From 3db1de0e582c358dd013f3703cd55b5fe4076436 Mon Sep 17 00:00:00 2001 From: Daeho Jeong Date: Thu, 28 Apr 2022 11:18:09 -0700 Subject: f2fs: change the current atomic write way Current atomic write has three major issues like below. - keeps the updates in non-reclaimable memory space and they are even hard to be migrated, which is not good for contiguous memory allocation. - disk spaces used for atomic files cannot be garbage collected, so this makes it difficult for the filesystem to be defragmented. - If atomic write operations hit the threshold of either memory usage or garbage collection failure count, All the atomic write operations will fail immediately. To resolve the issues, I will keep a COW inode internally for all the updates to be flushed from memory, when we need to flush them out in a situation like high memory pressure. These COW inodes will be tagged as orphan inodes to be reclaimed in case of sudden power-cut or system failure during atomic writes. Signed-off-by: Daeho Jeong Signed-off-by: Jaegeuk Kim --- fs/f2fs/segment.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/f2fs/segment.h') diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 8fbc9f6afa55..3f277dfcb131 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -225,10 +225,10 @@ struct segment_allocation { #define MAX_SKIP_GC_COUNT 16 -struct inmem_pages { +struct revoke_entry { struct list_head list; - struct page *page; block_t old_addr; /* for revoking when fail to commit */ + pgoff_t index; }; struct sit_info { -- cgit v1.2.3-58-ga151