udf: Fix 64-bit sign extension issues affecting blocks > 0x7FFFFFFF

Large (> 1 TiB) UDF filesystems appear subject to several problems when
mounted on 64-bit systems:

* readdir() can fail on a directory containing File Identifiers residing
  above 0x7FFFFFFF. This manifests as a 'ls' command failing with EIO.

* FIBMAP on a file block located above 0x7FFFFFFF can return a negative
  value. The low 32 bits are correct, but applications that don't mask the
  high 32 bits of the result can perform incorrectly.

Per suggestion by Jan Kara, introduce a udf_pblk_t type for representation
of UDF block addresses. Ultimately, all driver functions that manipulate
UDF block addresses should use this type; for now, deployment is limited
to functions with actual or potential sign extension issues.

Changes to udf_readdir() and udf_block_map() address the issues noted
above; other changes address potential similar issues uncovered during
audit of the driver code.

Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 63b0349..8e51704 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -73,6 +73,8 @@ static inline size_t udf_ext0_offset(struct inode *inode)
 /* computes tag checksum */
 u8 udf_tag_checksum(const struct tag *t);
 
+typedef uint32_t udf_pblk_t;
+
 struct dentry;
 struct inode;
 struct task_struct;
@@ -144,15 +146,17 @@ static inline struct inode *udf_iget(struct super_block *sb,
 	return __udf_iget(sb, ino, false);
 }
 extern int udf_expand_file_adinicb(struct inode *);
-extern struct buffer_head *udf_expand_dir_adinicb(struct inode *, int *, int *);
-extern struct buffer_head *udf_bread(struct inode *, int, int, int *);
+extern struct buffer_head *udf_expand_dir_adinicb(struct inode *inode,
+						  udf_pblk_t *block, int *err);
+extern struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
+				      int create, int *err);
 extern int udf_setsize(struct inode *, loff_t);
 extern void udf_evict_inode(struct inode *);
 extern int udf_write_inode(struct inode *, struct writeback_control *wbc);
-extern long udf_block_map(struct inode *, sector_t);
+extern udf_pblk_t udf_block_map(struct inode *inode, sector_t block);
 extern int8_t inode_bmap(struct inode *, sector_t, struct extent_position *,
 			 struct kernel_lb_addr *, uint32_t *, sector_t *);
-extern int udf_setup_indirect_aext(struct inode *inode, int block,
+extern int udf_setup_indirect_aext(struct inode *inode, udf_pblk_t block,
 				   struct extent_position *epos);
 extern int __udf_add_aext(struct inode *inode, struct extent_position *epos,
 			  struct kernel_lb_addr *eloc, uint32_t elen, int inc);
@@ -168,8 +172,9 @@ extern int8_t udf_current_aext(struct inode *, struct extent_position *,
 			       struct kernel_lb_addr *, uint32_t *, int);
 
 /* misc.c */
-extern struct buffer_head *udf_tgetblk(struct super_block *, int);
-extern struct buffer_head *udf_tread(struct super_block *, int);
+extern struct buffer_head *udf_tgetblk(struct super_block *sb,
+					udf_pblk_t block);
+extern struct buffer_head *udf_tread(struct super_block *sb, udf_pblk_t block);
 extern struct genericFormat *udf_add_extendedattr(struct inode *, uint32_t,
 						  uint32_t, uint8_t);
 extern struct genericFormat *udf_get_extendedattr(struct inode *, uint32_t,
@@ -228,8 +233,8 @@ extern void udf_free_blocks(struct super_block *, struct inode *,
 			    struct kernel_lb_addr *, uint32_t, uint32_t);
 extern int udf_prealloc_blocks(struct super_block *, struct inode *, uint16_t,
 			       uint32_t, uint32_t);
-extern int udf_new_block(struct super_block *, struct inode *, uint16_t,
-			 uint32_t, int *);
+extern udf_pblk_t udf_new_block(struct super_block *sb, struct inode *inode,
+				 uint16_t partition, uint32_t goal, int *err);
 
 /* directory.c */
 extern struct fileIdentDesc *udf_fileident_read(struct inode *, loff_t *,