bcachefs: Implement fileattr_(get|set)

inode_operations.fileattr_(get|set) didn't exist when the various flag
ioctls where implemented - but they do now, which means we can delete a
bunch of ioctl code in favor of standard VFS level wrappers.

Closes: https://lore.kernel.org/linux-bcachefs/7ltgrgqgfummyrlvw7hnfhnu42rfiamoq3lpcvrjnlyytldmzp@yazbhusnztqn/
Cc: Petr Vorel <pvorel@suse.cz>
Cc: Andrea Cervesato <andrea.cervesato@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Author: Kent Overstreet

fs/bcachefs/fs-ioctl.c

@@ -21,206 +21,6 @@
 #define FSOP_GOING_FLAGS_LOGFLUSH	0x1	/* flush log but not data */
 #define FSOP_GOING_FLAGS_NOLOGFLUSH	0x2	/* don't flush log nor data */
 
-struct flags_set {
-	unsigned		mask;
-	unsigned		flags;
-
-	unsigned		projid;
-
-	bool			set_projinherit;
-	bool			projinherit;
-};
-
-static int bch2_inode_flags_set(struct btree_trans *trans,
-				struct bch_inode_info *inode,
-				struct bch_inode_unpacked *bi,
-				void *p)
-{
-	struct bch_fs *c = inode->v.i_sb->s_fs_info;
-	/*
-	 * We're relying on btree locking here for exclusion with other ioctl
-	 * calls - use the flags in the btree (@bi), not inode->i_flags:
-	 */
-	struct flags_set *s = p;
-	unsigned newflags = s->flags;
-	unsigned oldflags = bi->bi_flags & s->mask;
-
-	if (((newflags ^ oldflags) & (BCH_INODE_append|BCH_INODE_immutable)) &&
-	    !capable(CAP_LINUX_IMMUTABLE))
-		return -EPERM;
-
-	if (!S_ISREG(bi->bi_mode) &&
-	    !S_ISDIR(bi->bi_mode) &&
-	    (newflags & (BCH_INODE_nodump|BCH_INODE_noatime)) != newflags)
-		return -EINVAL;
-
-	if ((newflags ^ oldflags) & BCH_INODE_casefolded) {
-#ifdef CONFIG_UNICODE
-		int ret = 0;
-		/* Not supported on individual files. */
-		if (!S_ISDIR(bi->bi_mode))
-			return -EOPNOTSUPP;
-
-		/*
-		 * Make sure the dir is empty, as otherwise we'd need to
-		 * rehash everything and update the dirent keys.
-		 */
-		ret = bch2_empty_dir_trans(trans, inode_inum(inode));
-		if (ret < 0)
-			return ret;
-
-		ret = bch2_request_incompat_feature(c, bcachefs_metadata_version_casefolding);
-		if (ret)
-			return ret;
-
-		bch2_check_set_feature(c, BCH_FEATURE_casefolding);
-#else
-		printk(KERN_ERR "Cannot use casefolding on a kernel without CONFIG_UNICODE\n");
-		return -EOPNOTSUPP;
-#endif
-	}
-
-	if (s->set_projinherit) {
-		bi->bi_fields_set &= ~(1 << Inode_opt_project);
-		bi->bi_fields_set |= ((int) s->projinherit << Inode_opt_project);
-	}
-
-	bi->bi_flags &= ~s->mask;
-	bi->bi_flags |= newflags;
-
-	bi->bi_ctime = timespec_to_bch2_time(c, current_time(&inode->v));
-	return 0;
-}
-
-static int bch2_ioc_getflags(struct bch_inode_info *inode, int __user *arg)
-{
-	unsigned flags = map_flags(bch_flags_to_uflags, inode->ei_inode.bi_flags);
-
-	return put_user(flags, arg);
-}
-
-static int bch2_ioc_setflags(struct bch_fs *c,
-			     struct file *file,
-			     struct bch_inode_info *inode,
-			     void __user *arg)
-{
-	struct flags_set s = { .mask = map_defined(bch_flags_to_uflags) };
-	unsigned uflags;
-	int ret;
-
-	if (get_user(uflags, (int __user *) arg))
-		return -EFAULT;
-
-	s.flags = map_flags_rev(bch_flags_to_uflags, uflags);
-	if (uflags)
-		return -EOPNOTSUPP;
-
-	ret = mnt_want_write_file(file);
-	if (ret)
-		return ret;
-
-	inode_lock(&inode->v);
-	if (!inode_owner_or_capable(file_mnt_idmap(file), &inode->v)) {
-		ret = -EACCES;
-		goto setflags_out;
-	}
-
-	mutex_lock(&inode->ei_update_lock);
-	ret   = bch2_subvol_is_ro(c, inode->ei_inum.subvol) ?:
-		bch2_write_inode(c, inode, bch2_inode_flags_set, &s,
-			       ATTR_CTIME);
-	mutex_unlock(&inode->ei_update_lock);
-
-setflags_out:
-	inode_unlock(&inode->v);
-	mnt_drop_write_file(file);
-	return ret;
-}
-
-static int bch2_ioc_fsgetxattr(struct bch_inode_info *inode,
-			       struct fsxattr __user *arg)
-{
-	struct fsxattr fa = { 0 };
-
-	fa.fsx_xflags = 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;
-
-	fa.fsx_projid = inode->ei_qid.q[QTYP_PRJ];
-
-	if (copy_to_user(arg, &fa, sizeof(fa)))
-		return -EFAULT;
-
-	return 0;
-}
-
-static int fssetxattr_inode_update_fn(struct btree_trans *trans,
-				      struct bch_inode_info *inode,
-				      struct bch_inode_unpacked *bi,
-				      void *p)
-{
-	struct flags_set *s = p;
-
-	if (s->projid != bi->bi_project) {
-		bi->bi_fields_set |= 1U << Inode_opt_project;
-		bi->bi_project = s->projid;
-	}
-
-	return bch2_inode_flags_set(trans, inode, bi, p);
-}
-
-static int bch2_ioc_fssetxattr(struct bch_fs *c,
-			       struct file *file,
-			       struct bch_inode_info *inode,
-			       struct fsxattr __user *arg)
-{
-	struct flags_set s = { .mask = map_defined(bch_flags_to_xflags) };
-	struct fsxattr fa;
-	int ret;
-
-	if (copy_from_user(&fa, arg, sizeof(fa)))
-		return -EFAULT;
-
-	s.set_projinherit = true;
-	s.projinherit = (fa.fsx_xflags & FS_XFLAG_PROJINHERIT) != 0;
-	fa.fsx_xflags &= ~FS_XFLAG_PROJINHERIT;
-
-	s.flags = map_flags_rev(bch_flags_to_xflags, fa.fsx_xflags);
-	if (fa.fsx_xflags)
-		return -EOPNOTSUPP;
-
-	if (fa.fsx_projid >= U32_MAX)
-		return -EINVAL;
-
-	/*
-	 * inode fields accessible via the xattr interface are stored with a +1
-	 * bias, so that 0 means unset:
-	 */
-	s.projid = fa.fsx_projid + 1;
-
-	ret = mnt_want_write_file(file);
-	if (ret)
-		return ret;
-
-	inode_lock(&inode->v);
-	if (!inode_owner_or_capable(file_mnt_idmap(file), &inode->v)) {
-		ret = -EACCES;
-		goto err;
-	}
-
-	mutex_lock(&inode->ei_update_lock);
-	ret   = bch2_subvol_is_ro(c, inode->ei_inum.subvol) ?:
-		bch2_set_projid(c, inode, fa.fsx_projid) ?:
-		bch2_write_inode(c, inode, fssetxattr_inode_update_fn, &s,
-			       ATTR_CTIME);
-	mutex_unlock(&inode->ei_update_lock);
-err:
-	inode_unlock(&inode->v);
-	mnt_drop_write_file(file);
-	return ret;
-}
-
 static int bch2_reinherit_attrs_fn(struct btree_trans *trans,
 				   struct bch_inode_info *inode,
 				   struct bch_inode_unpacked *bi,
@@ -558,23 +358,6 @@ long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	long ret;
 
 	switch (cmd) {
-	case FS_IOC_GETFLAGS:
-		ret = bch2_ioc_getflags(inode, (int __user *) arg);
-		break;
-
-	case FS_IOC_SETFLAGS:
-		ret = bch2_ioc_setflags(c, file, inode, (int __user *) arg);
-		break;
-
-	case FS_IOC_FSGETXATTR:
-		ret = bch2_ioc_fsgetxattr(inode, (void __user *) arg);
-		break;
-
-	case FS_IOC_FSSETXATTR:
-		ret = bch2_ioc_fssetxattr(c, file, inode,
-					  (void __user *) arg);
-		break;
-
 	case BCHFS_IOC_REINHERIT_ATTRS:
 		ret = bch2_ioc_reinherit_attrs(c, file, inode,
 					       (void __user *) arg);

fs/bcachefs/fs-ioctl.h

@@ -2,81 +2,6 @@
 #ifndef _BCACHEFS_FS_IOCTL_H
 #define _BCACHEFS_FS_IOCTL_H
 
-/* Inode flags: */
-
-/* bcachefs inode flags -> vfs inode flags: */
-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,
-};
-
-/* bcachefs inode flags -> FS_IOC_GETFLAGS: */
-static const __maybe_unused unsigned bch_flags_to_uflags[] = {
-	[__BCH_INODE_sync]		= FS_SYNC_FL,
-	[__BCH_INODE_immutable]		= FS_IMMUTABLE_FL,
-	[__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: */
-static const __maybe_unused unsigned bch_flags_to_xflags[] = {
-	[__BCH_INODE_sync]	= FS_XFLAG_SYNC,
-	[__BCH_INODE_immutable]	= FS_XFLAG_IMMUTABLE,
-	[__BCH_INODE_append]	= FS_XFLAG_APPEND,
-	[__BCH_INODE_nodump]	= FS_XFLAG_NODUMP,
-	[__BCH_INODE_noatime]	= FS_XFLAG_NOATIME,
-	//[__BCH_INODE_PROJINHERIT] = FS_XFLAG_PROJINHERIT;
-};
-
-#define set_flags(_map, _in, _out)					\
-do {									\
-	unsigned _i;							\
-									\
-	for (_i = 0; _i < ARRAY_SIZE(_map); _i++)			\
-		if ((_in) & (1 << _i))					\
-			(_out) |= _map[_i];				\
-		else							\
-			(_out) &= ~_map[_i];				\
-} while (0)
-
-#define map_flags(_map, _in)						\
-({									\
-	unsigned _out = 0;						\
-									\
-	set_flags(_map, _in, _out);					\
-	_out;								\
-})
-
-#define map_flags_rev(_map, _in)					\
-({									\
-	unsigned _i, _out = 0;						\
-									\
-	for (_i = 0; _i < ARRAY_SIZE(_map); _i++)			\
-		if ((_in) & _map[_i]) {					\
-			(_out) |= 1 << _i;				\
-			(_in) &= ~_map[_i];				\
-		}							\
-	(_out);								\
-})
-
-#define map_defined(_map)						\
-({									\
-	unsigned _in = ~0;						\
-									\
-	map_flags_rev(_map, _in);					\
-})
-
-/* Set VFS inode flags from bcachefs inode: */
-static inline void bch2_inode_flags_to_vfs(struct bch_inode_info *inode)
-{
-	set_flags(bch_flags_to_vfs, inode->ei_inode.bi_flags, inode->v.i_flags);
-}
-
 long bch2_fs_file_ioctl(struct file *, unsigned, unsigned long);
 long bch2_compat_fs_ioctl(struct file *, unsigned, unsigned long);