Commit Graph

15 Commits

Author SHA1 Message Date
Konstantin Belousov
1abfd35537 Split the DMAR unit domains and contexts. Domains carry address space
and related data structures.  Contexts attach requests initiators to
domains.  There is still 1:1 correspondence between contexts and
domains on the running system, since only busdma currently allocates
them, using dmar_get_ctx_for_dev().

Large part of the change is formal rename of the ctx to domain, but
patch also reworks the context allocation and free to allow for
independent domain creation.

The helper dmar_move_ctx_to_domain() is introduced for future use, to
reassign request initiator from one domain to another.  The hard issue
which is not yet resolved with the context move is proper handling (or
reserving) RMRR entries in the destination domain as required by ACPI
DMAR table for moved context.

Tested by:	pho
Sponsored by:	The FreeBSD Foundation
2015-06-26 07:01:29 +00:00
Konstantin Belousov
69baeadc31 Remove several write-only variables, all reported by the gcc 4.9
buildkernel run.

Some of them were write-only under some kernel options, e.g. variables
keeping values only used by CTR() macros.  It costs nothing to the
code readability and correctness to eliminate the warnings in those
cases too by removing the local cached values used only for
single-access.

Review:	https://reviews.freebsd.org/D2665
Reviewed by:	rodrigc
Looked at by:	bjk
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-05-29 13:24:17 +00:00
Konstantin Belousov
5f01ba81ae Account for the offset of the page run when allocating the
dmar_map_entry.  Non-zero offset both increases the required mapping
size, which is handled in dmar_bus_dmamap_load_something1(), and makes
it possible that allocated range crosses boundary, which needs a check
in dmar_gas_match_one().

Reported and tested by:	jimharris
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-08 01:55:22 +00:00
Konstantin Belousov
0a110d5b17 Use VT-d interrupt remapping block (IR) to perform FSB messages
translation.  In particular, despite IO-APICs only take 8bit apic id,
IR translation structures accept 32bit APIC Id, which allows x2APIC
mode to function properly.  Extend msi_cpu of struct msi_intrsrc and
io_cpu of ioapic_intsrc to full int from one byte.

KPI of IR is isolated into the x86/iommu/iommu_intrmap.h, to avoid
bringing all dmar headers into interrupt code. The non-PCI(e) devices
which generate message interrupts on FSB require special handling. The
HPET FSB interrupts are remapped, while DMAR interrupts are not.

For each msi and ioapic interrupt source, the iommu cookie is added,
which is in fact index of the IRE (interrupt remap entry) in the IR
table. Cookie is made at the source allocation time, and then used at
the map time to fill both IRE and device registers. The MSI
address/data registers and IO-APIC redirection registers are
programmed with the special values which are recognized by IR and used
to restore the IRE index, to find proper delivery mode and target.
Map all MSI interrupts in the block when msi_map() is called.

Since an interrupt source setup and dismantle code are done in the
non-sleepable context, flushing interrupt entries cache in the IR
hardware, which is done async and ideally waits for the interrupt,
requires busy-wait for queue to drain.  The dmar_qi_wait_for_seq() is
modified to take a boolean argument requesting busy-wait for the
written sequence number instead of waiting for interrupt.

Some interrupts are configured before IR is initialized, e.g. ACPI
SCI.  Add intr_reprogram() function to reprogram all already
configured interrupts, and call it immediately before an IR unit is
enabled.  There is still a small window after the IO-APIC redirection
entry is reprogrammed with cookie but before the unit is enabled, but
to fix this properly, IR must be started much earlier.

Add workarounds for 5500 and X58 northbridges, some revisions of which
have severe flaws in handling IR.  Use the same identification methods
as employed by Linux.

Review:	https://reviews.freebsd.org/D1892
Reviewed by:	neel
Discussed with:	jhb
Tested by:	glebius, pho (previous versions)
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
2015-03-19 13:57:47 +00:00
Konstantin Belousov
af02586229 Revert r276949 and redo the fix for PCIe/PCI bridges, which do not
follow specification and do not provide PCIe capability.

Verify if the port above such bridge is downstream PCIe (or root port)
and treat the bridge as PCIe/PCI then.  This allows to avoid
maintaining the table of device ids for bridges without capability,
while still calculate correct request originator for devices behind
the bridge.

Submitted by:	Jason Harmening <jason.harmening@gmail.com>
MFC after:	1 week
2015-02-21 22:38:32 +00:00
Konstantin Belousov
df0b07834f Fix calculation of requester for PCI device behind PCIe/PCI bridge.
In my case on the test machine, I have hierarchy of
pcib2 (PCIe port on host bridge with PCIe capability) -> pci2 ->
    pcib3 (ITE PCIe/PCI bridge) -> pci3 -> em1

The device to check PCIe capability is pcib2 and not pcib3, as it is
currently done in the code.  Also, in case of the bridge, we shall
step to pcib2 for the loop iteration, since pcib3 does not carry PCIe
capability info and would force wrong recalculation of rid.

Also change the returned requester to the PCIe bus which provides port
for the bridge.  This only results in changing
hw.busdma.pciX.X.X.X.bounce tunable to force identity-mapped context
for the device.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-01-10 23:12:49 +00:00
Davide Italiano
2be111bf7d Follow up to r225617. In order to maximize the re-usability of kernel code
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.

Submitted by:   kmacy
Tested by:      make universe
2014-10-16 18:04:43 +00:00
Ryan Stone
6749935455 Re-implement the DMAR I/O MMU code in terms of PCI RIDs
Under the hood the VT-d spec is really implemented in terms of
PCI RIDs instead of bus/slot/function, even though the spec makes
pains to convert back to bus/slot/function in examples.  However
working with bus/slot/function is not correct when PCI ARI is
in use, so convert to using RIDs in most cases.  bus/slot/function
will only be used when reporting errors to a user.

Reviewed by:	kib
MFC after:	2 months
Sponsored by:	Sandvine Inc.
2014-04-01 15:48:46 +00:00
Ryan Stone
7036ae46bf Revert PCI RID changes.
My PCI RID changes somehow got intermixed with my PCI ARI patch when I
committed it.  I may have accidentally applied a patch to a non-clean
working tree.  Revert everything while I figure out what went wrong.

Pointy hat to: rstone
2014-04-01 15:06:03 +00:00
Ryan Stone
b5eb8abe3e Re-implement the DMAR I/O MMU code in terms of PCI RIDs
Under the hood the VT-d spec is really implemented in terms of
PCI RIDs instead of bus/slot/function, even though the spec makes
pains to convert back to bus/slot/function in examples.  However
working with bus/slot/function is not correct when PCI ARI is
in use, so convert to using RIDs in most cases.  bus/slot/function
will only be used when reporting errors to a user.

Reviewed by:	kib
Sponsored by:	Sandvine Inc.
2014-04-01 14:51:45 +00:00
Konstantin Belousov
9d0bc6d88f Add support for the PCI(e)-PCI bridges to the Intel VT-d driver. The
bridge takes ownership of the transaction, so bsf of the requester is
the bridge and not a device behind it.  As result, code needs to walk
the hierarchy up to use correct context.

Note that PCIe->PCI-X bridges are not handled quite correctly since
such bridges are allowed to only take ownership of some transactions.
Also, weird but unrealistic cases of PCIe behind PCI bus are also not
handled.

Still, the patch provides significant step forward for the bridge
handling.

Submitted by:	Jason Harmening <jason.harmening@gmail.com>
MFC after:	1 week
2014-03-18 16:41:32 +00:00
Konstantin Belousov
e8c5884213 Trim at EOL.
MFC after:	3 days
2014-03-18 15:59:06 +00:00
Dimitry Andric
e7d8b7e43f Initialize variable in sys/x86/iommu/busdma_dmar.c, to avoid possible
uninitialized use.

Reviewed by:	kib
2013-11-08 17:27:22 +00:00
Konstantin Belousov
06d513424a Remove redundand assignment to error variable and check for its value [1].
Do CTR logging in the case of error as well.

Noted by:	rdivacky [1]
Sponsored by:	The FreeBSD Foundation
MFC after:	1 month
2013-10-28 19:30:09 +00:00
Konstantin Belousov
86be9f0dd5 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