freebsd-skq/sys/x86/iommu/busdma_dmar.h
kib 74b8996ebe Import the driver for VT-d DMAR hardware, as specified in the revision
1.3 of Intelб╝ Virtualization Technology for Directed I/O Architecture
Specification.  The Extended Context and PASIDs from the rev. 2.2 are
not supported, but I am not aware of any released hardware which
implements them.  Code does not use queued invalidation, see comments
for the reason, and does not provide interrupt remapping services.

Code implements the management of the guest address space per domain
and allows to establish and tear down arbitrary mappings, but not
partial unmapping.  The superpages are created as needed, but not
promoted.  Faults are recorded, fault records could be obtained
programmatically, and printed on the console.

Implement the busdma(9) using DMARs.  This busdma backend avoids
bouncing and provides security against misbehaving hardware and driver
bad programming, preventing leaks and corruption of the memory by wild
DMA accesses.

By default, the implementation is compiled into amd64 GENERIC kernel
but disabled; to enable, set hw.dmar.enable=1 loader tunable.  Code is
written to work on i386, but testing there was low priority, and
driver is not enabled in GENERIC.  Even with the DMAR turned on,
individual devices could be directed to use the bounce busdma with the
hw.busdma.pci<domain>:<bus>:<device>:<function>.bounce=1 tunable.  If
DMARs are capable of the pass-through translations, it is used,
otherwise, an identity-mapping page table is constructed.

The driver was tested on Xeon 5400/5500 chipset legacy machine,
Haswell desktop and E5 SandyBridge dual-socket boxes, with ahci(4),
ata(4), bce(4), ehci(4), mfi(4), uhci(4), xhci(4) devices.  It also
works with em(4) and igb(4), but there some fixes are needed for
drivers, which are not committed yet.  Intel GPUs do not work with
DMAR (yet).

Many thanks to John Baldwin, who explained me the newbus integration;
Peter Holm, who did all testing and helped me to discover and
understand several incredible bugs; and to Jim Harris for the access
to the EDS and BWG and for listening when I have to explain my
findings to somebody.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
2013-10-28 13:33:29 +00:00

66 lines
2.2 KiB
C

/*-
* Copyright (c) 2013 The FreeBSD Foundation
* All rights reserved.
*
* This software was developed by Konstantin Belousov <kib@FreeBSD.org>
* under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef __X86_IOMMU_BUSDMA_DMAR_H
#define __X86_IOMMU_BUSDMA_DMAR_H
struct dmar_map_entry;
TAILQ_HEAD(dmar_map_entries_tailq, dmar_map_entry);
struct bus_dma_tag_dmar {
struct bus_dma_tag_common common;
struct dmar_ctx *ctx;
device_t owner;
int map_count;
bus_dma_segment_t *segments;
};
struct bus_dmamap_dmar {
struct bus_dma_tag_dmar *tag;
struct memdesc mem;
bus_dmamap_callback_t *callback;
void *callback_arg;
struct dmar_map_entries_tailq map_entries;
TAILQ_ENTRY(bus_dmamap_dmar) delay_link;
bool locked;
bool cansleep;
int flags;
};
#define BUS_DMAMAP_DMAR_MALLOC 0x0001
#define BUS_DMAMAP_DMAR_KMEM_ALLOC 0x0002
extern struct bus_dma_impl bus_dma_dmar_impl;
bus_dma_tag_t dmar_get_dma_tag(device_t dev, device_t child);
#endif