diff options
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 5704 |
1 files changed, 5704 insertions, 0 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c new file mode 100644 index 000000000..72bc9d4f7 --- /dev/null +++ b/fs/btrfs/ioctl.c @@ -0,0 +1,5704 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2007 Oracle. All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/bio.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/fsnotify.h> +#include <linux/pagemap.h> +#include <linux/highmem.h> +#include <linux/time.h> +#include <linux/string.h> +#include <linux/backing-dev.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/writeback.h> +#include <linux/compat.h> +#include <linux/security.h> +#include <linux/xattr.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/blkdev.h> +#include <linux/uuid.h> +#include <linux/btrfs.h> +#include <linux/uaccess.h> +#include <linux/iversion.h> +#include <linux/fileattr.h> +#include <linux/fsverity.h> +#include <linux/sched/xacct.h> +#include <linux/io_uring/cmd.h> +#include "ctree.h" +#include "disk-io.h" +#include "export.h" +#include "transaction.h" +#include "btrfs_inode.h" +#include "volumes.h" +#include "locking.h" +#include "backref.h" +#include "send.h" +#include "dev-replace.h" +#include "props.h" +#include "sysfs.h" +#include "qgroup.h" +#include "tree-log.h" +#include "compression.h" +#include "space-info.h" +#include "block-group.h" +#include "fs.h" +#include "accessors.h" +#include "extent-tree.h" +#include "root-tree.h" +#include "defrag.h" +#include "dir-item.h" +#include "uuid-tree.h" +#include "ioctl.h" +#include "file.h" +#include "file-item.h" +#include "scrub.h" +#include "super.h" + +#ifdef CONFIG_64BIT +/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI + * structures are incorrect, as the timespec structure from userspace + * is 4 bytes too small. We define these alternatives here to teach + * the kernel about the 32-bit struct packing. + */ +struct btrfs_ioctl_timespec_32 { + __u64 sec; + __u32 nsec; +} __attribute__ ((__packed__)); + +struct btrfs_ioctl_received_subvol_args_32 { + char uuid[BTRFS_UUID_SIZE]; /* in */ + __u64 stransid; /* in */ + __u64 rtransid; /* out */ + struct btrfs_ioctl_timespec_32 stime; /* in */ + struct btrfs_ioctl_timespec_32 rtime; /* out */ + __u64 flags; /* in */ + __u64 reserved[16]; /* in */ +} __attribute__ ((__packed__)); + +#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \ + struct btrfs_ioctl_received_subvol_args_32) + +struct btrfs_ioctl_get_subvol_info_args_32 { + __u64 treeid; + char name[BTRFS_VOL_NAME_MAX + 1]; + __u64 parent_id; + __u64 dirid; + __u64 generation; + __u64 flags; + __u8 uuid[BTRFS_UUID_SIZE]; + __u8 parent_uuid[BTRFS_UUID_SIZE]; + __u8 received_uuid[BTRFS_UUID_SIZE]; + __u64 ctransid; + __u64 otransid; + __u64 stransid; + __u64 rtransid; + struct btrfs_ioctl_timespec_32 ctime; + struct btrfs_ioctl_timespec_32 otime; + struct btrfs_ioctl_timespec_32 stime; + struct btrfs_ioctl_timespec_32 rtime; + __u64 reserved[8]; +} __attribute__ ((__packed__)); + +#define BTRFS_IOC_GET_SUBVOL_INFO_32 _IOR(BTRFS_IOCTL_MAGIC, 60, \ + struct btrfs_ioctl_get_subvol_info_args_32) +#endif + +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) +struct btrfs_ioctl_send_args_32 { + __s64 send_fd; /* in */ + __u64 clone_sources_count; /* in */ + compat_uptr_t clone_sources; /* in */ + __u64 parent_root; /* in */ + __u64 flags; /* in */ + __u32 version; /* in */ + __u8 reserved[28]; /* in */ +} __attribute__ ((__packed__)); + +#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \ + struct btrfs_ioctl_send_args_32) + +struct btrfs_ioctl_encoded_io_args_32 { + compat_uptr_t iov; + compat_ulong_t iovcnt; + __s64 offset; + __u64 flags; + __u64 len; + __u64 unencoded_len; + __u64 unencoded_offset; + __u32 compression; + __u32 encryption; + __u8 reserved[64]; +}; + +#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \ + struct btrfs_ioctl_encoded_io_args_32) +#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \ + struct btrfs_ioctl_encoded_io_args_32) +#endif + +/* Mask out flags that are inappropriate for the given type of inode. */ +static unsigned int btrfs_mask_fsflags_for_type(const struct inode *inode, + unsigned int flags) +{ + if (S_ISDIR(inode->i_mode)) + return flags; + else if (S_ISREG(inode->i_mode)) + return flags & ~FS_DIRSYNC_FL; + else + return flags & (FS_NODUMP_FL | FS_NOATIME_FL); +} + +/* + * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS + * ioctl. + */ +static unsigned int btrfs_inode_flags_to_fsflags(const struct btrfs_inode *inode) +{ + unsigned int iflags = 0; + u32 flags = inode->flags; + u32 ro_flags = inode->ro_flags; + + if (flags & BTRFS_INODE_SYNC) + iflags |= FS_SYNC_FL; + if (flags & BTRFS_INODE_IMMUTABLE) + iflags |= FS_IMMUTABLE_FL; + if (flags & BTRFS_INODE_APPEND) + iflags |= FS_APPEND_FL; + if (flags & BTRFS_INODE_NODUMP) + iflags |= FS_NODUMP_FL; + if (flags & BTRFS_INODE_NOATIME) + iflags |= FS_NOATIME_FL; + if (flags & BTRFS_INODE_DIRSYNC) + iflags |= FS_DIRSYNC_FL; + if (flags & BTRFS_INODE_NODATACOW) + iflags |= FS_NOCOW_FL; + if (ro_flags & BTRFS_INODE_RO_VERITY) + iflags |= FS_VERITY_FL; + + if (flags & BTRFS_INODE_NOCOMPRESS) + iflags |= FS_NOCOMP_FL; + else if (flags & BTRFS_INODE_COMPRESS) + iflags |= FS_COMPR_FL; + + return iflags; +} + +/* + * Update inode->i_flags based on the btrfs internal flags. + */ +void btrfs_sync_inode_flags_to_i_flags(struct btrfs_inode *inode) +{ + unsigned int new_fl = 0; + + if (inode->flags & BTRFS_INODE_SYNC) + new_fl |= S_SYNC; + if (inode->flags & BTRFS_INODE_IMMUTABLE) + new_fl |= S_IMMUTABLE; + if (inode->flags & BTRFS_INODE_APPEND) + new_fl |= S_APPEND; + if (inode->flags & BTRFS_INODE_NOATIME) + new_fl |= S_NOATIME; + if (inode->flags & BTRFS_INODE_DIRSYNC) + new_fl |= S_DIRSYNC; + if (inode->ro_flags & BTRFS_INODE_RO_VERITY) + new_fl |= S_VERITY; + + set_mask_bits(&inode->vfs_inode.i_flags, + S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC | + S_VERITY, new_fl); +} + +/* + * Check if @flags are a supported and valid set of FS_*_FL flags and that + * the old and new flags are not conflicting + */ +static int check_fsflags(unsigned int old_flags, unsigned int flags) +{ + if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ + FS_NOATIME_FL | FS_NODUMP_FL | \ + FS_SYNC_FL | FS_DIRSYNC_FL | \ + FS_NOCOMP_FL | FS_COMPR_FL | + FS_NOCOW_FL)) + return -EOPNOTSUPP; + + /* COMPR and NOCOMP on new/old are valid */ + if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) + return -EINVAL; + + if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL)) + return -EINVAL; + + /* NOCOW and compression options are mutually exclusive */ + if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL))) + return -EINVAL; + if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL))) + return -EINVAL; + + return 0; +} + +static int check_fsflags_compatible(const struct btrfs_fs_info *fs_info, + unsigned int flags) +{ + if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL)) + return -EPERM; + + return 0; +} + +int btrfs_check_ioctl_vol_args_path(const struct btrfs_ioctl_vol_args *vol_args) +{ + if (memchr(vol_args->name, 0, sizeof(vol_args->name)) == NULL) + return -ENAMETOOLONG; + return 0; +} + +static int btrfs_check_ioctl_vol_args2_subvol_name(const struct btrfs_ioctl_vol_args_v2 *vol_args2) +{ + if (memchr(vol_args2->name, 0, sizeof(vol_args2->name)) == NULL) + return -ENAMETOOLONG; + return 0; +} + +/* + * Set flags/xflags from the internal inode flags. The remaining items of + * fsxattr are zeroed. + */ +int btrfs_fileattr_get(struct dentry *dentry, struct file_kattr *fa) +{ + const struct btrfs_inode *inode = BTRFS_I(d_inode(dentry)); + + fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(inode)); + return 0; +} + +int btrfs_fileattr_set(struct mnt_idmap *idmap, + struct dentry *dentry, struct file_kattr *fa) +{ + struct btrfs_inode *inode = BTRFS_I(d_inode(dentry)); + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_trans_handle *trans; + unsigned int fsflags, old_fsflags; + int ret; + const char *comp = NULL; + u32 inode_flags; + bool prop_set = false; + + if (btrfs_root_readonly(root)) + return -EROFS; + + if (fileattr_has_fsx(fa)) + return -EOPNOTSUPP; + + fsflags = btrfs_mask_fsflags_for_type(&inode->vfs_inode, fa->flags); + old_fsflags = btrfs_inode_flags_to_fsflags(inode); + ret = check_fsflags(old_fsflags, fsflags); + if (ret) + return ret; + + ret = check_fsflags_compatible(fs_info, fsflags); + if (ret) + return ret; + + inode_flags = inode->flags; + if (fsflags & FS_SYNC_FL) + inode_flags |= BTRFS_INODE_SYNC; + else + inode_flags &= ~BTRFS_INODE_SYNC; + if (fsflags & FS_IMMUTABLE_FL) + inode_flags |= BTRFS_INODE_IMMUTABLE; + else + inode_flags &= ~BTRFS_INODE_IMMUTABLE; + if (fsflags & FS_APPEND_FL) + inode_flags |= BTRFS_INODE_APPEND; + else + inode_flags &= ~BTRFS_INODE_APPEND; + if (fsflags & FS_NODUMP_FL) + inode_flags |= BTRFS_INODE_NODUMP; + else + inode_flags &= ~BTRFS_INODE_NODUMP; + if (fsflags & FS_NOATIME_FL) + inode_flags |= BTRFS_INODE_NOATIME; + else + inode_flags &= ~BTRFS_INODE_NOATIME; + + /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */ + if (!fa->flags_valid) { + /* 1 item for the inode */ + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) + return PTR_ERR(trans); + goto update_flags; + } + + if (fsflags & FS_DIRSYNC_FL) + inode_flags |= BTRFS_INODE_DIRSYNC; + else + inode_flags &= ~BTRFS_INODE_DIRSYNC; + if (fsflags & FS_NOCOW_FL) { + if (S_ISREG(inode->vfs_inode.i_mode)) { + /* + * It's safe to turn csums off here, no extents exist. + * Otherwise we want the flag to reflect the real COW + * status of the file and will not set it. + */ + if (inode->vfs_inode.i_size == 0) + inode_flags |= BTRFS_INODE_NODATACOW | + BTRFS_INODE_NODATASUM; + } else { + inode_flags |= BTRFS_INODE_NODATACOW; + } + } else { + /* We can only change NODATACOW for zero-sized regular file. */ + if (S_ISREG(inode->vfs_inode.i_mode) && (inode->vfs_inode.i_size == 0)) { + inode_flags &= ~BTRFS_INODE_NODATACOW; + /* + * There is currently no way to change NODATASUM flag + * through fileattr API. If we unconditionally keep the + * current NODATASUM flag, chattr +C then chattr -C will + * keep the NODATASUM flag, and no way to remove that + * flag. + * + * So respect the current mount option for NODATASUM flag. + */ + if (!btrfs_test_opt(fs_info, NODATASUM)) + inode_flags &= ~BTRFS_INODE_NODATASUM; + } else if (!S_ISREG(inode->vfs_inode.i_mode)) { + inode_flags &= ~BTRFS_INODE_NODATACOW; + } + } + + /* + * The COMPRESS flag can only be changed by users, while the NOCOMPRESS + * flag may be changed automatically if compression code won't make + * things smaller. + */ + if (fsflags & FS_NOCOMP_FL) { + inode_flags &= ~BTRFS_INODE_COMPRESS; + inode_flags |= BTRFS_INODE_NOCOMPRESS; + } else if (fsflags & FS_COMPR_FL) { + + if (IS_SWAPFILE(&inode->vfs_inode)) + return -ETXTBSY; + + inode_flags |= BTRFS_INODE_COMPRESS; + inode_flags &= ~BTRFS_INODE_NOCOMPRESS; + + comp = btrfs_compress_type2str(fs_info->compress_type); + if (!comp || comp[0] == 0) + comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB); + } else { + inode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); + } + + /* + * 1 for inode item + * 1 for property + */ + trans = btrfs_start_transaction(root, 2); + if (IS_ERR(trans)) + return PTR_ERR(trans); + + if (comp) { + ret = btrfs_set_prop(trans, inode, "btrfs.compression", + comp, strlen(comp), 0); + if (ret) + goto out_end_trans; + prop_set = true; + } else { + ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL, 0, 0); + prop_set = (ret == 0); + /* If ret == -ENODATA ignore and proceed to update inode item. */ + if (ret && ret != -ENODATA) + goto out_end_trans; + } + +update_flags: + inode->flags = inode_flags; + btrfs_update_inode_mapping_flags(inode); + btrfs_sync_inode_flags_to_i_flags(inode); + inode_inc_iversion(&inode->vfs_inode); + inode_set_ctime_current(&inode->vfs_inode); + ret = btrfs_update_inode(trans, inode); + /* + * If we set a property or deleted one, we must abort if we fail to + * update the inode, to avoid persisting an inconsistent state. + */ + if (unlikely(ret && prop_set)) + btrfs_abort_transaction(trans, ret); + + out_end_trans: + btrfs_end_transaction(trans); + return ret; +} + +static int btrfs_ioctl_getversion(const struct inode *inode, int __user *arg) +{ + return put_user(inode->i_generation, arg); +} + +static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_device *device; + struct fstrim_range range; + u64 minlen = ULLONG_MAX; + u64 num_devices = 0; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* + * btrfs_trim_block_group() depends on space cache, which is not + * available in zoned filesystem. So, disallow fitrim on a zoned + * filesystem for now. + */ + if (btrfs_is_zoned(fs_info)) + return -EOPNOTSUPP; + + /* + * If the fs is mounted with nologreplay, which requires it to be + * mounted in RO mode as well, we can not allow discard on free space + * inside block groups, because log trees refer to extents that are not + * pinned in a block group's free space cache (pinning the extents is + * precisely the first phase of replaying a log tree). + */ + if (btrfs_test_opt(fs_info, NOLOGREPLAY)) + return -EROFS; + + rcu_read_lock(); + list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, + dev_list) { + if (!device->bdev || !bdev_max_discard_sectors(device->bdev)) + continue; + num_devices++; + minlen = min_t(u64, bdev_discard_granularity(device->bdev), + minlen); + } + rcu_read_unlock(); + + if (!num_devices) + return -EOPNOTSUPP; + if (copy_from_user(&range, arg, sizeof(range))) + return -EFAULT; + + /* + * NOTE: Don't truncate the range using super->total_bytes. Bytenr of + * block group is in the logical address space, which can be any + * sectorsize aligned bytenr in the range [0, U64_MAX]. + */ + if (range.len < fs_info->sectorsize) + return -EINVAL; + + range.minlen = max(range.minlen, minlen); + ret = btrfs_trim_fs(fs_info, &range); + + if (copy_to_user(arg, &range, sizeof(range))) + return -EFAULT; + + return ret; +} + +/* + * Calculate the number of transaction items to reserve for creating a subvolume + * or snapshot, not including the inode, directory entries, or parent directory. + */ +static unsigned int create_subvol_num_items(const struct btrfs_qgroup_inherit *inherit) +{ + /* + * 1 to add root block + * 1 to add root item + * 1 to add root ref + * 1 to add root backref + * 1 to add UUID item + * 1 to add qgroup info + * 1 to add qgroup limit + * + * Ideally the last two would only be accounted if qgroups are enabled, + * but that can change between now and the time we would insert them. + */ + unsigned int num_items = 7; + + if (inherit) { + /* 2 to add qgroup relations for each inherited qgroup */ + num_items += 2 * inherit->num_qgroups; + } + return num_items; +} + +static noinline int create_subvol(struct mnt_idmap *idmap, + struct inode *dir, struct dentry *dentry, + struct btrfs_qgroup_inherit *inherit) +{ + struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); + struct btrfs_trans_handle *trans; + struct btrfs_key key; + struct btrfs_root_item AUTO_KFREE(root_item); + struct btrfs_inode_item *inode_item; + struct extent_buffer *leaf; + struct btrfs_root *root = BTRFS_I(dir)->root; + struct btrfs_root *new_root; + struct btrfs_block_rsv block_rsv; + struct timespec64 cur_time = current_time(dir); + struct btrfs_new_inode_args new_inode_args = { + .dir = dir, + .dentry = dentry, + .subvol = true, + }; + unsigned int trans_num_items; + int ret; + dev_t anon_dev; + u64 objectid; + u64 qgroup_reserved = 0; + + root_item = kzalloc(sizeof(*root_item), GFP_KERNEL); + if (!root_item) + return -ENOMEM; + + ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid); + if (ret) + return ret; + + /* + * Don't create subvolume whose level is not zero. Or qgroup will be + * screwed up since it assumes subvolume qgroup's level to be 0. + */ + if (btrfs_qgroup_level(objectid)) + return -ENOSPC; + + ret = get_anon_bdev(&anon_dev); + if (ret < 0) + return ret; + + new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir); + if (!new_inode_args.inode) { + ret = -ENOMEM; + goto out_anon_dev; + } + ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items); + if (ret) + goto out_inode; + trans_num_items += create_subvol_num_items(inherit); + + btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); + ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, + trans_num_items, false); + if (ret) + goto out_new_inode_args; + qgroup_reserved = block_rsv.qgroup_rsv_reserved; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_release_rsv; + } + btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); + qgroup_reserved = 0; + trans->block_rsv = &block_rsv; + trans->bytes_reserved = block_rsv.size; + + ret = btrfs_qgroup_inherit(trans, 0, objectid, btrfs_root_id(root), inherit); + if (ret) + goto out; + + leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0, + 0, BTRFS_NESTING_NORMAL); + if (IS_ERR(leaf)) { + ret = PTR_ERR(leaf); + goto out; + } + + btrfs_mark_buffer_dirty(trans, leaf); + + inode_item = &root_item->inode; + btrfs_set_stack_inode_generation(inode_item, 1); + btrfs_set_stack_inode_size(inode_item, 3); + btrfs_set_stack_inode_nlink(inode_item, 1); + btrfs_set_stack_inode_nbytes(inode_item, + fs_info->nodesize); + btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); + + btrfs_set_root_flags(root_item, 0); + btrfs_set_root_limit(root_item, 0); + btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); + + btrfs_set_root_bytenr(root_item, leaf->start); + btrfs_set_root_generation(root_item, trans->transid); + btrfs_set_root_level(root_item, 0); + btrfs_set_root_refs(root_item, 1); + btrfs_set_root_used(root_item, leaf->len); + btrfs_set_root_last_snapshot(root_item, 0); + + btrfs_set_root_generation_v2(root_item, + btrfs_root_generation(root_item)); + generate_random_guid(root_item->uuid); + btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec); + btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec); + root_item->ctime = root_item->otime; + btrfs_set_root_ctransid(root_item, trans->transid); + btrfs_set_root_otransid(root_item, trans->transid); + + btrfs_tree_unlock(leaf); + + btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID); + + key.objectid = objectid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = 0; + ret = btrfs_insert_root(trans, fs_info->tree_root, &key, + root_item); + if (ret) { + int ret2; + + /* + * Since we don't abort the transaction in this case, free the + * tree block so that we don't leak space and leave the + * filesystem in an inconsistent state (an extent item in the + * extent tree with a backreference for a root that does not + * exists). + */ + btrfs_tree_lock(leaf); + btrfs_clear_buffer_dirty(trans, leaf); + btrfs_tree_unlock(leaf); + ret2 = btrfs_free_tree_block(trans, objectid, leaf, 0, 1); + if (unlikely(ret2 < 0)) + btrfs_abort_transaction(trans, ret2); + free_extent_buffer(leaf); + goto out; + } + + free_extent_buffer(leaf); + leaf = NULL; + + new_root = btrfs_get_new_fs_root(fs_info, objectid, &anon_dev); + if (IS_ERR(new_root)) { + ret = PTR_ERR(new_root); + btrfs_abort_transaction(trans, ret); + goto out; + } + /* anon_dev is owned by new_root now. */ + anon_dev = 0; + BTRFS_I(new_inode_args.inode)->root = new_root; + /* ... and new_root is owned by new_inode_args.inode now. */ + + ret = btrfs_record_root_in_trans(trans, new_root); + if (unlikely(ret)) { + btrfs_abort_transaction(trans, ret); + goto out; + } + + ret = btrfs_uuid_tree_add(trans, root_item->uuid, + BTRFS_UUID_KEY_SUBVOL, objectid); + if (unlikely(ret)) { + btrfs_abort_transaction(trans, ret); + goto out; + } + + btrfs_record_new_subvolume(trans, BTRFS_I(dir)); + + ret = btrfs_create_new_inode(trans, &new_inode_args); + if (unlikely(ret)) { + btrfs_abort_transaction(trans, ret); + goto out; + } + + /* + * Subvolumes have orphans cleaned on first dentry lookup. A new + * subvolume cannot have any orphans, so we should set the bit before we + * add the subvolume dentry to the dentry cache, so that it is in the + * same state as a subvolume after first lookup. + */ + set_bit(BTRFS_ROOT_ORPHAN_CLEANUP, &new_root->state); + d_instantiate_new(dentry, new_inode_args.inode); + new_inode_args.inode = NULL; + +out: + trans->block_rsv = NULL; + trans->bytes_reserved = 0; + btrfs_end_transaction(trans); +out_release_rsv: + btrfs_block_rsv_release(fs_info, &block_rsv, (u64)-1, NULL); + if (qgroup_reserved) + btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved); +out_new_inode_args: + btrfs_new_inode_args_destroy(&new_inode_args); +out_inode: + iput(new_inode_args.inode); +out_anon_dev: + if (anon_dev) + free_anon_bdev(anon_dev); + + return ret; +} + +static int create_snapshot(struct btrfs_root *root, struct inode *dir, + struct dentry *dentry, bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); + struct inode *inode; + struct btrfs_pending_snapshot AUTO_KFREE(pending_snapshot); + unsigned int trans_num_items; + struct btrfs_trans_handle *trans; + struct btrfs_block_rsv *block_rsv; + u64 qgroup_reserved = 0; + int ret; + + /* We do not support snapshotting right now. */ + if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { + btrfs_warn(fs_info, + "extent tree v2 doesn't support snapshotting yet"); + return -EOPNOTSUPP; + } + + if (btrfs_root_refs(&root->root_item) == 0) + return -ENOENT; + + if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state)) + return -EINVAL; + + if (atomic_read(&root->nr_swapfiles)) { + btrfs_warn(fs_info, + "cannot snapshot subvolume with active swapfile"); + return -ETXTBSY; + } + + pending_snapshot = kzalloc_obj(*pending_snapshot); + if (!pending_snapshot) + return -ENOMEM; + + ret = get_anon_bdev(&pending_snapshot->anon_dev); + if (ret < 0) + goto free_pending; + pending_snapshot->root_item = kzalloc_obj(struct btrfs_root_item); + pending_snapshot->path = btrfs_alloc_path(); + if (!pending_snapshot->root_item || !pending_snapshot->path) { + ret = -ENOMEM; + goto free_pending; + } + + block_rsv = &pending_snapshot->block_rsv; + btrfs_init_block_rsv(block_rsv, BTRFS_BLOCK_RSV_TEMP); + /* + * 1 to add dir item + * 1 to add dir index + * 1 to update parent inode item + */ + trans_num_items = create_subvol_num_items(inherit) + 3; + ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, block_rsv, + trans_num_items, false); + if (ret) + goto free_pending; + qgroup_reserved = block_rsv->qgroup_rsv_reserved; + + pending_snapshot->dentry = dentry; + pending_snapshot->root = root; + pending_snapshot->readonly = readonly; + pending_snapshot->dir = BTRFS_I(dir); + pending_snapshot->inherit = inherit; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto fail; + } + ret = btrfs_record_root_in_trans(trans, BTRFS_I(dir)->root); + if (ret) { + btrfs_end_transaction(trans); + goto fail; + } + btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); + qgroup_reserved = 0; + + trans->pending_snapshot = pending_snapshot; + + ret = btrfs_commit_transaction(trans); + if (ret) + goto fail; + + ret = pending_snapshot->error; + if (ret) + goto fail; + + ret = btrfs_orphan_cleanup(pending_snapshot->snap); + if (ret) + goto fail; + + inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto fail; + } + + d_instantiate(dentry, inode); + ret = 0; + pending_snapshot->anon_dev = 0; +fail: + /* Prevent double freeing of anon_dev */ + if (ret && pending_snapshot->snap) + pending_snapshot->snap->anon_dev = 0; + btrfs_put_root(pending_snapshot->snap); + btrfs_block_rsv_release(fs_info, block_rsv, (u64)-1, NULL); + if (qgroup_reserved) + btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved); +free_pending: + if (pending_snapshot->anon_dev) + free_anon_bdev(pending_snapshot->anon_dev); + kfree(pending_snapshot->root_item); + btrfs_free_path(pending_snapshot->path); + + return ret; +} + +/* + * Create a new subvolume below @parent. This is largely modeled after + * sys_mkdirat and vfs_mkdir, but we only do a single component lookup + * inside this filesystem so it's quite a bit simpler. + */ +static noinline int btrfs_mksubvol(struct dentry *parent, + struct mnt_idmap *idmap, + struct qstr *qname, struct btrfs_root *snap_src, + bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + struct inode *dir = d_inode(parent); + struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); + struct dentry *dentry; + struct fscrypt_str name_str = FSTR_INIT((char *)qname->name, qname->len); + int ret; + + dentry = start_creating_killable(idmap, parent, qname); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + ret = may_create_dentry(idmap, dir, dentry); + if (ret) + goto out_dput; + + /* + * even if this name doesn't exist, we may get hash collisions. + * check for them now when we can safely fail + */ + ret = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, dir->i_ino, &name_str); + if (ret) + goto out_dput; + + down_read(&fs_info->subvol_sem); + + if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0) + goto out_up_read; + + if (snap_src) + ret = create_snapshot(snap_src, dir, dentry, readonly, inherit); + else + ret = create_subvol(idmap, dir, dentry, inherit); + + if (!ret) + fsnotify_mkdir(dir, dentry); +out_up_read: + up_read(&fs_info->subvol_sem); +out_dput: + end_creating(dentry); + return ret; +} + +static noinline int btrfs_mksnapshot(struct dentry *parent, + struct mnt_idmap *idmap, + struct qstr *qname, + struct btrfs_root *root, + bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + int ret; + + /* + * Force new buffered writes to reserve space even when NOCOW is + * possible. This is to avoid later writeback (running delalloc) to + * fallback to COW mode and unexpectedly fail with ENOSPC. + */ + btrfs_drew_read_lock(&root->snapshot_lock); + + ret = btrfs_start_delalloc_snapshot(root, false); + if (ret) + goto out; + + /* + * All previous writes have started writeback in NOCOW mode, so now + * we force future writes to fallback to COW mode during snapshot + * creation. + */ + atomic_inc(&root->snapshot_force_cow); + + btrfs_wait_ordered_extents(root, U64_MAX, NULL); + + ret = btrfs_mksubvol(parent, idmap, qname, root, readonly, inherit); + + atomic_dec(&root->snapshot_force_cow); +out: + btrfs_drew_read_unlock(&root->snapshot_lock); + return ret; +} + +/* + * Try to start exclusive operation @type or cancel it if it's running. + * + * Return: + * 0 - normal mode, newly claimed op started + * >0 - normal mode, something else is running, + * return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space + * ECANCELED - cancel mode, successful cancel + * ENOTCONN - cancel mode, operation not running anymore + */ +static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info, + enum btrfs_exclusive_operation type, bool cancel) +{ + if (!cancel) { + /* Start normal op */ + if (!btrfs_exclop_start(fs_info, type)) + return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + /* Exclusive operation is now claimed */ + return 0; + } + + /* Cancel running op */ + if (btrfs_exclop_start_try_lock(fs_info, type)) { + /* + * This blocks any exclop finish from setting it to NONE, so we + * request cancellation. Either it runs and we will wait for it, + * or it has finished and no waiting will happen. + */ + atomic_inc(&fs_info->reloc_cancel_req); + btrfs_exclop_start_unlock(fs_info); + + if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags)) + wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING, + TASK_INTERRUPTIBLE); + + return -ECANCELED; + } + + /* Something else is running or none */ + return -ENOTCONN; +} + +static noinline int btrfs_ioctl_resize(struct file *file, + void __user *arg) +{ + BTRFS_DEV_LOOKUP_ARGS(args); + struct btrfs_root *root = BTRFS_I(file_inode(file))->root; + struct btrfs_fs_info *fs_info = root->fs_info; + u64 new_size; + u64 old_size; + u64 devid = 1; + struct btrfs_ioctl_vol_args AUTO_KFREE(vol_args); + struct btrfs_device *device = NULL; + char *sizestr; + char *devstr = NULL; + int ret = 0; + int mod = 0; + bool cancel; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + /* + * Read the arguments before checking exclusivity to be able to + * distinguish regular resize and cancel + */ + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto out_drop; + } + ret = btrfs_check_ioctl_vol_args_path(vol_args); + if (ret < 0) + goto out_drop; + + sizestr = vol_args->name; + cancel = (strcmp("cancel", sizestr) == 0); + ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel); + if (ret) + goto out_drop; + /* Exclusive operation is now claimed */ + + devstr = strchr(sizestr, ':'); + if (devstr) { + sizestr = devstr + 1; + *devstr = '\0'; + devstr = vol_args->name; + ret = kstrtoull(devstr, 10, &devid); + if (ret) + goto out_finish; + if (!devid) { + ret = -EINVAL; + goto out_finish; + } + btrfs_info(fs_info, "resizing devid %llu", devid); + } + + args.devid = devid; + device = btrfs_find_device(fs_info->fs_devices, &args); + if (!device) { + btrfs_info(fs_info, "resizer unable to find device %llu", + devid); + ret = -ENODEV; + goto out_finish; + } + + if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { + btrfs_info(fs_info, + "resizer unable to apply on readonly device %llu", + devid); + ret = -EPERM; + goto out_finish; + } + + if (!strcmp(sizestr, "max")) + new_size = bdev_nr_bytes(device->bdev); + else { + char *retptr; + + if (sizestr[0] == '-') { + mod = -1; + sizestr++; + } else if (sizestr[0] == '+') { + mod = 1; + sizestr++; + } + new_size = memparse(sizestr, &retptr); + if (*retptr != '\0' || new_size == 0) { + ret = -EINVAL; + goto out_finish; + } + } + + if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { + ret = -EPERM; + goto out_finish; + } + + old_size = btrfs_device_get_total_bytes(device); + + if (mod < 0) { + if (new_size > old_size) { + ret = -EINVAL; + goto out_finish; + } + new_size = old_size - new_size; + } else if (mod > 0) { + if (new_size > ULLONG_MAX - old_size) { + ret = -ERANGE; + goto out_finish; + } + new_size = old_size + new_size; + } + + if (new_size < SZ_256M) { + ret = -EINVAL; + goto out_finish; + } + if (new_size > bdev_nr_bytes(device->bdev)) { + ret = -EFBIG; + goto out_finish; + } + + new_size = round_down(new_size, fs_info->sectorsize); + + if (new_size > old_size) { + struct btrfs_trans_handle *trans; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_finish; + } + ret = btrfs_grow_device(trans, device, new_size); + btrfs_commit_transaction(trans); + } else if (new_size < old_size) { + ret = btrfs_shrink_device(device, new_size); + } /* equal, nothing need to do */ + + if (ret == 0 && new_size != old_size) + btrfs_info(fs_info, + "resize device %s (devid %llu) from %llu to %llu", + btrfs_dev_name(device), device->devid, + old_size, new_size); +out_finish: + btrfs_exclop_finish(fs_info); +out_drop: + mnt_drop_write_file(file); + return ret; +} + +static noinline int __btrfs_ioctl_snap_create(struct file *file, + const char *name, unsigned long fd, bool subvol, + bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + int ret; + struct qstr qname = QSTR(name); + struct mnt_idmap *idmap = file_mnt_idmap(file); + + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (strchr(name, '/')) { + ret = -EINVAL; + goto out_drop_write; + } + + if (qname.name[0] == '.' && + (qname.len == 1 || (qname.name[1] == '.' && qname.len == 2))) { + ret = -EEXIST; + goto out_drop_write; + } + + if (subvol) { + ret = btrfs_mksubvol(file_dentry(file), idmap, &qname, NULL, + readonly, inherit); + } else { + CLASS(fd, src)(fd); + struct inode *src_inode; + if (fd_empty(src)) { + ret = -EINVAL; + goto out_drop_write; + } + + src_inode = file_inode(fd_file(src)); + if (src_inode->i_sb != file_inode(file)->i_sb) { + btrfs_info(BTRFS_I(file_inode(file))->root->fs_info, + "Snapshot src from another FS"); + ret = -EXDEV; + } else if (!inode_owner_or_capable(idmap, src_inode)) { + /* + * Subvolume creation is not restricted, but snapshots + * are limited to own subvolumes only + */ + ret = -EPERM; + } else if (btrfs_ino(BTRFS_I(src_inode)) != BTRFS_FIRST_FREE_OBJECTID) { + /* + * Snapshots must be made with the src_inode referring + * to the subvolume inode, otherwise the permission + * checking above is useless because we may have + * permission on a lower directory but not the subvol + * itself. + */ + ret = -EINVAL; + } else { + ret = btrfs_mksnapshot(file_dentry(file), idmap, &qname, + BTRFS_I(src_inode)->root, + readonly, inherit); + } + } +out_drop_write: + mnt_drop_write_file(file); + return ret; +} + +static noinline int btrfs_ioctl_snap_create(struct file *file, + void __user *arg, bool subvol) +{ + struct btrfs_ioctl_vol_args AUTO_KFREE(vol_args); + int ret; + + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + ret = btrfs_check_ioctl_vol_args_path(vol_args); + if (ret < 0) + return ret; + + return __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd, subvol, + false, NULL); +} + +static noinline int btrfs_ioctl_snap_create_v2(struct file *file, + void __user *arg, bool subvol) +{ + struct btrfs_ioctl_vol_args_v2 AUTO_KFREE(vol_args); + struct btrfs_qgroup_inherit AUTO_KFREE(inherit); + int ret; + bool readonly = false; + + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args); + if (ret < 0) + return ret; + + if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) + return -EOPNOTSUPP; + + if (vol_args->flags & BTRFS_SUBVOL_RDONLY) + readonly = true; + if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { + struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file)); + + if (vol_args->size < sizeof(*inherit) || vol_args->size > PAGE_SIZE) + return -EINVAL; + + inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); + if (IS_ERR(inherit)) { + return PTR_ERR(inherit); + } + + ret = btrfs_qgroup_check_inherit(fs_info, inherit, vol_args->size); + if (ret < 0) + return ret; + } + + return __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd, subvol, + readonly, inherit); +} + +static noinline int btrfs_ioctl_subvol_getflags(struct btrfs_inode *inode, + void __user *arg) +{ + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + int ret = 0; + u64 flags = 0; + + if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) + return -EINVAL; + + down_read(&fs_info->subvol_sem); + if (btrfs_root_readonly(root)) + flags |= BTRFS_SUBVOL_RDONLY; + up_read(&fs_info->subvol_sem); + + if (copy_to_user(arg, &flags, sizeof(flags))) + ret = -EFAULT; + + return ret; +} + +static noinline int btrfs_ioctl_subvol_setflags(struct file *file, + void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_trans_handle *trans; + u64 root_flags; + u64 flags; + int ret; + + if (!inode_owner_or_capable(file_mnt_idmap(file), inode)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { + ret = -EINVAL; + goto out_drop_write; + } + + if (copy_from_user(&flags, arg, sizeof(flags))) { + ret = -EFAULT; + goto out_drop_write; + } + + if (flags & ~BTRFS_SUBVOL_RDONLY) { + ret = -EOPNOTSUPP; + goto out_drop_write; + } + + down_write(&fs_info->subvol_sem); + + /* nothing to do */ + if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) + goto out_drop_sem; + + root_flags = btrfs_root_flags(&root->root_item); + if (flags & BTRFS_SUBVOL_RDONLY) { + btrfs_set_root_flags(&root->root_item, + root_flags | BTRFS_ROOT_SUBVOL_RDONLY); + } else { + /* + * Block RO -> RW transition if this subvolume is involved in + * send + */ + spin_lock(&root->root_item_lock); + if (root->send_in_progress == 0) { + btrfs_set_root_flags(&root->root_item, + root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); + spin_unlock(&root->root_item_lock); + } else { + spin_unlock(&root->root_item_lock); + btrfs_warn(fs_info, + "Attempt to set subvolume %llu read-write during send", + btrfs_root_id(root)); + ret = -EPERM; + goto out_drop_sem; + } + } + + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_reset; + } + + ret = btrfs_update_root(trans, fs_info->tree_root, + &root->root_key, &root->root_item); + if (ret < 0) { + btrfs_end_transaction(trans); + goto out_reset; + } + + ret = btrfs_commit_transaction(trans); + +out_reset: + if (ret) + btrfs_set_root_flags(&root->root_item, root_flags); +out_drop_sem: + up_write(&fs_info->subvol_sem); +out_drop_write: + mnt_drop_write_file(file); + return ret; +} + +static noinline bool key_in_sk(const struct btrfs_key *key, + const struct btrfs_ioctl_search_key *sk) +{ + struct btrfs_key test; + int ret; + + test.objectid = sk->min_objectid; + test.type = sk->min_type; + test.offset = sk->min_offset; + + ret = btrfs_comp_cpu_keys(key, &test); + if (ret < 0) + return false; + + test.objectid = sk->max_objectid; + test.type = sk->max_type; + test.offset = sk->max_offset; + + ret = btrfs_comp_cpu_keys(key, &test); + if (ret > 0) + return false; + return true; +} + +static noinline int copy_to_sk(struct btrfs_path *path, + struct btrfs_key *key, + const struct btrfs_ioctl_search_key *sk, + u64 *buf_size, + char __user *ubuf, + unsigned long *sk_offset, + int *num_found) +{ + u64 found_transid; + struct extent_buffer *leaf; + struct btrfs_ioctl_search_header sh; + struct btrfs_key test; + unsigned long item_off; + unsigned long item_len; + int nritems; + int i; + int slot; + int ret = 0; + + leaf = path->nodes[0]; + slot = path->slots[0]; + nritems = btrfs_header_nritems(leaf); + + if (btrfs_header_generation(leaf) > sk->max_transid) { + i = nritems; + goto advance_key; + } + found_transid = btrfs_header_generation(leaf); + + for (i = slot; i < nritems; i++) { + item_off = btrfs_item_ptr_offset(leaf, i); + item_len = btrfs_item_size(leaf, i); + + btrfs_item_key_to_cpu(leaf, key, i); + if (!key_in_sk(key, sk)) + continue; + + if (sizeof(sh) + item_len > *buf_size) { + if (*num_found) + return 1; + + /* + * return one empty item back for v1, which does not + * handle -EOVERFLOW + */ + + *buf_size = sizeof(sh) + item_len; + item_len = 0; + ret = -EOVERFLOW; + } + + if (sizeof(sh) + item_len + *sk_offset > *buf_size) + return 1; + + sh.objectid = key->objectid; + sh.type = key->type; + sh.offset = key->offset; + sh.len = item_len; + sh.transid = found_transid; + + /* + * Copy search result header. If we fault then loop again so we + * can fault in the pages and -EFAULT there if there's a + * problem. Otherwise we'll fault and then copy the buffer in + * properly this next time through + */ + if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) + return 0; + + *sk_offset += sizeof(sh); + + if (item_len) { + char __user *up = ubuf + *sk_offset; + /* + * Copy the item, same behavior as above, but reset the + * * sk_offset so we copy the full thing again. + */ + if (read_extent_buffer_to_user_nofault(leaf, up, + item_off, item_len)) { + *sk_offset -= sizeof(sh); + return 0; + } + + *sk_offset += item_len; + } + (*num_found)++; + + /* -EOVERFLOW from above. */ + if (ret) + return ret; + + if (*num_found >= sk->nr_items) + return 1; + } +advance_key: + ret = 0; + test.objectid = sk->max_objectid; + test.type = sk->max_type; + test.offset = sk->max_offset; + if (btrfs_comp_cpu_keys(key, &test) >= 0) + ret = 1; + else if (key->offset < (u64)-1) + key->offset++; + else if (key->type < (u8)-1) { + key->offset = 0; + key->type++; + } else if (key->objectid < (u64)-1) { + key->offset = 0; + key->type = 0; + key->objectid++; + } else + ret = 1; + + /* + * 0: all items from this leaf copied, continue with next + * 1: * more items can be copied, but unused buffer is too small + * * all items were found + * Either way, it will stops the loop which iterates to the next + * leaf + * -EOVERFLOW: item was to large for buffer + * -EFAULT: could not copy extent buffer back to userspace + */ + return ret; +} + +static noinline int search_ioctl(struct btrfs_root *root, + struct btrfs_ioctl_search_key *sk, + u64 *buf_size, + char __user *ubuf) +{ + struct btrfs_fs_info *info = root->fs_info; + struct btrfs_key key; + BTRFS_PATH_AUTO_FREE(path); + int ret; + int num_found = 0; + unsigned long sk_offset = 0; + + if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) { + *buf_size = sizeof(struct btrfs_ioctl_search_header); + return -EOVERFLOW; + } + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + if (sk->tree_id == 0) { + /* Search the root that we got passed. */ + root = btrfs_grab_root(root); + } else { + /* Look up the root from the arguments. */ + root = btrfs_get_fs_root(info, sk->tree_id, true); + if (IS_ERR(root)) + return PTR_ERR(root); + } + + key.objectid = sk->min_objectid; + key.type = sk->min_type; + key.offset = sk->min_offset; + + while (1) { + /* + * Ensure that the whole user buffer is faulted in at sub-page + * granularity, otherwise the loop may live-lock. + */ + if (fault_in_subpage_writeable(ubuf + sk_offset, *buf_size - sk_offset)) { + ret = -EFAULT; + break; + } + + ret = btrfs_search_forward(root, &key, path, sk->min_transid); + if (ret) + break; + + ret = copy_to_sk(path, &key, sk, buf_size, ubuf, + &sk_offset, &num_found); + btrfs_release_path(path); + if (ret) + break; + + } + /* Normalize return values from btrfs_search_forward() and copy_to_sk(). */ + if (ret > 0) + ret = 0; + + sk->nr_items = num_found; + btrfs_put_root(root); + return ret; +} + +static noinline int btrfs_ioctl_tree_search(struct btrfs_root *root, + void __user *argp) +{ + struct btrfs_ioctl_search_args __user *uargs = argp; + struct btrfs_ioctl_search_key sk; + int ret; + u64 buf_size; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (copy_from_user(&sk, &uargs->key, sizeof(sk))) + return -EFAULT; + + buf_size = sizeof(uargs->buf); + + ret = search_ioctl(root, &sk, &buf_size, uargs->buf); + + /* + * In the origin implementation an overflow is handled by returning a + * search header with a len of zero, so reset ret. + */ + if (ret == -EOVERFLOW) + ret = 0; + + if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk))) + ret = -EFAULT; + return ret; +} + +static noinline int btrfs_ioctl_tree_search_v2(struct btrfs_root *root, + void __user *argp) +{ + struct btrfs_ioctl_search_args_v2 __user *uarg = argp; + struct btrfs_ioctl_search_args_v2 args; + int ret; + u64 buf_size; + const u64 buf_limit = SZ_16M; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* copy search header and buffer size */ + if (copy_from_user(&args, uarg, sizeof(args))) + return -EFAULT; + + buf_size = args.buf_size; + + /* limit result size to 16MB */ + if (buf_size > buf_limit) + buf_size = buf_limit; + + ret = search_ioctl(root, &args.key, &buf_size, + (char __user *)(&uarg->buf[0])); + if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key))) + ret = -EFAULT; + else if (ret == -EOVERFLOW && + copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size))) + ret = -EFAULT; + + return ret; +} + +/* + * Search for an INODE_REF in a 'root' tree which identifies the path name of + * 'dirid'. When found, it sets 'name' with the path name. + */ +static noinline int btrfs_search_path_in_tree(struct btrfs_root *root, u64 dirid, char *name) +{ + struct btrfs_key key; + char *ptr; + int ret = -1; + int slot; + int len; + int total_len = 0; + struct btrfs_inode_ref *iref; + struct extent_buffer *l; + BTRFS_PATH_AUTO_FREE(path); + + if (dirid == BTRFS_FIRST_FREE_OBJECTID) { + name[0]='\0'; + return 0; + } + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1]; + + key.objectid = dirid; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + + while (1) { + ret = btrfs_search_backwards(root, &key, path); + if (ret < 0) + return ret; + else if (ret > 0) + return -ENOENT; + + l = path->nodes[0]; + slot = path->slots[0]; + + iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); + len = btrfs_inode_ref_name_len(l, iref); + ptr -= len + 1; + total_len += len + 1; + if (ptr < name) + return -ENAMETOOLONG; + + *(ptr + len) = '/'; + read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len); + + if (key.offset == BTRFS_FIRST_FREE_OBJECTID) + break; + + btrfs_release_path(path); + key.objectid = key.offset; + key.offset = (u64)-1; + dirid = key.objectid; + } + memmove(name, ptr, total_len); + name[total_len] = '\0'; + + return 0; +} + +static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap, + struct inode *inode, + struct btrfs_ioctl_ino_lookup_user_args *args) +{ + struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; + u64 upper_limit = btrfs_ino(BTRFS_I(inode)); + u64 treeid = btrfs_root_id(BTRFS_I(inode)->root); + u64 dirid = args->dirid; + unsigned long item_off; + unsigned long item_len; + struct btrfs_inode_ref *iref; + struct btrfs_root_ref *rref; + struct btrfs_root *root = NULL; + BTRFS_PATH_AUTO_FREE(path); + struct btrfs_key key; + struct extent_buffer *leaf; + char *ptr; + int slot; + int len; + int total_len = 0; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * If the bottom subvolume does not exist directly under upper_limit, + * construct the path in from the bottom up. + */ + if (dirid != upper_limit) { + ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1]; + + root = btrfs_get_fs_root(fs_info, treeid, true); + if (IS_ERR(root)) + return PTR_ERR(root); + + key.objectid = dirid; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + while (1) { + struct btrfs_inode *temp_inode; + + ret = btrfs_search_backwards(root, &key, path); + if (ret < 0) + goto out_put; + else if (ret > 0) { + ret = -ENOENT; + goto out_put; + } + + leaf = path->nodes[0]; + slot = path->slots[0]; + + iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref); + len = btrfs_inode_ref_name_len(leaf, iref); + ptr -= len + 1; + total_len += len + 1; + if (ptr < args->path) { + ret = -ENAMETOOLONG; + goto out_put; + } + + *(ptr + len) = '/'; + read_extent_buffer(leaf, ptr, + (unsigned long)(iref + 1), len); + + /* + * We don't need the path anymore, so release it and + * avoid deadlocks and lockdep warnings in case + * btrfs_iget() needs to lookup the inode from its root + * btree and lock the same leaf. + */ + btrfs_release_path(path); + temp_inode = btrfs_iget(key.offset, root); + if (IS_ERR(temp_inode)) { + ret = PTR_ERR(temp_inode); + goto out_put; + } + /* Check the read+exec permission of this directory. */ + ret = inode_permission(idmap, &temp_inode->vfs_inode, + MAY_READ | MAY_EXEC); + iput(&temp_inode->vfs_inode); + if (ret) + goto out_put; + + if (key.offset == upper_limit) + break; + if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { + ret = -EACCES; + goto out_put; + } + + key.objectid = key.offset; + key.offset = (u64)-1; + dirid = key.objectid; + } + + memmove(args->path, ptr, total_len); + args->path[total_len] = '\0'; + btrfs_put_root(root); + root = NULL; + btrfs_release_path(path); + } + + /* Get the bottom subvolume's name from ROOT_REF */ + key.objectid = treeid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = args->treeid; + ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); + if (ret < 0) + return ret; + else if (ret > 0) + return -ENOENT; + + leaf = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(leaf, &key, slot); + + item_off = btrfs_item_ptr_offset(leaf, slot); + item_len = btrfs_item_size(leaf, slot); + /* Check if dirid in ROOT_REF corresponds to passed dirid */ + rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); + if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) + return -EINVAL; + + /* Copy subvolume's name */ + item_off += sizeof(struct btrfs_root_ref); + item_len -= sizeof(struct btrfs_root_ref); + read_extent_buffer(leaf, args->name, item_off, item_len); + args->name[item_len] = 0; + +out_put: + btrfs_put_root(root); + + return ret; +} + +static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root, + void __user *argp) +{ + bool new_root = false; + struct btrfs_ioctl_ino_lookup_args AUTO_KFREE(args); + int ret = 0; + + args = memdup_user(argp, sizeof(*args)); + if (IS_ERR(args)) + return PTR_ERR(args); + + /* + * Unprivileged query to obtain the containing subvolume root id. The + * path is reset so it's consistent with btrfs_search_path_in_tree. + */ + if (args->treeid == 0) + args->treeid = btrfs_root_id(root); + else + new_root = true; + + if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) { + args->name[0] = 0; + goto out; + } + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out; + } + + if (new_root) { + root = btrfs_get_fs_root(root->fs_info, args->treeid, true); + if (IS_ERR(root)) + return PTR_ERR(root); + } + ret = btrfs_search_path_in_tree(root, args->objectid, args->name); + if (new_root) + btrfs_put_root(root); + +out: + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + return -EFAULT; + + return ret; +} + +/* + * Version of ino_lookup ioctl (unprivileged) + * + * The main differences from ino_lookup ioctl are: + * + * 1. Read + Exec permission will be checked using inode_permission() during + * path construction. -EACCES will be returned in case of failure. + * 2. Path construction will be stopped at the inode number which corresponds + * to the fd with which this ioctl is called. If constructed path does not + * exist under fd's inode, -EACCES will be returned. + * 3. The name of bottom subvolume is also searched and filled. + */ +static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp) +{ + struct btrfs_ioctl_ino_lookup_user_args AUTO_KFREE(args); + struct inode *inode; + int ret; + + args = memdup_user(argp, sizeof(*args)); + if (IS_ERR(args)) + return PTR_ERR(args); + + inode = file_inode(file); + + if (args->dirid == BTRFS_FIRST_FREE_OBJECTID && + btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { + /* + * The subvolume does not exist under fd with which this is + * called + */ + return -EACCES; + } + + ret = btrfs_search_path_in_tree_user(file_mnt_idmap(file), inode, args); + + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + ret = -EFAULT; + + return ret; +} + +/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */ +static int _btrfs_ioctl_get_subvol_info(struct inode *inode, + struct btrfs_ioctl_get_subvol_info_args *subvol_info) +{ + struct btrfs_fs_info *fs_info; + struct btrfs_root *root; + struct btrfs_path *path; + struct btrfs_key key; + struct btrfs_root_item *root_item; + struct btrfs_root_ref *rref; + struct extent_buffer *leaf; + unsigned long item_off; + int slot; + int ret = 0; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + fs_info = BTRFS_I(inode)->root->fs_info; + + /* Get root_item of inode's subvolume */ + key.objectid = btrfs_root_id(BTRFS_I(inode)->root); + root = btrfs_get_fs_root(fs_info, key.objectid, true); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out_free; + } + root_item = &root->root_item; + + subvol_info->treeid = key.objectid; + + subvol_info->generation = btrfs_root_generation(root_item); + subvol_info->flags = btrfs_root_flags(root_item); + + memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE); + memcpy(subvol_info->parent_uuid, root_item->parent_uuid, + BTRFS_UUID_SIZE); + memcpy(subvol_info->received_uuid, root_item->received_uuid, + BTRFS_UUID_SIZE); + + subvol_info->ctransid = btrfs_root_ctransid(root_item); + subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime); + subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime); + + subvol_info->otransid = btrfs_root_otransid(root_item); + subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime); + subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime); + + subvol_info->stransid = btrfs_root_stransid(root_item); + subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime); + subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime); + + subvol_info->rtransid = btrfs_root_rtransid(root_item); + subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime); + subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime); + + if (key.objectid != BTRFS_FS_TREE_OBJECTID) { + /* Search root tree for ROOT_BACKREF of this subvolume */ + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = 0; + ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); + if (ret < 0) { + goto out; + } else if (path->slots[0] >= + btrfs_header_nritems(path->nodes[0])) { + ret = btrfs_next_leaf(fs_info->tree_root, path); + if (ret < 0) { + goto out; + } else if (unlikely(ret > 0)) { + ret = -EUCLEAN; + goto out; + } + } + + leaf = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(leaf, &key, slot); + if (key.objectid == subvol_info->treeid && + key.type == BTRFS_ROOT_BACKREF_KEY) { + u16 name_len; + + subvol_info->parent_id = key.offset; + + rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); + name_len = btrfs_root_ref_name_len(leaf, rref); + subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref); + + item_off = btrfs_item_ptr_offset(leaf, slot) + sizeof(*rref); + read_extent_buffer(leaf, subvol_info->name, + item_off, name_len); + } else { + ret = -ENOENT; + goto out; + } + ret = 0; + } + +out: + btrfs_put_root(root); +out_free: + btrfs_free_path(path); + return ret; +} + +#ifdef CONFIG_64BIT +static int btrfs_ioctl_get_subvol_info_32(struct inode *inode, void __user *argp) +{ + struct btrfs_ioctl_get_subvol_info_args AUTO_KFREE(subvol_info); + struct btrfs_ioctl_get_subvol_info_args_32 AUTO_KFREE(subvol_info_32); + int ret; + + subvol_info = kzalloc_obj(*subvol_info); + if (!subvol_info) + return -ENOMEM; + + subvol_info_32 = kzalloc_obj(*subvol_info_32); + if (!subvol_info_32) + return -ENOMEM; + + ret = _btrfs_ioctl_get_subvol_info(inode, subvol_info); + if (ret) + return ret; + + subvol_info_32->treeid = subvol_info->treeid; + memcpy(subvol_info_32->name, subvol_info->name, sizeof(subvol_info_32->name)); + subvol_info_32->parent_id = subvol_info->parent_id; + subvol_info_32->dirid = subvol_info->dirid; + subvol_info_32->generation = subvol_info->generation; + subvol_info_32->flags = subvol_info->flags; + memcpy(subvol_info_32->uuid, subvol_info->uuid, BTRFS_UUID_SIZE); + memcpy(subvol_info_32->parent_uuid, subvol_info->parent_uuid, BTRFS_UUID_SIZE); + memcpy(subvol_info_32->received_uuid, subvol_info->received_uuid, BTRFS_UUID_SIZE); + subvol_info_32->ctransid = subvol_info->ctransid; + subvol_info_32->otransid = subvol_info->otransid; + subvol_info_32->stransid = subvol_info->stransid; + subvol_info_32->rtransid = subvol_info->rtransid; + subvol_info_32->ctime.sec = subvol_info->ctime.sec; + subvol_info_32->ctime.nsec = subvol_info->ctime.nsec; + subvol_info_32->otime.sec = subvol_info->otime.sec; + subvol_info_32->otime.nsec = subvol_info->otime.nsec; + subvol_info_32->stime.sec = subvol_info->stime.sec; + subvol_info_32->stime.nsec = subvol_info->stime.nsec; + subvol_info_32->rtime.sec = subvol_info->rtime.sec; + subvol_info_32->rtime.nsec = subvol_info->rtime.nsec; + + if (copy_to_user(argp, subvol_info_32, sizeof(*subvol_info_32))) + ret = -EFAULT; + + return ret; +} +#endif + +static int btrfs_ioctl_get_subvol_info(struct inode *inode, void __user *argp) +{ + struct btrfs_ioctl_get_subvol_info_args AUTO_KFREE(subvol_info); + int ret; + + subvol_info = kzalloc_obj(*subvol_info); + if (!subvol_info) + return -ENOMEM; + + ret = _btrfs_ioctl_get_subvol_info(inode, subvol_info); + if (!ret && copy_to_user(argp, subvol_info, sizeof(*subvol_info))) + ret = -EFAULT; + + return ret; +} + +/* + * Return ROOT_REF information of the subvolume containing this inode + * except the subvolume name. + */ +static int btrfs_ioctl_get_subvol_rootref(struct btrfs_root *root, + void __user *argp) +{ + struct btrfs_ioctl_get_subvol_rootref_args AUTO_KFREE(rootrefs); + struct btrfs_root_ref *rref; + struct btrfs_path *path; + struct btrfs_key key; + struct extent_buffer *leaf; + u64 objectid; + int slot; + int ret; + u8 found; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + rootrefs = memdup_user(argp, sizeof(*rootrefs)); + if (IS_ERR(rootrefs)) { + btrfs_free_path(path); + return PTR_ERR(rootrefs); + } + + objectid = btrfs_root_id(root); + key.objectid = objectid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = rootrefs->min_treeid; + found = 0; + + root = root->fs_info->tree_root; + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + goto out; + } else if (path->slots[0] >= + btrfs_header_nritems(path->nodes[0])) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) { + goto out; + } else if (unlikely(ret > 0)) { + ret = -EUCLEAN; + goto out; + } + } + while (1) { + leaf = path->nodes[0]; + slot = path->slots[0]; + + btrfs_item_key_to_cpu(leaf, &key, slot); + if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) { + ret = 0; + goto out; + } + + if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) { + ret = -EOVERFLOW; + goto out; + } + + rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); + rootrefs->rootref[found].treeid = key.offset; + rootrefs->rootref[found].dirid = + btrfs_root_ref_dirid(leaf, rref); + found++; + + ret = btrfs_next_item(root, path); + if (ret < 0) { + goto out; + } else if (unlikely(ret > 0)) { + ret = -EUCLEAN; + goto out; + } + } + +out: + btrfs_free_path(path); + + if (!ret || ret == -EOVERFLOW) { + rootrefs->num_items = found; + /* update min_treeid for next search */ + if (found) + rootrefs->min_treeid = + rootrefs->rootref[found - 1].treeid + 1; + if (copy_to_user(argp, rootrefs, sizeof(*rootrefs))) + ret = -EFAULT; + } + + return ret; +} + +static noinline int btrfs_ioctl_snap_destroy(struct file *file, + void __user *arg, + bool destroy_v2) +{ + struct dentry *parent = file->f_path.dentry; + struct dentry *dentry; + struct inode *dir = d_inode(parent); + struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); + struct inode *inode; + struct btrfs_root *root = BTRFS_I(dir)->root; + struct btrfs_root *dest = NULL; + struct btrfs_ioctl_vol_args AUTO_KFREE(vol_args); + struct btrfs_ioctl_vol_args_v2 AUTO_KFREE(vol_args2); + struct mnt_idmap *idmap = file_mnt_idmap(file); + char *subvol_name, *subvol_name_ptr = NULL; + int ret = 0; + bool destroy_parent = false; + + /* We don't support snapshots with extent tree v2 yet. */ + if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { + btrfs_err(fs_info, + "extent tree v2 doesn't support snapshot deletion yet"); + return -EOPNOTSUPP; + } + + if (destroy_v2) { + vol_args2 = memdup_user(arg, sizeof(*vol_args2)); + if (IS_ERR(vol_args2)) + return PTR_ERR(vol_args2); + + if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) + return -EOPNOTSUPP; + + /* + * If SPEC_BY_ID is not set, we are looking for the subvolume by + * name, same as v1 currently does. + */ + if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) { + ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args2); + if (ret < 0) + return ret; + subvol_name = vol_args2->name; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + } else { + struct inode *old_dir; + + if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) + return -EINVAL; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + dentry = btrfs_get_dentry(fs_info->sb, + BTRFS_FIRST_FREE_OBJECTID, + vol_args2->subvolid, 0); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out_drop_write; + } + + /* + * Change the default parent since the subvolume being + * deleted can be outside of the current mount point. + */ + parent = btrfs_get_parent(dentry); + + /* + * At this point dentry->d_name can point to '/' if the + * subvolume we want to destroy is outsite of the + * current mount point, so we need to release the + * current dentry and execute the lookup to return a new + * one with ->d_name pointing to the + * <mount point>/subvol_name. + */ + dput(dentry); + if (IS_ERR(parent)) { + ret = PTR_ERR(parent); + goto out_drop_write; + } + old_dir = dir; + dir = d_inode(parent); + + /* + * If v2 was used with SPEC_BY_ID, a new parent was + * allocated since the subvolume can be outside of the + * current mount point. Later on we need to release this + * new parent dentry. + */ + destroy_parent = true; + + /* + * On idmapped mounts, deletion via subvolid is + * restricted to subvolumes that are immediate + * ancestors of the inode referenced by the file + * descriptor in the ioctl. Otherwise the idmapping + * could potentially be abused to delete subvolumes + * anywhere in the filesystem the user wouldn't be able + * to delete without an idmapped mount. + */ + if (old_dir != dir && idmap != &nop_mnt_idmap) { + ret = -EOPNOTSUPP; + goto free_parent; + } + + subvol_name_ptr = btrfs_get_subvol_name_from_objectid( + fs_info, vol_args2->subvolid); + if (IS_ERR(subvol_name_ptr)) { + ret = PTR_ERR(subvol_name_ptr); + goto free_parent; + } + /* subvol_name_ptr is already nul terminated */ + subvol_name = (char *)kbasename(subvol_name_ptr); + } + } else { + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + ret = btrfs_check_ioctl_vol_args_path(vol_args); + if (ret < 0) + return ret; + + subvol_name = vol_args->name; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + } + + if (strchr(subvol_name, '/') || + strcmp(subvol_name, "..") == 0) { + ret = -EINVAL; + goto free_subvol_name; + } + + if (!S_ISDIR(dir->i_mode)) { + ret = -ENOTDIR; + goto free_subvol_name; + } + + dentry = start_removing_killable(idmap, parent, &QSTR(subvol_name)); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out_end_removing; + } + + inode = d_inode(dentry); + dest = BTRFS_I(inode)->root; + if (!capable(CAP_SYS_ADMIN)) { + /* + * Regular user. Only allow this with a special mount + * option, when the user has write+exec access to the + * subvol root, and when rmdir(2) would have been + * allowed. + * + * Note that this is _not_ check that the subvol is + * empty or doesn't contain data that we wouldn't + * otherwise be able to delete. + * + * Users who want to delete empty subvols should try + * rmdir(2). + */ + ret = -EPERM; + if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED)) + goto out_end_removing; + + /* + * Do not allow deletion if the parent dir is the same + * as the dir to be deleted. That means the ioctl + * must be called on the dentry referencing the root + * of the subvol, not a random directory contained + * within it. + */ + ret = -EINVAL; + if (root == dest) + goto out_end_removing; + + ret = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC); + if (ret) + goto out_end_removing; + } + + /* check if subvolume may be deleted by a user */ + ret = may_delete_dentry(idmap, dir, dentry, true); + if (ret) + goto out_end_removing; + + if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { + ret = -EINVAL; + goto out_end_removing; + } + + btrfs_inode_lock(BTRFS_I(inode), 0); + ret = btrfs_delete_subvolume(BTRFS_I(dir), dentry); + btrfs_inode_unlock(BTRFS_I(inode), 0); + if (!ret) + d_delete_notify(dir, dentry); + +out_end_removing: + end_removing(dentry); +free_subvol_name: + kfree(subvol_name_ptr); +free_parent: + if (destroy_parent) + dput(parent); +out_drop_write: + mnt_drop_write_file(file); + return ret; +} + +static int btrfs_ioctl_defrag(struct file *file, void __user *argp) +{ + struct inode *inode = file_inode(file); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_ioctl_defrag_range_args range = {0}; + int ret; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (btrfs_root_readonly(root)) { + ret = -EROFS; + goto out; + } + + switch (inode->i_mode & S_IFMT) { + case S_IFDIR: + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out; + } + ret = btrfs_defrag_root(root); + break; + case S_IFREG: + /* + * Note that this does not check the file descriptor for write + * access. This prevents defragmenting executables that are + * running and allows defrag on files open in read-only mode. + */ + if (!capable(CAP_SYS_ADMIN) && + inode_permission(&nop_mnt_idmap, inode, MAY_WRITE)) { + ret = -EPERM; + goto out; + } + + /* + * Don't allow defrag on pre-content watched files, as it could + * populate the page cache with 0's via readahead. + */ + if (unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) { + ret = -EINVAL; + goto out; + } + + if (argp) { + if (copy_from_user(&range, argp, sizeof(range))) { + ret = -EFAULT; + goto out; + } + if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) { + ret = -EOPNOTSUPP; + goto out; + } + if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS) && + (range.flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS)) { + ret = -EINVAL; + goto out; + } + /* Compression or no-compression require to start the IO. */ + if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS) || + (range.flags & BTRFS_DEFRAG_RANGE_NOCOMPRESS)) { + range.flags |= BTRFS_DEFRAG_RANGE_START_IO; + range.extent_thresh = (u32)-1; + } + } else { + /* the rest are all set to zero by kzalloc */ + range.len = (u64)-1; + } + ret = btrfs_defrag_file(BTRFS_I(file_inode(file)), &file->f_ra, + &range, BTRFS_OLDEST_GENERATION, 0); + if (ret > 0) + ret = 0; + break; + default: + ret = -EINVAL; + } +out: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg) +{ + struct btrfs_ioctl_vol_args AUTO_KFREE(vol_args); + bool restore_op = false; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { + btrfs_err(fs_info, "device add not supported on extent tree v2 yet"); + return -EINVAL; + } + + if (fs_info->fs_devices->temp_fsid) { + btrfs_err(fs_info, + "device add not supported on cloned temp-fsid mount"); + return -EINVAL; + } + + if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) { + if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD)) + return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + + /* + * We can do the device add because we have a paused balanced, + * change the exclusive op type and remember we should bring + * back the paused balance + */ + fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD; + btrfs_exclop_start_unlock(fs_info); + restore_op = true; + } + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto out; + } + + ret = btrfs_check_ioctl_vol_args_path(vol_args); + if (ret < 0) + goto out; + + ret = btrfs_init_new_device(fs_info, vol_args->name); + + if (!ret) + btrfs_info(fs_info, "disk added %s", vol_args->name); + +out: + if (restore_op) + btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED); + else + btrfs_exclop_finish(fs_info); + return ret; +} + +static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg) +{ + BTRFS_DEV_LOOKUP_ARGS(args); + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_ioctl_vol_args_v2 AUTO_KFREE(vol_args); + struct file *bdev_file = NULL; + int ret; + bool cancel = false; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) { + ret = -EOPNOTSUPP; + goto out; + } + + ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args); + if (ret < 0) + goto out; + + if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) { + args.devid = vol_args->devid; + } else if (!strcmp("cancel", vol_args->name)) { + cancel = true; + } else { + ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name); + if (ret) + goto out; + } + + ret = mnt_want_write_file(file); + if (ret) + goto out; + + ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE, + cancel); + if (ret) + goto err_drop; + + /* Exclusive operation is now claimed */ + ret = btrfs_rm_device(fs_info, &args, &bdev_file); + + btrfs_exclop_finish(fs_info); + + if (!ret) { + if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) + btrfs_info(fs_info, "device deleted: id %llu", + vol_args->devid); + else + btrfs_info(fs_info, "device deleted: %s", + vol_args->name); + } +err_drop: + mnt_drop_write_file(file); + if (bdev_file) + btrfs_release_device_allow_freeze(bdev_file); +out: + btrfs_put_dev_args_from_path(&args); + return ret; +} + +static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) +{ + BTRFS_DEV_LOOKUP_ARGS(args); + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_ioctl_vol_args AUTO_KFREE(vol_args); + struct file *bdev_file = NULL; + int ret; + bool cancel = false; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + ret = btrfs_check_ioctl_vol_args_path(vol_args); + if (ret < 0) + return ret; + + if (!strcmp("cancel", vol_args->name)) { + cancel = true; + } else { + ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name); + if (ret) + goto out; + } + + ret = mnt_want_write_file(file); + if (ret) + goto out; + + ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE, + cancel); + if (ret == 0) { + ret = btrfs_rm_device(fs_info, &args, &bdev_file); + if (!ret) + btrfs_info(fs_info, "disk deleted %s", vol_args->name); + btrfs_exclop_finish(fs_info); + } + + mnt_drop_write_file(file); + if (bdev_file) + btrfs_release_device_allow_freeze(bdev_file); +out: + btrfs_put_dev_args_from_path(&args); + return ret; +} + +static long btrfs_ioctl_fs_info(const struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_fs_info_args AUTO_KFREE(fi_args); + struct btrfs_device *device; + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + u64 flags_in; + + fi_args = memdup_user(arg, sizeof(*fi_args)); + if (IS_ERR(fi_args)) + return PTR_ERR(fi_args); + + flags_in = fi_args->flags; + memset(fi_args, 0, sizeof(*fi_args)); + + rcu_read_lock(); + fi_args->num_devices = fs_devices->num_devices; + + list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { + if (device->devid > fi_args->max_id) + fi_args->max_id = device->devid; + } + rcu_read_unlock(); + + memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid)); + fi_args->nodesize = fs_info->nodesize; + fi_args->sectorsize = fs_info->sectorsize; + fi_args->clone_alignment = fs_info->sectorsize; + + if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) { + fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy); + fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy); + fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO; + } + + if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) { + fi_args->generation = btrfs_get_fs_generation(fs_info); + fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION; + } + + if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) { + memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid, + sizeof(fi_args->metadata_uuid)); + fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID; + } + + if (copy_to_user(arg, fi_args, sizeof(*fi_args))) + return -EFAULT; + + return 0; +} + +static long btrfs_ioctl_dev_info(const struct btrfs_fs_info *fs_info, + void __user *arg) +{ + BTRFS_DEV_LOOKUP_ARGS(args); + struct btrfs_ioctl_dev_info_args AUTO_KFREE(di_args); + struct btrfs_device *dev; + int ret = 0; + + di_args = memdup_user(arg, sizeof(*di_args)); + if (IS_ERR(di_args)) + return PTR_ERR(di_args); + + args.devid = di_args->devid; + if (!btrfs_is_empty_uuid(di_args->uuid)) + args.uuid = di_args->uuid; + + rcu_read_lock(); + dev = btrfs_find_device(fs_info->fs_devices, &args); + if (!dev) { + ret = -ENODEV; + goto out; + } + + di_args->devid = dev->devid; + di_args->bytes_used = btrfs_device_get_bytes_used(dev); + di_args->total_bytes = btrfs_device_get_total_bytes(dev); + memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); + memcpy(di_args->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE); + if (dev->name) + strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path)); + else + di_args->path[0] = '\0'; + +out: + rcu_read_unlock(); + if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) + ret = -EFAULT; + + return ret; +} + +static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_root *new_root; + struct btrfs_dir_item *di; + struct btrfs_trans_handle *trans; + struct btrfs_path *path = NULL; + struct btrfs_disk_key disk_key; + struct fscrypt_str name = FSTR_INIT("default", 7); + u64 objectid = 0; + u64 dir_id; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (copy_from_user(&objectid, argp, sizeof(objectid))) { + ret = -EFAULT; + goto out; + } + + if (!objectid) + objectid = BTRFS_FS_TREE_OBJECTID; + + new_root = btrfs_get_fs_root(fs_info, objectid, true); + if (IS_ERR(new_root)) { + ret = PTR_ERR(new_root); + goto out; + } + if (!btrfs_is_fstree(btrfs_root_id(new_root))) { + ret = -ENOENT; + goto out_free; + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out_free; + } + + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_free; + } + + dir_id = btrfs_super_root_dir(fs_info->super_copy); + di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path, + dir_id, &name, 1); + if (IS_ERR_OR_NULL(di)) { + btrfs_release_path(path); + btrfs_end_transaction(trans); + if (di) + ret = PTR_ERR(di); + else + ret = -ENOENT; + btrfs_err(fs_info, + "could not find default diritem for dir %llu: %pe", + dir_id, ERR_PTR(ret)); + goto out_free; + } + + btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); + btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); + btrfs_release_path(path); + + btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL); + btrfs_end_transaction(trans); +out_free: + btrfs_put_root(new_root); + btrfs_free_path(path); +out: + mnt_drop_write_file(file); + return ret; +} + +static void get_block_group_info(struct list_head *groups_list, + struct btrfs_ioctl_space_info *space) +{ + struct btrfs_block_group *block_group; + + space->total_bytes = 0; + space->used_bytes = 0; + space->flags = 0; + list_for_each_entry(block_group, groups_list, list) { + space->flags = block_group->flags; + space->total_bytes += block_group->length; + space->used_bytes += block_group->used; + } +} + +static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_space_args space_args = { 0 }; + struct btrfs_ioctl_space_info space; + struct btrfs_ioctl_space_info *dest; + struct btrfs_ioctl_space_info AUTO_KFREE(dest_orig); + struct btrfs_ioctl_space_info __user *user_dest; + struct btrfs_space_info *info; + static const u64 types[] = { + BTRFS_BLOCK_GROUP_DATA, + BTRFS_BLOCK_GROUP_SYSTEM, + BTRFS_BLOCK_GROUP_METADATA, + BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA + }; + int num_types = 4; + int alloc_size; + int ret = 0; + u64 slot_count = 0; + int i, c; + + if (copy_from_user(&space_args, + (struct btrfs_ioctl_space_args __user *)arg, + sizeof(space_args))) + return -EFAULT; + + for (i = 0; i < num_types; i++) { + struct btrfs_space_info *tmp; + + info = NULL; + list_for_each_entry(tmp, &fs_info->space_info, list) { + if (tmp->flags == types[i]) { + info = tmp; + break; + } + } + + if (!info) + continue; + + down_read(&info->groups_sem); + for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { + if (!list_empty(&info->block_groups[c])) + slot_count++; + } + up_read(&info->groups_sem); + } + + /* + * Global block reserve, exported as a space_info + */ + slot_count++; + + /* space_slots == 0 means they are asking for a count */ + if (space_args.space_slots == 0) { + space_args.total_spaces = slot_count; + goto out; + } + + slot_count = min_t(u64, space_args.space_slots, slot_count); + + alloc_size = sizeof(*dest) * slot_count; + + /* we generally have at most 6 or so space infos, one for each raid + * level. So, a whole page should be more than enough for everyone + */ + if (alloc_size > PAGE_SIZE) + return -ENOMEM; + + space_args.total_spaces = 0; + dest = kzalloc(alloc_size, GFP_KERNEL); + if (!dest) + return -ENOMEM; + dest_orig = dest; + + /* now we have a buffer to copy into */ + for (i = 0; i < num_types; i++) { + struct btrfs_space_info *tmp; + + if (!slot_count) + break; + + info = NULL; + list_for_each_entry(tmp, &fs_info->space_info, list) { + if (tmp->flags == types[i]) { + info = tmp; + break; + } + } + + if (!info) + continue; + down_read(&info->groups_sem); + for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { + if (!list_empty(&info->block_groups[c])) { + get_block_group_info(&info->block_groups[c], + &space); + memcpy(dest, &space, sizeof(space)); + dest++; + space_args.total_spaces++; + slot_count--; + } + if (!slot_count) + break; + } + up_read(&info->groups_sem); + } + + /* + * Add global block reserve + */ + if (slot_count) { + struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; + + spin_lock(&block_rsv->lock); + space.total_bytes = block_rsv->size; + space.used_bytes = block_rsv->size - block_rsv->reserved; + spin_unlock(&block_rsv->lock); + space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; + memcpy(dest, &space, sizeof(space)); + space_args.total_spaces++; + } + + user_dest = (struct btrfs_ioctl_space_info __user *) + (arg + sizeof(struct btrfs_ioctl_space_args)); + + if (copy_to_user(user_dest, dest_orig, + space_args.total_spaces * sizeof(*dest_orig))) + return -EFAULT; + +out: + if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args))) + ret = -EFAULT; + + return ret; +} + +static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root, + void __user *argp) +{ + struct btrfs_trans_handle *trans; + u64 transid; + + /* + * Start orphan cleanup here for the given root in case it hasn't been + * started already by other means. Errors are handled in the other + * functions during transaction commit. + */ + btrfs_orphan_cleanup(root); + + trans = btrfs_attach_transaction_barrier(root); + if (IS_ERR(trans)) { + if (PTR_ERR(trans) != -ENOENT) + return PTR_ERR(trans); + + /* No running transaction, don't bother */ + transid = btrfs_get_last_trans_committed(root->fs_info); + goto out; + } + transid = trans->transid; + btrfs_commit_transaction_async(trans); +out: + if (argp) + if (copy_to_user(argp, &transid, sizeof(transid))) + return -EFAULT; + return 0; +} + +static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info, + void __user *argp) +{ + /* By default wait for the current transaction. */ + u64 transid = 0; + + if (argp) + if (copy_from_user(&transid, argp, sizeof(transid))) + return -EFAULT; + + return btrfs_wait_for_commit(fs_info, transid); +} + +static long btrfs_ioctl_scrub(struct file *file, void __user *arg) +{ + struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file)); + struct btrfs_ioctl_scrub_args AUTO_KFREE(sa); + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { + btrfs_err(fs_info, "scrub: extent tree v2 not yet supported"); + return -EINVAL; + } + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + if (sa->flags & ~BTRFS_SCRUB_SUPPORTED_FLAGS) + return -EOPNOTSUPP; + + if (!(sa->flags & BTRFS_SCRUB_READONLY)) { + ret = mnt_want_write_file(file); + if (ret) + return ret; + } + + ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end, + &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, + false); + + /* + * Copy scrub args to user space even if btrfs_scrub_dev() returned an + * error. This is important as it allows user space to know how much + * progress scrub has done. For example, if scrub is canceled we get + * -ECANCELED from btrfs_scrub_dev() and return that error back to user + * space. Later user space can inspect the progress from the structure + * btrfs_ioctl_scrub_args and resume scrub from where it left off + * previously (btrfs-progs does this). + * If we fail to copy the btrfs_ioctl_scrub_args structure to user space + * then return -EFAULT to signal the structure was not copied or it may + * be corrupt and unreliable due to a partial copy. + */ + if (copy_to_user(arg, sa, sizeof(*sa))) + ret = -EFAULT; + + if (!(sa->flags & BTRFS_SCRUB_READONLY)) + mnt_drop_write_file(file); + + return ret; +} + +static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info) +{ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + return btrfs_scrub_cancel(fs_info); +} + +static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_scrub_args AUTO_KFREE(sa); + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress); + + if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa))) + return -EFAULT; + + return ret; +} + +static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_get_dev_stats AUTO_KFREE(sa); + int ret; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = btrfs_get_dev_stats(fs_info, sa); + + if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa))) + return -EFAULT; + + return ret; +} + +static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_dev_replace_args AUTO_KFREE(p); + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { + btrfs_err(fs_info, "device replace not supported on extent tree v2 yet"); + return -EINVAL; + } + + p = memdup_user(arg, sizeof(*p)); + if (IS_ERR(p)) + return PTR_ERR(p); + + switch (p->cmd) { + case BTRFS_IOCTL_DEV_REPLACE_CMD_START: + if (sb_rdonly(fs_info->sb)) + return -EROFS; + if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) { + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + } else { + ret = btrfs_dev_replace_by_ioctl(fs_info, p); + btrfs_exclop_finish(fs_info); + } + break; + case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: + btrfs_dev_replace_status(fs_info, p); + ret = 0; + break; + case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: + p->result = btrfs_dev_replace_cancel(fs_info); + ret = 0; + break; + default: + ret = -EINVAL; + break; + } + + if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p))) + return -EFAULT; + + return ret; +} + +static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg) +{ + int ret = 0; + int i; + u64 rel_ptr; + int size; + struct btrfs_ioctl_ino_path_args AUTO_KFREE(ipa); + struct inode_fs_paths *ipath __free(inode_fs_paths) = NULL; + struct btrfs_path *path; + + if (!capable(CAP_DAC_READ_SEARCH)) + return -EPERM; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + ipa = memdup_user(arg, sizeof(*ipa)); + if (IS_ERR(ipa)) { + ret = PTR_ERR(ipa); + ipa = NULL; + goto out; + } + + size = min_t(u32, ipa->size, 4096); + ipath = init_ipath(size, root, path); + if (IS_ERR(ipath)) { + ret = PTR_ERR(ipath); + ipath = NULL; + goto out; + } + + ret = paths_from_inode(ipa->inum, ipath); + if (ret < 0) + goto out; + + for (i = 0; i < ipath->fspath->elem_cnt; ++i) { + rel_ptr = ipath->fspath->val[i] - + (u64)(unsigned long)ipath->fspath->val; + ipath->fspath->val[i] = rel_ptr; + } + + btrfs_free_path(path); + path = NULL; + ret = copy_to_user((void __user *)(unsigned long)ipa->fspath, + ipath->fspath, size); + if (ret) { + ret = -EFAULT; + goto out; + } + +out: + btrfs_free_path(path); + + return ret; +} + +static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, + void __user *arg, int version) +{ + int ret = 0; + int size; + struct btrfs_ioctl_logical_ino_args AUTO_KFREE(loi); + struct btrfs_data_container AUTO_KVFREE(inodes); + bool ignore_offset; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + loi = memdup_user(arg, sizeof(*loi)); + if (IS_ERR(loi)) + return PTR_ERR(loi); + + if (version == 1) { + ignore_offset = false; + size = min_t(u32, loi->size, SZ_64K); + } else { + /* All reserved bits must be 0 for now */ + if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) + return -EINVAL; + + /* Only accept flags we have defined so far */ + if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) + return -EINVAL; + + ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET; + size = min_t(u32, loi->size, SZ_16M); + } + + inodes = init_data_container(size); + if (IS_ERR(inodes)) + return PTR_ERR(inodes); + + ret = iterate_inodes_from_logical(loi->logical, fs_info, inodes, ignore_offset); + if (ret == -EINVAL) + return -ENOENT; + if (ret < 0) + return ret; + + ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes, + size); + if (ret) + ret = -EFAULT; + + return ret; +} + +void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_balance_args *bargs) +{ + struct btrfs_balance_control *bctl = fs_info->balance_ctl; + + bargs->flags = bctl->flags; + + if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) + bargs->state |= BTRFS_BALANCE_STATE_RUNNING; + if (atomic_read(&fs_info->balance_pause_req)) + bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ; + if (atomic_read(&fs_info->balance_cancel_req)) + bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ; + + memcpy(&bargs->data, &bctl->data, sizeof(bargs->data)); + memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta)); + memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys)); + + spin_lock(&fs_info->balance_lock); + memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat)); + spin_unlock(&fs_info->balance_lock); +} + +/* + * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as + * required. + * + * @fs_info: the filesystem + * @excl_acquired: ptr to boolean value which is set to false in case balance + * is being resumed + * + * Return 0 on success in which case both fs_info::balance is acquired as well + * as exclusive ops are blocked. In case of failure return an error code. + */ +static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired) +{ + int ret; + + /* + * Exclusive operation is locked. Three possibilities: + * (1) some other op is running + * (2) balance is running + * (3) balance is paused -- special case (think resume) + */ + while (1) { + if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) { + *excl_acquired = true; + mutex_lock(&fs_info->balance_mutex); + return 0; + } + + mutex_lock(&fs_info->balance_mutex); + if (fs_info->balance_ctl) { + /* This is either (2) or (3) */ + if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { + /* This is (2) */ + ret = -EINPROGRESS; + goto out_failure; + + } else { + mutex_unlock(&fs_info->balance_mutex); + /* + * Lock released to allow other waiters to + * continue, we'll reexamine the status again. + */ + mutex_lock(&fs_info->balance_mutex); + + if (fs_info->balance_ctl && + !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { + /* This is (3) */ + *excl_acquired = false; + return 0; + } + } + } else { + /* This is (1) */ + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + goto out_failure; + } + + mutex_unlock(&fs_info->balance_mutex); + } + +out_failure: + mutex_unlock(&fs_info->balance_mutex); + *excl_acquired = false; + return ret; +} + +static long btrfs_ioctl_balance(struct file *file, void __user *arg) +{ + struct btrfs_root *root = BTRFS_I(file_inode(file))->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_ioctl_balance_args AUTO_KFREE(bargs); + struct btrfs_balance_control *bctl; + bool need_unlock = true; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + bargs = memdup_user(arg, sizeof(*bargs)); + if (IS_ERR(bargs)) { + ret = PTR_ERR(bargs); + bargs = NULL; + goto out; + } + + ret = btrfs_try_lock_balance(fs_info, &need_unlock); + if (ret) + goto out; + + lockdep_assert_held(&fs_info->balance_mutex); + + if (bargs->flags & BTRFS_BALANCE_RESUME) { + if (!fs_info->balance_ctl) { + ret = -ENOTCONN; + goto out_unlock; + } + + bctl = fs_info->balance_ctl; + spin_lock(&fs_info->balance_lock); + bctl->flags |= BTRFS_BALANCE_RESUME; + spin_unlock(&fs_info->balance_lock); + btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE); + + goto do_balance; + } + + if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) { + ret = -EINVAL; + goto out_unlock; + } + + if (fs_info->balance_ctl) { + ret = -EINPROGRESS; + goto out_unlock; + } + + bctl = kzalloc_obj(*bctl); + if (!bctl) { + ret = -ENOMEM; + goto out_unlock; + } + + memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); + memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); + memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); + + bctl->flags = bargs->flags; +do_balance: + /* + * Ownership of bctl and exclusive operation goes to btrfs_balance. + * bctl is freed in reset_balance_state, or, if restriper was paused + * all the way until unmount, in free_fs_info. The flag should be + * cleared after reset_balance_state. + */ + need_unlock = false; + + ret = btrfs_balance(fs_info, bctl, bargs); + bctl = NULL; + + if (ret == 0 || ret == -ECANCELED) { + if (copy_to_user(arg, bargs, sizeof(*bargs))) + ret = -EFAULT; + } + + kfree(bctl); +out_unlock: + mutex_unlock(&fs_info->balance_mutex); + if (need_unlock) + btrfs_exclop_finish(fs_info); +out: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd) +{ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + switch (cmd) { + case BTRFS_BALANCE_CTL_PAUSE: + return btrfs_pause_balance(fs_info); + case BTRFS_BALANCE_CTL_CANCEL: + return btrfs_cancel_balance(fs_info); + } + + return -EINVAL; +} + +static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_balance_args AUTO_KFREE(bargs); + int ret = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + mutex_lock(&fs_info->balance_mutex); + if (!fs_info->balance_ctl) { + ret = -ENOTCONN; + goto out; + } + + bargs = kzalloc(sizeof(*bargs), GFP_KERNEL); + if (!bargs) { + ret = -ENOMEM; + goto out; + } + + btrfs_update_ioctl_balance_args(fs_info, bargs); + + if (copy_to_user(arg, bargs, sizeof(*bargs))) + ret = -EFAULT; +out: + mutex_unlock(&fs_info->balance_mutex); + return ret; +} + +static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_ioctl_quota_ctl_args AUTO_KFREE(sa); + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) { + ret = PTR_ERR(sa); + goto drop_write; + } + + switch (sa->cmd) { + case BTRFS_QUOTA_CTL_ENABLE: + case BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA: + down_write(&fs_info->subvol_sem); + ret = btrfs_quota_enable(fs_info, sa); + up_write(&fs_info->subvol_sem); + break; + case BTRFS_QUOTA_CTL_DISABLE: + /* + * Lock the cleaner mutex to prevent races with concurrent + * relocation, because relocation may be building backrefs for + * blocks of the quota root while we are deleting the root. This + * is like dropping fs roots of deleted snapshots/subvolumes, we + * need the same protection. + * + * This also prevents races between concurrent tasks trying to + * disable quotas, because we will unlock and relock + * qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes. + * + * We take this here because we have the dependency of + * + * inode_lock -> subvol_sem + * + * because of rename. With relocation we can prealloc extents, + * so that makes the dependency chain + * + * cleaner_mutex -> inode_lock -> subvol_sem + * + * so we must take the cleaner_mutex here before we take the + * subvol_sem. The deadlock can't actually happen, but this + * quiets lockdep. + */ + mutex_lock(&fs_info->cleaner_mutex); + down_write(&fs_info->subvol_sem); + ret = btrfs_quota_disable(fs_info); + up_write(&fs_info->subvol_sem); + mutex_unlock(&fs_info->cleaner_mutex); + break; + default: + ret = -EINVAL; + break; + } + +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *quota_root; + struct btrfs_ioctl_qgroup_assign_args AUTO_KFREE(sa); + struct btrfs_qgroup_list AUTO_KFREE(prealloc); + struct btrfs_trans_handle *trans; + int ret; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!btrfs_qgroup_enabled(fs_info)) + return -ENOTCONN; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) { + ret = PTR_ERR(sa); + goto drop_write; + } + + if (sa->assign) { + prealloc = kzalloc_obj(*prealloc); + if (!prealloc) { + ret = -ENOMEM; + goto drop_write; + } + } + + mutex_lock(&fs_info->qgroup_ioctl_lock); + quota_root = btrfs_grab_root(fs_info->quota_root); + mutex_unlock(&fs_info->qgroup_ioctl_lock); + + if (!quota_root) { + ret = -ENOTCONN; + goto drop_write; + } + + /* 2 BTRFS_QGROUP_RELATION_KEY items. */ + trans = btrfs_start_transaction(quota_root, 2); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + btrfs_put_root(quota_root); + goto drop_write; + } + + /* + * Prealloc ownership is moved to the relation handler, there it's used + * or freed on error. + */ + if (sa->assign) { + ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst, prealloc); + prealloc = NULL; + } else { + ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst); + } + + /* update qgroup status and info */ + mutex_lock(&fs_info->qgroup_ioctl_lock); + err = btrfs_run_qgroups(trans); + mutex_unlock(&fs_info->qgroup_ioctl_lock); + if (err < 0) + btrfs_warn(fs_info, + "qgroup status update failed after %s relation, marked as inconsistent", + sa->assign ? "adding" : "deleting"); + err = btrfs_end_transaction(trans); + btrfs_put_root(quota_root); + if (err && !ret) + ret = err; + +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *quota_root; + struct btrfs_ioctl_qgroup_create_args AUTO_KFREE(sa); + struct btrfs_trans_handle *trans; + int ret; + int err; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!btrfs_qgroup_enabled(fs_info)) + return -ENOTCONN; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) { + ret = PTR_ERR(sa); + goto drop_write; + } + + if (!sa->qgroupid) { + ret = -EINVAL; + goto drop_write; + } + + if (sa->create && btrfs_is_fstree(sa->qgroupid)) { + ret = -EINVAL; + goto drop_write; + } + + mutex_lock(&fs_info->qgroup_ioctl_lock); + quota_root = btrfs_grab_root(fs_info->quota_root); + mutex_unlock(&fs_info->qgroup_ioctl_lock); + + if (!quota_root) { + ret = -ENOTCONN; + goto drop_write; + } + + /* + * 1 BTRFS_QGROUP_INFO_KEY item. + * 1 BTRFS_QGROUP_LIMIT_KEY item. + */ + trans = btrfs_start_transaction(quota_root, 2); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + btrfs_put_root(quota_root); + goto drop_write; + } + + if (sa->create) { + ret = btrfs_create_qgroup(trans, sa->qgroupid); + } else { + ret = btrfs_remove_qgroup(trans, sa->qgroupid); + } + + err = btrfs_end_transaction(trans); + btrfs_put_root(quota_root); + if (err && !ret) + ret = err; + +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_root *quota_root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_ioctl_qgroup_limit_args AUTO_KFREE(sa); + struct btrfs_trans_handle *trans; + int ret; + int err; + u64 qgroupid; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!btrfs_qgroup_enabled(fs_info)) + return -ENOTCONN; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) { + ret = PTR_ERR(sa); + goto drop_write; + } + + mutex_lock(&fs_info->qgroup_ioctl_lock); + quota_root = btrfs_grab_root(fs_info->quota_root); + mutex_unlock(&fs_info->qgroup_ioctl_lock); + + if (!quota_root) { + ret = -ENOTCONN; + goto drop_write; + } + + /* 1 BTRFS_QGROUP_LIMIT_KEY item. */ + trans = btrfs_start_transaction(quota_root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + btrfs_put_root(quota_root); + goto drop_write; + } + + qgroupid = sa->qgroupid; + if (!qgroupid) { + /* take the current subvol as qgroup */ + qgroupid = btrfs_root_id(root); + } + + ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim); + + err = btrfs_end_transaction(trans); + btrfs_put_root(quota_root); + if (err && !ret) + ret = err; + +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_ioctl_quota_rescan_args AUTO_KFREE(qsa); + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (!btrfs_qgroup_enabled(fs_info)) + return -ENOTCONN; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + qsa = memdup_user(arg, sizeof(*qsa)); + if (IS_ERR(qsa)) { + ret = PTR_ERR(qsa); + goto drop_write; + } + + if (qsa->flags) { + ret = -EINVAL; + goto drop_write; + } + + ret = btrfs_qgroup_rescan(fs_info); + +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_quota_rescan_args qsa = {0}; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { + qsa.flags = 1; + qsa.progress = fs_info->qgroup_rescan_progress.objectid; + } + + if (copy_to_user(arg, &qsa, sizeof(qsa))) + return -EFAULT; + + return 0; +} + +static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info) +{ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + return btrfs_qgroup_wait_for_completion(fs_info, true); +} + +static long _btrfs_ioctl_set_received_subvol(struct file *file, + struct mnt_idmap *idmap, + struct btrfs_ioctl_received_subvol_args *sa) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_root_item *root_item = &root->root_item; + struct btrfs_trans_handle *trans; + struct timespec64 ct = current_time(inode); + int ret = 0; + int received_uuid_changed; + + if (!inode_owner_or_capable(idmap, inode)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret < 0) + return ret; + + down_write(&fs_info->subvol_sem); + + if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { + ret = -EINVAL; + goto out; + } + + if (btrfs_root_readonly(root)) { + ret = -EROFS; + goto out; + } + + received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, + BTRFS_UUID_SIZE); + + /* + * Before we attempt to add the new received uuid, check if we have room + * for it in case there's already an item. If the size of the existing + * item plus this root's ID (u64) exceeds the maximum item size, we can + * return here without the need to abort a transaction. If we don't do + * this check, the btrfs_uuid_tree_add() call below would fail with + * -EOVERFLOW and result in a transaction abort. Malicious users could + * exploit this to turn the fs into RO mode. + */ + if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { + ret = btrfs_uuid_tree_check_overflow(fs_info, sa->uuid, + BTRFS_UUID_KEY_RECEIVED_SUBVOL); + if (ret < 0) + goto out; + } + + /* + * 1 - root item + * 2 - uuid items (received uuid + subvol uuid) + */ + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + trans = NULL; + goto out; + } + + sa->rtransid = trans->transid; + sa->rtime.sec = ct.tv_sec; + sa->rtime.nsec = ct.tv_nsec; + + if (received_uuid_changed && + !btrfs_is_empty_uuid(root_item->received_uuid)) { + ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid, + BTRFS_UUID_KEY_RECEIVED_SUBVOL, + btrfs_root_id(root)); + if (unlikely(ret && ret != -ENOENT)) { + btrfs_end_transaction(trans); + goto out; + } + } + memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE); + btrfs_set_root_stransid(root_item, sa->stransid); + btrfs_set_root_rtransid(root_item, sa->rtransid); + btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec); + btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec); + btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec); + btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec); + + ret = btrfs_update_root(trans, fs_info->tree_root, + &root->root_key, &root->root_item); + if (unlikely(ret < 0)) { + btrfs_abort_transaction(trans, ret); + btrfs_end_transaction(trans); + goto out; + } + if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) { + ret = btrfs_uuid_tree_add(trans, sa->uuid, + BTRFS_UUID_KEY_RECEIVED_SUBVOL, + btrfs_root_id(root)); + if (unlikely(ret < 0)) { + btrfs_abort_transaction(trans, ret); + btrfs_end_transaction(trans); + goto out; + } + } + ret = btrfs_commit_transaction(trans); +out: + up_write(&fs_info->subvol_sem); + mnt_drop_write_file(file); + return ret; +} + +#ifdef CONFIG_64BIT +static long btrfs_ioctl_set_received_subvol_32(struct file *file, + void __user *arg) +{ + struct btrfs_ioctl_received_subvol_args_32 AUTO_KFREE(args32); + struct btrfs_ioctl_received_subvol_args AUTO_KFREE(args64); + int ret = 0; + + args32 = memdup_user(arg, sizeof(*args32)); + if (IS_ERR(args32)) + return PTR_ERR(args32); + + args64 = kmalloc_obj(*args64); + if (!args64) + return -ENOMEM; + + memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE); + args64->stransid = args32->stransid; + args64->rtransid = args32->rtransid; + args64->stime.sec = args32->stime.sec; + args64->stime.nsec = args32->stime.nsec; + args64->rtime.sec = args32->rtime.sec; + args64->rtime.nsec = args32->rtime.nsec; + args64->flags = args32->flags; + + ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), args64); + if (ret) + return ret; + + memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE); + args32->stransid = args64->stransid; + args32->rtransid = args64->rtransid; + args32->stime.sec = args64->stime.sec; + args32->stime.nsec = args64->stime.nsec; + args32->rtime.sec = args64->rtime.sec; + args32->rtime.nsec = args64->rtime.nsec; + args32->flags = args64->flags; + + ret = copy_to_user(arg, args32, sizeof(*args32)); + if (ret) + return -EFAULT; + + return 0; +} +#endif + +static long btrfs_ioctl_set_received_subvol(struct file *file, + void __user *arg) +{ + struct btrfs_ioctl_received_subvol_args AUTO_KFREE(sa); + int ret = 0; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), sa); + if (ret) + return ret; + + ret = copy_to_user(arg, sa, sizeof(*sa)); + if (ret) + return -EFAULT; + + return 0; +} + +static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + size_t len; + int ret; + char label[BTRFS_LABEL_SIZE]; + + spin_lock(&fs_info->super_lock); + memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE); + spin_unlock(&fs_info->super_lock); + + len = strnlen(label, BTRFS_LABEL_SIZE); + + if (len == BTRFS_LABEL_SIZE) { + btrfs_warn(fs_info, + "label is too long, return the first %zu bytes", + --len); + } + + ret = copy_to_user(arg, label, len); + + return ret ? -EFAULT : 0; +} + +static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_super_block *super_block = fs_info->super_copy; + struct btrfs_trans_handle *trans; + char label[BTRFS_LABEL_SIZE]; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (copy_from_user(label, arg, sizeof(label))) + return -EFAULT; + + if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { + btrfs_err(fs_info, + "unable to set label with more than %d bytes", + BTRFS_LABEL_SIZE - 1); + return -EINVAL; + } + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_unlock; + } + + spin_lock(&fs_info->super_lock); + strscpy(super_block->label, label); + spin_unlock(&fs_info->super_lock); + ret = btrfs_commit_transaction(trans); + +out_unlock: + mnt_drop_write_file(file); + return ret; +} + +#define INIT_FEATURE_FLAGS(suffix) \ + { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \ + .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \ + .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix } + +int btrfs_ioctl_get_supported_features(void __user *arg) +{ + static const struct btrfs_ioctl_feature_flags features[3] = { + INIT_FEATURE_FLAGS(SUPP), + INIT_FEATURE_FLAGS(SAFE_SET), + INIT_FEATURE_FLAGS(SAFE_CLEAR) + }; + + if (copy_to_user(arg, &features, sizeof(features))) + return -EFAULT; + + return 0; +} + +static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_super_block *super_block = fs_info->super_copy; + struct btrfs_ioctl_feature_flags features; + + features.compat_flags = btrfs_super_compat_flags(super_block); + features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); + features.incompat_flags = btrfs_super_incompat_flags(super_block); + + if (copy_to_user(arg, &features, sizeof(features))) + return -EFAULT; + + return 0; +} + +static int check_feature_bits(const struct btrfs_fs_info *fs_info, + enum btrfs_feature_set set, + u64 change_mask, u64 flags, u64 supported_flags, + u64 safe_set, u64 safe_clear) +{ + const char *type = btrfs_feature_set_name(set); + const char AUTO_KFREE(names); + u64 disallowed, unsupported; + u64 set_mask = flags & change_mask; + u64 clear_mask = ~flags & change_mask; + + unsupported = set_mask & ~supported_flags; + if (unsupported) { + names = btrfs_printable_features(set, unsupported); + if (names) + btrfs_warn(fs_info, + "this kernel does not support the %s feature bit%s", + names, strchr(names, ',') ? "s" : ""); + else + btrfs_warn(fs_info, + "this kernel does not support %s bits 0x%llx", + type, unsupported); + return -EOPNOTSUPP; + } + + disallowed = set_mask & ~safe_set; + if (disallowed) { + names = btrfs_printable_features(set, disallowed); + if (names) + btrfs_warn(fs_info, + "can't set the %s feature bit%s while mounted", + names, strchr(names, ',') ? "s" : ""); + else + btrfs_warn(fs_info, + "can't set %s bits 0x%llx while mounted", + type, disallowed); + return -EPERM; + } + + disallowed = clear_mask & ~safe_clear; + if (disallowed) { + names = btrfs_printable_features(set, disallowed); + if (names) + btrfs_warn(fs_info, + "can't clear the %s feature bit%s while mounted", + names, strchr(names, ',') ? "s" : ""); + else + btrfs_warn(fs_info, + "can't clear %s bits 0x%llx while mounted", + type, disallowed); + return -EPERM; + } + + return 0; +} + +#define check_feature(fs_info, change_mask, flags, mask_base) \ +check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \ + BTRFS_FEATURE_ ## mask_base ## _SUPP, \ + BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \ + BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR) + +static int btrfs_ioctl_set_features(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_super_block *super_block = fs_info->super_copy; + struct btrfs_ioctl_feature_flags flags[2]; + struct btrfs_trans_handle *trans; + u64 newflags; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (copy_from_user(flags, arg, sizeof(flags))) + return -EFAULT; + + /* Nothing to do */ + if (!flags[0].compat_flags && !flags[0].compat_ro_flags && + !flags[0].incompat_flags) + return 0; + + ret = check_feature(fs_info, flags[0].compat_flags, + flags[1].compat_flags, COMPAT); + if (ret) + return ret; + + ret = check_feature(fs_info, flags[0].compat_ro_flags, + flags[1].compat_ro_flags, COMPAT_RO); + if (ret) + return ret; + + ret = check_feature(fs_info, flags[0].incompat_flags, + flags[1].incompat_flags, INCOMPAT); + if (ret) + return ret; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_drop_write; + } + + spin_lock(&fs_info->super_lock); + newflags = btrfs_super_compat_flags(super_block); + newflags |= flags[0].compat_flags & flags[1].compat_flags; + newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); + btrfs_set_super_compat_flags(super_block, newflags); + + newflags = btrfs_super_compat_ro_flags(super_block); + newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; + newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); + btrfs_set_super_compat_ro_flags(super_block, newflags); + + newflags = btrfs_super_incompat_flags(super_block); + newflags |= flags[0].incompat_flags & flags[1].incompat_flags; + newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); + btrfs_set_super_incompat_flags(super_block, newflags); + spin_unlock(&fs_info->super_lock); + + ret = btrfs_commit_transaction(trans); +out_drop_write: + mnt_drop_write_file(file); + + return ret; +} + +static int _btrfs_ioctl_send(struct btrfs_root *root, void __user *argp, bool compat) +{ + struct btrfs_ioctl_send_args AUTO_KFREE(arg); + + if (compat) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + int ret; + struct btrfs_ioctl_send_args_32 args32 = { 0 }; + + ret = copy_from_user(&args32, argp, sizeof(args32)); + if (ret) + return -EFAULT; + arg = kzalloc_obj(*arg); + if (!arg) + return -ENOMEM; + arg->send_fd = args32.send_fd; + arg->clone_sources_count = args32.clone_sources_count; + arg->clone_sources = compat_ptr(args32.clone_sources); + arg->parent_root = args32.parent_root; + arg->flags = args32.flags; + arg->version = args32.version; + memcpy(arg->reserved, args32.reserved, + sizeof(args32.reserved)); +#else + return -ENOTTY; +#endif + } else { + arg = memdup_user(argp, sizeof(*arg)); + if (IS_ERR(arg)) + return PTR_ERR(arg); + } + return btrfs_ioctl_send(root, arg); +} + +static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp, + bool compat) +{ + struct btrfs_ioctl_encoded_io_args args = { 0 }; + size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args, + flags); + size_t copy_end; + struct btrfs_inode *inode = BTRFS_I(file_inode(file)); + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct extent_io_tree *io_tree = &inode->io_tree; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + struct iov_iter iter; + loff_t pos; + struct kiocb kiocb; + ssize_t ret; + u64 disk_bytenr, disk_io_size; + struct extent_state *cached_state = NULL; + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out_acct; + } + + if (compat) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_encoded_io_args_32 args32; + + copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32, + flags); + if (copy_from_user(&args32, argp, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + args.iov = compat_ptr(args32.iov); + args.iovcnt = args32.iovcnt; + args.offset = args32.offset; + args.flags = args32.flags; +#else + return -ENOTTY; +#endif + } else { + copy_end = copy_end_kernel; + if (copy_from_user(&args, argp, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + } + if (args.flags != 0) { + ret = -EINVAL; + goto out_acct; + } + + ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack), + &iov, &iter); + if (ret < 0) + goto out_acct; + + if (iov_iter_count(&iter) == 0) { + ret = 0; + goto out_iov; + } + pos = args.offset; + ret = rw_verify_area(READ, file, &pos, args.len); + if (ret < 0) + goto out_iov; + + init_sync_kiocb(&kiocb, file); + kiocb.ki_pos = pos; + + ret = btrfs_encoded_read(&kiocb, &iter, &args, &cached_state, + &disk_bytenr, &disk_io_size); + + if (ret == -EIOCBQUEUED) { + bool unlocked = false; + u64 start, lockend, count; + + start = ALIGN_DOWN(kiocb.ki_pos, fs_info->sectorsize); + lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; + + if (args.compression) + count = disk_io_size; + else + count = args.len; + + ret = btrfs_encoded_read_regular(&kiocb, &iter, start, lockend, + &cached_state, disk_bytenr, + disk_io_size, count, + args.compression, &unlocked); + + if (!unlocked) { + btrfs_unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + } + } + + if (ret >= 0) { + fsnotify_access(file); + if (copy_to_user(argp + copy_end, + (char *)&args + copy_end_kernel, + sizeof(args) - copy_end_kernel)) + ret = -EFAULT; + } + +out_iov: + kfree(iov); +out_acct: + if (ret > 0) + add_rchar(current, ret); + inc_syscr(current); + return ret; +} + +static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat) +{ + struct btrfs_ioctl_encoded_io_args args; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov = iovstack; + struct iov_iter iter; + loff_t pos; + struct kiocb kiocb; + ssize_t ret; + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out_acct; + } + + if (!(file->f_mode & FMODE_WRITE)) { + ret = -EBADF; + goto out_acct; + } + + if (compat) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_encoded_io_args_32 args32; + + if (copy_from_user(&args32, argp, sizeof(args32))) { + ret = -EFAULT; + goto out_acct; + } + args.iov = compat_ptr(args32.iov); + args.iovcnt = args32.iovcnt; + args.offset = args32.offset; + args.flags = args32.flags; + args.len = args32.len; + args.unencoded_len = args32.unencoded_len; + args.unencoded_offset = args32.unencoded_offset; + args.compression = args32.compression; + args.encryption = args32.encryption; + memcpy(args.reserved, args32.reserved, sizeof(args.reserved)); +#else + return -ENOTTY; +#endif + } else { + if (copy_from_user(&args, argp, sizeof(args))) { + ret = -EFAULT; + goto out_acct; + } + } + + ret = -EINVAL; + if (args.flags != 0) + goto out_acct; + if (memchr_inv(args.reserved, 0, sizeof(args.reserved))) + goto out_acct; + if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE && + args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE) + goto out_acct; + if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES || + args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES) + goto out_acct; + if (args.unencoded_offset > args.unencoded_len) + goto out_acct; + if (args.len > args.unencoded_len - args.unencoded_offset) + goto out_acct; + + ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack), + &iov, &iter); + if (ret < 0) + goto out_acct; + + if (iov_iter_count(&iter) == 0) { + ret = 0; + goto out_iov; + } + pos = args.offset; + ret = rw_verify_area(WRITE, file, &pos, args.len); + if (ret < 0) + goto out_iov; + + init_sync_kiocb(&kiocb, file); + ret = kiocb_set_rw_flags(&kiocb, 0, WRITE); + if (ret) + goto out_iov; + kiocb.ki_pos = pos; + + file_start_write(file); + + ret = btrfs_do_write_iter(&kiocb, &iter, &args); + if (ret > 0) + fsnotify_modify(file); + + file_end_write(file); +out_iov: + kfree(iov); +out_acct: + if (ret > 0) + add_wchar(current, ret); + inc_syscw(current); + return ret; +} + +struct btrfs_uring_encoded_data { + struct btrfs_ioctl_encoded_io_args args; + struct iovec iovstack[UIO_FASTIOV]; + struct iovec *iov; + struct iov_iter iter; +}; + +/* + * Context that's attached to an encoded read io_uring command, in cmd->pdu. It + * contains the fields in btrfs_uring_read_extent that are necessary to finish + * off and cleanup the I/O in btrfs_uring_read_finished. + */ +struct btrfs_uring_priv { + struct io_uring_cmd *cmd; + struct page **pages; + unsigned long nr_pages; + struct kiocb iocb; + struct iovec *iov; + struct iov_iter iter; + struct extent_state *cached_state; + u64 count; + u64 start; + u64 lockend; + int err; + bool compressed; +}; + +struct io_btrfs_cmd { + struct btrfs_uring_encoded_data *data; + struct btrfs_uring_priv *priv; +}; + +static void btrfs_uring_read_finished(struct io_tw_req tw_req, io_tw_token_t tw) +{ + struct io_uring_cmd *cmd = io_uring_cmd_from_tw(tw_req); + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(cmd, struct io_btrfs_cmd); + struct btrfs_uring_priv *priv = bc->priv; + struct btrfs_inode *inode = BTRFS_I(file_inode(priv->iocb.ki_filp)); + struct extent_io_tree *io_tree = &inode->io_tree; + pgoff_t index; + u64 cur; + size_t page_offset; + ssize_t ret; + + /* The inode lock has already been acquired in btrfs_uring_read_extent. */ + btrfs_lockdep_inode_acquire(inode, i_rwsem); + + if (priv->err) { + ret = priv->err; + goto out; + } + + if (priv->compressed) { + index = 0; + page_offset = 0; + } else { + index = (priv->iocb.ki_pos - priv->start) >> PAGE_SHIFT; + page_offset = offset_in_page(priv->iocb.ki_pos - priv->start); + } + cur = 0; + while (cur < priv->count) { + size_t bytes = min_t(size_t, priv->count - cur, PAGE_SIZE - page_offset); + + if (copy_page_to_iter(priv->pages[index], page_offset, bytes, + &priv->iter) != bytes) { + ret = -EFAULT; + goto out; + } + + index++; + cur += bytes; + page_offset = 0; + } + ret = priv->count; + +out: + btrfs_unlock_extent(io_tree, priv->start, priv->lockend, &priv->cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + + io_uring_cmd_done(cmd, ret, IO_URING_CMD_TASK_WORK_ISSUE_FLAGS); + add_rchar(current, ret); + + for (index = 0; index < priv->nr_pages; index++) + __free_page(priv->pages[index]); + + kfree(priv->pages); + kfree(priv->iov); + kfree(priv); + kfree(bc->data); +} + +void btrfs_uring_read_extent_endio(void *ctx, int err) +{ + struct btrfs_uring_priv *priv = ctx; + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(priv->cmd, struct io_btrfs_cmd); + + priv->err = err; + bc->priv = priv; + + io_uring_cmd_complete_in_task(priv->cmd, btrfs_uring_read_finished); +} + +static int btrfs_uring_read_extent(struct kiocb *iocb, struct iov_iter *iter, + u64 start, u64 lockend, + struct extent_state *cached_state, + u64 disk_bytenr, u64 disk_io_size, + size_t count, bool compressed, + struct iovec *iov, struct io_uring_cmd *cmd) +{ + struct btrfs_inode *inode = BTRFS_I(file_inode(iocb->ki_filp)); + struct extent_io_tree *io_tree = &inode->io_tree; + struct page **pages = NULL; + struct btrfs_uring_priv *priv = NULL; + unsigned long nr_pages; + int ret; + + nr_pages = DIV_ROUND_UP(disk_io_size, PAGE_SIZE); + pages = kzalloc_objs(struct page *, nr_pages, GFP_NOFS); + if (!pages) + return -ENOMEM; + ret = btrfs_alloc_page_array(nr_pages, pages, GFP_NOFS); + if (ret) { + ret = -ENOMEM; + goto out_fail; + } + + priv = kmalloc_obj(*priv, GFP_NOFS); + if (!priv) { + ret = -ENOMEM; + goto out_fail; + } + + priv->iocb = *iocb; + priv->iov = iov; + priv->iter = *iter; + priv->count = count; + priv->cmd = cmd; + priv->cached_state = cached_state; + priv->compressed = compressed; + priv->nr_pages = nr_pages; + priv->pages = pages; + priv->start = start; + priv->lockend = lockend; + priv->err = 0; + + ret = btrfs_encoded_read_regular_fill_pages(inode, disk_bytenr, + disk_io_size, pages, priv); + if (ret && ret != -EIOCBQUEUED) + goto out_fail; + + /* + * If we return -EIOCBQUEUED, we're deferring the cleanup to + * btrfs_uring_read_finished(), which will handle unlocking the extent + * and inode and freeing the allocations. + */ + + /* + * We're returning to userspace with the inode lock held, and that's + * okay - it'll get unlocked in a worker thread. Call + * btrfs_lockdep_inode_release() to avoid confusing lockdep. + */ + btrfs_lockdep_inode_release(inode, i_rwsem); + + return -EIOCBQUEUED; + +out_fail: + btrfs_unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + kfree(priv); + for (int i = 0; i < nr_pages; i++) { + if (pages[i]) + __free_page(pages[i]); + } + kfree(pages); + return ret; +} + +static int btrfs_uring_encoded_read(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + struct file *file = cmd->file; + struct btrfs_inode *inode = BTRFS_I(file->f_inode); + struct extent_io_tree *io_tree = &inode->io_tree; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args, flags); + size_t copy_end; + int ret; + u64 disk_bytenr, disk_io_size; + loff_t pos; + struct kiocb kiocb; + struct extent_state *cached_state = NULL; + u64 start, lockend; + void __user *sqe_addr; + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(cmd, struct io_btrfs_cmd); + struct btrfs_uring_encoded_data *data = NULL; + + if (cmd->flags & IORING_URING_CMD_REISSUE) + data = bc->data; + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out_acct; + } + sqe_addr = u64_to_user_ptr(READ_ONCE(cmd->sqe->addr)); + + if (issue_flags & IO_URING_F_COMPAT) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32, flags); +#else + ret = -ENOTTY; + goto out_acct; +#endif + } else { + copy_end = copy_end_kernel; + } + + if (!data) { + data = kzalloc_obj(*data, GFP_NOFS); + if (!data) { + ret = -ENOMEM; + goto out_acct; + } + + bc->data = data; + + if (issue_flags & IO_URING_F_COMPAT) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_encoded_io_args_32 args32; + + if (copy_from_user(&args32, sqe_addr, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + + data->args.iov = compat_ptr(args32.iov); + data->args.iovcnt = args32.iovcnt; + data->args.offset = args32.offset; + data->args.flags = args32.flags; +#endif + } else { + if (copy_from_user(&data->args, sqe_addr, copy_end)) { + ret = -EFAULT; + goto out_acct; + } + } + + if (data->args.flags != 0) { + ret = -EINVAL; + goto out_acct; + } + + data->iov = data->iovstack; + ret = import_iovec(ITER_DEST, data->args.iov, data->args.iovcnt, + ARRAY_SIZE(data->iovstack), &data->iov, + &data->iter); + if (ret < 0) + goto out_acct; + + if (iov_iter_count(&data->iter) == 0) { + ret = 0; + goto out_free; + } + } + + pos = data->args.offset; + ret = rw_verify_area(READ, file, &pos, data->args.len); + if (ret < 0) + goto out_free; + + init_sync_kiocb(&kiocb, file); + kiocb.ki_pos = pos; + + if (issue_flags & IO_URING_F_NONBLOCK) + kiocb.ki_flags |= IOCB_NOWAIT; + + start = ALIGN_DOWN(pos, fs_info->sectorsize); + lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; + + ret = btrfs_encoded_read(&kiocb, &data->iter, &data->args, &cached_state, + &disk_bytenr, &disk_io_size); + if (ret == -EAGAIN) + goto out_acct; + if (ret < 0 && ret != -EIOCBQUEUED) + goto out_free; + + file_accessed(file); + + if (copy_to_user(sqe_addr + copy_end, + (const char *)&data->args + copy_end_kernel, + sizeof(data->args) - copy_end_kernel)) { + if (ret == -EIOCBQUEUED) { + btrfs_unlock_extent(io_tree, start, lockend, &cached_state); + btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); + } + ret = -EFAULT; + goto out_free; + } + + if (ret == -EIOCBQUEUED) { + u64 count = min_t(u64, iov_iter_count(&data->iter), disk_io_size); + + /* Match ioctl by not returning past EOF if uncompressed. */ + if (!data->args.compression) + count = min_t(u64, count, data->args.len); + + ret = btrfs_uring_read_extent(&kiocb, &data->iter, start, lockend, + cached_state, disk_bytenr, disk_io_size, + count, data->args.compression, + data->iov, cmd); + + goto out_acct; + } + +out_free: + kfree(data->iov); + +out_acct: + if (ret > 0) + add_rchar(current, ret); + inc_syscr(current); + + if (ret != -EIOCBQUEUED && ret != -EAGAIN) + kfree(data); + + return ret; +} + +static int btrfs_uring_encoded_write(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + struct file *file = cmd->file; + loff_t pos; + struct kiocb kiocb; + ssize_t ret; + void __user *sqe_addr; + struct io_btrfs_cmd *bc = io_uring_cmd_to_pdu(cmd, struct io_btrfs_cmd); + struct btrfs_uring_encoded_data *data = NULL; + + if (cmd->flags & IORING_URING_CMD_REISSUE) + data = bc->data; + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out_acct; + } + sqe_addr = u64_to_user_ptr(READ_ONCE(cmd->sqe->addr)); + + if (!(file->f_mode & FMODE_WRITE)) { + ret = -EBADF; + goto out_acct; + } + + if (!data) { + data = kzalloc_obj(*data, GFP_NOFS); + if (!data) { + ret = -ENOMEM; + goto out_acct; + } + + bc->data = data; + + if (issue_flags & IO_URING_F_COMPAT) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_encoded_io_args_32 args32; + + if (copy_from_user(&args32, sqe_addr, sizeof(args32))) { + ret = -EFAULT; + goto out_acct; + } + data->args.iov = compat_ptr(args32.iov); + data->args.iovcnt = args32.iovcnt; + data->args.offset = args32.offset; + data->args.flags = args32.flags; + data->args.len = args32.len; + data->args.unencoded_len = args32.unencoded_len; + data->args.unencoded_offset = args32.unencoded_offset; + data->args.compression = args32.compression; + data->args.encryption = args32.encryption; + memcpy(data->args.reserved, args32.reserved, + sizeof(data->args.reserved)); +#else + ret = -ENOTTY; + goto out_acct; +#endif + } else { + if (copy_from_user(&data->args, sqe_addr, sizeof(data->args))) { + ret = -EFAULT; + goto out_acct; + } + } + + ret = -EINVAL; + if (data->args.flags != 0) + goto out_acct; + if (memchr_inv(data->args.reserved, 0, sizeof(data->args.reserved))) + goto out_acct; + if (data->args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE && + data->args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE) + goto out_acct; + if (data->args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES || + data->args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES) + goto out_acct; + if (data->args.unencoded_offset > data->args.unencoded_len) + goto out_acct; + if (data->args.len > data->args.unencoded_len - data->args.unencoded_offset) + goto out_acct; + + data->iov = data->iovstack; + ret = import_iovec(ITER_SOURCE, data->args.iov, data->args.iovcnt, + ARRAY_SIZE(data->iovstack), &data->iov, + &data->iter); + if (ret < 0) + goto out_acct; + + if (iov_iter_count(&data->iter) == 0) { + ret = 0; + goto out_iov; + } + } + + if (issue_flags & IO_URING_F_NONBLOCK) { + ret = -EAGAIN; + goto out_acct; + } + + pos = data->args.offset; + ret = rw_verify_area(WRITE, file, &pos, data->args.len); + if (ret < 0) + goto out_iov; + + init_sync_kiocb(&kiocb, file); + ret = kiocb_set_rw_flags(&kiocb, 0, WRITE); + if (ret) + goto out_iov; + kiocb.ki_pos = pos; + + file_start_write(file); + + ret = btrfs_do_write_iter(&kiocb, &data->iter, &data->args); + if (ret > 0) + fsnotify_modify(file); + + file_end_write(file); +out_iov: + kfree(data->iov); +out_acct: + if (ret > 0) + add_wchar(current, ret); + inc_syscw(current); + + if (ret != -EAGAIN) + kfree(data); + return ret; +} + +int btrfs_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) +{ + if (btrfs_is_shutdown(inode_to_fs_info(file_inode(cmd->file)))) + return -EIO; + + switch (cmd->cmd_op) { + case BTRFS_IOC_ENCODED_READ: +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_ENCODED_READ_32: +#endif + return btrfs_uring_encoded_read(cmd, issue_flags); + + case BTRFS_IOC_ENCODED_WRITE: +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_ENCODED_WRITE_32: +#endif + return btrfs_uring_encoded_write(cmd, issue_flags); + } + + return -EINVAL; +} + +static int btrfs_ioctl_subvol_sync(struct btrfs_fs_info *fs_info, void __user *argp) +{ + struct btrfs_root *root; + struct btrfs_ioctl_subvol_wait args = { 0 }; + signed long sched_ret; + int refs; + u64 root_flags; + bool wait_for_deletion = false; + bool found = false; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + + switch (args.mode) { + case BTRFS_SUBVOL_SYNC_WAIT_FOR_QUEUED: + /* + * Wait for the first one deleted that waits until all previous + * are cleaned. + */ + spin_lock(&fs_info->trans_lock); + if (!list_empty(&fs_info->dead_roots)) { + root = list_last_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + found = true; + } + spin_unlock(&fs_info->trans_lock); + if (!found) + return -ENOENT; + + fallthrough; + case BTRFS_SUBVOL_SYNC_WAIT_FOR_ONE: + if ((0 < args.subvolid && args.subvolid < BTRFS_FIRST_FREE_OBJECTID) || + BTRFS_LAST_FREE_OBJECTID < args.subvolid) + return -EINVAL; + break; + case BTRFS_SUBVOL_SYNC_COUNT: + spin_lock(&fs_info->trans_lock); + args.count = list_count_nodes(&fs_info->dead_roots); + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + case BTRFS_SUBVOL_SYNC_PEEK_FIRST: + spin_lock(&fs_info->trans_lock); + /* Last in the list was deleted first. */ + if (!list_empty(&fs_info->dead_roots)) { + root = list_last_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + } else { + args.subvolid = 0; + } + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + case BTRFS_SUBVOL_SYNC_PEEK_LAST: + spin_lock(&fs_info->trans_lock); + /* First in the list was deleted last. */ + if (!list_empty(&fs_info->dead_roots)) { + root = list_first_entry(&fs_info->dead_roots, + struct btrfs_root, root_list); + args.subvolid = btrfs_root_id(root); + } else { + args.subvolid = 0; + } + spin_unlock(&fs_info->trans_lock); + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + default: + return -EINVAL; + } + + /* 32bit limitation: fs_roots_radix key is not wide enough. */ + if (sizeof(unsigned long) != sizeof(u64) && args.subvolid > U32_MAX) + return -EOVERFLOW; + + while (1) { + /* Wait for the specific one. */ + if (down_read_interruptible(&fs_info->subvol_sem) == -EINTR) + return -EINTR; + refs = -1; + spin_lock(&fs_info->fs_roots_radix_lock); + root = radix_tree_lookup(&fs_info->fs_roots_radix, + (unsigned long)args.subvolid); + if (root) { + spin_lock(&root->root_item_lock); + refs = btrfs_root_refs(&root->root_item); + root_flags = btrfs_root_flags(&root->root_item); + spin_unlock(&root->root_item_lock); + } + spin_unlock(&fs_info->fs_roots_radix_lock); + up_read(&fs_info->subvol_sem); + + /* Subvolume does not exist. */ + if (!root) + return -ENOENT; + + /* Subvolume not deleted at all. */ + if (refs > 0) + return -EEXIST; + /* We've waited and now the subvolume is gone. */ + if (wait_for_deletion && refs == -1) { + /* Return the one we waited for as the last one. */ + if (copy_to_user(argp, &args, sizeof(args))) + return -EFAULT; + return 0; + } + + /* Subvolume not found on the first try (deleted or never existed). */ + if (refs == -1) + return -ENOENT; + + wait_for_deletion = true; + ASSERT(root_flags & BTRFS_ROOT_SUBVOL_DEAD, "root_flags=0x%llx", + root_flags); + sched_ret = schedule_timeout_interruptible(HZ); + /* Early wake up or error. */ + if (sched_ret != 0) + return -EINTR; + } + + return 0; +} + +static int btrfs_ioctl_shutdown(struct btrfs_fs_info *fs_info, unsigned long arg) +{ + int ret = 0; + u32 flags; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (get_user(flags, (u32 __user *)arg)) + return -EFAULT; + + if (flags >= BTRFS_SHUTDOWN_FLAGS_LAST) + return -EINVAL; + + if (btrfs_is_shutdown(fs_info)) + return 0; + + switch (flags) { + case BTRFS_SHUTDOWN_FLAGS_LOGFLUSH: + case BTRFS_SHUTDOWN_FLAGS_DEFAULT: + ret = freeze_super(fs_info->sb, FREEZE_HOLDER_KERNEL, NULL); + if (ret) + return ret; + btrfs_force_shutdown(fs_info); + ret = thaw_super(fs_info->sb, FREEZE_HOLDER_KERNEL, NULL); + if (ret) + return ret; + break; + case BTRFS_SHUTDOWN_FLAGS_NOLOGFLUSH: + btrfs_force_shutdown(fs_info); + break; + default: + ret = -EINVAL; + break; + } + return ret; +} + +#define GET_CSUMS_BUF_MAX SZ_16M + +static int copy_csums_to_user(struct btrfs_fs_info *fs_info, u64 disk_bytenr, + u64 len, u8 __user *buf) +{ + struct btrfs_root *csum_root; + struct btrfs_ordered_sum *sums; + LIST_HEAD(list); + const u32 csum_size = fs_info->csum_size; + int ret; + + csum_root = btrfs_csum_root(fs_info, disk_bytenr); + if (unlikely(!csum_root)) { + btrfs_err(fs_info, "missing csum root for extent at bytenr %llu", disk_bytenr); + return -EUCLEAN; + } + + ret = btrfs_lookup_csums_list(csum_root, disk_bytenr, + disk_bytenr + len - 1, &list, false); + if (ret < 0) + return ret; + + ret = 0; + while (!list_empty(&list)) { + u64 offset; + size_t copy_size; + + sums = list_first_entry(&list, struct btrfs_ordered_sum, list); + list_del(&sums->list); + + offset = ((sums->logical - disk_bytenr) >> fs_info->sectorsize_bits) * csum_size; + copy_size = (sums->len >> fs_info->sectorsize_bits) * csum_size; + + if (copy_to_user(buf + offset, sums->sums, copy_size)) { + kfree(sums); + ret = -EFAULT; + goto out; + } + + kfree(sums); + } + +out: + while (!list_empty(&list)) { + sums = list_first_entry(&list, struct btrfs_ordered_sum, list); + list_del(&sums->list); + kfree(sums); + } + return ret; +} + +static int btrfs_ioctl_get_csums(struct file *file, void __user *argp) +{ + struct inode *vfs_inode = file_inode(file); + struct btrfs_inode *inode = BTRFS_I(vfs_inode); + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct btrfs_root *root = inode->root; + struct btrfs_ioctl_get_csums_args args = { 0 }; + BTRFS_PATH_AUTO_FREE(path); + const u64 ino = btrfs_ino(inode); + const u32 csum_size = fs_info->csum_size; + u8 __user *ubuf; + u64 buf_limit; + u64 buf_used = 0; + u64 cur_offset; + u64 end_offset; + u64 prev_extent_end; + struct btrfs_key key; + int ret; + + if (!(file->f_mode & FMODE_READ)) + return -EBADF; + + if (!S_ISREG(vfs_inode->i_mode)) + return -EINVAL; + + if (copy_from_user(&args, argp, sizeof(args))) + return -EFAULT; + + if (!IS_ALIGNED(args.offset, fs_info->sectorsize) || + !IS_ALIGNED(args.length, fs_info->sectorsize)) + return -EINVAL; + if (args.length == 0) + return -EINVAL; + if (args.offset + args.length < args.offset) + return -EOVERFLOW; + if (args.flags != 0) + return -EINVAL; + if (args.buf_size < sizeof(struct btrfs_ioctl_get_csums_entry)) + return -EINVAL; + + buf_limit = min_t(u64, args.buf_size, GET_CSUMS_BUF_MAX); + ubuf = (u8 __user *)(argp + offsetof(struct btrfs_ioctl_get_csums_args, buf)); + + if (clear_user(ubuf, buf_limit)) + return -EFAULT; + + cur_offset = args.offset; + end_offset = args.offset + args.length; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = btrfs_wait_ordered_range(inode, cur_offset, args.length); + if (ret) + return ret; + + ret = down_read_interruptible(&vfs_inode->i_rwsem); + if (ret) + return ret; + + ret = btrfs_wait_ordered_range(inode, cur_offset, args.length); + if (ret) + goto out_unlock; + + /* NODATASUM early exit. */ + if (inode->flags & BTRFS_INODE_NODATASUM) { + struct btrfs_ioctl_get_csums_entry entry = { + .offset = cur_offset, + .length = end_offset - cur_offset, + .type = BTRFS_GET_CSUMS_NODATASUM, + }; + + if (copy_to_user(ubuf, &entry, sizeof(entry))) { + ret = -EFAULT; + goto out_unlock; + } + + buf_used = sizeof(entry); + cur_offset = end_offset; + goto done; + } + + prev_extent_end = cur_offset; + + while (cur_offset < end_offset) { + struct btrfs_file_extent_item *ei; + struct extent_buffer *leaf; + struct btrfs_ioctl_get_csums_entry entry = { 0 }; + u64 extent_end; + u64 disk_bytenr = 0; + u64 extent_offset = 0; + u64 range_start, range_len; + u64 entry_csum_size; + u64 key_offset; + int extent_type; + u8 compression; + u8 encryption; + + /* Search for the extent at or before cur_offset. */ + key.objectid = ino; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = cur_offset; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto out_unlock; + + if (ret > 0 && path->slots[0] > 0) { + btrfs_item_key_to_cpu(path->nodes[0], &key, + path->slots[0] - 1); + if (key.objectid == ino && key.type == BTRFS_EXTENT_DATA_KEY) { + path->slots[0]--; + if (btrfs_file_extent_end(path) <= cur_offset) + path->slots[0]++; + } + } + + if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + goto out_unlock; + if (ret > 0) { + ret = 0; + btrfs_release_path(path); + break; + } + } + + leaf = path->nodes[0]; + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY) { + btrfs_release_path(path); + break; + } + + extent_end = btrfs_file_extent_end(path); + key_offset = key.offset; + + /* Read extent fields before releasing the path. */ + ei = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); + extent_type = btrfs_file_extent_type(leaf, ei); + compression = btrfs_file_extent_compression(leaf, ei); + encryption = btrfs_file_extent_encryption(leaf, ei); + + if (extent_type != BTRFS_FILE_EXTENT_INLINE) { + disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, ei); + if (disk_bytenr && compression == BTRFS_COMPRESS_NONE) + extent_offset = btrfs_file_extent_offset(leaf, ei); + } + + btrfs_release_path(path); + + /* Implicit hole (NO_HOLES feature). */ + if (prev_extent_end < key_offset) { + u64 hole_end = min(key_offset, end_offset); + u64 hole_len = hole_end - prev_extent_end; + + if (prev_extent_end >= cur_offset) { + entry.offset = prev_extent_end; + entry.length = hole_len; + entry.type = BTRFS_GET_CSUMS_ZEROED; + + if (buf_used + sizeof(entry) > buf_limit) + goto done; + if (copy_to_user(ubuf + buf_used, &entry, sizeof(entry))) { + ret = -EFAULT; + goto out_unlock; + } + buf_used += sizeof(entry); + cur_offset = hole_end; + } + + if (key_offset >= end_offset) { + cur_offset = end_offset; + break; + } + } + + /* Clamp to our query range. */ + range_start = max(cur_offset, key_offset); + range_len = min(extent_end, end_offset) - range_start; + + entry.offset = range_start; + entry.length = range_len; + + if (extent_type == BTRFS_FILE_EXTENT_INLINE) { + entry.type = BTRFS_GET_CSUMS_INLINE; + if (compression != BTRFS_COMPRESS_NONE) + entry.type |= BTRFS_GET_CSUMS_COMPRESSED; + if (encryption != 0) + entry.type |= BTRFS_GET_CSUMS_ENCRYPTED; + entry_csum_size = 0; + } else if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { + entry.type = BTRFS_GET_CSUMS_ZEROED; + entry_csum_size = 0; + } else { + /* BTRFS_FILE_EXTENT_REG */ + if (disk_bytenr == 0) { + /* Explicit hole. */ + entry.type = BTRFS_GET_CSUMS_ZEROED; + entry_csum_size = 0; + } else if (encryption != 0 || compression != BTRFS_COMPRESS_NONE) { + entry.type = 0; + if (encryption != 0) + entry.type |= BTRFS_GET_CSUMS_ENCRYPTED; + if (compression != BTRFS_COMPRESS_NONE) + entry.type |= BTRFS_GET_CSUMS_COMPRESSED; + entry_csum_size = 0; + } else { + entry.type = BTRFS_GET_CSUMS_HAS_CSUMS; + entry_csum_size = (range_len >> fs_info->sectorsize_bits) * csum_size; + } + } + + /* Check if this entry (+ csum data) fits in the buffer. */ + if (buf_used + sizeof(entry) + entry_csum_size > buf_limit) { + if (buf_used == 0) { + ret = -EOVERFLOW; + goto out_unlock; + } + goto done; + } + + if (copy_to_user(ubuf + buf_used, &entry, sizeof(entry))) { + ret = -EFAULT; + goto out_unlock; + } + buf_used += sizeof(entry); + + if (entry.type == BTRFS_GET_CSUMS_HAS_CSUMS) { + ret = copy_csums_to_user(fs_info, + disk_bytenr + extent_offset + (range_start - key_offset), + range_len, ubuf + buf_used); + if (ret) + goto out_unlock; + buf_used += entry_csum_size; + } + + cur_offset = range_start + range_len; + prev_extent_end = extent_end; + + if (fatal_signal_pending(current)) { + if (buf_used == 0) { + ret = -EINTR; + goto out_unlock; + } + goto done; + } + + cond_resched(); + } + + /* Handle trailing implicit hole. */ + if (cur_offset < end_offset) { + struct btrfs_ioctl_get_csums_entry entry = { + .offset = prev_extent_end, + .length = end_offset - prev_extent_end, + .type = BTRFS_GET_CSUMS_ZEROED, + }; + + if (buf_used + sizeof(entry) <= buf_limit) { + if (copy_to_user(ubuf + buf_used, &entry, sizeof(entry))) { + ret = -EFAULT; + goto out_unlock; + } + buf_used += sizeof(entry); + cur_offset = end_offset; + } + } + +done: + args.offset = cur_offset; + args.length = (cur_offset < end_offset) ? end_offset - cur_offset : 0; + args.buf_size = buf_used; + + if (copy_to_user(argp, &args, sizeof(args))) + ret = -EFAULT; + +out_unlock: + up_read(&vfs_inode->i_rwsem); + return ret; +} + +long btrfs_ioctl(struct file *file, unsigned int + cmd, unsigned long arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + struct btrfs_root *root = BTRFS_I(inode)->root; + void __user *argp = (void __user *)arg; + + switch (cmd) { + case FS_IOC_GETVERSION: + return btrfs_ioctl_getversion(inode, argp); + case FS_IOC_GETFSLABEL: + return btrfs_ioctl_get_fslabel(fs_info, argp); + case FS_IOC_SETFSLABEL: + return btrfs_ioctl_set_fslabel(file, argp); + case FITRIM: + return btrfs_ioctl_fitrim(fs_info, argp); + case BTRFS_IOC_SNAP_CREATE: + return btrfs_ioctl_snap_create(file, argp, false); + case BTRFS_IOC_SNAP_CREATE_V2: + return btrfs_ioctl_snap_create_v2(file, argp, false); + case BTRFS_IOC_SUBVOL_CREATE: + return btrfs_ioctl_snap_create(file, argp, true); + case BTRFS_IOC_SUBVOL_CREATE_V2: + return btrfs_ioctl_snap_create_v2(file, argp, true); + case BTRFS_IOC_SNAP_DESTROY: + return btrfs_ioctl_snap_destroy(file, argp, false); + case BTRFS_IOC_SNAP_DESTROY_V2: + return btrfs_ioctl_snap_destroy(file, argp, true); + case BTRFS_IOC_SUBVOL_GETFLAGS: + return btrfs_ioctl_subvol_getflags(BTRFS_I(inode), argp); + case BTRFS_IOC_SUBVOL_SETFLAGS: + return btrfs_ioctl_subvol_setflags(file, argp); + case BTRFS_IOC_DEFAULT_SUBVOL: + return btrfs_ioctl_default_subvol(file, argp); + case BTRFS_IOC_DEFRAG: + return btrfs_ioctl_defrag(file, NULL); + case BTRFS_IOC_DEFRAG_RANGE: + return btrfs_ioctl_defrag(file, argp); + case BTRFS_IOC_RESIZE: + return btrfs_ioctl_resize(file, argp); + case BTRFS_IOC_ADD_DEV: + return btrfs_ioctl_add_dev(fs_info, argp); + case BTRFS_IOC_RM_DEV: + return btrfs_ioctl_rm_dev(file, argp); + case BTRFS_IOC_RM_DEV_V2: + return btrfs_ioctl_rm_dev_v2(file, argp); + case BTRFS_IOC_FS_INFO: + return btrfs_ioctl_fs_info(fs_info, argp); + case BTRFS_IOC_DEV_INFO: + return btrfs_ioctl_dev_info(fs_info, argp); + case BTRFS_IOC_TREE_SEARCH: + return btrfs_ioctl_tree_search(root, argp); + case BTRFS_IOC_TREE_SEARCH_V2: + return btrfs_ioctl_tree_search_v2(root, argp); + case BTRFS_IOC_INO_LOOKUP: + return btrfs_ioctl_ino_lookup(root, argp); + case BTRFS_IOC_INO_PATHS: + return btrfs_ioctl_ino_to_path(root, argp); + case BTRFS_IOC_LOGICAL_INO: + return btrfs_ioctl_logical_to_ino(fs_info, argp, 1); + case BTRFS_IOC_LOGICAL_INO_V2: + return btrfs_ioctl_logical_to_ino(fs_info, argp, 2); + case BTRFS_IOC_SPACE_INFO: + return btrfs_ioctl_space_info(fs_info, argp); + case BTRFS_IOC_SYNC: { + int ret; + + ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false); + if (ret) + return ret; + ret = btrfs_sync_fs(inode->i_sb, 1); + /* + * There may be work for the cleaner kthread to do (subvolume + * deletion, delayed iputs, defrag inodes, etc), so wake it up. + */ + wake_up_process(fs_info->cleaner_kthread); + return ret; + } + case BTRFS_IOC_START_SYNC: + return btrfs_ioctl_start_sync(root, argp); + case BTRFS_IOC_WAIT_SYNC: + return btrfs_ioctl_wait_sync(fs_info, argp); + case BTRFS_IOC_SCRUB: + return btrfs_ioctl_scrub(file, argp); + case BTRFS_IOC_SCRUB_CANCEL: + return btrfs_ioctl_scrub_cancel(fs_info); + case BTRFS_IOC_SCRUB_PROGRESS: + return btrfs_ioctl_scrub_progress(fs_info, argp); + case BTRFS_IOC_BALANCE_V2: + return btrfs_ioctl_balance(file, argp); + case BTRFS_IOC_BALANCE_CTL: + return btrfs_ioctl_balance_ctl(fs_info, arg); + case BTRFS_IOC_BALANCE_PROGRESS: + return btrfs_ioctl_balance_progress(fs_info, argp); + case BTRFS_IOC_SET_RECEIVED_SUBVOL: + return btrfs_ioctl_set_received_subvol(file, argp); +#ifdef CONFIG_64BIT + case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: + return btrfs_ioctl_set_received_subvol_32(file, argp); +#endif + case BTRFS_IOC_SEND: + return _btrfs_ioctl_send(root, argp, false); +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_SEND_32: + return _btrfs_ioctl_send(root, argp, true); +#endif + case BTRFS_IOC_GET_DEV_STATS: + return btrfs_ioctl_get_dev_stats(fs_info, argp); + case BTRFS_IOC_QUOTA_CTL: + return btrfs_ioctl_quota_ctl(file, argp); + case BTRFS_IOC_QGROUP_ASSIGN: + return btrfs_ioctl_qgroup_assign(file, argp); + case BTRFS_IOC_QGROUP_CREATE: + return btrfs_ioctl_qgroup_create(file, argp); + case BTRFS_IOC_QGROUP_LIMIT: + return btrfs_ioctl_qgroup_limit(file, argp); + case BTRFS_IOC_QUOTA_RESCAN: + return btrfs_ioctl_quota_rescan(file, argp); + case BTRFS_IOC_QUOTA_RESCAN_STATUS: + return btrfs_ioctl_quota_rescan_status(fs_info, argp); + case BTRFS_IOC_QUOTA_RESCAN_WAIT: + return btrfs_ioctl_quota_rescan_wait(fs_info); + case BTRFS_IOC_DEV_REPLACE: + return btrfs_ioctl_dev_replace(fs_info, argp); + case BTRFS_IOC_GET_SUPPORTED_FEATURES: + return btrfs_ioctl_get_supported_features(argp); + case BTRFS_IOC_GET_FEATURES: + return btrfs_ioctl_get_features(fs_info, argp); + case BTRFS_IOC_SET_FEATURES: + return btrfs_ioctl_set_features(file, argp); + case BTRFS_IOC_GET_SUBVOL_INFO: + return btrfs_ioctl_get_subvol_info(inode, argp); +#ifdef CONFIG_64BIT + case BTRFS_IOC_GET_SUBVOL_INFO_32: + return btrfs_ioctl_get_subvol_info_32(inode, argp); +#endif + case BTRFS_IOC_GET_SUBVOL_ROOTREF: + return btrfs_ioctl_get_subvol_rootref(root, argp); + case BTRFS_IOC_INO_LOOKUP_USER: + return btrfs_ioctl_ino_lookup_user(file, argp); + case FS_IOC_ENABLE_VERITY: + return fsverity_ioctl_enable(file, (const void __user *)argp); + case FS_IOC_MEASURE_VERITY: + return fsverity_ioctl_measure(file, argp); + case FS_IOC_READ_VERITY_METADATA: + return fsverity_ioctl_read_metadata(file, argp); + case BTRFS_IOC_ENCODED_READ: + return btrfs_ioctl_encoded_read(file, argp, false); + case BTRFS_IOC_ENCODED_WRITE: + return btrfs_ioctl_encoded_write(file, argp, false); +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_ENCODED_READ_32: + return btrfs_ioctl_encoded_read(file, argp, true); + case BTRFS_IOC_ENCODED_WRITE_32: + return btrfs_ioctl_encoded_write(file, argp, true); +#endif + case BTRFS_IOC_SUBVOL_SYNC_WAIT: + return btrfs_ioctl_subvol_sync(fs_info, argp); + case BTRFS_IOC_SHUTDOWN: + return btrfs_ioctl_shutdown(fs_info, arg); + case BTRFS_IOC_GET_CSUMS: + return btrfs_ioctl_get_csums(file, argp); + } + + return -ENOTTY; +} + +#ifdef CONFIG_COMPAT +long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + /* + * These all access 32-bit values anyway so no further + * handling is necessary. + */ + switch (cmd) { + case FS_IOC32_GETVERSION: + cmd = FS_IOC_GETVERSION; + break; + } + + return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); +} +#endif |