From c08ef9a777d3bec4deaad564bcf510e8f0b27ff6 Mon Sep 17 00:00:00 2001 From: Kevin O'Connor Date: Mon, 29 Dec 2014 10:15:57 -0500 Subject: cdrom: Break up very large read requests into smaller requests A cdrom boot image could be over 64K in size, but the low level drivers may not support very large reads. If a large cdrom image is found, issue multiple reads so that a read request over 64K is never issued. Signed-off-by: Kevin O'Connor --- src/cdrom.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/src/cdrom.c b/src/cdrom.c index de0e7de..92f34f4 100644 --- a/src/cdrom.c +++ b/src/cdrom.c @@ -212,12 +212,21 @@ cdrom_boot(struct drive_s *drive) CDEmu.device_spec = drive->cntl_id % 2; // And we read the image in memory + nbsectors = DIV_ROUND_UP(nbsectors, 4); dop.lba = lba; - dop.count = DIV_ROUND_UP(nbsectors, 4); dop.buf_fl = MAKE_FLATPTR(boot_segment, 0); - ret = scsi_process_op(&dop); - if (ret) - return 12; + while (nbsectors) { + int count = nbsectors; + if (count > 64*1024/CDROM_SECTOR_SIZE) + count = 64*1024/CDROM_SECTOR_SIZE; + dop.count = count; + ret = scsi_process_op(&dop); + if (ret) + return 12; + nbsectors -= count; + dop.lba += count; + dop.buf_fl += count*CDROM_SECTOR_SIZE; + } if (media == 0) { // No emulation requested - return success. -- cgit v1.1