		}		if (i == 1 && sbi->sb_c_bitmap != -1 && ((sec = alloc_in_bmp(s, (sbi->sb_c_bitmap) << 14, n, forward)))) {			goto ret;		}	}	if (!f_p) {		if (forward) {			sbi->sb_max_fwd_alloc = forward * 3 / 4;			forward /= 2;			goto less_fwd;		}	}	sec = 0;	ret:	if (sec) {		i = 0;		do			hpfs_claim_alloc(s, sec + i);		while (unlikely(++i < n));	}	if (sec && f_p) {		for (i = 0; i < forward; i++) {			if (!hpfs_alloc_if_possible(s, sec + n + i)) {				hpfs_error(s, "Prealloc doesn't work! Wanted %d, allocated at %08x, can't allocate %d", forward, sec, i);				sec = 0;				break;			}		}	}	return sec;} static secno alloc_in_dirband(struct super_block *s, secno near){	unsigned nr = near;	secno sec;	struct hpfs_sb_info *sbi = hpfs_sb(s);	if (nr < sbi->sb_dirband_start)		nr = sbi->sb_dirband_start;	if (nr >= sbi->sb_dirband_start + sbi->sb_dirband_size)		nr = sbi->sb_dirband_start + sbi->sb_dirband_size - 4;	nr -= sbi->sb_dirband_start;	nr >>= 2;	sec = alloc_in_bmp(s, (~0x3fff) | nr, 1, 0);	if (!sec) return 0;	hpfs_claim_dirband_alloc(s, sec);	return ((sec & 0x3fff) << 2) + sbi->sb_dirband_start;} /* Alloc sector if it's free */ int hpfs_alloc_if_possible(struct super_block *s, secno sec){	struct quad_buffer_head qbh;	__le32 *bmp;	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "aip"))) goto end;	if (le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) & (1 << (sec & 0x1f))) {		bmp[(sec & 0x3fff) >> 5] &= cpu_to_le32(~(1 << (sec & 0x1f)));		hpfs_mark_4buffers_dirty(&qbh);		hpfs_brelse4(&qbh);		hpfs_claim_alloc(s, sec);		return 1;	}	hpfs_brelse4(&qbh);	end:	return 0;} /* Free sectors in bitmaps */ void hpfs_free_sectors(struct super_block *s, secno sec, unsigned n){	struct quad_buffer_head qbh;	__le32 *bmp;	struct hpfs_sb_info *sbi = hpfs_sb(s);	/*pr_info("2 - ");*/	if (!n) return;	if (sec < 0x12) {		hpfs_error(s, "Trying to free reserved sector %08x", sec);		return;	}	sbi->sb_max_fwd_alloc += n > 0xffff ? 0xffff : n;	if (sbi->sb_max_fwd_alloc > 0xffffff) sbi->sb_max_fwd_alloc = 0xffffff;	new_map:	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "free"))) {		return;	}		new_tst:	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f) & 1)) {		hpfs_error(s, "sector %08x not allocated", sec);		hpfs_brelse4(&qbh);		return;	}	bmp[(sec & 0x3fff) >> 5] |= cpu_to_le32(1 << (sec & 0x1f));	hpfs_claim_free(s, sec);	if (!--n) {		hpfs_mark_4buffers_dirty(&qbh);		hpfs_brelse4(&qbh);		return;	}		if (!(++sec & 0x3fff)) {		hpfs_mark_4buffers_dirty(&qbh);		hpfs_brelse4(&qbh);		goto new_map;	}	goto new_tst;} /* * Check if there are at least n free dnodes on the filesystem. * Called before adding to dnode. If we run out of space while * splitting dnodes, it would corrupt dnode tree. */ int hpfs_check_free_dnodes(struct super_block *s, int n){	int n_bmps = (hpfs_sb(s)->sb_fs_size + 0x4000 - 1) >> 14;	int b = hpfs_sb(s)->sb_c_bitmap & 0x0fffffff;	int i, j;	__le32 *bmp;	struct quad_buffer_head qbh;	if ((bmp = hpfs_map_dnode_bitmap(s, &qbh))) {		for (j = 0; j < 512; j++) {			unsigned k;			if (!le32_to_cpu(bmp[j])) continue;			for (k = le32_to_cpu(bmp[j]); k; k >>= 1) if (k & 1) if (!--n) {				hpfs_brelse4(&qbh);				return 0;			}		}		hpfs_brelse4(&qbh);	}	i = 0;	if (hpfs_sb(s)->sb_c_bitmap != -1) {		bmp = hpfs_map_bitmap(s, b, &qbh, "chkdn1");		goto chk_bmp;	}	chk_next:	if (i == b) i++;	if (i >= n_bmps) return 1;	bmp = hpfs_map_bitmap(s, i, &qbh, "chkdn2");	chk_bmp:	if (bmp) {		for (j = 0; j < 512; j++) {			u32 k;			if (!le32_to_cpu(bmp[j])) continue;			for (k = 0xf; k; k <<= 4)				if ((le32_to_cpu(bmp[j]) & k) == k) {					if (!--n) {						hpfs_brelse4(&qbh);						return 0;					}				}		}		hpfs_brelse4(&qbh);	}	i++;	goto chk_next;} void hpfs_free_dnode(struct super_block *s, dnode_secno dno){	if (hpfs_sb(s)->sb_chk) if (dno & 3) {		hpfs_error(s, "hpfs_free_dnode: dnode %08x not aligned", dno);		return;	}	if (dno < hpfs_sb(s)->sb_dirband_start ||	    dno >= hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {		hpfs_free_sectors(s, dno, 4);	} else {		struct quad_buffer_head qbh;		__le32 *bmp;		unsigned ssec = (dno - hpfs_sb(s)->sb_dirband_start) / 4;		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {			return;		}		bmp[ssec >> 5] |= cpu_to_le32(1 << (ssec & 0x1f));		hpfs_mark_4buffers_dirty(&qbh);		hpfs_brelse4(&qbh);		hpfs_claim_dirband_free(s, dno);	}} struct dnode *hpfs_alloc_dnode(struct super_block *s, secno near,			 dnode_secno *dno, struct quad_buffer_head *qbh){	struct dnode *d;	if (hpfs_get_free_dnodes(s) > FREE_DNODES_ADD) {		if (!(*dno = alloc_in_dirband(s, near)))			if (!(*dno = hpfs_alloc_sector(s, near, 4, 0))) return NULL;	} else {		if (!(*dno = hpfs_alloc_sector(s, near, 4, 0)))			if (!(*dno = alloc_in_dirband(s, near))) return NULL;	}	if (!(d = hpfs_get_4sectors(s, *dno, qbh))) {		hpfs_free_dnode(s, *dno);		return NULL;	}	memset(d, 0, 2048);	d->magic = cpu_to_le32(DNODE_MAGIC);	d->first_free = cpu_to_le32(52);	d->dirent[0] = 32;	d->dirent[2] = 8;	d->dirent[30] = 1;	d->dirent[31] = 255;	d->self = cpu_to_le32(*dno);	return d;} struct fnode *hpfs_alloc_fnode(struct super_block *s, secno near, fnode_secno *fno,			  struct buffer_head **bh){	struct fnode *f;	if (!(*fno = hpfs_alloc_sector(s, near, 1, FNODE_ALLOC_FWD))) return NULL;	if (!(f = hpfs_get_sector(s, *fno, bh))) {		hpfs_free_sectors(s, *fno, 1);		return NULL;	}		memset(f, 0, 512);	f->magic = cpu_to_le32(FNODE_MAGIC);	f->ea_offs = cpu_to_le16(0xc4);	f->btree.n_free_nodes = 8;	f->btree.first_free = cpu_to_le16(8);	return f;} struct anode *hpfs_alloc_anode(struct super_block *s, secno near, anode_secno *ano,			  struct buffer_head **bh){	struct anode *a;	if (!(*ano = hpfs_alloc_sector(s, near, 1, ANODE_ALLOC_FWD))) return NULL;	if (!(a = hpfs_get_sector(s, *ano, bh))) {		hpfs_free_sectors(s, *ano, 1);		return NULL;	}	memset(a, 0, 512);	a->magic = cpu_to_le32(ANODE_MAGIC);	a->self = cpu_to_le32(*ano);	a->btree.n_free_nodes = 40;	a->btree.n_used_nodes = 0;	a->btree.first_free = cpu_to_le16(8);	return a;} static unsigned find_run(__le32 *bmp, unsigned *idx){	unsigned len;	while (tstbits(bmp, *idx, 1)) {		(*idx)++;		if (unlikely(*idx >= 0x4000))			return 0;	}	len = 1;	while (!tstbits(bmp, *idx + len, 1))		len++;	return len;

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