diff options
Diffstat (limited to 'fs/bcachefs/fs-ioctl.c')
| -rw-r--r-- | fs/bcachefs/fs-ioctl.c | 572 |
1 files changed, 572 insertions, 0 deletions
diff --git a/fs/bcachefs/fs-ioctl.c b/fs/bcachefs/fs-ioctl.c new file mode 100644 index 000000000000..6040bd3f0778 --- /dev/null +++ b/fs/bcachefs/fs-ioctl.c @@ -0,0 +1,572 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef NO_BCACHEFS_FS + +#include "bcachefs.h" +#include "chardev.h" +#include "dirent.h" +#include "fs.h" +#include "fs-common.h" +#include "fs-ioctl.h" +#include "quota.h" + +#include <linux/compat.h> +#include <linux/fsnotify.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/security.h> +#include <linux/writeback.h> + +#define FS_IOC_GOINGDOWN _IOR('X', 125, __u32) +#define FSOP_GOING_FLAGS_DEFAULT 0x0 /* going down */ +#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 (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_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_set_projid(c, inode, fa.fsx_projid); + if (ret) + goto err_unlock; + + ret = bch2_write_inode(c, inode, fssetxattr_inode_update_fn, &s, + ATTR_CTIME); +err_unlock: + 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, + void *p) +{ + struct bch_inode_info *dir = p; + + return !bch2_reinherit_attrs(bi, &dir->ei_inode); +} + +static int bch2_ioc_reinherit_attrs(struct bch_fs *c, + struct file *file, + struct bch_inode_info *src, + const char __user *name) +{ + struct bch_hash_info hash = bch2_hash_info_init(c, &src->ei_inode); + struct bch_inode_info *dst; + struct inode *vinode = NULL; + char *kname = NULL; + struct qstr qstr; + int ret = 0; + subvol_inum 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.len = ret; + qstr.name = kname; + + ret = bch2_dirent_lookup(c, inode_inum(src), &hash, &qstr, &inum); + if (ret) + 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(INODE_UPDATE_LOCK, 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(INODE_UPDATE_LOCK, 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; +} + +static int bch2_ioc_goingdown(struct bch_fs *c, u32 __user *arg) +{ + u32 flags; + int ret = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (get_user(flags, arg)) + return -EFAULT; + + bch_notice(c, "shutdown by ioctl type %u", flags); + + down_write(&c->vfs_sb->s_umount); + + switch (flags) { + case FSOP_GOING_FLAGS_DEFAULT: + ret = freeze_bdev(c->vfs_sb->s_bdev); + if (ret) + goto err; + + bch2_journal_flush(&c->journal); + c->vfs_sb->s_flags |= SB_RDONLY; + bch2_fs_emergency_read_only(c); + thaw_bdev(c->vfs_sb->s_bdev); + break; + + case FSOP_GOING_FLAGS_LOGFLUSH: + bch2_journal_flush(&c->journal); + fallthrough; + + case FSOP_GOING_FLAGS_NOLOGFLUSH: + c->vfs_sb->s_flags |= SB_RDONLY; + bch2_fs_emergency_read_only(c); + break; + default: + ret = -EINVAL; + break; + } +err: + up_write(&c->vfs_sb->s_umount); + return ret; +} + +static long __bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp, + struct bch_ioctl_subvolume arg) +{ + struct inode *dir; + struct bch_inode_info *inode; + struct user_namespace *s_user_ns; + struct dentry *dst_dentry; + struct path src_path, dst_path; + int how = LOOKUP_FOLLOW; + int error; + subvol_inum snapshot_src = { 0 }; + unsigned lookup_flags = 0; + unsigned create_flags = BCH_CREATE_SUBVOL; + + if (arg.flags & ~(BCH_SUBVOL_SNAPSHOT_CREATE| + BCH_SUBVOL_SNAPSHOT_RO)) + return -EINVAL; + + if (!(arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) && + (arg.src_ptr || + (arg.flags & BCH_SUBVOL_SNAPSHOT_RO))) + return -EINVAL; + + if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) + create_flags |= BCH_CREATE_SNAPSHOT; + + if (arg.flags & BCH_SUBVOL_SNAPSHOT_RO) + create_flags |= BCH_CREATE_SNAPSHOT_RO; + + /* why do we need this lock? */ + down_read(&c->vfs_sb->s_umount); + + if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) + sync_inodes_sb(c->vfs_sb); +retry: + if (arg.src_ptr) { + error = user_path_at(arg.dirfd, + (const char __user *)(unsigned long)arg.src_ptr, + how, &src_path); + if (error) + goto err1; + + if (src_path.dentry->d_sb->s_fs_info != c) { + path_put(&src_path); + error = -EXDEV; + goto err1; + } + + snapshot_src = inode_inum(to_bch_ei(src_path.dentry->d_inode)); + } + + dst_dentry = user_path_create(arg.dirfd, + (const char __user *)(unsigned long)arg.dst_ptr, + &dst_path, lookup_flags); + error = PTR_ERR_OR_ZERO(dst_dentry); + if (error) + goto err2; + + if (dst_dentry->d_sb->s_fs_info != c) { + error = -EXDEV; + goto err3; + } + + if (dst_dentry->d_inode) { + error = -EEXIST; + goto err3; + } + + dir = dst_path.dentry->d_inode; + if (IS_DEADDIR(dir)) { + error = -BCH_ERR_ENOENT_directory_dead; + goto err3; + } + + s_user_ns = dir->i_sb->s_user_ns; + if (!kuid_has_mapping(s_user_ns, current_fsuid()) || + !kgid_has_mapping(s_user_ns, current_fsgid())) { + error = -EOVERFLOW; + goto err3; + } + + error = inode_permission(file_mnt_idmap(filp), + dir, MAY_WRITE | MAY_EXEC); + if (error) + goto err3; + + if (!IS_POSIXACL(dir)) + arg.mode &= ~current_umask(); + + error = security_path_mkdir(&dst_path, dst_dentry, arg.mode); + if (error) + goto err3; + + if ((arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) && + !arg.src_ptr) + snapshot_src.subvol = to_bch_ei(dir)->ei_inode.bi_subvol; + + inode = __bch2_create(file_mnt_idmap(filp), to_bch_ei(dir), + dst_dentry, arg.mode|S_IFDIR, + 0, snapshot_src, create_flags); + error = PTR_ERR_OR_ZERO(inode); + if (error) + goto err3; + + d_instantiate(dst_dentry, &inode->v); + fsnotify_mkdir(dir, dst_dentry); +err3: + done_path_create(&dst_path, dst_dentry); +err2: + if (arg.src_ptr) + path_put(&src_path); + + if (retry_estale(error, lookup_flags)) { + lookup_flags |= LOOKUP_REVAL; + goto retry; + } +err1: + up_read(&c->vfs_sb->s_umount); + + return error; +} + +static long bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp, + struct bch_ioctl_subvolume arg) +{ + down_write(&c->snapshot_create_lock); + long ret = __bch2_ioctl_subvolume_create(c, filp, arg); + up_write(&c->snapshot_create_lock); + + return ret; +} + +static long bch2_ioctl_subvolume_destroy(struct bch_fs *c, struct file *filp, + struct bch_ioctl_subvolume arg) +{ + struct path path; + struct inode *dir; + int ret = 0; + + if (arg.flags) + return -EINVAL; + + ret = user_path_at(arg.dirfd, + (const char __user *)(unsigned long)arg.dst_ptr, + LOOKUP_FOLLOW, &path); + if (ret) + return ret; + + if (path.dentry->d_sb->s_fs_info != c) { + ret = -EXDEV; + goto err; + } + + dir = path.dentry->d_parent->d_inode; + + ret = __bch2_unlink(dir, path.dentry, true); + if (ret) + goto err; + + fsnotify_rmdir(dir, path.dentry); + d_delete(path.dentry); +err: + path_put(&path); + return ret; +} + +long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + struct bch_inode_info *inode = file_bch_inode(file); + struct bch_fs *c = inode->v.i_sb->s_fs_info; + 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); + break; + + case FS_IOC_GETVERSION: + ret = -ENOTTY; + break; + + case FS_IOC_SETVERSION: + ret = -ENOTTY; + break; + + case FS_IOC_GOINGDOWN: + ret = bch2_ioc_goingdown(c, (u32 __user *) arg); + break; + + case BCH_IOCTL_SUBVOLUME_CREATE: { + struct bch_ioctl_subvolume i; + + ret = copy_from_user(&i, (void __user *) arg, sizeof(i)) + ? -EFAULT + : bch2_ioctl_subvolume_create(c, file, i); + break; + } + + case BCH_IOCTL_SUBVOLUME_DESTROY: { + struct bch_ioctl_subvolume i; + + ret = copy_from_user(&i, (void __user *) arg, sizeof(i)) + ? -EFAULT + : bch2_ioctl_subvolume_destroy(c, file, i); + break; + } + + default: + ret = bch2_fs_ioctl(c, cmd, (void __user *) arg); + break; + } + + return bch2_err_class(ret); +} + +#ifdef CONFIG_COMPAT +long bch2_compat_fs_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + /* These are just misnamed, they actually get/put from/to user an int */ + switch (cmd) { + case FS_IOC_GETFLAGS: + cmd = FS_IOC_GETFLAGS; + break; + case FS_IOC32_SETFLAGS: + cmd = FS_IOC_SETFLAGS; + break; + default: + return -ENOIOCTLCMD; + } + return bch2_fs_file_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); +} +#endif + +#endif /* NO_BCACHEFS_FS */ |