reiserfs fixes patch set

@@ -478,7 +478,7 @@ reiserfs_xattr_set(struct inode *inode, 
 	/* Resize it so we're ok to write there */
 	newattrs.ia_size = buffer_size;
 	newattrs.ia_valid = ATTR_SIZE | ATTR_CTIME;
-	mutex_lock(&xinode->i_mutex);
+	mutex_lock_nested(&xinode->i_mutex, I_MUTEX_XATTR);
 	err = notify_change(fp->f_path.dentry, &newattrs);
 	if (err)
 		goto out_filp;

@@ -1217,7 +1217,8 @@ int reiserfs_xattr_init(struct super_blo
 		if (!IS_ERR(dentry)) {
 			if (!(mount_flags & MS_RDONLY) && !dentry->d_inode) {
 				struct inode *inode = dentry->d_parent->d_inode;
-				mutex_lock(&inode->i_mutex);
+				mutex_lock_nested(&inode->i_mutex,
+				                  I_MUTEX_XATTR);
 				err = inode->i_op->mkdir(inode, dentry, 0700);
 				mutex_unlock(&inode->i_mutex);
 				if (err) {

@@ -356,13 +356,11 @@ extern struct tree_balance *cur_tb;
 void reiserfs_panic(struct super_block *sb, const char *fmt, ...)
 {
 	do_reiserfs_warning(fmt);
-	printk(KERN_EMERG "REISERFS: panic (device %s): %s\n",
-	       reiserfs_bdevname(sb), error_buf);
-	BUG();
 
-	/* this is not actually called, but makes reiserfs_panic() "noreturn" */
-	panic("REISERFS: panic (device %s): %s\n",
-	      reiserfs_bdevname(sb), error_buf);
+	dump_stack();
+
+	panic(KERN_EMERG "REISERFS: panic (device %s): %s\n",
+	       reiserfs_bdevname(sb), error_buf);
 }
 
 void reiserfs_abort(struct super_block *sb, int errno, const char *fmt, ...)

@@ -56,7 +56,6 @@ static inline void get_bit_address(struc
 	*offset = block & ((s->s_blocksize << 3) - 1);
 }
 
-#ifdef CONFIG_REISERFS_CHECK
 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
 {
 	int bmap, offset;

@@ -106,7 +105,6 @@ int is_reusable(struct super_block *s, b
 
 	return 1;
 }
-#endif				/* CONFIG_REISERFS_CHECK */
 
 /* searches in journal structures for a given block number (bmap, off). If block
    is found in reiserfs journal it suggests next free block candidate to test. */

@@ -434,12 +432,19 @@ void reiserfs_free_block(struct reiserfs
 			 int for_unformatted)
 {
 	struct super_block *s = th->t_super;
-
 	BUG_ON(!th->t_trans_id);
 
 	RFALSE(!s, "vs-4061: trying to free block on nonexistent device");
-	RFALSE(is_reusable(s, block, 1) == 0,
-	       "vs-4071: can not free such block");
+	if (!is_reusable(s, block, 1))
+		return;
+
+	if (block > sb_block_count(REISERFS_SB(s)->s_rs)) {
+		reiserfs_panic(th->t_super, "bitmap-4072",
+		               "Trying to free block outside file system "
+			       "boundaries (%lu > %lu)",
+			       block, sb_block_count(REISERFS_SB(s)->s_rs));
+		return;
+	}
 	/* mark it before we clear it, just in case */
 	journal_mark_freed(th, s, block);
 	_reiserfs_free_block(th, inode, block, for_unformatted);

@@ -449,11 +454,11 @@ void reiserfs_free_block(struct reiserfs
 static void reiserfs_free_prealloc_block(struct reiserfs_transaction_handle *th,
 					 struct inode *inode, b_blocknr_t block)
 {
+	BUG_ON(!th->t_trans_id);
 	RFALSE(!th->t_super,
 	       "vs-4060: trying to free block on nonexistent device");
-	RFALSE(is_reusable(th->t_super, block, 1) == 0,
-	       "vs-4070: can not free such block");
-	BUG_ON(!th->t_trans_id);
+	if (!is_reusable(th->t_super, block, 1))
+		return;
 	_reiserfs_free_block(th, inode, block, 1);
 }
 

@@ -47,7 +47,9 @@
     test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
 
 static inline void get_bit_address(struct super_block *s,
-				   b_blocknr_t block, int *bmap_nr, int *offset)
+				   b_blocknr_t block,
+				   unsigned int *bmap_nr,
+				   unsigned int *offset)
 {
 	/* It is in the bitmap block number equal to the block
 	 * number divided by the number of bits in a block. */

@@ -58,7 +60,7 @@ static inline void get_bit_address(struc
 
 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
 {
-	int bmap, offset;
+	unsigned int bmap, offset;
 
 	if (block == 0 || block >= SB_BLOCK_COUNT(s)) {
 		reiserfs_warning(s,

@@ -108,8 +110,8 @@ int is_reusable(struct super_block *s, b
 
 /* searches in journal structures for a given block number (bmap, off). If block
    is found in reiserfs journal it suggests next free block candidate to test. */
-static inline int is_block_in_journal(struct super_block *s, int bmap, int
-				      off, int *next)
+static inline int is_block_in_journal(struct super_block *s, unsigned int bmap,
+                                      int off, int *next)
 {
 	b_blocknr_t tmp;
 

@@ -130,8 +132,8 @@ static inline int is_block_in_journal(st
 /* it searches for a window of zero bits with given minimum and maximum lengths in one bitmap
  * block; */
 static int scan_bitmap_block(struct reiserfs_transaction_handle *th,
-			     int bmap_n, int *beg, int boundary, int min,
-			     int max, int unfm)
+                             unsigned int bmap_n, int *beg, int boundary,
+                             int min, int max, int unfm)
 {
 	struct super_block *s = th->t_super;
 	struct reiserfs_bitmap_info *bi = &SB_AP_BITMAP(s)[bmap_n];

@@ -307,16 +309,16 @@ __le32 reiserfs_choose_packing(struct in
  * bitmap and place new blocks there. Returns number of allocated blocks. */
 static int scan_bitmap(struct reiserfs_transaction_handle *th,
 		       b_blocknr_t * start, b_blocknr_t finish,
-		       int min, int max, int unfm, unsigned long file_block)
+		       int min, int max, int unfm, sector_t file_block)
 {
 	int nr_allocated = 0;
 	struct super_block *s = th->t_super;
 	/* find every bm and bmap and bmap_nr in this file, and change them all to bitmap_blocknr
 	 * - Hans, it is not a block number - Zam. */
 
-	int bm, off;
-	int end_bm, end_off;
-	int off_max = s->s_blocksize << 3;
+	unsigned int bm, off;
+	unsigned int end_bm, end_off;
+	unsigned int off_max = s->s_blocksize << 3;
 
 	BUG_ON(!th->t_trans_id);
 

@@ -383,7 +385,7 @@ static void _reiserfs_free_block(struct 
 	struct reiserfs_super_block *rs;
 	struct buffer_head *sbh, *bmbh;
 	struct reiserfs_bitmap_info *apbi;
-	int nr, offset;
+	unsigned int nr, offset;
 
 	BUG_ON(!th->t_trans_id);
 

@@ -198,7 +198,7 @@ static inline void set_block_dev_mapped(
 // files which were created in the earlier version can not be longer,
 // than 2 gb
 //
-static int file_capable(struct inode *inode, long block)
+static int file_capable(struct inode *inode, sector_t block)
 {
 	if (get_inode_item_key_version(inode) != KEY_FORMAT_3_5 ||	// it is new file.
 	    block < (1 << (31 - inode->i_sb->s_blocksize_bits)))	// old file, but 'block' is inside of 2gb

@@ -241,7 +241,7 @@ static int file_capable(struct inode *in
 // Please improve the english/clarity in the comment above, as it is
 // hard to understand.
 
-static int _get_block_create_0(struct inode *inode, long block,
+static int _get_block_create_0(struct inode *inode, sector_t block,
 			       struct buffer_head *bh_result, int args)
 {
 	INITIALIZE_PATH(path);

@@ -249,7 +249,7 @@ static int _get_block_create_0(struct in
 	struct buffer_head *bh;
 	struct item_head *ih, tmp_ih;
 	int fs_gen;
-	int blocknr;
+	b_blocknr_t blocknr;
 	char *p = NULL;
 	int chars;
 	int ret;

@@ -568,7 +568,7 @@ static int convert_tail_for_hole(struct 
 }
 
 static inline int _allocate_block(struct reiserfs_transaction_handle *th,
-				  long block,
+				  sector_t block,
 				  struct inode *inode,
 				  b_blocknr_t * allocated_block_nr,
 				  struct treepath *path, int flags)

@@ -219,11 +219,12 @@ static void allocate_bitmap_nodes(struct
 	}
 }
 
-static int set_bit_in_list_bitmap(struct super_block *p_s_sb, int block,
+static int set_bit_in_list_bitmap(struct super_block *p_s_sb,
+                                  b_blocknr_t block,
 				  struct reiserfs_list_bitmap *jb)
 {
-	int bmap_nr = block / (p_s_sb->s_blocksize << 3);
-	int bit_nr = block % (p_s_sb->s_blocksize << 3);
+	unsigned int bmap_nr = block / (p_s_sb->s_blocksize << 3);
+	unsigned int bit_nr = block % (p_s_sb->s_blocksize << 3);
 
 	if (!jb->bitmaps[bmap_nr]) {
 		jb->bitmaps[bmap_nr] = get_bitmap_node(p_s_sb);

@@ -289,7 +290,7 @@ static int free_bitmap_nodes(struct supe
 */
 int reiserfs_allocate_list_bitmaps(struct super_block *p_s_sb,
 				   struct reiserfs_list_bitmap *jb_array,
-				   int bmap_nr)
+				   unsigned int bmap_nr)
 {
 	int i;
 	int failed = 0;

@@ -483,7 +484,7 @@ static inline struct reiserfs_journal_cn
 **
 */
 int reiserfs_in_journal(struct super_block *p_s_sb,
-			int bmap_nr, int bit_nr, int search_all,
+			unsigned int bmap_nr, int bit_nr, int search_all,
 			b_blocknr_t * next_zero_bit)
 {
 	struct reiserfs_journal *journal = SB_JOURNAL(p_s_sb);

@@ -986,7 +987,7 @@ static int flush_commit_list(struct supe
 			     struct reiserfs_journal_list *jl, int flushall)
 {
 	int i;
-	int bn;
+	b_blocknr_t bn;
 	struct buffer_head *tbh = NULL;
 	unsigned long trans_id = jl->j_trans_id;
 	struct reiserfs_journal *journal = SB_JOURNAL(s);

@@ -2279,8 +2280,9 @@ static int journal_read_transaction(stru
    Right now it is only used from journal code. But later we might use it
    from other places.
    Note: Do not use journal_getblk/sb_getblk functions here! */
-static struct buffer_head *reiserfs_breada(struct block_device *dev, int block,
-					   int bufsize, unsigned int max_block)
+static struct buffer_head *reiserfs_breada(struct block_device *dev,
+                                           b_blocknr_t block, int bufsize,
+                                           b_blocknr_t max_block)
 {
 	struct buffer_head *bhlist[BUFNR];
 	unsigned int blocks = BUFNR;

@@ -559,7 +559,7 @@ static int is_tree_node(struct buffer_he
 /* The function is NOT SCHEDULE-SAFE! */
 static void search_by_key_reada(struct super_block *s,
 				struct buffer_head **bh,
-				unsigned long *b, int num)
+				b_blocknr_t *b, int num)
 {
 	int i, j;
 

@@ -611,7 +611,7 @@ int search_by_key(struct super_block *p_
 					   DISK_LEAF_NODE_LEVEL */
     )
 {
-	int n_block_number;
+	b_blocknr_t n_block_number;
 	int expected_level;
 	struct buffer_head *p_s_bh;
 	struct path_element *p_s_last_element;

@@ -619,7 +619,7 @@ int search_by_key(struct super_block *p_
 	int right_neighbor_of_leaf_node;
 	int fs_gen;
 	struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
-	unsigned long reada_blocks[SEARCH_BY_KEY_READA];
+	b_blocknr_t reada_blocks[SEARCH_BY_KEY_READA];
 	int reada_count = 0;
 
 #ifdef CONFIG_REISERFS_CHECK

@@ -1736,8 +1736,8 @@ int journal_end_sync(struct reiserfs_tra
 int journal_mark_freed(struct reiserfs_transaction_handle *,
 		       struct super_block *, b_blocknr_t blocknr);
 int journal_transaction_should_end(struct reiserfs_transaction_handle *, int);
-int reiserfs_in_journal(struct super_block *p_s_sb, int bmap_nr, int bit_nr,
-			int searchall, b_blocknr_t * next);
+int reiserfs_in_journal(struct super_block *p_s_sb, unsigned int bmap_nr,
+                        int bit_nr, int searchall, b_blocknr_t * next);
 int journal_begin(struct reiserfs_transaction_handle *,
 		  struct super_block *p_s_sb, unsigned long);
 int journal_join_abort(struct reiserfs_transaction_handle *,

@@ -1745,7 +1745,7 @@ int journal_join_abort(struct reiserfs_t
 void reiserfs_journal_abort(struct super_block *sb, int errno);
 void reiserfs_abort(struct super_block *sb, int errno, const char *fmt, ...);
 int reiserfs_allocate_list_bitmaps(struct super_block *s,
-				   struct reiserfs_list_bitmap *, int);
+				   struct reiserfs_list_bitmap *, unsigned int);
 
 void add_save_link(struct reiserfs_transaction_handle *th,
 		   struct inode *inode, int truncate);

@@ -2045,7 +2045,7 @@ struct buffer_head *get_FEB(struct tree_
  * arguments, such as node, search path, transaction_handle, etc. */
 struct __reiserfs_blocknr_hint {
 	struct inode *inode;	/* inode passed to allocator, if we allocate unf. nodes */
-	long block;		/* file offset, in blocks */
+	sector_t block;		/* file offset, in blocks */
 	struct in_core_key key;
 	struct treepath *path;	/* search path, used by allocator to deternine search_start by
 				 * various ways */

@@ -2103,7 +2103,8 @@ static inline int reiserfs_new_form_bloc
 static inline int reiserfs_new_unf_blocknrs(struct reiserfs_transaction_handle
 					    *th, struct inode *inode,
 					    b_blocknr_t * new_blocknrs,
-					    struct treepath *path, long block)
+					    struct treepath *path,
+					    sector_t block)
 {
 	reiserfs_blocknr_hint_t hint = {
 		.th = th,

@@ -2120,7 +2121,8 @@ static inline int reiserfs_new_unf_block
 static inline int reiserfs_new_unf_blocknrs2(struct reiserfs_transaction_handle
 					     *th, struct inode *inode,
 					     b_blocknr_t * new_blocknrs,
-					     struct treepath *path, long block)
+					     struct treepath *path,
+					     sector_t block)
 {
 	reiserfs_blocknr_hint_t hint = {
 		.th = th,

@@ -119,7 +119,7 @@ int reiserfs_resize(struct super_block *
 			return -ENOMEM;
 		}
 		memset(bitmap, 0,
-		       sizeof(struct reiserfs_bitmap_info) * SB_BMAP_NR(s));
+		       sizeof(struct reiserfs_bitmap_info) * bmap_nr_new);
 		for (i = 0; i < bmap_nr; i++)
 			bitmap[i] = old_bitmap[i];
 

@@ -273,7 +273,7 @@ static inline int block_group_used(struc
 	 * to make a better decision. This favors long-term performace gain
 	 * with a better on-disk layout vs. a short term gain of skipping the
 	 * read and potentially having a bad placement. */
-	if (info->first_zero_hint == 0) {
+	if (info->free_count == UINT_MAX) {
 		struct buffer_head *bh = reiserfs_read_bitmap_block(s, bm);
 		brelse(bh);
 	}

@@ -1271,27 +1271,22 @@ void reiserfs_cache_bitmap_metadata(stru
 {
 	unsigned long *cur = (unsigned long *)(bh->b_data + bh->b_size);
 
-	info->first_zero_hint = 1 << (sb->s_blocksize_bits + 3);
+	/* The first bit must ALWAYS be 1 */
+	BUG_ON (!reiserfs_test_le_bit(0, (unsigned long)bh->b_data))
+
+	info->free_count = 0;
 
 	while (--cur >= (unsigned long *)bh->b_data) {
-		int base = ((char *)cur - bh->b_data) << 3;
+		int i;
 
 		/* 0 and ~0 are special, we can optimize for them */
-		if (*cur == 0) {
-			info->first_zero_hint = base;
+		if (*cur == 0)
 			info->free_count += BITS_PER_LONG;
-		} else if (*cur != ~0L) {       /* A mix, investigate */
-			int b;
-			for (b = BITS_PER_LONG - 1; b >= 0; b--) {
-				if (!reiserfs_test_le_bit(b, cur)) {
-					info->first_zero_hint = base + b;
+		else if (*cur != ~0L)	/* A mix, investigate */
+			for (i = BITS_PER_LONG - 1; i >= 0; i--)
+				if (!reiserfs_test_le_bit(i, cur))
 					info->free_count++;
-				}
-			}
-		}
 	}
-	/* The first bit must ALWAYS be 1 */
-	BUG_ON(info->first_zero_hint == 0);
 }
 
 struct buffer_head *reiserfs_read_bitmap_block(struct super_block *sb,

@@ -1321,7 +1316,7 @@ struct buffer_head *reiserfs_read_bitmap
 		BUG_ON(!buffer_uptodate(bh));
 		BUG_ON(atomic_read(&bh->b_count) == 0);
 
-		if (info->first_zero_hint == 0)
+		if (info->free_count == UINT_MAX)
 			reiserfs_cache_bitmap_metadata(sb, bh, info);
 	}
 

@@ -143,7 +143,6 @@ int reiserfs_resize(struct super_block *
 			mark_buffer_dirty(bh);
 			sync_dirty_buffer(bh);
 			// update bitmap_info stuff
-			bitmap[i].first_zero_hint = 1;
 			bitmap[i].free_count = sb_blocksize(sb) * 8 - 1;
 			brelse(bh);
 		}

@@ -173,8 +172,6 @@ int reiserfs_resize(struct super_block *
 	for (i = block_r; i < s->s_blocksize * 8; i++)
 		reiserfs_test_and_clear_le_bit(i, bh->b_data);
 	info->free_count += s->s_blocksize * 8 - block_r;
-	if (!info->first_zero_hint)
-		info->first_zero_hint = block_r;
 
 	journal_mark_dirty(&th, s, bh);
 	brelse(bh);

@@ -196,9 +193,6 @@ int reiserfs_resize(struct super_block *
 	brelse(bh);
 
 	info->free_count -= s->s_blocksize * 8 - block_r_new;
-	/* Extreme case where last bitmap is the only valid block in itself. */
-	if (!info->free_count)
-		info->first_zero_hint = 0;
 	/* update super */
 	reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
 	free_blocks = SB_FREE_BLOCKS(s);

@@ -265,9 +265,7 @@ enum journal_state_bits {
 typedef __u32(*hashf_t) (const signed char *, int);
 
 struct reiserfs_bitmap_info {
-	// FIXME: Won't work with block sizes > 8K
-	__u16 first_zero_hint;
-	__u16 free_count;
+	__u32 free_count;
 };
 
 struct proc_dir_entry;

@@ -61,6 +61,7 @@ static inline void get_bit_address(struc
 int is_reusable(struct super_block *s, b_blocknr_t block, int bit_value)
 {
 	unsigned int bmap, offset;
+	unsigned int bmap_count = reiserfs_bmap_count(s);
 
 	if (block == 0 || block >= SB_BLOCK_COUNT(s)) {
 		reiserfs_warning(s,

@@ -76,25 +77,26 @@ int is_reusable(struct super_block *s, b
 	if (unlikely(test_bit(REISERFS_OLD_FORMAT,
 			      &(REISERFS_SB(s)->s_properties)))) {
 		b_blocknr_t bmap1 = REISERFS_SB(s)->s_sbh->b_blocknr + 1;
-		if (block >= bmap1 && block <= bmap1 + SB_BMAP_NR(s)) {
+		if (block >= bmap1 &&
+		    block <= bmap1 + bmap_count) {
 			reiserfs_warning(s, "vs: 4019: is_reusable: "
 					 "bitmap block %lu(%u) can't be freed or reused",
-					 block, SB_BMAP_NR(s));
+					 block, bmap_count);
 			return 0;
 		}
 	} else {
 		if (offset == 0) {
 			reiserfs_warning(s, "vs: 4020: is_reusable: "
 					 "bitmap block %lu(%u) can't be freed or reused",
-					 block, SB_BMAP_NR(s));
+					 block, bmap_count);
 			return 0;
 		}
 	}
 
-	if (bmap >= SB_BMAP_NR(s)) {
+	if (bmap >= bmap_count) {
 		reiserfs_warning(s,
 				 "vs-4030: is_reusable: there is no so many bitmap blocks: "
-				 "block=%lu, bitmap_nr=%d", block, bmap);
+				 "block=%lu, bitmap_nr=%u", block, bmap);
 		return 0;
 	}
 

@@ -143,8 +145,8 @@ static int scan_bitmap_block(struct reis
 
 	BUG_ON(!th->t_trans_id);
 
-	RFALSE(bmap_n >= SB_BMAP_NR(s), "Bitmap %d is out of range (0..%d)",
-	       bmap_n, SB_BMAP_NR(s) - 1);
+	RFALSE(bmap_n >= reiserfs_bmap_count(s), "Bitmap %u is out of "
+	       "range (0..%u)", bmap_n, reiserfs_bmap_count(s) - 1);
 	PROC_INFO_INC(s, scan_bitmap.bmap);
 /* this is unclear and lacks comments, explain how journal bitmaps
    work here for the reader.  Convey a sense of the design here. What

@@ -249,12 +251,12 @@ static int bmap_hash_id(struct super_blo
 	} else {
 		hash_in = (char *)(&id);
 		hash = keyed_hash(hash_in, 4);
-		bm = hash % SB_BMAP_NR(s);
+		bm = hash % reiserfs_bmap_count(s);
 		if (!bm)
 			bm = 1;
 	}
 	/* this can only be true when SB_BMAP_NR = 1 */
-	if (bm >= SB_BMAP_NR(s))
+	if (bm >= reiserfs_bmap_count(s))
 		bm = 0;
 	return bm;
 }

@@ -328,10 +330,10 @@ static int scan_bitmap(struct reiserfs_t
 
 	get_bit_address(s, *start, &bm, &off);
 	get_bit_address(s, finish, &end_bm, &end_off);
-	if (bm > SB_BMAP_NR(s))
+	if (bm > reiserfs_bmap_count(s))
 		return 0;
-	if (end_bm > SB_BMAP_NR(s))
-		end_bm = SB_BMAP_NR(s);
+	if (end_bm > reiserfs_bmap_count(s))
+		end_bm = reiserfs_bmap_count(s);
 
 	/* When the bitmap is more than 10% free, anyone can allocate.
 	 * When it's less than 10% free, only files that already use the

@@ -397,10 +399,12 @@ static void _reiserfs_free_block(struct 
 
 	get_bit_address(s, block, &nr, &offset);
 
-	if (nr >= sb_bmap_nr(rs)) {
+	if (nr >= reiserfs_bmap_count(s)) {
 		reiserfs_warning(s, "vs-4075: reiserfs_free_block: "
-				 "block %lu is out of range on %s",
-				 block, reiserfs_bdevname(s));
+				 "block %lu is out of range on %s "
+				 "(nr=%u,max=%u)", block,
+				 reiserfs_bdevname(s), nr,
+				 reiserfs_bmap_count(s));
 		return;
 	}
 

@@ -1326,12 +1330,13 @@ struct buffer_head *reiserfs_read_bitmap
 int reiserfs_init_bitmap_cache(struct super_block *sb)
 {
 	struct reiserfs_bitmap_info *bitmap;
+	unsigned int bmap_nr = reiserfs_bmap_count(sb);
 
-	bitmap = vmalloc(sizeof (*bitmap) * SB_BMAP_NR(sb));
+	bitmap = vmalloc(sizeof (*bitmap) * bmap_nr);
 	if (bitmap == NULL)
 		return -ENOMEM;
 
-	memset(bitmap, 0, sizeof (*bitmap) * SB_BMAP_NR(sb));
+	memset(bitmap, 0, sizeof (*bitmap) * bmap_nr);
 
 	SB_AP_BITMAP(sb) = bitmap;
 

@@ -240,7 +240,7 @@ static void cleanup_bitmap_list(struct s
 	if (jb->bitmaps == NULL)
 		return;
 
-	for (i = 0; i < SB_BMAP_NR(p_s_sb); i++) {
+	for (i = 0; i < reiserfs_bmap_count(p_s_sb); i++) {
 		if (jb->bitmaps[i]) {
 			free_bitmap_node(p_s_sb, jb->bitmaps[i]);
 			jb->bitmaps[i] = NULL;

@@ -2651,7 +2651,7 @@ int journal_init(struct super_block *p_s
 	journal->j_persistent_trans = 0;
 	if (reiserfs_allocate_list_bitmaps(p_s_sb,
 					   journal->j_list_bitmap,
-					   SB_BMAP_NR(p_s_sb)))
+					   reiserfs_bmap_count(p_s_sb)))
 		goto free_and_return;
 	allocate_bitmap_nodes(p_s_sb);
 

@@ -2659,7 +2659,7 @@ int journal_init(struct super_block *p_s
 	SB_JOURNAL_1st_RESERVED_BLOCK(p_s_sb) = (old_format ?
 						 REISERFS_OLD_DISK_OFFSET_IN_BYTES
 						 / p_s_sb->s_blocksize +
-						 SB_BMAP_NR(p_s_sb) +
+						 reiserfs_bmap_count(p_s_sb) +
 						 1 :
 						 REISERFS_DISK_OFFSET_IN_BYTES /
 						 p_s_sb->s_blocksize + 2);

@@ -61,7 +61,7 @@ int reiserfs_resize(struct super_block *
 	}
 
 	/* count used bits in last bitmap block */
-	block_r = SB_BLOCK_COUNT(s) - (SB_BMAP_NR(s) - 1) * s->s_blocksize * 8;
+	block_r = SB_BLOCK_COUNT(s) - (reiserfs_bmap_count(s) - 1) * s->s_blocksize * 8;
 
 	/* count bitmap blocks in new fs */
 	bmap_nr_new = block_count_new / (s->s_blocksize * 8);

@@ -73,7 +73,7 @@ int reiserfs_resize(struct super_block *
 
 	/* save old values */
 	block_count = SB_BLOCK_COUNT(s);
-	bmap_nr = SB_BMAP_NR(s);
+	bmap_nr = reiserfs_bmap_count(s);
 
 	/* resizing of reiserfs bitmaps (journal and real), if needed */
 	if (bmap_nr_new > bmap_nr) {

@@ -200,7 +200,7 @@ int reiserfs_resize(struct super_block *
 			   free_blocks + (block_count_new - block_count -
 					  (bmap_nr_new - bmap_nr)));
 	PUT_SB_BLOCK_COUNT(s, block_count_new);
-	PUT_SB_BMAP_NR(s, bmap_nr_new);
+	PUT_SB_BMAP_NR(s, bmap_would_wrap(bmap_nr_new) ? : bmap_nr_new );
 	s->s_dirt = 1;
 
 	journal_mark_dirty(&th, s, SB_BUFFER_WITH_SB(s));

@@ -1713,6 +1713,21 @@ static int reiserfs_fill_super(struct su
 		set_sb_umount_state(rs, REISERFS_ERROR_FS);
 		set_sb_fs_state(rs, 0);
 
+		/* Clear out s_bmap_nr if it would wrap. We can handle this
+		 * case, but older revisions can't. This will cause the
+		 * file system to fail mount on those older implementations,
+		 * avoiding corruption. -jeffm */
+		if (bmap_would_wrap(reiserfs_bmap_count(s)) &&
+		    sb_bmap_nr(rs) != 0) {
+			reiserfs_warning(s, "super-2030: This file system "
+		                         "claims to use %u bitmap blocks in "
+		                         "its super block, but requires %u. "
+		                         "Clearing to zero.", sb_bmap_nr(rs),
+		                         reiserfs_bmap_count(s));
+
+			set_sb_bmap_nr(rs, 0);
+		}
+
 		if (old_format_only(s)) {
 			/* filesystem of format 3.5 either with standard or non-standard
 			   journal */

@@ -231,6 +231,11 @@ struct reiserfs_super_block {
          ((!is_reiserfs_jr(SB_DISK_SUPER_BLOCK(s)) ? \
          SB_ONDISK_JOURNAL_SIZE(s) + 1 : SB_ONDISK_RESERVED_FOR_JOURNAL(s)))
 
+/* s_bmap_nr is a u16 */
+#define reiserfs_bmap_count(sb)	reiserfs_bmap_nr(SB_BLOCK_COUNT(sb), sb->s_blocksize)
+#define reiserfs_bmap_nr(count, blk_size) ((count - 1) / (blk_size * 8) + 1)
+#define bmap_would_wrap(n)		(n > ((1LL << 16) - 1))
+
 int is_reiserfs_3_5(struct reiserfs_super_block *rs);
 int is_reiserfs_3_6(struct reiserfs_super_block *rs);
 int is_reiserfs_jr(struct reiserfs_super_block *rs);