diff options
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 6082 |
1 files changed, 6082 insertions, 0 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c new file mode 100644 index 000000000..717385b7f --- /dev/null +++ b/fs/btrfs/ioctl.c @@ -0,0 +1,6082 @@ +// 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 "ctree.h" +#include "disk-io.h" +#include "transaction.h" +#include "btrfs_inode.h" +#include "print-tree.h" +#include "volumes.h" +#include "locking.h" +#include "inode-map.h" +#include "backref.h" +#include "rcu-string.h" +#include "send.h" +#include "dev-replace.h" +#include "props.h" +#include "sysfs.h" +#include "qgroup.h" +#include "tree-log.h" +#include "compression.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) +#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 */ + __u64 reserved[4]; /* in */ +} __attribute__ ((__packed__)); + +#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \ + struct btrfs_ioctl_send_args_32) +#endif + +static int btrfs_clone(struct inode *src, struct inode *inode, + u64 off, u64 olen, u64 olen_aligned, u64 destoff, + int no_time_update); + +/* Mask out flags that are inappropriate for the given type of inode. */ +static unsigned int btrfs_mask_fsflags_for_type(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(unsigned int flags) +{ + unsigned int iflags = 0; + + 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 (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 inode *inode) +{ + struct btrfs_inode *binode = BTRFS_I(inode); + unsigned int new_fl = 0; + + if (binode->flags & BTRFS_INODE_SYNC) + new_fl |= S_SYNC; + if (binode->flags & BTRFS_INODE_IMMUTABLE) + new_fl |= S_IMMUTABLE; + if (binode->flags & BTRFS_INODE_APPEND) + new_fl |= S_APPEND; + if (binode->flags & BTRFS_INODE_NOATIME) + new_fl |= S_NOATIME; + if (binode->flags & BTRFS_INODE_DIRSYNC) + new_fl |= S_DIRSYNC; + + set_mask_bits(&inode->i_flags, + S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC, + new_fl); +} + +static int btrfs_ioctl_getflags(struct file *file, void __user *arg) +{ + struct btrfs_inode *binode = BTRFS_I(file_inode(file)); + unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags); + + if (copy_to_user(arg, &flags, sizeof(flags))) + return -EFAULT; + return 0; +} + +/* Check if @flags are a supported and valid set of FS_*_FL flags */ +static int check_fsflags(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; + + if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) + return -EINVAL; + + return 0; +} + +static int btrfs_ioctl_setflags(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_inode *binode = BTRFS_I(inode); + struct btrfs_root *root = binode->root; + struct btrfs_trans_handle *trans; + unsigned int fsflags, old_fsflags; + int ret; + u64 old_flags; + unsigned int old_i_flags; + umode_t mode; + + if (!inode_owner_or_capable(inode)) + return -EPERM; + + if (btrfs_root_readonly(root)) + return -EROFS; + + if (copy_from_user(&fsflags, arg, sizeof(fsflags))) + return -EFAULT; + + ret = check_fsflags(fsflags); + if (ret) + return ret; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + inode_lock(inode); + + old_flags = binode->flags; + old_i_flags = inode->i_flags; + mode = inode->i_mode; + + fsflags = btrfs_mask_fsflags_for_type(inode, fsflags); + old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags); + if ((fsflags ^ old_fsflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { + if (!capable(CAP_LINUX_IMMUTABLE)) { + ret = -EPERM; + goto out_unlock; + } + } + + if (fsflags & FS_SYNC_FL) + binode->flags |= BTRFS_INODE_SYNC; + else + binode->flags &= ~BTRFS_INODE_SYNC; + if (fsflags & FS_IMMUTABLE_FL) + binode->flags |= BTRFS_INODE_IMMUTABLE; + else + binode->flags &= ~BTRFS_INODE_IMMUTABLE; + if (fsflags & FS_APPEND_FL) + binode->flags |= BTRFS_INODE_APPEND; + else + binode->flags &= ~BTRFS_INODE_APPEND; + if (fsflags & FS_NODUMP_FL) + binode->flags |= BTRFS_INODE_NODUMP; + else + binode->flags &= ~BTRFS_INODE_NODUMP; + if (fsflags & FS_NOATIME_FL) + binode->flags |= BTRFS_INODE_NOATIME; + else + binode->flags &= ~BTRFS_INODE_NOATIME; + if (fsflags & FS_DIRSYNC_FL) + binode->flags |= BTRFS_INODE_DIRSYNC; + else + binode->flags &= ~BTRFS_INODE_DIRSYNC; + if (fsflags & FS_NOCOW_FL) { + if (S_ISREG(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->i_size == 0) + binode->flags |= BTRFS_INODE_NODATACOW + | BTRFS_INODE_NODATASUM; + } else { + binode->flags |= BTRFS_INODE_NODATACOW; + } + } else { + /* + * Revert back under same assumptions as above + */ + if (S_ISREG(mode)) { + if (inode->i_size == 0) + binode->flags &= ~(BTRFS_INODE_NODATACOW + | BTRFS_INODE_NODATASUM); + } else { + binode->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) { + binode->flags &= ~BTRFS_INODE_COMPRESS; + binode->flags |= BTRFS_INODE_NOCOMPRESS; + + ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); + if (ret && ret != -ENODATA) + goto out_drop; + } else if (fsflags & FS_COMPR_FL) { + const char *comp; + + binode->flags |= BTRFS_INODE_COMPRESS; + binode->flags &= ~BTRFS_INODE_NOCOMPRESS; + + comp = btrfs_compress_type2str(fs_info->compress_type); + if (!comp || comp[0] == 0) + comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB); + + ret = btrfs_set_prop(inode, "btrfs.compression", + comp, strlen(comp), 0); + if (ret) + goto out_drop; + + } else { + ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0); + if (ret && ret != -ENODATA) + goto out_drop; + binode->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); + } + + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_drop; + } + + btrfs_sync_inode_flags_to_i_flags(inode); + inode_inc_iversion(inode); + inode->i_ctime = current_time(inode); + ret = btrfs_update_inode(trans, root, inode); + + btrfs_end_transaction(trans); + out_drop: + if (ret) { + binode->flags = old_flags; + inode->i_flags = old_i_flags; + } + + out_unlock: + inode_unlock(inode); + mnt_drop_write_file(file); + return ret; +} + +/* + * Translate btrfs internal inode flags to xflags as expected by the + * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are + * silently dropped. + */ +static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags) +{ + unsigned int xflags = 0; + + if (flags & BTRFS_INODE_APPEND) + xflags |= FS_XFLAG_APPEND; + if (flags & BTRFS_INODE_IMMUTABLE) + xflags |= FS_XFLAG_IMMUTABLE; + if (flags & BTRFS_INODE_NOATIME) + xflags |= FS_XFLAG_NOATIME; + if (flags & BTRFS_INODE_NODUMP) + xflags |= FS_XFLAG_NODUMP; + if (flags & BTRFS_INODE_SYNC) + xflags |= FS_XFLAG_SYNC; + + return xflags; +} + +/* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */ +static int check_xflags(unsigned int flags) +{ + if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME | + FS_XFLAG_NODUMP | FS_XFLAG_SYNC)) + return -EOPNOTSUPP; + return 0; +} + +/* + * Set the xflags from the internal inode flags. The remaining items of fsxattr + * are zeroed. + */ +static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg) +{ + struct btrfs_inode *binode = BTRFS_I(file_inode(file)); + struct fsxattr fa; + + memset(&fa, 0, sizeof(fa)); + fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags); + + if (copy_to_user(arg, &fa, sizeof(fa))) + return -EFAULT; + + return 0; +} + +static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_inode *binode = BTRFS_I(inode); + struct btrfs_root *root = binode->root; + struct btrfs_trans_handle *trans; + struct fsxattr fa; + unsigned old_flags; + unsigned old_i_flags; + int ret = 0; + + if (!inode_owner_or_capable(inode)) + return -EPERM; + + if (btrfs_root_readonly(root)) + return -EROFS; + + memset(&fa, 0, sizeof(fa)); + if (copy_from_user(&fa, arg, sizeof(fa))) + return -EFAULT; + + ret = check_xflags(fa.fsx_xflags); + if (ret) + return ret; + + if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0) + return -EOPNOTSUPP; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + inode_lock(inode); + + old_flags = binode->flags; + old_i_flags = inode->i_flags; + + /* We need the capabilities to change append-only or immutable inode */ + if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) || + (fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) && + !capable(CAP_LINUX_IMMUTABLE)) { + ret = -EPERM; + goto out_unlock; + } + + if (fa.fsx_xflags & FS_XFLAG_SYNC) + binode->flags |= BTRFS_INODE_SYNC; + else + binode->flags &= ~BTRFS_INODE_SYNC; + if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE) + binode->flags |= BTRFS_INODE_IMMUTABLE; + else + binode->flags &= ~BTRFS_INODE_IMMUTABLE; + if (fa.fsx_xflags & FS_XFLAG_APPEND) + binode->flags |= BTRFS_INODE_APPEND; + else + binode->flags &= ~BTRFS_INODE_APPEND; + if (fa.fsx_xflags & FS_XFLAG_NODUMP) + binode->flags |= BTRFS_INODE_NODUMP; + else + binode->flags &= ~BTRFS_INODE_NODUMP; + if (fa.fsx_xflags & FS_XFLAG_NOATIME) + binode->flags |= BTRFS_INODE_NOATIME; + else + binode->flags &= ~BTRFS_INODE_NOATIME; + + /* 1 item for the inode */ + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_unlock; + } + + btrfs_sync_inode_flags_to_i_flags(inode); + inode_inc_iversion(inode); + inode->i_ctime = current_time(inode); + ret = btrfs_update_inode(trans, root, inode); + + btrfs_end_transaction(trans); + +out_unlock: + if (ret) { + binode->flags = old_flags; + inode->i_flags = old_i_flags; + } + + inode_unlock(inode); + mnt_drop_write_file(file); + + return ret; +} + +static int btrfs_ioctl_getversion(struct file *file, int __user *arg) +{ + struct inode *inode = file_inode(file); + + return put_user(inode->i_generation, arg); +} + +static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_device *device; + struct request_queue *q; + struct fstrim_range range; + u64 minlen = ULLONG_MAX; + u64 num_devices = 0; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* + * 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) + continue; + q = bdev_get_queue(device->bdev); + if (blk_queue_discard(q)) { + num_devices++; + minlen = min_t(u64, q->limits.discard_granularity, + 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->sb->s_blocksize) + return -EINVAL; + + range.minlen = max(range.minlen, minlen); + ret = btrfs_trim_fs(fs_info, &range); + if (ret < 0) + return ret; + + if (copy_to_user(arg, &range, sizeof(range))) + return -EFAULT; + + return 0; +} + +int btrfs_is_empty_uuid(u8 *uuid) +{ + int i; + + for (i = 0; i < BTRFS_UUID_SIZE; i++) { + if (uuid[i]) + return 0; + } + return 1; +} + +static noinline int create_subvol(struct inode *dir, + struct dentry *dentry, + const char *name, int namelen, + u64 *async_transid, + struct btrfs_qgroup_inherit *inherit) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); + struct btrfs_trans_handle *trans; + struct btrfs_key key; + struct btrfs_root_item *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 inode *inode; + int ret; + int err; + u64 objectid; + u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID; + u64 index = 0; + uuid_le new_uuid; + + root_item = kzalloc(sizeof(*root_item), GFP_KERNEL); + if (!root_item) + return -ENOMEM; + + ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid); + if (ret) + goto fail_free; + + /* + * 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)) { + ret = -ENOSPC; + goto fail_free; + } + + btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); + /* + * The same as the snapshot creation, please see the comment + * of create_snapshot(). + */ + ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false); + if (ret) + goto fail_free; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + btrfs_subvolume_release_metadata(fs_info, &block_rsv); + goto fail_free; + } + trans->block_rsv = &block_rsv; + trans->bytes_reserved = block_rsv.size; + + ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit); + if (ret) + goto fail; + + leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0); + if (IS_ERR(leaf)) { + ret = PTR_ERR(leaf); + goto fail; + } + + btrfs_mark_buffer_dirty(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)); + uuid_le_gen(&new_uuid); + memcpy(root_item->uuid, new_uuid.b, BTRFS_UUID_SIZE); + 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, new_dirid); + + key.objectid = objectid; + key.offset = 0; + key.type = BTRFS_ROOT_ITEM_KEY; + ret = btrfs_insert_root(trans, fs_info->tree_root, &key, + root_item); + if (ret) { + /* + * 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 without backreferences). Also no need to have + * the tree block locked since it is not in any tree at this + * point, so no other task can find it and use it. + */ + btrfs_free_tree_block(trans, root, leaf, 0, 1); + free_extent_buffer(leaf); + goto fail; + } + + free_extent_buffer(leaf); + leaf = NULL; + + key.offset = (u64)-1; + new_root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(new_root)) { + ret = PTR_ERR(new_root); + btrfs_abort_transaction(trans, ret); + goto fail; + } + + btrfs_record_root_in_trans(trans, new_root); + + ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid); + if (ret) { + /* We potentially lose an unused inode item here */ + btrfs_abort_transaction(trans, ret); + goto fail; + } + + mutex_lock(&new_root->objectid_mutex); + new_root->highest_objectid = new_dirid; + mutex_unlock(&new_root->objectid_mutex); + + /* + * insert the directory item + */ + ret = btrfs_set_inode_index(BTRFS_I(dir), &index); + if (ret) { + btrfs_abort_transaction(trans, ret); + goto fail; + } + + ret = btrfs_insert_dir_item(trans, root, + name, namelen, BTRFS_I(dir), &key, + BTRFS_FT_DIR, index); + if (ret) { + btrfs_abort_transaction(trans, ret); + goto fail; + } + + btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2); + ret = btrfs_update_inode(trans, root, dir); + if (ret) { + btrfs_abort_transaction(trans, ret); + goto fail; + } + + ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid, + btrfs_ino(BTRFS_I(dir)), index, name, namelen); + if (ret) { + btrfs_abort_transaction(trans, ret); + goto fail; + } + + ret = btrfs_uuid_tree_add(trans, root_item->uuid, + BTRFS_UUID_KEY_SUBVOL, objectid); + if (ret) + btrfs_abort_transaction(trans, ret); + +fail: + kfree(root_item); + trans->block_rsv = NULL; + trans->bytes_reserved = 0; + btrfs_subvolume_release_metadata(fs_info, &block_rsv); + + if (async_transid) { + *async_transid = trans->transid; + err = btrfs_commit_transaction_async(trans, 1); + if (err) + err = btrfs_commit_transaction(trans); + } else { + err = btrfs_commit_transaction(trans); + } + if (err && !ret) + ret = err; + + if (!ret) { + inode = btrfs_lookup_dentry(dir, dentry); + if (IS_ERR(inode)) + return PTR_ERR(inode); + d_instantiate(dentry, inode); + } + return ret; + +fail_free: + kfree(root_item); + return ret; +} + +static int create_snapshot(struct btrfs_root *root, struct inode *dir, + struct dentry *dentry, + u64 *async_transid, bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); + struct inode *inode; + struct btrfs_pending_snapshot *pending_snapshot; + struct btrfs_trans_handle *trans; + int ret; + bool snapshot_force_cow = false; + + if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state)) + return -EINVAL; + + pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL); + if (!pending_snapshot) + return -ENOMEM; + + pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item), + GFP_KERNEL); + pending_snapshot->path = btrfs_alloc_path(); + if (!pending_snapshot->root_item || !pending_snapshot->path) { + ret = -ENOMEM; + goto free_pending; + } + + /* + * Force new buffered writes to reserve space even when NOCOW is + * possible. This is to avoid later writeback (running dealloc) to + * fallback to COW mode and unexpectedly fail with ENOSPC. + */ + atomic_inc(&root->will_be_snapshotted); + smp_mb__after_atomic(); + /* wait for no snapshot writes */ + wait_event(root->subv_writers->wait, + percpu_counter_sum(&root->subv_writers->counter) == 0); + + ret = btrfs_start_delalloc_snapshot(root); + if (ret) + goto dec_and_free; + + /* + * 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); + snapshot_force_cow = true; + + btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1); + + btrfs_init_block_rsv(&pending_snapshot->block_rsv, + BTRFS_BLOCK_RSV_TEMP); + /* + * 1 - parent dir inode + * 2 - dir entries + * 1 - root item + * 2 - root ref/backref + * 1 - root of snapshot + * 1 - UUID item + */ + ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, + &pending_snapshot->block_rsv, 8, + false); + if (ret) + goto dec_and_free; + + pending_snapshot->dentry = dentry; + pending_snapshot->root = root; + pending_snapshot->readonly = readonly; + pending_snapshot->dir = dir; + pending_snapshot->inherit = inherit; + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto fail; + } + + spin_lock(&fs_info->trans_lock); + list_add(&pending_snapshot->list, + &trans->transaction->pending_snapshots); + spin_unlock(&fs_info->trans_lock); + if (async_transid) { + *async_transid = trans->transid; + ret = btrfs_commit_transaction_async(trans, 1); + if (ret) + ret = btrfs_commit_transaction(trans); + } else { + 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; +fail: + btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv); +dec_and_free: + if (snapshot_force_cow) + atomic_dec(&root->snapshot_force_cow); + if (atomic_dec_and_test(&root->will_be_snapshotted)) + wake_up_var(&root->will_be_snapshotted); +free_pending: + kfree(pending_snapshot->root_item); + btrfs_free_path(pending_snapshot->path); + kfree(pending_snapshot); + + return ret; +} + +/* copy of may_delete in fs/namei.c() + * Check whether we can remove a link victim from directory dir, check + * whether the type of victim is right. + * 1. We can't do it if dir is read-only (done in permission()) + * 2. We should have write and exec permissions on dir + * 3. We can't remove anything from append-only dir + * 4. We can't do anything with immutable dir (done in permission()) + * 5. If the sticky bit on dir is set we should either + * a. be owner of dir, or + * b. be owner of victim, or + * c. have CAP_FOWNER capability + * 6. If the victim is append-only or immutable we can't do anything with + * links pointing to it. + * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR. + * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR. + * 9. We can't remove a root or mountpoint. + * 10. We don't allow removal of NFS sillyrenamed files; it's handled by + * nfs_async_unlink(). + */ + +static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir) +{ + int error; + + if (d_really_is_negative(victim)) + return -ENOENT; + + BUG_ON(d_inode(victim->d_parent) != dir); + audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); + + error = inode_permission(dir, MAY_WRITE | MAY_EXEC); + if (error) + return error; + if (IS_APPEND(dir)) + return -EPERM; + if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) || + IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim))) + return -EPERM; + if (isdir) { + if (!d_is_dir(victim)) + return -ENOTDIR; + if (IS_ROOT(victim)) + return -EBUSY; + } else if (d_is_dir(victim)) + return -EISDIR; + if (IS_DEADDIR(dir)) + return -ENOENT; + if (victim->d_flags & DCACHE_NFSFS_RENAMED) + return -EBUSY; + return 0; +} + +/* copy of may_create in fs/namei.c() */ +static inline int btrfs_may_create(struct inode *dir, struct dentry *child) +{ + if (d_really_is_positive(child)) + return -EEXIST; + if (IS_DEADDIR(dir)) + return -ENOENT; + return inode_permission(dir, MAY_WRITE | MAY_EXEC); +} + +/* + * 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(const struct path *parent, + const char *name, int namelen, + struct btrfs_root *snap_src, + u64 *async_transid, bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + struct inode *dir = d_inode(parent->dentry); + struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb); + struct dentry *dentry; + int error; + + error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); + if (error == -EINTR) + return error; + + dentry = lookup_one_len(name, parent->dentry, namelen); + error = PTR_ERR(dentry); + if (IS_ERR(dentry)) + goto out_unlock; + + error = btrfs_may_create(dir, dentry); + if (error) + goto out_dput; + + /* + * even if this name doesn't exist, we may get hash collisions. + * check for them now when we can safely fail + */ + error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root, + dir->i_ino, name, + namelen); + if (error) + 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) { + error = create_snapshot(snap_src, dir, dentry, + async_transid, readonly, inherit); + } else { + error = create_subvol(dir, dentry, name, namelen, + async_transid, inherit); + } + if (!error) + fsnotify_mkdir(dir, dentry); +out_up_read: + up_read(&fs_info->subvol_sem); +out_dput: + dput(dentry); +out_unlock: + inode_unlock(dir); + return error; +} + +/* + * When we're defragging a range, we don't want to kick it off again + * if it is really just waiting for delalloc to send it down. + * If we find a nice big extent or delalloc range for the bytes in the + * file you want to defrag, we return 0 to let you know to skip this + * part of the file + */ +static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh) +{ + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + struct extent_map *em = NULL; + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + u64 end; + + read_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE); + read_unlock(&em_tree->lock); + + if (em) { + end = extent_map_end(em); + free_extent_map(em); + if (end - offset > thresh) + return 0; + } + /* if we already have a nice delalloc here, just stop */ + thresh /= 2; + end = count_range_bits(io_tree, &offset, offset + thresh, + thresh, EXTENT_DELALLOC, 1); + if (end >= thresh) + return 0; + return 1; +} + +/* + * helper function to walk through a file and find extents + * newer than a specific transid, and smaller than thresh. + * + * This is used by the defragging code to find new and small + * extents + */ +static int find_new_extents(struct btrfs_root *root, + struct inode *inode, u64 newer_than, + u64 *off, u32 thresh) +{ + struct btrfs_path *path; + struct btrfs_key min_key; + struct extent_buffer *leaf; + struct btrfs_file_extent_item *extent; + int type; + int ret; + u64 ino = btrfs_ino(BTRFS_I(inode)); + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + min_key.objectid = ino; + min_key.type = BTRFS_EXTENT_DATA_KEY; + min_key.offset = *off; + + while (1) { + ret = btrfs_search_forward(root, &min_key, path, newer_than); + if (ret != 0) + goto none; +process_slot: + if (min_key.objectid != ino) + goto none; + if (min_key.type != BTRFS_EXTENT_DATA_KEY) + goto none; + + leaf = path->nodes[0]; + extent = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + + type = btrfs_file_extent_type(leaf, extent); + if (type == BTRFS_FILE_EXTENT_REG && + btrfs_file_extent_num_bytes(leaf, extent) < thresh && + check_defrag_in_cache(inode, min_key.offset, thresh)) { + *off = min_key.offset; + btrfs_free_path(path); + return 0; + } + + path->slots[0]++; + if (path->slots[0] < btrfs_header_nritems(leaf)) { + btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]); + goto process_slot; + } + + if (min_key.offset == (u64)-1) + goto none; + + min_key.offset++; + btrfs_release_path(path); + } +none: + btrfs_free_path(path); + return -ENOENT; +} + +static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start) +{ + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + struct extent_map *em; + u64 len = PAGE_SIZE; + + /* + * hopefully we have this extent in the tree already, try without + * the full extent lock + */ + read_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, start, len); + read_unlock(&em_tree->lock); + + if (!em) { + struct extent_state *cached = NULL; + u64 end = start + len - 1; + + /* get the big lock and read metadata off disk */ + lock_extent_bits(io_tree, start, end, &cached); + em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0); + unlock_extent_cached(io_tree, start, end, &cached); + + if (IS_ERR(em)) + return NULL; + } + + return em; +} + +static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em) +{ + struct extent_map *next; + bool ret = true; + + /* this is the last extent */ + if (em->start + em->len >= i_size_read(inode)) + return false; + + next = defrag_lookup_extent(inode, em->start + em->len); + if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE) + ret = false; + else if ((em->block_start + em->block_len == next->block_start) && + (em->block_len > SZ_128K && next->block_len > SZ_128K)) + ret = false; + + free_extent_map(next); + return ret; +} + +static int should_defrag_range(struct inode *inode, u64 start, u32 thresh, + u64 *last_len, u64 *skip, u64 *defrag_end, + int compress) +{ + struct extent_map *em; + int ret = 1; + bool next_mergeable = true; + bool prev_mergeable = true; + + /* + * make sure that once we start defragging an extent, we keep on + * defragging it + */ + if (start < *defrag_end) + return 1; + + *skip = 0; + + em = defrag_lookup_extent(inode, start); + if (!em) + return 0; + + /* this will cover holes, and inline extents */ + if (em->block_start >= EXTENT_MAP_LAST_BYTE) { + ret = 0; + goto out; + } + + if (!*defrag_end) + prev_mergeable = false; + + next_mergeable = defrag_check_next_extent(inode, em); + /* + * we hit a real extent, if it is big or the next extent is not a + * real extent, don't bother defragging it + */ + if (!compress && (*last_len == 0 || *last_len >= thresh) && + (em->len >= thresh || (!next_mergeable && !prev_mergeable))) + ret = 0; +out: + /* + * last_len ends up being a counter of how many bytes we've defragged. + * every time we choose not to defrag an extent, we reset *last_len + * so that the next tiny extent will force a defrag. + * + * The end result of this is that tiny extents before a single big + * extent will force at least part of that big extent to be defragged. + */ + if (ret) { + *defrag_end = extent_map_end(em); + } else { + *last_len = 0; + *skip = extent_map_end(em); + *defrag_end = 0; + } + + free_extent_map(em); + return ret; +} + +/* + * it doesn't do much good to defrag one or two pages + * at a time. This pulls in a nice chunk of pages + * to COW and defrag. + * + * It also makes sure the delalloc code has enough + * dirty data to avoid making new small extents as part + * of the defrag + * + * It's a good idea to start RA on this range + * before calling this. + */ +static int cluster_pages_for_defrag(struct inode *inode, + struct page **pages, + unsigned long start_index, + unsigned long num_pages) +{ + unsigned long file_end; + u64 isize = i_size_read(inode); + u64 page_start; + u64 page_end; + u64 page_cnt; + u64 start = (u64)start_index << PAGE_SHIFT; + int ret; + int i; + int i_done; + struct btrfs_ordered_extent *ordered; + struct extent_state *cached_state = NULL; + struct extent_io_tree *tree; + struct extent_changeset *data_reserved = NULL; + gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); + + file_end = (isize - 1) >> PAGE_SHIFT; + if (!isize || start_index > file_end) + return 0; + + page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1); + + ret = btrfs_delalloc_reserve_space(inode, &data_reserved, + start, page_cnt << PAGE_SHIFT); + if (ret) + return ret; + i_done = 0; + tree = &BTRFS_I(inode)->io_tree; + + /* step one, lock all the pages */ + for (i = 0; i < page_cnt; i++) { + struct page *page; +again: + page = find_or_create_page(inode->i_mapping, + start_index + i, mask); + if (!page) + break; + + page_start = page_offset(page); + page_end = page_start + PAGE_SIZE - 1; + while (1) { + lock_extent_bits(tree, page_start, page_end, + &cached_state); + ordered = btrfs_lookup_ordered_extent(inode, + page_start); + unlock_extent_cached(tree, page_start, page_end, + &cached_state); + if (!ordered) + break; + + unlock_page(page); + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + lock_page(page); + /* + * we unlocked the page above, so we need check if + * it was released or not. + */ + if (page->mapping != inode->i_mapping) { + unlock_page(page); + put_page(page); + goto again; + } + } + + if (!PageUptodate(page)) { + btrfs_readpage(NULL, page); + lock_page(page); + if (!PageUptodate(page)) { + unlock_page(page); + put_page(page); + ret = -EIO; + break; + } + } + + if (page->mapping != inode->i_mapping) { + unlock_page(page); + put_page(page); + goto again; + } + + pages[i] = page; + i_done++; + } + if (!i_done || ret) + goto out; + + if (!(inode->i_sb->s_flags & SB_ACTIVE)) + goto out; + + /* + * so now we have a nice long stream of locked + * and up to date pages, lets wait on them + */ + for (i = 0; i < i_done; i++) + wait_on_page_writeback(pages[i]); + + page_start = page_offset(pages[0]); + page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE; + + lock_extent_bits(&BTRFS_I(inode)->io_tree, + page_start, page_end - 1, &cached_state); + clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start, + page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC | + EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, + &cached_state); + + if (i_done != page_cnt) { + spin_lock(&BTRFS_I(inode)->lock); + btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); + spin_unlock(&BTRFS_I(inode)->lock); + btrfs_delalloc_release_space(inode, data_reserved, + start, (page_cnt - i_done) << PAGE_SHIFT, true); + } + + + set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1, + &cached_state); + + unlock_extent_cached(&BTRFS_I(inode)->io_tree, + page_start, page_end - 1, &cached_state); + + for (i = 0; i < i_done; i++) { + clear_page_dirty_for_io(pages[i]); + ClearPageChecked(pages[i]); + set_page_extent_mapped(pages[i]); + set_page_dirty(pages[i]); + unlock_page(pages[i]); + put_page(pages[i]); + } + btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT); + extent_changeset_free(data_reserved); + return i_done; +out: + for (i = 0; i < i_done; i++) { + unlock_page(pages[i]); + put_page(pages[i]); + } + btrfs_delalloc_release_space(inode, data_reserved, + start, page_cnt << PAGE_SHIFT, true); + btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT); + extent_changeset_free(data_reserved); + return ret; + +} + +int btrfs_defrag_file(struct inode *inode, struct file *file, + struct btrfs_ioctl_defrag_range_args *range, + u64 newer_than, unsigned long max_to_defrag) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct file_ra_state *ra = NULL; + unsigned long last_index; + u64 isize = i_size_read(inode); + u64 last_len = 0; + u64 skip = 0; + u64 defrag_end = 0; + u64 newer_off = range->start; + unsigned long i; + unsigned long ra_index = 0; + int ret; + int defrag_count = 0; + int compress_type = BTRFS_COMPRESS_ZLIB; + u32 extent_thresh = range->extent_thresh; + unsigned long max_cluster = SZ_256K >> PAGE_SHIFT; + unsigned long cluster = max_cluster; + u64 new_align = ~((u64)SZ_128K - 1); + struct page **pages = NULL; + bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS; + + if (isize == 0) + return 0; + + if (range->start >= isize) + return -EINVAL; + + if (do_compress) { + if (range->compress_type > BTRFS_COMPRESS_TYPES) + return -EINVAL; + if (range->compress_type) + compress_type = range->compress_type; + } + + if (extent_thresh == 0) + extent_thresh = SZ_256K; + + /* + * If we were not given a file, allocate a readahead context. As + * readahead is just an optimization, defrag will work without it so + * we don't error out. + */ + if (!file) { + ra = kzalloc(sizeof(*ra), GFP_KERNEL); + if (ra) + file_ra_state_init(ra, inode->i_mapping); + } else { + ra = &file->f_ra; + } + + pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL); + if (!pages) { + ret = -ENOMEM; + goto out_ra; + } + + /* find the last page to defrag */ + if (range->start + range->len > range->start) { + last_index = min_t(u64, isize - 1, + range->start + range->len - 1) >> PAGE_SHIFT; + } else { + last_index = (isize - 1) >> PAGE_SHIFT; + } + + if (newer_than) { + ret = find_new_extents(root, inode, newer_than, + &newer_off, SZ_64K); + if (!ret) { + range->start = newer_off; + /* + * we always align our defrag to help keep + * the extents in the file evenly spaced + */ + i = (newer_off & new_align) >> PAGE_SHIFT; + } else + goto out_ra; + } else { + i = range->start >> PAGE_SHIFT; + } + if (!max_to_defrag) + max_to_defrag = last_index - i + 1; + + /* + * make writeback starts from i, so the defrag range can be + * written sequentially. + */ + if (i < inode->i_mapping->writeback_index) + inode->i_mapping->writeback_index = i; + + while (i <= last_index && defrag_count < max_to_defrag && + (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) { + /* + * make sure we stop running if someone unmounts + * the FS + */ + if (!(inode->i_sb->s_flags & SB_ACTIVE)) + break; + + if (btrfs_defrag_cancelled(fs_info)) { + btrfs_debug(fs_info, "defrag_file cancelled"); + ret = -EAGAIN; + break; + } + + if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT, + extent_thresh, &last_len, &skip, + &defrag_end, do_compress)){ + unsigned long next; + /* + * the should_defrag function tells us how much to skip + * bump our counter by the suggested amount + */ + next = DIV_ROUND_UP(skip, PAGE_SIZE); + i = max(i + 1, next); + continue; + } + + if (!newer_than) { + cluster = (PAGE_ALIGN(defrag_end) >> + PAGE_SHIFT) - i; + cluster = min(cluster, max_cluster); + } else { + cluster = max_cluster; + } + + if (i + cluster > ra_index) { + ra_index = max(i, ra_index); + if (ra) + page_cache_sync_readahead(inode->i_mapping, ra, + file, ra_index, cluster); + ra_index += cluster; + } + + inode_lock(inode); + if (do_compress) + BTRFS_I(inode)->defrag_compress = compress_type; + ret = cluster_pages_for_defrag(inode, pages, i, cluster); + if (ret < 0) { + inode_unlock(inode); + goto out_ra; + } + + defrag_count += ret; + balance_dirty_pages_ratelimited(inode->i_mapping); + inode_unlock(inode); + + if (newer_than) { + if (newer_off == (u64)-1) + break; + + if (ret > 0) + i += ret; + + newer_off = max(newer_off + 1, + (u64)i << PAGE_SHIFT); + + ret = find_new_extents(root, inode, newer_than, + &newer_off, SZ_64K); + if (!ret) { + range->start = newer_off; + i = (newer_off & new_align) >> PAGE_SHIFT; + } else { + break; + } + } else { + if (ret > 0) { + i += ret; + last_len += ret << PAGE_SHIFT; + } else { + i++; + last_len = 0; + } + } + } + + if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) { + filemap_flush(inode->i_mapping); + if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, + &BTRFS_I(inode)->runtime_flags)) + filemap_flush(inode->i_mapping); + } + + if (range->compress_type == BTRFS_COMPRESS_LZO) { + btrfs_set_fs_incompat(fs_info, COMPRESS_LZO); + } else if (range->compress_type == BTRFS_COMPRESS_ZSTD) { + btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD); + } + + ret = defrag_count; + +out_ra: + if (do_compress) { + inode_lock(inode); + BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE; + inode_unlock(inode); + } + if (!file) + kfree(ra); + kfree(pages); + return ret; +} + +static noinline int btrfs_ioctl_resize(struct file *file, + void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + u64 new_size; + u64 old_size; + u64 devid = 1; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_ioctl_vol_args *vol_args; + struct btrfs_trans_handle *trans; + struct btrfs_device *device = NULL; + char *sizestr; + char *retptr; + char *devstr = NULL; + int ret = 0; + int mod = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + mnt_drop_write_file(file); + return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + } + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto out; + } + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + + sizestr = vol_args->name; + devstr = strchr(sizestr, ':'); + if (devstr) { + sizestr = devstr + 1; + *devstr = '\0'; + devstr = vol_args->name; + ret = kstrtoull(devstr, 10, &devid); + if (ret) + goto out_free; + if (!devid) { + ret = -EINVAL; + goto out_free; + } + btrfs_info(fs_info, "resizing devid %llu", devid); + } + + device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true); + if (!device) { + btrfs_info(fs_info, "resizer unable to find device %llu", + devid); + ret = -ENODEV; + goto out_free; + } + + 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_free; + } + + if (!strcmp(sizestr, "max")) + new_size = device->bdev->bd_inode->i_size; + else { + 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_free; + } + } + + if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { + ret = -EPERM; + goto out_free; + } + + old_size = btrfs_device_get_total_bytes(device); + + if (mod < 0) { + if (new_size > old_size) { + ret = -EINVAL; + goto out_free; + } + new_size = old_size - new_size; + } else if (mod > 0) { + if (new_size > ULLONG_MAX - old_size) { + ret = -ERANGE; + goto out_free; + } + new_size = old_size + new_size; + } + + if (new_size < SZ_256M) { + ret = -EINVAL; + goto out_free; + } + if (new_size > device->bdev->bd_inode->i_size) { + ret = -EFBIG; + goto out_free; + } + + new_size = round_down(new_size, fs_info->sectorsize); + + btrfs_info_in_rcu(fs_info, "new size for %s is %llu", + rcu_str_deref(device->name), new_size); + + if (new_size > old_size) { + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_free; + } + 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 */ + +out_free: + kfree(vol_args); +out: + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); + mnt_drop_write_file(file); + return ret; +} + +static noinline int btrfs_ioctl_snap_create_transid(struct file *file, + const char *name, unsigned long fd, int subvol, + u64 *transid, bool readonly, + struct btrfs_qgroup_inherit *inherit) +{ + int namelen; + int ret = 0; + + if (!S_ISDIR(file_inode(file)->i_mode)) + return -ENOTDIR; + + ret = mnt_want_write_file(file); + if (ret) + goto out; + + namelen = strlen(name); + if (strchr(name, '/')) { + ret = -EINVAL; + goto out_drop_write; + } + + if (name[0] == '.' && + (namelen == 1 || (name[1] == '.' && namelen == 2))) { + ret = -EEXIST; + goto out_drop_write; + } + + if (subvol) { + ret = btrfs_mksubvol(&file->f_path, name, namelen, + NULL, transid, readonly, inherit); + } else { + struct fd src = fdget(fd); + struct inode *src_inode; + if (!src.file) { + ret = -EINVAL; + goto out_drop_write; + } + + src_inode = file_inode(src.file); + 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(src_inode)) { + /* + * Subvolume creation is not restricted, but snapshots + * are limited to own subvolumes only + */ + ret = -EPERM; + } else { + ret = btrfs_mksubvol(&file->f_path, name, namelen, + BTRFS_I(src_inode)->root, + transid, readonly, inherit); + } + fdput(src); + } +out_drop_write: + mnt_drop_write_file(file); +out: + return ret; +} + +static noinline int btrfs_ioctl_snap_create(struct file *file, + void __user *arg, int subvol) +{ + struct btrfs_ioctl_vol_args *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); + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + + ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, + vol_args->fd, subvol, + NULL, false, NULL); + + kfree(vol_args); + return ret; +} + +static noinline int btrfs_ioctl_snap_create_v2(struct file *file, + void __user *arg, int subvol) +{ + struct btrfs_ioctl_vol_args_v2 *vol_args; + int ret; + u64 transid = 0; + u64 *ptr = NULL; + bool readonly = false; + struct btrfs_qgroup_inherit *inherit = NULL; + + 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); + vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; + + if (vol_args->flags & + ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY | + BTRFS_SUBVOL_QGROUP_INHERIT)) { + ret = -EOPNOTSUPP; + goto free_args; + } + + if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC) + ptr = &transid; + if (vol_args->flags & BTRFS_SUBVOL_RDONLY) + readonly = true; + if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { + u64 nums; + + if (vol_args->size < sizeof(*inherit) || + vol_args->size > PAGE_SIZE) { + ret = -EINVAL; + goto free_args; + } + inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size); + if (IS_ERR(inherit)) { + ret = PTR_ERR(inherit); + goto free_args; + } + + if (inherit->num_qgroups > PAGE_SIZE || + inherit->num_ref_copies > PAGE_SIZE || + inherit->num_excl_copies > PAGE_SIZE) { + ret = -EINVAL; + goto free_inherit; + } + + nums = inherit->num_qgroups + 2 * inherit->num_ref_copies + + 2 * inherit->num_excl_copies; + if (vol_args->size != struct_size(inherit, qgroups, nums)) { + ret = -EINVAL; + goto free_inherit; + } + } + + ret = btrfs_ioctl_snap_create_transid(file, vol_args->name, + vol_args->fd, subvol, ptr, + readonly, inherit); + if (ret) + goto free_inherit; + + if (ptr && copy_to_user(arg + + offsetof(struct btrfs_ioctl_vol_args_v2, + transid), + ptr, sizeof(*ptr))) + ret = -EFAULT; + +free_inherit: + kfree(inherit); +free_args: + kfree(vol_args); + return ret; +} + +static noinline int btrfs_ioctl_subvol_getflags(struct file *file, + void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + int ret = 0; + u64 flags = 0; + + if (btrfs_ino(BTRFS_I(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 = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_trans_handle *trans; + u64 root_flags; + u64 flags; + int ret = 0; + + if (!inode_owner_or_capable(inode)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + goto out; + + 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_CREATE_ASYNC) { + ret = -EINVAL; + 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", + root->root_key.objectid); + 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); +out: + return ret; +} + +static noinline int key_in_sk(struct btrfs_key *key, + 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 0; + + 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 0; + return 1; +} + +static noinline int copy_to_sk(struct btrfs_path *path, + struct btrfs_key *key, + struct btrfs_ioctl_search_key *sk, + size_t *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_nr(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) { + ret = 1; + goto out; + } + + /* + * 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) { + ret = 1; + goto out; + } + + sh.objectid = key->objectid; + sh.offset = key->offset; + sh.type = key->type; + 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 (probe_user_write(ubuf + *sk_offset, &sh, sizeof(sh))) { + ret = 0; + goto out; + } + + *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)) { + ret = 0; + *sk_offset -= sizeof(sh); + goto out; + } + + *sk_offset += item_len; + } + (*num_found)++; + + if (ret) /* -EOVERFLOW from above */ + goto out; + + if (*num_found >= sk->nr_items) { + ret = 1; + goto out; + } + } +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; +out: + /* + * 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 inode *inode, + struct btrfs_ioctl_search_key *sk, + size_t *buf_size, + char __user *ubuf) +{ + struct btrfs_fs_info *info = btrfs_sb(inode->i_sb); + struct btrfs_root *root; + struct btrfs_key key; + struct btrfs_path *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 of the inode that was passed */ + root = BTRFS_I(inode)->root; + } else { + key.objectid = sk->tree_id; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(info, &key); + if (IS_ERR(root)) { + btrfs_free_path(path); + return PTR_ERR(root); + } + } + + key.objectid = sk->min_objectid; + key.type = sk->min_type; + key.offset = sk->min_offset; + + while (1) { + ret = fault_in_pages_writeable(ubuf + sk_offset, + *buf_size - sk_offset); + if (ret) + break; + + ret = btrfs_search_forward(root, &key, path, sk->min_transid); + if (ret != 0) { + if (ret > 0) + ret = 0; + goto err; + } + ret = copy_to_sk(path, &key, sk, buf_size, ubuf, + &sk_offset, &num_found); + btrfs_release_path(path); + if (ret) + break; + + } + if (ret > 0) + ret = 0; +err: + sk->nr_items = num_found; + btrfs_free_path(path); + return ret; +} + +static noinline int btrfs_ioctl_tree_search(struct file *file, + void __user *argp) +{ + struct btrfs_ioctl_search_args __user *uargs; + struct btrfs_ioctl_search_key sk; + struct inode *inode; + int ret; + size_t buf_size; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + uargs = (struct btrfs_ioctl_search_args __user *)argp; + + if (copy_from_user(&sk, &uargs->key, sizeof(sk))) + return -EFAULT; + + buf_size = sizeof(uargs->buf); + + inode = file_inode(file); + ret = search_ioctl(inode, &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 file *file, + void __user *argp) +{ + struct btrfs_ioctl_search_args_v2 __user *uarg; + struct btrfs_ioctl_search_args_v2 args; + struct inode *inode; + int ret; + size_t buf_size; + const size_t buf_limit = SZ_16M; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* copy search header and buffer size */ + uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp; + 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; + + inode = file_inode(file); + ret = search_ioctl(inode, &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 INODE_REFs to identify path name of 'dirid' directory + * in a 'tree_id' tree. and sets path name to 'name'. + */ +static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info, + u64 tree_id, u64 dirid, char *name) +{ + struct btrfs_root *root; + 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; + struct btrfs_path *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 = tree_id; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(info, &key); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + + key.objectid = dirid; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + + while (1) { + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto out; + else if (ret > 0) { + ret = btrfs_previous_item(root, path, dirid, + BTRFS_INODE_REF_KEY); + if (ret < 0) + goto out; + else if (ret > 0) { + ret = -ENOENT; + goto out; + } + } + + l = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(l, &key, slot); + + 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) { + ret = -ENAMETOOLONG; + goto out; + } + + *(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'; + ret = 0; +out: + btrfs_free_path(path); + return ret; +} + +static int btrfs_search_path_in_tree_user(struct inode *inode, + struct btrfs_ioctl_ino_lookup_user_args *args) +{ + struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; + struct super_block *sb = inode->i_sb; + struct btrfs_key upper_limit = BTRFS_I(inode)->location; + u64 treeid = BTRFS_I(inode)->root->root_key.objectid; + 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; + struct btrfs_path *path; + struct btrfs_key key, key2; + struct extent_buffer *leaf; + struct inode *temp_inode; + 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.objectid) { + ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1]; + + key.objectid = treeid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + + key.objectid = dirid; + key.type = BTRFS_INODE_REF_KEY; + key.offset = (u64)-1; + while (1) { + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + goto out; + } else if (ret > 0) { + ret = btrfs_previous_item(root, path, dirid, + BTRFS_INODE_REF_KEY); + if (ret < 0) { + goto out; + } else if (ret > 0) { + ret = -ENOENT; + goto out; + } + } + + leaf = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(leaf, &key, slot); + + 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; + } + + *(ptr + len) = '/'; + read_extent_buffer(leaf, ptr, + (unsigned long)(iref + 1), len); + + /* Check the read+exec permission of this directory */ + ret = btrfs_previous_item(root, path, dirid, + BTRFS_INODE_ITEM_KEY); + if (ret < 0) { + goto out; + } else if (ret > 0) { + ret = -ENOENT; + goto out; + } + + leaf = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(leaf, &key2, slot); + if (key2.objectid != dirid) { + ret = -ENOENT; + goto out; + } + + temp_inode = btrfs_iget(sb, &key2, root, NULL); + if (IS_ERR(temp_inode)) { + ret = PTR_ERR(temp_inode); + goto out; + } + ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC); + iput(temp_inode); + if (ret) { + ret = -EACCES; + goto out; + } + + if (key.offset == upper_limit.objectid) + break; + if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { + ret = -EACCES; + goto out; + } + + btrfs_release_path(path); + key.objectid = key.offset; + key.offset = (u64)-1; + dirid = key.objectid; + } + + memmove(args->path, ptr, total_len); + args->path[total_len] = '\0'; + btrfs_release_path(path); + } + + /* Get the bottom subvolume's name from ROOT_REF */ + root = fs_info->tree_root; + key.objectid = treeid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = args->treeid; + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + goto out; + } else if (ret > 0) { + ret = -ENOENT; + goto out; + } + + 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_nr(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)) { + ret = -EINVAL; + goto out; + } + + /* 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: + btrfs_free_path(path); + return ret; +} + +static noinline int btrfs_ioctl_ino_lookup(struct file *file, + void __user *argp) +{ + struct btrfs_ioctl_ino_lookup_args *args; + struct inode *inode; + int ret = 0; + + args = memdup_user(argp, sizeof(*args)); + if (IS_ERR(args)) + return PTR_ERR(args); + + inode = file_inode(file); + + /* + * 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_I(inode)->root->root_key.objectid; + + if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) { + args->name[0] = 0; + goto out; + } + + if (!capable(CAP_SYS_ADMIN)) { + ret = -EPERM; + goto out; + } + + ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info, + args->treeid, args->objectid, + args->name); + +out: + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + ret = -EFAULT; + + kfree(args); + 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 *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_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) { + /* + * The subvolume does not exist under fd with which this is + * called + */ + kfree(args); + return -EACCES; + } + + ret = btrfs_search_path_in_tree_user(inode, args); + + if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) + ret = -EFAULT; + + kfree(args); + return ret; +} + +/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */ +static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp) +{ + 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; + unsigned long item_len; + struct inode *inode; + int slot; + int ret = 0; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL); + if (!subvol_info) { + btrfs_free_path(path); + return -ENOMEM; + } + + inode = file_inode(file); + fs_info = BTRFS_I(inode)->root->fs_info; + + /* Get root_item of inode's subvolume */ + key.objectid = BTRFS_I(inode)->root->root_key.objectid; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + 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 */ + root = fs_info->tree_root; + + key.type = BTRFS_ROOT_BACKREF_KEY; + key.offset = 0; + 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 (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) { + subvol_info->parent_id = key.offset; + + rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref); + subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref); + + item_off = btrfs_item_ptr_offset(leaf, slot) + + sizeof(struct btrfs_root_ref); + item_len = btrfs_item_size_nr(leaf, slot) + - sizeof(struct btrfs_root_ref); + read_extent_buffer(leaf, subvol_info->name, + item_off, item_len); + } else { + ret = -ENOENT; + goto out; + } + } + + if (copy_to_user(argp, subvol_info, sizeof(*subvol_info))) + ret = -EFAULT; + +out: + btrfs_free_path(path); + kzfree(subvol_info); + return ret; +} + +/* + * Return ROOT_REF information of the subvolume containing this inode + * except the subvolume name. + */ +static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp) +{ + struct btrfs_ioctl_get_subvol_rootref_args *rootrefs; + struct btrfs_root_ref *rref; + struct btrfs_root *root; + struct btrfs_path *path; + struct btrfs_key key; + struct extent_buffer *leaf; + struct inode *inode; + 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); + } + + inode = file_inode(file); + root = BTRFS_I(inode)->root->fs_info->tree_root; + objectid = BTRFS_I(inode)->root->root_key.objectid; + + key.objectid = objectid; + key.type = BTRFS_ROOT_REF_KEY; + key.offset = rootrefs->min_treeid; + found = 0; + + 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 (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 (ret > 0) { + ret = -EUCLEAN; + goto out; + } + } + +out: + 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; + } + + kfree(rootrefs); + btrfs_free_path(path); + + return ret; +} + +static noinline int btrfs_ioctl_snap_destroy(struct file *file, + void __user *arg) +{ + struct dentry *parent = file->f_path.dentry; + struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb); + struct dentry *dentry; + struct inode *dir = d_inode(parent); + struct inode *inode; + struct btrfs_root *root = BTRFS_I(dir)->root; + struct btrfs_root *dest = NULL; + struct btrfs_ioctl_vol_args *vol_args; + int namelen; + int err = 0; + + if (!S_ISDIR(dir->i_mode)) + return -ENOTDIR; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) + return PTR_ERR(vol_args); + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + namelen = strlen(vol_args->name); + if (strchr(vol_args->name, '/') || + strncmp(vol_args->name, "..", namelen) == 0) { + err = -EINVAL; + goto out; + } + + err = mnt_want_write_file(file); + if (err) + goto out; + + + err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); + if (err == -EINTR) + goto out_drop_write; + dentry = lookup_one_len(vol_args->name, parent, namelen); + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto out_unlock_dir; + } + + if (d_really_is_negative(dentry)) { + err = -ENOENT; + goto out_dput; + } + + 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). + */ + err = -EPERM; + if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED)) + goto out_dput; + + /* + * 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. + */ + err = -EINVAL; + if (root == dest) + goto out_dput; + + err = inode_permission(inode, MAY_WRITE | MAY_EXEC); + if (err) + goto out_dput; + } + + /* check if subvolume may be deleted by a user */ + err = btrfs_may_delete(dir, dentry, 1); + if (err) + goto out_dput; + + if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { + err = -EINVAL; + goto out_dput; + } + + inode_lock(inode); + err = btrfs_delete_subvolume(dir, dentry); + inode_unlock(inode); + if (!err) + d_delete(dentry); + +out_dput: + dput(dentry); +out_unlock_dir: + inode_unlock(dir); +out_drop_write: + mnt_drop_write_file(file); +out: + kfree(vol_args); + return err; +} + +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; + 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(inode, MAY_WRITE)) { + ret = -EPERM; + goto out; + } + + range = kzalloc(sizeof(*range), GFP_KERNEL); + if (!range) { + ret = -ENOMEM; + goto out; + } + + if (argp) { + if (copy_from_user(range, argp, + sizeof(*range))) { + ret = -EFAULT; + kfree(range); + goto out; + } + /* compression requires us to start the IO */ + if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) { + 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(file_inode(file), file, + range, BTRFS_OLDEST_GENERATION, 0); + if (ret > 0) + ret = 0; + kfree(range); + 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 *vol_args; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) + return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto out; + } + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + ret = btrfs_init_new_device(fs_info, vol_args->name); + + if (!ret) + btrfs_info(fs_info, "disk added %s", vol_args->name); + + kfree(vol_args); +out: + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); + return ret; +} + +static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_ioctl_vol_args_v2 *vol_args; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto err_drop; + } + + /* Check for compatibility reject unknown flags */ + if (vol_args->flags & ~BTRFS_VOL_ARG_V2_FLAGS_SUPPORTED) { + ret = -EOPNOTSUPP; + goto out; + } + + if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + goto out; + } + + if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) { + ret = btrfs_rm_device(fs_info, NULL, vol_args->devid); + } else { + vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0'; + ret = btrfs_rm_device(fs_info, vol_args->name, 0); + } + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); + + 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); + } +out: + kfree(vol_args); +err_drop: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_ioctl_vol_args *vol_args; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + goto out_drop_write; + } + + vol_args = memdup_user(arg, sizeof(*vol_args)); + if (IS_ERR(vol_args)) { + ret = PTR_ERR(vol_args); + goto out; + } + + vol_args->name[BTRFS_PATH_NAME_MAX] = '\0'; + ret = btrfs_rm_device(fs_info, vol_args->name, 0); + + if (!ret) + btrfs_info(fs_info, "disk deleted %s", vol_args->name); + kfree(vol_args); +out: + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); +out_drop_write: + mnt_drop_write_file(file); + + return ret; +} + +static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_fs_info_args *fi_args; + struct btrfs_device *device; + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + int ret = 0; + + fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL); + if (!fi_args) + return -ENOMEM; + + 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_info->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 (copy_to_user(arg, fi_args, sizeof(*fi_args))) + ret = -EFAULT; + + kfree(fi_args); + return ret; +} + +static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_dev_info_args *di_args; + struct btrfs_device *dev; + int ret = 0; + char *s_uuid = NULL; + + di_args = memdup_user(arg, sizeof(*di_args)); + if (IS_ERR(di_args)) + return PTR_ERR(di_args); + + if (!btrfs_is_empty_uuid(di_args->uuid)) + s_uuid = di_args->uuid; + + rcu_read_lock(); + dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid, + NULL, true); + + 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)); + if (dev->name) { + strncpy(di_args->path, rcu_str_deref(dev->name), + sizeof(di_args->path) - 1); + di_args->path[sizeof(di_args->path) - 1] = 0; + } else { + di_args->path[0] = '\0'; + } + +out: + rcu_read_unlock(); + if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) + ret = -EFAULT; + + kfree(di_args); + return ret; +} + +static struct page *extent_same_get_page(struct inode *inode, pgoff_t index) +{ + struct page *page; + + page = grab_cache_page(inode->i_mapping, index); + if (!page) + return ERR_PTR(-ENOMEM); + + if (!PageUptodate(page)) { + int ret; + + ret = btrfs_readpage(NULL, page); + if (ret) + return ERR_PTR(ret); + lock_page(page); + if (!PageUptodate(page)) { + unlock_page(page); + put_page(page); + return ERR_PTR(-EIO); + } + if (page->mapping != inode->i_mapping) { + unlock_page(page); + put_page(page); + return ERR_PTR(-EAGAIN); + } + } + + return page; +} + +static int gather_extent_pages(struct inode *inode, struct page **pages, + int num_pages, u64 off) +{ + int i; + pgoff_t index = off >> PAGE_SHIFT; + + for (i = 0; i < num_pages; i++) { +again: + pages[i] = extent_same_get_page(inode, index + i); + if (IS_ERR(pages[i])) { + int err = PTR_ERR(pages[i]); + + if (err == -EAGAIN) + goto again; + pages[i] = NULL; + return err; + } + } + return 0; +} + +static int lock_extent_range(struct inode *inode, u64 off, u64 len, + bool retry_range_locking) +{ + /* + * Do any pending delalloc/csum calculations on inode, one way or + * another, and lock file content. + * The locking order is: + * + * 1) pages + * 2) range in the inode's io tree + */ + while (1) { + struct btrfs_ordered_extent *ordered; + lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); + ordered = btrfs_lookup_first_ordered_extent(inode, + off + len - 1); + if ((!ordered || + ordered->file_offset + ordered->len <= off || + ordered->file_offset >= off + len) && + !test_range_bit(&BTRFS_I(inode)->io_tree, off, + off + len - 1, EXTENT_DELALLOC, 0, NULL)) { + if (ordered) + btrfs_put_ordered_extent(ordered); + break; + } + unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1); + if (ordered) + btrfs_put_ordered_extent(ordered); + if (!retry_range_locking) + return -EAGAIN; + btrfs_wait_ordered_range(inode, off, len); + } + return 0; +} + +static void btrfs_double_inode_unlock(struct inode *inode1, struct inode *inode2) +{ + inode_unlock(inode1); + inode_unlock(inode2); +} + +static void btrfs_double_inode_lock(struct inode *inode1, struct inode *inode2) +{ + if (inode1 < inode2) + swap(inode1, inode2); + + inode_lock_nested(inode1, I_MUTEX_PARENT); + inode_lock_nested(inode2, I_MUTEX_CHILD); +} + +static void btrfs_double_extent_unlock(struct inode *inode1, u64 loff1, + struct inode *inode2, u64 loff2, u64 len) +{ + unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1); + unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1); +} + +static int btrfs_double_extent_lock(struct inode *inode1, u64 loff1, + struct inode *inode2, u64 loff2, u64 len, + bool retry_range_locking) +{ + int ret; + + if (inode1 < inode2) { + swap(inode1, inode2); + swap(loff1, loff2); + } + ret = lock_extent_range(inode1, loff1, len, retry_range_locking); + if (ret) + return ret; + ret = lock_extent_range(inode2, loff2, len, retry_range_locking); + if (ret) + unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, + loff1 + len - 1); + return ret; +} + +struct cmp_pages { + int num_pages; + struct page **src_pages; + struct page **dst_pages; +}; + +static void btrfs_cmp_data_free(struct cmp_pages *cmp) +{ + int i; + struct page *pg; + + for (i = 0; i < cmp->num_pages; i++) { + pg = cmp->src_pages[i]; + if (pg) { + unlock_page(pg); + put_page(pg); + cmp->src_pages[i] = NULL; + } + pg = cmp->dst_pages[i]; + if (pg) { + unlock_page(pg); + put_page(pg); + cmp->dst_pages[i] = NULL; + } + } +} + +static int btrfs_cmp_data_prepare(struct inode *src, u64 loff, + struct inode *dst, u64 dst_loff, + u64 len, struct cmp_pages *cmp) +{ + int ret; + int num_pages = PAGE_ALIGN(len) >> PAGE_SHIFT; + + cmp->num_pages = num_pages; + + ret = gather_extent_pages(src, cmp->src_pages, num_pages, loff); + if (ret) + goto out; + + ret = gather_extent_pages(dst, cmp->dst_pages, num_pages, dst_loff); + +out: + if (ret) + btrfs_cmp_data_free(cmp); + return ret; +} + +static int btrfs_cmp_data(u64 len, struct cmp_pages *cmp) +{ + int ret = 0; + int i; + struct page *src_page, *dst_page; + unsigned int cmp_len = PAGE_SIZE; + void *addr, *dst_addr; + + i = 0; + while (len) { + if (len < PAGE_SIZE) + cmp_len = len; + + BUG_ON(i >= cmp->num_pages); + + src_page = cmp->src_pages[i]; + dst_page = cmp->dst_pages[i]; + ASSERT(PageLocked(src_page)); + ASSERT(PageLocked(dst_page)); + + addr = kmap_atomic(src_page); + dst_addr = kmap_atomic(dst_page); + + flush_dcache_page(src_page); + flush_dcache_page(dst_page); + + if (memcmp(addr, dst_addr, cmp_len)) + ret = -EBADE; + + kunmap_atomic(addr); + kunmap_atomic(dst_addr); + + if (ret) + break; + + len -= cmp_len; + i++; + } + + return ret; +} + +static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen, + u64 olen) +{ + u64 len = *plen; + u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize; + + if (off + olen > inode->i_size || off + olen < off) + return -EINVAL; + + /* if we extend to eof, continue to block boundary */ + if (off + len == inode->i_size) + *plen = len = ALIGN(inode->i_size, bs) - off; + + /* Check that we are block aligned - btrfs_clone() requires this */ + if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs)) + return -EINVAL; + + return 0; +} + +static int btrfs_extent_same_range(struct inode *src, u64 loff, u64 olen, + struct inode *dst, u64 dst_loff, + struct cmp_pages *cmp) +{ + int ret; + u64 len = olen; + bool same_inode = (src == dst); + u64 same_lock_start = 0; + u64 same_lock_len = 0; + + ret = extent_same_check_offsets(src, loff, &len, olen); + if (ret) + return ret; + + ret = extent_same_check_offsets(dst, dst_loff, &len, olen); + if (ret) + return ret; + + if (same_inode) { + /* + * Single inode case wants the same checks, except we + * don't want our length pushed out past i_size as + * comparing that data range makes no sense. + * + * extent_same_check_offsets() will do this for an + * unaligned length at i_size, so catch it here and + * reject the request. + * + * This effectively means we require aligned extents + * for the single-inode case, whereas the other cases + * allow an unaligned length so long as it ends at + * i_size. + */ + if (len != olen) + return -EINVAL; + + /* Check for overlapping ranges */ + if (dst_loff + len > loff && dst_loff < loff + len) + return -EINVAL; + + same_lock_start = min_t(u64, loff, dst_loff); + same_lock_len = max_t(u64, loff, dst_loff) + len - same_lock_start; + } else { + /* + * If the source and destination inodes are different, the + * source's range end offset matches the source's i_size, that + * i_size is not a multiple of the sector size, and the + * destination range does not go past the destination's i_size, + * we must round down the length to the nearest sector size + * multiple. If we don't do this adjustment we end replacing + * with zeroes the bytes in the range that starts at the + * deduplication range's end offset and ends at the next sector + * size multiple. + */ + if (loff + olen == i_size_read(src) && + dst_loff + len < i_size_read(dst)) { + const u64 sz = BTRFS_I(src)->root->fs_info->sectorsize; + + len = round_down(i_size_read(src), sz) - loff; + if (len == 0) + return 0; + olen = len; + } + } + +again: + ret = btrfs_cmp_data_prepare(src, loff, dst, dst_loff, olen, cmp); + if (ret) + return ret; + + if (same_inode) + ret = lock_extent_range(src, same_lock_start, same_lock_len, + false); + else + ret = btrfs_double_extent_lock(src, loff, dst, dst_loff, len, + false); + /* + * If one of the inodes has dirty pages in the respective range or + * ordered extents, we need to flush dellaloc and wait for all ordered + * extents in the range. We must unlock the pages and the ranges in the + * io trees to avoid deadlocks when flushing delalloc (requires locking + * pages) and when waiting for ordered extents to complete (they require + * range locking). + */ + if (ret == -EAGAIN) { + /* + * Ranges in the io trees already unlocked. Now unlock all + * pages before waiting for all IO to complete. + */ + btrfs_cmp_data_free(cmp); + if (same_inode) { + btrfs_wait_ordered_range(src, same_lock_start, + same_lock_len); + } else { + btrfs_wait_ordered_range(src, loff, len); + btrfs_wait_ordered_range(dst, dst_loff, len); + } + goto again; + } + ASSERT(ret == 0); + if (WARN_ON(ret)) { + /* ranges in the io trees already unlocked */ + btrfs_cmp_data_free(cmp); + return ret; + } + + /* pass original length for comparison so we stay within i_size */ + ret = btrfs_cmp_data(olen, cmp); + if (ret == 0) + ret = btrfs_clone(src, dst, loff, olen, len, dst_loff, 1); + + if (same_inode) + unlock_extent(&BTRFS_I(src)->io_tree, same_lock_start, + same_lock_start + same_lock_len - 1); + else + btrfs_double_extent_unlock(src, loff, dst, dst_loff, len); + + btrfs_cmp_data_free(cmp); + + return ret; +} + +#define BTRFS_MAX_DEDUPE_LEN SZ_16M + +static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen, + struct inode *dst, u64 dst_loff) +{ + int ret; + struct cmp_pages cmp; + int num_pages = PAGE_ALIGN(BTRFS_MAX_DEDUPE_LEN) >> PAGE_SHIFT; + bool same_inode = (src == dst); + u64 i, tail_len, chunk_count; + + if (olen == 0) + return 0; + + if (same_inode) + inode_lock(src); + else + btrfs_double_inode_lock(src, dst); + + /* don't make the dst file partly checksummed */ + if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != + (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) { + ret = -EINVAL; + goto out_unlock; + } + + tail_len = olen % BTRFS_MAX_DEDUPE_LEN; + chunk_count = div_u64(olen, BTRFS_MAX_DEDUPE_LEN); + if (chunk_count == 0) + num_pages = PAGE_ALIGN(tail_len) >> PAGE_SHIFT; + + /* + * If deduping ranges in the same inode, locking rules make it + * mandatory to always lock pages in ascending order to avoid deadlocks + * with concurrent tasks (such as starting writeback/delalloc). + */ + if (same_inode && dst_loff < loff) + swap(loff, dst_loff); + + /* + * We must gather up all the pages before we initiate our extent + * locking. We use an array for the page pointers. Size of the array is + * bounded by len, which is in turn bounded by BTRFS_MAX_DEDUPE_LEN. + */ + cmp.src_pages = kvmalloc_array(num_pages, sizeof(struct page *), + GFP_KERNEL | __GFP_ZERO); + cmp.dst_pages = kvmalloc_array(num_pages, sizeof(struct page *), + GFP_KERNEL | __GFP_ZERO); + if (!cmp.src_pages || !cmp.dst_pages) { + ret = -ENOMEM; + goto out_free; + } + + for (i = 0; i < chunk_count; i++) { + ret = btrfs_extent_same_range(src, loff, BTRFS_MAX_DEDUPE_LEN, + dst, dst_loff, &cmp); + if (ret) + goto out_free; + + loff += BTRFS_MAX_DEDUPE_LEN; + dst_loff += BTRFS_MAX_DEDUPE_LEN; + } + + if (tail_len > 0) + ret = btrfs_extent_same_range(src, loff, tail_len, dst, + dst_loff, &cmp); + +out_free: + kvfree(cmp.src_pages); + kvfree(cmp.dst_pages); + +out_unlock: + if (same_inode) + inode_unlock(src); + else + btrfs_double_inode_unlock(src, dst); + + return ret; +} + +int btrfs_dedupe_file_range(struct file *src_file, loff_t src_loff, + struct file *dst_file, loff_t dst_loff, + u64 olen) +{ + struct inode *src = file_inode(src_file); + struct inode *dst = file_inode(dst_file); + u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize; + + if (WARN_ON_ONCE(bs < PAGE_SIZE)) { + /* + * Btrfs does not support blocksize < page_size. As a + * result, btrfs_cmp_data() won't correctly handle + * this situation without an update. + */ + return -EINVAL; + } + + return btrfs_extent_same(src, src_loff, olen, dst, dst_loff); +} + +static int clone_finish_inode_update(struct btrfs_trans_handle *trans, + struct inode *inode, + u64 endoff, + const u64 destoff, + const u64 olen, + int no_time_update) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + int ret; + + inode_inc_iversion(inode); + if (!no_time_update) + inode->i_mtime = inode->i_ctime = current_time(inode); + /* + * We round up to the block size at eof when determining which + * extents to clone above, but shouldn't round up the file size. + */ + if (endoff > destoff + olen) + endoff = destoff + olen; + if (endoff > inode->i_size) + btrfs_i_size_write(BTRFS_I(inode), endoff); + + ret = btrfs_update_inode(trans, root, inode); + if (ret) { + btrfs_abort_transaction(trans, ret); + btrfs_end_transaction(trans); + goto out; + } + ret = btrfs_end_transaction(trans); +out: + return ret; +} + +static void clone_update_extent_map(struct btrfs_inode *inode, + const struct btrfs_trans_handle *trans, + const struct btrfs_path *path, + const u64 hole_offset, + const u64 hole_len) +{ + struct extent_map_tree *em_tree = &inode->extent_tree; + struct extent_map *em; + int ret; + + em = alloc_extent_map(); + if (!em) { + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); + return; + } + + if (path) { + struct btrfs_file_extent_item *fi; + + fi = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_file_extent_item); + btrfs_extent_item_to_extent_map(inode, path, fi, false, em); + em->generation = -1; + if (btrfs_file_extent_type(path->nodes[0], fi) == + BTRFS_FILE_EXTENT_INLINE) + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &inode->runtime_flags); + } else { + em->start = hole_offset; + em->len = hole_len; + em->ram_bytes = em->len; + em->orig_start = hole_offset; + em->block_start = EXTENT_MAP_HOLE; + em->block_len = 0; + em->orig_block_len = 0; + em->compress_type = BTRFS_COMPRESS_NONE; + em->generation = trans->transid; + } + + while (1) { + write_lock(&em_tree->lock); + ret = add_extent_mapping(em_tree, em, 1); + write_unlock(&em_tree->lock); + if (ret != -EEXIST) { + free_extent_map(em); + break; + } + btrfs_drop_extent_cache(inode, em->start, + em->start + em->len - 1, 0); + } + + if (ret) + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); +} + +/* + * Make sure we do not end up inserting an inline extent into a file that has + * already other (non-inline) extents. If a file has an inline extent it can + * not have any other extents and the (single) inline extent must start at the + * file offset 0. Failing to respect these rules will lead to file corruption, + * resulting in EIO errors on read/write operations, hitting BUG_ON's in mm, etc + * + * We can have extents that have been already written to disk or we can have + * dirty ranges still in delalloc, in which case the extent maps and items are + * created only when we run delalloc, and the delalloc ranges might fall outside + * the range we are currently locking in the inode's io tree. So we check the + * inode's i_size because of that (i_size updates are done while holding the + * i_mutex, which we are holding here). + * We also check to see if the inode has a size not greater than "datal" but has + * extents beyond it, due to an fallocate with FALLOC_FL_KEEP_SIZE (and we are + * protected against such concurrent fallocate calls by the i_mutex). + * + * If the file has no extents but a size greater than datal, do not allow the + * copy because we would need turn the inline extent into a non-inline one (even + * with NO_HOLES enabled). If we find our destination inode only has one inline + * extent, just overwrite it with the source inline extent if its size is less + * than the source extent's size, or we could copy the source inline extent's + * data into the destination inode's inline extent if the later is greater then + * the former. + */ +static int clone_copy_inline_extent(struct inode *dst, + struct btrfs_trans_handle *trans, + struct btrfs_path *path, + struct btrfs_key *new_key, + const u64 drop_start, + const u64 datal, + const u64 skip, + const u64 size, + char *inline_data) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(dst->i_sb); + struct btrfs_root *root = BTRFS_I(dst)->root; + const u64 aligned_end = ALIGN(new_key->offset + datal, + fs_info->sectorsize); + int ret; + struct btrfs_key key; + + if (new_key->offset > 0) + return -EOPNOTSUPP; + + key.objectid = btrfs_ino(BTRFS_I(dst)); + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = 0; + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) { + return ret; + } else if (ret > 0) { + if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + return ret; + else if (ret > 0) + goto copy_inline_extent; + } + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.objectid == btrfs_ino(BTRFS_I(dst)) && + key.type == BTRFS_EXTENT_DATA_KEY) { + ASSERT(key.offset > 0); + return -EOPNOTSUPP; + } + } else if (i_size_read(dst) <= datal) { + struct btrfs_file_extent_item *ei; + u64 ext_len; + + /* + * If the file size is <= datal, make sure there are no other + * extents following (can happen do to an fallocate call with + * the flag FALLOC_FL_KEEP_SIZE). + */ + ei = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_file_extent_item); + /* + * If it's an inline extent, it can not have other extents + * following it. + */ + if (btrfs_file_extent_type(path->nodes[0], ei) == + BTRFS_FILE_EXTENT_INLINE) + goto copy_inline_extent; + + ext_len = btrfs_file_extent_num_bytes(path->nodes[0], ei); + if (ext_len > aligned_end) + return -EOPNOTSUPP; + + ret = btrfs_next_item(root, path); + if (ret < 0) { + return ret; + } else if (ret == 0) { + btrfs_item_key_to_cpu(path->nodes[0], &key, + path->slots[0]); + if (key.objectid == btrfs_ino(BTRFS_I(dst)) && + key.type == BTRFS_EXTENT_DATA_KEY) + return -EOPNOTSUPP; + } + } + +copy_inline_extent: + /* + * We have no extent items, or we have an extent at offset 0 which may + * or may not be inlined. All these cases are dealt the same way. + */ + if (i_size_read(dst) > datal) { + /* + * If the destination inode has an inline extent... + * This would require copying the data from the source inline + * extent into the beginning of the destination's inline extent. + * But this is really complex, both extents can be compressed + * or just one of them, which would require decompressing and + * re-compressing data (which could increase the new compressed + * size, not allowing the compressed data to fit anymore in an + * inline extent). + * So just don't support this case for now (it should be rare, + * we are not really saving space when cloning inline extents). + */ + return -EOPNOTSUPP; + } + + btrfs_release_path(path); + ret = btrfs_drop_extents(trans, root, dst, drop_start, aligned_end, 1); + if (ret) + return ret; + ret = btrfs_insert_empty_item(trans, root, path, new_key, size); + if (ret) + return ret; + + if (skip) { + const u32 start = btrfs_file_extent_calc_inline_size(0); + + memmove(inline_data + start, inline_data + start + skip, datal); + } + + write_extent_buffer(path->nodes[0], inline_data, + btrfs_item_ptr_offset(path->nodes[0], + path->slots[0]), + size); + inode_add_bytes(dst, datal); + + return 0; +} + +/** + * btrfs_clone() - clone a range from inode file to another + * + * @src: Inode to clone from + * @inode: Inode to clone to + * @off: Offset within source to start clone from + * @olen: Original length, passed by user, of range to clone + * @olen_aligned: Block-aligned value of olen + * @destoff: Offset within @inode to start clone + * @no_time_update: Whether to update mtime/ctime on the target inode + */ +static int btrfs_clone(struct inode *src, struct inode *inode, + const u64 off, const u64 olen, const u64 olen_aligned, + const u64 destoff, int no_time_update) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_path *path = NULL; + struct extent_buffer *leaf; + struct btrfs_trans_handle *trans; + char *buf = NULL; + struct btrfs_key key; + u32 nritems; + int slot; + int ret; + const u64 len = olen_aligned; + u64 last_dest_end = destoff; + + ret = -ENOMEM; + buf = kvmalloc(fs_info->nodesize, GFP_KERNEL); + if (!buf) + return ret; + + path = btrfs_alloc_path(); + if (!path) { + kvfree(buf); + return ret; + } + + path->reada = READA_FORWARD; + /* clone data */ + key.objectid = btrfs_ino(BTRFS_I(src)); + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = off; + + while (1) { + u64 next_key_min_offset = key.offset + 1; + + /* + * note the key will change type as we walk through the + * tree. + */ + path->leave_spinning = 1; + ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path, + 0, 0); + if (ret < 0) + goto out; + /* + * First search, if no extent item that starts at offset off was + * found but the previous item is an extent item, it's possible + * it might overlap our target range, therefore process it. + */ + if (key.offset == off && ret > 0 && path->slots[0] > 0) { + btrfs_item_key_to_cpu(path->nodes[0], &key, + path->slots[0] - 1); + if (key.type == BTRFS_EXTENT_DATA_KEY) + path->slots[0]--; + } + + nritems = btrfs_header_nritems(path->nodes[0]); +process_slot: + if (path->slots[0] >= nritems) { + ret = btrfs_next_leaf(BTRFS_I(src)->root, path); + if (ret < 0) + goto out; + if (ret > 0) + break; + nritems = btrfs_header_nritems(path->nodes[0]); + } + leaf = path->nodes[0]; + slot = path->slots[0]; + + btrfs_item_key_to_cpu(leaf, &key, slot); + if (key.type > BTRFS_EXTENT_DATA_KEY || + key.objectid != btrfs_ino(BTRFS_I(src))) + break; + + if (key.type == BTRFS_EXTENT_DATA_KEY) { + struct btrfs_file_extent_item *extent; + int type; + u32 size; + struct btrfs_key new_key; + u64 disko = 0, diskl = 0; + u64 datao = 0, datal = 0; + u8 comp; + u64 drop_start; + + extent = btrfs_item_ptr(leaf, slot, + struct btrfs_file_extent_item); + comp = btrfs_file_extent_compression(leaf, extent); + type = btrfs_file_extent_type(leaf, extent); + if (type == BTRFS_FILE_EXTENT_REG || + type == BTRFS_FILE_EXTENT_PREALLOC) { + disko = btrfs_file_extent_disk_bytenr(leaf, + extent); + diskl = btrfs_file_extent_disk_num_bytes(leaf, + extent); + datao = btrfs_file_extent_offset(leaf, extent); + datal = btrfs_file_extent_num_bytes(leaf, + extent); + } else if (type == BTRFS_FILE_EXTENT_INLINE) { + /* take upper bound, may be compressed */ + datal = btrfs_file_extent_ram_bytes(leaf, + extent); + } + + /* + * The first search might have left us at an extent + * item that ends before our target range's start, can + * happen if we have holes and NO_HOLES feature enabled. + */ + if (key.offset + datal <= off) { + path->slots[0]++; + goto process_slot; + } else if (key.offset >= off + len) { + break; + } + next_key_min_offset = key.offset + datal; + size = btrfs_item_size_nr(leaf, slot); + read_extent_buffer(leaf, buf, + btrfs_item_ptr_offset(leaf, slot), + size); + + btrfs_release_path(path); + path->leave_spinning = 0; + + memcpy(&new_key, &key, sizeof(new_key)); + new_key.objectid = btrfs_ino(BTRFS_I(inode)); + if (off <= key.offset) + new_key.offset = key.offset + destoff - off; + else + new_key.offset = destoff; + + /* + * Deal with a hole that doesn't have an extent item + * that represents it (NO_HOLES feature enabled). + * This hole is either in the middle of the cloning + * range or at the beginning (fully overlaps it or + * partially overlaps it). + */ + if (new_key.offset != last_dest_end) + drop_start = last_dest_end; + else + drop_start = new_key.offset; + + /* + * 1 - adjusting old extent (we may have to split it) + * 1 - add new extent + * 1 - inode update + */ + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out; + } + + if (type == BTRFS_FILE_EXTENT_REG || + type == BTRFS_FILE_EXTENT_PREALLOC) { + /* + * a | --- range to clone ---| b + * | ------------- extent ------------- | + */ + + /* subtract range b */ + if (key.offset + datal > off + len) + datal = off + len - key.offset; + + /* subtract range a */ + if (off > key.offset) { + datao += off - key.offset; + datal -= off - key.offset; + } + + ret = btrfs_drop_extents(trans, root, inode, + drop_start, + new_key.offset + datal, + 1); + if (ret) { + if (ret != -EOPNOTSUPP) + btrfs_abort_transaction(trans, + ret); + btrfs_end_transaction(trans); + goto out; + } + + ret = btrfs_insert_empty_item(trans, root, path, + &new_key, size); + if (ret) { + btrfs_abort_transaction(trans, ret); + btrfs_end_transaction(trans); + goto out; + } + + leaf = path->nodes[0]; + slot = path->slots[0]; + write_extent_buffer(leaf, buf, + btrfs_item_ptr_offset(leaf, slot), + size); + + extent = btrfs_item_ptr(leaf, slot, + struct btrfs_file_extent_item); + + /* disko == 0 means it's a hole */ + if (!disko) + datao = 0; + + btrfs_set_file_extent_offset(leaf, extent, + datao); + btrfs_set_file_extent_num_bytes(leaf, extent, + datal); + + if (disko) { + inode_add_bytes(inode, datal); + ret = btrfs_inc_extent_ref(trans, + root, + disko, diskl, 0, + root->root_key.objectid, + btrfs_ino(BTRFS_I(inode)), + new_key.offset - datao); + if (ret) { + btrfs_abort_transaction(trans, + ret); + btrfs_end_transaction(trans); + goto out; + + } + } + } else if (type == BTRFS_FILE_EXTENT_INLINE) { + u64 skip = 0; + u64 trim = 0; + + if (off > key.offset) { + skip = off - key.offset; + new_key.offset += skip; + } + + if (key.offset + datal > off + len) + trim = key.offset + datal - (off + len); + + if (comp && (skip || trim)) { + ret = -EINVAL; + btrfs_end_transaction(trans); + goto out; + } + size -= skip + trim; + datal -= skip + trim; + + ret = clone_copy_inline_extent(inode, + trans, path, + &new_key, + drop_start, + datal, + skip, size, buf); + if (ret) { + if (ret != -EOPNOTSUPP) + btrfs_abort_transaction(trans, + ret); + btrfs_end_transaction(trans); + goto out; + } + leaf = path->nodes[0]; + slot = path->slots[0]; + } + + /* If we have an implicit hole (NO_HOLES feature). */ + if (drop_start < new_key.offset) + clone_update_extent_map(BTRFS_I(inode), trans, + NULL, drop_start, + new_key.offset - drop_start); + + clone_update_extent_map(BTRFS_I(inode), trans, + path, 0, 0); + + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(path); + + last_dest_end = ALIGN(new_key.offset + datal, + fs_info->sectorsize); + ret = clone_finish_inode_update(trans, inode, + last_dest_end, + destoff, olen, + no_time_update); + if (ret) + goto out; + if (new_key.offset + datal >= destoff + len) + break; + } + btrfs_release_path(path); + key.offset = next_key_min_offset; + + if (fatal_signal_pending(current)) { + ret = -EINTR; + goto out; + } + + cond_resched(); + } + ret = 0; + + if (last_dest_end < destoff + len) { + /* + * We have an implicit hole (NO_HOLES feature is enabled) that + * fully or partially overlaps our cloning range at its end. + */ + btrfs_release_path(path); + + /* + * 1 - remove extent(s) + * 1 - inode update + */ + trans = btrfs_start_transaction(root, 2); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out; + } + ret = btrfs_drop_extents(trans, root, inode, + last_dest_end, destoff + len, 1); + if (ret) { + if (ret != -EOPNOTSUPP) + btrfs_abort_transaction(trans, ret); + btrfs_end_transaction(trans); + goto out; + } + clone_update_extent_map(BTRFS_I(inode), trans, NULL, + last_dest_end, + destoff + len - last_dest_end); + ret = clone_finish_inode_update(trans, inode, destoff + len, + destoff, olen, no_time_update); + } + +out: + btrfs_free_path(path); + kvfree(buf); + return ret; +} + +static noinline int btrfs_clone_files(struct file *file, struct file *file_src, + u64 off, u64 olen, u64 destoff) +{ + struct inode *inode = file_inode(file); + struct inode *src = file_inode(file_src); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + int ret; + u64 len = olen; + u64 bs = fs_info->sb->s_blocksize; + int same_inode = src == inode; + + /* + * TODO: + * - split compressed inline extents. annoying: we need to + * decompress into destination's address_space (the file offset + * may change, so source mapping won't do), then recompress (or + * otherwise reinsert) a subrange. + * + * - split destination inode's inline extents. The inline extents can + * be either compressed or non-compressed. + */ + + if (btrfs_root_readonly(root)) + return -EROFS; + + if (file_src->f_path.mnt != file->f_path.mnt || + src->i_sb != inode->i_sb) + return -EXDEV; + + if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode)) + return -EISDIR; + + if (!same_inode) { + btrfs_double_inode_lock(src, inode); + } else { + inode_lock(src); + } + + /* don't make the dst file partly checksummed */ + if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) != + (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { + ret = -EINVAL; + goto out_unlock; + } + + /* determine range to clone */ + ret = -EINVAL; + if (off + len > src->i_size || off + len < off) + goto out_unlock; + if (len == 0) + olen = len = src->i_size - off; + /* + * If we extend to eof, continue to block boundary if and only if the + * destination end offset matches the destination file's size, otherwise + * we would be corrupting data by placing the eof block into the middle + * of a file. + */ + if (off + len == src->i_size) { + if (!IS_ALIGNED(len, bs) && destoff + len < inode->i_size) + goto out_unlock; + len = ALIGN(src->i_size, bs) - off; + } + + if (len == 0) { + ret = 0; + goto out_unlock; + } + + /* verify the end result is block aligned */ + if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) || + !IS_ALIGNED(destoff, bs)) + goto out_unlock; + + /* verify if ranges are overlapped within the same file */ + if (same_inode) { + if (destoff + len > off && destoff < off + len) + goto out_unlock; + } + + if (destoff > inode->i_size) { + ret = btrfs_cont_expand(inode, inode->i_size, destoff); + if (ret) + goto out_unlock; + } + + /* + * Lock the target range too. Right after we replace the file extent + * items in the fs tree (which now point to the cloned data), we might + * have a worker replace them with extent items relative to a write + * operation that was issued before this clone operation (i.e. confront + * with inode.c:btrfs_finish_ordered_io). + */ + if (same_inode) { + u64 lock_start = min_t(u64, off, destoff); + u64 lock_len = max_t(u64, off, destoff) + len - lock_start; + + ret = lock_extent_range(src, lock_start, lock_len, true); + } else { + ret = btrfs_double_extent_lock(src, off, inode, destoff, len, + true); + } + ASSERT(ret == 0); + if (WARN_ON(ret)) { + /* ranges in the io trees already unlocked */ + goto out_unlock; + } + + ret = btrfs_clone(src, inode, off, olen, len, destoff, 0); + + if (same_inode) { + u64 lock_start = min_t(u64, off, destoff); + u64 lock_end = max_t(u64, off, destoff) + len - 1; + + unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end); + } else { + btrfs_double_extent_unlock(src, off, inode, destoff, len); + } + /* + * Truncate page cache pages so that future reads will see the cloned + * data immediately and not the previous data. + */ + truncate_inode_pages_range(&inode->i_data, + round_down(destoff, PAGE_SIZE), + round_up(destoff + len, PAGE_SIZE) - 1); +out_unlock: + if (!same_inode) + btrfs_double_inode_unlock(src, inode); + else + inode_unlock(src); + return ret; +} + +int btrfs_clone_file_range(struct file *src_file, loff_t off, + struct file *dst_file, loff_t destoff, u64 len) +{ + return btrfs_clone_files(dst_file, src_file, off, len, destoff); +} + +static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + 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; + struct btrfs_key location; + struct btrfs_disk_key disk_key; + 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; + + location.objectid = objectid; + location.type = BTRFS_ROOT_ITEM_KEY; + location.offset = (u64)-1; + + new_root = btrfs_read_fs_root_no_name(fs_info, &location); + if (IS_ERR(new_root)) { + ret = PTR_ERR(new_root); + goto out; + } + if (!is_fstree(new_root->objectid)) { + ret = -ENOENT; + goto out; + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + path->leave_spinning = 1; + + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + btrfs_free_path(path); + ret = PTR_ERR(trans); + goto out; + } + + dir_id = btrfs_super_root_dir(fs_info->super_copy); + di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path, + dir_id, "default", 7, 1); + if (IS_ERR_OR_NULL(di)) { + btrfs_free_path(path); + btrfs_end_transaction(trans); + btrfs_err(fs_info, + "Umm, you don't have the default diritem, this isn't going to work"); + ret = -ENOENT; + goto out; + } + + btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); + btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); + btrfs_mark_buffer_dirty(path->nodes[0]); + btrfs_free_path(path); + + btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL); + btrfs_end_transaction(trans); +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_cache *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->key.offset; + space->used_bytes += + btrfs_block_group_used(&block_group->item); + } +} + +static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_space_args space_args; + struct btrfs_ioctl_space_info space; + struct btrfs_ioctl_space_info *dest; + struct btrfs_ioctl_space_info *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; + rcu_read_lock(); + list_for_each_entry_rcu(tmp, &fs_info->space_info, + list) { + if (tmp->flags == types[i]) { + info = tmp; + break; + } + } + rcu_read_unlock(); + + 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 = kmalloc(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; + rcu_read_lock(); + list_for_each_entry_rcu(tmp, &fs_info->space_info, + list) { + if (tmp->flags == types[i]) { + info = tmp; + break; + } + } + rcu_read_unlock(); + + 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, alloc_size)) + ret = -EFAULT; + + kfree(dest_orig); +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; + int ret; + + 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 = root->fs_info->last_trans_committed; + goto out; + } + transid = trans->transid; + ret = btrfs_commit_transaction_async(trans, 0); + if (ret) { + btrfs_end_transaction(trans); + return ret; + } +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) +{ + u64 transid; + + if (argp) { + if (copy_from_user(&transid, argp, sizeof(transid))) + return -EFAULT; + } else { + transid = 0; /* current trans */ + } + 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 = btrfs_sb(file_inode(file)->i_sb); + struct btrfs_ioctl_scrub_args *sa; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + if (!(sa->flags & BTRFS_SCRUB_READONLY)) { + ret = mnt_want_write_file(file); + if (ret) + goto out; + } + + ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end, + &sa->progress, sa->flags & BTRFS_SCRUB_READONLY, + 0); + + if (copy_to_user(arg, sa, sizeof(*sa))) + ret = -EFAULT; + + if (!(sa->flags & BTRFS_SCRUB_READONLY)) + mnt_drop_write_file(file); +out: + kfree(sa); + 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 *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 (copy_to_user(arg, sa, sizeof(*sa))) + ret = -EFAULT; + + kfree(sa); + return ret; +} + +static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_get_dev_stats *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)) { + kfree(sa); + return -EPERM; + } + + ret = btrfs_get_dev_stats(fs_info, sa); + + if (copy_to_user(arg, sa, sizeof(*sa))) + ret = -EFAULT; + + kfree(sa); + return ret; +} + +static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info, + void __user *arg) +{ + struct btrfs_ioctl_dev_replace_args *p; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + 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)) { + ret = -EROFS; + goto out; + } + if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + } else { + ret = btrfs_dev_replace_by_ioctl(fs_info, p); + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); + } + 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 (copy_to_user(arg, p, sizeof(*p))) + ret = -EFAULT; +out: + kfree(p); + 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 *ipa = NULL; + struct inode_fs_paths *ipath = 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; + } + + ret = copy_to_user((void __user *)(unsigned long)ipa->fspath, + ipath->fspath, size); + if (ret) { + ret = -EFAULT; + goto out; + } + +out: + btrfs_free_path(path); + free_ipath(ipath); + kfree(ipa); + + return ret; +} + +static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx) +{ + struct btrfs_data_container *inodes = ctx; + const size_t c = 3 * sizeof(u64); + + if (inodes->bytes_left >= c) { + inodes->bytes_left -= c; + inodes->val[inodes->elem_cnt] = inum; + inodes->val[inodes->elem_cnt + 1] = offset; + inodes->val[inodes->elem_cnt + 2] = root; + inodes->elem_cnt += 3; + } else { + inodes->bytes_missing += c - inodes->bytes_left; + inodes->bytes_left = 0; + inodes->elem_missed += 3; + } + + return 0; +} + +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 *loi; + struct btrfs_data_container *inodes = NULL; + struct btrfs_path *path = NULL; + 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))) { + ret = -EINVAL; + goto out_loi; + } + /* Only accept flags we have defined so far */ + if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) { + ret = -EINVAL; + goto out_loi; + } + ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET; + size = min_t(u32, loi->size, SZ_16M); + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + inodes = init_data_container(size); + if (IS_ERR(inodes)) { + ret = PTR_ERR(inodes); + inodes = NULL; + goto out; + } + + ret = iterate_inodes_from_logical(loi->logical, fs_info, path, + build_ino_list, inodes, ignore_offset); + if (ret == -EINVAL) + ret = -ENOENT; + if (ret < 0) + goto out; + + ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes, + size); + if (ret) + ret = -EFAULT; + +out: + btrfs_free_path(path); + kvfree(inodes); +out_loi: + kfree(loi); + + 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); +} + +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 *bargs; + struct btrfs_balance_control *bctl; + bool need_unlock; /* for mut. excl. ops lock */ + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + +again: + if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { + mutex_lock(&fs_info->balance_mutex); + need_unlock = true; + goto locked; + } + + /* + * mut. excl. ops lock is locked. Three possibilities: + * (1) some other op is running + * (2) balance is running + * (3) balance is paused -- special case (think resume) + */ + 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)) { + 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) */ + need_unlock = false; + goto locked; + } + + mutex_unlock(&fs_info->balance_mutex); + goto again; + } else { + /* this is (2) */ + mutex_unlock(&fs_info->balance_mutex); + ret = -EINPROGRESS; + goto out; + } + } else { + /* this is (1) */ + mutex_unlock(&fs_info->balance_mutex); + ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; + goto out; + } + +locked: + BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)); + + if (arg) { + bargs = memdup_user(arg, sizeof(*bargs)); + if (IS_ERR(bargs)) { + ret = PTR_ERR(bargs); + goto out_unlock; + } + + if (bargs->flags & BTRFS_BALANCE_RESUME) { + if (!fs_info->balance_ctl) { + ret = -ENOTCONN; + goto out_bargs; + } + + bctl = fs_info->balance_ctl; + spin_lock(&fs_info->balance_lock); + bctl->flags |= BTRFS_BALANCE_RESUME; + spin_unlock(&fs_info->balance_lock); + + goto do_balance; + } + } else { + bargs = NULL; + } + + if (fs_info->balance_ctl) { + ret = -EINPROGRESS; + goto out_bargs; + } + + bctl = kzalloc(sizeof(*bctl), GFP_KERNEL); + if (!bctl) { + ret = -ENOMEM; + goto out_bargs; + } + + if (arg) { + 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; + } else { + /* balance everything - no filters */ + bctl->flags |= BTRFS_BALANCE_TYPE_MASK; + } + + if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) { + ret = -EINVAL; + goto out_bctl; + } + +do_balance: + /* + * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP 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 (arg) { + if (copy_to_user(arg, bargs, sizeof(*bargs))) + ret = -EFAULT; + } + +out_bctl: + kfree(bctl); +out_bargs: + kfree(bargs); +out_unlock: + mutex_unlock(&fs_info->balance_mutex); + if (need_unlock) + clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); +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 *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; + + kfree(bargs); +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 = btrfs_sb(inode->i_sb); + struct btrfs_ioctl_quota_ctl_args *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; + } + + down_write(&fs_info->subvol_sem); + + switch (sa->cmd) { + case BTRFS_QUOTA_CTL_ENABLE: + ret = btrfs_quota_enable(fs_info); + break; + case BTRFS_QUOTA_CTL_DISABLE: + ret = btrfs_quota_disable(fs_info); + break; + default: + ret = -EINVAL; + break; + } + + kfree(sa); + up_write(&fs_info->subvol_sem); +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 = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_ioctl_qgroup_assign_args *sa; + struct btrfs_trans_handle *trans; + int ret; + int err; + + 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; + } + + trans = btrfs_join_transaction(root); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out; + } + + if (sa->assign) { + ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst); + } else { + ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst); + } + + /* update qgroup status and info */ + err = btrfs_run_qgroups(trans); + if (err < 0) + btrfs_handle_fs_error(fs_info, err, + "failed to update qgroup status and info"); + err = btrfs_end_transaction(trans); + if (err && !ret) + ret = err; + +out: + kfree(sa); +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_root *root = BTRFS_I(inode)->root; + struct btrfs_ioctl_qgroup_create_args *sa; + struct btrfs_trans_handle *trans; + int ret; + int err; + + 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; + } + + if (!sa->qgroupid) { + ret = -EINVAL; + goto out; + } + + trans = btrfs_join_transaction(root); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out; + } + + if (sa->create) { + ret = btrfs_create_qgroup(trans, sa->qgroupid); + } else { + ret = btrfs_remove_qgroup(trans, sa->qgroupid); + } + + err = btrfs_end_transaction(trans); + if (err && !ret) + ret = err; + +out: + kfree(sa); +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_ioctl_qgroup_limit_args *sa; + struct btrfs_trans_handle *trans; + int ret; + int err; + u64 qgroupid; + + 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; + } + + trans = btrfs_join_transaction(root); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out; + } + + qgroupid = sa->qgroupid; + if (!qgroupid) { + /* take the current subvol as qgroup */ + qgroupid = root->root_key.objectid; + } + + ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim); + + err = btrfs_end_transaction(trans); + if (err && !ret) + ret = err; + +out: + kfree(sa); +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 = btrfs_sb(inode->i_sb); + struct btrfs_ioctl_quota_rescan_args *qsa; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + 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 out; + } + + ret = btrfs_qgroup_rescan(fs_info); + +out: + kfree(qsa); +drop_write: + mnt_drop_write_file(file); + return ret; +} + +static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_ioctl_quota_rescan_args *qsa; + int ret = 0; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + qsa = kzalloc(sizeof(*qsa), GFP_KERNEL); + if (!qsa) + return -ENOMEM; + + 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))) + ret = -EFAULT; + + kfree(qsa); + return ret; +} + +static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + + 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 btrfs_ioctl_received_subvol_args *sa) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + 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(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; + } + + /* + * 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; + + received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid, + BTRFS_UUID_SIZE); + 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, + root->root_key.objectid); + if (ret && ret != -ENOENT) { + btrfs_abort_transaction(trans, ret); + 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 (ret < 0) { + 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, + root->root_key.objectid); + if (ret < 0 && ret != -EEXIST) { + 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 *args32 = NULL; + struct btrfs_ioctl_received_subvol_args *args64 = NULL; + int ret = 0; + + args32 = memdup_user(arg, sizeof(*args32)); + if (IS_ERR(args32)) + return PTR_ERR(args32); + + args64 = kmalloc(sizeof(*args64), GFP_KERNEL); + if (!args64) { + ret = -ENOMEM; + goto out; + } + + 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, args64); + if (ret) + goto out; + + 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) + ret = -EFAULT; + +out: + kfree(args32); + kfree(args64); + return ret; +} +#endif + +static long btrfs_ioctl_set_received_subvol(struct file *file, + void __user *arg) +{ + struct btrfs_ioctl_received_subvol_args *sa = NULL; + int ret = 0; + + sa = memdup_user(arg, sizeof(*sa)); + if (IS_ERR(sa)) + return PTR_ERR(sa); + + ret = _btrfs_ioctl_set_received_subvol(file, sa); + + if (ret) + goto out; + + ret = copy_to_user(arg, sa, sizeof(*sa)); + if (ret) + ret = -EFAULT; + +out: + kfree(sa); + return ret; +} + +static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + 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 = btrfs_sb(inode->i_sb); + 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); + strcpy(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 file *file, void __user *arg) +{ + struct inode *inode = file_inode(file); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + 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(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_names[set]; + char *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" : ""); + kfree(names); + } 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" : ""); + kfree(names); + } 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" : ""); + kfree(names); + } 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 = btrfs_sb(inode->i_sb); + 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 file *file, void __user *argp, bool compat) +{ + struct btrfs_ioctl_send_args *arg; + int ret; + + if (compat) { +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + struct btrfs_ioctl_send_args_32 args32; + + ret = copy_from_user(&args32, argp, sizeof(args32)); + if (ret) + return -EFAULT; + arg = kzalloc(sizeof(*arg), GFP_KERNEL); + 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; + 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); + } + ret = btrfs_ioctl_send(file, arg); + kfree(arg); + 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 = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + void __user *argp = (void __user *)arg; + + switch (cmd) { + case FS_IOC_GETFLAGS: + return btrfs_ioctl_getflags(file, argp); + case FS_IOC_SETFLAGS: + return btrfs_ioctl_setflags(file, argp); + case FS_IOC_GETVERSION: + return btrfs_ioctl_getversion(file, argp); + case FITRIM: + return btrfs_ioctl_fitrim(file, argp); + case BTRFS_IOC_SNAP_CREATE: + return btrfs_ioctl_snap_create(file, argp, 0); + case BTRFS_IOC_SNAP_CREATE_V2: + return btrfs_ioctl_snap_create_v2(file, argp, 0); + case BTRFS_IOC_SUBVOL_CREATE: + return btrfs_ioctl_snap_create(file, argp, 1); + case BTRFS_IOC_SUBVOL_CREATE_V2: + return btrfs_ioctl_snap_create_v2(file, argp, 1); + case BTRFS_IOC_SNAP_DESTROY: + return btrfs_ioctl_snap_destroy(file, argp); + case BTRFS_IOC_SUBVOL_GETFLAGS: + return btrfs_ioctl_subvol_getflags(file, 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_BALANCE: + return btrfs_ioctl_balance(file, NULL); + case BTRFS_IOC_TREE_SEARCH: + return btrfs_ioctl_tree_search(file, argp); + case BTRFS_IOC_TREE_SEARCH_V2: + return btrfs_ioctl_tree_search_v2(file, argp); + case BTRFS_IOC_INO_LOOKUP: + return btrfs_ioctl_ino_lookup(file, 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, -1); + if (ret) + return ret; + ret = btrfs_sync_fs(inode->i_sb, 1); + /* + * The transaction thread may want to do more work, + * namely it pokes the cleaner kthread that will start + * processing uncleaned subvols. + */ + wake_up_process(fs_info->transaction_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(file, argp, false); +#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) + case BTRFS_IOC_SEND_32: + return _btrfs_ioctl_send(file, 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(file, argp); + case BTRFS_IOC_QUOTA_RESCAN_WAIT: + return btrfs_ioctl_quota_rescan_wait(file, argp); + case BTRFS_IOC_DEV_REPLACE: + return btrfs_ioctl_dev_replace(fs_info, argp); + case BTRFS_IOC_GET_FSLABEL: + return btrfs_ioctl_get_fslabel(file, argp); + case BTRFS_IOC_SET_FSLABEL: + return btrfs_ioctl_set_fslabel(file, argp); + case BTRFS_IOC_GET_SUPPORTED_FEATURES: + return btrfs_ioctl_get_supported_features(argp); + case BTRFS_IOC_GET_FEATURES: + return btrfs_ioctl_get_features(file, argp); + case BTRFS_IOC_SET_FEATURES: + return btrfs_ioctl_set_features(file, argp); + case FS_IOC_FSGETXATTR: + return btrfs_ioctl_fsgetxattr(file, argp); + case FS_IOC_FSSETXATTR: + return btrfs_ioctl_fssetxattr(file, argp); + case BTRFS_IOC_GET_SUBVOL_INFO: + return btrfs_ioctl_get_subvol_info(file, argp); + case BTRFS_IOC_GET_SUBVOL_ROOTREF: + return btrfs_ioctl_get_subvol_rootref(file, argp); + case BTRFS_IOC_INO_LOOKUP_USER: + return btrfs_ioctl_ino_lookup_user(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_GETFLAGS: + cmd = FS_IOC_GETFLAGS; + break; + case FS_IOC32_SETFLAGS: + cmd = FS_IOC_SETFLAGS; + break; + case FS_IOC32_GETVERSION: + cmd = FS_IOC_GETVERSION; + break; + } + + return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); +} +#endif |