[Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Peter Maydell]

The xen pci_assign_dev_load_option_rom() currently creates a RAM
memory region with memory_region_init_ram_nomigrate(), and then
manually registers it with vmstate_register_ram(). In fact for
its only callsite, the 'owner' pointer we use for the init call
and the '&dev->qdev' pointer we use for the vmstate_register_ram()
call refer to the same object. Simplify the function to only
take a pointer to the device once instead of twice, and use
memory_region_init_ram() which automatically does the vmstate
register for us.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
This is a fairly trivial no-behaviour-change code cleanup, but
I've marked it as RFC because I don't have a setup for doing
more than just compile-testing Xen related patches.
This was found as part of a sweep through for code using
the _nomigrate versions of functions.

 hw/xen/xen_pt.h          | 2 +-
 hw/xen/xen_pt_graphics.c | 2 +-
 hw/xen/xen_pt_load_rom.c | 6 +++---
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/hw/xen/xen_pt.h b/hw/xen/xen_pt.h
index aa39a9aa5f..dbee3308fd 100644
--- a/hw/xen/xen_pt.h
+++ b/hw/xen/xen_pt.h
@@ -319,7 +319,7 @@ static inline bool xen_pt_has_msix_mapping(XenPCIPassthroughState *s, int bar)
 }
 
 extern void *pci_assign_dev_load_option_rom(PCIDevice *dev,
-                                            struct Object *owner, int *size,
+                                            int *size,
                                             unsigned int domain,
                                             unsigned int bus, unsigned int slot,
                                             unsigned int function);
diff --git a/hw/xen/xen_pt_graphics.c b/hw/xen/xen_pt_graphics.c
index 0f4c8d77e2..135c8df1e7 100644
--- a/hw/xen/xen_pt_graphics.c
+++ b/hw/xen/xen_pt_graphics.c
@@ -132,7 +132,7 @@ int xen_pt_unregister_vga_regions(XenHostPCIDevice *dev)
 static void *get_vgabios(XenPCIPassthroughState *s, int *size,
                        XenHostPCIDevice *dev)
 {
-    return pci_assign_dev_load_option_rom(&s->dev, OBJECT(&s->dev), size,
+    return pci_assign_dev_load_option_rom(&s->dev, size,
                                           dev->domain, dev->bus,
                                           dev->dev, dev->func);
 }
diff --git a/hw/xen/xen_pt_load_rom.c b/hw/xen/xen_pt_load_rom.c
index 71063c4d79..e6a86ca818 100644
--- a/hw/xen/xen_pt_load_rom.c
+++ b/hw/xen/xen_pt_load_rom.c
@@ -19,7 +19,7 @@
  * load the corresponding ROM data to RAM. If an error occurs while loading an
  * option ROM, we just ignore that option ROM and continue with the next one.
  */
-void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner,
+void *pci_assign_dev_load_option_rom(PCIDevice *dev,
                                      int *size, unsigned int domain,
                                      unsigned int bus, unsigned int slot,
                                      unsigned int function)
@@ -29,6 +29,7 @@ void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner,
     uint8_t val;
     struct stat st;
     void *ptr = NULL;
+    Object *owner = OBJECT(dev);
 
     /* If loading ROM from file, pci handles it */
     if (dev->romfile || !dev->rom_bar) {
@@ -59,8 +60,7 @@ void *pci_assign_dev_load_option_rom(PCIDevice *dev, struct Object *owner,
     fseek(fp, 0, SEEK_SET);
 
     snprintf(name, sizeof(name), "%s.rom", object_get_typename(owner));
-    memory_region_init_ram_nomigrate(&dev->rom, owner, name, st.st_size, &error_abort);
-    vmstate_register_ram(&dev->rom, &dev->qdev);
+    memory_region_init_ram(&dev->rom, owner, name, st.st_size, &error_abort);
     ptr = memory_region_get_ram_ptr(&dev->rom);
     memset(ptr, 0xff, st.st_size);
 
-- 
2.17.1

Re: [Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Anthony PERARD]

On Fri, Jun 01, 2018 at 06:59:10PM +0100, Peter Maydell wrote:
> The xen pci_assign_dev_load_option_rom() currently creates a RAM
> memory region with memory_region_init_ram_nomigrate(), and then
> manually registers it with vmstate_register_ram(). In fact for
> its only callsite, the 'owner' pointer we use for the init call
> and the '&dev->qdev' pointer we use for the vmstate_register_ram()
> call refer to the same object. Simplify the function to only
> take a pointer to the device once instead of twice, and use
> memory_region_init_ram() which automatically does the vmstate
> register for us.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
> This is a fairly trivial no-behaviour-change code cleanup, but
> I've marked it as RFC because I don't have a setup for doing
> more than just compile-testing Xen related patches.
> This was found as part of a sweep through for code using
> the _nomigrate versions of functions.

That patch looks fine, and seams fine after hacking my way into testing
the change.

Acked-by: Anthony PERARD <anthony.perard@citrix.com>

Thanks,

-- 
Anthony PERARD

Re: [Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Peter Maydell]

On 5 June 2018 at 17:55, Anthony PERARD <anthony.perard@citrix.com> wrote:
> On Fri, Jun 01, 2018 at 06:59:10PM +0100, Peter Maydell wrote:
>> The xen pci_assign_dev_load_option_rom() currently creates a RAM
>> memory region with memory_region_init_ram_nomigrate(), and then
>> manually registers it with vmstate_register_ram(). In fact for
>> its only callsite, the 'owner' pointer we use for the init call
>> and the '&dev->qdev' pointer we use for the vmstate_register_ram()
>> call refer to the same object. Simplify the function to only
>> take a pointer to the device once instead of twice, and use
>> memory_region_init_ram() which automatically does the vmstate
>> register for us.
>>
>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>> ---
>> This is a fairly trivial no-behaviour-change code cleanup, but
>> I've marked it as RFC because I don't have a setup for doing
>> more than just compile-testing Xen related patches.
>> This was found as part of a sweep through for code using
>> the _nomigrate versions of functions.
>
> That patch looks fine, and seams fine after hacking my way into testing
> the change.
>
> Acked-by: Anthony PERARD <anthony.perard@citrix.com>

Thanks for the review. Stefano, do you want to take it via the
xen subtree?

thanks
-- PMM

Re: [Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Anthony PERARD]

On Fri, Jun 15, 2018 at 11:06:47AM +0100, Peter Maydell wrote:
> On 5 June 2018 at 17:55, Anthony PERARD <anthony.perard@citrix.com> wrote:
> > On Fri, Jun 01, 2018 at 06:59:10PM +0100, Peter Maydell wrote:
> >> The xen pci_assign_dev_load_option_rom() currently creates a RAM
> >> memory region with memory_region_init_ram_nomigrate(), and then
> >> manually registers it with vmstate_register_ram(). In fact for
> >> its only callsite, the 'owner' pointer we use for the init call
> >> and the '&dev->qdev' pointer we use for the vmstate_register_ram()
> >> call refer to the same object. Simplify the function to only
> >> take a pointer to the device once instead of twice, and use
> >> memory_region_init_ram() which automatically does the vmstate
> >> register for us.
> >>
> >> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> >> ---
> >> This is a fairly trivial no-behaviour-change code cleanup, but
> >> I've marked it as RFC because I don't have a setup for doing
> >> more than just compile-testing Xen related patches.
> >> This was found as part of a sweep through for code using
> >> the _nomigrate versions of functions.
> >
> > That patch looks fine, and seams fine after hacking my way into testing
> > the change.
> >
> > Acked-by: Anthony PERARD <anthony.perard@citrix.com>
> 
> Thanks for the review. Stefano, do you want to take it via the
> xen subtree?

Hi Peter,

We don't have any other patch for xen, so feel free to commit this
one.

-- 
Anthony PERARD

Re: [Qemu-devel] [RFC] xen: Don't use memory_region_init_ram_nomigrate() in pci_assign_dev_load_option_rom()

[Stefano Stabellini]

On Fri, 15 Jun 2018, Anthony PERARD wrote:
> On Fri, Jun 15, 2018 at 11:06:47AM +0100, Peter Maydell wrote:
> > On 5 June 2018 at 17:55, Anthony PERARD <anthony.perard@citrix.com> wrote:
> > > On Fri, Jun 01, 2018 at 06:59:10PM +0100, Peter Maydell wrote:
> > >> The xen pci_assign_dev_load_option_rom() currently creates a RAM
> > >> memory region with memory_region_init_ram_nomigrate(), and then
> > >> manually registers it with vmstate_register_ram(). In fact for
> > >> its only callsite, the 'owner' pointer we use for the init call
> > >> and the '&dev->qdev' pointer we use for the vmstate_register_ram()
> > >> call refer to the same object. Simplify the function to only
> > >> take a pointer to the device once instead of twice, and use
> > >> memory_region_init_ram() which automatically does the vmstate
> > >> register for us.
> > >>
> > >> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> > >> ---
> > >> This is a fairly trivial no-behaviour-change code cleanup, but
> > >> I've marked it as RFC because I don't have a setup for doing
> > >> more than just compile-testing Xen related patches.
> > >> This was found as part of a sweep through for code using
> > >> the _nomigrate versions of functions.
> > >
> > > That patch looks fine, and seams fine after hacking my way into testing
> > > the change.
> > >
> > > Acked-by: Anthony PERARD <anthony.perard@citrix.com>
> > 
> > Thanks for the review. Stefano, do you want to take it via the
> > xen subtree?
> 
> Hi Peter,
> 
> We don't have any other patch for xen, so feel free to commit this
> one.

Yep, go ahead