Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-23 Thread Ian Molton
Alexander Graf wrote: I guess what you really want is some shm region between host and guess that you can use as ring buffer. Then you could run a timer on the host side to flush it or have some sort of callback when you urgently need to flush it manually. The benefit here is that you can

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-23 Thread Alexander Graf
On 23.02.2010, at 16:46, Ian Molton wrote: Alexander Graf wrote: I guess what you really want is some shm region between host and guess that you can use as ring buffer. Then you could run a timer on the host side to flush it or have some sort of callback when you urgently need to flush it

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-23 Thread Anthony Liguori
On 02/22/2010 11:47 AM, Ian Molton wrote: Anthony Liguori wrote: On 02/22/2010 10:46 AM, Ian Molton wrote: Anthony Liguori wrote: cpu_physical_memory_map(). But this function has some subtle characteristics. It may return a bounce buffer if you attempt to map MMIO

[Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Ian Molton
Hi folks, I've been updating some old patches which make use of a function to translate guest virtual addresses into pointers into the guest RAM. As I understand it qemu has guest virtual and physical addresses, the latter of which map somehow to host ram addresses. The function which the code

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Anthony Liguori
On 02/22/2010 07:59 AM, Ian Molton wrote: Hi folks, I've been updating some old patches which make use of a function to translate guest virtual addresses into pointers into the guest RAM. As I understand it qemu has guest virtual and physical addresses, the latter of which map somehow to host

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Ian Molton
Anthony Liguori wrote: cpu_physical_memory_map(). But this function has some subtle characteristics. It may return a bounce buffer if you attempt to map MMIO memory. There is a limited pool of bounce buffers available so it may return NULL in the event that it cannot allocate a bounce

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Anthony Liguori
On 02/22/2010 10:46 AM, Ian Molton wrote: Anthony Liguori wrote: cpu_physical_memory_map(). But this function has some subtle characteristics. It may return a bounce buffer if you attempt to map MMIO memory. There is a limited pool of bounce buffers available so it may return NULL in

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Ian Molton
Anthony Liguori wrote: On 02/22/2010 10:46 AM, Ian Molton wrote: Anthony Liguori wrote: cpu_physical_memory_map(). But this function has some subtle characteristics. It may return a bounce buffer if you attempt to map MMIO memory. There is a limited pool of bounce buffers available

Re: [Qemu-devel] Address translation - virt-phys-ram

2010-02-22 Thread Alexander Graf
Ian Molton wrote: Anthony Liguori wrote: On 02/22/2010 10:46 AM, Ian Molton wrote: Anthony Liguori wrote: cpu_physical_memory_map(). But this function has some subtle characteristics. It may return a bounce buffer if you attempt to map MMIO memory. There is a