How can I access the special disk sector in kernel?

Hi,Everybody, I want to read a special sector from my disk in kernel, how can I do? For example: I want to read the 48th sector in ad0. in kernel space, if I use the 'open' , 'lseek' , 'read' and 'close', it is wrong! So I do not know how to do. Thank you! Best Regards Ouyang Kai __

How can I access the special disk sector in kernel?

Hi,Everybody, I want to read a special sector from my disk in kernel, how can I do? For example: I want to read the 48th sector in ad0. in kernel space, if I use the 'open' , 'lseek' , 'read' and 'close', it is wrong! So I do not know how to do. Thank you! Best Regards Ouyang Kai __

One GNU ASM syntax problem

Hi,everybody, I have one question about GNU ASM syntax. As I know: __asm __volatile( "instructions" :output :input :exception); In Linux, the restriction of output are "=m","=a", etc. But I found in FreeBSD, there are "=m" and "+m". I do not know the difference between "+" and "=". why?

Re: One GNU ASM syntax problem

I do not know the difference between "+" and "=". why? Thank you, I got it from 'info gcc'. It is the reason that "Extended asm supports input-output or read-write operands. Use the constraint character `+' to indicate such an operand and list it with the output operands.". Best Regards Ouyang K

One Filesystem vnode operations declare problem.

Hi, everybody, I have some questions about FS vnode operations. I found the filesystems always declare vnode operations by "VNODEOP_SET" more than once. For example: In DEVFS: VNODEOP_SET(devfs_vnodeop_opv_desc); VNODEOP_SET(devfs_specop_opv_desc); In FFS: VNODEOP_SET(ffs_vnodeop_opv_