@@ -777,7 +777,7 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
volume_info volinfo;
fsdata datablock;
fsdata *mydata = &datablock;
- dir_entry *dentptr;
+ dir_entry *dentptr = NULL;
__u16 prevcksum = 0xffff;
char *subname = "";
__u32 cursect;
@@ -876,19 +876,21 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
while (1) {
int i;
- debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
- cursect, mydata->clust_size, DIRENTSPERBLOCK);
+ if (j == 0) {
+ debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
+ cursect, mydata->clust_size, DIRENTSPERBLOCK);
- if (disk_read(cursect,
- (mydata->fatsize == 32) ?
- (mydata->clust_size) :
- PREFETCH_BLOCKS,
- do_fat_read_block) < 0) {
- debug("Error: reading rootdir block\n");
- goto exit;
- }
+ if (disk_read(cursect,
+ (mydata->fatsize == 32) ?
+ (mydata->clust_size) :
+ PREFETCH_BLOCKS,
+ do_fat_read_block) < 0) {
+ debug("Error: reading rootdir block\n");
+ goto exit;
+ }
- dentptr = (dir_entry *) do_fat_read_block;
+ dentptr = (dir_entry *) do_fat_read_block;
+ }
for (i = 0; i < DIRENTSPERBLOCK; i++) {
char s_name[14], l_name[VFAT_MAXLEN_BYTES];
@@ -1030,28 +1032,33 @@ do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
* completely processed.
*/
++j;
- int fat32_end = 0;
- if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
- int nxtsect = 0;
- int nxt_clust = 0;
+ int rootdir_end = 0;
+ if (mydata->fatsize == 32) {
+ if (j == mydata->clust_size) {
+ int nxtsect = 0;
+ int nxt_clust = 0;
- nxt_clust = get_fatent(mydata, root_cluster);
- fat32_end = CHECK_CLUST(nxt_clust, 32);
+ nxt_clust = get_fatent(mydata, root_cluster);
+ rootdir_end = CHECK_CLUST(nxt_clust, 32);
- nxtsect = mydata->data_begin +
- (nxt_clust * mydata->clust_size);
+ nxtsect = mydata->data_begin +
+ (nxt_clust * mydata->clust_size);
- root_cluster = nxt_clust;
+ root_cluster = nxt_clust;
- cursect = nxtsect;
- j = 0;
+ cursect = nxtsect;
+ j = 0;
+ }
} else {
- cursect++;
+ if (j == PREFETCH_BLOCKS)
+ j = 0;
+
+ rootdir_end = (++cursect - mydata->rootdir_sect >=
+ rootdir_size);
}
/* If end of rootdir reached */
- if ((mydata->fatsize == 32 && fat32_end) ||
- (mydata->fatsize != 32 && j == rootdir_size)) {
+ if (rootdir_end) {
if (dols == LS_ROOT) {
printf("\n%d file(s), %d dir(s)\n\n",
files, dirs);
With the previous code, the remaining prefetched sectors were read again after each sector. With this patch, each sector is read only once, thus making the prefetch useful. Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com> Cc: Wolfgang Denk <wd@denx.de> --- .../fs/fat/fat.c | 59 +++++++++++--------- 1 file changed, 33 insertions(+), 26 deletions(-)