ext4: Convert BUG_ON checks to use ext4_error() instead

Convert a bunch of BUG_ONs to emit a ext4_error() message and return
EIO.  This is a first pass and most notably does _not_ cover
mballoc.c, which is a morass of void functions.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/ext4.h

@@ -53,6 +53,12 @@
 #define ext4_debug(f, a...)	do {} while (0)
 #endif
 
+#define EXT4_ERROR_INODE(inode, fmt, a...) \
+	ext4_error_inode(__func__, (inode), (fmt), ## a);
+
+#define EXT4_ERROR_FILE(file, fmt, a...)	\
+	ext4_error_file(__func__, (file), (fmt), ## a);
+
 /* data type for block offset of block group */
 typedef int ext4_grpblk_t;
 
@@ -1492,6 +1498,10 @@ extern int ext4_group_extend(struct super_block *sb,
 extern void __ext4_error(struct super_block *, const char *, const char *, ...)
 	__attribute__ ((format (printf, 3, 4)));
 #define ext4_error(sb, message...)	__ext4_error(sb, __func__, ## message)
+extern void ext4_error_inode(const char *, struct inode *, const char *, ...)
+	__attribute__ ((format (printf, 3, 4)));
+extern void ext4_error_file(const char *, struct file *, const char *, ...)
+	__attribute__ ((format (printf, 3, 4)));
 extern void __ext4_std_error(struct super_block *, const char *, int);
 extern void ext4_abort(struct super_block *, const char *, const char *, ...)
 	__attribute__ ((format (printf, 3, 4)));

fs/ext4/inode.c

@@ -607,7 +607,14 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
 		if (*err)
 			goto failed_out;
 
-		BUG_ON(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS);
+		if (unlikely(current_block + count > EXT4_MAX_BLOCK_FILE_PHYS)) {
+			EXT4_ERROR_INODE(inode,
+					 "current_block %llu + count %lu > %d!",
+					 current_block, count,
+					 EXT4_MAX_BLOCK_FILE_PHYS);
+			*err = -EIO;
+			goto failed_out;
+		}
 
 		target -= count;
 		/* allocate blocks for indirect blocks */
@@ -643,7 +650,14 @@ static int ext4_alloc_blocks(handle_t *handle, struct inode *inode,
 		ar.flags = EXT4_MB_HINT_DATA;
 
 	current_block = ext4_mb_new_blocks(handle, &ar, err);
-	BUG_ON(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS);
+	if (unlikely(current_block + ar.len > EXT4_MAX_BLOCK_FILE_PHYS)) {
+		EXT4_ERROR_INODE(inode,
+				 "current_block %llu + ar.len %d > %d!",
+				 current_block, ar.len,
+				 EXT4_MAX_BLOCK_FILE_PHYS);
+		*err = -EIO;
+		goto failed_out;
+	}
 
 	if (*err && (target == blks)) {
 		/*

fs/ext4/super.c

@@ -347,6 +347,42 @@ void __ext4_error(struct super_block *sb, const char *function,
 	ext4_handle_error(sb);
 }
 
+void ext4_error_inode(const char *function, struct inode *inode,
+		      const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	printk(KERN_CRIT "EXT4-fs error (device %s): %s: inode #%lu: (comm %s) ",
+	       inode->i_sb->s_id, function, inode->i_ino, current->comm);
+	vprintk(fmt, args);
+	printk("\n");
+	va_end(args);
+
+	ext4_handle_error(inode->i_sb);
+}
+
+void ext4_error_file(const char *function, struct file *file,
+		     const char *fmt, ...)
+{
+	va_list args;
+	struct inode *inode = file->f_dentry->d_inode;
+	char pathname[80], *path;
+
+	va_start(args, fmt);
+	path = d_path(&(file->f_path), pathname, sizeof(pathname));
+	if (!path)
+		path = "(unknown)";
+	printk(KERN_CRIT
+	       "EXT4-fs error (device %s): %s: inode #%lu (comm %s path %s): ",
+	       inode->i_sb->s_id, function, inode->i_ino, current->comm, path);
+	vprintk(fmt, args);
+	printk("\n");
+	va_end(args);
+
+	ext4_handle_error(inode->i_sb);
+}
+
 static const char *ext4_decode_error(struct super_block *sb, int errno,
 				     char nbuf[16])
 {