diff options
Diffstat (limited to 'hw/ide/ahci.c')
| -rw-r--r-- | hw/ide/ahci.c | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c index 21f76ed86e..f547ebb46c 100644 --- a/hw/ide/ahci.c +++ b/hw/ide/ahci.c @@ -804,8 +804,21 @@ static int prdt_tbl_entry_size(const AHCI_SG *tbl) return (le32_to_cpu(tbl->flags_size) & AHCI_PRDT_SIZE_MASK) + 1; } +/** + * Fetch entries in a guest-provided PRDT and convert it into a QEMU SGlist. + * @ad: The AHCIDevice for whom we are building the SGList. + * @sglist: The SGList target to add PRD entries to. + * @cmd: The AHCI Command Header that describes where the PRDT is. + * @limit: The remaining size of the S/ATA transaction, in bytes. + * @offset: The number of bytes already transferred, in bytes. + * + * The AHCI PRDT can describe up to 256GiB. S/ATA only support transactions of + * up to 32MiB as of ATA8-ACS3 rev 1b, assuming a 512 byte sector size. We stop + * building the sglist from the PRDT as soon as we hit @limit bytes, + * which is <= INT32_MAX/2GiB. + */ static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist, - AHCICmdHdr *cmd, int64_t limit, int32_t offset) + AHCICmdHdr *cmd, int64_t limit, uint64_t offset) { uint16_t opts = le16_to_cpu(cmd->opts); uint16_t prdtl = le16_to_cpu(cmd->prdtl); @@ -823,14 +836,6 @@ static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist, IDEBus *bus = &ad->port; BusState *qbus = BUS(bus); - /* - * Note: AHCI PRDT can describe up to 256GiB. SATA/ATA only support - * transactions of up to 32MiB as of ATA8-ACS3 rev 1b, assuming a - * 512 byte sector size. We limit the PRDT in this implementation to - * a reasonably large 2GiB, which can accommodate the maximum transfer - * request for sector sizes up to 32K. - */ - if (!prdtl) { DPRINTF(ad->port_no, "no sg list given by guest: 0x%08x\n", opts); return -1; @@ -880,13 +885,6 @@ static int ahci_populate_sglist(AHCIDevice *ad, QEMUSGList *sglist, qemu_sglist_add(sglist, le64_to_cpu(tbl[i].addr), MIN(prdt_tbl_entry_size(&tbl[i]), limit - sglist->size)); - if (sglist->size > INT32_MAX) { - error_report("AHCI Physical Region Descriptor Table describes " - "more than 2 GiB."); - qemu_sglist_destroy(sglist); - r = -1; - goto out; - } } } |