1 files changed, 47 insertions, 34 deletions

diff --git a/fs/ext2/xip.c b/fs/ext2/xip.c
index d44431d..0aa5ac1 100644
--- a/fs/ext2/xip.c
+++ b/fs/ext2/xip.c
@@ -15,66 +15,79 @@
 #include "xip.h"
 
 static inline int
-__inode_direct_access(struct inode *inode, sector_t sector, unsigned long *data) {
+__inode_direct_access(struct inode *inode, sector_t sector,
+		      unsigned long *data)
+{
 	BUG_ON(!inode->i_sb->s_bdev->bd_disk->fops->direct_access);
 	return inode->i_sb->s_bdev->bd_disk->fops
 		->direct_access(inode->i_sb->s_bdev,sector,data);
 }
 
+static inline int
+__ext2_get_sector(struct inode *inode, sector_t offset, int create,
+		   sector_t *result)
+{
+	struct buffer_head tmp;
+	int rc;
+
+	memset(&tmp, 0, sizeof(struct buffer_head));
+	rc = ext2_get_block(inode, offset/ (PAGE_SIZE/512), &tmp,
+			    create);
+	*result = tmp.b_blocknr;
+
+	/* did we get a sparse block (hole in the file)? */
+	if (!(*result)) {
+		BUG_ON(create);
+		rc = -ENODATA;
+	}
+
+	return rc;
+}
+
 int
-ext2_clear_xip_target(struct inode *inode, int block) {
-	sector_t sector = block*(PAGE_SIZE/512);
+ext2_clear_xip_target(struct inode *inode, int block)
+{
+	sector_t sector = block * (PAGE_SIZE/512);
 	unsigned long data;
 	int rc;
 
 	rc = __inode_direct_access(inode, sector, &data);
-	if (rc)
-		return rc;
-	clear_page((void*)data);
-	return 0;
+	if (!rc)
+		clear_page((void*)data);
+	return rc;
 }
 
 void ext2_xip_verify_sb(struct super_block *sb)
 {
 	struct ext2_sb_info *sbi = EXT2_SB(sb);
 
-	if ((sbi->s_mount_opt & EXT2_MOUNT_XIP)) {
-		if ((sb->s_bdev == NULL) ||
-			sb->s_bdev->bd_disk == NULL ||
-			sb->s_bdev->bd_disk->fops == NULL ||
-			sb->s_bdev->bd_disk->fops->direct_access == NULL) {
-			sbi->s_mount_opt &= (~EXT2_MOUNT_XIP);
-			ext2_warning(sb, __FUNCTION__,
-				"ignoring xip option - not supported by bdev");
-		}
+	if ((sbi->s_mount_opt & EXT2_MOUNT_XIP) &&
+	    !sb->s_bdev->bd_disk->fops->direct_access) {
+		sbi->s_mount_opt &= (~EXT2_MOUNT_XIP);
+		ext2_warning(sb, __FUNCTION__,
+			     "ignoring xip option - not supported by bdev");
 	}
 }
 
-struct page*
-ext2_get_xip_page(struct address_space *mapping, sector_t blockno,
+struct page *
+ext2_get_xip_page(struct address_space *mapping, sector_t offset,
 		   int create)
 {
 	int rc;
 	unsigned long data;
-	struct buffer_head tmp;
+	sector_t sector;
 
-	tmp.b_state = 0;
-	tmp.b_blocknr = 0;
-	rc = ext2_get_block(mapping->host, blockno/(PAGE_SIZE/512) , &tmp,
-				create);
+	/* first, retrieve the sector number */
+	rc = __ext2_get_sector(mapping->host, offset, create, &sector);
 	if (rc)
-		return ERR_PTR(rc);
-	if (tmp.b_blocknr == 0) {
-		/* SPARSE block */
-		BUG_ON(create);
-		return ERR_PTR(-ENODATA);
-	}
+		goto error;
 
+	/* retrieve address of the target data */
 	rc = __inode_direct_access
-		(mapping->host,tmp.b_blocknr*(PAGE_SIZE/512) ,&data);
-	if (rc)
-		return ERR_PTR(rc);
+		(mapping->host, sector * (PAGE_SIZE/512), &data);
+	if (!rc)
+		return virt_to_page(data);
 
-	SetPageUptodate(virt_to_page(data));
-	return virt_to_page(data);
+ error:
+	return ERR_PTR(rc);
 }