fs/fat: Clean up open-coded sector <-> cluster conversions

Use the clust_to_sect() helper that was introduced earlier, and add an
inverse sect_to_clust(), plus update the various spots that open-coded
this conversion previously.

Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 65873a2c2a86c8738d6157c93f3921e017b9b2c5..f5f74c12fffb9552ee59ace35f2caeb4f9d22cf4 100644 (file)
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -257,8 +257,7 @@ get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
        int ret;
 
        if (clustnum > 0) {
-               startsect = mydata->data_begin +
-                               clustnum * mydata->clust_size;
+               startsect = clust_to_sect(mydata, clustnum);
        } else {
                startsect = mydata->rootdir_sect;
        }
@@ -594,9 +593,8 @@ static int get_fs_info(fsdata *mydata)
                mydata->data_begin = mydata->rootdir_sect +
                                        mydata->rootdir_size -
                                        (mydata->clust_size * 2);
-               mydata->root_cluster = (mydata->rootdir_sect -
-                                       mydata->data_begin) /
-                                       mydata->clust_size;
+               mydata->root_cluster =
+                       sect_to_clust(mydata, mydata->rootdir_sect);
        }
 
        mydata->fatbufnum = -1;

diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index d0468baf8ff5766f8508b18f9dc341b36e7d54eb..9d2e0ed74c8c7ced6e42759c5f0e39de5349d828 100644 (file)
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -502,8 +502,7 @@ set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
        int ret;
 
        if (clustnum > 0)
-               startsect = mydata->data_begin +
-                               clustnum * mydata->clust_size;
+               startsect = clust_to_sect(mydata, clustnum);
        else
                startsect = mydata->rootdir_sect;
 
@@ -751,8 +750,7 @@ static int check_overflow(fsdata *mydata, __u32 clustnum, loff_t size)
        __u32 startsect, sect_num, offset;
 
        if (clustnum > 0) {
-               startsect = mydata->data_begin +
-                               clustnum * mydata->clust_size;
+               startsect = clust_to_sect(mydata, clustnum);
        } else {
                startsect = mydata->rootdir_sect;
        }
@@ -791,7 +789,7 @@ static dir_entry *empty_dentptr;
 static dir_entry *find_directory_entry(fsdata *mydata, int startsect,
        char *filename, dir_entry *retdent, __u32 start)
 {
-       __u32 curclust = (startsect - mydata->data_begin) / mydata->clust_size;
+       __u32 curclust = sect_to_clust(mydata, startsect);
 
        debug("get_dentfromdir: %s\n", filename);
 

diff --git a/include/fat.h b/include/fat.h
index 0f589391242f7b7d5dfe03e56125b1afc685df76..bdeda95e6debebad99523451efdcc14f584d7e44 100644 (file)
--- a/include/fat.h
+++ b/include/fat.h
@@ -177,12 +177,16 @@ typedef struct {
        __u32   root_cluster;   /* First cluster of root dir for FAT32 */
 } fsdata;
 
-/* TODO clean up places that are open-coding this: */
 static inline u32 clust_to_sect(fsdata *fsdata, u32 clust)
 {
        return fsdata->data_begin + clust * fsdata->clust_size;
 }
 
+static inline u32 sect_to_clust(fsdata *fsdata, u32 sect)
+{
+       return (sect - fsdata->data_begin) / fsdata->clust_size;
+}
+
 int file_fat_detectfs(void);
 int fat_exists(const char *filename);
 int fat_size(const char *filename, loff_t *size);