5431 static int append_to_buffer(const char __user *ubp, struct osst_buffer *st_bp, int do_count)  in append_to_buffer()  argument
5435 	for (i=0, offset=st_bp->buffer_bytes;  in append_to_buffer()
5436 	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)  in append_to_buffer()
5437 		offset -= st_bp->sg[i].length;  in append_to_buffer()
5438 	if (i == st_bp->sg_segs) {  /* Should never happen */  in append_to_buffer()
5442 	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {  in append_to_buffer()
5443 		cnt = st_bp->sg[i].length - offset < do_count ?  in append_to_buffer()
5444 		      st_bp->sg[i].length - offset : do_count;  in append_to_buffer()
5445 		res = copy_from_user(page_address(sg_page(&st_bp->sg[i])) + offset, ubp, cnt);  in append_to_buffer()
5449 		st_bp->buffer_bytes += cnt;  in append_to_buffer()
5464 static int from_buffer(struct osst_buffer *st_bp, char __user *ubp, int do_count)  in from_buffer()  argument
5468 	for (i=0, offset=st_bp->read_pointer;  in from_buffer()
5469 	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)  in from_buffer()
5470 		offset -= st_bp->sg[i].length;  in from_buffer()
5471 	if (i == st_bp->sg_segs) {  /* Should never happen */  in from_buffer()
5475 	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {  in from_buffer()
5476 		cnt = st_bp->sg[i].length - offset < do_count ?  in from_buffer()
5477 		      st_bp->sg[i].length - offset : do_count;  in from_buffer()
5478 		res = copy_to_user(ubp, page_address(sg_page(&st_bp->sg[i])) + offset, cnt);  in from_buffer()
5482 		st_bp->buffer_bytes -= cnt;  in from_buffer()
5483 		st_bp->read_pointer += cnt;  in from_buffer()
5496 static int osst_zero_buffer_tail(struct osst_buffer *st_bp)  in osst_zero_buffer_tail()  argument
5500 	for (i = 0, offset = st_bp->buffer_bytes;  in osst_zero_buffer_tail()
5501 	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)  in osst_zero_buffer_tail()
5502 		offset -= st_bp->sg[i].length;  in osst_zero_buffer_tail()
5503 	if (i == st_bp->sg_segs) {  /* Should never happen */  in osst_zero_buffer_tail()
5507 	for (do_count = OS_DATA_SIZE - st_bp->buffer_bytes;  in osst_zero_buffer_tail()
5508 	     i < st_bp->sg_segs && do_count > 0; i++) {  in osst_zero_buffer_tail()
5509 		cnt = st_bp->sg[i].length - offset < do_count ?  in osst_zero_buffer_tail()
5510 		      st_bp->sg[i].length - offset : do_count ;  in osst_zero_buffer_tail()
5511 		memset(page_address(sg_page(&st_bp->sg[i])) + offset, 0, cnt);  in osst_zero_buffer_tail()
5524 static int osst_copy_to_buffer(struct osst_buffer *st_bp, unsigned char *ptr)  in osst_copy_to_buffer()  argument
5528 	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {  in osst_copy_to_buffer()
5529 		cnt = st_bp->sg[i].length < do_count ?  in osst_copy_to_buffer()
5530 		      st_bp->sg[i].length : do_count ;  in osst_copy_to_buffer()
5531 		memcpy(page_address(sg_page(&st_bp->sg[i])), ptr, cnt);  in osst_copy_to_buffer()
5535 	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */  in osst_copy_to_buffer()
5545 static int osst_copy_from_buffer(struct osst_buffer *st_bp, unsigned char *ptr)  in osst_copy_from_buffer()  argument
5549 	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {  in osst_copy_from_buffer()
5550 		cnt = st_bp->sg[i].length < do_count ?  in osst_copy_from_buffer()
5551 		      st_bp->sg[i].length : do_count ;  in osst_copy_from_buffer()
5552 		memcpy(ptr, page_address(sg_page(&st_bp->sg[i])), cnt);  in osst_copy_from_buffer()
5556 	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */  in osst_copy_from_buffer()