Re: [PATCH kvmtool 19/21] Remove ioport specific routines

[Andre Przywara <andre.przywara@arm.com>]

On Wed, 17 Feb 2021 16:11:51 +0000
Alexandru Elisei <alexandru.elisei@arm.com> wrote:

> Hi Andre,
> 
> On 2/17/21 3:49 PM, Alexandru Elisei wrote:
> > Hi Andre,
> >
> > On 12/10/20 2:29 PM, Andre Przywara wrote:  
> >> Now that all users of the dedicated ioport trap handler interface are
> >> gone, we can retire the code associated with it.
> >>
> >> This removes ioport.c and ioport.h, along with removing prototypes from
> >> other header files.
> >>
> >> This also transfers the responsibility for port I/O trap handling
> >> entirely into the new routine in mmio.c.
> >>
> >> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> >> ---
> >>  Makefile             |   1 -
> >>  include/kvm/ioport.h |  20 -----
> >>  include/kvm/kvm.h    |   2 -
> >>  ioport.c             | 173 -------------------------------------------
> >>  mmio.c               |   2 +-
> >>  5 files changed, 1 insertion(+), 197 deletions(-)
> >>  delete mode 100644 ioport.c
> >>
> >> diff --git a/Makefile b/Makefile
> >> index 35bb1182..94ff5da6 100644
> >> --- a/Makefile
> >> +++ b/Makefile
> >> @@ -56,7 +56,6 @@ OBJS	+= framebuffer.o
> >>  OBJS	+= guest_compat.o
> >>  OBJS	+= hw/rtc.o
> >>  OBJS	+= hw/serial.o
> >> -OBJS	+= ioport.o
> >>  OBJS	+= irq.o
> >>  OBJS	+= kvm-cpu.o
> >>  OBJS	+= kvm.o
> >> diff --git a/include/kvm/ioport.h b/include/kvm/ioport.h
> >> index a61038e2..38636553 100644
> >> --- a/include/kvm/ioport.h
> >> +++ b/include/kvm/ioport.h
> >> @@ -17,28 +17,8 @@
> >>  
> >>  struct kvm;  
> > Looks to me like the above forward declaration can be removed; same for all the
> > includes except linux/byteorder.h, needed for the lexx_to_cpu/cpu_to_lexx
> > functions, and linux/types.h for the uxx typedefs. Otherwise looks good.  
> 
> Actually, ignore the part about removing the includes, it opens a new can of worms
> - byteorder.h doesn't include compiler.h where __always_inline is defined, and
> various files where struct kvm_cpu is used don't include kvm-cpu.h (like pci.c,
> hw/serial.c, etc). The header removal is not trivial and I think it should be part
> of another cleanup patch.

Well, it looks like I can remove some obvious headers like for fdt and
rbtree. Will do that.

Cheers,
Andre

> >
> > Thanks,
> >
> > Alex
> >  
> >>  
> >> -struct ioport {
> >> -	struct rb_int_node		node;
> >> -	struct ioport_operations	*ops;
> >> -	void				*priv;
> >> -	struct device_header		dev_hdr;
> >> -	u32				refcount;
> >> -	bool				remove;
> >> -};
> >> -
> >> -struct ioport_operations {
> >> -	bool (*io_in)(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size);
> >> -	bool (*io_out)(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size);
> >> -};
> >> -
> >>  void ioport__map_irq(u8 *irq);
> >>  
> >> -int __must_check ioport__register(struct kvm *kvm, u16 port, struct ioport_operations *ops,
> >> -				  int count, void *param);
> >> -int ioport__unregister(struct kvm *kvm, u16 port);
> >> -int ioport__init(struct kvm *kvm);
> >> -int ioport__exit(struct kvm *kvm);
> >> -
> >>  static inline u8 ioport__read8(u8 *data)
> >>  {
> >>  	return *data;
> >> diff --git a/include/kvm/kvm.h b/include/kvm/kvm.h
> >> index 14f9d58b..e70f8ef6 100644
> >> --- a/include/kvm/kvm.h
> >> +++ b/include/kvm/kvm.h
> >> @@ -119,8 +119,6 @@ void kvm__irq_line(struct kvm *kvm, int irq, int level);
> >>  void kvm__irq_trigger(struct kvm *kvm, int irq);
> >>  bool kvm__emulate_io(struct kvm_cpu *vcpu, u16 port, void *data, int direction, int size, u32 count);
> >>  bool kvm__emulate_mmio(struct kvm_cpu *vcpu, u64 phys_addr, u8 *data, u32 len, u8 is_write);
> >> -bool kvm__emulate_pio(struct kvm_cpu *vcpu, u16 port, void *data,
> >> -		      int direction, int size, u32 count);
> >>  int kvm__destroy_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr);
> >>  int kvm__register_mem(struct kvm *kvm, u64 guest_phys, u64 size, void *userspace_addr,
> >>  		      enum kvm_mem_type type);
> >> diff --git a/ioport.c b/ioport.c
> >> deleted file mode 100644
> >> index 204d8103..00000000
> >> --- a/ioport.c
> >> +++ /dev/null
> >> @@ -1,173 +0,0 @@
> >> -#include "kvm/ioport.h"
> >> -
> >> -#include "kvm/kvm.h"
> >> -#include "kvm/util.h"
> >> -#include "kvm/rbtree-interval.h"
> >> -#include "kvm/mutex.h"
> >> -
> >> -#include <linux/kvm.h>	/* for KVM_EXIT_* */
> >> -#include <linux/types.h>
> >> -
> >> -#include <stdbool.h>
> >> -#include <limits.h>
> >> -#include <stdlib.h>
> >> -#include <stdio.h>
> >> -
> >> -#define ioport_node(n) rb_entry(n, struct ioport, node)
> >> -
> >> -static DEFINE_MUTEX(ioport_lock);
> >> -
> >> -static struct rb_root		ioport_tree = RB_ROOT;
> >> -
> >> -static struct ioport *ioport_search(struct rb_root *root, u64 addr)
> >> -{
> >> -	struct rb_int_node *node;
> >> -
> >> -	node = rb_int_search_single(root, addr);
> >> -	if (node == NULL)
> >> -		return NULL;
> >> -
> >> -	return ioport_node(node);
> >> -}
> >> -
> >> -static int ioport_insert(struct rb_root *root, struct ioport *data)
> >> -{
> >> -	return rb_int_insert(root, &data->node);
> >> -}
> >> -
> >> -static void ioport_remove(struct rb_root *root, struct ioport *data)
> >> -{
> >> -	rb_int_erase(root, &data->node);
> >> -}
> >> -
> >> -static struct ioport *ioport_get(struct rb_root *root, u64 addr)
> >> -{
> >> -	struct ioport *ioport;
> >> -
> >> -	mutex_lock(&ioport_lock);
> >> -	ioport = ioport_search(root, addr);
> >> -	if (ioport)
> >> -		ioport->refcount++;
> >> -	mutex_unlock(&ioport_lock);
> >> -
> >> -	return ioport;
> >> -}
> >> -
> >> -/* Called with ioport_lock held. */
> >> -static void ioport_unregister(struct rb_root *root, struct ioport *data)
> >> -{
> >> -	ioport_remove(root, data);
> >> -	free(data);
> >> -}
> >> -
> >> -static void ioport_put(struct rb_root *root, struct ioport *data)
> >> -{
> >> -	mutex_lock(&ioport_lock);
> >> -	data->refcount--;
> >> -	if (data->remove && data->refcount == 0)
> >> -		ioport_unregister(root, data);
> >> -	mutex_unlock(&ioport_lock);
> >> -}
> >> -
> >> -int ioport__register(struct kvm *kvm, u16 port, struct ioport_operations *ops, int count, void *param)
> >> -{
> >> -	struct ioport *entry;
> >> -	int r;
> >> -
> >> -	entry = malloc(sizeof(*entry));
> >> -	if (entry == NULL)
> >> -		return -ENOMEM;
> >> -
> >> -	*entry = (struct ioport) {
> >> -		.node		= RB_INT_INIT(port, port + count),
> >> -		.ops		= ops,
> >> -		.priv		= param,
> >> -		/*
> >> -		 * Start from 0 because ioport__unregister() doesn't decrement
> >> -		 * the reference count.
> >> -		 */
> >> -		.refcount	= 0,
> >> -		.remove		= false,
> >> -	};
> >> -
> >> -	mutex_lock(&ioport_lock);
> >> -	r = ioport_insert(&ioport_tree, entry);
> >> -	if (r < 0)
> >> -		goto out_free;
> >> -	mutex_unlock(&ioport_lock);
> >> -
> >> -	return port;
> >> -
> >> -out_free:
> >> -	free(entry);
> >> -	mutex_unlock(&ioport_lock);
> >> -	return r;
> >> -}
> >> -
> >> -int ioport__unregister(struct kvm *kvm, u16 port)
> >> -{
> >> -	struct ioport *entry;
> >> -
> >> -	mutex_lock(&ioport_lock);
> >> -	entry = ioport_search(&ioport_tree, port);
> >> -	if (!entry) {
> >> -		mutex_unlock(&ioport_lock);
> >> -		return -ENOENT;
> >> -	}
> >> -	/* The same reasoning from kvm__deregister_mmio() applies. */
> >> -	if (entry->refcount == 0)
> >> -		ioport_unregister(&ioport_tree, entry);
> >> -	else
> >> -		entry->remove = true;
> >> -	mutex_unlock(&ioport_lock);
> >> -
> >> -	return 0;
> >> -}
> >> -
> >> -static const char *to_direction(int direction)
> >> -{
> >> -	if (direction == KVM_EXIT_IO_IN)
> >> -		return "IN";
> >> -	else
> >> -		return "OUT";
> >> -}
> >> -
> >> -static void ioport_error(u16 port, void *data, int direction, int size, u32 count)
> >> -{
> >> -	fprintf(stderr, "IO error: %s port=%x, size=%d, count=%u\n", to_direction(direction), port, size, count);
> >> -}
> >> -
> >> -bool kvm__emulate_io(struct kvm_cpu *vcpu, u16 port, void *data, int direction, int size, u32 count)
> >> -{
> >> -	struct ioport_operations *ops;
> >> -	bool ret = false;
> >> -	struct ioport *entry;
> >> -	void *ptr = data;
> >> -	struct kvm *kvm = vcpu->kvm;
> >> -
> >> -	entry = ioport_get(&ioport_tree, port);
> >> -	if (!entry)
> >> -		return kvm__emulate_pio(vcpu, port, data, direction,
> >> -					size, count);
> >> -
> >> -	ops	= entry->ops;
> >> -
> >> -	while (count--) {
> >> -		if (direction == KVM_EXIT_IO_IN && ops->io_in)
> >> -				ret = ops->io_in(entry, vcpu, port, ptr, size);
> >> -		else if (direction == KVM_EXIT_IO_OUT && ops->io_out)
> >> -				ret = ops->io_out(entry, vcpu, port, ptr, size);
> >> -
> >> -		ptr += size;
> >> -	}
> >> -
> >> -	ioport_put(&ioport_tree, entry);
> >> -
> >> -	if (ret)
> >> -		return true;
> >> -
> >> -	if (kvm->cfg.ioport_debug)
> >> -		ioport_error(port, data, direction, size, count);
> >> -
> >> -	return !kvm->cfg.ioport_debug;
> >> -}
> >> diff --git a/mmio.c b/mmio.c
> >> index 4cce1901..5249af39 100644
> >> --- a/mmio.c
> >> +++ b/mmio.c
> >> @@ -206,7 +206,7 @@ out:
> >>  	return true;
> >>  }
> >>  
> >> -bool kvm__emulate_pio(struct kvm_cpu *vcpu, u16 port, void *data,
> >> +bool kvm__emulate_io(struct kvm_cpu *vcpu, u16 port, void *data,
> >>  		     int direction, int size, u32 count)
> >>  {
> >>  	struct mmio_mapping *mmio;  
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