when we started read-caching this inode

start address within vm_mm

cache related bit mask flag

the first byte after end address within vm_mm

file name

parent dir name

the address of buf in user space

how long the cached information is assumed to be valid. We need to revalidate the cached attrs for this inode if jiffies - read_cache_jiffies > attrtimeo.

vm flags

device identifier

inode number