From ae27d62e6befd3cac4ffa702e644cc52019642e8 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Sat, 7 Jan 2017 18:52:34 +0800 Subject: [PATCH] f2fs: check in-memory sit version bitmap This patch adds a mirror for sit version bitmap, and use it to detect in-memory bitmap corruption which may be caused by bit-transition of cache or memory overflow. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/segment.c | 16 ++++++++++++---- fs/f2fs/segment.h | 18 ++++++++++++++++++ 2 files changed, 30 insertions(+), 4 deletions(-) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 56a097d..c8c8255 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -2346,7 +2346,7 @@ static int build_sit_info(struct f2fs_sb_info *sbi) struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi); struct sit_info *sit_i; unsigned int sit_segs, start; - char *src_bitmap, *dst_bitmap; + char *src_bitmap; unsigned int bitmap_size; /* allocate memory for SIT information */ @@ -2408,17 +2408,22 @@ static int build_sit_info(struct f2fs_sb_info *sbi) bitmap_size = __bitmap_size(sbi, SIT_BITMAP); src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP); - dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL); - if (!dst_bitmap) + sit_i->sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL); + if (!sit_i->sit_bitmap) return -ENOMEM; +#ifdef CONFIG_F2FS_CHECK_FS + sit_i->sit_bitmap_mir = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL); + if (!sit_i->sit_bitmap_mir) + return -ENOMEM; +#endif + /* init SIT information */ sit_i->s_ops = &default_salloc_ops; sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr); sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg; sit_i->written_valid_blocks = 0; - sit_i->sit_bitmap = dst_bitmap; sit_i->bitmap_size = bitmap_size; sit_i->dirty_sentries = 0; sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK; @@ -2826,6 +2831,9 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi) SM_I(sbi)->sit_info = NULL; kfree(sit_i->sit_bitmap); +#ifdef CONFIG_F2FS_CHECK_FS + kfree(sit_i->sit_bitmap_mir); +#endif kfree(sit_i); } diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index 9af9519..5cb5755 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -209,6 +209,9 @@ struct sit_info { block_t sit_blocks; /* # of blocks used by SIT area */ block_t written_valid_blocks; /* # of valid blocks in main area */ char *sit_bitmap; /* SIT bitmap pointer */ +#ifdef CONFIG_F2FS_CHECK_FS + char *sit_bitmap_mir; /* SIT bitmap mirror */ +#endif unsigned int bitmap_size; /* SIT bitmap size */ unsigned long *tmp_map; /* bitmap for temporal use */ @@ -423,6 +426,12 @@ static inline void get_sit_bitmap(struct f2fs_sb_info *sbi, void *dst_addr) { struct sit_info *sit_i = SIT_I(sbi); + +#ifdef CONFIG_F2FS_CHECK_FS + if (memcmp(sit_i->sit_bitmap, sit_i->sit_bitmap_mir, + sit_i->bitmap_size)) + f2fs_bug_on(sbi, 1); +#endif memcpy(dst_addr, sit_i->sit_bitmap, sit_i->bitmap_size); } @@ -643,6 +652,12 @@ static inline pgoff_t current_sit_addr(struct f2fs_sb_info *sbi, check_seg_range(sbi, start); +#ifdef CONFIG_F2FS_CHECK_FS + if (f2fs_test_bit(offset, sit_i->sit_bitmap) != + f2fs_test_bit(offset, sit_i->sit_bitmap_mir)) + f2fs_bug_on(sbi, 1); +#endif + /* calculate sit block address */ if (f2fs_test_bit(offset, sit_i->sit_bitmap)) blk_addr += sit_i->sit_blocks; @@ -668,6 +683,9 @@ static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start) unsigned int block_off = SIT_BLOCK_OFFSET(start); f2fs_change_bit(block_off, sit_i->sit_bitmap); +#ifdef CONFIG_F2FS_CHECK_FS + f2fs_change_bit(block_off, sit_i->sit_bitmap_mir); +#endif } static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi) -- 2.7.4