[PATCH 4.16 091/113] virt: vbox: Add vbg_req_free() helper function

From: Greg Kroah-Hartman
Date: Mon Apr 30 2018 - 15:37:20 EST


4.16-stable review patch. If anyone has any objections, please let me know.

------------------

From: Hans de Goede <hdegoede@xxxxxxxxxx>

commit f6f9885b0531163f72c7bf898a0ab1ba4c7d5de6 upstream.

This is a preparation patch for fixing issues on x86_64 virtual-machines
with more then 4G of RAM, atm we pass __GFP_DMA32 to kmalloc, but kmalloc
does not honor that, so we need to switch to get_pages, which means we
will not be able to use kfree to free memory allocated with vbg_alloc_req.

While at it also remove a comment on a vbg_alloc_req call which talks
about Windows (inherited from the vbox upstream cross-platform code).

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/virt/vboxguest/vboxguest_core.c | 66 ++++++++++++++++---------------
drivers/virt/vboxguest/vboxguest_core.h | 1
drivers/virt/vboxguest/vboxguest_utils.c | 14 +++++-
3 files changed, 47 insertions(+), 34 deletions(-)

--- a/drivers/virt/vboxguest/vboxguest_core.c
+++ b/drivers/virt/vboxguest/vboxguest_core.c
@@ -114,7 +114,7 @@ static void vbg_guest_mappings_init(stru
}

out:
- kfree(req);
+ vbg_req_free(req, sizeof(*req));
kfree(pages);
}

@@ -144,7 +144,7 @@ static void vbg_guest_mappings_exit(stru

rc = vbg_req_perform(gdev, req);

- kfree(req);
+ vbg_req_free(req, sizeof(*req));

if (rc < 0) {
vbg_err("%s error: %d\n", __func__, rc);
@@ -214,8 +214,8 @@ static int vbg_report_guest_info(struct
ret = vbg_status_code_to_errno(rc);

out_free:
- kfree(req2);
- kfree(req1);
+ vbg_req_free(req2, sizeof(*req2));
+ vbg_req_free(req1, sizeof(*req1));
return ret;
}

@@ -245,7 +245,7 @@ static int vbg_report_driver_status(stru
if (rc == VERR_NOT_IMPLEMENTED) /* Compatibility with older hosts. */
rc = VINF_SUCCESS;

- kfree(req);
+ vbg_req_free(req, sizeof(*req));

return vbg_status_code_to_errno(rc);
}
@@ -431,7 +431,7 @@ static int vbg_heartbeat_host_config(str
rc = vbg_req_perform(gdev, req);
do_div(req->interval_ns, 1000000); /* ns -> ms */
gdev->heartbeat_interval_ms = req->interval_ns;
- kfree(req);
+ vbg_req_free(req, sizeof(*req));

return vbg_status_code_to_errno(rc);
}
@@ -454,12 +454,6 @@ static int vbg_heartbeat_init(struct vbg
if (ret < 0)
return ret;

- /*
- * Preallocate the request to use it from the timer callback because:
- * 1) on Windows vbg_req_alloc must be called at IRQL <= APC_LEVEL
- * and the timer callback runs at DISPATCH_LEVEL;
- * 2) avoid repeated allocations.
- */
gdev->guest_heartbeat_req = vbg_req_alloc(
sizeof(*gdev->guest_heartbeat_req),
VMMDEVREQ_GUEST_HEARTBEAT);
@@ -481,8 +475,8 @@ static void vbg_heartbeat_exit(struct vb
{
del_timer_sync(&gdev->heartbeat_timer);
vbg_heartbeat_host_config(gdev, false);
- kfree(gdev->guest_heartbeat_req);
-
+ vbg_req_free(gdev->guest_heartbeat_req,
+ sizeof(*gdev->guest_heartbeat_req));
}

/**
@@ -543,7 +537,7 @@ static int vbg_reset_host_event_filter(s
if (rc < 0)
vbg_err("%s error, rc: %d\n", __func__, rc);

- kfree(req);
+ vbg_req_free(req, sizeof(*req));
return vbg_status_code_to_errno(rc);
}

@@ -617,7 +611,7 @@ static int vbg_set_session_event_filter(

out:
mutex_unlock(&gdev->session_mutex);
- kfree(req);
+ vbg_req_free(req, sizeof(*req));

return ret;
}
@@ -642,7 +636,7 @@ static int vbg_reset_host_capabilities(s
if (rc < 0)
vbg_err("%s error, rc: %d\n", __func__, rc);

- kfree(req);
+ vbg_req_free(req, sizeof(*req));
return vbg_status_code_to_errno(rc);
}

@@ -712,7 +706,7 @@ static int vbg_set_session_capabilities(

out:
mutex_unlock(&gdev->session_mutex);
- kfree(req);
+ vbg_req_free(req, sizeof(*req));

return ret;
}
@@ -749,7 +743,7 @@ static int vbg_query_host_version(struct
}

out:
- kfree(req);
+ vbg_req_free(req, sizeof(*req));
return ret;
}

@@ -847,11 +841,16 @@ int vbg_core_init(struct vbg_dev *gdev,
return 0;

err_free_reqs:
- kfree(gdev->mouse_status_req);
- kfree(gdev->ack_events_req);
- kfree(gdev->cancel_req);
- kfree(gdev->mem_balloon.change_req);
- kfree(gdev->mem_balloon.get_req);
+ vbg_req_free(gdev->mouse_status_req,
+ sizeof(*gdev->mouse_status_req));
+ vbg_req_free(gdev->ack_events_req,
+ sizeof(*gdev->ack_events_req));
+ vbg_req_free(gdev->cancel_req,
+ sizeof(*gdev->cancel_req));
+ vbg_req_free(gdev->mem_balloon.change_req,
+ sizeof(*gdev->mem_balloon.change_req));
+ vbg_req_free(gdev->mem_balloon.get_req,
+ sizeof(*gdev->mem_balloon.get_req));
return ret;
}

@@ -872,11 +871,16 @@ void vbg_core_exit(struct vbg_dev *gdev)
vbg_reset_host_capabilities(gdev);
vbg_core_set_mouse_status(gdev, 0);

- kfree(gdev->mouse_status_req);
- kfree(gdev->ack_events_req);
- kfree(gdev->cancel_req);
- kfree(gdev->mem_balloon.change_req);
- kfree(gdev->mem_balloon.get_req);
+ vbg_req_free(gdev->mouse_status_req,
+ sizeof(*gdev->mouse_status_req));
+ vbg_req_free(gdev->ack_events_req,
+ sizeof(*gdev->ack_events_req));
+ vbg_req_free(gdev->cancel_req,
+ sizeof(*gdev->cancel_req));
+ vbg_req_free(gdev->mem_balloon.change_req,
+ sizeof(*gdev->mem_balloon.change_req));
+ vbg_req_free(gdev->mem_balloon.get_req,
+ sizeof(*gdev->mem_balloon.get_req));
}

/**
@@ -1415,7 +1419,7 @@ static int vbg_ioctl_write_core_dump(str
req->flags = dump->u.in.flags;
dump->hdr.rc = vbg_req_perform(gdev, req);

- kfree(req);
+ vbg_req_free(req, sizeof(*req));
return 0;
}

@@ -1513,7 +1517,7 @@ int vbg_core_set_mouse_status(struct vbg
if (rc < 0)
vbg_err("%s error, rc: %d\n", __func__, rc);

- kfree(req);
+ vbg_req_free(req, sizeof(*req));
return vbg_status_code_to_errno(rc);
}

--- a/drivers/virt/vboxguest/vboxguest_core.h
+++ b/drivers/virt/vboxguest/vboxguest_core.h
@@ -173,6 +173,7 @@ void vbg_linux_mouse_event(struct vbg_de

/* Private (non exported) functions form vboxguest_utils.c */
void *vbg_req_alloc(size_t len, enum vmmdev_request_type req_type);
+void vbg_req_free(void *req, size_t len);
int vbg_req_perform(struct vbg_dev *gdev, void *req);
int vbg_hgcm_call32(
struct vbg_dev *gdev, u32 client_id, u32 function, u32 timeout_ms,
--- a/drivers/virt/vboxguest/vboxguest_utils.c
+++ b/drivers/virt/vboxguest/vboxguest_utils.c
@@ -82,6 +82,14 @@ void *vbg_req_alloc(size_t len, enum vmm
return req;
}

+void vbg_req_free(void *req, size_t len)
+{
+ if (!req)
+ return;
+
+ kfree(req);
+}
+
/* Note this function returns a VBox status code, not a negative errno!! */
int vbg_req_perform(struct vbg_dev *gdev, void *req)
{
@@ -137,7 +145,7 @@ int vbg_hgcm_connect(struct vbg_dev *gde
rc = hgcm_connect->header.result;
}

- kfree(hgcm_connect);
+ vbg_req_free(hgcm_connect, sizeof(*hgcm_connect));

*vbox_status = rc;
return 0;
@@ -166,7 +174,7 @@ int vbg_hgcm_disconnect(struct vbg_dev *
if (rc >= 0)
rc = hgcm_disconnect->header.result;

- kfree(hgcm_disconnect);
+ vbg_req_free(hgcm_disconnect, sizeof(*hgcm_disconnect));

*vbox_status = rc;
return 0;
@@ -623,7 +631,7 @@ int vbg_hgcm_call(struct vbg_dev *gdev,
}

if (!leak_it)
- kfree(call);
+ vbg_req_free(call, size);

free_bounce_bufs:
if (bounce_bufs) {