Re: [Qemu-devel] [RFC v1] Add declarations for hierarchical memory region API

[Avi Kivity]

On 05/20/2011 12:04 AM, Stefan Weil wrote:
> Am 19.05.2011 16:12, schrieb Avi Kivity:
> > The memory API separates the attributes of a memory region (its size, 
> > how
> > reads or writes are handled, dirty logging, and coalescing) from 
> > where it
> > is mapped and whether it is enabled. This allows a device to configure
> > a memory region once, then hand it off to its parent bus to map it 
> > according
> > to the bus configuration.
> >
> > Hierarchical registration also allows a device to compose a region 
> > out of
> > a number of sub-regions with different properties; for example some 
> > may be
> > RAM while others may be MMIO.

> > --- /dev/null
> > +++ b/memory.h
> > @@ -0,0 +1,142 @@
> > +#ifndef MEMORY_H
> > +#define MEMORY_H
> > +
> > +#include <stdint.h>
> > +#include <stdbool.h>
>
> stdbool.h is already included in qemu-common.h,
> stdint.h (indirectly) too.
>
> Therefore both include statements can be removed.

We shouldn't rely on indirect includes, it makes updating headers very 
hard.  Each header should #include what it directly needs and no more.

> > +typedef struct CoalescedMemoryRange CoalescedMemoryRange;
> > +
> > +struct CoalescedMemoryRange {
> > + target_phys_addr_t start;
> > + target_phys_addr_t size;
> > + QTAILQ_ENTRY(coalesced_ranges) link;
> > +};
> > +
> > +struct MemoryRegion {
> > + /* All fields are private - violators will be prosecuted */
>
> Is it possible to move this private declaration into the implementation
> file (or a private header file if the declaration is needed by more than
> one file)?


No, the structure size is needed by clients.

--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.