fs: fat: dynamically allocate memory for temporary buffer

Drop the statically allocated get_contents_vfatname_block and
dynamically allocate a buffer only if required. This saves
64KiB of memory.

Signed-off-by: Stefan Agner <stefan.ag...@toradex.com>
Signed-off-by: Tien Fong Chee <tien.fong.chee@intel.com>
This commit is contained in:
Tien Fong Chee 2019-02-11 14:56:19 +08:00 committed by Tom Rini
parent dae5c2dcdc
commit 8537874a65

View File

@ -306,9 +306,6 @@ get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
* into 'buffer'.
* Update the number of bytes read in *gotsize or return -1 on fatal errors.
*/
__u8 get_contents_vfatname_block[MAX_CLUSTSIZE]
__aligned(ARCH_DMA_MINALIGN);
static int get_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos,
__u8 *buffer, loff_t maxsize, loff_t *gotsize)
{
@ -351,15 +348,24 @@ static int get_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos,
/* align to beginning of next cluster if any */
if (pos) {
__u8 *tmp_buffer;
actsize = min(filesize, (loff_t)bytesperclust);
if (get_cluster(mydata, curclust, get_contents_vfatname_block,
(int)actsize) != 0) {
tmp_buffer = malloc_cache_aligned(actsize);
if (!tmp_buffer) {
debug("Error: allocating buffer\n");
return -ENOMEM;
}
if (get_cluster(mydata, curclust, tmp_buffer, actsize) != 0) {
printf("Error reading cluster\n");
free(tmp_buffer);
return -1;
}
filesize -= actsize;
actsize -= pos;
memcpy(buffer, get_contents_vfatname_block + pos, actsize);
memcpy(buffer, tmp_buffer + pos, actsize);
free(tmp_buffer);
*gotsize += actsize;
if (!filesize)
return 0;