Merge tag 'f2fs-for-5.7-rc1' 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 fixing bugs and addressing
  issues in recently introduced compression support.

  Enhancement:
   - add zstd support, and set LZ4 by default
   - add ioctl() to show # of compressed blocks
   - show mount time in debugfs
   - replace rwsem with spinlock
   - avoid lock contention in DIO reads

  Some major bug fixes wrt compression:
   - compressed block count
   - memory access and leak
   - remove obsolete fields
   - flag controls

  Other bug fixes and clean ups:
   - fix overflow when handling .flags in inode_info
   - fix SPO issue during resize FS flow
   - fix compression with fsverity enabled
   - potential deadlock when writing compressed pages
   - show missing mount options"

* tag 'f2fs-for-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (66 commits)
  f2fs: keep inline_data when compression conversion
  f2fs: fix to disable compression on directory
  f2fs: add missing CONFIG_F2FS_FS_COMPRESSION
  f2fs: switch discard_policy.timeout to bool type
  f2fs: fix to verify tpage before releasing in f2fs_free_dic()
  f2fs: show compression in statx
  f2fs: clean up dic->tpages assignment
  f2fs: compress: support zstd compress algorithm
  f2fs: compress: add .{init,destroy}_decompress_ctx callback
  f2fs: compress: fix to call missing destroy_compress_ctx()
  f2fs: change default compression algorithm
  f2fs: clean up {cic,dic}.ref handling
  f2fs: fix to use f2fs_readpage_limit() in f2fs_read_multi_pages()
  f2fs: xattr.h: Make stub helpers inline
  f2fs: fix to avoid double unlock
  f2fs: fix potential .flags overflow on 32bit architecture
  f2fs: fix NULL pointer dereference in f2fs_verity_work()
  f2fs: fix to clear PG_error if fsverity failed
  f2fs: don't call fscrypt_get_encryption_info() explicitly in f2fs_tmpfile()
  f2fs: don't trigger data flush in foreground operation
  ...

Author: torvalds

Documentation/ABI/testing/sysfs-fs-f2fs

@@ -318,3 +318,8 @@ Date:		September 2019
 Contact:	"Hridya Valsaraju" <[email protected]>
 Description:	Average number of valid blocks.
 		Available when CONFIG_F2FS_STAT_FS=y.
+
+What:		/sys/fs/f2fs/<disk>/mounted_time_sec
+Date:		February 2020
+Contact:	"Jaegeuk Kim" <[email protected]>
+Description:	Show the mounted time in secs of this partition.

Documentation/filesystems/f2fs.rst

@@ -243,8 +243,8 @@ checkpoint=%s[:%u[%]]  Set to "disable" to turn off checkpointing. Set to "enabl
                        hide up to all remaining free space. The actual space that
                        would be unusable can be viewed at /sys/fs/f2fs/<disk>/unusable
                        This space is reclaimed once checkpoint=enable.
-compress_algorithm=%s  Control compress algorithm, currently f2fs supports "lzo"
-                       and "lz4" algorithm.
+compress_algorithm=%s  Control compress algorithm, currently f2fs supports "lzo",
+                       "lz4" and "zstd" algorithm.
 compress_log_size=%u   Support configuring compress cluster size, the size will
                        be 4KB * (1 << %u), 16KB is minimum size, also it's
                        default size.

fs/f2fs/Kconfig

@@ -118,3 +118,12 @@ config F2FS_FS_LZ4
 	default y
 	help
 	  Support LZ4 compress algorithm, if unsure, say Y.
+
+config F2FS_FS_ZSTD
+	bool "ZSTD compression support"
+	depends on F2FS_FS_COMPRESSION
+	select ZSTD_COMPRESS
+	select ZSTD_DECOMPRESS
+	default y
+	help
+	  Support ZSTD compress algorithm, if unsure, say Y.

fs/f2fs/checkpoint.c

@@ -50,9 +50,6 @@ struct page *f2fs_grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
 	return page;
 }
 
-/*
- * We guarantee no failure on the returned page.
- */
 static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
 							bool is_meta)
 {
@@ -206,7 +203,7 @@ bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi,
 }
 
 /*
- * Readahead CP/NAT/SIT/SSA pages
+ * Readahead CP/NAT/SIT/SSA/POR pages
  */
 int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
 							int type, bool sync)
@@ -898,7 +895,7 @@ int f2fs_get_valid_checkpoint(struct f2fs_sb_info *sbi)
 		return -ENOMEM;
 	/*
 	 * Finding out valid cp block involves read both
-	 * sets( cp pack1 and cp pack 2)
+	 * sets( cp pack 1 and cp pack 2)
 	 */
 	cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
 	cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
@@ -1250,20 +1247,20 @@ static void unblock_operations(struct f2fs_sb_info *sbi)
 	f2fs_unlock_all(sbi);
 }
 
-void f2fs_wait_on_all_pages_writeback(struct f2fs_sb_info *sbi)
+void f2fs_wait_on_all_pages(struct f2fs_sb_info *sbi, int type)
 {
 	DEFINE_WAIT(wait);
 
 	for (;;) {
 		prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
 
-		if (!get_pages(sbi, F2FS_WB_CP_DATA))
+		if (!get_pages(sbi, type))
 			break;
 
 		if (unlikely(f2fs_cp_error(sbi)))
 			break;
 
-		io_schedule_timeout(5*HZ);
+		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
 	}
 	finish_wait(&sbi->cp_wait, &wait);
 }
@@ -1301,10 +1298,14 @@ static void update_ckpt_flags(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	else
 		__clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
 
-	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK) ||
-		is_sbi_flag_set(sbi, SBI_IS_RESIZEFS))
+	if (is_sbi_flag_set(sbi, SBI_NEED_FSCK))
 		__set_ckpt_flags(ckpt, CP_FSCK_FLAG);
 
+	if (is_sbi_flag_set(sbi, SBI_IS_RESIZEFS))
+		__set_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
+	else
+		__clear_ckpt_flags(ckpt, CP_RESIZEFS_FLAG);
+
 	if (is_sbi_flag_set(sbi, SBI_CP_DISABLED))
 		__set_ckpt_flags(ckpt, CP_DISABLED_FLAG);
 	else
@@ -1384,13 +1385,8 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	/* Flush all the NAT/SIT pages */
 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
-	f2fs_bug_on(sbi, get_pages(sbi, F2FS_DIRTY_META) &&
-					!f2fs_cp_error(sbi));
 
-	/*
-	 * modify checkpoint
-	 * version number is already updated
-	 */
+	/* start to update checkpoint, cp ver is already updated previously */
 	ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi, true));
 	ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
 	for (i = 0; i < NR_CURSEG_NODE_TYPE; i++) {
@@ -1493,11 +1489,11 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	/* Here, we have one bio having CP pack except cp pack 2 page */
 	f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
-	f2fs_bug_on(sbi, get_pages(sbi, F2FS_DIRTY_META) &&
-					!f2fs_cp_error(sbi));
+	/* Wait for all dirty meta pages to be submitted for IO */
+	f2fs_wait_on_all_pages(sbi, F2FS_DIRTY_META);
 
 	/* wait for previous submitted meta pages writeback */
-	f2fs_wait_on_all_pages_writeback(sbi);
+	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
 
 	/* flush all device cache */
 	err = f2fs_flush_device_cache(sbi);
@@ -1506,7 +1502,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	/* barrier and flush checkpoint cp pack 2 page if it can */
 	commit_checkpoint(sbi, ckpt, start_blk);
-	f2fs_wait_on_all_pages_writeback(sbi);
+	f2fs_wait_on_all_pages(sbi, F2FS_WB_CP_DATA);
 
 	/*
 	 * invalidate intermediate page cache borrowed from meta inode which are
@@ -1543,9 +1539,6 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	return unlikely(f2fs_cp_error(sbi)) ? -EIO : 0;
 }
 
-/*
- * We guarantee that this checkpoint procedure will not fail.
- */
 int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 {
 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
@@ -1613,7 +1606,6 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	f2fs_flush_sit_entries(sbi, cpc);
 
-	/* unlock all the fs_lock[] in do_checkpoint() */
 	err = do_checkpoint(sbi, cpc);
 	if (err)
 		f2fs_release_discard_addrs(sbi);
@@ -1626,7 +1618,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 	if (cpc->reason & CP_RECOVERY)
 		f2fs_notice(sbi, "checkpoint: version = %llx", ckpt_ver);
 
-	/* do checkpoint periodically */
+	/* update CP_TIME to trigger checkpoint periodically */
 	f2fs_update_time(sbi, CP_TIME);
 	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint");
 out: