On Thu, Jun 11, 2020 at 05:46:43PM -0700, Mike Kravetz wrote: > The routine is_file_hugepages() checks f_op == hugetlbfs_file_operations > to determine if the file resides in hugetlbfs. This is problematic when > the file is on a union or overlay. Instead, define a new file mode > FMODE_HUGETLBFS which is set when a hugetlbfs file is opened. The mode > can easily be copied to other 'files' derived from the original hugetlbfs > file. > > With this change hugetlbfs_file_operations can be static as it should be. > > There is also a (duplicate) set of shm file operations used for the routine > is_file_shm_hugepages(). Instead of setting/using special f_op's, just > propagate the FMODE_HUGETLBFS mode. This means is_file_shm_hugepages() and > the duplicate f_ops can be removed. s/HUGETLBFS/HUGEPAGES/, please. > While cleaning things up, change the name of is_file_hugepages() to > is_file_hugetlbfs(). The term hugepages is a bit ambiguous. Don't, especially since the very next patch adds such on overlayfs... Incidentally, can a hugetlbfs be a lower layer, while the upper one is a normal filesystem? What should happen on copyup?
