The patch titled Subject: tmpfs: support fallocate FALLOC_FL_PUNCH_HOLE has been added to the -mm tree. Its filename is tmpfs-support-fallocate-falloc_fl_punch_hole.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Hugh Dickins <hughd@xxxxxxxxxx> Subject: tmpfs: support fallocate FALLOC_FL_PUNCH_HOLE tmpfs has supported hole-punching since 2.6.16, via madvise(,,MADV_REMOVE). But nowadays fallocate(,FALLOC_FL_PUNCH_HOLE|FALLOC_FL_KEEP_SIZE,,) is the agreed way to punch holes. So add shmem_fallocate() to support that, and tweak shmem_truncate_range() to support partial pages at both the beginning and end of range (never needed for madvise, which demands rounded addr and rounds up length). Based-on-patch-by: Cong Wang <amwang@xxxxxxxxxx> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Cong Wang <amwang@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/shmem.c | 68 ++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 57 insertions(+), 11 deletions(-) diff -puN mm/shmem.c~tmpfs-support-fallocate-falloc_fl_punch_hole mm/shmem.c --- a/mm/shmem.c~tmpfs-support-fallocate-falloc_fl_punch_hole +++ a/mm/shmem.c @@ -53,6 +53,7 @@ static struct vfsmount *shm_mnt; #include <linux/blkdev.h> #include <linux/pagevec.h> #include <linux/percpu_counter.h> +#include <linux/falloc.h> #include <linux/splice.h> #include <linux/security.h> #include <linux/swapops.h> @@ -432,21 +433,23 @@ void shmem_truncate_range(struct inode * struct address_space *mapping = inode->i_mapping; struct shmem_inode_info *info = SHMEM_I(inode); pgoff_t start = (lstart + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - unsigned partial = lstart & (PAGE_CACHE_SIZE - 1); - pgoff_t end = (lend >> PAGE_CACHE_SHIFT); + pgoff_t end = (lend + 1) >> PAGE_CACHE_SHIFT; + unsigned int partial_start = lstart & (PAGE_CACHE_SIZE - 1); + unsigned int partial_end = (lend + 1) & (PAGE_CACHE_SIZE - 1); struct pagevec pvec; pgoff_t indices[PAGEVEC_SIZE]; long nr_swaps_freed = 0; pgoff_t index; int i; - BUG_ON((lend & (PAGE_CACHE_SIZE - 1)) != (PAGE_CACHE_SIZE - 1)); + if (lend == -1) + end = -1; /* unsigned, so actually very big */ pagevec_init(&pvec, 0); index = start; - while (index <= end) { + while (index < end) { pvec.nr = shmem_find_get_pages_and_swap(mapping, index, - min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1, + min(end - index, (pgoff_t)PAGEVEC_SIZE), pvec.pages, indices); if (!pvec.nr) break; @@ -455,7 +458,7 @@ void shmem_truncate_range(struct inode * struct page *page = pvec.pages[i]; index = indices[i]; - if (index > end) + if (index >= end) break; if (radix_tree_exceptional_entry(page)) { @@ -479,22 +482,39 @@ void shmem_truncate_range(struct inode * index++; } - if (partial) { + if (partial_start) { struct page *page = NULL; shmem_getpage(inode, start - 1, &page, SGP_READ, NULL); if (page) { - zero_user_segment(page, partial, PAGE_CACHE_SIZE); + unsigned int top = PAGE_CACHE_SIZE; + if (start > end) { + top = partial_end; + partial_end = 0; + } + zero_user_segment(page, partial_start, top); set_page_dirty(page); unlock_page(page); page_cache_release(page); } } + if (partial_end) { + struct page *page = NULL; + shmem_getpage(inode, end, &page, SGP_READ, NULL); + if (page) { + zero_user_segment(page, 0, partial_end); + set_page_dirty(page); + unlock_page(page); + page_cache_release(page); + } + } + if (start >= end) + return; index = start; for ( ; ; ) { cond_resched(); pvec.nr = shmem_find_get_pages_and_swap(mapping, index, - min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1, + min(end - index, (pgoff_t)PAGEVEC_SIZE), pvec.pages, indices); if (!pvec.nr) { if (index == start) @@ -502,7 +522,7 @@ void shmem_truncate_range(struct inode * index = start; continue; } - if (index == start && indices[0] > end) { + if (index == start && indices[0] >= end) { shmem_deswap_pagevec(&pvec); pagevec_release(&pvec); break; @@ -512,7 +532,7 @@ void shmem_truncate_range(struct inode * struct page *page = pvec.pages[i]; index = indices[i]; - if (index > end) + if (index >= end) break; if (radix_tree_exceptional_entry(page)) { @@ -1578,6 +1598,31 @@ static ssize_t shmem_file_splice_read(st return error; } +static long shmem_fallocate(struct file *file, int mode, loff_t offset, + loff_t len) +{ + struct inode *inode = file->f_path.dentry->d_inode; + int error = -EOPNOTSUPP; + + mutex_lock(&inode->i_mutex); + + if (mode & FALLOC_FL_PUNCH_HOLE) { + struct address_space *mapping = file->f_mapping; + loff_t unmap_start = round_up(offset, PAGE_SIZE); + loff_t unmap_end = round_down(offset + len, PAGE_SIZE) - 1; + + if ((u64)unmap_end > (u64)unmap_start) + unmap_mapping_range(mapping, unmap_start, + 1 + unmap_end - unmap_start, 0); + shmem_truncate_range(inode, offset, offset + len - 1); + /* No need to unmap again: hole-punching leaves COWed pages */ + error = 0; + } + + mutex_unlock(&inode->i_mutex); + return error; +} + static int shmem_statfs(struct dentry *dentry, struct kstatfs *buf) { struct shmem_sb_info *sbinfo = SHMEM_SB(dentry->d_sb); @@ -2478,6 +2523,7 @@ static const struct file_operations shme .fsync = noop_fsync, .splice_read = shmem_file_splice_read, .splice_write = generic_file_splice_write, + .fallocate = shmem_fallocate, #endif }; _ Subject: Subject: tmpfs: support fallocate FALLOC_FL_PUNCH_HOLE Patches currently in -mm which might be from hughd@xxxxxxxxxx are linux-next.patch mm-remove-swap-token-code.patch mm-vmscan-remove-lumpy-reclaim.patch mm-vmscan-do-not-stall-on-writeback-during-memory-compaction.patch mm-vmscan-remove-reclaim_mode_t.patch mm-mmapc-find_vma-remove-unnecessary-ifmm-check.patch mm-mmapc-find_vma-remove-unnecessary-ifmm-check-fix.patch mm-fork-fix-overflow-in-vma-length-when-copying-mmap-on-clone.patch mm-correctly-synchronize-rss-counters-at-exit-exec.patch bug-introduce-build_bug_on_invalid-macro.patch bug-completely-remove-code-generated-by-disabled-vm_bug_on.patch shmem-replace-page-if-mapping-excludes-its-zone.patch tmpfs-enable-nosec-optimization.patch tmpfs-optimize-clearing-when-writing.patch tmpfs-support-fallocate-falloc_fl_punch_hole.patch mm-fs-route-madv_remove-to-falloc_fl_punch_hole.patch mm-fs-remove-truncate_range.patch tmpfs-support-fallocate-preallocation.patch tmpfs-undo-fallocation-on-failure.patch tmpfs-quit-when-fallocate-fills-memory.patch tmpfs-support-seek_data-and-seek_hole.patch memcg-fix-change-behavior-of-shared-anon-at-moving-task.patch memcg-swap-mem_cgroup_move_swap_account-never-needs-fixup.patch memcg-swap-use-mem_cgroup_uncharge_swap.patch mm-memcg-scanning_global_lru-means-mem_cgroup_disabled.patch mm-memcg-move-reclaim_stat-into-lruvec.patch mm-push-lru-index-into-shrink_active_list.patch mm-push-lru-index-into-shrink_active_list-fix.patch mm-mark-mm-inline-functions-as-__always_inline.patch mm-remove-lru-type-checks-from-__isolate_lru_page.patch mm-memcg-kill-mem_cgroup_lru_del.patch mm-memcg-use-vm_swappiness-from-target-memory-cgroup.patch memcg-add-mlock-statistic-in-memorystat.patch memcg-add-mlock-statistic-in-memorystat-fix.patch mm-vmscan-store-priority-in-struct-scan_control.patch mm-add-link-from-struct-lruvec-to-struct-zone.patch mm-vmscan-push-lruvec-pointer-into-isolate_lru_pages.patch mm-vmscan-push-zone-pointer-into-shrink_page_list.patch mm-vmscan-remove-update_isolated_counts.patch mm-vmscan-push-lruvec-pointer-into-putback_inactive_pages.patch mm-vmscan-replace-zone_nr_lru_pages-with-get_lruvec_size.patch mm-vmscan-push-lruvec-pointer-into-inactive_list_is_low.patch mm-vmscan-push-lruvec-pointer-into-shrink_list.patch mm-vmscan-push-lruvec-pointer-into-get_scan_count.patch mm-vmscan-push-lruvec-pointer-into-should_continue_reclaim.patch mm-vmscan-kill-struct-mem_cgroup_zone.patch mm-huge_memoryc-use-lockdep_assert_held.patch proc-clean-up-proc-pid-environ-handling.patch proc-remove-mm_for_maps.patch proc-use-mm_access-instead-of-ptrace_may_access.patch proc-report-file-anon-bit-in-proc-pid-pagemap.patch proc-use-is_err_or_null.patch fork-call-complete_vfork_done-after-clearing-child_tid-and-flushing-rss-counters.patch prio_tree-debugging-patch.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html