bcachefs: bch2_ioc_reinherit_attrs()

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

fs/bcachefs/bcachefs_ioctl.h

@@ -307,4 +307,6 @@ struct bch_ioctl_disk_resize {
 	__u64			nbuckets;
 };
 
+#define BCHFS_IOC_REINHERIT_ATTRS	_IOR(0xbc, 14, const char __user *)
+
 #endif /* _BCACHEFS_IOCTL_H */

fs/bcachefs/fs-ioctl.c

@@ -3,6 +3,7 @@
 
 #include "bcachefs.h"
 #include "chardev.h"
+#include "dirent.h"
 #include "fs.h"
 #include "fs-ioctl.h"
 #include "quota.h"
@@ -177,6 +178,75 @@ static int bch2_ioc_fssetxattr(struct bch_fs *c,
 	return ret;
 }
 
+static int bch2_ioc_reinherit_attrs(struct bch_fs *c,
+				    struct file *file,
+				    struct bch_inode_info *src,
+				    const char __user *name)
+{
+	struct bch_inode_info *dst;
+	struct inode *vinode = NULL;
+	char *kname = NULL;
+	struct qstr qstr;
+	int ret = 0;
+	u64 inum;
+
+	kname = kmalloc(BCH_NAME_MAX + 1, GFP_KERNEL);
+	if (!kname)
+		return -ENOMEM;
+
+	ret = strncpy_from_user(kname, name, BCH_NAME_MAX);
+	if (unlikely(ret < 0))
+		goto err1;
+
+	qstr.hash_len	= ret;
+	qstr.name	= kname;
+
+	ret = -ENOENT;
+	inum = bch2_dirent_lookup(c, src->v.i_ino,
+				  &src->ei_str_hash,
+				  &qstr);
+	if (!inum)
+		goto err1;
+
+	vinode = bch2_vfs_inode_get(c, inum);
+	ret = PTR_ERR_OR_ZERO(vinode);
+	if (ret)
+		goto err1;
+
+	dst = to_bch_ei(vinode);
+
+	ret = mnt_want_write_file(file);
+	if (ret)
+		goto err2;
+
+	bch2_lock_inodes(src, dst);
+
+	if (inode_attr_changing(src, dst, Inode_opt_project)) {
+		ret = bch2_fs_quota_transfer(c, dst,
+					     src->ei_qid,
+					     1 << QTYP_PRJ,
+					     KEY_TYPE_QUOTA_PREALLOC);
+		if (ret)
+			goto err3;
+	}
+
+	ret = bch2_write_inode(c, dst, bch2_reinherit_attrs_fn, src, 0);
+err3:
+	bch2_unlock_inodes(src, dst);
+
+	/* return true if we did work */
+	if (ret >= 0)
+		ret = !ret;
+
+	mnt_drop_write_file(file);
+err2:
+	iput(vinode);
+err1:
+	kfree(kname);
+
+	return ret;
+}
+
 long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
 	struct bch_inode_info *inode = file_bch_inode(file);
@@ -193,7 +263,12 @@ long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	case FS_IOC_FSGETXATTR:
 		return bch2_ioc_fsgetxattr(inode, (void __user *) arg);
 	case FS_IOC_FSSETXATTR:
-		return bch2_ioc_fssetxattr(c, file, inode, (void __user *) arg);
+		return bch2_ioc_fssetxattr(c, file, inode,
+					   (void __user *) arg);
+
+	case BCHFS_IOC_REINHERIT_ATTRS:
+		return bch2_ioc_reinherit_attrs(c, file, inode,
+						(void __user *) arg);
 
 	case FS_IOC_GETVERSION:
 		return -ENOTTY;

fs/bcachefs/fs.c

@@ -51,30 +51,6 @@ static void journal_seq_copy(struct bch_inode_info *dst,
 	} while ((v = cmpxchg(&dst->ei_journal_seq, old, journal_seq)) != old);
 }
 
-static inline int ptrcmp(void *l, void *r)
-{
-	return (l > r) - (l < r);
-}
-
-#define __bch2_lock_inodes(_lock, ...)					\
-do {									\
-	struct bch_inode_info *a[] = { NULL, __VA_ARGS__ };		\
-	unsigned i;							\
-									\
-	bubble_sort(&a[1], ARRAY_SIZE(a) - 1 , ptrcmp);			\
-									\
-	for (i = ARRAY_SIZE(a) - 1; a[i]; --i)				\
-		if (a[i] != a[i - 1]) {					\
-			if (_lock)					\
-				mutex_lock_nested(&a[i]->ei_update_lock, i);\
-			else						\
-				mutex_unlock(&a[i]->ei_update_lock);	\
-		}							\
-} while (0)
-
-#define bch2_lock_inodes(...)	__bch2_lock_inodes(true, __VA_ARGS__)
-#define bch2_unlock_inodes(...)	__bch2_lock_inodes(false, __VA_ARGS__)
-
 static void __pagecache_lock_put(struct pagecache_lock *lock, long i)
 {
 	BUG_ON(atomic_long_read(&lock->v) == 0);
@@ -308,7 +284,7 @@ int bch2_reinherit_attrs_fn(struct bch_inode_info *inode,
 	return ret;
 }
 
-static struct inode *bch2_vfs_inode_get(struct bch_fs *c, u64 inum)
+struct inode *bch2_vfs_inode_get(struct bch_fs *c, u64 inum)
 {
 	struct bch_inode_unpacked inode_u;
 	struct bch_inode_info *inode;
@@ -393,14 +369,13 @@ __bch2_create(struct mnt_idmap *idmap,
 	bch2_inode_init(c, &inode_u, 0, 0, 0, rdev, &dir->ei_inode);
 	bch2_inode_init_owner(&inode_u, &dir->v, mode);
 
-	inode_u.bi_project = dir->ei_qid.q[QTYP_PRJ];
-
 	hash_info = bch2_hash_info_init(c, &inode_u);
 
 	if (tmpfile)
 		inode_u.bi_flags |= BCH_INODE_UNLINKED;
 
-	ret = bch2_quota_acct(c, bch_qid(&inode_u), Q_INO, 1, KEY_TYPE_QUOTA_PREALLOC);
+	ret = bch2_quota_acct(c, bch_qid(&inode_u), Q_INO, 1,
+			      KEY_TYPE_QUOTA_PREALLOC);
 	if (ret)
 		return ERR_PTR(ret);
 

fs/bcachefs/fs.h

@@ -51,6 +51,30 @@ struct bch_inode_info {
 #define to_bch_ei(_inode)					\
 	container_of_or_null(_inode, struct bch_inode_info, v)
 
+static inline int ptrcmp(void *l, void *r)
+{
+	return (l > r) - (l < r);
+}
+
+#define __bch2_lock_inodes(_lock, ...)					\
+do {									\
+	struct bch_inode_info *a[] = { NULL, __VA_ARGS__ };		\
+	unsigned i;							\
+									\
+	bubble_sort(&a[1], ARRAY_SIZE(a) - 1 , ptrcmp);			\
+									\
+	for (i = ARRAY_SIZE(a) - 1; a[i]; --i)				\
+		if (a[i] != a[i - 1]) {					\
+			if (_lock)					\
+				mutex_lock_nested(&a[i]->ei_update_lock, i);\
+			else						\
+				mutex_unlock(&a[i]->ei_update_lock);	\
+		}							\
+} while (0)
+
+#define bch2_lock_inodes(...)	__bch2_lock_inodes(true, __VA_ARGS__)
+#define bch2_unlock_inodes(...)	__bch2_lock_inodes(false, __VA_ARGS__)
+
 static inline struct bch_inode_info *file_bch_inode(struct file *file)
 {
 	return to_bch_ei(file_inode(file));
@@ -97,6 +121,8 @@ int bch2_fs_quota_transfer(struct bch_fs *,
 			   unsigned,
 			   enum quota_acct_mode);
 
+struct inode *bch2_vfs_inode_get(struct bch_fs *, u64);
+
 /* returns 0 if we want to do the update, or error is passed up */
 typedef int (*inode_set_fn)(struct bch_inode_info *,
 			    struct bch_inode_unpacked *, void *);

fs/bcachefs/inode.c

@@ -258,7 +258,8 @@ void bch2_inode_init(struct bch_fs *c, struct bch_inode_unpacked *inode_u,
 
 	/* ick */
 	inode_u->bi_flags |= c->opts.str_hash << INODE_STR_HASH_OFFSET;
-	get_random_bytes(&inode_u->bi_hash_seed, sizeof(inode_u->bi_hash_seed));
+	get_random_bytes(&inode_u->bi_hash_seed,
+			 sizeof(inode_u->bi_hash_seed));
 
 	inode_u->bi_mode	= mode;
 	inode_u->bi_uid		= uid;