mmio/pio cleanup
v3 cover mmio/pio cleanup
(This is v3 of the series, applies to kvm.git/master:7ff90748)
This is in prep for some more substantial mmio/pio work for iosignalfd, coming later.
[ Changelog:
v3:
*) Addressed feedback from Chris Wright w.r.t. patch 2/3 *) Rebased to kvm.git/master:7ff90748
]
---
Gregory Haskins (3):
kvm: do not register i8254 PIO regions until we are initialized
kvm: cleanup io_device code
kvm: fix potential coalesced_mmio leak on shutdown
arch/x86/kvm/i8254.c | 53 +++++++++++++++++++++++++++++---------------- arch/x86/kvm/i8259.c | 20 ++++++++++++----- arch/x86/kvm/lapic.c | 22 +++++++++++++------ arch/x86/kvm/x86.c | 2 +- virt/kvm/coalesced_mmio.c | 26 ++++++++++++++-------- virt/kvm/ioapic.c | 22 +++++++++++++------ virt/kvm/iodev.h | 29 +++++++++++++++++-------- virt/kvm/kvm_main.c | 2 +- 8 files changed, 117 insertions(+), 59 deletions(-)
Signature · 1 line
Signature
PATCH v3 1/3 kvm: fix potential coalesced_mmio leak on shutdown
It would appear that we are invoking kfree() on the wrong pointer in the destructor for the coalesced_mmio device. This could result in a potential leak during shutdown. This works today because the kvm_io_device is the first element of the private structure, but this could change in the future, so lets clean this up.
---
virt/kvm/coalesced_mmio.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
virt/kvm/coalesced_mmio.c +4 -1
@@ -80,7 +80,10 @@ static void coalesced_mmio_write(struct kvm_io_device *this,static void coalesced_mmio_destructor (struct kvm_io_device *this) { -kfree (this); +struct kvm_coalesced_mmio_dev *dev = + (struct kvm_coalesced_mmio_dev *)this->private; + +kfree (dev); }int kvm_coalesced_mmio_init (struct kvm *kvm)
Re: [KVM PATCH v3 1/3] kvm: fix potential coalesced_mmio leak on shutdown
Quoted 7 lines · * Gregory Haskins ([email protected]) wrote:
It would appear that we are invoking
kfree()on the wrong pointer in the destructor for thecoalesced_mmiodevice. This could result in a potential leak during shutdown. This works today because thekvm_io_deviceis the first element of the private structure, but this could change in the future, so lets clean this up.Signed-off-by Gregory Haskins <[email protected]>
PATCH v3 2/3 kvm: cleanup io_device code
In reply to Gregory HaskinsWe modernize the io_device code so that we use container_of() instead of dev->private, and move the vtable to a separate ops structure (theoretically allows better caching for multiple instances of the same ops structure)
---
arch/x86/kvm/i8254.c | 40 ++++++++++++++++++++++++++++------------ arch/x86/kvm/i8259.c | 20 ++++++++++++++------ arch/x86/kvm/lapic.c | 22 +++++++++++++++------- arch/x86/kvm/x86.c | 2 +- virt/kvm/coalesced_mmio.c | 25 +++++++++++++++---------- virt/kvm/ioapic.c | 22 +++++++++++++++------- virt/kvm/iodev.h | 29 ++++++++++++++++++++--------- virt/kvm/kvm_main.c | 2 +- 8 files changed, 109 insertions(+), 53 deletions(-)
arch/x86/kvm/i8254.c +28 -12
@@ -347,10 +347,20 @@ void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val)mutex_unlock (&kvm->arch.vpit->pit_state.lock); } +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 void pit_ioport_write (struct kvm_io_device *this,gpa_t addr,int len,const void *data) { -struct kvm_pit *pit = (struct kvm_pit *)this->private; +struct kvm_pit *pit =dev_to_pit (this);struct kvm_kpit_state *pit_state = &pit->pit_state;struct kvm *kvm = pit->kvm;int channel, access;
@@ -423,7 +433,7 @@ static void pit_ioport_write(struct kvm_io_device *this,static void pit_ioport_read (struct kvm_io_device *this,gpa_t addr,int len,void *data) { -struct kvm_pit *pit = (struct kvm_pit *)this->private; +struct kvm_pit *pit =dev_to_pit (this);struct kvm_kpit_state *pit_state = &pit->pit_state;struct kvm *kvm = pit->kvm;int ret, count;
@@ -494,7 +504,7 @@ static int pit_in_range(struct kvm_io_device *this, gpa_t addr,static void speaker_ioport_write (struct kvm_io_device *this,gpa_t addr,int len,const void *data) { -struct kvm_pit *pit = (struct kvm_pit *)this->private; +struct kvm_pit *pit =speaker_to_pit (this);struct kvm_kpit_state *pit_state = &pit->pit_state;struct kvm *kvm = pit->kvm;u32 val = *(u32 *) data;
@@ -508,7 +518,7 @@ static void speaker_ioport_write(struct kvm_io_device *this,static void speaker_ioport_read (struct kvm_io_device *this,gpa_t addr,int len,void *data) { -struct kvm_pit *pit = (struct kvm_pit *)this->private; +struct kvm_pit *pit =speaker_to_pit (this);struct kvm_kpit_state *pit_state = &pit->pit_state;struct kvm *kvm = pit->kvm;unsigned int refresh_clock;
@@ -560,6 +570,18 @@ static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) } } +static const struct kvm_io_device_ops pit_dev_ops = { + .read = pit_ioport_read, + .write = pit_ioport_write, + .in_range = pit_in_range, +}; + +static const struct kvm_io_device_ops speaker_dev_ops = { + .read = speaker_ioport_read, + .write = speaker_ioport_write, + .in_range = speaker_in_range, +}; +struct kvm_pit *kvm_create_pit (struct kvm *kvm,u32 flags) {struct kvm_pit *pit;
@@ -580,17 +602,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)spin_lock_init (&pit->pit_state.inject_lock);/* Initialize PIO device */ - pit->dev.read = pit_ioport_read; - pit->dev.write = pit_ioport_write; - pit->dev.in_range = pit_in_range; - pit->dev.private = pit; +kvm_iodevice_init (&pit->dev, &pit_dev_ops);kvm_io_bus_register_dev (&kvm->pio_bus, &pit->dev);if (flags &KVM_PIT_SPEAKER_DUMMY ) { - pit->speaker_dev.read = speaker_ioport_read; - pit->speaker_dev.write = speaker_ioport_write; - pit->speaker_dev.in_range = speaker_in_range; - pit->speaker_dev.private = pit; +kvm_iodevice_init (&pit->speaker_dev, &speaker_dev_ops);kvm_io_bus_register_dev (&kvm->pio_bus, &pit->speaker_dev); }
arch/x86/kvm/i8259.c +14 -6
@@ -444,10 +444,15 @@ static int picdev_in_range(struct kvm_io_device *this, gpa_t addr, } } +static inline struct kvm_pic *to_pic (struct kvm_io_device *dev) +{ + return container_of(dev, struct kvm_pic, dev); +} +static void picdev_write (struct kvm_io_device *this,gpa_t addr,int len,const void *val) { -struct kvm_pic *s = this->private; +struct kvm_pic *s =to_pic (this);unsigned char data = *(unsigned char *)val;if (len !=1 ) {
@@ -474,7 +479,7 @@ static void picdev_write(struct kvm_io_device *this,static void picdev_read (struct kvm_io_device *this,gpa_t addr,int len,void *val) { -struct kvm_pic *s = this->private; +struct kvm_pic *s =to_pic (this);unsigned char data =0 ;if (len !=1 ) {
@@ -516,6 +521,12 @@ static void pic_irq_request(void *opaque, int level) } } +static const struct kvm_io_device_ops picdev_ops = { + .read = picdev_read, + .write = picdev_write, + .in_range = picdev_in_range, +}; +struct kvm_pic *kvm_create_pic (struct kvm *kvm) {struct kvm_pic *s;
@@ -534,10 +545,7 @@ struct kvm_pic *kvm_create_pic(struct kvm *kvm)/* * Initialize PIO device */ - s->dev.read = picdev_read; - s->dev.write = picdev_write; - s->dev.in_range = picdev_in_range; - s->dev.private = s; +kvm_iodevice_init (&s->dev, &picdev_ops);kvm_io_bus_register_dev (&kvm->pio_bus, &s->dev);return s; }
arch/x86/kvm/lapic.c +15 -7
@@ -522,10 +522,15 @@ static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset)return val; } +static inline struct kvm_lapic *to_lapic (struct kvm_io_device *dev) +{ + return container_of(dev, struct kvm_lapic, dev); +} +static void apic_mmio_read (struct kvm_io_device *this,gpa_t address,int len,void *data) { -struct kvm_lapic *apic = (struct kvm_lapic *)this->private; +struct kvm_lapic *apic =to_lapic (this);unsigned int offset = address - apic->base_address;unsigned char alignment = offset &0xf ;u32 result;
@@ -606,7 +611,7 @@ static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val)static void apic_mmio_write (struct kvm_io_device *this,gpa_t address,int len,const void *data) { -struct kvm_lapic *apic = (struct kvm_lapic *)this->private; +struct kvm_lapic *apic =to_lapic (this);unsigned int offset = address - apic->base_address;unsigned char alignment = offset &0xf ;u32 val;
@@ -723,7 +728,7 @@ static void apic_mmio_write(struct kvm_io_device *this,static int apic_mmio_range (struct kvm_io_device *this,gpa_t addr,int len,int size) { -struct kvm_lapic *apic = (struct kvm_lapic *)this->private; +struct kvm_lapic *apic =to_lapic (this);int ret =0 ;
@@ -917,6 +922,12 @@ static struct kvm_timer_ops lapic_timer_ops = { .is_periodic = lapic_is_periodic, }; +static const struct kvm_io_device_ops apic_mmio_ops = { + .read = apic_mmio_read, + .write = apic_mmio_write, + .in_range = apic_mmio_range, +}; +int kvm_create_lapic (struct kvm_vcpu *vcpu) {struct kvm_lapic *apic;
@@ -951,10 +962,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu) vcpu->arch.apic_base =APIC_DEFAULT_PHYS_BASE ;kvm_lapic_reset (vcpu); - apic->dev.read = apic_mmio_read; - apic->dev.write = apic_mmio_write; - apic->dev.in_range = apic_mmio_range; - apic->dev.private = apic; +kvm_iodevice_init (&apic->dev, &apic_mmio_ops);return 0 ; nomem_free_apic:
arch/x86/kvm/x86.c +1 -1
@@ -2227,7 +2227,7 @@ static struct kvm_io_device *vcpu_find_pervcpu_dev(struct kvm_vcpu *vcpu,if (vcpu->arch.apic) { dev = &vcpu->arch.apic->dev; -if (dev->in_range (dev, addr, len, is_write)) +if (kvm_iodevice_in_range (dev, addr, len, is_write))return dev; }return NULL ;
virt/kvm/coalesced_mmio.c +15 -10
@@ -14,11 +14,15 @@#include "coalesced_mmio.h" +static inline struct kvm_coalesced_mmio_dev *to_mmio (struct kvm_io_device *dev) +{ + return container_of(dev, struct kvm_coalesced_mmio_dev, dev); +} +static int coalesced_mmio_in_range (struct kvm_io_device *this,gpa_t addr,int len,int is_write) { -struct kvm_coalesced_mmio_dev *dev = - (struct kvm_coalesced_mmio_dev *)this->private; +struct kvm_coalesced_mmio_dev *dev =to_mmio (this);struct kvm_coalesced_mmio_zone *zone;int next;int i;
@@ -63,8 +67,7 @@ static int coalesced_mmio_in_range(struct kvm_io_device *this,static void coalesced_mmio_write (struct kvm_io_device *this,gpa_t addr,int len,const void *val) { -struct kvm_coalesced_mmio_dev *dev = - (struct kvm_coalesced_mmio_dev *)this->private; +struct kvm_coalesced_mmio_dev *dev =to_mmio (this);struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring;/* kvm->lock must be taken by caller before call to in_range()*/
@@ -80,12 +83,17 @@ static void coalesced_mmio_write(struct kvm_io_device *this,static void coalesced_mmio_destructor (struct kvm_io_device *this) { -struct kvm_coalesced_mmio_dev *dev = - (struct kvm_coalesced_mmio_dev *)this->private; +struct kvm_coalesced_mmio_dev *dev =to_mmio (this);kfree (dev); } +static const struct kvm_io_device_ops coalesced_mmio_ops = { + .write = coalesced_mmio_write, + .in_range = coalesced_mmio_in_range, + .destructor = coalesced_mmio_destructor, +}; +int kvm_coalesced_mmio_init (struct kvm *kvm) {struct kvm_coalesced_mmio_dev *dev;
@@ -93,10 +101,7 @@ int kvm_coalesced_mmio_init(struct kvm *kvm) dev =kzalloc (sizeof (struct kvm_coalesced_mmio_dev ),GFP_KERNEL );if (!dev)return -ENOMEM ; - dev->dev.write = coalesced_mmio_write; - dev->dev.in_range = coalesced_mmio_in_range; - dev->dev.destructor = coalesced_mmio_destructor; - dev->dev.private = dev; +kvm_iodevice_init (&dev->dev, &coalesced_mmio_ops); dev->kvm = kvm; kvm->coalesced_mmio_dev = dev;kvm_io_bus_register_dev (&kvm->mmio_bus, &dev->dev);
virt/kvm/ioapic.c +15 -7
@@ -220,10 +220,15 @@ void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)__kvm_ioapic_update_eoi (ioapic, i, trigger_mode); } +static inline struct kvm_ioapic *to_ioapic (struct kvm_io_device *dev) +{ + return container_of(dev, struct kvm_ioapic, dev); +} +static int ioapic_in_range (struct kvm_io_device *this,gpa_t addr,int len,int is_write) { -struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private; +struct kvm_ioapic *ioapic =to_ioapic (this);return ((addr >= ioapic->base_address && (addr < ioapic->base_address +IOAPIC_MEM_LENGTH )));
@@ -232,7 +237,7 @@ static int ioapic_in_range(struct kvm_io_device *this, gpa_t addr,static void ioapic_mmio_read (struct kvm_io_device *this,gpa_t addr,int len,void *val) { -struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private; +struct kvm_ioapic *ioapic =to_ioapic (this);u32 result;ioapic_debug ("addr %lx\n" , (unsigned long )addr);
@@ -269,7 +274,7 @@ static void ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,static void ioapic_mmio_write (struct kvm_io_device *this,gpa_t addr,int len,const void *val) { -struct kvm_ioapic *ioapic = (struct kvm_ioapic *)this->private; +struct kvm_ioapic *ioapic =to_ioapic (this);u32 data; ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
@@ -314,6 +319,12 @@ void kvm_ioapic_reset(struct kvm_ioapic *ioapic) ioapic->id =0 ; } +static const struct kvm_io_device_ops ioapic_mmio_ops = { + .read = ioapic_mmio_read, + .write = ioapic_mmio_write, + .in_range = ioapic_in_range, +}; +int kvm_ioapic_init (struct kvm *kvm) {struct kvm_ioapic *ioapic;
@@ -323,10 +334,7 @@ int kvm_ioapic_init(struct kvm *kvm)return -ENOMEM ; kvm->arch.vioapic = ioapic;kvm_ioapic_reset (ioapic); - ioapic->dev.read = ioapic_mmio_read; - ioapic->dev.write = ioapic_mmio_write; - ioapic->dev.in_range = ioapic_in_range; - ioapic->dev.private = ioapic; +kvm_iodevice_init (&ioapic->dev, &ioapic_mmio_ops); ioapic->kvm = kvm;kvm_io_bus_register_dev (&kvm->mmio_bus, &ioapic->dev);return 0 ;
virt/kvm/iodev.h +20 -9
@@ -18,7 +18,9 @@#include <linux/kvm_types.h> -struct kvm_io_device { +struct kvm_io_device ; + +struct kvm_io_device_ops { void (*read)(struct kvm_io_device *this, gpa_t addr, int len,
@@ -30,16 +32,25 @@ struct kvm_io_device {int (*in_range)(struct kvm_io_device *this,gpa_t addr,int len,int is_write);void (*destructor)(struct kvm_io_device *this); +}; + -void *private; +struct kvm_io_device { +const struct kvm_io_device_ops *ops; }; +static inline void kvm_iodevice_init (struct kvm_io_device *dev, +const struct kvm_io_device_ops *ops) +{ + dev->ops = ops; +} +static inline void kvm_iodevice_read (struct kvm_io_device *dev,gpa_t addr,int len,void *val) { - dev->read (dev, addr, len, val); + dev->ops->read (dev, addr, len, val); } static inline void kvm_iodevice_write(struct kvm_io_device *dev,
@@ -47,19 +58,19 @@ static inline void kvm_iodevice_write(struct kvm_io_device *dev,int len, const void *val) { - dev->write(dev, addr, len, val); + dev->ops->write(dev, addr, len, val); } -static inline int kvm_iodevice_inrange (struct kvm_io_device *dev, -gpa_t addr,int len,int is_write) +static inline int kvm_iodevice_in_range (struct kvm_io_device *dev, +gpa_t addr,int len,int is_write) { -return dev->in_range (dev, addr, len, is_write); +return dev->ops->in_range (dev, addr, len, is_write); }static inline void kvm_iodevice_destructor (struct kvm_io_device *dev) { -if (dev->destructor) - dev->destructor (dev); +if (dev->ops->destructor) + dev->ops->destructor (dev); }#endif /* __KVM_IODEV_H__ */
virt/kvm/kvm_main.c +1 -1
@@ -2450,7 +2450,7 @@ struct kvm_io_device *kvm_io_bus_find_dev(struct kvm_io_bus *bus,for (i =0 ; i < bus->dev_count; i++) {struct kvm_io_device *pos = bus->devs[i]; -if (pos->in_range (pos, addr, len, is_write)) +if (kvm_iodevice_in_range (pos, addr, len, is_write))return pos; }
Re: [KVM PATCH v3 2/3] kvm: cleanup io_device code
Quoted 6 lines · * Gregory Haskins ([email protected]) wrote:
We modernize the
io_devicecode so that we usecontainer_of()instead ofdev->private, and move the vtable to a separate ops structure (theoretically allows better caching for multiple instances of the same ops structure)Signed-off-by Gregory Haskins <[email protected]>
PATCH v3 3/3 kvm: do not register i8254 PIO regions until we are initialized
In reply to Gregory HaskinsWe currently publish the i8254 resources to the pio_bus before the devices are fully initialized. Since we hold the pit_lock, its probably not a real issue. But lets clean this up anyway.
---
arch/x86/kvm/i8254.c | 17 ++++++++--------- 1 files changed, 8 insertions(+), 9 deletions(-)
arch/x86/kvm/i8254.c +8 -9
@@ -601,15 +601,6 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags)mutex_lock (&pit->pit_state.lock);spin_lock_init (&pit->pit_state.inject_lock); -/* Initialize PIO device */ -kvm_iodevice_init (&pit->dev, &pit_dev_ops); -kvm_io_bus_register_dev (&kvm->pio_bus, &pit->dev); - -if (flags &KVM_PIT_SPEAKER_DUMMY ) { -kvm_iodevice_init (&pit->speaker_dev, &speaker_dev_ops); -kvm_io_bus_register_dev (&kvm->pio_bus, &pit->speaker_dev); - } - kvm->arch.vpit = pit; pit->kvm = kvm;
@@ -628,6 +619,14 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) pit->mask_notifier.func = pit_mask_notifer;kvm_register_irq_mask_notifier (kvm,0 , &pit->mask_notifier); +kvm_iodevice_init (&pit->dev, &pit_dev_ops); +kvm_io_bus_register_dev (&kvm->pio_bus, &pit->dev); + +if (flags &KVM_PIT_SPEAKER_DUMMY ) { +kvm_iodevice_init (&pit->speaker_dev, &speaker_dev_ops); +kvm_io_bus_register_dev (&kvm->pio_bus, &pit->speaker_dev); + } +return pit; }
Re: [KVM PATCH v3 3/3] kvm: do not register i8254 PIO regions until we are initialized
Quoted 6 lines · * Gregory Haskins ([email protected]) wrote:
We currently publish the i8254 resources to the
pio_busbefore the devices are fully initialized. Since we hold thepit_lock, its probably not a real issue. But lets clean this up anyway.Found-by Avi Kivity <[email protected]>Signed-off-by Gregory Haskins <[email protected]>
Quoted 5 lines · Gregory Haskins
(This is v3 of the series, applies to kvm.git/master:7ff90748)
This is in prep for some more substantial mmio/pio work for iosignalfd, coming later.
Quoted 8 lines
[ Changelog:
v3:
*) Addressed feedback from Chris Wright w.r.t. patch 2/3 *) Rebased to kvm.git/master:7ff90748]
All in, thanks.
Signature · 1 line
error compiling committee.c: too many arguments to function