On 10-6-1 上午11:23, Joel Fernandes wrote: >> I'm learning block devices in Linux. It seems submit_bio can be used by file >> systems to submit block IO requests. But after I search for it in the linux >> kernel, I didn't see file systems like ext2 and ext3 use it. So how does a file >> system usually submit a request? I didn't find a wrapper of submit_bio or >> generic_make_request can be used either. > > Usually one of the functions defined in buffer_head.h like sb_bread or sb_getblk > is used. The bio structure and its attributes have to be initialized properly and > you usually don't need to do this on your own. Thanks. So the disk cache actually works beneath the file system instead of on the top of it as described in Understanding the Linux Kernel. Zheng Da -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
