Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/hfsplus

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/hfsplus:
  hfsplus: ensure bio requests are not smaller than the hardware sectors
  hfsplus: Add additional range check to handle on-disk corruptions
  hfsplus: Add error propagation for hfsplus_ext_write_extent_locked
  hfsplus: add error checking for hfs_find_init()
  hfsplus: lift the 2TB size limit
  hfsplus: fix overflow in hfsplus_read_wrapper
  hfsplus: fix overflow in hfsplus_get_block
  hfsplus: assignments inside `if' condition clean-up

fs/hfsplus/brec.c

@@ -43,6 +43,10 @@ u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
 			node->tree->node_size - (rec + 1) * 2);
 		if (!recoff)
 			return 0;
+		if (recoff > node->tree->node_size - 2) {
+			printk(KERN_ERR "hfs: recoff %d too large\n", recoff);
+			return 0;
+		}
 
 		retval = hfs_bnode_read_u16(node, recoff) + 2;
 		if (retval > node->tree->max_key_len + 2) {

fs/hfsplus/catalog.c

@@ -212,7 +212,9 @@ int hfsplus_create_cat(u32 cnid, struct inode *dir,
 
 	dprint(DBG_CAT_MOD, "create_cat: %s,%u(%d)\n",
 		str->name, cnid, inode->i_nlink);
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	if (err)
+		return err;
 
 	hfsplus_cat_build_key(sb, fd.search_key, cnid, NULL);
 	entry_size = hfsplus_fill_cat_thread(sb, &entry,
@@ -269,7 +271,9 @@ int hfsplus_delete_cat(u32 cnid, struct inode *dir, struct qstr *str)
 
 	dprint(DBG_CAT_MOD, "delete_cat: %s,%u\n",
 		str ? str->name : NULL, cnid);
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	if (err)
+		return err;
 
 	if (!str) {
 		int len;
@@ -347,12 +351,14 @@ int hfsplus_rename_cat(u32 cnid,
 	struct hfs_find_data src_fd, dst_fd;
 	hfsplus_cat_entry entry;
 	int entry_size, type;
-	int err = 0;
+	int err;
 
 	dprint(DBG_CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s\n",
 		cnid, src_dir->i_ino, src_name->name,
 		dst_dir->i_ino, dst_name->name);
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &src_fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &src_fd);
+	if (err)
+		return err;
 	dst_fd = src_fd;
 
 	/* find the old dir entry and read the data */

fs/hfsplus/dir.c

@@ -38,7 +38,9 @@ static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry,
 	sb = dir->i_sb;
 
 	dentry->d_fsdata = NULL;
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	if (err)
+		return ERR_PTR(err);
 	hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, &dentry->d_name);
 again:
 	err = hfs_brec_read(&fd, &entry, sizeof(entry));
@@ -132,7 +134,9 @@ static int hfsplus_readdir(struct file *filp, void *dirent, filldir_t filldir)
 	if (filp->f_pos >= inode->i_size)
 		return 0;
 
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	if (err)
+		return err;
 	hfsplus_cat_build_key(sb, fd.search_key, inode->i_ino, NULL);
 	err = hfs_brec_find(&fd);
 	if (err)

fs/hfsplus/extents.c

@@ -119,22 +119,31 @@ static void __hfsplus_ext_write_extent(struct inode *inode,
 	set_bit(HFSPLUS_I_EXT_DIRTY, &hip->flags);
 }
 
-static void hfsplus_ext_write_extent_locked(struct inode *inode)
+static int hfsplus_ext_write_extent_locked(struct inode *inode)
 {
+	int res;
+
 	if (HFSPLUS_I(inode)->extent_state & HFSPLUS_EXT_DIRTY) {
 		struct hfs_find_data fd;
 
-		hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
+		res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
+		if (res)
+			return res;
 		__hfsplus_ext_write_extent(inode, &fd);
 		hfs_find_exit(&fd);
 	}
+	return 0;
 }
 
-void hfsplus_ext_write_extent(struct inode *inode)
+int hfsplus_ext_write_extent(struct inode *inode)
 {
+	int res;
+
 	mutex_lock(&HFSPLUS_I(inode)->extents_lock);
-	hfsplus_ext_write_extent_locked(inode);
+	res = hfsplus_ext_write_extent_locked(inode);
 	mutex_unlock(&HFSPLUS_I(inode)->extents_lock);
+
+	return res;
 }
 
 static inline int __hfsplus_ext_read_extent(struct hfs_find_data *fd,
@@ -194,9 +203,11 @@ static int hfsplus_ext_read_extent(struct inode *inode, u32 block)
 	    block < hip->cached_start + hip->cached_blocks)
 		return 0;
 
-	hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
-	res = __hfsplus_ext_cache_extent(&fd, inode, block);
-	hfs_find_exit(&fd);
+	res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->ext_tree, &fd);
+	if (!res) {
+		res = __hfsplus_ext_cache_extent(&fd, inode, block);
+		hfs_find_exit(&fd);
+	}
 	return res;
 }
 
@@ -209,6 +220,7 @@ int hfsplus_get_block(struct inode *inode, sector_t iblock,
 	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
 	int res = -EIO;
 	u32 ablock, dblock, mask;
+	sector_t sector;
 	int was_dirty = 0;
 	int shift;
 
@@ -255,10 +267,12 @@ int hfsplus_get_block(struct inode *inode, sector_t iblock,
 done:
 	dprint(DBG_EXTENT, "get_block(%lu): %llu - %u\n",
 		inode->i_ino, (long long)iblock, dblock);
+
 	mask = (1 << sbi->fs_shift) - 1;
-	map_bh(bh_result, sb,
-		(dblock << sbi->fs_shift) + sbi->blockoffset +
-			(iblock & mask));
+	sector = ((sector_t)dblock << sbi->fs_shift) +
+		  sbi->blockoffset + (iblock & mask);
+	map_bh(bh_result, sb, sector);
+
 	if (create) {
 		set_buffer_new(bh_result);
 		hip->phys_size += sb->s_blocksize;
@@ -371,7 +385,9 @@ int hfsplus_free_fork(struct super_block *sb, u32 cnid,
 	if (total_blocks == blocks)
 		return 0;
 
-	hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	if (res)
+		return res;
 	do {
 		res = __hfsplus_ext_read_extent(&fd, ext_entry, cnid,
 						total_blocks, type);
@@ -469,7 +485,9 @@ out:
 
 insert_extent:
 	dprint(DBG_EXTENT, "insert new extent\n");
-	hfsplus_ext_write_extent_locked(inode);
+	res = hfsplus_ext_write_extent_locked(inode);
+	if (res)
+		goto out;
 
 	memset(hip->cached_extents, 0, sizeof(hfsplus_extent_rec));
 	hip->cached_extents[0].start_block = cpu_to_be32(start);
@@ -500,7 +518,6 @@ void hfsplus_file_truncate(struct inode *inode)
 		struct page *page;
 		void *fsdata;
 		u32 size = inode->i_size;
-		int res;
 
 		res = pagecache_write_begin(NULL, mapping, size, 0,
 						AOP_FLAG_UNINTERRUPTIBLE,
@@ -523,7 +540,12 @@ void hfsplus_file_truncate(struct inode *inode)
 		goto out;
 
 	mutex_lock(&hip->extents_lock);
-	hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	res = hfs_find_init(HFSPLUS_SB(sb)->ext_tree, &fd);
+	if (res) {
+		mutex_unlock(&hip->extents_lock);
+		/* XXX: We lack error handling of hfsplus_file_truncate() */
+		return;
+	}
 	while (1) {
 		if (alloc_cnt == hip->first_blocks) {
 			hfsplus_free_extents(sb, hip->first_extents,

fs/hfsplus/hfsplus_fs.h

@@ -13,6 +13,7 @@
 #include <linux/fs.h>
 #include <linux/mutex.h>
 #include <linux/buffer_head.h>
+#include <linux/blkdev.h>
 #include "hfsplus_raw.h"
 
 #define DBG_BNODE_REFS	0x00000001
@@ -110,7 +111,9 @@ struct hfsplus_vh;
 struct hfs_btree;
 
 struct hfsplus_sb_info {
+	void *s_vhdr_buf;
 	struct hfsplus_vh *s_vhdr;
+	void *s_backup_vhdr_buf;
 	struct hfsplus_vh *s_backup_vhdr;
 	struct hfs_btree *ext_tree;
 	struct hfs_btree *cat_tree;
@@ -258,6 +261,15 @@ struct hfsplus_readdir_data {
 	struct hfsplus_cat_key key;
 };
 
+/*
+ * Find minimum acceptible I/O size for an hfsplus sb.
+ */
+static inline unsigned short hfsplus_min_io_size(struct super_block *sb)
+{
+	return max_t(unsigned short, bdev_logical_block_size(sb->s_bdev),
+		     HFSPLUS_SECTOR_SIZE);
+}
+
 #define hfs_btree_open hfsplus_btree_open
 #define hfs_btree_close hfsplus_btree_close
 #define hfs_btree_write hfsplus_btree_write
@@ -374,7 +386,7 @@ extern const struct file_operations hfsplus_dir_operations;
 
 /* extents.c */
 int hfsplus_ext_cmp_key(const hfsplus_btree_key *, const hfsplus_btree_key *);
-void hfsplus_ext_write_extent(struct inode *);
+int hfsplus_ext_write_extent(struct inode *);
 int hfsplus_get_block(struct inode *, sector_t, struct buffer_head *, int);
 int hfsplus_free_fork(struct super_block *, u32,
 		struct hfsplus_fork_raw *, int);
@@ -436,8 +448,8 @@ int hfsplus_compare_dentry(const struct dentry *parent,
 /* wrapper.c */
 int hfsplus_read_wrapper(struct super_block *);
 int hfs_part_find(struct super_block *, sector_t *, sector_t *);
-int hfsplus_submit_bio(struct block_device *bdev, sector_t sector,
-		void *data, int rw);
+int hfsplus_submit_bio(struct super_block *sb, sector_t sector,
+		void *buf, void **data, int rw);
 
 /* time macros */
 #define __hfsp_mt2ut(t)		(be32_to_cpu(t) - 2082844800U)

fs/hfsplus/inode.c

@@ -195,11 +195,13 @@ static struct dentry *hfsplus_file_lookup(struct inode *dir,
 	hip->flags = 0;
 	set_bit(HFSPLUS_I_RSRC, &hip->flags);
 
-	hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
-	err = hfsplus_find_cat(sb, dir->i_ino, &fd);
-	if (!err)
-		err = hfsplus_cat_read_inode(inode, &fd);
-	hfs_find_exit(&fd);
+	err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
+	if (!err) {
+		err = hfsplus_find_cat(sb, dir->i_ino, &fd);
+		if (!err)
+			err = hfsplus_cat_read_inode(inode, &fd);
+		hfs_find_exit(&fd);
+	}
 	if (err) {
 		iput(inode);
 		return ERR_PTR(err);

fs/hfsplus/part_tbl.c

@@ -88,11 +88,12 @@ static int hfs_parse_old_pmap(struct super_block *sb, struct old_pmap *pm,
 	return -ENOENT;
 }
 
-static int hfs_parse_new_pmap(struct super_block *sb, struct new_pmap *pm,
-		sector_t *part_start, sector_t *part_size)
+static int hfs_parse_new_pmap(struct super_block *sb, void *buf,
+		struct new_pmap *pm, sector_t *part_start, sector_t *part_size)
 {
 	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 	int size = be32_to_cpu(pm->pmMapBlkCnt);
+	int buf_size = hfsplus_min_io_size(sb);
 	int res;
 	int i = 0;
 
@@ -107,11 +108,14 @@ static int hfs_parse_new_pmap(struct super_block *sb, struct new_pmap *pm,
 		if (++i >= size)
 			return -ENOENT;
 
-		res = hfsplus_submit_bio(sb->s_bdev,
-					 *part_start + HFS_PMAP_BLK + i,
-					 pm, READ);
-		if (res)
-			return res;
+		pm = (struct new_pmap *)((u8 *)pm + HFSPLUS_SECTOR_SIZE);
+		if ((u8 *)pm - (u8 *)buf >= buf_size) {
+			res = hfsplus_submit_bio(sb,
+						 *part_start + HFS_PMAP_BLK + i,
+						 buf, (void **)&pm, READ);
+			if (res)
+				return res;
+		}
 	} while (pm->pmSig == cpu_to_be16(HFS_NEW_PMAP_MAGIC));
 
 	return -ENOENT;
@@ -124,15 +128,15 @@ static int hfs_parse_new_pmap(struct super_block *sb, struct new_pmap *pm,
 int hfs_part_find(struct super_block *sb,
 		sector_t *part_start, sector_t *part_size)
 {
-	void *data;
+	void *buf, *data;
 	int res;
 
-	data = kmalloc(HFSPLUS_SECTOR_SIZE, GFP_KERNEL);
-	if (!data)
+	buf = kmalloc(hfsplus_min_io_size(sb), GFP_KERNEL);
+	if (!buf)
 		return -ENOMEM;
 
-	res = hfsplus_submit_bio(sb->s_bdev, *part_start + HFS_PMAP_BLK,
-				 data, READ);
+	res = hfsplus_submit_bio(sb, *part_start + HFS_PMAP_BLK,
+				 buf, &data, READ);
 	if (res)
 		goto out;
 
@@ -141,13 +145,13 @@ int hfs_part_find(struct super_block *sb,
 		res = hfs_parse_old_pmap(sb, data, part_start, part_size);
 		break;
 	case HFS_NEW_PMAP_MAGIC:
-		res = hfs_parse_new_pmap(sb, data, part_start, part_size);
+		res = hfs_parse_new_pmap(sb, buf, data, part_start, part_size);
 		break;
 	default:
 		res = -ENOENT;
 		break;
 	}
 out:
-	kfree(data);
+	kfree(buf);
 	return res;
 }

fs/hfsplus/super.c

@@ -73,11 +73,13 @@ struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino)
 
 	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
 	    inode->i_ino == HFSPLUS_ROOT_CNID) {
-		hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
-		err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
-		if (!err)
-			err = hfsplus_cat_read_inode(inode, &fd);
-		hfs_find_exit(&fd);
+		err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
+		if (!err) {
+			err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
+			if (!err)
+				err = hfsplus_cat_read_inode(inode, &fd);
+			hfs_find_exit(&fd);
+		}
 	} else {
 		err = hfsplus_system_read_inode(inode);
 	}
@@ -133,9 +135,13 @@ static int hfsplus_system_write_inode(struct inode *inode)
 static int hfsplus_write_inode(struct inode *inode,
 		struct writeback_control *wbc)
 {
+	int err;
+
 	dprint(DBG_INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
 
-	hfsplus_ext_write_extent(inode);
+	err = hfsplus_ext_write_extent(inode);
+	if (err)
+		return err;
 
 	if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
 	    inode->i_ino == HFSPLUS_ROOT_CNID)
@@ -197,17 +203,17 @@ int hfsplus_sync_fs(struct super_block *sb, int wait)
 		write_backup = 1;
 	}
 
-	error2 = hfsplus_submit_bio(sb->s_bdev,
+	error2 = hfsplus_submit_bio(sb,
 				   sbi->part_start + HFSPLUS_VOLHEAD_SECTOR,
-				   sbi->s_vhdr, WRITE_SYNC);
+				   sbi->s_vhdr_buf, NULL, WRITE_SYNC);
 	if (!error)
 		error = error2;
 	if (!write_backup)
 		goto out;
 
-	error2 = hfsplus_submit_bio(sb->s_bdev,
+	error2 = hfsplus_submit_bio(sb,
 				  sbi->part_start + sbi->sect_count - 2,
-				  sbi->s_backup_vhdr, WRITE_SYNC);
+				  sbi->s_backup_vhdr_buf, NULL, WRITE_SYNC);
 	if (!error)
 		error2 = error;
 out:
@@ -251,8 +257,8 @@ static void hfsplus_put_super(struct super_block *sb)
 	hfs_btree_close(sbi->ext_tree);
 	iput(sbi->alloc_file);
 	iput(sbi->hidden_dir);
-	kfree(sbi->s_vhdr);
-	kfree(sbi->s_backup_vhdr);
+	kfree(sbi->s_vhdr_buf);
+	kfree(sbi->s_backup_vhdr_buf);
 	unload_nls(sbi->nls);
 	kfree(sb->s_fs_info);
 	sb->s_fs_info = NULL;
@@ -393,6 +399,13 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 	if (!sbi->rsrc_clump_blocks)
 		sbi->rsrc_clump_blocks = 1;
 
+	err = generic_check_addressable(sbi->alloc_blksz_shift,
+					sbi->total_blocks);
+	if (err) {
+		printk(KERN_ERR "hfs: filesystem size too large.\n");
+		goto out_free_vhdr;
+	}
+
 	/* Set up operations so we can load metadata */
 	sb->s_op = &hfsplus_sops;
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
@@ -417,6 +430,8 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 		sb->s_flags |= MS_RDONLY;
 	}
 
+	err = -EINVAL;
+
 	/* Load metadata objects (B*Trees) */
 	sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
 	if (!sbi->ext_tree) {
@@ -447,7 +462,9 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 
 	str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
 	str.name = HFSP_HIDDENDIR_NAME;
-	hfs_find_init(sbi->cat_tree, &fd);
+	err = hfs_find_init(sbi->cat_tree, &fd);
+	if (err)
+		goto out_put_root;
 	hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
 	if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
 		hfs_find_exit(&fd);

fs/hfsplus/unicode.c

@@ -142,7 +142,11 @@ int hfsplus_uni2asc(struct super_block *sb,
 		/* search for single decomposed char */
 		if (likely(compose))
 			ce1 = hfsplus_compose_lookup(hfsplus_compose_table, c0);
-		if (ce1 && (cc = ce1[0])) {
+		if (ce1)
+			cc = ce1[0];
+		else
+			cc = 0;
+		if (cc) {
 			/* start of a possibly decomposed Hangul char */
 			if (cc != 0xffff)
 				goto done;
@@ -209,7 +213,8 @@ int hfsplus_uni2asc(struct super_block *sb,
 				i++;
 				ce2 = ce1;
 			}
-			if ((cc = ce2[0])) {
+			cc = ce2[0];
+			if (cc) {
 				ip += i;
 				ustrlen -= i;
 				goto done;
@@ -301,7 +306,11 @@ int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
 	while (outlen < HFSPLUS_MAX_STRLEN && len > 0) {
 		size = asc2unichar(sb, astr, len, &c);
 
-		if (decompose && (dstr = decompose_unichar(c, &dsize))) {
+		if (decompose)
+			dstr = decompose_unichar(c, &dsize);
+		else
+			dstr = NULL;
+		if (dstr) {
 			if (outlen + dsize > HFSPLUS_MAX_STRLEN)
 				break;
 			do {
@@ -346,15 +355,23 @@ int hfsplus_hash_dentry(const struct dentry *dentry, const struct inode *inode,
 		astr += size;
 		len -= size;
 
-		if (decompose && (dstr = decompose_unichar(c, &dsize))) {
+		if (decompose)
+			dstr = decompose_unichar(c, &dsize);
+		else
+			dstr = NULL;
+		if (dstr) {
 			do {
 				c2 = *dstr++;
-				if (!casefold || (c2 = case_fold(c2)))
+				if (casefold)
+					c2 = case_fold(c2);
+				if (!casefold || c2)
 					hash = partial_name_hash(c2, hash);
 			} while (--dsize > 0);
 		} else {
 			c2 = c;
-			if (!casefold || (c2 = case_fold(c2)))
+			if (casefold)
+				c2 = case_fold(c2);
+			if (!casefold || c2)
 				hash = partial_name_hash(c2, hash);
 		}
 	}
@@ -422,12 +439,14 @@ int hfsplus_compare_dentry(const struct dentry *parent,
 		c1 = *dstr1;
 		c2 = *dstr2;
 		if (casefold) {
-			if  (!(c1 = case_fold(c1))) {
+			c1 = case_fold(c1);
+			if (!c1) {
 				dstr1++;
 				dsize1--;
 				continue;
 			}
-			if (!(c2 = case_fold(c2))) {
+			c2 = case_fold(c2);
+			if (!c2) {
 				dstr2++;
 				dsize2--;
 				continue;

fs/hfsplus/wrapper.c

@@ -31,25 +31,67 @@ static void hfsplus_end_io_sync(struct bio *bio, int err)
 	complete(bio->bi_private);
 }
 
-int hfsplus_submit_bio(struct block_device *bdev, sector_t sector,
-		void *data, int rw)
+/*
+ * hfsplus_submit_bio - Perfrom block I/O
+ * @sb: super block of volume for I/O
+ * @sector: block to read or write, for blocks of HFSPLUS_SECTOR_SIZE bytes
+ * @buf: buffer for I/O
+ * @data: output pointer for location of requested data
+ * @rw: direction of I/O
+ *
+ * The unit of I/O is hfsplus_min_io_size(sb), which may be bigger than
+ * HFSPLUS_SECTOR_SIZE, and @buf must be sized accordingly. On reads
+ * @data will return a pointer to the start of the requested sector,
+ * which may not be the same location as @buf.
+ *
+ * If @sector is not aligned to the bdev logical block size it will
+ * be rounded down. For writes this means that @buf should contain data
+ * that starts at the rounded-down address. As long as the data was
+ * read using hfsplus_submit_bio() and the same buffer is used things
+ * will work correctly.
+ */
+int hfsplus_submit_bio(struct super_block *sb, sector_t sector,
+		void *buf, void **data, int rw)
 {
 	DECLARE_COMPLETION_ONSTACK(wait);
 	struct bio *bio;
 	int ret = 0;
+	unsigned int io_size;
+	loff_t start;
+	int offset;
+
+	/*
+	 * Align sector to hardware sector size and find offset. We
+	 * assume that io_size is a power of two, which _should_
+	 * be true.
+	 */
+	io_size = hfsplus_min_io_size(sb);
+	start = (loff_t)sector << HFSPLUS_SECTOR_SHIFT;
+	offset = start & (io_size - 1);
+	sector &= ~((io_size >> HFSPLUS_SECTOR_SHIFT) - 1);
 
 	bio = bio_alloc(GFP_NOIO, 1);
 	bio->bi_sector = sector;
-	bio->bi_bdev = bdev;
+	bio->bi_bdev = sb->s_bdev;
 	bio->bi_end_io = hfsplus_end_io_sync;
 	bio->bi_private = &wait;
 
-	/*
-	 * We always submit one sector at a time, so bio_add_page must not fail.
-	 */
-	if (bio_add_page(bio, virt_to_page(data), HFSPLUS_SECTOR_SIZE,
-			 offset_in_page(data)) != HFSPLUS_SECTOR_SIZE)
-		BUG();
+	if (!(rw & WRITE) && data)
+		*data = (u8 *)buf + offset;
+
+	while (io_size > 0) {
+		unsigned int page_offset = offset_in_page(buf);
+		unsigned int len = min_t(unsigned int, PAGE_SIZE - page_offset,
+					 io_size);
+
+		ret = bio_add_page(bio, virt_to_page(buf), len, page_offset);
+		if (ret != len) {
+			ret = -EIO;
+			goto out;
+		}
+		io_size -= len;
+		buf = (u8 *)buf + len;
+	}
 
 	submit_bio(rw, bio);
 	wait_for_completion(&wait);
@@ -57,8 +99,9 @@ int hfsplus_submit_bio(struct block_device *bdev, sector_t sector,
 	if (!bio_flagged(bio, BIO_UPTODATE))
 		ret = -EIO;
 
+out:
 	bio_put(bio);
-	return ret;
+	return ret < 0 ? ret : 0;
 }
 
 static int hfsplus_read_mdb(void *bufptr, struct hfsplus_wd *wd)
@@ -141,23 +184,19 @@ int hfsplus_read_wrapper(struct super_block *sb)
 
 	if (hfsplus_get_last_session(sb, &part_start, &part_size))
 		goto out;
-	if ((u64)part_start + part_size > 0x100000000ULL) {
-		pr_err("hfs: volumes larger than 2TB are not supported yet\n");
-		goto out;
-	}
 
 	error = -ENOMEM;
-	sbi->s_vhdr = kmalloc(HFSPLUS_SECTOR_SIZE, GFP_KERNEL);
-	if (!sbi->s_vhdr)
+	sbi->s_vhdr_buf = kmalloc(hfsplus_min_io_size(sb), GFP_KERNEL);
+	if (!sbi->s_vhdr_buf)
 		goto out;
-	sbi->s_backup_vhdr = kmalloc(HFSPLUS_SECTOR_SIZE, GFP_KERNEL);
-	if (!sbi->s_backup_vhdr)
+	sbi->s_backup_vhdr_buf = kmalloc(hfsplus_min_io_size(sb), GFP_KERNEL);
+	if (!sbi->s_backup_vhdr_buf)
 		goto out_free_vhdr;
 
 reread:
-	error = hfsplus_submit_bio(sb->s_bdev,
-				   part_start + HFSPLUS_VOLHEAD_SECTOR,
-				   sbi->s_vhdr, READ);
+	error = hfsplus_submit_bio(sb, part_start + HFSPLUS_VOLHEAD_SECTOR,
+				   sbi->s_vhdr_buf, (void **)&sbi->s_vhdr,
+				   READ);
 	if (error)
 		goto out_free_backup_vhdr;
 
@@ -172,8 +211,9 @@ reread:
 		if (!hfsplus_read_mdb(sbi->s_vhdr, &wd))
 			goto out_free_backup_vhdr;
 		wd.ablk_size >>= HFSPLUS_SECTOR_SHIFT;
-		part_start += wd.ablk_start + wd.embed_start * wd.ablk_size;
-		part_size = wd.embed_count * wd.ablk_size;
+		part_start += (sector_t)wd.ablk_start +
+			       (sector_t)wd.embed_start * wd.ablk_size;
+		part_size = (sector_t)wd.embed_count * wd.ablk_size;
 		goto reread;
 	default:
 		/*
@@ -186,9 +226,9 @@ reread:
 		goto reread;
 	}
 
-	error = hfsplus_submit_bio(sb->s_bdev,
-				   part_start + part_size - 2,
-				   sbi->s_backup_vhdr, READ);
+	error = hfsplus_submit_bio(sb, part_start + part_size - 2,
+				   sbi->s_backup_vhdr_buf,
+				   (void **)&sbi->s_backup_vhdr, READ);
 	if (error)
 		goto out_free_backup_vhdr;