Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-04 Thread Lyu Mitnick
Hello Stefan, 2011/4/3 Stefan Hajnoczi > On Sat, Apr 2, 2011 at 8:03 PM, Lyu Mitnick wrote: > > Hello Stefan, > > I have take a look at block.c. But I am a little confused about the > meaning > > of synchronous/asynchronous i/o. I know the two concept in a operating > > system. However I am no

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-03 Thread Stefan Hajnoczi
On Sat, Apr 2, 2011 at 8:03 PM, Lyu Mitnick wrote: > Hello Stefan, > I have take a look at block.c. But I am a little confused about the meaning > of synchronous/asynchronous i/o. I know the two concept in a operating > system.  However I am not sure whether it is analogous in virtual machine. Yo

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-02 Thread Lyu Mitnick
Hello Stefan, I have take a look at block.c. But I am a little confused about the meaning of synchronous/asynchronous i/o. I know the two concept in a operating system. However I am not sure whether it is analogous in virtual machine. 2011/4/2 Stefan Hajnoczi > On Fri, Apr 1, 2011 at 7:29 PM,

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-02 Thread Stefan Hajnoczi
On Fri, Apr 1, 2011 at 7:29 PM, Lyu Mitnick wrote: > Hello > I have some question about asynchronous i/o in QEMU block driver: Why a file > format with asynchronous i/o support(ex. qcow) doesn't need to register > bdrv_read/bdrv_write which is registered in vhd file format?? Would qcow > block dri

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-01 Thread Lyu Mitnick
Hello I have some question about asynchronous i/o in QEMU block driver: Why a file format with asynchronous i/o support(ex. qcow) doesn't need to register bdrv_read/bdrv_write which is registered in vhd file format?? Would qcow block driver also support synchronous i/o?? thanks a lot Mitnick 20

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-01 Thread Kevin Wolf
Am 01.04.2011 17:15, schrieb Lyu Mitnick: > Hello Stefan > > Hello Mitnick, > > asynchronous i/o is also missing in block/vpc.c. > > All newer block drivers support asynchronous reads and writes, > only some old drivers don't. > > So adding asynchronous i/o to at least some

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-01 Thread Stefan Weil
Am 01.04.2011 17:15, schrieb Lyu Mitnick: Hello Stefan Hello Mitnick, asynchronous i/o is also missing in block/vpc.c. All newer block drivers support asynchronous reads and writes, only some old drivers don't. So adding asynchronous i/o to at least some of the old drivers

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-04-01 Thread Lyu Mitnick
Hello Stefan Hello Mitnick, > > asynchronous i/o is also missing in block/vpc.c. > > All newer block drivers support asynchronous reads and writes, > only some old drivers don't. > > So adding asynchronous i/o to at least some of the old drivers > would improve their usability. > > Look for "aio"

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-03-30 Thread Lyu Mitnick
Hello Stefan, Let me summarize the ideas of "Improved image format compatibility" now: (1) add support of "Fixed hard disk image" into block/vpc.c (2) add support of "Differencing hard disk image" into block/vpc.c (3) add asynchronous i/o into block/vpc,c (4) have some optimization of block/vpc.

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-03-30 Thread Stefan Weil
Am 30.03.2011 20:40, schrieb Lyu Mitnick: Hello Stefan, I have spent a whole night to trace the code of block/vpc.c and compare against the VHD specifications (at http://www.microsoft.com/downloads/en/details.aspx?FamilyID=C2D03242-2FFB-48EF-A211-F0C44741109E&displaylang=en

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-03-30 Thread Lyu Mitnick
Hello Stefan, I have spent a whole night to trace the code of block/vpc.c and compare against the VHD specifications (at http://www.microsoft.com/downloads/en/details.aspx?FamilyID=C2D03242-2FFB-48EF-A211-F0C44741109E&displaylang=en ). It seems that there isn't Fixed hard disk image and Differenci

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-03-30 Thread Stefan Hajnoczi
On Wed, Mar 30, 2011 at 5:50 AM, Stefan Weil wrote: > Am 29.03.2011 23:55, schrieb Lyu Mitnick: >> >> Hello all, >> >> I have used QEMU to assist me developing embedded system for 3 years. And >> I >> want to contribute to QEMU and participate Google Summer of Code this >> year. >> I have port bin

Re: [Qemu-devel] GSoC: Improved image format compatibility

2011-03-29 Thread Stefan Weil
Am 29.03.2011 23:55, schrieb Lyu Mitnick: Hello all, I have used QEMU to assist me developing embedded system for 3 years. And I want to contribute to QEMU and participate Google Summer of Code this year. I have port binutils so I have some experienced with binary format. I noticed that there is

[Qemu-devel] GSoC: Improved image format compatibility

2011-03-29 Thread Lyu Mitnick
Hello all, I have used QEMU to assist me developing embedded system for 3 years. And I want to contribute to QEMU and participate Google Summer of Code this year. I have port binutils so I have some experienced with binary format. I noticed that there is no VHD support in qemu-img. A Virtual Hard