ext4: Move orphan inode handling into a separate file

Move functions for handling orphan inodes into a new file
fs/ext4/orphan.c to have them in one place and somewhat reduce size of
other files. No code changes.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-2-jack@suse.czSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/Makefile

@@ -10,7 +10,7 @@ ext4-y	:= balloc.o bitmap.o block_validity.o dir.o ext4_jbd2.o extents.o \
 		indirect.o inline.o inode.o ioctl.o mballoc.o migrate.o \
 		mmp.o move_extent.o namei.o page-io.o readpage.o resize.o \
 		super.o symlink.o sysfs.o xattr.o xattr_hurd.o xattr_trusted.o \
-		xattr_user.o fast_commit.o
+		xattr_user.o fast_commit.o orphan.o
 
 ext4-$(CONFIG_EXT4_FS_POSIX_ACL)	+= acl.o
 ext4-$(CONFIG_EXT4_FS_SECURITY)		+= xattr_security.o

fs/ext4/ext4.h

@@ -2171,6 +2171,8 @@ static inline bool ext4_has_incompat_features(struct super_block *sb)
 	return (EXT4_SB(sb)->s_es->s_feature_incompat != 0);
 }
 
+extern int ext4_feature_set_ok(struct super_block *sb, int readonly);
+
 /*
  * Superblock flags
  */
@@ -3031,8 +3033,6 @@ extern int ext4_init_new_dir(handle_t *handle, struct inode *dir,
 			     struct inode *inode);
 extern int ext4_dirblock_csum_verify(struct inode *inode,
 				     struct buffer_head *bh);
-extern int ext4_orphan_add(handle_t *, struct inode *);
-extern int ext4_orphan_del(handle_t *, struct inode *);
 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 				__u32 start_minor_hash, __u32 *next_hash);
 extern int ext4_search_dir(struct buffer_head *bh,
@@ -3501,6 +3501,7 @@ static inline bool ext4_is_quota_journalled(struct super_block *sb)
 	return (ext4_has_feature_quota(sb) ||
 		sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]);
 }
+int ext4_enable_quotas(struct super_block *sb);
 #endif
 
 /*
@@ -3762,6 +3763,12 @@ extern void ext4_stop_mmpd(struct ext4_sb_info *sbi);
 /* verity.c */
 extern const struct fsverity_operations ext4_verityops;
 
+/* orphan.c */
+extern int ext4_orphan_add(handle_t *, struct inode *);
+extern int ext4_orphan_del(handle_t *, struct inode *);
+extern void ext4_orphan_cleanup(struct super_block *sb,
+				struct ext4_super_block *es);
+
 /*
  * Add new method to test whether block and inode bitmaps are properly
  * initialized. With uninit_bg reading the block from disk is not enough

fs/ext4/namei.c

@@ -3054,188 +3054,6 @@ bool ext4_empty_dir(struct inode *inode)
 	return true;
 }
 
-/*
- * ext4_orphan_add() links an unlinked or truncated inode into a list of
- * such inodes, starting at the superblock, in case we crash before the
- * file is closed/deleted, or in case the inode truncate spans multiple
- * transactions and the last transaction is not recovered after a crash.
- *
- * At filesystem recovery time, we walk this list deleting unlinked
- * inodes and truncating linked inodes in ext4_orphan_cleanup().
- *
- * Orphan list manipulation functions must be called under i_mutex unless
- * we are just creating the inode or deleting it.
- */
-int ext4_orphan_add(handle_t *handle, struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	struct ext4_iloc iloc;
-	int err = 0, rc;
-	bool dirty = false;
-
-	if (!sbi->s_journal || is_bad_inode(inode))
-		return 0;
-
-	WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
-		     !inode_is_locked(inode));
-	/*
-	 * Exit early if inode already is on orphan list. This is a big speedup
-	 * since we don't have to contend on the global s_orphan_lock.
-	 */
-	if (!list_empty(&EXT4_I(inode)->i_orphan))
-		return 0;
-
-	/*
-	 * Orphan handling is only valid for files with data blocks
-	 * being truncated, or files being unlinked. Note that we either
-	 * hold i_mutex, or the inode can not be referenced from outside,
-	 * so i_nlink should not be bumped due to race
-	 */
-	ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-		  S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);
-
-	BUFFER_TRACE(sbi->s_sbh, "get_write_access");
-	err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh,
-					    EXT4_JTR_NONE);
-	if (err)
-		goto out;
-
-	err = ext4_reserve_inode_write(handle, inode, &iloc);
-	if (err)
-		goto out;
-
-	mutex_lock(&sbi->s_orphan_lock);
-	/*
-	 * Due to previous errors inode may be already a part of on-disk
-	 * orphan list. If so skip on-disk list modification.
-	 */
-	if (!NEXT_ORPHAN(inode) || NEXT_ORPHAN(inode) >
-	    (le32_to_cpu(sbi->s_es->s_inodes_count))) {
-		/* Insert this inode at the head of the on-disk orphan list */
-		NEXT_ORPHAN(inode) = le32_to_cpu(sbi->s_es->s_last_orphan);
-		lock_buffer(sbi->s_sbh);
-		sbi->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
-		ext4_superblock_csum_set(sb);
-		unlock_buffer(sbi->s_sbh);
-		dirty = true;
-	}
-	list_add(&EXT4_I(inode)->i_orphan, &sbi->s_orphan);
-	mutex_unlock(&sbi->s_orphan_lock);
-
-	if (dirty) {
-		err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
-		rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
-		if (!err)
-			err = rc;
-		if (err) {
-			/*
-			 * We have to remove inode from in-memory list if
-			 * addition to on disk orphan list failed. Stray orphan
-			 * list entries can cause panics at unmount time.
-			 */
-			mutex_lock(&sbi->s_orphan_lock);
-			list_del_init(&EXT4_I(inode)->i_orphan);
-			mutex_unlock(&sbi->s_orphan_lock);
-		}
-	} else
-		brelse(iloc.bh);
-
-	jbd_debug(4, "superblock will point to %lu\n", inode->i_ino);
-	jbd_debug(4, "orphan inode %lu will point to %d\n",
-			inode->i_ino, NEXT_ORPHAN(inode));
-out:
-	ext4_std_error(sb, err);
-	return err;
-}
-
-/*
- * ext4_orphan_del() removes an unlinked or truncated inode from the list
- * of such inodes stored on disk, because it is finally being cleaned up.
- */
-int ext4_orphan_del(handle_t *handle, struct inode *inode)
-{
-	struct list_head *prev;
-	struct ext4_inode_info *ei = EXT4_I(inode);
-	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
-	__u32 ino_next;
-	struct ext4_iloc iloc;
-	int err = 0;
-
-	if (!sbi->s_journal && !(sbi->s_mount_state & EXT4_ORPHAN_FS))
-		return 0;
-
-	WARN_ON_ONCE(!(inode->i_state & (I_NEW | I_FREEING)) &&
-		     !inode_is_locked(inode));
-	/* Do this quick check before taking global s_orphan_lock. */
-	if (list_empty(&ei->i_orphan))
-		return 0;
-
-	if (handle) {
-		/* Grab inode buffer early before taking global s_orphan_lock */
-		err = ext4_reserve_inode_write(handle, inode, &iloc);
-	}
-
-	mutex_lock(&sbi->s_orphan_lock);
-	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);
-
-	prev = ei->i_orphan.prev;
-	list_del_init(&ei->i_orphan);
-
-	/* If we're on an error path, we may not have a valid
-	 * transaction handle with which to update the orphan list on
-	 * disk, but we still need to remove the inode from the linked
-	 * list in memory. */
-	if (!handle || err) {
-		mutex_unlock(&sbi->s_orphan_lock);
-		goto out_err;
-	}
-
-	ino_next = NEXT_ORPHAN(inode);
-	if (prev == &sbi->s_orphan) {
-		jbd_debug(4, "superblock will point to %u\n", ino_next);
-		BUFFER_TRACE(sbi->s_sbh, "get_write_access");
-		err = ext4_journal_get_write_access(handle, inode->i_sb,
-						    sbi->s_sbh, EXT4_JTR_NONE);
-		if (err) {
-			mutex_unlock(&sbi->s_orphan_lock);
-			goto out_brelse;
-		}
-		lock_buffer(sbi->s_sbh);
-		sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
-		ext4_superblock_csum_set(inode->i_sb);
-		unlock_buffer(sbi->s_sbh);
-		mutex_unlock(&sbi->s_orphan_lock);
-		err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh);
-	} else {
-		struct ext4_iloc iloc2;
-		struct inode *i_prev =
-			&list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode;
-
-		jbd_debug(4, "orphan inode %lu will point to %u\n",
-			  i_prev->i_ino, ino_next);
-		err = ext4_reserve_inode_write(handle, i_prev, &iloc2);
-		if (err) {
-			mutex_unlock(&sbi->s_orphan_lock);
-			goto out_brelse;
-		}
-		NEXT_ORPHAN(i_prev) = ino_next;
-		err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2);
-		mutex_unlock(&sbi->s_orphan_lock);
-	}
-	if (err)
-		goto out_brelse;
-	NEXT_ORPHAN(inode) = 0;
-	err = ext4_mark_iloc_dirty(handle, inode, &iloc);
-out_err:
-	ext4_std_error(inode->i_sb, err);
-	return err;
-
-out_brelse:
-	brelse(iloc.bh);
-	goto out_err;
-}
-
 static int ext4_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	int retval;

fs/ext4/super.c

@@ -80,7 +80,6 @@ static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
 		       const char *dev_name, void *data);
 static inline int ext2_feature_set_ok(struct super_block *sb);
 static inline int ext3_feature_set_ok(struct super_block *sb);
-static int ext4_feature_set_ok(struct super_block *sb, int readonly);
 static void ext4_destroy_lazyinit_thread(void);
 static void ext4_unregister_li_request(struct super_block *sb);
 static void ext4_clear_request_list(void);
@@ -1585,14 +1584,12 @@ static int ext4_mark_dquot_dirty(struct dquot *dquot);
 static int ext4_write_info(struct super_block *sb, int type);
 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
 			 const struct path *path);
-static int ext4_quota_on_mount(struct super_block *sb, int type);
 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
 			       size_t len, loff_t off);
 static ssize_t ext4_quota_write(struct super_block *sb, int type,
 				const char *data, size_t len, loff_t off);
 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
 			     unsigned int flags);
-static int ext4_enable_quotas(struct super_block *sb);
 
 static struct dquot **ext4_get_dquots(struct inode *inode)
 {
@@ -2970,169 +2967,6 @@ static int ext4_check_descriptors(struct super_block *sb,
 	return 1;
 }
 
-/* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
- * the superblock) which were deleted from all directories, but held open by
- * a process at the time of a crash.  We walk the list and try to delete these
- * inodes at recovery time (only with a read-write filesystem).
- *
- * In order to keep the orphan inode chain consistent during traversal (in
- * case of crash during recovery), we link each inode into the superblock
- * orphan list_head and handle it the same way as an inode deletion during
- * normal operation (which journals the operations for us).
- *
- * We only do an iget() and an iput() on each inode, which is very safe if we
- * accidentally point at an in-use or already deleted inode.  The worst that
- * can happen in this case is that we get a "bit already cleared" message from
- * ext4_free_inode().  The only reason we would point at a wrong inode is if
- * e2fsck was run on this filesystem, and it must have already done the orphan
- * inode cleanup for us, so we can safely abort without any further action.
- */
-static void ext4_orphan_cleanup(struct super_block *sb,
-				struct ext4_super_block *es)
-{
-	unsigned int s_flags = sb->s_flags;
-	int ret, nr_orphans = 0, nr_truncates = 0;
-#ifdef CONFIG_QUOTA
-	int quota_update = 0;
-	int i;
-#endif
-	if (!es->s_last_orphan) {
-		jbd_debug(4, "no orphan inodes to clean up\n");
-		return;
-	}
-
-	if (bdev_read_only(sb->s_bdev)) {
-		ext4_msg(sb, KERN_ERR, "write access "
-			"unavailable, skipping orphan cleanup");
-		return;
-	}
-
-	/* Check if feature set would not allow a r/w mount */
-	if (!ext4_feature_set_ok(sb, 0)) {
-		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
-			 "unknown ROCOMPAT features");
-		return;
-	}
-
-	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
-		/* don't clear list on RO mount w/ errors */
-		if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
-			ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
-				  "clearing orphan list.\n");
-			es->s_last_orphan = 0;
-		}
-		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
-		return;
-	}
-
-	if (s_flags & SB_RDONLY) {
-		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
-		sb->s_flags &= ~SB_RDONLY;
-	}
-#ifdef CONFIG_QUOTA
-	/*
-	 * Turn on quotas which were not enabled for read-only mounts if
-	 * filesystem has quota feature, so that they are updated correctly.
-	 */
-	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
-		int ret = ext4_enable_quotas(sb);
-
-		if (!ret)
-			quota_update = 1;
-		else
-			ext4_msg(sb, KERN_ERR,
-				"Cannot turn on quotas: error %d", ret);
-	}
-
-	/* Turn on journaled quotas used for old sytle */
-	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
-		if (EXT4_SB(sb)->s_qf_names[i]) {
-			int ret = ext4_quota_on_mount(sb, i);
-
-			if (!ret)
-				quota_update = 1;
-			else
-				ext4_msg(sb, KERN_ERR,
-					"Cannot turn on journaled "
-					"quota: type %d: error %d", i, ret);
-		}
-	}
-#endif
-
-	while (es->s_last_orphan) {
-		struct inode *inode;
-
-		/*
-		 * We may have encountered an error during cleanup; if
-		 * so, skip the rest.
-		 */
-		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
-			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
-			es->s_last_orphan = 0;
-			break;
-		}
-
-		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
-		if (IS_ERR(inode)) {
-			es->s_last_orphan = 0;
-			break;
-		}
-
-		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
-		dquot_initialize(inode);
-		if (inode->i_nlink) {
-			if (test_opt(sb, DEBUG))
-				ext4_msg(sb, KERN_DEBUG,
-					"%s: truncating inode %lu to %lld bytes",
-					__func__, inode->i_ino, inode->i_size);
-			jbd_debug(2, "truncating inode %lu to %lld bytes\n",
-				  inode->i_ino, inode->i_size);
-			inode_lock(inode);
-			truncate_inode_pages(inode->i_mapping, inode->i_size);
-			ret = ext4_truncate(inode);
-			if (ret) {
-				/*
-				 * We need to clean up the in-core orphan list
-				 * manually if ext4_truncate() failed to get a
-				 * transaction handle.
-				 */
-				ext4_orphan_del(NULL, inode);
-				ext4_std_error(inode->i_sb, ret);
-			}
-			inode_unlock(inode);
-			nr_truncates++;
-		} else {
-			if (test_opt(sb, DEBUG))
-				ext4_msg(sb, KERN_DEBUG,
-					"%s: deleting unreferenced inode %lu",
-					__func__, inode->i_ino);
-			jbd_debug(2, "deleting unreferenced inode %lu\n",
-				  inode->i_ino);
-			nr_orphans++;
-		}
-		iput(inode);  /* The delete magic happens here! */
-	}
-
-#define PLURAL(x) (x), ((x) == 1) ? "" : "s"
-
-	if (nr_orphans)
-		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
-		       PLURAL(nr_orphans));
-	if (nr_truncates)
-		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
-		       PLURAL(nr_truncates));
-#ifdef CONFIG_QUOTA
-	/* Turn off quotas if they were enabled for orphan cleanup */
-	if (quota_update) {
-		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
-			if (sb_dqopt(sb)->files[i])
-				dquot_quota_off(sb, i);
-		}
-	}
-#endif
-	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
-}
-
 /*
  * Maximal extent format file size.
  * Resulting logical blkno at s_maxbytes must fit in our on-disk
@@ -3312,7 +3146,7 @@ static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
  * Returns 1 if this filesystem can be mounted as requested,
  * 0 if it cannot be.
  */
-static int ext4_feature_set_ok(struct super_block *sb, int readonly)
+int ext4_feature_set_ok(struct super_block *sb, int readonly)
 {
 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
 		ext4_msg(sb, KERN_ERR,
@@ -6334,16 +6168,6 @@ static int ext4_write_info(struct super_block *sb, int type)
 	return ret;
 }
 
-/*
- * Turn on quotas during mount time - we need to find
- * the quota file and such...
- */
-static int ext4_quota_on_mount(struct super_block *sb, int type)
-{
-	return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
-					EXT4_SB(sb)->s_jquota_fmt, type);
-}
-
 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
 {
 	struct ext4_inode_info *ei = EXT4_I(inode);
@@ -6473,7 +6297,7 @@ static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
 }
 
 /* Enable usage tracking for all quota types. */
-static int ext4_enable_quotas(struct super_block *sb)
+int ext4_enable_quotas(struct super_block *sb)
 {
 	int type, err = 0;
 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {