libsa/zfs/zfs.c

462 	unsigned secsz, do_tail_read;
470 	ret = ioctl(fd, DIOCGSECTORSIZE, &secsz);
495 	 *              |<------total_size = secsz----->|
503 	start_sec = offset / secsz;
504 	head = offset % secsz;
505 	total_size = roundup2(head + bytes, secsz);
507 	do_tail_read = ((tail > 0) && (head + bytes > secsz));
510 		full_sec_size -= secsz;
512 		full_sec_size -= secsz;
515 	if ((head > 0) || do_tail_read || bytes < secsz) {
516 		bouncebuf = malloc(secsz);
523 	if (lseek(fd, start_sec * secsz, SEEK_SET) == -1) {
530 		res = read(fd, bouncebuf, secsz);
531 		if (res != secsz) {
535 		memcpy(outbuf, bouncebuf + head, min(secsz - head, bytes));
536 		outbuf += min(secsz - head, bytes);
547 			res = read(fd, bouncebuf, secsz);
548 			if (res != secsz) {
565 		res = read(fd, bouncebuf, secsz);
566 		if (res != secsz) {
570 		memcpy(outbuf, bouncebuf, secsz - tail);
584 	unsigned secsz, do_tail_write;
593 	ret = ioctl(fd, DIOCGSECTORSIZE, &secsz);
597 	start_sec = offset / secsz;
598 	head = offset % secsz;
599 	total_size = roundup2(head + bytes, secsz);
601 	do_tail_write = ((tail > 0) && (head + bytes > secsz));
604 		full_sec_size -= secsz;
606 		full_sec_size -= secsz;
609 	if ((head > 0) || do_tail_write || bytes < secsz) {
610 		bouncebuf = malloc(secsz);
617 	if (lseek(fd, start_sec * secsz, SEEK_SET) == -1) {
624 		res = read(fd, bouncebuf, secsz);
625 		if ((unsigned)res != secsz) {
629 		memcpy(bouncebuf + head, outbuf, min(secsz - head, bytes));
630 		(void) lseek(fd, -secsz, SEEK_CUR);
631 		res = write(fd, bouncebuf, secsz);
632 		if ((unsigned)res != secsz) {
636 		outbuf += min(secsz - head, bytes);
647 			res = read(fd, bouncebuf, secsz);
648 			if ((unsigned)res != secsz) {
653 			(void) lseek(fd, -secsz, SEEK_CUR);
654 			res = write(fd, bouncebuf, secsz);
655 			if ((unsigned)res != secsz) {
671 		res = read(fd, bouncebuf, secsz);
672 		if ((unsigned)res != secsz) {
676 		memcpy(bouncebuf, outbuf, secsz - tail);
677 		(void) lseek(fd, -secsz, SEEK_CUR);
678 		res = write(fd, bouncebuf, secsz);
679 		if ((unsigned)res != secsz) {
723 	u_int		secsz;
733 	    offset * ppa->secsz, buf, blocks * ppa->secsz));
778 		pa.secsz = ppa->secsz;
780 		    ppa->secsz, zfs_diskread);
1491 		ret = ioctl(pa.fd, DIOCGSECTORSIZE, &pa.secsz);
1495 		table = ptable_open(&pa, mediasz / pa.secsz, pa.secsz,