freebsd-dev/sys/x86/iommu/intel_qi.c
Konstantin Belousov cf619a92d2 Fix batched unload for DMAR busdma in qi mode.
Do not queue dmar_map_entries with zeroed gseq to
dmar_qi_invalidate_locked().  Zero gseq stops the processing in the qi
task.  Do not assign possibly uninitialized on-stack gseq to map
entries when requeuing them on unit tlb_flush queue.  Random garbage
in gsec is interpreted as too high invalidation sequence number and
again stop the processing in the task.

Make the sequence numbers generation completely contained in
dmar_qi_invalidate_locked() and dmar_qi_emit_wait_seq().  Upper code
directly passes boolean requesting emiting wait command instead of
trying to provide hint to avoid it by passing NULL gseq pointer.

Microoptimize the requeueing to tlb_flush queue by doing it for the
whole queue.

Diagnosed and tested by:	Brett Gutstein <bgutstein@rice.edu>
Discussed with:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2017-06-19 21:48:52 +00:00

473 lines
13 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_acpi.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/memdesc.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/taskqueue.h>
#include <sys/time.h>
#include <sys/tree.h>
#include <sys/vmem.h>
#include <machine/bus.h>
#include <contrib/dev/acpica/include/acpi.h>
#include <contrib/dev/acpica/include/accommon.h>
#include <dev/acpica/acpivar.h>
#include <vm/vm.h>
#include <vm/vm_extern.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <machine/cpu.h>
#include <x86/include/busdma_impl.h>
#include <x86/iommu/intel_reg.h>
#include <x86/iommu/busdma_dmar.h>
#include <x86/iommu/intel_dmar.h>
static bool
dmar_qi_seq_processed(const struct dmar_unit *unit,
const struct dmar_qi_genseq *pseq)
{
return (pseq->gen < unit->inv_waitd_gen ||
(pseq->gen == unit->inv_waitd_gen &&
pseq->seq <= unit->inv_waitd_seq_hw));
}
static int
dmar_enable_qi(struct dmar_unit *unit)
{
int error;
DMAR_ASSERT_LOCKED(unit);
unit->hw_gcmd |= DMAR_GCMD_QIE;
dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
!= 0));
return (error);
}
static int
dmar_disable_qi(struct dmar_unit *unit)
{
int error;
DMAR_ASSERT_LOCKED(unit);
unit->hw_gcmd &= ~DMAR_GCMD_QIE;
dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
== 0));
return (error);
}
static void
dmar_qi_advance_tail(struct dmar_unit *unit)
{
DMAR_ASSERT_LOCKED(unit);
dmar_write4(unit, DMAR_IQT_REG, unit->inv_queue_tail);
}
static void
dmar_qi_ensure(struct dmar_unit *unit, int descr_count)
{
uint32_t head;
int bytes;
DMAR_ASSERT_LOCKED(unit);
bytes = descr_count << DMAR_IQ_DESCR_SZ_SHIFT;
for (;;) {
if (bytes <= unit->inv_queue_avail)
break;
/* refill */
head = dmar_read4(unit, DMAR_IQH_REG);
head &= DMAR_IQH_MASK;
unit->inv_queue_avail = head - unit->inv_queue_tail -
DMAR_IQ_DESCR_SZ;
if (head <= unit->inv_queue_tail)
unit->inv_queue_avail += unit->inv_queue_size;
if (bytes <= unit->inv_queue_avail)
break;
/*
* No space in the queue, do busy wait. Hardware must
* make a progress. But first advance the tail to
* inform the descriptor streamer about entries we
* might have already filled, otherwise they could
* clog the whole queue..
*/
dmar_qi_advance_tail(unit);
unit->inv_queue_full++;
cpu_spinwait();
}
unit->inv_queue_avail -= bytes;
}
static void
dmar_qi_emit(struct dmar_unit *unit, uint64_t data1, uint64_t data2)
{
DMAR_ASSERT_LOCKED(unit);
*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data1;
unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
(uintmax_t)unit->inv_queue_size));
unit->inv_queue_tail &= unit->inv_queue_size - 1;
*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data2;
unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
(uintmax_t)unit->inv_queue_size));
unit->inv_queue_tail &= unit->inv_queue_size - 1;
}
static void
dmar_qi_emit_wait_descr(struct dmar_unit *unit, uint32_t seq, bool intr,
bool memw, bool fence)
{
DMAR_ASSERT_LOCKED(unit);
dmar_qi_emit(unit, DMAR_IQ_DESCR_WAIT_ID |
(intr ? DMAR_IQ_DESCR_WAIT_IF : 0) |
(memw ? DMAR_IQ_DESCR_WAIT_SW : 0) |
(fence ? DMAR_IQ_DESCR_WAIT_FN : 0) |
(memw ? DMAR_IQ_DESCR_WAIT_SD(seq) : 0),
memw ? unit->inv_waitd_seq_hw_phys : 0);
}
static void
dmar_qi_emit_wait_seq(struct dmar_unit *unit, struct dmar_qi_genseq *pseq,
bool emit_wait)
{
struct dmar_qi_genseq gsec;
uint32_t seq;
KASSERT(pseq != NULL, ("wait descriptor with no place for seq"));
DMAR_ASSERT_LOCKED(unit);
if (unit->inv_waitd_seq == 0xffffffff) {
gsec.gen = unit->inv_waitd_gen;
gsec.seq = unit->inv_waitd_seq;
dmar_qi_ensure(unit, 1);
dmar_qi_emit_wait_descr(unit, gsec.seq, false, true, false);
dmar_qi_advance_tail(unit);
while (!dmar_qi_seq_processed(unit, &gsec))
cpu_spinwait();
unit->inv_waitd_gen++;
unit->inv_waitd_seq = 1;
}
seq = unit->inv_waitd_seq++;
pseq->gen = unit->inv_waitd_gen;
pseq->seq = seq;
if (emit_wait) {
dmar_qi_ensure(unit, 1);
dmar_qi_emit_wait_descr(unit, seq, true, true, false);
}
}
static void
dmar_qi_wait_for_seq(struct dmar_unit *unit, const struct dmar_qi_genseq *gseq,
bool nowait)
{
DMAR_ASSERT_LOCKED(unit);
unit->inv_seq_waiters++;
while (!dmar_qi_seq_processed(unit, gseq)) {
if (cold || nowait) {
cpu_spinwait();
} else {
msleep(&unit->inv_seq_waiters, &unit->lock, 0,
"dmarse", hz);
}
}
unit->inv_seq_waiters--;
}
void
dmar_qi_invalidate_locked(struct dmar_domain *domain, dmar_gaddr_t base,
dmar_gaddr_t size, struct dmar_qi_genseq *pseq, bool emit_wait)
{
struct dmar_unit *unit;
dmar_gaddr_t isize;
int am;
unit = domain->dmar;
DMAR_ASSERT_LOCKED(unit);
for (; size > 0; base += isize, size -= isize) {
am = calc_am(unit, base, size, &isize);
dmar_qi_ensure(unit, 1);
dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV |
DMAR_IQ_DESCR_IOTLB_PAGE | DMAR_IQ_DESCR_IOTLB_DW |
DMAR_IQ_DESCR_IOTLB_DR |
DMAR_IQ_DESCR_IOTLB_DID(domain->domain),
base | am);
}
dmar_qi_emit_wait_seq(unit, pseq, emit_wait);
dmar_qi_advance_tail(unit);
}
void
dmar_qi_invalidate_ctx_glob_locked(struct dmar_unit *unit)
{
struct dmar_qi_genseq gseq;
DMAR_ASSERT_LOCKED(unit);
dmar_qi_ensure(unit, 2);
dmar_qi_emit(unit, DMAR_IQ_DESCR_CTX_INV | DMAR_IQ_DESCR_CTX_GLOB, 0);
dmar_qi_emit_wait_seq(unit, &gseq, true);
dmar_qi_advance_tail(unit);
dmar_qi_wait_for_seq(unit, &gseq, false);
}
void
dmar_qi_invalidate_iotlb_glob_locked(struct dmar_unit *unit)
{
struct dmar_qi_genseq gseq;
DMAR_ASSERT_LOCKED(unit);
dmar_qi_ensure(unit, 2);
dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV | DMAR_IQ_DESCR_IOTLB_GLOB |
DMAR_IQ_DESCR_IOTLB_DW | DMAR_IQ_DESCR_IOTLB_DR, 0);
dmar_qi_emit_wait_seq(unit, &gseq, true);
dmar_qi_advance_tail(unit);
dmar_qi_wait_for_seq(unit, &gseq, false);
}
void
dmar_qi_invalidate_iec_glob(struct dmar_unit *unit)
{
struct dmar_qi_genseq gseq;
DMAR_ASSERT_LOCKED(unit);
dmar_qi_ensure(unit, 2);
dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV, 0);
dmar_qi_emit_wait_seq(unit, &gseq, true);
dmar_qi_advance_tail(unit);
dmar_qi_wait_for_seq(unit, &gseq, false);
}
void
dmar_qi_invalidate_iec(struct dmar_unit *unit, u_int start, u_int cnt)
{
struct dmar_qi_genseq gseq;
u_int c, l;
DMAR_ASSERT_LOCKED(unit);
KASSERT(start < unit->irte_cnt && start < start + cnt &&
start + cnt <= unit->irte_cnt,
("inv iec overflow %d %d %d", unit->irte_cnt, start, cnt));
for (; cnt > 0; cnt -= c, start += c) {
l = ffs(start | cnt) - 1;
c = 1 << l;
dmar_qi_ensure(unit, 1);
dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV |
DMAR_IQ_DESCR_IEC_IDX | DMAR_IQ_DESCR_IEC_IIDX(start) |
DMAR_IQ_DESCR_IEC_IM(l), 0);
}
dmar_qi_ensure(unit, 1);
dmar_qi_emit_wait_seq(unit, &gseq, true);
dmar_qi_advance_tail(unit);
/*
* The caller of the function, in particular,
* dmar_ir_program_irte(), may be called from the context
* where the sleeping is forbidden (in fact, the
* intr_table_lock mutex may be held, locked from
* intr_shuffle_irqs()). Wait for the invalidation completion
* using the busy wait.
*
* The impact on the interrupt input setup code is small, the
* expected overhead is comparable with the chipset register
* read. It is more harmful for the parallel DMA operations,
* since we own the dmar unit lock until whole invalidation
* queue is processed, which includes requests possibly issued
* before our request.
*/
dmar_qi_wait_for_seq(unit, &gseq, true);
}
int
dmar_qi_intr(void *arg)
{
struct dmar_unit *unit;
unit = arg;
KASSERT(unit->qi_enabled, ("dmar%d: QI is not enabled", unit->unit));
taskqueue_enqueue(unit->qi_taskqueue, &unit->qi_task);
return (FILTER_HANDLED);
}
static void
dmar_qi_task(void *arg, int pending __unused)
{
struct dmar_unit *unit;
struct dmar_map_entry *entry;
uint32_t ics;
unit = arg;
DMAR_LOCK(unit);
for (;;) {
entry = TAILQ_FIRST(&unit->tlb_flush_entries);
if (entry == NULL)
break;
if (!dmar_qi_seq_processed(unit, &entry->gseq))
break;
TAILQ_REMOVE(&unit->tlb_flush_entries, entry, dmamap_link);
DMAR_UNLOCK(unit);
dmar_domain_free_entry(entry, (entry->flags &
DMAR_MAP_ENTRY_QI_NF) == 0);
DMAR_LOCK(unit);
}
ics = dmar_read4(unit, DMAR_ICS_REG);
if ((ics & DMAR_ICS_IWC) != 0) {
ics = DMAR_ICS_IWC;
dmar_write4(unit, DMAR_ICS_REG, ics);
}
if (unit->inv_seq_waiters > 0)
wakeup(&unit->inv_seq_waiters);
DMAR_UNLOCK(unit);
}
int
dmar_init_qi(struct dmar_unit *unit)
{
uint64_t iqa;
uint32_t ics;
int qi_sz;
if (!DMAR_HAS_QI(unit) || (unit->hw_cap & DMAR_CAP_CM) != 0)
return (0);
unit->qi_enabled = 1;
TUNABLE_INT_FETCH("hw.dmar.qi", &unit->qi_enabled);
if (!unit->qi_enabled)
return (0);
TAILQ_INIT(&unit->tlb_flush_entries);
TASK_INIT(&unit->qi_task, 0, dmar_qi_task, unit);
unit->qi_taskqueue = taskqueue_create_fast("dmarqf", M_WAITOK,
taskqueue_thread_enqueue, &unit->qi_taskqueue);
taskqueue_start_threads(&unit->qi_taskqueue, 1, PI_AV,
"dmar%d qi taskq", unit->unit);
unit->inv_waitd_gen = 0;
unit->inv_waitd_seq = 1;
qi_sz = DMAR_IQA_QS_DEF;
TUNABLE_INT_FETCH("hw.dmar.qi_size", &qi_sz);
if (qi_sz > DMAR_IQA_QS_MAX)
qi_sz = DMAR_IQA_QS_MAX;
unit->inv_queue_size = (1ULL << qi_sz) * PAGE_SIZE;
/* Reserve one descriptor to prevent wraparound. */
unit->inv_queue_avail = unit->inv_queue_size - DMAR_IQ_DESCR_SZ;
/* The invalidation queue reads by DMARs are always coherent. */
unit->inv_queue = kmem_alloc_contig(kernel_arena, unit->inv_queue_size,
M_WAITOK | M_ZERO, 0, dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
unit->inv_waitd_seq_hw_phys = pmap_kextract(
(vm_offset_t)&unit->inv_waitd_seq_hw);
DMAR_LOCK(unit);
dmar_write8(unit, DMAR_IQT_REG, 0);
iqa = pmap_kextract(unit->inv_queue);
iqa |= qi_sz;
dmar_write8(unit, DMAR_IQA_REG, iqa);
dmar_enable_qi(unit);
ics = dmar_read4(unit, DMAR_ICS_REG);
if ((ics & DMAR_ICS_IWC) != 0) {
ics = DMAR_ICS_IWC;
dmar_write4(unit, DMAR_ICS_REG, ics);
}
dmar_enable_qi_intr(unit);
DMAR_UNLOCK(unit);
return (0);
}
void
dmar_fini_qi(struct dmar_unit *unit)
{
struct dmar_qi_genseq gseq;
if (unit->qi_enabled)
return;
taskqueue_drain(unit->qi_taskqueue, &unit->qi_task);
taskqueue_free(unit->qi_taskqueue);
unit->qi_taskqueue = NULL;
DMAR_LOCK(unit);
/* quisce */
dmar_qi_ensure(unit, 1);
dmar_qi_emit_wait_seq(unit, &gseq, true);
dmar_qi_advance_tail(unit);
dmar_qi_wait_for_seq(unit, &gseq, false);
/* only after the quisce, disable queue */
dmar_disable_qi_intr(unit);
dmar_disable_qi(unit);
KASSERT(unit->inv_seq_waiters == 0,
("dmar%d: waiters on disabled queue", unit->unit));
DMAR_UNLOCK(unit);
kmem_free(kernel_arena, unit->inv_queue, unit->inv_queue_size);
unit->inv_queue = 0;
unit->inv_queue_size = 0;
unit->qi_enabled = 0;
}
void
dmar_enable_qi_intr(struct dmar_unit *unit)
{
uint32_t iectl;
DMAR_ASSERT_LOCKED(unit);
KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
iectl = dmar_read4(unit, DMAR_IECTL_REG);
iectl &= ~DMAR_IECTL_IM;
dmar_write4(unit, DMAR_IECTL_REG, iectl);
}
void
dmar_disable_qi_intr(struct dmar_unit *unit)
{
uint32_t iectl;
DMAR_ASSERT_LOCKED(unit);
KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
iectl = dmar_read4(unit, DMAR_IECTL_REG);
dmar_write4(unit, DMAR_IECTL_REG, iectl | DMAR_IECTL_IM);
}