Policy - Foreground GC, LFS and greedy GC mode. Under this policy, f2fs_gc() loops forever to GC as it doesn't have enough free segements to proceed and thus it keeps calling gc_more for the same victim segment. This can happen if the selected victim segment could not be GC'd due to failed blkaddr validity check i.e. is_alive() returns false for the blocks set in current validity map.
Fix this by keeping track of such invalid segments and skip those segments for selection in get_victim_by_default() to avoid endless GC loop under such error scenarios. Signed-off-by: Sahitya Tummala <stumm...@codeaurora.org> --- v2: fix as per Chao's suggestion to handle this error case fs/f2fs/gc.c | 15 ++++++++++++++- fs/f2fs/segment.c | 5 +++++ fs/f2fs/segment.h | 3 +++ 3 files changed, 22 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index 8974672..321a78a 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -382,6 +382,14 @@ static int get_victim_by_default(struct f2fs_sb_info *sbi, nsearched++; } + /* + * skip selecting the invalid segno (that is failed due to block + * validity check failed during GC) to avoid endless GC loop in + * such cases. + */ + if (test_bit(segno, sm->invalid_segmap)) + goto next; + secno = GET_SEC_FROM_SEG(sbi, segno); if (sec_usage_check(sbi, secno)) @@ -975,6 +983,7 @@ static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, int off; int phase = 0; int submitted = 0; + struct sit_info *sit_i = SIT_I(sbi); start_addr = START_BLOCK(sbi, segno); @@ -1008,8 +1017,12 @@ static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, } /* Get an inode by ino with checking validity */ - if (!is_alive(sbi, entry, &dni, start_addr + off, &nofs)) + if (!is_alive(sbi, entry, &dni, start_addr + off, &nofs)) { + if (!test_and_set_bit(segno, sit_i->invalid_segmap)) + f2fs_err(sbi, "invalid blkaddr %u in seg %u is found\n", + start_addr + off, segno); continue; + } if (phase == 2) { f2fs_ra_node_page(sbi, dni.ino); diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index a661ac3..d45a1d3 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -4017,6 +4017,10 @@ static int build_sit_info(struct f2fs_sb_info *sbi) return -ENOMEM; #endif + sit_i->invalid_segmap = f2fs_kvzalloc(sbi, bitmap_size, GFP_KERNEL); + if (!sit_i->invalid_segmap) + return -ENOMEM; + /* init SIT information */ sit_i->s_ops = &default_salloc_ops; @@ -4518,6 +4522,7 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi) #ifdef CONFIG_F2FS_CHECK_FS kvfree(sit_i->sit_bitmap_mir); #endif + kvfree(sit_i->invalid_segmap); kvfree(sit_i); } diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h index b746028..bc5dbe8 100644 --- a/fs/f2fs/segment.h +++ b/fs/f2fs/segment.h @@ -246,6 +246,9 @@ struct sit_info { unsigned long long min_mtime; /* min. modification time */ unsigned long long max_mtime; /* max. modification time */ + /* list of segments to be ignored by GC in case of errors */ + unsigned long *invalid_segmap; + unsigned int last_victim[MAX_GC_POLICY]; /* last victim segment # */ }; -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.