From 7018ec68f08249de17cb131b324d5a48e89ed898 Mon Sep 17 00:00:00 2001

From: Tetsuhiro Kohada <kohada.t2@gmail.com>

Date: Fri, 31 Jul 2020 14:58:26 +0900

Subject: [Backport 7018ec68f082] exfat: retain 'VolumeFlags' properly

MediaFailure and VolumeDirty should be retained if these are set before

mounting.

In '3.1.13.3 Media Failure Field' of exfat specification describe:

 If, upon mounting a volume, the value of this field is 1,

 implementations which scan the entire volume for media failures and

 record all failures as "bad" clusters in the FAT (or otherwise resolve

 media failures) may clear the value of  this field to 0.

Therefore, We should not clear MediaFailure without scanning volume.

In '8.1 Recommended Write Ordering' of exfat specification describe:

 Clear the value of the VolumeDirty field to 0, if its value prior to

 the first step was 0.

Therefore, We should not clear VolumeDirty after mounting.

Also rename ERR_MEDIUM to MEDIA_FAILURE.

Signed-off-by: Tetsuhiro Kohada <kohada.t2@gmail.com>

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

---

 src/exfat_fs.h  |  6 ++++--

 src/exfat_raw.h |  5 ++---

 src/file.c      |  4 ++--

 src/inode.c     |  4 ++--

 src/namei.c     | 20 ++++++++++----------

 src/super.c     | 36 +++++++++++++++++++++++++++---------

 6 files changed, 47 insertions(+), 28 deletions(-)

diff --git a/src/exfat_fs.h b/src/exfat_fs.h

index cb51d6e831990f13413267f4fa0a04c3a6176380..95d717f8620cd06cd29909ca07a17208dfd12325 100644

--- a/src/exfat_fs.h

+++ b/src/exfat_fs.h

@@ -224,7 +224,8 @@ struct exfat_sb_info {

 	unsigned int num_FAT_sectors; /* num of FAT sectors */

 	unsigned int root_dir; /* root dir cluster */

 	unsigned int dentries_per_clu; /* num of dentries per cluster */

-	unsigned int vol_flag; /* volume dirty flag */

+	unsigned int vol_flags; /* volume flags */

+	unsigned int vol_flags_persistent; /* volume flags to retain */

 	struct buffer_head *boot_bh; /* buffer_head of BOOT sector */

 	unsigned int map_clu; /* allocation bitmap start cluster */

@@ -380,7 +381,8 @@ static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,

 }

 /* super.c */

-int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag);

+int exfat_set_volume_dirty(struct super_block *sb);

+int exfat_clear_volume_dirty(struct super_block *sb);

 /* fatent.c */

 #define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu)

diff --git a/src/exfat_raw.h b/src/exfat_raw.h

index 350ce59cc32478919d9ffb9823726b8b9015de48..6aec6288e1f21981920f802083d591034c3fb6a2 100644

--- a/src/exfat_raw.h

+++ b/src/exfat_raw.h

@@ -14,9 +14,8 @@

 #define EXFAT_MAX_FILE_LEN	255

-#define VOL_CLEAN		0x0000

-#define VOL_DIRTY		0x0002

-#define ERR_MEDIUM		0x0004

+#define VOLUME_DIRTY		0x0002

+#define MEDIA_FAILURE		0x0004

 #define EXFAT_EOF_CLUSTER	0xFFFFFFFFu

 #define EXFAT_BAD_CLUSTER	0xFFFFFFF7u

diff --git a/src/file.c b/src/file.c

index 6bdabfd4b13426a1965a0e90598a3f5a2821bbe9..f41f523a58ad4dab6f7c4d3edef6efce21348ce5 100644

--- a/src/file.c

+++ b/src/file.c

@@ -106,7 +106,7 @@ int __exfat_truncate(struct inode *inode, loff_t new_size)

 	if (ei->type != TYPE_FILE && ei->type != TYPE_DIR)

 		return -EPERM;

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi);

 	num_clusters_phys =

@@ -220,7 +220,7 @@ int __exfat_truncate(struct inode *inode, loff_t new_size)

 	if (exfat_free_cluster(inode, &clu))

 		return -EIO;

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 	return 0;

 }

diff --git a/src/inode.c b/src/inode.c

index f0160a7892a815cf22a0e495db104a9ebea35615..7f90204adef53027dd1eb4348141394af5548b1b 100644

--- a/src/inode.c

+++ b/src/inode.c

@@ -39,7 +39,7 @@ static int __exfat_write_inode(struct inode *inode, int sync)

 	if (is_dir && ei->dir.dir == sbi->root_dir && ei->entry == -1)

 		return 0;

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	/* get the directory entry of given file or directory */

 	es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES);

@@ -167,7 +167,7 @@ static int exfat_map_cluster(struct inode *inode, unsigned int clu_offset,

 	}

 	if (*clu == EXFAT_EOF_CLUSTER) {

-		exfat_set_vol_flags(sb, VOL_DIRTY);

+		exfat_set_volume_dirty(sb);

 		new_clu.dir = (last_clu == EXFAT_EOF_CLUSTER) ?

 				EXFAT_EOF_CLUSTER : last_clu + 1;

diff --git a/src/namei.c b/src/namei.c

index 126ed3ba8f4791859a11bdfac05a1b71847b2e22..e73f20f66cb2e1c1c3c20b4a62bad8210fda6e8b 100644

--- a/src/namei.c

+++ b/src/namei.c

@@ -562,10 +562,10 @@ static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,

 	int err;

 	mutex_lock(&EXFAT_SB(sb)->s_lock);

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,

 		&info;;

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 	if (err)

 		goto unlock;

@@ -834,7 +834,7 @@ static int exfat_unlink(struct inode *dir, struct dentry *dentry)

 	num_entries++;

 	brelse(bh);

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	/* update the directory entry */

 	if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {

 		err = -EIO;

@@ -843,7 +843,7 @@ static int exfat_unlink(struct inode *dir, struct dentry *dentry)

 	/* This doesn't modify ei */

 	ei->dir.dir = DIR_DELETED;

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 	inode_inc_iversion(dir);

 	dir->i_mtime = dir->i_atime = current_time(dir);

@@ -873,10 +873,10 @@ static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)

 	int err;

 	mutex_lock(&EXFAT_SB(sb)->s_lock);

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,

 		&info;;

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 	if (err)

 		goto unlock;

@@ -1001,14 +1001,14 @@ static int exfat_rmdir(struct inode *dir, struct dentry *dentry)

 	num_entries++;

 	brelse(bh);

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);

 	if (err) {

 		exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err);

 		goto unlock;

 	}

 	ei->dir.dir = DIR_DELETED;

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 	inode_inc_iversion(dir);

 	dir->i_mtime = dir->i_atime = current_time(dir);

@@ -1300,7 +1300,7 @@ static int __exfat_rename(struct inode *old_parent_inode,

 	if (ret)

 		goto out;

-	exfat_set_vol_flags(sb, VOL_DIRTY);

+	exfat_set_volume_dirty(sb);

 	if (olddir.dir == newdir.dir)

 		ret = exfat_rename_file(new_parent_inode, &olddir, dentry,

@@ -1355,7 +1355,7 @@ static int __exfat_rename(struct inode *old_parent_inode,

 		 */

 		new_ei->dir.dir = DIR_DELETED;

 	}

-	exfat_set_vol_flags(sb, VOL_CLEAN);

+	exfat_clear_volume_dirty(sb);

 out:

 	return ret;

 }

diff --git a/src/super.c b/src/super.c

index b5bf6dedbe1159fb4aa0b501ab7e5b8f2051a063..3b6a1659892ffd6ee3a94f6aa0f8bfca65fba9ae 100644

--- a/src/super.c

+++ b/src/super.c

@@ -63,7 +63,7 @@ static int exfat_sync_fs(struct super_block *sb, int wait)

 	/* If there are some dirty buffers in the bdev inode */

 	mutex_lock(&sbi->s_lock);

 	sync_blockdev(sb->s_bdev);

-	if (exfat_set_vol_flags(sb, VOL_CLEAN))

+	if (exfat_clear_volume_dirty(sb))

 		err = -EIO;

 	mutex_unlock(&sbi->s_lock);

 	return err;

@@ -96,17 +96,20 @@ static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf)

 	return 0;

 }

-int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag)

+static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags)

 {

 	struct exfat_sb_info *sbi = EXFAT_SB(sb);

 	struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data;

 	bool sync;

+	/* retain persistent-flags */

+	new_flags |= sbi->vol_flags_persistent;

+

 	/* flags are not changed */

-	if (sbi->vol_flag == new_flag)

+	if (sbi->vol_flags == new_flags)

 		return 0;

-	sbi->vol_flag = new_flag;

+	sbi->vol_flags = new_flags;

 	/* skip updating volume dirty flag,

 	 * if this volume has been mounted with read-only

@@ -114,9 +117,9 @@ int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag)

 	if (sb_rdonly(sb))

 		return 0;

-	p_boot->vol_flags = cpu_to_le16(new_flag);

+	p_boot->vol_flags = cpu_to_le16(new_flags);

-	if (new_flag == VOL_DIRTY && !buffer_dirty(sbi->boot_bh))

+	if ((new_flags & VOLUME_DIRTY) && !buffer_dirty(sbi->boot_bh))

 		sync = true;

 	else

 		sync = false;

@@ -129,6 +132,20 @@ int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flag)

 	return 0;

 }

+int exfat_set_volume_dirty(struct super_block *sb)

+{

+	struct exfat_sb_info *sbi = EXFAT_SB(sb);

+

+	return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY);

+}

+

+int exfat_clear_volume_dirty(struct super_block *sb)

+{

+	struct exfat_sb_info *sbi = EXFAT_SB(sb);

+

+	return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY);

+}

+

 static int exfat_show_options(struct seq_file *m, struct dentry *root)

 {

 	struct super_block *sb = root->d_sb;

@@ -457,7 +474,8 @@ static int exfat_read_boot_sector(struct super_block *sb)

 	sbi->dentries_per_clu = 1 <<

 		(sbi->cluster_size_bits - DENTRY_SIZE_BITS);

-	sbi->vol_flag = le16_to_cpu(p_boot->vol_flags);

+	sbi->vol_flags = le16_to_cpu(p_boot->vol_flags);

+	sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE);

 	sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER;

 	sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED;

@@ -472,9 +490,9 @@ static int exfat_read_boot_sector(struct super_block *sb)

 		exfat_err(sb, "bogus data start sector");

 		return -EINVAL;

 	}

-	if (sbi->vol_flag & VOL_DIRTY)

+	if (sbi->vol_flags & VOLUME_DIRTY)

 		exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck.");

-	if (sbi->vol_flag & ERR_MEDIUM)

+	if (sbi->vol_flags & MEDIA_FAILURE)

 		exfat_warn(sb, "Medium has reported failures. Some data may be lost.");

 	/* exFAT file size is limited by a disk volume size */

-- 

2.31.1