Merge branch 'for-next/ext4'

2 files changed, 23 insertions, 70 deletions

diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index 55e837b4bd..c9f27f1278 100644
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -52,7 +52,7 @@ static struct ext4_extent_header *ext4fs_get_extent_block(struct ext2_data *data
 		index = (struct ext4_extent_idx *)(ext_block + 1);
 
 		if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
-			return 0;
+			return NULL;
 
 		if (ext_block->eh_depth == 0)
 			return ext_block;
@@ -64,7 +64,7 @@ static struct ext4_extent_header *ext4fs_get_extent_block(struct ext2_data *data
 		} while (fileblock >= le32_to_cpu(index[i].ei_block));
 
 		if (--i < 0)
-			return 0;
+			return NULL;
 
 		block = le16_to_cpu(index[i].ei_leaf_hi);
 		block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
@@ -167,10 +167,11 @@ long int read_allocated_block(struct ext2fs_node *node, int fileblock)
 	log2_blksz = LOG2_EXT2_BLOCK_SIZE(node->data);
 
 	if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
+		long int startblock, endblock;
 		char *buf = zalloc(blksz);
 		struct ext4_extent_header *ext_block;
 		struct ext4_extent *extent;
-		int i = -1;
+		int i;
 
 		if (!buf)
 			return -ENOMEM;
@@ -186,28 +187,27 @@ long int read_allocated_block(struct ext2fs_node *node, int fileblock)
 
 		extent = (struct ext4_extent *)(ext_block + 1);
 
-		do {
-			i++;
-			if (i >= le16_to_cpu(ext_block->eh_entries))
-				break;
-		} while (fileblock >= le32_to_cpu(extent[i].ee_block));
+		for (i = 0; i < le16_to_cpu(ext_block->eh_entries); i++) {
+			startblock = le32_to_cpu(extent[i].ee_block);
+			endblock = startblock + le16_to_cpu(extent[i].ee_len);
 
-		if (--i >= 0) {
-			fileblock -= le32_to_cpu(extent[i].ee_block);
-			if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
+			if (startblock > fileblock) {
+				/* Sparse file */
 				free(buf);
 				return 0;
 			}
 
-			start = le16_to_cpu(extent[i].ee_start_hi);
-			start = (start << 32) +
+			if (fileblock < endblock) {
+				start = le16_to_cpu(extent[i].ee_start_hi);
+				start = (start << 32) +
 					le32_to_cpu(extent[i].ee_start_lo);
-			free(buf);
-			return fileblock + start;
+				free(buf);
+				return (fileblock - startblock) + start;
+			}
 		}
 
 		free(buf);
-		return -EIO;
+		return 0;
 	}
 
 	if (fileblock < INDIRECT_BLOCKS) {
diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index bfc5f27cc3..2d231d273a 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -55,12 +55,6 @@ int ext4fs_read_file(struct ext2fs_node *node, int pos,
 	int log2blocksize = LOG2_EXT2_BLOCK_SIZE(node->data);
 	int blocksize = 1 << (log2blocksize + DISK_SECTOR_BITS);
 	unsigned int filesize = le32_to_cpu(node->inode.size);
-	int previous_block_number = -1;
-	int delayed_start = 0;
-	int delayed_extent = 0;
-	int delayed_skipfirst = 0;
-	int delayed_next = 0;
-	char *delayed_buf = NULL;
 	short ret;
 	struct ext_filesystem *fs = node->data->fs;
 
@@ -75,6 +69,7 @@ int ext4fs_read_file(struct ext2fs_node *node, int pos,
 		int blockoff = pos % blocksize;
 		int blockend = blocksize;
 		int skipfirst = 0;
+
 		blknr = read_allocated_block(node, i);
 		if (blknr < 0)
 			return blknr;
@@ -95,59 +90,17 @@ int ext4fs_read_file(struct ext2fs_node *node, int pos,
 			skipfirst = blockoff;
 			blockend -= skipfirst;
 		}
+
 		if (blknr) {
-			if (previous_block_number != -1) {
-				if (delayed_next == blknr) {
-					delayed_extent += blockend;
-					delayed_next += blockend >> SECTOR_BITS;
-				} else {	/* spill */
-					ret = ext4fs_devread(fs, delayed_start,
-							delayed_skipfirst,
-							delayed_extent,
-							delayed_buf);
-					if (ret)
-						return ret;
-					previous_block_number = blknr;
-					delayed_start = blknr;
-					delayed_extent = blockend;
-					delayed_skipfirst = skipfirst;
-					delayed_buf = buf;
-					delayed_next = blknr +
-						(blockend >> SECTOR_BITS);
-				}
-			} else {
-				previous_block_number = blknr;
-				delayed_start = blknr;
-				delayed_extent = blockend;
-				delayed_skipfirst = skipfirst;
-				delayed_buf = buf;
-				delayed_next = blknr +
-					(blockend >> SECTOR_BITS);
-			}
+			ret = ext4fs_devread(fs, blknr, skipfirst, blockend, buf);
+			if (ret)
+				return ret;
 		} else {
-			if (previous_block_number != -1) {
-				/* spill */
-				ret = ext4fs_devread(fs, delayed_start,
-							delayed_skipfirst,
-							delayed_extent,
-							delayed_buf);
-				if (ret)
-					return ret;
-				previous_block_number = -1;
-			}
-			memset(buf, 0, blocksize - skipfirst);
+			memset(buf, 0, blockend);
 		}
+
 		buf += blocksize - skipfirst;
 	}
-	if (previous_block_number != -1) {
-		/* spill */
-		ret = ext4fs_devread(fs, delayed_start,
-					delayed_skipfirst, delayed_extent,
-					delayed_buf);
-		if (ret)
-			return ret;
-		previous_block_number = -1;
-	}
 
 	return len;
 }