kernel_optimize_test/arch/x86/kvm/i8254.c

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/*
* 8253/8254 interval timer emulation
*
* Copyright (c) 2003-2004 Fabrice Bellard
* Copyright (c) 2006 Intel Corporation
* Copyright (c) 2007 Keir Fraser, XenSource Inc
* Copyright (c) 2008 Intel Corporation
* Copyright 2009 Red Hat, Inc. and/or its affiliates.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* Authors:
* Sheng Yang <sheng.yang@intel.com>
* Based on QEMU and Xen.
*/
#define pr_fmt(fmt) "pit: " fmt
#include <linux/kvm_host.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include "ioapic.h"
#include "irq.h"
#include "i8254.h"
#include "x86.h"
#ifndef CONFIG_X86_64
#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
#else
#define mod_64(x, y) ((x) % (y))
#endif
#define RW_STATE_LSB 1
#define RW_STATE_MSB 2
#define RW_STATE_WORD0 3
#define RW_STATE_WORD1 4
static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val)
{
struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
switch (c->mode) {
default:
case 0:
case 4:
/* XXX: just disable/enable counting */
break;
case 1:
case 2:
case 3:
case 5:
/* Restart counting on rising edge. */
if (c->gate < val)
c->count_load_time = ktime_get();
break;
}
c->gate = val;
}
static int pit_get_gate(struct kvm_pit *pit, int channel)
{
return pit->pit_state.channels[channel].gate;
}
static s64 __kpit_elapsed(struct kvm_pit *pit)
{
s64 elapsed;
ktime_t remaining;
struct kvm_kpit_state *ps = &pit->pit_state;
if (!ps->period)
return 0;
/*
* The Counter does not stop when it reaches zero. In
* Modes 0, 1, 4, and 5 the Counter ``wraps around'' to
* the highest count, either FFFF hex for binary counting
* or 9999 for BCD counting, and continues counting.
* Modes 2 and 3 are periodic; the Counter reloads
* itself with the initial count and continues counting
* from there.
*/
remaining = hrtimer_get_remaining(&ps->timer);
elapsed = ps->period - ktime_to_ns(remaining);
return elapsed;
}
static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c,
int channel)
{
if (channel == 0)
return __kpit_elapsed(pit);
return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
}
static int pit_get_count(struct kvm_pit *pit, int channel)
{
struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
s64 d, t;
int counter;
t = kpit_elapsed(pit, c, channel);
d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
case 0:
case 1:
case 4:
case 5:
counter = (c->count - d) & 0xffff;
break;
case 3:
/* XXX: may be incorrect for odd counts */
counter = c->count - (mod_64((2 * d), c->count));
break;
default:
counter = c->count - mod_64(d, c->count);
break;
}
return counter;
}
static int pit_get_out(struct kvm_pit *pit, int channel)
{
struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
s64 d, t;
int out;
t = kpit_elapsed(pit, c, channel);
d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC);
switch (c->mode) {
default:
case 0:
out = (d >= c->count);
break;
case 1:
out = (d < c->count);
break;
case 2:
out = ((mod_64(d, c->count) == 0) && (d != 0));
break;
case 3:
out = (mod_64(d, c->count) < ((c->count + 1) >> 1));
break;
case 4:
case 5:
out = (d == c->count);
break;
}
return out;
}
static void pit_latch_count(struct kvm_pit *pit, int channel)
{
struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
if (!c->count_latched) {
c->latched_count = pit_get_count(pit, channel);
c->count_latched = c->rw_mode;
}
}
static void pit_latch_status(struct kvm_pit *pit, int channel)
{
struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel];
if (!c->status_latched) {
/* TODO: Return NULL COUNT (bit 6). */
c->status = ((pit_get_out(pit, channel) << 7) |
(c->rw_mode << 4) |
(c->mode << 1) |
c->bcd);
c->status_latched = 1;
}
}
static inline struct kvm_pit *pit_state_to_pit(struct kvm_kpit_state *ps)
{
return container_of(ps, struct kvm_pit, pit_state);
}
static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian)
{
struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state,
irq_ack_notifier);
struct kvm_pit *pit = pit_state_to_pit(ps);
atomic_set(&ps->irq_ack, 1);
/* irq_ack should be set before pending is read. Order accesses with
* inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work.
*/
smp_mb();
if (atomic_dec_if_positive(&ps->pending) > 0)
kthread_queue_work(pit->worker, &pit->expired);
}
void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
{
struct kvm_pit *pit = vcpu->kvm->arch.vpit;
struct hrtimer *timer;
if (!kvm_vcpu_is_bsp(vcpu) || !pit)
return;
timer = &pit->pit_state.timer;
mutex_lock(&pit->pit_state.lock);
if (hrtimer_cancel(timer))
hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
mutex_unlock(&pit->pit_state.lock);
}
static void destroy_pit_timer(struct kvm_pit *pit)
{
hrtimer_cancel(&pit->pit_state.timer);
kthread: kthread worker API cleanup A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-12 04:55:20 +08:00
kthread_flush_work(&pit->expired);
}
static void pit_do_work(struct kthread_work *work)
{
struct kvm_pit *pit = container_of(work, struct kvm_pit, expired);
struct kvm *kvm = pit->kvm;
struct kvm_vcpu *vcpu;
int i;
struct kvm_kpit_state *ps = &pit->pit_state;
if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0))
return;
kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false);
kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false);
/*
* Provides NMI watchdog support via Virtual Wire mode.
* The route is: PIT -> LVT0 in NMI mode.
*
* Note: Our Virtual Wire implementation does not follow
* the MP specification. We propagate a PIT interrupt to all
* VCPUs and only when LVT0 is in NMI mode. The interrupt can
* also be simultaneously delivered through PIC and IOAPIC.
*/
if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0)
kvm_for_each_vcpu(i, vcpu, kvm)
kvm_apic_nmi_wd_deliver(vcpu);
}
static enum hrtimer_restart pit_timer_fn(struct hrtimer *data)
{
struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer);
struct kvm_pit *pt = pit_state_to_pit(ps);
if (atomic_read(&ps->reinject))
atomic_inc(&ps->pending);
kthread_queue_work(pt->worker, &pt->expired);
if (ps->is_periodic) {
hrtimer_add_expires_ns(&ps->timer, ps->period);
return HRTIMER_RESTART;
} else
return HRTIMER_NORESTART;
}
static inline void kvm_pit_reset_reinject(struct kvm_pit *pit)
{
atomic_set(&pit->pit_state.pending, 0);
atomic_set(&pit->pit_state.irq_ack, 1);
}
void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject)
{
struct kvm_kpit_state *ps = &pit->pit_state;
struct kvm *kvm = pit->kvm;
if (atomic_read(&ps->reinject) == reinject)
return;
if (reinject) {
/* The initial state is preserved while ps->reinject == 0. */
kvm_pit_reset_reinject(pit);
kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
} else {
kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier);
kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier);
}
atomic_set(&ps->reinject, reinject);
}
static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period)
{
struct kvm_kpit_state *ps = &pit->pit_state;
struct kvm *kvm = pit->kvm;
s64 interval;
if (!ioapic_in_kernel(kvm) ||
ps->flags & KVM_PIT_FLAGS_HPET_LEGACY)
return;
interval = mul_u64_u32_div(val, NSEC_PER_SEC, KVM_PIT_FREQ);
pr_debug("create pit timer, interval is %llu nsec\n", interval);
/* TODO The new value only affected after the retriggered */
hrtimer_cancel(&ps->timer);
kthread: kthread worker API cleanup A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-12 04:55:20 +08:00
kthread_flush_work(&pit->expired);
ps->period = interval;
ps->is_periodic = is_period;
kvm_pit_reset_reinject(pit);
/*
* Do not allow the guest to program periodic timers with small
* interval, since the hrtimers are not throttled by the host
* scheduler.
*/
if (ps->is_periodic) {
s64 min_period = min_timer_period_us * 1000LL;
if (ps->period < min_period) {
pr_info_ratelimited(
"kvm: requested %lld ns "
"i8254 timer period limited to %lld ns\n",
ps->period, min_period);
ps->period = min_period;
}
}
hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval),
HRTIMER_MODE_ABS);
}
static void pit_load_count(struct kvm_pit *pit, int channel, u32 val)
{
struct kvm_kpit_state *ps = &pit->pit_state;
pr_debug("load_count val is %d, channel is %d\n", val, channel);
/*
* The largest possible initial count is 0; this is equivalent
* to 216 for binary counting and 104 for BCD counting.
*/
if (val == 0)
val = 0x10000;
ps->channels[channel].count = val;
if (channel != 0) {
ps->channels[channel].count_load_time = ktime_get();
return;
}
/* Two types of timer
* mode 1 is one shot, mode 2 is period, otherwise del timer */
switch (ps->channels[0].mode) {
case 0:
case 1:
/* FIXME: enhance mode 4 precision */
case 4:
create_pit_timer(pit, val, 0);
break;
case 2:
case 3:
create_pit_timer(pit, val, 1);
break;
default:
destroy_pit_timer(pit);
}
}
void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val,
int hpet_legacy_start)
{
u8 saved_mode;
WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock));
if (hpet_legacy_start) {
/* save existing mode for later reenablement */
WARN_ON(channel != 0);
saved_mode = pit->pit_state.channels[0].mode;
pit->pit_state.channels[0].mode = 0xff; /* disable timer */
pit_load_count(pit, channel, val);
pit->pit_state.channels[0].mode = saved_mode;
} else {
pit_load_count(pit, channel, val);
}
}
static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev)
{
return container_of(dev, struct kvm_pit, dev);
}
static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev)
{
return container_of(dev, struct kvm_pit, speaker_dev);
}
static inline int pit_in_range(gpa_t addr)
{
return ((addr >= KVM_PIT_BASE_ADDRESS) &&
(addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH));
}
static int pit_ioport_write(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, const void *data)
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
int channel, access;
struct kvm_kpit_channel_state *s;
u32 val = *(u32 *) data;
if (!pit_in_range(addr))
return -EOPNOTSUPP;
val &= 0xff;
addr &= KVM_PIT_CHANNEL_MASK;
mutex_lock(&pit_state->lock);
if (val != 0)
pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n",
(unsigned int)addr, len, val);
if (addr == 3) {
channel = val >> 6;
if (channel == 3) {
/* Read-Back Command. */
for (channel = 0; channel < 3; channel++) {
s = &pit_state->channels[channel];
if (val & (2 << channel)) {
if (!(val & 0x20))
pit_latch_count(pit, channel);
if (!(val & 0x10))
pit_latch_status(pit, channel);
}
}
} else {
/* Select Counter <channel>. */
s = &pit_state->channels[channel];
access = (val >> 4) & KVM_PIT_CHANNEL_MASK;
if (access == 0) {
pit_latch_count(pit, channel);
} else {
s->rw_mode = access;
s->read_state = access;
s->write_state = access;
s->mode = (val >> 1) & 7;
if (s->mode > 5)
s->mode -= 4;
s->bcd = val & 1;
}
}
} else {
/* Write Count. */
s = &pit_state->channels[addr];
switch (s->write_state) {
default:
case RW_STATE_LSB:
pit_load_count(pit, addr, val);
break;
case RW_STATE_MSB:
pit_load_count(pit, addr, val << 8);
break;
case RW_STATE_WORD0:
s->write_latch = val;
s->write_state = RW_STATE_WORD1;
break;
case RW_STATE_WORD1:
pit_load_count(pit, addr, s->write_latch | (val << 8));
s->write_state = RW_STATE_WORD0;
break;
}
}
mutex_unlock(&pit_state->lock);
return 0;
}
static int pit_ioport_read(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, void *data)
{
struct kvm_pit *pit = dev_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
int ret, count;
struct kvm_kpit_channel_state *s;
if (!pit_in_range(addr))
return -EOPNOTSUPP;
addr &= KVM_PIT_CHANNEL_MASK;
if (addr == 3)
return 0;
s = &pit_state->channels[addr];
mutex_lock(&pit_state->lock);
if (s->status_latched) {
s->status_latched = 0;
ret = s->status;
} else if (s->count_latched) {
switch (s->count_latched) {
default:
case RW_STATE_LSB:
ret = s->latched_count & 0xff;
s->count_latched = 0;
break;
case RW_STATE_MSB:
ret = s->latched_count >> 8;
s->count_latched = 0;
break;
case RW_STATE_WORD0:
ret = s->latched_count & 0xff;
s->count_latched = RW_STATE_MSB;
break;
}
} else {
switch (s->read_state) {
default:
case RW_STATE_LSB:
count = pit_get_count(pit, addr);
ret = count & 0xff;
break;
case RW_STATE_MSB:
count = pit_get_count(pit, addr);
ret = (count >> 8) & 0xff;
break;
case RW_STATE_WORD0:
count = pit_get_count(pit, addr);
ret = count & 0xff;
s->read_state = RW_STATE_WORD1;
break;
case RW_STATE_WORD1:
count = pit_get_count(pit, addr);
ret = (count >> 8) & 0xff;
s->read_state = RW_STATE_WORD0;
break;
}
}
if (len > sizeof(ret))
len = sizeof(ret);
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
return 0;
}
static int speaker_ioport_write(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, const void *data)
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
u32 val = *(u32 *) data;
if (addr != KVM_SPEAKER_BASE_ADDRESS)
return -EOPNOTSUPP;
mutex_lock(&pit_state->lock);
pit_state->speaker_data_on = (val >> 1) & 1;
pit_set_gate(pit, 2, val & 1);
mutex_unlock(&pit_state->lock);
return 0;
}
static int speaker_ioport_read(struct kvm_vcpu *vcpu,
struct kvm_io_device *this,
gpa_t addr, int len, void *data)
{
struct kvm_pit *pit = speaker_to_pit(this);
struct kvm_kpit_state *pit_state = &pit->pit_state;
unsigned int refresh_clock;
int ret;
if (addr != KVM_SPEAKER_BASE_ADDRESS)
return -EOPNOTSUPP;
/* Refresh clock toggles at about 15us. We approximate as 2^14ns. */
refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1;
mutex_lock(&pit_state->lock);
ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(pit, 2) |
(pit_get_out(pit, 2) << 5) | (refresh_clock << 4));
if (len > sizeof(ret))
len = sizeof(ret);
memcpy(data, (char *)&ret, len);
mutex_unlock(&pit_state->lock);
return 0;
}
static void kvm_pit_reset(struct kvm_pit *pit)
{
int i;
struct kvm_kpit_channel_state *c;
pit->pit_state.flags = 0;
for (i = 0; i < 3; i++) {
c = &pit->pit_state.channels[i];
c->mode = 0xff;
c->gate = (i != 2);
pit_load_count(pit, i, 0);
}
kvm_pit_reset_reinject(pit);
}
static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask)
{
struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier);
if (!mask)
kvm_pit_reset_reinject(pit);
}
static const struct kvm_io_device_ops pit_dev_ops = {
.read = pit_ioport_read,
.write = pit_ioport_write,
};
static const struct kvm_io_device_ops speaker_dev_ops = {
.read = speaker_ioport_read,
.write = speaker_ioport_write,
};
struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)
{
struct kvm_pit *pit;
struct kvm_kpit_state *pit_state;
struct pid *pid;
pid_t pid_nr;
int ret;
pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL_ACCOUNT);
if (!pit)
return NULL;
pit->irq_source_id = kvm_request_irq_source_id(kvm);
if (pit->irq_source_id < 0)
goto fail_request;
mutex_init(&pit->pit_state.lock);
pid = get_pid(task_tgid(current));
pid_nr = pid_vnr(pid);
put_pid(pid);
pit->worker = kthread_create_worker(0, "kvm-pit/%d", pid_nr);
if (IS_ERR(pit->worker))
goto fail_kthread;
kthread: kthread worker API cleanup A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-12 04:55:20 +08:00
kthread_init_work(&pit->expired, pit_do_work);
pit->kvm = kvm;
pit_state = &pit->pit_state;
hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
pit_state->timer.function = pit_timer_fn;
pit_state->irq_ack_notifier.gsi = 0;
pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq;
pit->mask_notifier.func = pit_mask_notifer;
kvm_pit_reset(pit);
kvm_pit_set_reinject(pit, true);
mutex_lock(&kvm->slots_lock);
kvm_iodevice_init(&pit->dev, &pit_dev_ops);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS,
KVM_PIT_MEM_LENGTH, &pit->dev);
if (ret < 0)
goto fail_register_pit;
if (flags & KVM_PIT_SPEAKER_DUMMY) {
kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops);
ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS,
KVM_SPEAKER_BASE_ADDRESS, 4,
&pit->speaker_dev);
if (ret < 0)
goto fail_register_speaker;
}
mutex_unlock(&kvm->slots_lock);
return pit;
fail_register_speaker:
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
fail_register_pit:
mutex_unlock(&kvm->slots_lock);
kvm_pit_set_reinject(pit, false);
kthread_destroy_worker(pit->worker);
fail_kthread:
kvm_free_irq_source_id(kvm, pit->irq_source_id);
fail_request:
kfree(pit);
return NULL;
}
void kvm_free_pit(struct kvm *kvm)
{
struct kvm_pit *pit = kvm->arch.vpit;
if (pit) {
mutex_lock(&kvm->slots_lock);
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev);
kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev);
mutex_unlock(&kvm->slots_lock);
kvm_pit_set_reinject(pit, false);
hrtimer_cancel(&pit->pit_state.timer);
kthread_destroy_worker(pit->worker);
kvm_free_irq_source_id(kvm, pit->irq_source_id);
kfree(pit);
}
}