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* [PATCH v2 0/5] VFIO device init cleanup
@ 2023-11-16  7:59 Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 1/5] vfio/pci: Move VFIODevice initializations in vfio_instance_init Zhenzhong Duan
                   ` (4 more replies)
  0 siblings, 5 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan

Hi,

This is a cleanup based on Cédric's suggestion at
https://lists.gnu.org/archive/html/qemu-devel/2023-11/msg02722.html

VFIO device initializations are all moved from realize to instance_init.

Based on https://github.com/legoater/qemu/commits/vfio-8.2

Thanks
Zhenzhong

Changelog:
v2: Append a new patch to introduce vfio_device_init (Cédric)
    Add RB

Zhenzhong Duan (5):
  vfio/pci: Move VFIODevice initializations in vfio_instance_init
  vfio/platform: Move VFIODevice initializations in
    vfio_platform_instance_init
  vfio/ap: Move VFIODevice initializations in vfio_ap_instance_init
  vfio/ccw: Move VFIODevice initializations in vfio_ccw_instance_init
  vfio: Introduce a helper function to initialize VFIODevice

 include/hw/vfio/vfio-common.h |  2 ++
 hw/vfio/ap.c                  | 22 +++++++++-------------
 hw/vfio/ccw.c                 | 26 +++++++++++---------------
 hw/vfio/helpers.c             | 11 +++++++++++
 hw/vfio/pci.c                 |  8 ++++----
 hw/vfio/platform.c            |  8 +++-----
 6 files changed, 40 insertions(+), 37 deletions(-)

-- 
2.34.1



^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2 1/5] vfio/pci: Move VFIODevice initializations in vfio_instance_init
  2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
@ 2023-11-16  7:59 ` Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 2/5] vfio/platform: Move VFIODevice initializations in vfio_platform_instance_init Zhenzhong Duan
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan, Philippe Mathieu-Daudé

Some of the VFIODevice initializations is in vfio_realize,
move all of them in vfio_instance_init.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/vfio/pci.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index b23b492cce..5a2b7a2d6b 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2969,9 +2969,6 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
     if (vfio_device_get_name(vbasedev, errp)) {
         return;
     }
-    vbasedev->ops = &vfio_pci_ops;
-    vbasedev->type = VFIO_DEVICE_TYPE_PCI;
-    vbasedev->dev = DEVICE(vdev);
 
     /*
      * Mediated devices *might* operate compatibly with discarding of RAM, but
@@ -3320,6 +3317,7 @@ static void vfio_instance_init(Object *obj)
 {
     PCIDevice *pci_dev = PCI_DEVICE(obj);
     VFIOPCIDevice *vdev = VFIO_PCI(obj);
+    VFIODevice *vbasedev = &vdev->vbasedev;
 
     device_add_bootindex_property(obj, &vdev->bootindex,
                                   "bootindex", NULL,
@@ -3328,7 +3326,11 @@ static void vfio_instance_init(Object *obj)
     vdev->host.bus = ~0U;
     vdev->host.slot = ~0U;
     vdev->host.function = ~0U;
-    vdev->vbasedev.fd = -1;
+
+    vbasedev->type = VFIO_DEVICE_TYPE_PCI;
+    vbasedev->ops = &vfio_pci_ops;
+    vbasedev->dev = DEVICE(vdev);
+    vbasedev->fd = -1;
 
     vdev->nv_gpudirect_clique = 0xFF;
 
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 2/5] vfio/platform: Move VFIODevice initializations in vfio_platform_instance_init
  2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 1/5] vfio/pci: Move VFIODevice initializations in vfio_instance_init Zhenzhong Duan
@ 2023-11-16  7:59 ` Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 3/5] vfio/ap: Move VFIODevice initializations in vfio_ap_instance_init Zhenzhong Duan
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan, Philippe Mathieu-Daudé

Some of the VFIODevice initializations is in vfio_platform_realize,
move all of them in vfio_platform_instance_init.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/vfio/platform.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index a97d9c6234..506eb8193f 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -581,10 +581,6 @@ static void vfio_platform_realize(DeviceState *dev, Error **errp)
     VFIODevice *vbasedev = &vdev->vbasedev;
     int i, ret;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
-    vbasedev->dev = dev;
-    vbasedev->ops = &vfio_platform_ops;
-
     qemu_mutex_init(&vdev->intp_mutex);
 
     trace_vfio_platform_realize(vbasedev->sysfsdev ?
@@ -659,8 +655,12 @@ static Property vfio_platform_dev_properties[] = {
 static void vfio_platform_instance_init(Object *obj)
 {
     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(obj);
+    VFIODevice *vbasedev = &vdev->vbasedev;
 
-    vdev->vbasedev.fd = -1;
+    vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
+    vbasedev->ops = &vfio_platform_ops;
+    vbasedev->dev = DEVICE(vdev);
+    vbasedev->fd = -1;
 }
 
 #ifdef CONFIG_IOMMUFD
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 3/5] vfio/ap: Move VFIODevice initializations in vfio_ap_instance_init
  2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 1/5] vfio/pci: Move VFIODevice initializations in vfio_instance_init Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 2/5] vfio/platform: Move VFIODevice initializations in vfio_platform_instance_init Zhenzhong Duan
@ 2023-11-16  7:59 ` Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 4/5] vfio/ccw: Move VFIODevice initializations in vfio_ccw_instance_init Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 5/5] vfio: Introduce a helper function to initialize VFIODevice Zhenzhong Duan
  4 siblings, 0 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan, Philippe Mathieu-Daudé, Eric Farman,
	Tony Krowiak, Halil Pasic, Jason Herne, Thomas Huth,
	open list:vfio-ap

Some of the VFIODevice initializations is in vfio_ap_realize,
move all of them in vfio_ap_instance_init.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
---
 hw/vfio/ap.c | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
index b21f92291e..31ea9644c5 100644
--- a/hw/vfio/ap.c
+++ b/hw/vfio/ap.c
@@ -164,18 +164,6 @@ static void vfio_ap_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    vbasedev->ops = &vfio_ap_ops;
-    vbasedev->type = VFIO_DEVICE_TYPE_AP;
-    vbasedev->dev = dev;
-
-    /*
-     * vfio-ap devices operate in a way compatible with discarding of
-     * memory in RAM blocks, as no pages are pinned in the host.
-     * This needs to be set before vfio_get_device() for vfio common to
-     * handle ram_block_discard_disable().
-     */
-    vapdev->vdev.ram_block_discard_allowed = true;
-
     ret = vfio_attach_device(vbasedev->name, vbasedev,
                              &address_space_memory, errp);
     if (ret) {
@@ -236,8 +224,20 @@ static const VMStateDescription vfio_ap_vmstate = {
 static void vfio_ap_instance_init(Object *obj)
 {
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(obj);
+    VFIODevice *vbasedev = &vapdev->vdev;
 
-    vapdev->vdev.fd = -1;
+    vbasedev->type = VFIO_DEVICE_TYPE_AP;
+    vbasedev->ops = &vfio_ap_ops;
+    vbasedev->dev = DEVICE(vapdev);
+    vbasedev->fd = -1;
+
+    /*
+     * vfio-ap devices operate in a way compatible with discarding of
+     * memory in RAM blocks, as no pages are pinned in the host.
+     * This needs to be set before vfio_get_device() for vfio common to
+     * handle ram_block_discard_disable().
+     */
+    vbasedev->ram_block_discard_allowed = true;
 }
 
 #ifdef CONFIG_IOMMUFD
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 4/5] vfio/ccw: Move VFIODevice initializations in vfio_ccw_instance_init
  2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
                   ` (2 preceding siblings ...)
  2023-11-16  7:59 ` [PATCH v2 3/5] vfio/ap: Move VFIODevice initializations in vfio_ap_instance_init Zhenzhong Duan
@ 2023-11-16  7:59 ` Zhenzhong Duan
  2023-11-16  7:59 ` [PATCH v2 5/5] vfio: Introduce a helper function to initialize VFIODevice Zhenzhong Duan
  4 siblings, 0 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan, Philippe Mathieu-Daudé, Eric Farman,
	Thomas Huth, Matthew Rosato, open list:S390 general arch...

Some of the VFIODevice initializations is in vfio_ccw_realize,
move all of them in vfio_ccw_instance_init.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
---
 hw/vfio/ccw.c | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
index b116b10fe7..8de2fd809b 100644
--- a/hw/vfio/ccw.c
+++ b/hw/vfio/ccw.c
@@ -594,20 +594,6 @@ static void vfio_ccw_realize(DeviceState *dev, Error **errp)
         return;
     }
 
-    vbasedev->ops = &vfio_ccw_ops;
-    vbasedev->type = VFIO_DEVICE_TYPE_CCW;
-    vbasedev->dev = dev;
-
-    /*
-     * All vfio-ccw devices are believed to operate in a way compatible with
-     * discarding of memory in RAM blocks, ie. pages pinned in the host are
-     * in the current working set of the guest driver and therefore never
-     * overlap e.g., with pages available to the guest balloon driver.  This
-     * needs to be set before vfio_get_device() for vfio common to handle
-     * ram_block_discard_disable().
-     */
-    vbasedev->ram_block_discard_allowed = true;
-
     ret = vfio_attach_device(cdev->mdevid, vbasedev,
                              &address_space_memory, errp);
     if (ret) {
@@ -695,8 +681,22 @@ static const VMStateDescription vfio_ccw_vmstate = {
 static void vfio_ccw_instance_init(Object *obj)
 {
     VFIOCCWDevice *vcdev = VFIO_CCW(obj);
+    VFIODevice *vbasedev = &vcdev->vdev;
+
+    vbasedev->type = VFIO_DEVICE_TYPE_CCW;
+    vbasedev->ops = &vfio_ccw_ops;
+    vbasedev->dev = DEVICE(vcdev);
+    vbasedev->fd = -1;
 
-    vcdev->vdev.fd = -1;
+    /*
+     * All vfio-ccw devices are believed to operate in a way compatible with
+     * discarding of memory in RAM blocks, ie. pages pinned in the host are
+     * in the current working set of the guest driver and therefore never
+     * overlap e.g., with pages available to the guest balloon driver.  This
+     * needs to be set before vfio_get_device() for vfio common to handle
+     * ram_block_discard_disable().
+     */
+    vbasedev->ram_block_discard_allowed = true;
 }
 
 #ifdef CONFIG_IOMMUFD
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2 5/5] vfio: Introduce a helper function to initialize VFIODevice
  2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
                   ` (3 preceding siblings ...)
  2023-11-16  7:59 ` [PATCH v2 4/5] vfio/ccw: Move VFIODevice initializations in vfio_ccw_instance_init Zhenzhong Duan
@ 2023-11-16  7:59 ` Zhenzhong Duan
  4 siblings, 0 replies; 6+ messages in thread
From: Zhenzhong Duan @ 2023-11-16  7:59 UTC (permalink / raw)
  To: qemu-devel
  Cc: alex.williamson, clg, jgg, nicolinc, joao.m.martins, eric.auger,
	peterx, jasowang, kevin.tian, yi.l.liu, yi.y.sun, chao.p.peng,
	Zhenzhong Duan, Thomas Huth, Tony Krowiak, Halil Pasic,
	Jason Herne, Eric Farman, Matthew Rosato,
	open list:S390 general arch...

Introduce a helper function to replace the common code to initialize
VFIODevice in pci, platform, ap and ccw VFIO device.

No functional change intended.

Suggested-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
---
 include/hw/vfio/vfio-common.h |  2 ++
 hw/vfio/ap.c                  |  8 ++------
 hw/vfio/ccw.c                 |  8 ++------
 hw/vfio/helpers.c             | 11 +++++++++++
 hw/vfio/pci.c                 |  6 ++----
 hw/vfio/platform.c            |  6 ++----
 6 files changed, 21 insertions(+), 20 deletions(-)

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 7954531d05..fa430cb288 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -256,4 +256,6 @@ int vfio_get_dirty_bitmap(const VFIOContainerBase *bcontainer, uint64_t iova,
 
 int vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
 void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
+void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
+                      DeviceState *dev, bool ram_discard);
 #endif /* HW_VFIO_VFIO_COMMON_H */
diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
index 31ea9644c5..84c83f66fe 100644
--- a/hw/vfio/ap.c
+++ b/hw/vfio/ap.c
@@ -226,18 +226,14 @@ static void vfio_ap_instance_init(Object *obj)
     VFIOAPDevice *vapdev = VFIO_AP_DEVICE(obj);
     VFIODevice *vbasedev = &vapdev->vdev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_AP;
-    vbasedev->ops = &vfio_ap_ops;
-    vbasedev->dev = DEVICE(vapdev);
-    vbasedev->fd = -1;
-
     /*
      * vfio-ap devices operate in a way compatible with discarding of
      * memory in RAM blocks, as no pages are pinned in the host.
      * This needs to be set before vfio_get_device() for vfio common to
      * handle ram_block_discard_disable().
      */
-    vbasedev->ram_block_discard_allowed = true;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops,
+                     DEVICE(vapdev), true);
 }
 
 #ifdef CONFIG_IOMMUFD
diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
index 8de2fd809b..0b1873e922 100644
--- a/hw/vfio/ccw.c
+++ b/hw/vfio/ccw.c
@@ -683,11 +683,6 @@ static void vfio_ccw_instance_init(Object *obj)
     VFIOCCWDevice *vcdev = VFIO_CCW(obj);
     VFIODevice *vbasedev = &vcdev->vdev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_CCW;
-    vbasedev->ops = &vfio_ccw_ops;
-    vbasedev->dev = DEVICE(vcdev);
-    vbasedev->fd = -1;
-
     /*
      * All vfio-ccw devices are believed to operate in a way compatible with
      * discarding of memory in RAM blocks, ie. pages pinned in the host are
@@ -696,7 +691,8 @@ static void vfio_ccw_instance_init(Object *obj)
      * needs to be set before vfio_get_device() for vfio common to handle
      * ram_block_discard_disable().
      */
-    vbasedev->ram_block_discard_allowed = true;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_CCW, &vfio_ccw_ops,
+                     DEVICE(vcdev), true);
 }
 
 #ifdef CONFIG_IOMMUFD
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index 3592c3d54e..6789870802 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -652,3 +652,14 @@ void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
     }
     vbasedev->fd = fd;
 }
+
+void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
+                      DeviceState *dev, bool ram_discard)
+{
+    vbasedev->type = type;
+    vbasedev->ops = ops;
+    vbasedev->dev = dev;
+    vbasedev->fd = -1;
+
+    vbasedev->ram_block_discard_allowed = ram_discard;
+}
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 5a2b7a2d6b..31ad27d716 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3327,10 +3327,8 @@ static void vfio_instance_init(Object *obj)
     vdev->host.slot = ~0U;
     vdev->host.function = ~0U;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_PCI;
-    vbasedev->ops = &vfio_pci_ops;
-    vbasedev->dev = DEVICE(vdev);
-    vbasedev->fd = -1;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PCI, &vfio_pci_ops,
+                     DEVICE(vdev), false);
 
     vdev->nv_gpudirect_clique = 0xFF;
 
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index 506eb8193f..a8d9b7da63 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -657,10 +657,8 @@ static void vfio_platform_instance_init(Object *obj)
     VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(obj);
     VFIODevice *vbasedev = &vdev->vbasedev;
 
-    vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM;
-    vbasedev->ops = &vfio_platform_ops;
-    vbasedev->dev = DEVICE(vdev);
-    vbasedev->fd = -1;
+    vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PLATFORM, &vfio_platform_ops,
+                     DEVICE(vdev), false);
 }
 
 #ifdef CONFIG_IOMMUFD
-- 
2.34.1



^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2023-11-16  8:16 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2023-11-16  7:59 [PATCH v2 0/5] VFIO device init cleanup Zhenzhong Duan
2023-11-16  7:59 ` [PATCH v2 1/5] vfio/pci: Move VFIODevice initializations in vfio_instance_init Zhenzhong Duan
2023-11-16  7:59 ` [PATCH v2 2/5] vfio/platform: Move VFIODevice initializations in vfio_platform_instance_init Zhenzhong Duan
2023-11-16  7:59 ` [PATCH v2 3/5] vfio/ap: Move VFIODevice initializations in vfio_ap_instance_init Zhenzhong Duan
2023-11-16  7:59 ` [PATCH v2 4/5] vfio/ccw: Move VFIODevice initializations in vfio_ccw_instance_init Zhenzhong Duan
2023-11-16  7:59 ` [PATCH v2 5/5] vfio: Introduce a helper function to initialize VFIODevice Zhenzhong Duan

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