Aaron Lindsay <aa...@os.amperecomputing.com> writes:
> On Mar 09 10:08, Peter Maydell wrote: >> On Mon, 8 Mar 2021 at 20:14, Aaron Lindsay <aa...@os.amperecomputing.com> >> wrote: >> > >> > This allows plugins to query for full virtual-to-physical address >> > translation for a given `qemu_plugin_hwaddr` and stops exposing the >> > offset within the device itself. As this change breaks the API, >> > QEMU_PLUGIN_VERSION is incremented. >> > >> > Signed-off-by: Aaron Lindsay <aa...@os.amperecomputing.com> >> > --- >> >> >> > diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h >> > index c66507fe8f..2252ecf2f0 100644 >> > --- a/include/qemu/qemu-plugin.h >> > +++ b/include/qemu/qemu-plugin.h >> > @@ -47,7 +47,7 @@ typedef uint64_t qemu_plugin_id_t; >> > >> > extern QEMU_PLUGIN_EXPORT int qemu_plugin_version; >> > >> > -#define QEMU_PLUGIN_VERSION 0 >> > +#define QEMU_PLUGIN_VERSION 1 >> > >> > typedef struct { >> > /* string describing architecture */ >> > @@ -328,7 +328,7 @@ struct qemu_plugin_hwaddr >> > *qemu_plugin_get_hwaddr(qemu_plugin_meminfo_t info, >> > * offset will be into the appropriate block of RAM. >> > */ >> > bool qemu_plugin_hwaddr_is_io(const struct qemu_plugin_hwaddr *haddr); >> > -uint64_t qemu_plugin_hwaddr_device_offset(const struct qemu_plugin_hwaddr >> > *haddr); >> > +uint64_t qemu_plugin_hwaddr_phys_addr(const struct qemu_plugin_hwaddr >> > *haddr); >> >> >> This should have a documentation comment, since this is the public-facing >> API. > > I now see I neglected to update the comment right here the function > declaration, and will do so for v2. > > But are you asking for additional documentation beyond that change? If > so, where is the right place to add this? docs/devel/tcg-plugins.rst > doesn't seem to have much in the way of documentation for the actual > calls. The calls should be documented in @kerneldoc style comments in the main plugin header. Which reminds me I should be able to extract them into the tcg-plugins.rst document via sphinx. > >> Also, physical addresses aren't uniquely identifying, they're only valid >> in the context of a particular address space (think TrustZone, for instance), >> so the plugin-facing API should probably have some concept of how it >> distinguishes "this is an access for Secure 0x4000" from "this is an >> access for Non-Secure 0x4000". > > I agree it could be handy to expose address spaces in addition to the > addresses themselves. Do you believe doing so would change the form of > the interface in this patch, or could that be a logically separate > addition? I think information about address spaces should extracted be a separate query. > I have a secondary concern that it might be hard to expose address > spaces in an architecture-agnostic yet still-helpful way, but haven't > thought through that enough for it to be a firm opinion. Indeed - so I don't think we need to rush this without giving it some thought. As soft-freeze is only a few days away I don't think we want to rush an address space query API into 6.0. For most users I expect a assuming physical address is unique will work for the most part. But it's worth mentioning it might not be in the comment. > > -Aaron -- Alex Bennée