bcachefs: Casefold is now a regular opts.h option

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Author: Kent Overstreet

fs/bcachefs/bcachefs_format.h

@@ -867,6 +867,7 @@ LE64_BITMASK(BCH_SB_VERSION_INCOMPAT_ALLOWED,
 LE64_BITMASK(BCH_SB_SHARD_INUMS_NBITS,	struct bch_sb, flags[6],  0,  4);
 LE64_BITMASK(BCH_SB_WRITE_ERROR_TIMEOUT,struct bch_sb, flags[6],  4, 14);
 LE64_BITMASK(BCH_SB_CSUM_ERR_RETRY_NR,	struct bch_sb, flags[6], 14, 20);
+LE64_BITMASK(BCH_SB_CASEFOLD,		struct bch_sb, flags[6], 22, 23);
 
 static inline __u64 BCH_SB_COMPRESSION_TYPE(const struct bch_sb *sb)
 {

fs/bcachefs/fs.c

@@ -53,16 +53,19 @@ static void bch2_vfs_inode_init(struct btree_trans *, subvol_inum,
 				struct bch_subvolume *);
 
 /* Set VFS inode flags from bcachefs inode: */
-static inline void bch2_inode_flags_to_vfs(struct bch_inode_info *inode)
+static inline void bch2_inode_flags_to_vfs(struct bch_fs *c, struct bch_inode_info *inode)
 {
 	static const __maybe_unused unsigned bch_flags_to_vfs[] = {
 		[__BCH_INODE_sync]		= S_SYNC,
 		[__BCH_INODE_immutable]		= S_IMMUTABLE,
 		[__BCH_INODE_append]		= S_APPEND,
 		[__BCH_INODE_noatime]		= S_NOATIME,
-		[__BCH_INODE_casefolded]	= S_CASEFOLD,
 	};
+
 	set_flags(bch_flags_to_vfs, inode->ei_inode.bi_flags, inode->v.i_flags);
+
+	if (bch2_inode_casefold(c, &inode->ei_inode))
+		inode->v.i_flags |= S_CASEFOLD;
 }
 
 void bch2_inode_update_after_write(struct btree_trans *trans,
@@ -93,7 +96,7 @@ void bch2_inode_update_after_write(struct btree_trans *trans,
 
 	inode->ei_inode		= *bi;
 
-	bch2_inode_flags_to_vfs(inode);
+	bch2_inode_flags_to_vfs(c, inode);
 }
 
 int __must_check bch2_write_inode(struct bch_fs *c,
@@ -1470,7 +1473,6 @@ static const __maybe_unused unsigned bch_flags_to_uflags[] = {
 	[__BCH_INODE_append]		= FS_APPEND_FL,
 	[__BCH_INODE_nodump]		= FS_NODUMP_FL,
 	[__BCH_INODE_noatime]		= FS_NOATIME_FL,
-	[__BCH_INODE_casefolded]	= FS_CASEFOLD_FL,
 };
 
 /* bcachefs inode flags -> FS_IOC_FSGETXATTR: */
@@ -1486,13 +1488,14 @@ static int bch2_fileattr_get(struct dentry *dentry,
 			     struct fileattr *fa)
 {
 	struct bch_inode_info *inode = to_bch_ei(d_inode(dentry));
+	struct bch_fs *c = inode->v.i_sb->s_fs_info;
 
 	fileattr_fill_xflags(fa, map_flags(bch_flags_to_xflags, inode->ei_inode.bi_flags));
 
 	if (inode->ei_inode.bi_fields_set & (1 << Inode_opt_project))
 		fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
 
-	if (inode->ei_inode.bi_flags & BCH_INODE_casefolded)
+	if (bch2_inode_casefold(c, &inode->ei_inode))
 		fa->flags |= FS_CASEFOLD_FL;
 
 	fa->fsx_projid = inode->ei_qid.q[QTYP_PRJ];
@@ -1504,6 +1507,8 @@ struct flags_set {
 	unsigned		flags;
 	unsigned		projid;
 	bool			set_project;
+	bool			set_casefold;
+	bool			casefold;
 };
 
 static int fssetxattr_inode_update_fn(struct btree_trans *trans,
@@ -1518,15 +1523,12 @@ static int fssetxattr_inode_update_fn(struct btree_trans *trans,
 	 * We're relying on btree locking here for exclusion with other ioctl
 	 * calls - use the flags in the btree (@bi), not inode->i_flags:
 	 */
-	unsigned newflags = s->flags;
-	unsigned oldflags = bi->bi_flags & s->mask;
-
 	if (!S_ISREG(bi->bi_mode) &&
 	    !S_ISDIR(bi->bi_mode) &&
-	    (newflags & (BCH_INODE_nodump|BCH_INODE_noatime)) != newflags)
+	    (s->flags & (BCH_INODE_nodump|BCH_INODE_noatime)) != s->flags)
 		return -EINVAL;
 
-	if ((newflags ^ oldflags) & BCH_INODE_casefolded) {
+	if (s->casefold != bch2_inode_casefold(c, bi)) {
 #ifdef CONFIG_UNICODE
 		int ret = 0;
 		/* Not supported on individual files. */
@@ -1546,6 +1548,10 @@ static int fssetxattr_inode_update_fn(struct btree_trans *trans,
 			return ret;
 
 		bch2_check_set_feature(c, BCH_FEATURE_casefolding);
+
+		bi->bi_casefold = s->casefold + 1;
+		bi->bi_fields_set |= BIT(Inode_opt_casefold);
+
 #else
 		printk(KERN_ERR "Cannot use casefolding on a kernel without CONFIG_UNICODE\n");
 		return -EOPNOTSUPP;
@@ -1558,7 +1564,7 @@ static int fssetxattr_inode_update_fn(struct btree_trans *trans,
 	}
 
 	bi->bi_flags &= ~s->mask;
-	bi->bi_flags |= newflags;
+	bi->bi_flags |= s->flags;
 
 	bi->bi_ctime = timespec_to_bch2_time(c, current_time(&inode->v));
 	return 0;
@@ -1598,6 +1604,11 @@ static int bch2_fileattr_set(struct mnt_idmap *idmap,
 
 	if (fa->flags_valid) {
 		s.mask = map_defined(bch_flags_to_uflags);
+
+		s.set_casefold = true;
+		s.casefold = (fa->flags & FS_CASEFOLD_FL) != 0;
+		fa->flags &= ~FS_CASEFOLD_FL;
+
 		s.flags |= map_flags_rev(bch_flags_to_uflags, fa->flags);
 		if (fa->flags)
 			return -EOPNOTSUPP;

fs/bcachefs/inode.h

@@ -243,6 +243,14 @@ static inline unsigned bkey_inode_mode(struct bkey_s_c k)
 	}
 }
 
+static inline bool bch2_inode_casefold(struct bch_fs *c, const struct bch_inode_unpacked *bi)
+{
+	/* inode apts are stored with a +1 bias: 0 means "unset, use fs opt" */
+	return bi->bi_casefold
+		? bi->bi_casefold - 1
+		: c->opts.casefold;
+}
+
 /* i_nlink: */
 
 static inline unsigned nlink_bias(umode_t mode)

fs/bcachefs/inode_format.h

@@ -103,7 +103,8 @@ struct bch_inode_generation {
 	x(bi_parent_subvol,		32)	\
 	x(bi_nocow,			8)	\
 	x(bi_depth,			32)	\
-	x(bi_inodes_32bit,		8)
+	x(bi_inodes_32bit,		8)	\
+	x(bi_casefold,			8)
 
 /* subset of BCH_INODE_FIELDS */
 #define BCH_INODE_OPTS()			\
@@ -117,7 +118,8 @@ struct bch_inode_generation {
 	x(background_target,		16)	\
 	x(erasure_code,			16)	\
 	x(nocow,			8)	\
-	x(inodes_32bit,			8)
+	x(inodes_32bit,			8)	\
+	x(casefold,			8)
 
 enum inode_opt_id {
 #define x(name, ...)				\
@@ -137,8 +139,7 @@ enum inode_opt_id {
 	x(i_sectors_dirty,		6)	\
 	x(unlinked,			7)	\
 	x(backptr_untrusted,		8)	\
-	x(has_child_snapshot,		9)	\
-	x(casefolded,			10)
+	x(has_child_snapshot,		9)
 
 /* bits 20+ reserved for packed fields below: */
 

fs/bcachefs/namei.c

@@ -47,10 +47,6 @@ int bch2_create_trans(struct btree_trans *trans,
 	if (ret)
 		goto err;
 
-	/* Inherit casefold state from parent. */
-	if (S_ISDIR(mode))
-		new_inode->bi_flags |= dir_u->bi_flags & BCH_INODE_casefolded;
-
 	if (!(flags & BCH_CREATE_SNAPSHOT)) {
 		/* Normal create path - allocate a new inode: */
 		bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);

fs/bcachefs/opts.h

@@ -228,6 +228,11 @@ enum fsck_err_opts {
 	  OPT_BOOL(),							\
 	  BCH_SB_ERASURE_CODE,		false,				\
 	  NULL,		"Enable erasure coding (DO NOT USE YET)")	\
+	x(casefold,			u8,				\
+	  OPT_FS|OPT_INODE|OPT_FORMAT,					\
+	  OPT_BOOL(),							\
+	  BCH_SB_CASEFOLD,		false,				\
+	  NULL,		"Dirent lookups are casefolded")		\
 	x(inodes_32bit,			u8,				\
 	  OPT_FS|OPT_INODE|OPT_FORMAT|OPT_MOUNT|OPT_RUNTIME,		\
 	  OPT_BOOL(),							\

fs/bcachefs/str_hash.h

@@ -33,7 +33,7 @@ bch2_str_hash_opt_to_type(struct bch_fs *c, enum bch_str_hash_opts opt)
 
 struct bch_hash_info {
 	u8			type;
-	struct unicode_map 	*cf_encoding;
+	struct unicode_map	*cf_encoding;
 	/*
 	 * For crc32 or crc64 string hashes the first key value of
 	 * the siphash_key (k0) is used as the key.
@@ -44,11 +44,10 @@ struct bch_hash_info {
 static inline struct bch_hash_info
 bch2_hash_info_init(struct bch_fs *c, const struct bch_inode_unpacked *bi)
 {
-	/* XXX ick */
 	struct bch_hash_info info = {
 		.type = INODE_STR_HASH(bi),
 #ifdef CONFIG_UNICODE
-		.cf_encoding = !!(bi->bi_flags & BCH_INODE_casefolded) ? c->cf_encoding : NULL,
+		.cf_encoding = bch2_inode_casefold(c, bi) ? c->cf_encoding : NULL,
 #endif
 		.siphash_key = { .k0 = bi->bi_hash_seed }
 	};