> > Only change in this revision is the fix to the self-discovered > issue in region_chg(). Functional and stress tests passing. > Full changelog below. > > As suggested during the RFC process, tests have been proposed to > libhugetlbfs as described at: > http://librelist.com/browser//libhugetlbfs/2015/6/25/patch-tests-add-tests-for-fallocate-system-call/ > fallocate(2) man page modifications are also necessary to specify > that fallocate for hugetlbfs only operates on whole pages. This > change will be submitted once the code has stabilized and been > proposed for merging. > > hugetlbfs is used today by applications that want a high degree of > control over huge page usage. Often, large hugetlbfs files are used > to map a large number huge pages into the application processes. > The applications know when page ranges within these large files will > no longer be used, and ideally would like to release them back to > the subpool or global pools for other uses. The fallocate() system > call provides an interface for preallocation and hole punching within > files. This patch set adds fallocate functionality to hugetlbfs. > > v3: > Fixed issue with region_chg to recheck if there are sufficient > entries in the cache after acquiring lock. > v2: > Fixed leak in resv_map_release discovered by Hillf Danton. > Used LONG_MAX as indicator of truncate function for region_del. > v1: > Add a cache of region descriptors to the resv_map for use by > region_add in case hole punch deletes entries necessary for > a successful operation. > RFC v4: > Removed alloc_huge_page/hugetlb_reserve_pages race patches as already > in mmotm > Moved hugetlb_fix_reserve_counts in series as suggested by Naoya Horiguchi > Inline'ed hugetlb_fault_mutex routines as suggested by Davidlohr Bueso and > existing code changed to use new interfaces as suggested by Naoya > fallocate preallocation code cleaned up and made simpler > Modified alloc_huge_page to handle special case where allocation is > for a hole punched area with spool reserves > RFC v3: > Folded in patch for alloc_huge_page/hugetlb_reserve_pages race > in current code > fallocate allocation and hole punch is synchronized with page > faults via existing mutex table > hole punch uses existing hugetlb_vmtruncate_list instead of more > generic unmap_mapping_range for unmapping > Error handling for the case when region_del() fauils > RFC v2: > Addressed alignment and error handling issues noticed by Hillf Danton > New region_del() routine for region tracking/resv_map of ranges > Fixed several issues found during more extensive testing > Error handling in region_del() when kmalloc() fails stills needs > to be addressed > madvise remove support remains > > Mike Kravetz (10): > mm/hugetlb: add cache of descriptors to resv_map for region_add > mm/hugetlb: add region_del() to delete a specific range of entries > mm/hugetlb: expose hugetlb fault mutex for use by fallocate > hugetlbfs: hugetlb_vmtruncate_list() needs to take a range to delete > hugetlbfs: truncate_hugepages() takes a range of pages > mm/hugetlb: vma_has_reserves() needs to handle fallocate hole punch > mm/hugetlb: alloc_huge_page handle areas hole punched by fallocate > hugetlbfs: New huge_add_to_page_cache helper routine > hugetlbfs: add hugetlbfs_fallocate() > mm: madvise allow remove operation for hugetlbfs > > fs/hugetlbfs/inode.c | 281 +++++++++++++++++++++++++++++--- > include/linux/hugetlb.h | 17 +- > mm/hugetlb.c | 423 ++++++++++++++++++++++++++++++++++++++---------- > mm/madvise.c | 2 +- > 4 files changed, 619 insertions(+), 104 deletions(-) > Acked-by: Hillf Danton <hillf.zj@xxxxxxxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>