[linux-2.6-block.git] / fs / hpfs / map.c

/*
 *  linux/fs/hpfs/map.c
 *
 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
 *
 *  mapping structures to memory with some minimal checks
 */

#include "hpfs_fn.h"

__le32 *hpfs_map_dnode_bitmap(struct super_block *s, struct quad_buffer_head *qbh)
{
	return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
}

__le32 *hpfs_map_bitmap(struct super_block *s, unsigned bmp_block,
			 struct quad_buffer_head *qbh, char *id)
{
	secno sec;
	__le32 *ret;
	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
	if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
		hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
		return NULL;
	}
	sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
	if (!sec || sec > hpfs_sb(s)->sb_fs_size-4) {
		hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
		return NULL;
	}
	ret = hpfs_map_4sectors(s, sec, qbh, 4);
	if (ret) hpfs_prefetch_bitmap(s, bmp_block + 1);
	return ret;
}

void hpfs_prefetch_bitmap(struct super_block *s, unsigned bmp_block)
{
	unsigned to_prefetch, next_prefetch;
	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
	if (unlikely(bmp_block >= n_bands))
		return;
	to_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
	if (unlikely(bmp_block + 1 >= n_bands))
		next_prefetch = 0;
	else
		next_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block + 1]);
	hpfs_prefetch_sectors(s, to_prefetch, 4 + 4 * (to_prefetch + 4 == next_prefetch));
}

/*
 * Load first code page into kernel memory, return pointer to 256-byte array,
 * first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
 * lowercasing table
 */

unsigned char *hpfs_load_code_page(struct super_block *s, secno cps)
{
	struct buffer_head *bh;
	secno cpds;
	unsigned cpi;
	unsigned char *ptr;
	unsigned char *cp_table;
	int i;
	struct code_page_data *cpd;
	struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
	if (!cp) return NULL;
	if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
		pr_err("Code page directory magic doesn't match (magic = %08x)\n",
			le32_to_cpu(cp->magic));
		brelse(bh);
		return NULL;
	}
	if (!le32_to_cpu(cp->n_code_pages)) {
		pr_err("n_code_pages == 0\n");
		brelse(bh);
		return NULL;
	}
	cpds = le32_to_cpu(cp->array[0].code_page_data);
	cpi = le16_to_cpu(cp->array[0].index);
	brelse(bh);

	if (cpi >= 3) {
		pr_err("Code page index out of array\n");
		return NULL;
	}
	
	if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
	if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
		pr_err("Code page index out of sector\n");
		brelse(bh);
		return NULL;
	}
	ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
	if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
		pr_err("out of memory for code page table\n");
		brelse(bh);
		return NULL;
	}
	memcpy(cp_table, ptr, 128);
	brelse(bh);

	/* Try to build lowercasing table from uppercasing one */

	for (i=128; i<256; i++) cp_table[i]=i;
	for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
		cp_table[cp_table[i-128]] = i;
	
	return cp_table;
}

__le32 *hpfs_load_bitmap_directory(struct super_block *s, secno bmp)
{
	struct buffer_head *bh;
	int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
	int i;
	__le32 *b;
	if (!(b = kmalloc(n * 512, GFP_KERNEL))) {
		pr_err("can't allocate memory for bitmap directory\n");
		return NULL;
	}	
	for (i=0;i<n;i++) {
		__le32 *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
		if (!d) {
			kfree(b);
			return NULL;
		}
		memcpy((char *)b + 512 * i, d, 512);
		brelse(bh);
	}
	return b;
}

/*
 * Load fnode to memory
 */

struct fnode *hpfs_map_fnode(struct super_block *s, ino_t ino, struct buffer_head **bhp)
{
	struct fnode *fnode;
	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
		return NULL;
	}
	if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
		if (hpfs_sb(s)->sb_chk) {
			struct extended_attribute *ea;
			struct extended_attribute *ea_end;
			if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
				hpfs_error(s, "bad magic on fnode %08lx",
					(unsigned long)ino);
				goto bail;
			}
			if (!fnode_is_dir(fnode)) {
				if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
				    (bp_internal(&fnode->btree) ? 12 : 8)) {
					hpfs_error(s,
					   "bad number of nodes in fnode %08lx",
					    (unsigned long)ino);
					goto bail;
				}
				if (le16_to_cpu(fnode->btree.first_free) !=
				    8 + fnode->btree.n_used_nodes * (bp_internal(&fnode->btree) ? 8 : 12)) {
					hpfs_error(s,
					    "bad first_free pointer in fnode %08lx",
					    (unsigned long)ino);
					goto bail;
				}
			}
			if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 ||
			   le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) {
				hpfs_error(s,
					"bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
					(unsigned long)ino,
					le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
				goto bail;
			}
			ea = fnode_ea(fnode);
			ea_end = fnode_end_ea(fnode);
			while (ea != ea_end) {
				if (ea > ea_end) {
					hpfs_error(s, "bad EA in fnode %08lx",
						(unsigned long)ino);
					goto bail;
				}
				ea = next_ea(ea);
			}
		}
	}
	return fnode;
	bail:
	brelse(*bhp);
	return NULL;
}

struct anode *hpfs_map_anode(struct super_block *s, anode_secno ano, struct buffer_head **bhp)
{
	struct anode *anode;
	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
	if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
		if (hpfs_sb(s)->sb_chk) {
			if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
				hpfs_error(s, "bad magic on anode %08x", ano);
				goto bail;
			}
			if (le32_to_cpu(anode->self) != ano) {
				hpfs_error(s, "self pointer invalid on anode %08x", ano);
				goto bail;
			}
			if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
			    (bp_internal(&anode->btree) ? 60 : 40)) {
				hpfs_error(s, "bad number of nodes in anode %08x", ano);
				goto bail;
			}
			if (le16_to_cpu(anode->btree.first_free) !=
			    8 + anode->btree.n_used_nodes * (bp_internal(&anode->btree) ? 8 : 12)) {
				hpfs_error(s, "bad first_free pointer in anode %08x", ano);
				goto bail;
			}
		}
	return anode;
	bail:
	brelse(*bhp);
	return NULL;
}

/*
 * Load dnode to memory and do some checks
 */

struct dnode *hpfs_map_dnode(struct super_block *s, unsigned secno,
			     struct quad_buffer_head *qbh)
{
	struct dnode *dnode;
	if (hpfs_sb(s)->sb_chk) {
		if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
		if (secno & 3) {
			hpfs_error(s, "dnode %08x not byte-aligned", secno);
			return NULL;
		}	
	}
	if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
		if (hpfs_sb(s)->sb_chk) {
			unsigned p, pp = 0;
			unsigned char *d = (unsigned char *)dnode;
			int b = 0;
			if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
				hpfs_error(s, "bad magic on dnode %08x", secno);
				goto bail;
			}
			if (le32_to_cpu(dnode->self) != secno)
				hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
			/* Check dirents - bad dirents would cause infinite
			   loops or shooting to memory */
			if (le32_to_cpu(dnode->first_free) > 2048) {
				hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
				goto bail;
			}
			for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
				struct hpfs_dirent *de = (struct hpfs_dirent *)((char *)dnode + p);
				if (le16_to_cpu(de->length) > 292 || (le16_to_cpu(de->length) < 32) || (le16_to_cpu(de->length) & 3) || p + le16_to_cpu(de->length) > 2048) {
					hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
					if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & MS_RDONLY) goto ok;
					hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				ok:
				if (hpfs_sb(s)->sb_chk >= 2) b |= 1 << de->down;
				if (de->down) if (de_down_pointer(de) < 0x10) {
					hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
					goto bail;
				}
				pp = p;
				
			}
			if (p != le32_to_cpu(dnode->first_free)) {
				hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
				goto bail;
			}
			if (d[pp + 30] != 1 || d[pp + 31] != 255) {
				hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
				goto bail;
			}
			if (b == 3)
				pr_err("unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n",
					secno);
		}
	return dnode;
	bail:
	hpfs_brelse4(qbh);
	return NULL;
}

dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
{
	struct buffer_head *bh;
	struct fnode *fnode;
	dnode_secno dno;

	fnode = hpfs_map_fnode(s, ino, &bh);
	if (!fnode)
		return 0;

	dno = le32_to_cpu(fnode->u.external[0].disk_secno);
	brelse(bh);
	return dno;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/hpfs/map.c
	3	*
	4	* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
	5	*
	6	* mapping structures to memory with some minimal checks
	7	*/
	8
	9	#include "hpfs_fn.h"
	10
52576da3	11	__le32 hpfs_map_dnode_bitmap(struct super_block s, struct quad_buffer_head *qbh)
1da177e4 LT	12	{
	13	return hpfs_map_4sectors(s, hpfs_sb(s)->sb_dmap, qbh, 0);
	14	}
	15
52576da3	16	__le32 hpfs_map_bitmap(struct super_block s, unsigned bmp_block,
1da177e4 LT	17	struct quad_buffer_head qbh, char id)
	18	{
	19	secno sec;
275f495d	20	__le32 *ret;
3ebacb05 MP	21	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
3ebacb05 MP	22	if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
1da177e4 LT	23	hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x at %s", bmp_block, id);
	24	return NULL;
	25	}
0b69760b	26	sec = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
1da177e4 LT	27	if (!sec \|\| sec > hpfs_sb(s)->sb_fs_size-4) {
	28	hpfs_error(s, "invalid bitmap block pointer %08x -> %08x at %s", bmp_block, sec, id);
	29	return NULL;
	30	}
275f495d MP	31	ret = hpfs_map_4sectors(s, sec, qbh, 4);
	32	if (ret) hpfs_prefetch_bitmap(s, bmp_block + 1);
	33	return ret;
	34	}
	35
	36	void hpfs_prefetch_bitmap(struct super_block *s, unsigned bmp_block)
	37	{
	38	unsigned to_prefetch, next_prefetch;
	39	unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
	40	if (unlikely(bmp_block >= n_bands))
	41	return;
	42	to_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block]);
	43	if (unlikely(bmp_block + 1 >= n_bands))
	44	next_prefetch = 0;
	45	else
	46	next_prefetch = le32_to_cpu(hpfs_sb(s)->sb_bmp_dir[bmp_block + 1]);
	47	hpfs_prefetch_sectors(s, to_prefetch, 4 + 4 * (to_prefetch + 4 == next_prefetch));
1da177e4 LT	48	}
	49
	50	/*
	51	* Load first code page into kernel memory, return pointer to 256-byte array,
	52	* first 128 bytes are uppercasing table for chars 128-255, next 128 bytes are
	53	* lowercasing table
	54	*/
	55
7e7742ee	56	unsigned char hpfs_load_code_page(struct super_block s, secno cps)
1da177e4 LT	57	{
	58	struct buffer_head *bh;
	59	secno cpds;
	60	unsigned cpi;
	61	unsigned char *ptr;
	62	unsigned char *cp_table;
	63	int i;
	64	struct code_page_data *cpd;
	65	struct code_page_directory *cp = hpfs_map_sector(s, cps, &bh, 0);
	66	if (!cp) return NULL;
0b69760b	67	if (le32_to_cpu(cp->magic) != CP_DIR_MAGIC) {
a19189e5	68	pr_err("Code page directory magic doesn't match (magic = %08x)\n",
b7cb1ce2	69	le32_to_cpu(cp->magic));
1da177e4 LT	70	brelse(bh);
	71	return NULL;
	72	}
0b69760b	73	if (!le32_to_cpu(cp->n_code_pages)) {
a19189e5	74	pr_err("n_code_pages == 0\n");
1da177e4 LT	75	brelse(bh);
	76	return NULL;
	77	}
0b69760b MP	78	cpds = le32_to_cpu(cp->array[0].code_page_data);
0b69760b MP	79	cpi = le16_to_cpu(cp->array[0].index);
1da177e4 LT	80	brelse(bh);
	81
	82	if (cpi >= 3) {
a19189e5	83	pr_err("Code page index out of array\n");
1da177e4 LT	84	return NULL;
	85	}
	86
	87	if (!(cpd = hpfs_map_sector(s, cpds, &bh, 0))) return NULL;
0b69760b	88	if (le16_to_cpu(cpd->offs[cpi]) > 0x178) {
a19189e5	89	pr_err("Code page index out of sector\n");
1da177e4 LT	90	brelse(bh);
	91	return NULL;
	92	}
0b69760b	93	ptr = (unsigned char *)cpd + le16_to_cpu(cpd->offs[cpi]) + 6;
1da177e4	94	if (!(cp_table = kmalloc(256, GFP_KERNEL))) {
a19189e5	95	pr_err("out of memory for code page table\n");
1da177e4 LT	96	brelse(bh);
	97	return NULL;
	98	}
	99	memcpy(cp_table, ptr, 128);
	100	brelse(bh);
	101
	102	/* Try to build lowercasing table from uppercasing one */
	103
	104	for (i=128; i<256; i++) cp_table[i]=i;
	105	for (i=128; i<256; i++) if (cp_table[i-128]!=i && cp_table[i-128]>=128)
	106	cp_table[cp_table[i-128]] = i;
	107
	108	return cp_table;
	109	}
	110
28fe3c19	111	__le32 hpfs_load_bitmap_directory(struct super_block s, secno bmp)
1da177e4 LT	112	{
	113	struct buffer_head *bh;
	114	int n = (hpfs_sb(s)->sb_fs_size + 0x200000 - 1) >> 21;
	115	int i;
28fe3c19	116	__le32 *b;
1da177e4	117	if (!(b = kmalloc(n * 512, GFP_KERNEL))) {
a19189e5	118	pr_err("can't allocate memory for bitmap directory\n");
1da177e4 LT	119	return NULL;
	120	}
	121	for (i=0;i<n;i++) {
28fe3c19	122	__le32 *d = hpfs_map_sector(s, bmp+i, &bh, n - i - 1);
1da177e4 LT	123	if (!d) {
	124	kfree(b);
	125	return NULL;
	126	}
	127	memcpy((char )b + 512 i, d, 512);
	128	brelse(bh);
	129	}
	130	return b;
	131	}
	132
	133	/*
	134	* Load fnode to memory
	135	*/
	136
	137	struct fnode hpfs_map_fnode(struct super_block s, ino_t ino, struct buffer_head **bhp)
	138	{
	139	struct fnode *fnode;
	140	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ino, 1, "fnode")) {
	141	return NULL;
	142	}
	143	if ((fnode = hpfs_map_sector(s, ino, bhp, FNODE_RD_AHEAD))) {
	144	if (hpfs_sb(s)->sb_chk) {
	145	struct extended_attribute *ea;
	146	struct extended_attribute *ea_end;
0b69760b	147	if (le32_to_cpu(fnode->magic) != FNODE_MAGIC) {
18debbbc RD	148	hpfs_error(s, "bad magic on fnode %08lx",
18debbbc RD	149	(unsigned long)ino);
1da177e4 LT	150	goto bail;
1da177e4 LT	151	}
c4c99543	152	if (!fnode_is_dir(fnode)) {
1da177e4	153	if ((unsigned)fnode->btree.n_used_nodes + (unsigned)fnode->btree.n_free_nodes !=
ddc19e6e	154	(bp_internal(&fnode->btree) ? 12 : 8)) {
18debbbc RD	155	hpfs_error(s,
	156	"bad number of nodes in fnode %08lx",
	157	(unsigned long)ino);
1da177e4 LT	158	goto bail;
1da177e4 LT	159	}
0b69760b	160	if (le16_to_cpu(fnode->btree.first_free) !=
ddc19e6e	161	8 + fnode->btree.n_used_nodes * (bp_internal(&fnode->btree) ? 8 : 12)) {
18debbbc RD	162	hpfs_error(s,
	163	"bad first_free pointer in fnode %08lx",
	164	(unsigned long)ino);
1da177e4 LT	165	goto bail;
	166	}
	167	}
0b69760b MP	168	if (le16_to_cpu(fnode->ea_size_s) && (le16_to_cpu(fnode->ea_offs) < 0xc4 \|\|
0b69760b MP	169	le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s) > 0x200)) {
18debbbc RD	170	hpfs_error(s,
	171	"bad EA info in fnode %08lx: ea_offs == %04x ea_size_s == %04x",
	172	(unsigned long)ino,
0b69760b	173	le16_to_cpu(fnode->ea_offs), le16_to_cpu(fnode->ea_size_s));
1da177e4 LT	174	goto bail;
	175	}
	176	ea = fnode_ea(fnode);
	177	ea_end = fnode_end_ea(fnode);
	178	while (ea != ea_end) {
	179	if (ea > ea_end) {
18debbbc RD	180	hpfs_error(s, "bad EA in fnode %08lx",
18debbbc RD	181	(unsigned long)ino);
1da177e4 LT	182	goto bail;
	183	}
	184	ea = next_ea(ea);
	185	}
	186	}
	187	}
	188	return fnode;
	189	bail:
	190	brelse(*bhp);
	191	return NULL;
	192	}
	193
	194	struct anode hpfs_map_anode(struct super_block s, anode_secno ano, struct buffer_head **bhp)
	195	{
	196	struct anode *anode;
	197	if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, ano, 1, "anode")) return NULL;
	198	if ((anode = hpfs_map_sector(s, ano, bhp, ANODE_RD_AHEAD)))
	199	if (hpfs_sb(s)->sb_chk) {
0b69760b	200	if (le32_to_cpu(anode->magic) != ANODE_MAGIC) {
1da177e4 LT	201	hpfs_error(s, "bad magic on anode %08x", ano);
	202	goto bail;
	203	}
0b69760b MP	204	if (le32_to_cpu(anode->self) != ano) {
	205	hpfs_error(s, "self pointer invalid on anode %08x", ano);
	206	goto bail;
	207	}
1da177e4	208	if ((unsigned)anode->btree.n_used_nodes + (unsigned)anode->btree.n_free_nodes !=
ddc19e6e	209	(bp_internal(&anode->btree) ? 60 : 40)) {
1da177e4 LT	210	hpfs_error(s, "bad number of nodes in anode %08x", ano);
	211	goto bail;
	212	}
0b69760b	213	if (le16_to_cpu(anode->btree.first_free) !=
ddc19e6e	214	8 + anode->btree.n_used_nodes * (bp_internal(&anode->btree) ? 8 : 12)) {
1da177e4 LT	215	hpfs_error(s, "bad first_free pointer in anode %08x", ano);
	216	goto bail;
	217	}
	218	}
	219	return anode;
	220	bail:
	221	brelse(*bhp);
	222	return NULL;
	223	}
	224
	225	/*
	226	* Load dnode to memory and do some checks
	227	*/
	228
	229	struct dnode hpfs_map_dnode(struct super_block s, unsigned secno,
	230	struct quad_buffer_head *qbh)
	231	{
	232	struct dnode *dnode;
	233	if (hpfs_sb(s)->sb_chk) {
	234	if (hpfs_chk_sectors(s, secno, 4, "dnode")) return NULL;
	235	if (secno & 3) {
	236	hpfs_error(s, "dnode %08x not byte-aligned", secno);
	237	return NULL;
	238	}
	239	}
	240	if ((dnode = hpfs_map_4sectors(s, secno, qbh, DNODE_RD_AHEAD)))
	241	if (hpfs_sb(s)->sb_chk) {
	242	unsigned p, pp = 0;
7e7742ee	243	unsigned char d = (unsigned char )dnode;
1da177e4	244	int b = 0;
0b69760b	245	if (le32_to_cpu(dnode->magic) != DNODE_MAGIC) {
1da177e4 LT	246	hpfs_error(s, "bad magic on dnode %08x", secno);
	247	goto bail;
	248	}
0b69760b MP	249	if (le32_to_cpu(dnode->self) != secno)
0b69760b MP	250	hpfs_error(s, "bad self pointer on dnode %08x self = %08x", secno, le32_to_cpu(dnode->self));
1da177e4 LT	251	/* Check dirents - bad dirents would cause infinite
1da177e4 LT	252	loops or shooting to memory */
0b69760b MP	253	if (le32_to_cpu(dnode->first_free) > 2048) {
0b69760b MP	254	hpfs_error(s, "dnode %08x has first_free == %08x", secno, le32_to_cpu(dnode->first_free));
1da177e4 LT	255	goto bail;
1da177e4 LT	256	}
0b69760b	257	for (p = 20; p < le32_to_cpu(dnode->first_free); p += d[p] + (d[p+1] << 8)) {
1da177e4	258	struct hpfs_dirent de = (struct hpfs_dirent )((char *)dnode + p);
0b69760b	259	if (le16_to_cpu(de->length) > 292 \|\| (le16_to_cpu(de->length) < 32) \|\| (le16_to_cpu(de->length) & 3) \|\| p + le16_to_cpu(de->length) > 2048) {
1da177e4 LT	260	hpfs_error(s, "bad dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
	261	goto bail;
	262	}
0b69760b MP	263	if (((31 + de->namelen + de->down*4 + 3) & ~3) != le16_to_cpu(de->length)) {
0b69760b MP	264	if (((31 + de->namelen + de->down*4 + 3) & ~3) < le16_to_cpu(de->length) && s->s_flags & MS_RDONLY) goto ok;
1da177e4 LT	265	hpfs_error(s, "namelen does not match dirent size in dnode %08x, dirent %03x, last %03x", secno, p, pp);
	266	goto bail;
	267	}
	268	ok:
	269	if (hpfs_sb(s)->sb_chk >= 2) b \|= 1 << de->down;
	270	if (de->down) if (de_down_pointer(de) < 0x10) {
	271	hpfs_error(s, "bad down pointer in dnode %08x, dirent %03x, last %03x", secno, p, pp);
	272	goto bail;
	273	}
	274	pp = p;
	275
	276	}
0b69760b	277	if (p != le32_to_cpu(dnode->first_free)) {
1da177e4 LT	278	hpfs_error(s, "size on last dirent does not match first_free; dnode %08x", secno);
	279	goto bail;
	280	}
	281	if (d[pp + 30] != 1 \|\| d[pp + 31] != 255) {
	282	hpfs_error(s, "dnode %08x does not end with \\377 entry", secno);
	283	goto bail;
	284	}
b7cb1ce2	285	if (b == 3)
a19189e5	286	pr_err("unbalanced dnode tree, dnode %08x; see hpfs.txt 4 more info\n",
b7cb1ce2	287	secno);
1da177e4 LT	288	}
	289	return dnode;
	290	bail:
	291	hpfs_brelse4(qbh);
	292	return NULL;
	293	}
	294
	295	dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino)
	296	{
	297	struct buffer_head *bh;
	298	struct fnode *fnode;
	299	dnode_secno dno;
	300
	301	fnode = hpfs_map_fnode(s, ino, &bh);
	302	if (!fnode)
	303	return 0;
	304
0b69760b	305	dno = le32_to_cpu(fnode->u.external[0].disk_secno);
1da177e4 LT	306	brelse(bh);
	307	return dno;
	308	}