[linux.git] / fs / hpfs / alloc.c

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