[PATCH 2/2] fs: exfat: Remove pointless variable uoffset

[Andrew Goodbody]

In exfat_generic_pread and exfat_generic_pwrite offset is passed in as a
off_t type which is defined as 'unsigned long long' so there is no need
to create the variable uoffset as a uint64_t as this is just a direct
copy of offset. Also remove the impossible test of 'offset < 0' as this
is always false due to offset being unsigned.

This issue found by Smatch.

Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>
---
 fs/exfat/io.c | 40 +++++++++++++++++-----------------------
 1 file changed, 17 insertions(+), 23 deletions(-)

diff --git a/fs/exfat/io.c b/fs/exfat/io.c
index d80eece6850..6c86688cd6c 100644
--- a/fs/exfat/io.c
+++ b/fs/exfat/io.c
@@ -479,43 +479,40 @@ ssize_t exfat_pwrite(struct exfat_dev* dev, const void* buffer, size_t size,
 ssize_t exfat_generic_pread(const struct exfat* ef, struct exfat_node* node,
 		void* buffer, size_t size, off_t offset)
 {
-	uint64_t uoffset = offset;
 	cluster_t cluster;
 	char* bufp = buffer;
 	off_t lsize, loffset, remainder;
 
-	if (offset < 0)
-		return -EINVAL;
-	if (uoffset >= node->size)
+	if (offset >= node->size)
 		return 0;
 	if (size == 0)
 		return 0;
 
-	if (uoffset + size > node->valid_size)
+	if (offset + size > node->valid_size)
 	{
 		ssize_t bytes = 0;
 
-		if (uoffset < node->valid_size)
+		if (offset < node->valid_size)
 		{
 			bytes = exfat_generic_pread(ef, node, buffer,
-					node->valid_size - uoffset, offset);
-			if (bytes < 0 || (size_t) bytes < node->valid_size - uoffset)
+					node->valid_size - offset, offset);
+			if (bytes < 0 || (size_t)bytes < node->valid_size - offset)
 				return bytes;
 		}
 		memset(buffer + bytes, 0,
 				MIN(size - bytes, node->size - node->valid_size));
-		return MIN(size, node->size - uoffset);
+		return MIN(size, node->size - offset);
 	}
 
-	cluster = exfat_advance_cluster(ef, node, uoffset / CLUSTER_SIZE(*ef->sb));
+	cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
 	if (CLUSTER_INVALID(*ef->sb, cluster))
 	{
 		exfat_error("invalid cluster 0x%x while reading", cluster);
 		return -EIO;
 	}
 
-	loffset = uoffset % CLUSTER_SIZE(*ef->sb);
-	remainder = MIN(size, node->size - uoffset);
+	loffset = offset % CLUSTER_SIZE(*ef->sb);
+	remainder = MIN(size, node->size - offset);
 	while (remainder > 0)
 	{
 		if (CLUSTER_INVALID(*ef->sb, cluster))
@@ -537,43 +534,40 @@ ssize_t exfat_generic_pread(const struct exfat* ef, struct exfat_node* node,
 	}
 	if (!(node->attrib & EXFAT_ATTRIB_DIR) && !ef->ro && !ef->noatime)
 		exfat_update_atime(node);
-	return MIN(size, node->size - uoffset) - remainder;
+	return MIN(size, node->size - offset) - remainder;
 }
 
 ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
 		const void* buffer, size_t size, off_t offset)
 {
-	uint64_t uoffset = offset;
 	int rc;
 	cluster_t cluster;
 	const char* bufp = buffer;
 	off_t lsize, loffset, remainder;
 
-	if (offset < 0)
-		return -EINVAL;
-	if (uoffset > node->size)
+	if (offset > node->size)
 	{
-		rc = exfat_truncate(ef, node, uoffset, true);
+		rc = exfat_truncate(ef, node, offset, true);
 		if (rc != 0)
 			return rc;
 	}
-	if (uoffset + size > node->size)
+	if (offset + size > node->size)
 	{
-		rc = exfat_truncate(ef, node, uoffset + size, false);
+		rc = exfat_truncate(ef, node, offset + size, false);
 		if (rc != 0)
 			return rc;
 	}
 	if (size == 0)
 		return 0;
 
-	cluster = exfat_advance_cluster(ef, node, uoffset / CLUSTER_SIZE(*ef->sb));
+	cluster = exfat_advance_cluster(ef, node, offset / CLUSTER_SIZE(*ef->sb));
 	if (CLUSTER_INVALID(*ef->sb, cluster))
 	{
 		exfat_error("invalid cluster 0x%x while writing", cluster);
 		return -EIO;
 	}
 
-	loffset = uoffset % CLUSTER_SIZE(*ef->sb);
+	loffset = offset % CLUSTER_SIZE(*ef->sb);
 	remainder = size;
 	while (remainder > 0)
 	{
@@ -592,7 +586,7 @@ ssize_t exfat_generic_pwrite(struct exfat* ef, struct exfat_node* node,
 		bufp += lsize;
 		loffset = 0;
 		remainder -= lsize;
-		node->valid_size = MAX(node->valid_size, uoffset + size - remainder);
+		node->valid_size = MAX(node->valid_size, offset + size - remainder);
 		cluster = exfat_next_cluster(ef, node, cluster);
 	}
 	if (!(node->attrib & EXFAT_ATTRIB_DIR))

-- 
2.39.5