uint16_t isn't enough to hold the real sector count, since a value of
zero implies a full 64K sectors, so we need a uint32_t here.
We *could* cheat and pretend that this value is 0-based and fit it in
a uint16_t, but I'd rather waste 2 bytes instead of a future dev's
10 minutes when they forget to +1/-1 accordingly somewhere.
See SATA 3.2, section 13.6.4.1 "READ FPDMA QUEUED".
Signed-off-by: John Snow <js...@redhat.com>
---
hw/ide/ahci.c | 7 +++++--
hw/ide/ahci.h | 2 +-
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 7fcc6a2..043b959 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1085,8 +1085,11 @@ static void process_ncq_command(AHCIState *s, int port,
uint8_t *cmd_fis,
DPRINTF(port, "Warn: Unsupported attempt to use Rebuild Assist\n");
}
- ncq_tfs->sector_count = ((uint16_t)ncq_fis->sector_count_high << 8) |
- ncq_fis->sector_count_low;
+ ncq_tfs->sector_count = ((ncq_fis->sector_count_high << 8) |
+ ncq_fis->sector_count_low);
+ if (!ncq_tfs->sector_count) {
+ ncq_tfs->sector_count = 0x10000;
+ }
size = ncq_tfs->sector_count * 512;
ahci_populate_sglist(ad, &ncq_tfs->sglist, size, 0);
diff --git a/hw/ide/ahci.h b/hw/ide/ahci.h
index c728e3a..9090d3d 100644
--- a/hw/ide/ahci.h
+++ b/hw/ide/ahci.h
@@ -256,7 +256,7 @@ typedef struct NCQTransferState {
BlockAIOCB *aiocb;
QEMUSGList sglist;
BlockAcctCookie acct;
- uint16_t sector_count;
+ uint32_t sector_count;
uint64_t lba;
uint8_t tag;
uint8_t cmd;
--
2.1.0
