[PATCH 4/4] kvm tools: Use brlock in MMIO and IOPORT

[Sasha Levin <levinsasha928@gmail.com>]

Use brlock to protect mmio and ioport modules and make them
update-safe.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
---
 tools/kvm/ioport.c |   10 +++++++++-
 tools/kvm/mmio.c   |   17 +++++++++++++++--
 2 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/tools/kvm/ioport.c b/tools/kvm/ioport.c
index d0a1aa8..e00fb59 100644
--- a/tools/kvm/ioport.c
+++ b/tools/kvm/ioport.c
@@ -2,7 +2,7 @@
 
 #include "kvm/kvm.h"
 #include "kvm/util.h"
-
+#include "kvm/brlock.h"
 #include "kvm/rbtree-interval.h"
 #include "kvm/mutex.h"
 
@@ -84,6 +84,7 @@ u16 ioport__register(u16 port, struct ioport_operations *ops, int count, void *p
 {
 	struct ioport *entry;
 
+	br_write_lock();
 	if (port == IOPORT_EMPTY)
 		port = ioport__find_free_port();
 
@@ -105,6 +106,8 @@ u16 ioport__register(u16 port, struct ioport_operations *ops, int count, void *p
 
 	ioport_insert(&ioport_tree, entry);
 
+	br_write_unlock();
+
 	return port;
 }
 
@@ -127,6 +130,7 @@ bool kvm__emulate_io(struct kvm *kvm, u16 port, void *data, int direction, int s
 	bool ret = false;
 	struct ioport *entry;
 
+	br_read_lock();
 	entry = ioport_search(&ioport_tree, port);
 	if (!entry)
 		goto error;
@@ -141,11 +145,15 @@ bool kvm__emulate_io(struct kvm *kvm, u16 port, void *data, int direction, int s
 			ret = ops->io_out(entry, kvm, port, data, size, count);
 	}
 
+	br_read_unlock();
+
 	if (!ret)
 		goto error;
 
 	return true;
 error:
+	br_read_unlock();
+
 	if (ioport_debug)
 		ioport_error(port, data, direction, size, count);
 
diff --git a/tools/kvm/mmio.c b/tools/kvm/mmio.c
index ef986bf..a57abeb 100644
--- a/tools/kvm/mmio.c
+++ b/tools/kvm/mmio.c
@@ -1,5 +1,6 @@
 #include "kvm/kvm.h"
 #include "kvm/rbtree-interval.h"
+#include "kvm/brlock.h"
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -55,41 +56,53 @@ static const char *to_direction(u8 is_write)
 bool kvm__register_mmio(u64 phys_addr, u64 phys_addr_len, void (*kvm_mmio_callback_fn)(u64 addr, u8 *data, u32 len, u8 is_write))
 {
 	struct mmio_mapping *mmio;
+	int ret;
 
 	mmio = malloc(sizeof(*mmio));
 	if (mmio == NULL)
 		return false;
 
+	br_write_lock();
 	*mmio = (struct mmio_mapping) {
 		.node = RB_INT_INIT(phys_addr, phys_addr + phys_addr_len),
 		.kvm_mmio_callback_fn = kvm_mmio_callback_fn,
 	};
 
-	return mmio_insert(&mmio_tree, mmio);
+	ret = mmio_insert(&mmio_tree, mmio);
+	br_write_unlock();
+
+	return ret;
 }
 
 bool kvm__deregister_mmio(u64 phys_addr)
 {
 	struct mmio_mapping *mmio;
 
+	br_write_lock();
 	mmio = mmio_search_single(&mmio_tree, phys_addr);
 	if (mmio == NULL)
 		return false;
 
 	rb_int_erase(&mmio_tree, &mmio->node);
+	br_write_unlock();
+
 	free(mmio);
 	return true;
 }
 
 bool kvm__emulate_mmio(struct kvm *kvm, u64 phys_addr, u8 *data, u32 len, u8 is_write)
 {
-	struct mmio_mapping *mmio = mmio_search(&mmio_tree, phys_addr, len);
+	struct mmio_mapping *mmio;
+
+	br_read_lock();
+	mmio = mmio_search(&mmio_tree, phys_addr, len);
 
 	if (mmio)
 		mmio->kvm_mmio_callback_fn(phys_addr, data, len, is_write);
 	else
 		fprintf(stderr, "Warning: Ignoring MMIO %s at %016llx (length %u)\n",
 			to_direction(is_write), phys_addr, len);
+	br_read_unlock();
 
 	return true;
 }
-- 
1.7.5.rc3