fs/sysv: Use the offset_in_page() helper

Use the offset_in_page() helper because it is more suitable than doing
explicit subtractions between pointers to directory entries and kernel
virtual addresses of mapped pages.

Cc: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index 1673079..0edd18e 100644 (file)
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -211,8 +211,7 @@ int sysv_add_link(struct dentry *dentry, struct inode *inode)
        return -EINVAL;
 
 got_it:
-       pos = page_offset(page) +
-                       (char*)de - (char*)page_address(page);
+       pos = page_offset(page) + offset_in_page(de);
        lock_page(page);
        err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
        if (err)
@@ -236,8 +235,7 @@ out_unlock:
 int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page)
 {
        struct inode *inode = page->mapping->host;
-       char *kaddr = (char*)page_address(page);
-       loff_t pos = page_offset(page) + (char *)de - kaddr;
+       loff_t pos = page_offset(page) + offset_in_page(de);
        int err;
 
        lock_page(page);
@@ -335,8 +333,7 @@ void sysv_set_link(struct sysv_dir_entry *de, struct page *page,
        struct inode *inode)
 {
        struct inode *dir = page->mapping->host;
-       loff_t pos = page_offset(page) +
-                       (char *)de-(char*)page_address(page);
+       loff_t pos = page_offset(page) + offset_in_page(de);
        int err;
 
        lock_page(page);