On 4/9/2020 8:43 PM, Jason Wang wrote:
On 2020/4/9 下午6:41, Arnd Bergmann wrote:
On Thu, Mar 26, 2020 at 3:08 PM Jason Wang <jasowang@xxxxxxxxxx> wrote:
From: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
This commit introduced two layers to drive IFC VF:
(1) ifcvf_base layer, which handles IFC VF NIC hardware operations and
configurations.
(2) ifcvf_main layer, which complies to VDPA bus framework,
implemented device operations for VDPA bus, handles device probe,
bus attaching, vring operations, etc.
Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
Signed-off-by: Bie Tiwei <tiwei.bie@xxxxxxxxx>
Signed-off-by: Wang Xiao <xiao.w.wang@xxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
+
+#define IFCVF_QUEUE_ALIGNMENT PAGE_SIZE
+#define IFCVF_QUEUE_MAX 32768
+static u16 ifcvf_vdpa_get_vq_align(struct vdpa_device *vdpa_dev)
+{
+ return IFCVF_QUEUE_ALIGNMENT;
+}
This fails to build on arm64 with 64kb page size (found in linux-next):
/drivers/vdpa/ifcvf/ifcvf_main.c: In function 'ifcvf_vdpa_get_vq_align':
arch/arm64/include/asm/page-def.h:17:20: error: conversion from 'long
unsigned int' to 'u16' {aka 'short unsigned int'} changes value from
'65536' to '0' [-Werror=overflow]
17 | #define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
| ^
drivers/vdpa/ifcvf/ifcvf_base.h:37:31: note: in expansion of macro
'PAGE_SIZE'
37 | #define IFCVF_QUEUE_ALIGNMENT PAGE_SIZE
| ^~~~~~~~~
drivers/vdpa/ifcvf/ifcvf_main.c:231:9: note: in expansion of macro
'IFCVF_QUEUE_ALIGNMENT'
231 | return IFCVF_QUEUE_ALIGNMENT;
| ^~~~~~~~~~~~~~~~~~~~~
It's probably good enough to just not allow the driver to be built in
that
configuration as it's fairly rare but unfortunately there is no
simple Kconfig
symbol for it.
Or I think the 64KB alignment is probably more than enough.
Ling Shan, can we use smaller value here?
Thanks
sure, we just need it page aligned, this value is only used in
get_vq_align(). I will try to find a arm64 machine and debug on this issue
Thanks!
In a similar driver, we did
config VMXNET3
tristate "VMware VMXNET3 ethernet driver"
depends on PCI && INET
depends on !(PAGE_SIZE_64KB || ARM64_64K_PAGES || \
IA64_PAGE_SIZE_64KB || MICROBLAZE_64K_PAGES || \
PARISC_PAGE_SIZE_64KB || PPC_64K_PAGES)
I think we should probably make PAGE_SIZE_64KB a global symbol
in arch/Kconfig and have it selected by the other symbols so drivers
like yours can add a dependency for it.
Arnd
