minix/u-boot
1
0
Fork 0
mirror of https://github.com/Stichting-MINIX-Research-Foundation/u-boot.git synced 2025-09-17 16:07:46 -04:00
Code Issues Packages Projects Releases Wiki Activity

FAT: Fix redundant sector read

Browse Source 
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>
This commit is contained in:
Benoît Thébaudeau 2012-07-20 15:20:12 +02:00 committed by Wolfgang Denk
parent 88503ad3bb
commit cd1b042c5c
1 changed files with 33 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
fs/fat/fat.c
View File

@ -775,7 +775,7 @@ do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
volume_info volinfo;
fsdata datablock;
fsdata *mydata = &datablock;
dir_entry *dentptr;
dir_entry *dentptr = NULL;
__u16 prevcksum = 0xffff;
char *subname = "";
__u32 cursect;
@ -874,6 +874,7 @@ do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
while (1) {
int i;
if (j == 0) {
debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
cursect, mydata->clust_size, DIRENTSPERBLOCK);
@ -887,6 +888,7 @@ do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
}
dentptr = (dir_entry *) do_fat_read_block;
}
for (i = 0; i < DIRENTSPERBLOCK; i++) {
char s_name[14], l_name[VFAT_MAXLEN_BYTES];
@ -1028,13 +1030,14 @@ do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
* completely processed.
*/
++j;
int fat32_end = 0;
if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
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);
rootdir_end = CHECK_CLUST(nxt_clust, 32);
nxtsect = mydata->data_begin +
(nxt_clust * mydata->clust_size);
@ -1043,13 +1046,17 @@ do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
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);