Merge tag 'f2fs-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've mainly focused on discard, aka unmap, control
  along with fstrim for Android-specific usage model. In addition, we've
  fixed writepage flow which returned EAGAIN previously resulting in EIO
  of fsync(2) due to mapping's error state. In order to avoid old MM bug
  [1], we decided not to use __GFP_ZERO for the mapping for node and
  meta page caches. As always, we've cleaned up many places for future
  fsverity and symbol conflicts.

  Enhancements:
   - do discard/fstrim in lower priority considering fs utilization
   - split large discard commands into smaller ones for better responsiveness
   - add more sanity checks to address syzbot reports
   - add a mount option, fsync_mode=nobarrier, which can reduce # of cache flushes
   - clean up symbol namespace with modified function names
   - be strict on block allocation and IO control in corner cases

  Bug fixes:
   - don't use __GFP_ZERO for mappings
   - fix error reports in writepage to avoid fsync() failure
   - avoid selinux denial on CAP_RESOURCE on resgid/resuid
   - fix some subtle race conditions in GC/atomic writes/shutdown
   - fix overflow bugs in sanity_check_raw_super
   - fix missing bits on get_flags

  Clean-ups:
   - prepare the generic flow for future fsverity integration
   - fix some broken coding standard"

[1] https://lkml.org/lkml/2018/4/8/661

* tag 'f2fs-for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (79 commits)
  f2fs: fix to clear FI_VOLATILE_FILE correctly
  f2fs: let sync node IO interrupt async one
  f2fs: don't change wbc->sync_mode
  f2fs: fix to update mtime correctly
  fs: f2fs: insert space around that ':' and ', '
  fs: f2fs: add missing blank lines after declarations
  fs: f2fs: changed variable type of offset "unsigned" to "loff_t"
  f2fs: clean up symbol namespace
  f2fs: make set_de_type() static
  f2fs: make __f2fs_write_data_pages() static
  f2fs: fix to avoid accessing cross the boundary
  f2fs: fix to let caller retry allocating block address
  disable loading f2fs module on PAGE_SIZE > 4KB
  f2fs: fix error path of move_data_page
  f2fs: don't drop dentry pages after fs shutdown
  f2fs: fix to avoid race during access gc_thread pointer
  f2fs: clean up with clear_radix_tree_dirty_tag
  f2fs: fix to don't trigger writeback during recovery
  f2fs: clear discard_wake earlier
  f2fs: let discard thread wait a little longer if dev is busy
  ...

1 files changed, 18 insertions, 13 deletions

diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 3325d0769723..f18fc82fbe99 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -85,7 +85,7 @@
 	(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & ((sbi)->blocks_per_seg - 1))
 
 #define GET_SEGNO(sbi, blk_addr)					\
-	((((blk_addr) == NULL_ADDR) || ((blk_addr) == NEW_ADDR)) ?	\
+	((!is_valid_blkaddr(blk_addr)) ?			\
 	NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi),			\
 		GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
 #define BLKS_PER_SEC(sbi)					\
@@ -215,6 +215,8 @@ struct segment_allocation {
 #define IS_DUMMY_WRITTEN_PAGE(page)			\
 		(page_private(page) == (unsigned long)DUMMY_WRITTEN_PAGE)
 
+#define MAX_SKIP_ATOMIC_COUNT			16
+
 struct inmem_pages {
 	struct list_head list;
 	struct page *page;
@@ -375,6 +377,7 @@ static inline void seg_info_to_sit_page(struct f2fs_sb_info *sbi,
 	int i;
 
 	raw_sit = (struct f2fs_sit_block *)page_address(page);
+	memset(raw_sit, 0, PAGE_SIZE);
 	for (i = 0; i < end - start; i++) {
 		rs = &raw_sit->entries[i];
 		se = get_seg_entry(sbi, start + i);
@@ -742,12 +745,23 @@ static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start)
 #endif
 }
 
-static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi)
+static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi,
+						bool base_time)
 {
 	struct sit_info *sit_i = SIT_I(sbi);
-	time64_t now = ktime_get_real_seconds();
+	time64_t diff, now = ktime_get_real_seconds();
+
+	if (now >= sit_i->mounted_time)
+		return sit_i->elapsed_time + now - sit_i->mounted_time;
 
-	return sit_i->elapsed_time + now - sit_i->mounted_time;
+	/* system time is set to the past */
+	if (!base_time) {
+		diff = sit_i->mounted_time - now;
+		if (sit_i->elapsed_time >= diff)
+			return sit_i->elapsed_time - diff;
+		return 0;
+	}
+	return sit_i->elapsed_time;
 }
 
 static inline void set_summary(struct f2fs_summary *sum, nid_t nid,
@@ -771,15 +785,6 @@ static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
 				- (base + 1) + type;
 }
 
-static inline bool no_fggc_candidate(struct f2fs_sb_info *sbi,
-						unsigned int secno)
-{
-	if (get_valid_blocks(sbi, GET_SEG_FROM_SEC(sbi, secno), true) >
-						sbi->fggc_threshold)
-		return true;
-	return false;
-}
-
 static inline bool sec_usage_check(struct f2fs_sb_info *sbi, unsigned int secno)
 {
 	if (IS_CURSEC(sbi, secno) || (sbi->cur_victim_sec == secno))