[mirror_ubuntu-bionic-kernel.git] / fs / hpfs / alloc.c

// 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;
}

static int do_trim(struct super_block *s, secno start, unsigned len, secno limit_start, secno limit_end, unsigned minlen, unsigned *result)
{
	int err;
	secno end;
	if (fatal_signal_pending(current))
		return -EINTR;
	end = start + len;
	if (start < limit_start)
		start = limit_start;
	if (end > limit_end)
		end = limit_end;
	if (start >= end)
		return 0;
	if (end - start < minlen)
		return 0;
	err = sb_issue_discard(s, start, end - start, GFP_NOFS, 0);
	if (err)
		return err;
	*result += end - start;
	return 0;
}

int hpfs_trim_fs(struct super_block *s, u64 start, u64 end, u64 minlen, unsigned *result)
{
	int err = 0;
	struct hpfs_sb_info *sbi = hpfs_sb(s);
	unsigned idx, len, start_bmp, end_bmp;
	__le32 *bmp;
	struct quad_buffer_head qbh;

	*result = 0;
	if (!end || end > sbi->sb_fs_size)
		end = sbi->sb_fs_size;
	if (start >= sbi->sb_fs_size)
		return 0;
	if (minlen > 0x4000)
		return 0;
	if (start < sbi->sb_dirband_start + sbi->sb_dirband_size && end > sbi->sb_dirband_start) {
		hpfs_lock(s);
		if (sb_rdonly(s)) {
			err = -EROFS;
			goto unlock_1;
		}
		if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
			err = -EIO;
			goto unlock_1;
		}
		idx = 0;
		while ((len = find_run(bmp, &idx)) && !err) {
			err = do_trim(s, sbi->sb_dirband_start + idx * 4, len * 4, start, end, minlen, result);
			idx += len;
		}
		hpfs_brelse4(&qbh);
unlock_1:
		hpfs_unlock(s);
	}
	start_bmp = start >> 14;
	end_bmp = (end + 0x3fff) >> 14;
	while (start_bmp < end_bmp && !err) {
		hpfs_lock(s);
		if (sb_rdonly(s)) {
			err = -EROFS;
			goto unlock_2;
		}
		if (!(bmp = hpfs_map_bitmap(s, start_bmp, &qbh, "trim"))) {
			err = -EIO;
			goto unlock_2;
		}
		idx = 0;
		while ((len = find_run(bmp, &idx)) && !err) {
			err = do_trim(s, (start_bmp << 14) + idx, len, start, end, minlen, result);
			idx += len;
		}
		hpfs_brelse4(&qbh);
unlock_2:
		hpfs_unlock(s);
		start_bmp++;
	}
	return err;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/hpfs/alloc.c
	4	*
	5	* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
	6	*
	7	* HPFS bitmap operations
	8	*/
	9
	10	#include "hpfs_fn.h"
	11
2cbe5c76 MP	12	static void hpfs_claim_alloc(struct super_block *s, secno sec)
	13	{
	14	struct hpfs_sb_info *sbi = hpfs_sb(s);
	15	if (sbi->sb_n_free != (unsigned)-1) {
	16	if (unlikely(!sbi->sb_n_free)) {
	17	hpfs_error(s, "free count underflow, allocating sector %08x", sec);
	18	sbi->sb_n_free = -1;
	19	return;
	20	}
	21	sbi->sb_n_free--;
	22	}
	23	}
	24
	25	static void hpfs_claim_free(struct super_block *s, secno sec)
	26	{
	27	struct hpfs_sb_info *sbi = hpfs_sb(s);
	28	if (sbi->sb_n_free != (unsigned)-1) {
	29	if (unlikely(sbi->sb_n_free >= sbi->sb_fs_size)) {
	30	hpfs_error(s, "free count overflow, freeing sector %08x", sec);
	31	sbi->sb_n_free = -1;
	32	return;
	33	}
	34	sbi->sb_n_free++;
	35	}
	36	}
	37
	38	static void hpfs_claim_dirband_alloc(struct super_block *s, secno sec)
	39	{
	40	struct hpfs_sb_info *sbi = hpfs_sb(s);
	41	if (sbi->sb_n_free_dnodes != (unsigned)-1) {
	42	if (unlikely(!sbi->sb_n_free_dnodes)) {
	43	hpfs_error(s, "dirband free count underflow, allocating sector %08x", sec);
	44	sbi->sb_n_free_dnodes = -1;
	45	return;
	46	}
	47	sbi->sb_n_free_dnodes--;
	48	}
	49	}
	50
	51	static void hpfs_claim_dirband_free(struct super_block *s, secno sec)
	52	{
	53	struct hpfs_sb_info *sbi = hpfs_sb(s);
	54	if (sbi->sb_n_free_dnodes != (unsigned)-1) {
	55	if (unlikely(sbi->sb_n_free_dnodes >= sbi->sb_dirband_size / 4)) {
	56	hpfs_error(s, "dirband free count overflow, freeing sector %08x", sec);
	57	sbi->sb_n_free_dnodes = -1;
	58	return;
	59	}
	60	sbi->sb_n_free_dnodes++;
	61	}
	62	}
	63
1da177e4 LT	64	/*
	65	* Check if a sector is allocated in bitmap
	66	* This is really slow. Turned on only if chk==2
	67	*/
	68
	69	static int chk_if_allocated(struct super_block s, secno sec, char msg)
	70	{
	71	struct quad_buffer_head qbh;
52576da3	72	__le32 *bmp;
1da177e4	73	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "chk"))) goto fail;
52576da3	74	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f)) & 1) {
1da177e4 LT	75	hpfs_error(s, "sector '%s' - %08x not allocated in bitmap", msg, sec);
	76	goto fail1;
	77	}
	78	hpfs_brelse4(&qbh);
	79	if (sec >= hpfs_sb(s)->sb_dirband_start && sec < hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
	80	unsigned ssec = (sec - hpfs_sb(s)->sb_dirband_start) / 4;
	81	if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto fail;
0b69760b	82	if ((le32_to_cpu(bmp[ssec >> 5]) >> (ssec & 0x1f)) & 1) {
1da177e4 LT	83	hpfs_error(s, "sector '%s' - %08x not allocated in directory bitmap", msg, sec);
	84	goto fail1;
	85	}
	86	hpfs_brelse4(&qbh);
	87	}
	88	return 0;
	89	fail1:
	90	hpfs_brelse4(&qbh);
	91	fail:
	92	return 1;
	93	}
	94
	95	/*
	96	* Check if sector(s) have proper number and additionally check if they're
	97	* allocated in bitmap.
	98	*/
	99
	100	int hpfs_chk_sectors(struct super_block s, secno start, int len, char msg)
	101	{
	102	if (start + len < start \|\| start < 0x12 \|\|
	103	start + len > hpfs_sb(s)->sb_fs_size) {
	104	hpfs_error(s, "sector(s) '%s' badly placed at %08x", msg, start);
	105	return 1;
	106	}
	107	if (hpfs_sb(s)->sb_chk>=2) {
	108	int i;
	109	for (i = 0; i < len; i++)
	110	if (chk_if_allocated(s, start + i, msg)) return 1;
	111	}
	112	return 0;
	113	}
	114
	115	static secno alloc_in_bmp(struct super_block *s, secno near, unsigned n, unsigned forward)
	116	{
	117	struct quad_buffer_head qbh;
52576da3	118	__le32 *bmp;
1da177e4 LT	119	unsigned bs = near & ~0x3fff;
	120	unsigned nr = (near & 0x3fff) & ~(n - 1);
	121	/unsigned mnr;/
	122	unsigned i, q;
	123	int a, b;
	124	secno ret = 0;
	125	if (n != 1 && n != 4) {
	126	hpfs_error(s, "Bad allocation size: %d", n);
	127	return 0;
	128	}
1da177e4 LT	129	if (bs != ~0x3fff) {
	130	if (!(bmp = hpfs_map_bitmap(s, near >> 14, &qbh, "aib"))) goto uls;
	131	} else {
	132	if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) goto uls;
	133	}
	134	if (!tstbits(bmp, nr, n + forward)) {
	135	ret = bs + nr;
	136	goto rt;
	137	}
1da177e4 LT	138	q = nr + n; b = 0;
	139	while ((a = tstbits(bmp, q, n + forward)) != 0) {
	140	q += a;
	141	if (n != 1) q = ((q-1)&~(n-1))+n;
	142	if (!b) {
	143	if (q>>5 != nr>>5) {
	144	b = 1;
	145	q = nr & 0x1f;
	146	}
	147	} else if (q > nr) break;
	148	}
	149	if (!a) {
	150	ret = bs + q;
	151	goto rt;
	152	}
	153	nr >>= 5;
0b69760b	154	/for (i = nr + 1; i != nr; i++, i &= 0x1ff) /
1da177e4 LT	155	i = nr;
1da177e4 LT	156	do {
0b69760b MP	157	if (!le32_to_cpu(bmp[i])) goto cont;
0b69760b MP	158	if (n + forward >= 0x3f && le32_to_cpu(bmp[i]) != 0xffffffff) goto cont;
1da177e4 LT	159	q = i<<5;
1da177e4 LT	160	if (i > 0) {
0b69760b	161	unsigned k = le32_to_cpu(bmp[i-1]);
1da177e4 LT	162	while (k & 0x80000000) {
	163	q--; k <<= 1;
	164	}
	165	}
	166	if (n != 1) q = ((q-1)&~(n-1))+n;
	167	while ((a = tstbits(bmp, q, n + forward)) != 0) {
	168	q += a;
	169	if (n != 1) q = ((q-1)&~(n-1))+n;
	170	if (q>>5 > i) break;
	171	}
	172	if (!a) {
	173	ret = bs + q;
	174	goto rt;
	175	}
	176	cont:
	177	i++, i &= 0x1ff;
	178	} while (i != nr);
	179	rt:
	180	if (ret) {
0b69760b	181	if (hpfs_sb(s)->sb_chk && ((ret >> 14) != (bs >> 14) \|\| (le32_to_cpu(bmp[(ret & 0x3fff) >> 5]) \| ~(((1 << n) - 1) << (ret & 0x1f))) != 0xffffffff)) {
1da177e4 LT	182	hpfs_error(s, "Allocation doesn't work! Wanted %d, allocated at %08x", n, ret);
	183	ret = 0;
	184	goto b;
	185	}
0b69760b	186	bmp[(ret & 0x3fff) >> 5] &= cpu_to_le32(~(((1 << n) - 1) << (ret & 0x1f)));
1da177e4 LT	187	hpfs_mark_4buffers_dirty(&qbh);
	188	}
	189	b:
	190	hpfs_brelse4(&qbh);
	191	uls:
1da177e4 LT	192	return ret;
	193	}
	194
	195	/*
	196	* Allocation strategy: 1) search place near the sector specified
	197	* 2) search bitmap where free sectors last found
	198	* 3) search all bitmaps
	199	* 4) search all bitmaps ignoring number of pre-allocated
	200	* sectors
	201	*/
	202
7d23ce36	203	secno hpfs_alloc_sector(struct super_block *s, secno near, unsigned n, int forward)
1da177e4 LT	204	{
	205	secno sec;
	206	int i;
	207	unsigned n_bmps;
	208	struct hpfs_sb_info *sbi = hpfs_sb(s);
	209	int f_p = 0;
	210	int near_bmp;
	211	if (forward < 0) {
	212	forward = -forward;
	213	f_p = 1;
	214	}
1da177e4 LT	215	n_bmps = (sbi->sb_fs_size + 0x4000 - 1) >> 14;
	216	if (near && near < sbi->sb_fs_size) {
	217	if ((sec = alloc_in_bmp(s, near, n, f_p ? forward : forward/4))) goto ret;
	218	near_bmp = near >> 14;
	219	} else near_bmp = n_bmps / 2;
	220	/*
	221	if (b != -1) {
	222	if ((sec = alloc_in_bmp(s, b<<14, n, f_p ? forward : forward/2))) {
	223	b &= 0x0fffffff;
	224	goto ret;
	225	}
	226	if (b > 0x10000000) if ((sec = alloc_in_bmp(s, (b&0xfffffff)<<14, n, f_p ? forward : 0))) goto ret;
	227	*/
	228	if (!f_p) if (forward > sbi->sb_max_fwd_alloc) forward = sbi->sb_max_fwd_alloc;
	229	less_fwd:
	230	for (i = 0; i < n_bmps; i++) {
	231	if (near_bmp+i < n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i) << 14, n, forward)))) {
	232	sbi->sb_c_bitmap = near_bmp+i;
	233	goto ret;
	234	}
	235	if (!forward) {
	236	if (near_bmp-i-1 >= 0 && ((sec = alloc_in_bmp(s, (near_bmp-i-1) << 14, n, forward)))) {
	237	sbi->sb_c_bitmap = near_bmp-i-1;
	238	goto ret;
	239	}
	240	} else {
	241	if (near_bmp+i >= n_bmps && ((sec = alloc_in_bmp(s, (near_bmp+i-n_bmps) << 14, n, forward)))) {
	242	sbi->sb_c_bitmap = near_bmp+i-n_bmps;
	243	goto ret;
	244	}
	245	}
	246	if (i == 1 && sbi->sb_c_bitmap != -1 && ((sec = alloc_in_bmp(s, (sbi->sb_c_bitmap) << 14, n, forward)))) {
	247	goto ret;
	248	}
	249	}
	250	if (!f_p) {
	251	if (forward) {
	252	sbi->sb_max_fwd_alloc = forward * 3 / 4;
	253	forward /= 2;
	254	goto less_fwd;
	255	}
	256	}
	257	sec = 0;
	258	ret:
2cbe5c76 MP	259	if (sec) {
	260	i = 0;
	261	do
	262	hpfs_claim_alloc(s, sec + i);
	263	while (unlikely(++i < n));
	264	}
1da177e4 LT	265	if (sec && f_p) {
1da177e4 LT	266	for (i = 0; i < forward; i++) {
2cbe5c76	267	if (!hpfs_alloc_if_possible(s, sec + n + i)) {
1da177e4 LT	268	hpfs_error(s, "Prealloc doesn't work! Wanted %d, allocated at %08x, can't allocate %d", forward, sec, i);
	269	sec = 0;
	270	break;
	271	}
	272	}
	273	}
1da177e4 LT	274	return sec;
	275	}
	276
7d23ce36	277	static secno alloc_in_dirband(struct super_block *s, secno near)
1da177e4 LT	278	{
	279	unsigned nr = near;
	280	secno sec;
	281	struct hpfs_sb_info *sbi = hpfs_sb(s);
	282	if (nr < sbi->sb_dirband_start)
	283	nr = sbi->sb_dirband_start;
	284	if (nr >= sbi->sb_dirband_start + sbi->sb_dirband_size)
	285	nr = sbi->sb_dirband_start + sbi->sb_dirband_size - 4;
	286	nr -= sbi->sb_dirband_start;
	287	nr >>= 2;
1da177e4	288	sec = alloc_in_bmp(s, (~0x3fff) \| nr, 1, 0);
1da177e4	289	if (!sec) return 0;
2cbe5c76	290	hpfs_claim_dirband_alloc(s, sec);
1da177e4 LT	291	return ((sec & 0x3fff) << 2) + sbi->sb_dirband_start;
	292	}
	293
	294	/* Alloc sector if it's free */
	295
7d23ce36	296	int hpfs_alloc_if_possible(struct super_block *s, secno sec)
1da177e4 LT	297	{
1da177e4 LT	298	struct quad_buffer_head qbh;
52576da3	299	__le32 *bmp;
1da177e4	300	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "aip"))) goto end;
0b69760b MP	301	if (le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) & (1 << (sec & 0x1f))) {
0b69760b MP	302	bmp[(sec & 0x3fff) >> 5] &= cpu_to_le32(~(1 << (sec & 0x1f)));
1da177e4 LT	303	hpfs_mark_4buffers_dirty(&qbh);
1da177e4 LT	304	hpfs_brelse4(&qbh);
2cbe5c76	305	hpfs_claim_alloc(s, sec);
1da177e4 LT	306	return 1;
	307	}
	308	hpfs_brelse4(&qbh);
	309	end:
1da177e4 LT	310	return 0;
	311	}
	312
1da177e4 LT	313	/* Free sectors in bitmaps */
	314
	315	void hpfs_free_sectors(struct super_block *s, secno sec, unsigned n)
	316	{
	317	struct quad_buffer_head qbh;
52576da3	318	__le32 *bmp;
1da177e4	319	struct hpfs_sb_info *sbi = hpfs_sb(s);
b7cb1ce2	320	/pr_info("2 - ");/
1da177e4 LT	321	if (!n) return;
	322	if (sec < 0x12) {
	323	hpfs_error(s, "Trying to free reserved sector %08x", sec);
	324	return;
	325	}
1da177e4 LT	326	sbi->sb_max_fwd_alloc += n > 0xffff ? 0xffff : n;
	327	if (sbi->sb_max_fwd_alloc > 0xffffff) sbi->sb_max_fwd_alloc = 0xffffff;
	328	new_map:
	329	if (!(bmp = hpfs_map_bitmap(s, sec >> 14, &qbh, "free"))) {
1da177e4 LT	330	return;
	331	}
	332	new_tst:
0b69760b	333	if ((le32_to_cpu(bmp[(sec & 0x3fff) >> 5]) >> (sec & 0x1f) & 1)) {
1da177e4 LT	334	hpfs_error(s, "sector %08x not allocated", sec);
1da177e4 LT	335	hpfs_brelse4(&qbh);
1da177e4 LT	336	return;
1da177e4 LT	337	}
0b69760b	338	bmp[(sec & 0x3fff) >> 5] \|= cpu_to_le32(1 << (sec & 0x1f));
2cbe5c76	339	hpfs_claim_free(s, sec);
1da177e4 LT	340	if (!--n) {
	341	hpfs_mark_4buffers_dirty(&qbh);
	342	hpfs_brelse4(&qbh);
1da177e4 LT	343	return;
	344	}
	345	if (!(++sec & 0x3fff)) {
	346	hpfs_mark_4buffers_dirty(&qbh);
	347	hpfs_brelse4(&qbh);
	348	goto new_map;
	349	}
	350	goto new_tst;
	351	}
	352
	353	/*
	354	* Check if there are at least n free dnodes on the filesystem.
	355	* Called before adding to dnode. If we run out of space while
	356	* splitting dnodes, it would corrupt dnode tree.
	357	*/
	358
	359	int hpfs_check_free_dnodes(struct super_block *s, int n)
	360	{
	361	int n_bmps = (hpfs_sb(s)->sb_fs_size + 0x4000 - 1) >> 14;
	362	int b = hpfs_sb(s)->sb_c_bitmap & 0x0fffffff;
	363	int i, j;
52576da3	364	__le32 *bmp;
1da177e4 LT	365	struct quad_buffer_head qbh;
	366	if ((bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
	367	for (j = 0; j < 512; j++) {
	368	unsigned k;
0b69760b MP	369	if (!le32_to_cpu(bmp[j])) continue;
0b69760b MP	370	for (k = le32_to_cpu(bmp[j]); k; k >>= 1) if (k & 1) if (!--n) {
1da177e4 LT	371	hpfs_brelse4(&qbh);
	372	return 0;
	373	}
	374	}
	375	}
	376	hpfs_brelse4(&qbh);
	377	i = 0;
	378	if (hpfs_sb(s)->sb_c_bitmap != -1) {
	379	bmp = hpfs_map_bitmap(s, b, &qbh, "chkdn1");
	380	goto chk_bmp;
	381	}
	382	chk_next:
	383	if (i == b) i++;
	384	if (i >= n_bmps) return 1;
	385	bmp = hpfs_map_bitmap(s, i, &qbh, "chkdn2");
	386	chk_bmp:
	387	if (bmp) {
	388	for (j = 0; j < 512; j++) {
0b69760b MP	389	u32 k;
0b69760b MP	390	if (!le32_to_cpu(bmp[j])) continue;
1da177e4	391	for (k = 0xf; k; k <<= 4)
0b69760b	392	if ((le32_to_cpu(bmp[j]) & k) == k) {
1da177e4 LT	393	if (!--n) {
	394	hpfs_brelse4(&qbh);
	395	return 0;
	396	}
	397	}
	398	}
	399	hpfs_brelse4(&qbh);
	400	}
	401	i++;
	402	goto chk_next;
	403	}
	404
	405	void hpfs_free_dnode(struct super_block *s, dnode_secno dno)
	406	{
	407	if (hpfs_sb(s)->sb_chk) if (dno & 3) {
	408	hpfs_error(s, "hpfs_free_dnode: dnode %08x not aligned", dno);
	409	return;
	410	}
	411	if (dno < hpfs_sb(s)->sb_dirband_start \|\|
	412	dno >= hpfs_sb(s)->sb_dirband_start + hpfs_sb(s)->sb_dirband_size) {
	413	hpfs_free_sectors(s, dno, 4);
	414	} else {
	415	struct quad_buffer_head qbh;
52576da3	416	__le32 *bmp;
1da177e4	417	unsigned ssec = (dno - hpfs_sb(s)->sb_dirband_start) / 4;
1da177e4	418	if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
1da177e4 LT	419	return;
1da177e4 LT	420	}
0b69760b	421	bmp[ssec >> 5] \|= cpu_to_le32(1 << (ssec & 0x1f));
1da177e4 LT	422	hpfs_mark_4buffers_dirty(&qbh);
1da177e4 LT	423	hpfs_brelse4(&qbh);
2cbe5c76	424	hpfs_claim_dirband_free(s, dno);
1da177e4 LT	425	}
	426	}
	427
	428	struct dnode hpfs_alloc_dnode(struct super_block s, secno near,
7d23ce36	429	dnode_secno dno, struct quad_buffer_head qbh)
1da177e4 LT	430	{
1da177e4 LT	431	struct dnode *d;
2cbe5c76	432	if (hpfs_get_free_dnodes(s) > FREE_DNODES_ADD) {
7d23ce36 MP	433	if (!(*dno = alloc_in_dirband(s, near)))
7d23ce36 MP	434	if (!(*dno = hpfs_alloc_sector(s, near, 4, 0))) return NULL;
1da177e4	435	} else {
7d23ce36 MP	436	if (!(*dno = hpfs_alloc_sector(s, near, 4, 0)))
7d23ce36 MP	437	if (!(*dno = alloc_in_dirband(s, near))) return NULL;
1da177e4 LT	438	}
	439	if (!(d = hpfs_get_4sectors(s, *dno, qbh))) {
	440	hpfs_free_dnode(s, *dno);
	441	return NULL;
	442	}
	443	memset(d, 0, 2048);
0b69760b MP	444	d->magic = cpu_to_le32(DNODE_MAGIC);
0b69760b MP	445	d->first_free = cpu_to_le32(52);
1da177e4 LT	446	d->dirent[0] = 32;
	447	d->dirent[2] = 8;
	448	d->dirent[30] = 1;
	449	d->dirent[31] = 255;
0b69760b	450	d->self = cpu_to_le32(*dno);
1da177e4 LT	451	return d;
	452	}
	453
	454	struct fnode hpfs_alloc_fnode(struct super_block s, secno near, fnode_secno *fno,
	455	struct buffer_head **bh)
	456	{
	457	struct fnode *f;
7d23ce36	458	if (!(*fno = hpfs_alloc_sector(s, near, 1, FNODE_ALLOC_FWD))) return NULL;
1da177e4 LT	459	if (!(f = hpfs_get_sector(s, *fno, bh))) {
	460	hpfs_free_sectors(s, *fno, 1);
	461	return NULL;
	462	}
	463	memset(f, 0, 512);
0b69760b MP	464	f->magic = cpu_to_le32(FNODE_MAGIC);
0b69760b MP	465	f->ea_offs = cpu_to_le16(0xc4);
1da177e4	466	f->btree.n_free_nodes = 8;
0b69760b	467	f->btree.first_free = cpu_to_le16(8);
1da177e4 LT	468	return f;
	469	}
	470
	471	struct anode hpfs_alloc_anode(struct super_block s, secno near, anode_secno *ano,
	472	struct buffer_head **bh)
	473	{
	474	struct anode *a;
7d23ce36	475	if (!(*ano = hpfs_alloc_sector(s, near, 1, ANODE_ALLOC_FWD))) return NULL;
1da177e4 LT	476	if (!(a = hpfs_get_sector(s, *ano, bh))) {
	477	hpfs_free_sectors(s, *ano, 1);
	478	return NULL;
	479	}
	480	memset(a, 0, 512);
0b69760b MP	481	a->magic = cpu_to_le32(ANODE_MAGIC);
0b69760b MP	482	a->self = cpu_to_le32(*ano);
1da177e4 LT	483	a->btree.n_free_nodes = 40;
1da177e4 LT	484	a->btree.n_used_nodes = 0;
0b69760b	485	a->btree.first_free = cpu_to_le16(8);
1da177e4 LT	486	return a;
1da177e4 LT	487	}
a27b5b97 MP	488
	489	static unsigned find_run(__le32 bmp, unsigned idx)
	490	{
	491	unsigned len;
	492	while (tstbits(bmp, *idx, 1)) {
	493	(*idx)++;
	494	if (unlikely(*idx >= 0x4000))
	495	return 0;
	496	}
	497	len = 1;
	498	while (!tstbits(bmp, *idx + len, 1))
	499	len++;
	500	return len;
	501	}
	502
	503	static int do_trim(struct super_block s, secno start, unsigned len, secno limit_start, secno limit_end, unsigned minlen, unsigned result)
	504	{
	505	int err;
	506	secno end;
	507	if (fatal_signal_pending(current))
	508	return -EINTR;
	509	end = start + len;
	510	if (start < limit_start)
	511	start = limit_start;
	512	if (end > limit_end)
	513	end = limit_end;
	514	if (start >= end)
	515	return 0;
	516	if (end - start < minlen)
	517	return 0;
	518	err = sb_issue_discard(s, start, end - start, GFP_NOFS, 0);
	519	if (err)
	520	return err;
	521	*result += end - start;
	522	return 0;
	523	}
	524
	525	int hpfs_trim_fs(struct super_block s, u64 start, u64 end, u64 minlen, unsigned result)
	526	{
	527	int err = 0;
	528	struct hpfs_sb_info *sbi = hpfs_sb(s);
	529	unsigned idx, len, start_bmp, end_bmp;
	530	__le32 *bmp;
	531	struct quad_buffer_head qbh;
	532
	533	*result = 0;
	534	if (!end \|\| end > sbi->sb_fs_size)
	535	end = sbi->sb_fs_size;
	536	if (start >= sbi->sb_fs_size)
	537	return 0;
	538	if (minlen > 0x4000)
	539	return 0;
	540	if (start < sbi->sb_dirband_start + sbi->sb_dirband_size && end > sbi->sb_dirband_start) {
	541	hpfs_lock(s);
bc98a42c	542	if (sb_rdonly(s)) {
a27b5b97 MP	543	err = -EROFS;
	544	goto unlock_1;
	545	}
	546	if (!(bmp = hpfs_map_dnode_bitmap(s, &qbh))) {
	547	err = -EIO;
	548	goto unlock_1;
	549	}
	550	idx = 0;
	551	while ((len = find_run(bmp, &idx)) && !err) {
	552	err = do_trim(s, sbi->sb_dirband_start + idx * 4, len * 4, start, end, minlen, result);
	553	idx += len;
	554	}
	555	hpfs_brelse4(&qbh);
	556	unlock_1:
	557	hpfs_unlock(s);
	558	}
	559	start_bmp = start >> 14;
	560	end_bmp = (end + 0x3fff) >> 14;
	561	while (start_bmp < end_bmp && !err) {
	562	hpfs_lock(s);
bc98a42c	563	if (sb_rdonly(s)) {
a27b5b97 MP	564	err = -EROFS;
	565	goto unlock_2;
	566	}
	567	if (!(bmp = hpfs_map_bitmap(s, start_bmp, &qbh, "trim"))) {
	568	err = -EIO;
	569	goto unlock_2;
	570	}
	571	idx = 0;
	572	while ((len = find_run(bmp, &idx)) && !err) {
	573	err = do_trim(s, (start_bmp << 14) + idx, len, start, end, minlen, result);
	574	idx += len;
	575	}
	576	hpfs_brelse4(&qbh);
	577	unlock_2:
	578	hpfs_unlock(s);
	579	start_bmp++;
	580	}
	581	return err;
	582	}