[PATCH 07/11] vhost: convert vhost_umem_interval_tree to half closed intervals

Davidlohr Bueso
2019-10-03T20:20:53Z

The vhost_umem interval tree really wants [a, b) intervals,
not fully closed as currently. As such convert it to use the
new interval_tree_gen.h, and also rename the 'last' endpoint
in the node to 'end', which both a more suitable name for
the half closed interval and also reduces the chances of some
caller being missed.

Cc: Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
drivers/vhost/vhost.c | 19 +++++++++----------
drivers/vhost/vhost.h | 4 ++--
2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 36ca2cf419bf..80c3cca24dc7 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -28,7 +28,7 @@
#include <linux/sort.h>
#include <linux/sched/mm.h>
#include <linux/sched/signal.h>
-#include <linux/interval_tree_generic.h>
+#include <linux/interval_tree_gen.h>
#include <linux/nospec.h>

#include "vhost.h"
@@ -51,7 +51,7 @@ enum {

INTERVAL_TREE_DEFINE(struct vhost_umem_node,
rb, __u64, __subtree_last,
- START, LAST, static inline, vhost_umem_interval_tree);
+ START, END, static inline, vhost_umem_interval_tree);

#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
static void vhost_disable_cross_endian(struct vhost_virtqueue *vq)
@@ -1034,7 +1034,7 @@ static int vhost_new_umem_range(struct vhost_umem *umem,

node->start = start;
node->size = size;
- node->last = end;
+ node->end = end;
node->userspace_addr = userspace_addr;
node->perm = perm;
INIT_LIST_HEAD(&node->link);
@@ -1112,7 +1112,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
}
vhost_vq_meta_reset(dev);
if (vhost_new_umem_range(dev->iotlb, msg->iova, msg->size,
- msg->iova + msg->size - 1,
+ msg->iova + msg->size,
msg->uaddr, msg->perm)) {
ret = -ENOMEM;
break;
@@ -1126,7 +1126,7 @@ static int vhost_process_iotlb_msg(struct vhost_dev *dev,
}
vhost_vq_meta_reset(dev);
vhost_del_umem_range(dev->iotlb, msg->iova,
- msg->iova + msg->size - 1);
+ msg->iova + msg->size);
break;
default:
ret = -EINVAL;
@@ -1320,15 +1320,14 @@ static bool iotlb_access_ok(struct vhost_virtqueue *vq,
{
const struct vhost_umem_node *node;
struct vhost_umem *umem = vq->iotlb;
- u64 s = 0, size, orig_addr = addr, last = addr + len - 1;
+ u64 s = 0, size, orig_addr = addr, last = addr + len;

if (vhost_vq_meta_fetch(vq, addr, len, type))
return true;

while (len > s) {
node = vhost_umem_interval_tree_iter_first(&umem->umem_tree,
- addr,
- last);
+ addr, last);
if (node == NULL || node->start > addr) {
vhost_iotlb_miss(vq, addr, access);
return false;
@@ -1455,7 +1454,7 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
region->guest_phys_addr,
region->memory_size,
region->guest_phys_addr +
- region->memory_size - 1,
+ region->memory_size,
region->userspace_addr,
VHOST_ACCESS_RW))
goto err;
@@ -2055,7 +2054,7 @@ static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len,
}

node = vhost_umem_interval_tree_iter_first(&umem->umem_tree,
- addr, addr + len - 1);
+ addr, addr + len);
if (node == NULL || node->start > addr) {
if (umem != dev->iotlb) {
ret = -EFAULT;
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index e9ed2722b633..bb36cb9ed5ec 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -53,13 +53,13 @@ struct vhost_log {
};

#define START(node) ((node)->start)
-#define LAST(node) ((node)->last)
+#define END(node) ((node)->end)

struct vhost_umem_node {
struct rb_node rb;
struct list_head link;
__u64 start;
- __u64 last;
+ __u64 end;
__u64 size;
__u64 userspace_addr;
__u32 perm;
--
2.16.4