f2fs: Add f2fs stats to sysfs

Currently f2fs stats are only available from /d/f2fs/status. This patch
adds some of the f2fs stats to sysfs so that they are accessible even
when debugfs is not mounted.

The following sysfs nodes are added:
-/sys/fs/f2fs/<disk>/free_segments
-/sys/fs/f2fs/<disk>/cp_foreground_calls
-/sys/fs/f2fs/<disk>/cp_background_calls
-/sys/fs/f2fs/<disk>/gc_foreground_calls
-/sys/fs/f2fs/<disk>/gc_background_calls
-/sys/fs/f2fs/<disk>/moved_blocks_foreground
-/sys/fs/f2fs/<disk>/moved_blocks_background
-/sys/fs/f2fs/<disk>/avg_vblocks

Signed-off-by: Hridya Valsaraju <hridya@google.com>
[Jaegeuk Kim: allow STAT_FS without DEBUG_FS]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 107 insertions, 32 deletions

diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 5152a7487335..91d649790b1b 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -25,6 +25,9 @@ enum {
 	DCC_INFO,	/* struct discard_cmd_control */
 	NM_INFO,	/* struct f2fs_nm_info */
 	F2FS_SBI,	/* struct f2fs_sb_info */
+#ifdef CONFIG_F2FS_STAT_FS
+	STAT_INFO,      /* struct f2fs_stat_info */
+#endif
 #ifdef CONFIG_F2FS_FAULT_INJECTION
 	FAULT_INFO_RATE,	/* struct f2fs_fault_info */
 	FAULT_INFO_TYPE,	/* struct f2fs_fault_info */
@@ -42,6 +45,9 @@ struct f2fs_attr {
 	int id;
 };
 
+static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
+			     struct f2fs_sb_info *sbi, char *buf);
+
 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
 {
 	if (struct_type == GC_THREAD)
@@ -59,41 +65,25 @@ static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
 					struct_type == FAULT_INFO_TYPE)
 		return (unsigned char *)&F2FS_OPTION(sbi).fault_info;
 #endif
+#ifdef CONFIG_F2FS_STAT_FS
+	else if (struct_type == STAT_INFO)
+		return (unsigned char *)F2FS_STAT(sbi);
+#endif
 	return NULL;
 }
 
 static ssize_t dirty_segments_show(struct f2fs_attr *a,
 		struct f2fs_sb_info *sbi, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
-		(unsigned long long)(dirty_segments(sbi)));
+	return sprintf(buf, "%llu\n",
+			(unsigned long long)(dirty_segments(sbi)));
 }
 
-static ssize_t unusable_show(struct f2fs_attr *a,
+static ssize_t free_segments_show(struct f2fs_attr *a,
 		struct f2fs_sb_info *sbi, char *buf)
 {
-	block_t unusable;
-
-	if (test_opt(sbi, DISABLE_CHECKPOINT))
-		unusable = sbi->unusable_block_count;
-	else
-		unusable = f2fs_get_unusable_blocks(sbi);
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
-		(unsigned long long)unusable);
-}
-
-static ssize_t encoding_show(struct f2fs_attr *a,
-		struct f2fs_sb_info *sbi, char *buf)
-{
-#ifdef CONFIG_UNICODE
-	if (f2fs_sb_has_casefold(sbi))
-		return snprintf(buf, PAGE_SIZE, "%s (%d.%d.%d)\n",
-			sbi->s_encoding->charset,
-			(sbi->s_encoding->version >> 16) & 0xff,
-			(sbi->s_encoding->version >> 8) & 0xff,
-			sbi->s_encoding->version & 0xff);
-#endif
-	return snprintf(buf, PAGE_SIZE, "(none)");
+	return sprintf(buf, "%llu\n",
+			(unsigned long long)(free_segments(sbi)));
 }
 
 static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
@@ -102,10 +92,10 @@ static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
 	struct super_block *sb = sbi->sb;
 
 	if (!sb->s_bdev->bd_part)
-		return snprintf(buf, PAGE_SIZE, "0\n");
+		return sprintf(buf, "0\n");
 
-	return snprintf(buf, PAGE_SIZE, "%llu\n",
-		(unsigned long long)(sbi->kbytes_written +
+	return sprintf(buf, "%llu\n",
+			(unsigned long long)(sbi->kbytes_written +
 			BD_PART_WRITTEN(sbi)));
 }
 
@@ -116,7 +106,7 @@ static ssize_t features_show(struct f2fs_attr *a,
 	int len = 0;
 
 	if (!sb->s_bdev->bd_part)
-		return snprintf(buf, PAGE_SIZE, "0\n");
+		return sprintf(buf, "0\n");
 
 	if (f2fs_sb_has_encrypt(sbi))
 		len += snprintf(buf, PAGE_SIZE - len, "%s",
@@ -166,9 +156,66 @@ static ssize_t features_show(struct f2fs_attr *a,
 static ssize_t current_reserved_blocks_show(struct f2fs_attr *a,
 					struct f2fs_sb_info *sbi, char *buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%u\n", sbi->current_reserved_blocks);
+	return sprintf(buf, "%u\n", sbi->current_reserved_blocks);
+}
+
+static ssize_t unusable_show(struct f2fs_attr *a,
+		struct f2fs_sb_info *sbi, char *buf)
+{
+	block_t unusable;
+
+	if (test_opt(sbi, DISABLE_CHECKPOINT))
+		unusable = sbi->unusable_block_count;
+	else
+		unusable = f2fs_get_unusable_blocks(sbi);
+	return sprintf(buf, "%llu\n", (unsigned long long)unusable);
 }
 
+static ssize_t encoding_show(struct f2fs_attr *a,
+		struct f2fs_sb_info *sbi, char *buf)
+{
+#ifdef CONFIG_UNICODE
+	if (f2fs_sb_has_casefold(sbi))
+		return snprintf(buf, PAGE_SIZE, "%s (%d.%d.%d)\n",
+			sbi->s_encoding->charset,
+			(sbi->s_encoding->version >> 16) & 0xff,
+			(sbi->s_encoding->version >> 8) & 0xff,
+			sbi->s_encoding->version & 0xff);
+#endif
+	return sprintf(buf, "(none)");
+}
+
+#ifdef CONFIG_F2FS_STAT_FS
+static ssize_t moved_blocks_foreground_show(struct f2fs_attr *a,
+				struct f2fs_sb_info *sbi, char *buf)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+
+	return sprintf(buf, "%llu\n",
+		(unsigned long long)(si->tot_blks -
+			(si->bg_data_blks + si->bg_node_blks)));
+}
+
+static ssize_t moved_blocks_background_show(struct f2fs_attr *a,
+				struct f2fs_sb_info *sbi, char *buf)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+
+	return sprintf(buf, "%llu\n",
+		(unsigned long long)(si->bg_data_blks + si->bg_node_blks));
+}
+
+static ssize_t avg_vblocks_show(struct f2fs_attr *a,
+		struct f2fs_sb_info *sbi, char *buf)
+{
+	struct f2fs_stat_info *si = F2FS_STAT(sbi);
+
+	si->dirty_count = dirty_segments(sbi);
+	f2fs_update_sit_info(sbi);
+	return sprintf(buf, "%llu\n", (unsigned long long)(si->avg_vblocks));
+}
+#endif
+
 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 			struct f2fs_sb_info *sbi, char *buf)
 {
@@ -202,7 +249,7 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
 
 	ui = (unsigned int *)(ptr + a->offset);
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
+	return sprintf(buf, "%u\n", *ui);
 }
 
 static ssize_t __sbi_store(struct f2fs_attr *a,
@@ -413,7 +460,7 @@ static ssize_t f2fs_feature_show(struct f2fs_attr *a,
 	case FEAT_SB_CHECKSUM:
 	case FEAT_CASEFOLD:
 	case FEAT_COMPRESSION:
-		return snprintf(buf, PAGE_SIZE, "supported\n");
+		return sprintf(buf, "supported\n");
 	}
 	return 0;
 }
@@ -442,6 +489,14 @@ static struct f2fs_attr f2fs_attr_##_name = {			\
 	.id	= _id,						\
 }
 
+#define F2FS_STAT_ATTR(_struct_type, _struct_name, _name, _elname)	\
+static struct f2fs_attr f2fs_attr_##_name = {			\
+	.attr = {.name = __stringify(_name), .mode = 0444 },	\
+	.show = f2fs_sbi_show,					\
+	.struct_type = _struct_type,				\
+	.offset = offsetof(struct _struct_name, _elname),       \
+}
+
 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_urgent_sleep_time,
 							urgent_sleep_time);
 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
@@ -483,11 +538,21 @@ F2FS_RW_ATTR(FAULT_INFO_RATE, f2fs_fault_info, inject_rate, inject_rate);
 F2FS_RW_ATTR(FAULT_INFO_TYPE, f2fs_fault_info, inject_type, inject_type);
 #endif
 F2FS_GENERAL_RO_ATTR(dirty_segments);
+F2FS_GENERAL_RO_ATTR(free_segments);
 F2FS_GENERAL_RO_ATTR(lifetime_write_kbytes);
 F2FS_GENERAL_RO_ATTR(features);
 F2FS_GENERAL_RO_ATTR(current_reserved_blocks);
 F2FS_GENERAL_RO_ATTR(unusable);
 F2FS_GENERAL_RO_ATTR(encoding);
+#ifdef CONFIG_F2FS_STAT_FS
+F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_foreground_calls, cp_count);
+F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, cp_background_calls, bg_cp_count);
+F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, gc_foreground_calls, call_count);
+F2FS_STAT_ATTR(STAT_INFO, f2fs_stat_info, gc_background_calls, bg_gc);
+F2FS_GENERAL_RO_ATTR(moved_blocks_background);
+F2FS_GENERAL_RO_ATTR(moved_blocks_foreground);
+F2FS_GENERAL_RO_ATTR(avg_vblocks);
+#endif
 
 #ifdef CONFIG_FS_ENCRYPTION
 F2FS_FEATURE_RO_ATTR(encryption, FEAT_CRYPTO);
@@ -549,12 +614,22 @@ static struct attribute *f2fs_attrs[] = {
 	ATTR_LIST(inject_type),
 #endif
 	ATTR_LIST(dirty_segments),
+	ATTR_LIST(free_segments),
 	ATTR_LIST(unusable),
 	ATTR_LIST(lifetime_write_kbytes),
 	ATTR_LIST(features),
 	ATTR_LIST(reserved_blocks),
 	ATTR_LIST(current_reserved_blocks),
 	ATTR_LIST(encoding),
+#ifdef CONFIG_F2FS_STAT_FS
+	ATTR_LIST(cp_foreground_calls),
+	ATTR_LIST(cp_background_calls),
+	ATTR_LIST(gc_foreground_calls),
+	ATTR_LIST(gc_background_calls),
+	ATTR_LIST(moved_blocks_foreground),
+	ATTR_LIST(moved_blocks_background),
+	ATTR_LIST(avg_vblocks),
+#endif
 	NULL,
 };
 ATTRIBUTE_GROUPS(f2fs);