f2fs: remove unused GC_FAILURE_PIN

After commit 3db1de0e ("f2fs: change the current atomic write way"),
we removed all GC_FAILURE_ATOMIC usage, let's change i_gc_failures[]
array to i_pin_failure for cleanup.

Meanwhile, let's define i_current_depth and i_gc_failures as union
variable due to they won't be valid at the same time.
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/f2fs.h

@@ -765,11 +765,6 @@ enum {
 
 #define DEF_DIR_LEVEL		0
 
-enum {
-	GC_FAILURE_PIN,
-	MAX_GC_FAILURE
-};
-
 /* used for f2fs_inode_info->flags */
 enum {
 	FI_NEW_INODE,		/* indicate newly allocated inode */
@@ -816,9 +811,10 @@ struct f2fs_inode_info {
 	unsigned long i_flags;		/* keep an inode flags for ioctl */
 	unsigned char i_advise;		/* use to give file attribute hints */
 	unsigned char i_dir_level;	/* use for dentry level for large dir */
-	unsigned int i_current_depth;	/* only for directory depth */
-	/* for gc failure statistic */
-	unsigned int i_gc_failures[MAX_GC_FAILURE];
+	union {
+		unsigned int i_current_depth;	/* only for directory depth */
+		unsigned int i_gc_failures;	/* for gc failure statistic */
+	};
 	unsigned int i_pino;		/* parent inode number */
 	umode_t i_acl_mode;		/* keep file acl mode temporarily */
 
@@ -3133,7 +3129,7 @@ static inline void f2fs_i_depth_write(struct inode *inode, unsigned int depth)
 static inline void f2fs_i_gc_failures_write(struct inode *inode,
 					unsigned int count)
 {
-	F2FS_I(inode)->i_gc_failures[GC_FAILURE_PIN] = count;
+	F2FS_I(inode)->i_gc_failures = count;
 	f2fs_mark_inode_dirty_sync(inode, true);
 }
 

fs/f2fs/file.c

@@ -3217,13 +3217,11 @@ int f2fs_pin_file_control(struct inode *inode, bool inc)
 
 	/* Use i_gc_failures for normal file as a risk signal. */
 	if (inc)
-		f2fs_i_gc_failures_write(inode,
-				fi->i_gc_failures[GC_FAILURE_PIN] + 1);
+		f2fs_i_gc_failures_write(inode, fi->i_gc_failures + 1);
 
-	if (fi->i_gc_failures[GC_FAILURE_PIN] > sbi->gc_pin_file_threshold) {
+	if (fi->i_gc_failures > sbi->gc_pin_file_threshold) {
 		f2fs_warn(sbi, "%s: Enable GC = ino %lx after %x GC trials",
-			  __func__, inode->i_ino,
-			  fi->i_gc_failures[GC_FAILURE_PIN]);
+			  __func__, inode->i_ino, fi->i_gc_failures);
 		clear_inode_flag(inode, FI_PIN_FILE);
 		return -EAGAIN;
 	}
@@ -3287,7 +3285,7 @@ static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
 	}
 
 	set_inode_flag(inode, FI_PIN_FILE);
-	ret = F2FS_I(inode)->i_gc_failures[GC_FAILURE_PIN];
+	ret = F2FS_I(inode)->i_gc_failures;
 done:
 	f2fs_update_time(sbi, REQ_TIME);
 out:
@@ -3302,7 +3300,7 @@ static int f2fs_ioc_get_pin_file(struct file *filp, unsigned long arg)
 	__u32 pin = 0;
 
 	if (is_inode_flag_set(inode, FI_PIN_FILE))
-		pin = F2FS_I(inode)->i_gc_failures[GC_FAILURE_PIN];
+		pin = F2FS_I(inode)->i_gc_failures;
 	return put_user(pin, (u32 __user *)arg);
 }
 

fs/f2fs/inode.c

@@ -415,8 +415,7 @@ static int do_read_inode(struct inode *inode)
 	if (S_ISDIR(inode->i_mode))
 		fi->i_current_depth = le32_to_cpu(ri->i_current_depth);
 	else if (S_ISREG(inode->i_mode))
-		fi->i_gc_failures[GC_FAILURE_PIN] =
-					le16_to_cpu(ri->i_gc_failures);
+		fi->i_gc_failures = le16_to_cpu(ri->i_gc_failures);
 	fi->i_xattr_nid = le32_to_cpu(ri->i_xattr_nid);
 	fi->i_flags = le32_to_cpu(ri->i_flags);
 	if (S_ISREG(inode->i_mode))
@@ -686,8 +685,7 @@ void f2fs_update_inode(struct inode *inode, struct page *node_page)
 		ri->i_current_depth =
 			cpu_to_le32(F2FS_I(inode)->i_current_depth);
 	else if (S_ISREG(inode->i_mode))
-		ri->i_gc_failures =
-			cpu_to_le16(F2FS_I(inode)->i_gc_failures[GC_FAILURE_PIN]);
+		ri->i_gc_failures = cpu_to_le16(F2FS_I(inode)->i_gc_failures);
 	ri->i_xattr_nid = cpu_to_le32(F2FS_I(inode)->i_xattr_nid);
 	ri->i_flags = cpu_to_le32(F2FS_I(inode)->i_flags);
 	ri->i_pino = cpu_to_le32(F2FS_I(inode)->i_pino);

fs/f2fs/recovery.c

@@ -330,8 +330,7 @@ static int recover_inode(struct inode *inode, struct page *page)
 	F2FS_I(inode)->i_advise = raw->i_advise;
 	F2FS_I(inode)->i_flags = le32_to_cpu(raw->i_flags);
 	f2fs_set_inode_flags(inode);
-	F2FS_I(inode)->i_gc_failures[GC_FAILURE_PIN] =
-				le16_to_cpu(raw->i_gc_failures);
+	F2FS_I(inode)->i_gc_failures = le16_to_cpu(raw->i_gc_failures);
 
 	recover_inline_flags(inode, raw);