|  | // SPDX-License-Identifier: GPL-2.0 | 
|  | /* | 
|  | * Copyright (C) 2007 Oracle.  All rights reserved. | 
|  | */ | 
|  |  | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/bio.h> | 
|  | #include <linux/file.h> | 
|  | #include <linux/fs.h> | 
|  | #include <linux/fsnotify.h> | 
|  | #include <linux/pagemap.h> | 
|  | #include <linux/highmem.h> | 
|  | #include <linux/time.h> | 
|  | #include <linux/string.h> | 
|  | #include <linux/backing-dev.h> | 
|  | #include <linux/mount.h> | 
|  | #include <linux/namei.h> | 
|  | #include <linux/writeback.h> | 
|  | #include <linux/compat.h> | 
|  | #include <linux/security.h> | 
|  | #include <linux/xattr.h> | 
|  | #include <linux/mm.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/blkdev.h> | 
|  | #include <linux/uuid.h> | 
|  | #include <linux/btrfs.h> | 
|  | #include <linux/uaccess.h> | 
|  | #include <linux/iversion.h> | 
|  | #include <linux/fileattr.h> | 
|  | #include <linux/fsverity.h> | 
|  | #include <linux/sched/xacct.h> | 
|  | #include "ctree.h" | 
|  | #include "disk-io.h" | 
|  | #include "export.h" | 
|  | #include "transaction.h" | 
|  | #include "btrfs_inode.h" | 
|  | #include "volumes.h" | 
|  | #include "locking.h" | 
|  | #include "backref.h" | 
|  | #include "send.h" | 
|  | #include "dev-replace.h" | 
|  | #include "props.h" | 
|  | #include "sysfs.h" | 
|  | #include "qgroup.h" | 
|  | #include "tree-log.h" | 
|  | #include "compression.h" | 
|  | #include "space-info.h" | 
|  | #include "block-group.h" | 
|  | #include "fs.h" | 
|  | #include "accessors.h" | 
|  | #include "extent-tree.h" | 
|  | #include "root-tree.h" | 
|  | #include "defrag.h" | 
|  | #include "dir-item.h" | 
|  | #include "uuid-tree.h" | 
|  | #include "ioctl.h" | 
|  | #include "file.h" | 
|  | #include "scrub.h" | 
|  | #include "super.h" | 
|  |  | 
|  | #ifdef CONFIG_64BIT | 
|  | /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI | 
|  | * structures are incorrect, as the timespec structure from userspace | 
|  | * is 4 bytes too small. We define these alternatives here to teach | 
|  | * the kernel about the 32-bit struct packing. | 
|  | */ | 
|  | struct btrfs_ioctl_timespec_32 { | 
|  | __u64 sec; | 
|  | __u32 nsec; | 
|  | } __attribute__ ((__packed__)); | 
|  |  | 
|  | struct btrfs_ioctl_received_subvol_args_32 { | 
|  | char	uuid[BTRFS_UUID_SIZE];	/* in */ | 
|  | __u64	stransid;		/* in */ | 
|  | __u64	rtransid;		/* out */ | 
|  | struct btrfs_ioctl_timespec_32 stime; /* in */ | 
|  | struct btrfs_ioctl_timespec_32 rtime; /* out */ | 
|  | __u64	flags;			/* in */ | 
|  | __u64	reserved[16];		/* in */ | 
|  | } __attribute__ ((__packed__)); | 
|  |  | 
|  | #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \ | 
|  | struct btrfs_ioctl_received_subvol_args_32) | 
|  | #endif | 
|  |  | 
|  | #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) | 
|  | struct btrfs_ioctl_send_args_32 { | 
|  | __s64 send_fd;			/* in */ | 
|  | __u64 clone_sources_count;	/* in */ | 
|  | compat_uptr_t clone_sources;	/* in */ | 
|  | __u64 parent_root;		/* in */ | 
|  | __u64 flags;			/* in */ | 
|  | __u32 version;			/* in */ | 
|  | __u8  reserved[28];		/* in */ | 
|  | } __attribute__ ((__packed__)); | 
|  |  | 
|  | #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \ | 
|  | struct btrfs_ioctl_send_args_32) | 
|  |  | 
|  | struct btrfs_ioctl_encoded_io_args_32 { | 
|  | compat_uptr_t iov; | 
|  | compat_ulong_t iovcnt; | 
|  | __s64 offset; | 
|  | __u64 flags; | 
|  | __u64 len; | 
|  | __u64 unencoded_len; | 
|  | __u64 unencoded_offset; | 
|  | __u32 compression; | 
|  | __u32 encryption; | 
|  | __u8 reserved[64]; | 
|  | }; | 
|  |  | 
|  | #define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \ | 
|  | struct btrfs_ioctl_encoded_io_args_32) | 
|  | #define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \ | 
|  | struct btrfs_ioctl_encoded_io_args_32) | 
|  | #endif | 
|  |  | 
|  | /* Mask out flags that are inappropriate for the given type of inode. */ | 
|  | static unsigned int btrfs_mask_fsflags_for_type(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(struct btrfs_inode *binode) | 
|  | { | 
|  | unsigned int iflags = 0; | 
|  | u32 flags = binode->flags; | 
|  | u32 ro_flags = binode->ro_flags; | 
|  |  | 
|  | if (flags & BTRFS_INODE_SYNC) | 
|  | iflags |= FS_SYNC_FL; | 
|  | if (flags & BTRFS_INODE_IMMUTABLE) | 
|  | iflags |= FS_IMMUTABLE_FL; | 
|  | if (flags & BTRFS_INODE_APPEND) | 
|  | iflags |= FS_APPEND_FL; | 
|  | if (flags & BTRFS_INODE_NODUMP) | 
|  | iflags |= FS_NODUMP_FL; | 
|  | if (flags & BTRFS_INODE_NOATIME) | 
|  | iflags |= FS_NOATIME_FL; | 
|  | if (flags & BTRFS_INODE_DIRSYNC) | 
|  | iflags |= FS_DIRSYNC_FL; | 
|  | if (flags & BTRFS_INODE_NODATACOW) | 
|  | iflags |= FS_NOCOW_FL; | 
|  | if (ro_flags & BTRFS_INODE_RO_VERITY) | 
|  | iflags |= FS_VERITY_FL; | 
|  |  | 
|  | if (flags & BTRFS_INODE_NOCOMPRESS) | 
|  | iflags |= FS_NOCOMP_FL; | 
|  | else if (flags & BTRFS_INODE_COMPRESS) | 
|  | iflags |= FS_COMPR_FL; | 
|  |  | 
|  | return iflags; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Update inode->i_flags based on the btrfs internal flags. | 
|  | */ | 
|  | void btrfs_sync_inode_flags_to_i_flags(struct 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; | 
|  | if (binode->ro_flags & BTRFS_INODE_RO_VERITY) | 
|  | new_fl |= S_VERITY; | 
|  |  | 
|  | set_mask_bits(&inode->i_flags, | 
|  | S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC | | 
|  | S_VERITY, new_fl); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Check if @flags are a supported and valid set of FS_*_FL flags and that | 
|  | * the old and new flags are not conflicting | 
|  | */ | 
|  | static int check_fsflags(unsigned int old_flags, unsigned int flags) | 
|  | { | 
|  | if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \ | 
|  | FS_NOATIME_FL | FS_NODUMP_FL | \ | 
|  | FS_SYNC_FL | FS_DIRSYNC_FL | \ | 
|  | FS_NOCOMP_FL | FS_COMPR_FL | | 
|  | FS_NOCOW_FL)) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | /* COMPR and NOCOMP on new/old are valid */ | 
|  | if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL)) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* NOCOW and compression options are mutually exclusive */ | 
|  | if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL))) | 
|  | return -EINVAL; | 
|  | if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL))) | 
|  | return -EINVAL; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int check_fsflags_compatible(struct btrfs_fs_info *fs_info, | 
|  | unsigned int flags) | 
|  | { | 
|  | if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL)) | 
|  | return -EPERM; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | int btrfs_check_ioctl_vol_args_path(const struct btrfs_ioctl_vol_args *vol_args) | 
|  | { | 
|  | if (memchr(vol_args->name, 0, sizeof(vol_args->name)) == NULL) | 
|  | return -ENAMETOOLONG; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int btrfs_check_ioctl_vol_args2_subvol_name(const struct btrfs_ioctl_vol_args_v2 *vol_args2) | 
|  | { | 
|  | if (memchr(vol_args2->name, 0, sizeof(vol_args2->name)) == NULL) | 
|  | return -ENAMETOOLONG; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Set flags/xflags from the internal inode flags. The remaining items of | 
|  | * fsxattr are zeroed. | 
|  | */ | 
|  | int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa) | 
|  | { | 
|  | struct btrfs_inode *binode = BTRFS_I(d_inode(dentry)); | 
|  |  | 
|  | fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode)); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | int btrfs_fileattr_set(struct mnt_idmap *idmap, | 
|  | struct dentry *dentry, struct fileattr *fa) | 
|  | { | 
|  | struct inode *inode = d_inode(dentry); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | 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; | 
|  | const char *comp = NULL; | 
|  | u32 binode_flags; | 
|  |  | 
|  | if (btrfs_root_readonly(root)) | 
|  | return -EROFS; | 
|  |  | 
|  | if (fileattr_has_fsx(fa)) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags); | 
|  | old_fsflags = btrfs_inode_flags_to_fsflags(binode); | 
|  | ret = check_fsflags(old_fsflags, fsflags); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = check_fsflags_compatible(fs_info, fsflags); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | binode_flags = binode->flags; | 
|  | 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 coming from FS_IOC_FSSETXATTR then skip unconverted flags */ | 
|  | if (!fa->flags_valid) { | 
|  | /* 1 item for the inode */ | 
|  | trans = btrfs_start_transaction(root, 1); | 
|  | if (IS_ERR(trans)) | 
|  | return PTR_ERR(trans); | 
|  | goto update_flags; | 
|  | } | 
|  |  | 
|  | if (fsflags & FS_DIRSYNC_FL) | 
|  | binode_flags |= BTRFS_INODE_DIRSYNC; | 
|  | else | 
|  | binode_flags &= ~BTRFS_INODE_DIRSYNC; | 
|  | if (fsflags & FS_NOCOW_FL) { | 
|  | if (S_ISREG(inode->i_mode)) { | 
|  | /* | 
|  | * It's safe to turn csums off here, no extents exist. | 
|  | * Otherwise we want the flag to reflect the real COW | 
|  | * status of the file and will not set it. | 
|  | */ | 
|  | if (inode->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(inode->i_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; | 
|  | } else if (fsflags & FS_COMPR_FL) { | 
|  |  | 
|  | if (IS_SWAPFILE(inode)) | 
|  | return -ETXTBSY; | 
|  |  | 
|  | 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); | 
|  | } else { | 
|  | binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * 1 for inode item | 
|  | * 2 for properties | 
|  | */ | 
|  | trans = btrfs_start_transaction(root, 3); | 
|  | if (IS_ERR(trans)) | 
|  | return PTR_ERR(trans); | 
|  |  | 
|  | if (comp) { | 
|  | ret = btrfs_set_prop(trans, BTRFS_I(inode), "btrfs.compression", | 
|  | comp, strlen(comp), 0); | 
|  | if (ret) { | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out_end_trans; | 
|  | } | 
|  | } else { | 
|  | ret = btrfs_set_prop(trans, BTRFS_I(inode), "btrfs.compression", | 
|  | NULL, 0, 0); | 
|  | if (ret && ret != -ENODATA) { | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out_end_trans; | 
|  | } | 
|  | } | 
|  |  | 
|  | update_flags: | 
|  | binode->flags = binode_flags; | 
|  | btrfs_sync_inode_flags_to_i_flags(inode); | 
|  | inode_inc_iversion(inode); | 
|  | inode_set_ctime_current(inode); | 
|  | ret = btrfs_update_inode(trans, BTRFS_I(inode)); | 
|  |  | 
|  | out_end_trans: | 
|  | btrfs_end_transaction(trans); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Start exclusive operation @type, return true on success | 
|  | */ | 
|  | bool btrfs_exclop_start(struct btrfs_fs_info *fs_info, | 
|  | enum btrfs_exclusive_operation type) | 
|  | { | 
|  | bool ret = false; | 
|  |  | 
|  | spin_lock(&fs_info->super_lock); | 
|  | if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) { | 
|  | fs_info->exclusive_operation = type; | 
|  | ret = true; | 
|  | } | 
|  | spin_unlock(&fs_info->super_lock); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Conditionally allow to enter the exclusive operation in case it's compatible | 
|  | * with the running one.  This must be paired with btrfs_exclop_start_unlock and | 
|  | * btrfs_exclop_finish. | 
|  | * | 
|  | * Compatibility: | 
|  | * - the same type is already running | 
|  | * - when trying to add a device and balance has been paused | 
|  | * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller | 
|  | *   must check the condition first that would allow none -> @type | 
|  | */ | 
|  | bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info, | 
|  | enum btrfs_exclusive_operation type) | 
|  | { | 
|  | spin_lock(&fs_info->super_lock); | 
|  | if (fs_info->exclusive_operation == type || | 
|  | (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED && | 
|  | type == BTRFS_EXCLOP_DEV_ADD)) | 
|  | return true; | 
|  |  | 
|  | spin_unlock(&fs_info->super_lock); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info) | 
|  | { | 
|  | spin_unlock(&fs_info->super_lock); | 
|  | } | 
|  |  | 
|  | void btrfs_exclop_finish(struct btrfs_fs_info *fs_info) | 
|  | { | 
|  | spin_lock(&fs_info->super_lock); | 
|  | WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE); | 
|  | spin_unlock(&fs_info->super_lock); | 
|  | sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation"); | 
|  | } | 
|  |  | 
|  | void btrfs_exclop_balance(struct btrfs_fs_info *fs_info, | 
|  | enum btrfs_exclusive_operation op) | 
|  | { | 
|  | switch (op) { | 
|  | case BTRFS_EXCLOP_BALANCE_PAUSED: | 
|  | spin_lock(&fs_info->super_lock); | 
|  | ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE || | 
|  | fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD || | 
|  | fs_info->exclusive_operation == BTRFS_EXCLOP_NONE || | 
|  | fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED); | 
|  | fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED; | 
|  | spin_unlock(&fs_info->super_lock); | 
|  | break; | 
|  | case BTRFS_EXCLOP_BALANCE: | 
|  | spin_lock(&fs_info->super_lock); | 
|  | ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED); | 
|  | fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE; | 
|  | spin_unlock(&fs_info->super_lock); | 
|  | break; | 
|  | default: | 
|  | btrfs_warn(fs_info, | 
|  | "invalid exclop balance operation %d requested", op); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg) | 
|  | { | 
|  | return put_user(inode->i_generation, arg); | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | struct btrfs_device *device; | 
|  | struct fstrim_range range; | 
|  | u64 minlen = ULLONG_MAX; | 
|  | u64 num_devices = 0; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | /* | 
|  | * btrfs_trim_block_group() depends on space cache, which is not | 
|  | * available in zoned filesystem. So, disallow fitrim on a zoned | 
|  | * filesystem for now. | 
|  | */ | 
|  | if (btrfs_is_zoned(fs_info)) | 
|  | return -EOPNOTSUPP; | 
|  |  | 
|  | /* | 
|  | * If the fs is mounted with nologreplay, which requires it to be | 
|  | * mounted in RO mode as well, we can not allow discard on free space | 
|  | * inside block groups, because log trees refer to extents that are not | 
|  | * pinned in a block group's free space cache (pinning the extents is | 
|  | * precisely the first phase of replaying a log tree). | 
|  | */ | 
|  | if (btrfs_test_opt(fs_info, NOLOGREPLAY)) | 
|  | return -EROFS; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | list_for_each_entry_rcu(device, &fs_info->fs_devices->devices, | 
|  | dev_list) { | 
|  | if (!device->bdev || !bdev_max_discard_sectors(device->bdev)) | 
|  | continue; | 
|  | num_devices++; | 
|  | minlen = min_t(u64, bdev_discard_granularity(device->bdev), | 
|  | minlen); | 
|  | } | 
|  | rcu_read_unlock(); | 
|  |  | 
|  | if (!num_devices) | 
|  | return -EOPNOTSUPP; | 
|  | if (copy_from_user(&range, arg, sizeof(range))) | 
|  | return -EFAULT; | 
|  |  | 
|  | /* | 
|  | * NOTE: Don't truncate the range using super->total_bytes.  Bytenr of | 
|  | * block group is in the logical address space, which can be any | 
|  | * sectorsize aligned bytenr in  the range [0, U64_MAX]. | 
|  | */ | 
|  | if (range.len < fs_info->sectorsize) | 
|  | return -EINVAL; | 
|  |  | 
|  | range.minlen = max(range.minlen, minlen); | 
|  | ret = btrfs_trim_fs(fs_info, &range); | 
|  |  | 
|  | if (copy_to_user(arg, &range, sizeof(range))) | 
|  | return -EFAULT; | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | int __pure btrfs_is_empty_uuid(const u8 *uuid) | 
|  | { | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < BTRFS_UUID_SIZE; i++) { | 
|  | if (uuid[i]) | 
|  | return 0; | 
|  | } | 
|  | return 1; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Calculate the number of transaction items to reserve for creating a subvolume | 
|  | * or snapshot, not including the inode, directory entries, or parent directory. | 
|  | */ | 
|  | static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit) | 
|  | { | 
|  | /* | 
|  | * 1 to add root block | 
|  | * 1 to add root item | 
|  | * 1 to add root ref | 
|  | * 1 to add root backref | 
|  | * 1 to add UUID item | 
|  | * 1 to add qgroup info | 
|  | * 1 to add qgroup limit | 
|  | * | 
|  | * Ideally the last two would only be accounted if qgroups are enabled, | 
|  | * but that can change between now and the time we would insert them. | 
|  | */ | 
|  | unsigned int num_items = 7; | 
|  |  | 
|  | if (inherit) { | 
|  | /* 2 to add qgroup relations for each inherited qgroup */ | 
|  | num_items += 2 * inherit->num_qgroups; | 
|  | } | 
|  | return num_items; | 
|  | } | 
|  |  | 
|  | static noinline int create_subvol(struct mnt_idmap *idmap, | 
|  | struct inode *dir, struct dentry *dentry, | 
|  | struct btrfs_qgroup_inherit *inherit) | 
|  | { | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); | 
|  | struct btrfs_trans_handle *trans; | 
|  | struct btrfs_key key; | 
|  | struct btrfs_root_item *root_item; | 
|  | struct btrfs_inode_item *inode_item; | 
|  | struct extent_buffer *leaf; | 
|  | struct btrfs_root *root = BTRFS_I(dir)->root; | 
|  | struct btrfs_root *new_root; | 
|  | struct btrfs_block_rsv block_rsv; | 
|  | struct timespec64 cur_time = current_time(dir); | 
|  | struct btrfs_new_inode_args new_inode_args = { | 
|  | .dir = dir, | 
|  | .dentry = dentry, | 
|  | .subvol = true, | 
|  | }; | 
|  | unsigned int trans_num_items; | 
|  | int ret; | 
|  | dev_t anon_dev; | 
|  | u64 objectid; | 
|  | u64 qgroup_reserved = 0; | 
|  |  | 
|  | root_item = kzalloc(sizeof(*root_item), GFP_KERNEL); | 
|  | if (!root_item) | 
|  | return -ENOMEM; | 
|  |  | 
|  | ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid); | 
|  | if (ret) | 
|  | goto out_root_item; | 
|  |  | 
|  | /* | 
|  | * 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 out_root_item; | 
|  | } | 
|  |  | 
|  | ret = get_anon_bdev(&anon_dev); | 
|  | if (ret < 0) | 
|  | goto out_root_item; | 
|  |  | 
|  | new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir); | 
|  | if (!new_inode_args.inode) { | 
|  | ret = -ENOMEM; | 
|  | goto out_anon_dev; | 
|  | } | 
|  | ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items); | 
|  | if (ret) | 
|  | goto out_inode; | 
|  | trans_num_items += create_subvol_num_items(inherit); | 
|  |  | 
|  | btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP); | 
|  | ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, | 
|  | trans_num_items, false); | 
|  | if (ret) | 
|  | goto out_new_inode_args; | 
|  | qgroup_reserved = block_rsv.qgroup_rsv_reserved; | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 0); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_release_rsv; | 
|  | } | 
|  | btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); | 
|  | qgroup_reserved = 0; | 
|  | trans->block_rsv = &block_rsv; | 
|  | trans->bytes_reserved = block_rsv.size; | 
|  |  | 
|  | ret = btrfs_qgroup_inherit(trans, 0, objectid, btrfs_root_id(root), inherit); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0, | 
|  | 0, BTRFS_NESTING_NORMAL); | 
|  | if (IS_ERR(leaf)) { | 
|  | ret = PTR_ERR(leaf); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | btrfs_mark_buffer_dirty(trans, leaf); | 
|  |  | 
|  | inode_item = &root_item->inode; | 
|  | btrfs_set_stack_inode_generation(inode_item, 1); | 
|  | btrfs_set_stack_inode_size(inode_item, 3); | 
|  | btrfs_set_stack_inode_nlink(inode_item, 1); | 
|  | btrfs_set_stack_inode_nbytes(inode_item, | 
|  | fs_info->nodesize); | 
|  | btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755); | 
|  |  | 
|  | btrfs_set_root_flags(root_item, 0); | 
|  | btrfs_set_root_limit(root_item, 0); | 
|  | btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT); | 
|  |  | 
|  | btrfs_set_root_bytenr(root_item, leaf->start); | 
|  | btrfs_set_root_generation(root_item, trans->transid); | 
|  | btrfs_set_root_level(root_item, 0); | 
|  | btrfs_set_root_refs(root_item, 1); | 
|  | btrfs_set_root_used(root_item, leaf->len); | 
|  | btrfs_set_root_last_snapshot(root_item, 0); | 
|  |  | 
|  | btrfs_set_root_generation_v2(root_item, | 
|  | btrfs_root_generation(root_item)); | 
|  | generate_random_guid(root_item->uuid); | 
|  | btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec); | 
|  | btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec); | 
|  | root_item->ctime = root_item->otime; | 
|  | btrfs_set_root_ctransid(root_item, trans->transid); | 
|  | btrfs_set_root_otransid(root_item, trans->transid); | 
|  |  | 
|  | btrfs_tree_unlock(leaf); | 
|  |  | 
|  | btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID); | 
|  |  | 
|  | key.objectid = objectid; | 
|  | key.offset = 0; | 
|  | key.type = BTRFS_ROOT_ITEM_KEY; | 
|  | ret = btrfs_insert_root(trans, fs_info->tree_root, &key, | 
|  | root_item); | 
|  | if (ret) { | 
|  | int ret2; | 
|  |  | 
|  | /* | 
|  | * Since we don't abort the transaction in this case, free the | 
|  | * tree block so that we don't leak space and leave the | 
|  | * filesystem in an inconsistent state (an extent item in the | 
|  | * extent tree with a backreference for a root that does not | 
|  | * exists). | 
|  | */ | 
|  | btrfs_tree_lock(leaf); | 
|  | btrfs_clear_buffer_dirty(trans, leaf); | 
|  | btrfs_tree_unlock(leaf); | 
|  | ret2 = btrfs_free_tree_block(trans, objectid, leaf, 0, 1); | 
|  | if (ret2 < 0) | 
|  | btrfs_abort_transaction(trans, ret2); | 
|  | free_extent_buffer(leaf); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | free_extent_buffer(leaf); | 
|  | leaf = NULL; | 
|  |  | 
|  | new_root = btrfs_get_new_fs_root(fs_info, objectid, &anon_dev); | 
|  | if (IS_ERR(new_root)) { | 
|  | ret = PTR_ERR(new_root); | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out; | 
|  | } | 
|  | /* anon_dev is owned by new_root now. */ | 
|  | anon_dev = 0; | 
|  | BTRFS_I(new_inode_args.inode)->root = new_root; | 
|  | /* ... and new_root is owned by new_inode_args.inode now. */ | 
|  |  | 
|  | ret = btrfs_record_root_in_trans(trans, new_root); | 
|  | if (ret) { | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = btrfs_uuid_tree_add(trans, root_item->uuid, | 
|  | BTRFS_UUID_KEY_SUBVOL, objectid); | 
|  | if (ret) { | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | btrfs_record_new_subvolume(trans, BTRFS_I(dir)); | 
|  |  | 
|  | ret = btrfs_create_new_inode(trans, &new_inode_args); | 
|  | if (ret) { | 
|  | btrfs_abort_transaction(trans, ret); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | d_instantiate_new(dentry, new_inode_args.inode); | 
|  | new_inode_args.inode = NULL; | 
|  |  | 
|  | out: | 
|  | trans->block_rsv = NULL; | 
|  | trans->bytes_reserved = 0; | 
|  | btrfs_end_transaction(trans); | 
|  | out_release_rsv: | 
|  | btrfs_block_rsv_release(fs_info, &block_rsv, (u64)-1, NULL); | 
|  | if (qgroup_reserved) | 
|  | btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved); | 
|  | out_new_inode_args: | 
|  | btrfs_new_inode_args_destroy(&new_inode_args); | 
|  | out_inode: | 
|  | iput(new_inode_args.inode); | 
|  | out_anon_dev: | 
|  | if (anon_dev) | 
|  | free_anon_bdev(anon_dev); | 
|  | out_root_item: | 
|  | kfree(root_item); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int create_snapshot(struct btrfs_root *root, struct inode *dir, | 
|  | struct dentry *dentry, bool readonly, | 
|  | struct btrfs_qgroup_inherit *inherit) | 
|  | { | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); | 
|  | struct inode *inode; | 
|  | struct btrfs_pending_snapshot *pending_snapshot; | 
|  | unsigned int trans_num_items; | 
|  | struct btrfs_trans_handle *trans; | 
|  | struct btrfs_block_rsv *block_rsv; | 
|  | u64 qgroup_reserved = 0; | 
|  | int ret; | 
|  |  | 
|  | /* We do not support snapshotting right now. */ | 
|  | if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { | 
|  | btrfs_warn(fs_info, | 
|  | "extent tree v2 doesn't support snapshotting yet"); | 
|  | return -EOPNOTSUPP; | 
|  | } | 
|  |  | 
|  | if (btrfs_root_refs(&root->root_item) == 0) | 
|  | return -ENOENT; | 
|  |  | 
|  | if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (atomic_read(&root->nr_swapfiles)) { | 
|  | btrfs_warn(fs_info, | 
|  | "cannot snapshot subvolume with active swapfile"); | 
|  | return -ETXTBSY; | 
|  | } | 
|  |  | 
|  | pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL); | 
|  | if (!pending_snapshot) | 
|  | return -ENOMEM; | 
|  |  | 
|  | ret = get_anon_bdev(&pending_snapshot->anon_dev); | 
|  | if (ret < 0) | 
|  | goto free_pending; | 
|  | 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; | 
|  | } | 
|  |  | 
|  | block_rsv = &pending_snapshot->block_rsv; | 
|  | btrfs_init_block_rsv(block_rsv, BTRFS_BLOCK_RSV_TEMP); | 
|  | /* | 
|  | * 1 to add dir item | 
|  | * 1 to add dir index | 
|  | * 1 to update parent inode item | 
|  | */ | 
|  | trans_num_items = create_subvol_num_items(inherit) + 3; | 
|  | ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, block_rsv, | 
|  | trans_num_items, false); | 
|  | if (ret) | 
|  | goto free_pending; | 
|  | qgroup_reserved = block_rsv->qgroup_rsv_reserved; | 
|  |  | 
|  | pending_snapshot->dentry = dentry; | 
|  | pending_snapshot->root = root; | 
|  | pending_snapshot->readonly = readonly; | 
|  | pending_snapshot->dir = BTRFS_I(dir); | 
|  | pending_snapshot->inherit = inherit; | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 0); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto fail; | 
|  | } | 
|  | ret = btrfs_record_root_in_trans(trans, BTRFS_I(dir)->root); | 
|  | if (ret) { | 
|  | btrfs_end_transaction(trans); | 
|  | goto fail; | 
|  | } | 
|  | btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved); | 
|  | qgroup_reserved = 0; | 
|  |  | 
|  | trans->pending_snapshot = pending_snapshot; | 
|  |  | 
|  | ret = btrfs_commit_transaction(trans); | 
|  | if (ret) | 
|  | goto fail; | 
|  |  | 
|  | ret = pending_snapshot->error; | 
|  | if (ret) | 
|  | goto fail; | 
|  |  | 
|  | ret = btrfs_orphan_cleanup(pending_snapshot->snap); | 
|  | if (ret) | 
|  | goto fail; | 
|  |  | 
|  | inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry); | 
|  | if (IS_ERR(inode)) { | 
|  | ret = PTR_ERR(inode); | 
|  | goto fail; | 
|  | } | 
|  |  | 
|  | d_instantiate(dentry, inode); | 
|  | ret = 0; | 
|  | pending_snapshot->anon_dev = 0; | 
|  | fail: | 
|  | /* Prevent double freeing of anon_dev */ | 
|  | if (ret && pending_snapshot->snap) | 
|  | pending_snapshot->snap->anon_dev = 0; | 
|  | btrfs_put_root(pending_snapshot->snap); | 
|  | btrfs_block_rsv_release(fs_info, block_rsv, (u64)-1, NULL); | 
|  | if (qgroup_reserved) | 
|  | btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved); | 
|  | free_pending: | 
|  | if (pending_snapshot->anon_dev) | 
|  | free_anon_bdev(pending_snapshot->anon_dev); | 
|  | kfree(pending_snapshot->root_item); | 
|  | btrfs_free_path(pending_snapshot->path); | 
|  | 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 mnt_idmap *idmap, | 
|  | struct inode *dir, struct dentry *victim, int isdir) | 
|  | { | 
|  | int error; | 
|  |  | 
|  | if (d_really_is_negative(victim)) | 
|  | return -ENOENT; | 
|  |  | 
|  | /* The @victim is not inside @dir. */ | 
|  | if (d_inode(victim->d_parent) != dir) | 
|  | return -EINVAL; | 
|  | audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE); | 
|  |  | 
|  | error = inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC); | 
|  | if (error) | 
|  | return error; | 
|  | if (IS_APPEND(dir)) | 
|  | return -EPERM; | 
|  | if (check_sticky(idmap, 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 mnt_idmap *idmap, | 
|  | struct inode *dir, struct dentry *child) | 
|  | { | 
|  | if (d_really_is_positive(child)) | 
|  | return -EEXIST; | 
|  | if (IS_DEADDIR(dir)) | 
|  | return -ENOENT; | 
|  | if (!fsuidgid_has_mapping(dir->i_sb, idmap)) | 
|  | return -EOVERFLOW; | 
|  | return inode_permission(idmap, 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, | 
|  | struct mnt_idmap *idmap, | 
|  | const char *name, int namelen, | 
|  | struct btrfs_root *snap_src, | 
|  | bool readonly, | 
|  | struct btrfs_qgroup_inherit *inherit) | 
|  | { | 
|  | struct inode *dir = d_inode(parent->dentry); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); | 
|  | struct dentry *dentry; | 
|  | struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen); | 
|  | int error; | 
|  |  | 
|  | error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); | 
|  | if (error == -EINTR) | 
|  | return error; | 
|  |  | 
|  | dentry = lookup_one(idmap, name, parent->dentry, namelen); | 
|  | error = PTR_ERR(dentry); | 
|  | if (IS_ERR(dentry)) | 
|  | goto out_unlock; | 
|  |  | 
|  | error = btrfs_may_create(idmap, 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_str); | 
|  | 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, readonly, inherit); | 
|  | else | 
|  | error = create_subvol(idmap, dir, dentry, inherit); | 
|  |  | 
|  | if (!error) | 
|  | fsnotify_mkdir(dir, dentry); | 
|  | out_up_read: | 
|  | up_read(&fs_info->subvol_sem); | 
|  | out_dput: | 
|  | dput(dentry); | 
|  | out_unlock: | 
|  | btrfs_inode_unlock(BTRFS_I(dir), 0); | 
|  | return error; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_mksnapshot(const struct path *parent, | 
|  | struct mnt_idmap *idmap, | 
|  | const char *name, int namelen, | 
|  | struct btrfs_root *root, | 
|  | bool readonly, | 
|  | struct btrfs_qgroup_inherit *inherit) | 
|  | { | 
|  | int ret; | 
|  | bool snapshot_force_cow = false; | 
|  |  | 
|  | /* | 
|  | * 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. | 
|  | */ | 
|  | btrfs_drew_read_lock(&root->snapshot_lock); | 
|  |  | 
|  | ret = btrfs_start_delalloc_snapshot(root, false); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | /* | 
|  | * All previous writes have started writeback in NOCOW mode, so now | 
|  | * we force future writes to fallback to COW mode during snapshot | 
|  | * creation. | 
|  | */ | 
|  | atomic_inc(&root->snapshot_force_cow); | 
|  | snapshot_force_cow = true; | 
|  |  | 
|  | btrfs_wait_ordered_extents(root, U64_MAX, NULL); | 
|  |  | 
|  | ret = btrfs_mksubvol(parent, idmap, name, namelen, | 
|  | root, readonly, inherit); | 
|  | out: | 
|  | if (snapshot_force_cow) | 
|  | atomic_dec(&root->snapshot_force_cow); | 
|  | btrfs_drew_read_unlock(&root->snapshot_lock); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Try to start exclusive operation @type or cancel it if it's running. | 
|  | * | 
|  | * Return: | 
|  | *   0        - normal mode, newly claimed op started | 
|  | *  >0        - normal mode, something else is running, | 
|  | *              return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space | 
|  | * ECANCELED  - cancel mode, successful cancel | 
|  | * ENOTCONN   - cancel mode, operation not running anymore | 
|  | */ | 
|  | static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info, | 
|  | enum btrfs_exclusive_operation type, bool cancel) | 
|  | { | 
|  | if (!cancel) { | 
|  | /* Start normal op */ | 
|  | if (!btrfs_exclop_start(fs_info, type)) | 
|  | return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; | 
|  | /* Exclusive operation is now claimed */ | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* Cancel running op */ | 
|  | if (btrfs_exclop_start_try_lock(fs_info, type)) { | 
|  | /* | 
|  | * This blocks any exclop finish from setting it to NONE, so we | 
|  | * request cancellation. Either it runs and we will wait for it, | 
|  | * or it has finished and no waiting will happen. | 
|  | */ | 
|  | atomic_inc(&fs_info->reloc_cancel_req); | 
|  | btrfs_exclop_start_unlock(fs_info); | 
|  |  | 
|  | if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags)) | 
|  | wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING, | 
|  | TASK_INTERRUPTIBLE); | 
|  |  | 
|  | return -ECANCELED; | 
|  | } | 
|  |  | 
|  | /* Something else is running or none */ | 
|  | return -ENOTCONN; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_resize(struct file *file, | 
|  | void __user *arg) | 
|  | { | 
|  | BTRFS_DEV_LOOKUP_ARGS(args); | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | 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; | 
|  | bool cancel; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | /* | 
|  | * Read the arguments before checking exclusivity to be able to | 
|  | * distinguish regular resize and cancel | 
|  | */ | 
|  | vol_args = memdup_user(arg, sizeof(*vol_args)); | 
|  | if (IS_ERR(vol_args)) { | 
|  | ret = PTR_ERR(vol_args); | 
|  | goto out_drop; | 
|  | } | 
|  | ret = btrfs_check_ioctl_vol_args_path(vol_args); | 
|  | if (ret < 0) | 
|  | goto out_free; | 
|  |  | 
|  | sizestr = vol_args->name; | 
|  | cancel = (strcmp("cancel", sizestr) == 0); | 
|  | ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel); | 
|  | if (ret) | 
|  | goto out_free; | 
|  | /* Exclusive operation is now claimed */ | 
|  |  | 
|  | devstr = strchr(sizestr, ':'); | 
|  | if (devstr) { | 
|  | sizestr = devstr + 1; | 
|  | *devstr = '\0'; | 
|  | devstr = vol_args->name; | 
|  | ret = kstrtoull(devstr, 10, &devid); | 
|  | if (ret) | 
|  | goto out_finish; | 
|  | if (!devid) { | 
|  | ret = -EINVAL; | 
|  | goto out_finish; | 
|  | } | 
|  | btrfs_info(fs_info, "resizing devid %llu", devid); | 
|  | } | 
|  |  | 
|  | args.devid = devid; | 
|  | device = btrfs_find_device(fs_info->fs_devices, &args); | 
|  | if (!device) { | 
|  | btrfs_info(fs_info, "resizer unable to find device %llu", | 
|  | devid); | 
|  | ret = -ENODEV; | 
|  | goto out_finish; | 
|  | } | 
|  |  | 
|  | if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { | 
|  | btrfs_info(fs_info, | 
|  | "resizer unable to apply on readonly device %llu", | 
|  | devid); | 
|  | ret = -EPERM; | 
|  | goto out_finish; | 
|  | } | 
|  |  | 
|  | if (!strcmp(sizestr, "max")) | 
|  | new_size = bdev_nr_bytes(device->bdev); | 
|  | else { | 
|  | if (sizestr[0] == '-') { | 
|  | mod = -1; | 
|  | sizestr++; | 
|  | } else if (sizestr[0] == '+') { | 
|  | mod = 1; | 
|  | sizestr++; | 
|  | } | 
|  | new_size = memparse(sizestr, &retptr); | 
|  | if (*retptr != '\0' || new_size == 0) { | 
|  | ret = -EINVAL; | 
|  | goto out_finish; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { | 
|  | ret = -EPERM; | 
|  | goto out_finish; | 
|  | } | 
|  |  | 
|  | old_size = btrfs_device_get_total_bytes(device); | 
|  |  | 
|  | if (mod < 0) { | 
|  | if (new_size > old_size) { | 
|  | ret = -EINVAL; | 
|  | goto out_finish; | 
|  | } | 
|  | new_size = old_size - new_size; | 
|  | } else if (mod > 0) { | 
|  | if (new_size > ULLONG_MAX - old_size) { | 
|  | ret = -ERANGE; | 
|  | goto out_finish; | 
|  | } | 
|  | new_size = old_size + new_size; | 
|  | } | 
|  |  | 
|  | if (new_size < SZ_256M) { | 
|  | ret = -EINVAL; | 
|  | goto out_finish; | 
|  | } | 
|  | if (new_size > bdev_nr_bytes(device->bdev)) { | 
|  | ret = -EFBIG; | 
|  | goto out_finish; | 
|  | } | 
|  |  | 
|  | new_size = round_down(new_size, fs_info->sectorsize); | 
|  |  | 
|  | if (new_size > old_size) { | 
|  | trans = btrfs_start_transaction(root, 0); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_finish; | 
|  | } | 
|  | ret = btrfs_grow_device(trans, device, new_size); | 
|  | btrfs_commit_transaction(trans); | 
|  | } else if (new_size < old_size) { | 
|  | ret = btrfs_shrink_device(device, new_size); | 
|  | } /* equal, nothing need to do */ | 
|  |  | 
|  | if (ret == 0 && new_size != old_size) | 
|  | btrfs_info_in_rcu(fs_info, | 
|  | "resize device %s (devid %llu) from %llu to %llu", | 
|  | btrfs_dev_name(device), device->devid, | 
|  | old_size, new_size); | 
|  | out_finish: | 
|  | btrfs_exclop_finish(fs_info); | 
|  | out_free: | 
|  | kfree(vol_args); | 
|  | out_drop: | 
|  | mnt_drop_write_file(file); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static noinline int __btrfs_ioctl_snap_create(struct file *file, | 
|  | struct mnt_idmap *idmap, | 
|  | const char *name, unsigned long fd, int subvol, | 
|  | 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, idmap, name, | 
|  | namelen, NULL, readonly, inherit); | 
|  | } else { | 
|  | struct fd src = fdget(fd); | 
|  | struct inode *src_inode; | 
|  | if (!fd_file(src)) { | 
|  | ret = -EINVAL; | 
|  | goto out_drop_write; | 
|  | } | 
|  |  | 
|  | src_inode = file_inode(fd_file(src)); | 
|  | if (src_inode->i_sb != file_inode(file)->i_sb) { | 
|  | btrfs_info(BTRFS_I(file_inode(file))->root->fs_info, | 
|  | "Snapshot src from another FS"); | 
|  | ret = -EXDEV; | 
|  | } else if (!inode_owner_or_capable(idmap, src_inode)) { | 
|  | /* | 
|  | * Subvolume creation is not restricted, but snapshots | 
|  | * are limited to own subvolumes only | 
|  | */ | 
|  | ret = -EPERM; | 
|  | } else if (btrfs_ino(BTRFS_I(src_inode)) != BTRFS_FIRST_FREE_OBJECTID) { | 
|  | /* | 
|  | * Snapshots must be made with the src_inode referring | 
|  | * to the subvolume inode, otherwise the permission | 
|  | * checking above is useless because we may have | 
|  | * permission on a lower directory but not the subvol | 
|  | * itself. | 
|  | */ | 
|  | ret = -EINVAL; | 
|  | } else { | 
|  | ret = btrfs_mksnapshot(&file->f_path, idmap, | 
|  | name, namelen, | 
|  | BTRFS_I(src_inode)->root, | 
|  | 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); | 
|  | ret = btrfs_check_ioctl_vol_args_path(vol_args); | 
|  | if (ret < 0) | 
|  | goto out; | 
|  |  | 
|  | ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file), | 
|  | vol_args->name, vol_args->fd, subvol, | 
|  | false, NULL); | 
|  |  | 
|  | out: | 
|  | 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; | 
|  | 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); | 
|  | ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args); | 
|  | if (ret < 0) | 
|  | goto free_args; | 
|  |  | 
|  | if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto free_args; | 
|  | } | 
|  |  | 
|  | if (vol_args->flags & BTRFS_SUBVOL_RDONLY) | 
|  | readonly = true; | 
|  | if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) { | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file)); | 
|  |  | 
|  | if (vol_args->size < sizeof(*inherit) || | 
|  | vol_args->size > PAGE_SIZE) { | 
|  | 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; | 
|  | } | 
|  |  | 
|  | ret = btrfs_qgroup_check_inherit(fs_info, inherit, vol_args->size); | 
|  | if (ret < 0) | 
|  | goto free_inherit; | 
|  | } | 
|  |  | 
|  | ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file), | 
|  | vol_args->name, vol_args->fd, subvol, | 
|  | readonly, inherit); | 
|  | if (ret) | 
|  | goto free_inherit; | 
|  | free_inherit: | 
|  | kfree(inherit); | 
|  | free_args: | 
|  | kfree(vol_args); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode, | 
|  | void __user *arg) | 
|  | { | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | 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 = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_trans_handle *trans; | 
|  | u64 root_flags; | 
|  | u64 flags; | 
|  | int ret = 0; | 
|  |  | 
|  | if (!inode_owner_or_capable(file_mnt_idmap(file), 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_RDONLY) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto out_drop_write; | 
|  | } | 
|  |  | 
|  | down_write(&fs_info->subvol_sem); | 
|  |  | 
|  | /* nothing to do */ | 
|  | if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root)) | 
|  | goto out_drop_sem; | 
|  |  | 
|  | root_flags = btrfs_root_flags(&root->root_item); | 
|  | if (flags & BTRFS_SUBVOL_RDONLY) { | 
|  | btrfs_set_root_flags(&root->root_item, | 
|  | root_flags | BTRFS_ROOT_SUBVOL_RDONLY); | 
|  | } else { | 
|  | /* | 
|  | * Block RO -> RW transition if this subvolume is involved in | 
|  | * send | 
|  | */ | 
|  | spin_lock(&root->root_item_lock); | 
|  | if (root->send_in_progress == 0) { | 
|  | btrfs_set_root_flags(&root->root_item, | 
|  | root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY); | 
|  | spin_unlock(&root->root_item_lock); | 
|  | } else { | 
|  | spin_unlock(&root->root_item_lock); | 
|  | btrfs_warn(fs_info, | 
|  | "Attempt to set subvolume %llu read-write during send", | 
|  | btrfs_root_id(root)); | 
|  | ret = -EPERM; | 
|  | goto out_drop_sem; | 
|  | } | 
|  | } | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 1); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_reset; | 
|  | } | 
|  |  | 
|  | ret = btrfs_update_root(trans, fs_info->tree_root, | 
|  | &root->root_key, &root->root_item); | 
|  | if (ret < 0) { | 
|  | btrfs_end_transaction(trans); | 
|  | goto out_reset; | 
|  | } | 
|  |  | 
|  | ret = btrfs_commit_transaction(trans); | 
|  |  | 
|  | out_reset: | 
|  | if (ret) | 
|  | btrfs_set_root_flags(&root->root_item, root_flags); | 
|  | out_drop_sem: | 
|  | up_write(&fs_info->subvol_sem); | 
|  | out_drop_write: | 
|  | mnt_drop_write_file(file); | 
|  | 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, | 
|  | u64 *buf_size, | 
|  | char __user *ubuf, | 
|  | unsigned long *sk_offset, | 
|  | int *num_found) | 
|  | { | 
|  | u64 found_transid; | 
|  | struct extent_buffer *leaf; | 
|  | struct btrfs_ioctl_search_header sh; | 
|  | struct btrfs_key test; | 
|  | unsigned long item_off; | 
|  | unsigned long item_len; | 
|  | int nritems; | 
|  | int i; | 
|  | int slot; | 
|  | int ret = 0; | 
|  |  | 
|  | leaf = path->nodes[0]; | 
|  | slot = path->slots[0]; | 
|  | nritems = btrfs_header_nritems(leaf); | 
|  |  | 
|  | if (btrfs_header_generation(leaf) > sk->max_transid) { | 
|  | i = nritems; | 
|  | goto advance_key; | 
|  | } | 
|  | found_transid = btrfs_header_generation(leaf); | 
|  |  | 
|  | for (i = slot; i < nritems; i++) { | 
|  | item_off = btrfs_item_ptr_offset(leaf, i); | 
|  | item_len = btrfs_item_size(leaf, i); | 
|  |  | 
|  | btrfs_item_key_to_cpu(leaf, key, i); | 
|  | if (!key_in_sk(key, sk)) | 
|  | continue; | 
|  |  | 
|  | if (sizeof(sh) + item_len > *buf_size) { | 
|  | if (*num_found) { | 
|  | 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 (copy_to_user_nofault(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, | 
|  | u64 *buf_size, | 
|  | char __user *ubuf) | 
|  | { | 
|  | struct btrfs_fs_info *info = inode_to_fs_info(inode); | 
|  | 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_grab_root(BTRFS_I(inode)->root); | 
|  | } else { | 
|  | root = btrfs_get_fs_root(info, sk->tree_id, true); | 
|  | 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 = -EFAULT; | 
|  | /* | 
|  | * Ensure that the whole user buffer is faulted in at sub-page | 
|  | * granularity, otherwise the loop may live-lock. | 
|  | */ | 
|  | if (fault_in_subpage_writeable(ubuf + sk_offset, | 
|  | *buf_size - sk_offset)) | 
|  | 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_put_root(root); | 
|  | btrfs_free_path(path); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_tree_search(struct inode *inode, | 
|  | void __user *argp) | 
|  | { | 
|  | struct btrfs_ioctl_search_args __user *uargs = argp; | 
|  | struct btrfs_ioctl_search_key sk; | 
|  | int ret; | 
|  | u64 buf_size; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (copy_from_user(&sk, &uargs->key, sizeof(sk))) | 
|  | return -EFAULT; | 
|  |  | 
|  | buf_size = sizeof(uargs->buf); | 
|  |  | 
|  | ret = search_ioctl(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 inode *inode, | 
|  | void __user *argp) | 
|  | { | 
|  | struct btrfs_ioctl_search_args_v2 __user *uarg = argp; | 
|  | struct btrfs_ioctl_search_args_v2 args; | 
|  | int ret; | 
|  | u64 buf_size; | 
|  | const u64 buf_limit = SZ_16M; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | /* copy search header and buffer size */ | 
|  | if (copy_from_user(&args, uarg, sizeof(args))) | 
|  | return -EFAULT; | 
|  |  | 
|  | buf_size = args.buf_size; | 
|  |  | 
|  | /* limit result size to 16MB */ | 
|  | if (buf_size > buf_limit) | 
|  | buf_size = buf_limit; | 
|  |  | 
|  | ret = search_ioctl(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]; | 
|  |  | 
|  | root = btrfs_get_fs_root(info, tree_id, true); | 
|  | if (IS_ERR(root)) { | 
|  | ret = PTR_ERR(root); | 
|  | root = NULL; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | key.objectid = dirid; | 
|  | key.type = BTRFS_INODE_REF_KEY; | 
|  | key.offset = (u64)-1; | 
|  |  | 
|  | while (1) { | 
|  | ret = btrfs_search_backwards(root, &key, path); | 
|  | if (ret < 0) | 
|  | goto out; | 
|  | else if (ret > 0) { | 
|  | ret = -ENOENT; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | l = path->nodes[0]; | 
|  | slot = path->slots[0]; | 
|  |  | 
|  | iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref); | 
|  | len = btrfs_inode_ref_name_len(l, iref); | 
|  | ptr -= len + 1; | 
|  | total_len += len + 1; | 
|  | if (ptr < name) { | 
|  | 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_put_root(root); | 
|  | btrfs_free_path(path); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap, | 
|  | struct inode *inode, | 
|  | struct btrfs_ioctl_ino_lookup_user_args *args) | 
|  | { | 
|  | struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; | 
|  | u64 upper_limit = btrfs_ino(BTRFS_I(inode)); | 
|  | u64 treeid = btrfs_root_id(BTRFS_I(inode)->root); | 
|  | u64 dirid = args->dirid; | 
|  | unsigned long item_off; | 
|  | unsigned long item_len; | 
|  | struct btrfs_inode_ref *iref; | 
|  | struct btrfs_root_ref *rref; | 
|  | struct btrfs_root *root = NULL; | 
|  | 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) { | 
|  | ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1]; | 
|  |  | 
|  | root = btrfs_get_fs_root(fs_info, treeid, true); | 
|  | 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_backwards(root, &key, path); | 
|  | if (ret < 0) | 
|  | goto out_put; | 
|  | else if (ret > 0) { | 
|  | ret = -ENOENT; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | leaf = path->nodes[0]; | 
|  | slot = path->slots[0]; | 
|  |  | 
|  | iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref); | 
|  | len = btrfs_inode_ref_name_len(leaf, iref); | 
|  | ptr -= len + 1; | 
|  | total_len += len + 1; | 
|  | if (ptr < args->path) { | 
|  | ret = -ENAMETOOLONG; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | *(ptr + len) = '/'; | 
|  | read_extent_buffer(leaf, ptr, | 
|  | (unsigned long)(iref + 1), len); | 
|  |  | 
|  | /* Check the read+exec permission of this directory */ | 
|  | ret = btrfs_previous_item(root, path, dirid, | 
|  | BTRFS_INODE_ITEM_KEY); | 
|  | if (ret < 0) { | 
|  | goto out_put; | 
|  | } else if (ret > 0) { | 
|  | ret = -ENOENT; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | leaf = path->nodes[0]; | 
|  | slot = path->slots[0]; | 
|  | btrfs_item_key_to_cpu(leaf, &key2, slot); | 
|  | if (key2.objectid != dirid) { | 
|  | ret = -ENOENT; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * We don't need the path anymore, so release it and | 
|  | * avoid deadlocks and lockdep warnings in case | 
|  | * btrfs_iget() needs to lookup the inode from its root | 
|  | * btree and lock the same leaf. | 
|  | */ | 
|  | btrfs_release_path(path); | 
|  | temp_inode = btrfs_iget(key2.objectid, root); | 
|  | if (IS_ERR(temp_inode)) { | 
|  | ret = PTR_ERR(temp_inode); | 
|  | goto out_put; | 
|  | } | 
|  | ret = inode_permission(idmap, temp_inode, | 
|  | MAY_READ | MAY_EXEC); | 
|  | iput(temp_inode); | 
|  | if (ret) { | 
|  | ret = -EACCES; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | if (key.offset == upper_limit) | 
|  | break; | 
|  | if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) { | 
|  | ret = -EACCES; | 
|  | goto out_put; | 
|  | } | 
|  |  | 
|  | key.objectid = key.offset; | 
|  | key.offset = (u64)-1; | 
|  | dirid = key.objectid; | 
|  | } | 
|  |  | 
|  | memmove(args->path, ptr, total_len); | 
|  | args->path[total_len] = '\0'; | 
|  | btrfs_put_root(root); | 
|  | root = NULL; | 
|  | btrfs_release_path(path); | 
|  | } | 
|  |  | 
|  | /* Get the bottom subvolume's name from ROOT_REF */ | 
|  | key.objectid = treeid; | 
|  | key.type = BTRFS_ROOT_REF_KEY; | 
|  | key.offset = args->treeid; | 
|  | ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); | 
|  | if (ret < 0) { | 
|  | 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(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_put: | 
|  | btrfs_put_root(root); | 
|  | out: | 
|  | btrfs_free_path(path); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root, | 
|  | void __user *argp) | 
|  | { | 
|  | struct btrfs_ioctl_ino_lookup_args *args; | 
|  | int ret = 0; | 
|  |  | 
|  | args = memdup_user(argp, sizeof(*args)); | 
|  | if (IS_ERR(args)) | 
|  | return PTR_ERR(args); | 
|  |  | 
|  | /* | 
|  | * Unprivileged query to obtain the containing subvolume root id. The | 
|  | * path is reset so it's consistent with btrfs_search_path_in_tree. | 
|  | */ | 
|  | if (args->treeid == 0) | 
|  | args->treeid = btrfs_root_id(root); | 
|  |  | 
|  | 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(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_ino(BTRFS_I(inode)) != 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(file_mnt_idmap(file), 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 inode *inode, 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; | 
|  | 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; | 
|  | } | 
|  |  | 
|  | fs_info = BTRFS_I(inode)->root->fs_info; | 
|  |  | 
|  | /* Get root_item of inode's subvolume */ | 
|  | key.objectid = btrfs_root_id(BTRFS_I(inode)->root); | 
|  | root = btrfs_get_fs_root(fs_info, key.objectid, true); | 
|  | if (IS_ERR(root)) { | 
|  | ret = PTR_ERR(root); | 
|  | goto out_free; | 
|  | } | 
|  | root_item = &root->root_item; | 
|  |  | 
|  | subvol_info->treeid = key.objectid; | 
|  |  | 
|  | subvol_info->generation = btrfs_root_generation(root_item); | 
|  | subvol_info->flags = btrfs_root_flags(root_item); | 
|  |  | 
|  | memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE); | 
|  | memcpy(subvol_info->parent_uuid, root_item->parent_uuid, | 
|  | BTRFS_UUID_SIZE); | 
|  | memcpy(subvol_info->received_uuid, root_item->received_uuid, | 
|  | BTRFS_UUID_SIZE); | 
|  |  | 
|  | subvol_info->ctransid = btrfs_root_ctransid(root_item); | 
|  | subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime); | 
|  | subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime); | 
|  |  | 
|  | subvol_info->otransid = btrfs_root_otransid(root_item); | 
|  | subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime); | 
|  | subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime); | 
|  |  | 
|  | subvol_info->stransid = btrfs_root_stransid(root_item); | 
|  | subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime); | 
|  | subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime); | 
|  |  | 
|  | subvol_info->rtransid = btrfs_root_rtransid(root_item); | 
|  | subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime); | 
|  | subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime); | 
|  |  | 
|  | if (key.objectid != BTRFS_FS_TREE_OBJECTID) { | 
|  | /* Search root tree for ROOT_BACKREF of this subvolume */ | 
|  | key.type = BTRFS_ROOT_BACKREF_KEY; | 
|  | key.offset = 0; | 
|  | ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0); | 
|  | if (ret < 0) { | 
|  | goto out; | 
|  | } else if (path->slots[0] >= | 
|  | btrfs_header_nritems(path->nodes[0])) { | 
|  | ret = btrfs_next_leaf(fs_info->tree_root, path); | 
|  | if (ret < 0) { | 
|  | goto out; | 
|  | } else if (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(leaf, slot) | 
|  | - sizeof(struct btrfs_root_ref); | 
|  | read_extent_buffer(leaf, subvol_info->name, | 
|  | item_off, item_len); | 
|  | } else { | 
|  | ret = -ENOENT; | 
|  | goto out; | 
|  | } | 
|  | } | 
|  |  | 
|  | btrfs_free_path(path); | 
|  | path = NULL; | 
|  | if (copy_to_user(argp, subvol_info, sizeof(*subvol_info))) | 
|  | ret = -EFAULT; | 
|  |  | 
|  | out: | 
|  | btrfs_put_root(root); | 
|  | out_free: | 
|  | btrfs_free_path(path); | 
|  | kfree(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 btrfs_root *root, | 
|  | void __user *argp) | 
|  | { | 
|  | struct btrfs_ioctl_get_subvol_rootref_args *rootrefs; | 
|  | struct btrfs_root_ref *rref; | 
|  | struct btrfs_path *path; | 
|  | struct btrfs_key key; | 
|  | struct extent_buffer *leaf; | 
|  | u64 objectid; | 
|  | int slot; | 
|  | int ret; | 
|  | u8 found; | 
|  |  | 
|  | path = btrfs_alloc_path(); | 
|  | if (!path) | 
|  | return -ENOMEM; | 
|  |  | 
|  | rootrefs = memdup_user(argp, sizeof(*rootrefs)); | 
|  | if (IS_ERR(rootrefs)) { | 
|  | btrfs_free_path(path); | 
|  | return PTR_ERR(rootrefs); | 
|  | } | 
|  |  | 
|  | objectid = btrfs_root_id(root); | 
|  | key.objectid = objectid; | 
|  | key.type = BTRFS_ROOT_REF_KEY; | 
|  | key.offset = rootrefs->min_treeid; | 
|  | found = 0; | 
|  |  | 
|  | root = root->fs_info->tree_root; | 
|  | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | 
|  | if (ret < 0) { | 
|  | goto out; | 
|  | } else if (path->slots[0] >= | 
|  | btrfs_header_nritems(path->nodes[0])) { | 
|  | ret = btrfs_next_leaf(root, path); | 
|  | if (ret < 0) { | 
|  | goto out; | 
|  | } else if (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: | 
|  | btrfs_free_path(path); | 
|  |  | 
|  | if (!ret || ret == -EOVERFLOW) { | 
|  | rootrefs->num_items = found; | 
|  | /* update min_treeid for next search */ | 
|  | if (found) | 
|  | rootrefs->min_treeid = | 
|  | rootrefs->rootref[found - 1].treeid + 1; | 
|  | if (copy_to_user(argp, rootrefs, sizeof(*rootrefs))) | 
|  | ret = -EFAULT; | 
|  | } | 
|  |  | 
|  | kfree(rootrefs); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static noinline int btrfs_ioctl_snap_destroy(struct file *file, | 
|  | void __user *arg, | 
|  | bool destroy_v2) | 
|  | { | 
|  | struct dentry *parent = file->f_path.dentry; | 
|  | struct dentry *dentry; | 
|  | struct inode *dir = d_inode(parent); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(dir); | 
|  | struct inode *inode; | 
|  | struct btrfs_root *root = BTRFS_I(dir)->root; | 
|  | struct btrfs_root *dest = NULL; | 
|  | struct btrfs_ioctl_vol_args *vol_args = NULL; | 
|  | struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL; | 
|  | struct mnt_idmap *idmap = file_mnt_idmap(file); | 
|  | char *subvol_name, *subvol_name_ptr = NULL; | 
|  | int subvol_namelen; | 
|  | int ret = 0; | 
|  | bool destroy_parent = false; | 
|  |  | 
|  | /* We don't support snapshots with extent tree v2 yet. */ | 
|  | if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { | 
|  | btrfs_err(fs_info, | 
|  | "extent tree v2 doesn't support snapshot deletion yet"); | 
|  | return -EOPNOTSUPP; | 
|  | } | 
|  |  | 
|  | if (destroy_v2) { | 
|  | vol_args2 = memdup_user(arg, sizeof(*vol_args2)); | 
|  | if (IS_ERR(vol_args2)) | 
|  | return PTR_ERR(vol_args2); | 
|  |  | 
|  | if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * If SPEC_BY_ID is not set, we are looking for the subvolume by | 
|  | * name, same as v1 currently does. | 
|  | */ | 
|  | if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) { | 
|  | ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args2); | 
|  | if (ret < 0) | 
|  | goto out; | 
|  | subvol_name = vol_args2->name; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | goto out; | 
|  | } else { | 
|  | struct inode *old_dir; | 
|  |  | 
|  | if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) { | 
|  | ret = -EINVAL; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | dentry = btrfs_get_dentry(fs_info->sb, | 
|  | BTRFS_FIRST_FREE_OBJECTID, | 
|  | vol_args2->subvolid, 0); | 
|  | if (IS_ERR(dentry)) { | 
|  | ret = PTR_ERR(dentry); | 
|  | goto out_drop_write; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Change the default parent since the subvolume being | 
|  | * deleted can be outside of the current mount point. | 
|  | */ | 
|  | parent = btrfs_get_parent(dentry); | 
|  |  | 
|  | /* | 
|  | * At this point dentry->d_name can point to '/' if the | 
|  | * subvolume we want to destroy is outsite of the | 
|  | * current mount point, so we need to release the | 
|  | * current dentry and execute the lookup to return a new | 
|  | * one with ->d_name pointing to the | 
|  | * <mount point>/subvol_name. | 
|  | */ | 
|  | dput(dentry); | 
|  | if (IS_ERR(parent)) { | 
|  | ret = PTR_ERR(parent); | 
|  | goto out_drop_write; | 
|  | } | 
|  | old_dir = dir; | 
|  | dir = d_inode(parent); | 
|  |  | 
|  | /* | 
|  | * If v2 was used with SPEC_BY_ID, a new parent was | 
|  | * allocated since the subvolume can be outside of the | 
|  | * current mount point. Later on we need to release this | 
|  | * new parent dentry. | 
|  | */ | 
|  | destroy_parent = true; | 
|  |  | 
|  | /* | 
|  | * On idmapped mounts, deletion via subvolid is | 
|  | * restricted to subvolumes that are immediate | 
|  | * ancestors of the inode referenced by the file | 
|  | * descriptor in the ioctl. Otherwise the idmapping | 
|  | * could potentially be abused to delete subvolumes | 
|  | * anywhere in the filesystem the user wouldn't be able | 
|  | * to delete without an idmapped mount. | 
|  | */ | 
|  | if (old_dir != dir && idmap != &nop_mnt_idmap) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto free_parent; | 
|  | } | 
|  |  | 
|  | subvol_name_ptr = btrfs_get_subvol_name_from_objectid( | 
|  | fs_info, vol_args2->subvolid); | 
|  | if (IS_ERR(subvol_name_ptr)) { | 
|  | ret = PTR_ERR(subvol_name_ptr); | 
|  | goto free_parent; | 
|  | } | 
|  | /* subvol_name_ptr is already nul terminated */ | 
|  | subvol_name = (char *)kbasename(subvol_name_ptr); | 
|  | } | 
|  | } else { | 
|  | vol_args = memdup_user(arg, sizeof(*vol_args)); | 
|  | if (IS_ERR(vol_args)) | 
|  | return PTR_ERR(vol_args); | 
|  |  | 
|  | ret = btrfs_check_ioctl_vol_args_path(vol_args); | 
|  | if (ret < 0) | 
|  | goto out; | 
|  |  | 
|  | subvol_name = vol_args->name; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | subvol_namelen = strlen(subvol_name); | 
|  |  | 
|  | if (strchr(subvol_name, '/') || | 
|  | strncmp(subvol_name, "..", subvol_namelen) == 0) { | 
|  | ret = -EINVAL; | 
|  | goto free_subvol_name; | 
|  | } | 
|  |  | 
|  | if (!S_ISDIR(dir->i_mode)) { | 
|  | ret = -ENOTDIR; | 
|  | goto free_subvol_name; | 
|  | } | 
|  |  | 
|  | ret = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT); | 
|  | if (ret == -EINTR) | 
|  | goto free_subvol_name; | 
|  | dentry = lookup_one(idmap, subvol_name, parent, subvol_namelen); | 
|  | if (IS_ERR(dentry)) { | 
|  | ret = PTR_ERR(dentry); | 
|  | goto out_unlock_dir; | 
|  | } | 
|  |  | 
|  | if (d_really_is_negative(dentry)) { | 
|  | ret = -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). | 
|  | */ | 
|  | ret = -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. | 
|  | */ | 
|  | ret = -EINVAL; | 
|  | if (root == dest) | 
|  | goto out_dput; | 
|  |  | 
|  | ret = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC); | 
|  | if (ret) | 
|  | goto out_dput; | 
|  | } | 
|  |  | 
|  | /* check if subvolume may be deleted by a user */ | 
|  | ret = btrfs_may_delete(idmap, dir, dentry, 1); | 
|  | if (ret) | 
|  | goto out_dput; | 
|  |  | 
|  | if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { | 
|  | ret = -EINVAL; | 
|  | goto out_dput; | 
|  | } | 
|  |  | 
|  | btrfs_inode_lock(BTRFS_I(inode), 0); | 
|  | ret = btrfs_delete_subvolume(BTRFS_I(dir), dentry); | 
|  | btrfs_inode_unlock(BTRFS_I(inode), 0); | 
|  | if (!ret) | 
|  | d_delete_notify(dir, dentry); | 
|  |  | 
|  | out_dput: | 
|  | dput(dentry); | 
|  | out_unlock_dir: | 
|  | btrfs_inode_unlock(BTRFS_I(dir), 0); | 
|  | free_subvol_name: | 
|  | kfree(subvol_name_ptr); | 
|  | free_parent: | 
|  | if (destroy_parent) | 
|  | dput(parent); | 
|  | out_drop_write: | 
|  | mnt_drop_write_file(file); | 
|  | out: | 
|  | kfree(vol_args2); | 
|  | kfree(vol_args); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int btrfs_ioctl_defrag(struct file *file, void __user *argp) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_ioctl_defrag_range_args range = {0}; | 
|  | int ret; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | if (btrfs_root_readonly(root)) { | 
|  | ret = -EROFS; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | switch (inode->i_mode & S_IFMT) { | 
|  | case S_IFDIR: | 
|  | if (!capable(CAP_SYS_ADMIN)) { | 
|  | ret = -EPERM; | 
|  | goto out; | 
|  | } | 
|  | ret = btrfs_defrag_root(root); | 
|  | break; | 
|  | case S_IFREG: | 
|  | /* | 
|  | * Note that this does not check the file descriptor for write | 
|  | * access. This prevents defragmenting executables that are | 
|  | * running and allows defrag on files open in read-only mode. | 
|  | */ | 
|  | if (!capable(CAP_SYS_ADMIN) && | 
|  | inode_permission(&nop_mnt_idmap, inode, MAY_WRITE)) { | 
|  | ret = -EPERM; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if (argp) { | 
|  | if (copy_from_user(&range, argp, sizeof(range))) { | 
|  | ret = -EFAULT; | 
|  | goto out; | 
|  | } | 
|  | if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto out; | 
|  | } | 
|  | /* 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->f_ra, | 
|  | &range, BTRFS_OLDEST_GENERATION, 0); | 
|  | if (ret > 0) | 
|  | ret = 0; | 
|  | break; | 
|  | default: | 
|  | ret = -EINVAL; | 
|  | } | 
|  | out: | 
|  | mnt_drop_write_file(file); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg) | 
|  | { | 
|  | struct btrfs_ioctl_vol_args *vol_args; | 
|  | bool restore_op = false; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { | 
|  | btrfs_err(fs_info, "device add not supported on extent tree v2 yet"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (fs_info->fs_devices->temp_fsid) { | 
|  | btrfs_err(fs_info, | 
|  | "device add not supported on cloned temp-fsid mount"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) { | 
|  | if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD)) | 
|  | return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; | 
|  |  | 
|  | /* | 
|  | * We can do the device add because we have a paused balanced, | 
|  | * change the exclusive op type and remember we should bring | 
|  | * back the paused balance | 
|  | */ | 
|  | fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD; | 
|  | btrfs_exclop_start_unlock(fs_info); | 
|  | restore_op = true; | 
|  | } | 
|  |  | 
|  | vol_args = memdup_user(arg, sizeof(*vol_args)); | 
|  | if (IS_ERR(vol_args)) { | 
|  | ret = PTR_ERR(vol_args); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = btrfs_check_ioctl_vol_args_path(vol_args); | 
|  | if (ret < 0) | 
|  | goto out_free; | 
|  |  | 
|  | ret = btrfs_init_new_device(fs_info, vol_args->name); | 
|  |  | 
|  | if (!ret) | 
|  | btrfs_info(fs_info, "disk added %s", vol_args->name); | 
|  |  | 
|  | out_free: | 
|  | kfree(vol_args); | 
|  | out: | 
|  | if (restore_op) | 
|  | btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED); | 
|  | else | 
|  | btrfs_exclop_finish(fs_info); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg) | 
|  | { | 
|  | BTRFS_DEV_LOOKUP_ARGS(args); | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_ioctl_vol_args_v2 *vol_args; | 
|  | struct file *bdev_file = NULL; | 
|  | int ret; | 
|  | bool cancel = false; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | vol_args = memdup_user(arg, sizeof(*vol_args)); | 
|  | if (IS_ERR(vol_args)) | 
|  | return PTR_ERR(vol_args); | 
|  |  | 
|  | if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args); | 
|  | if (ret < 0) | 
|  | goto out; | 
|  |  | 
|  | if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) { | 
|  | args.devid = vol_args->devid; | 
|  | } else if (!strcmp("cancel", vol_args->name)) { | 
|  | cancel = true; | 
|  | } else { | 
|  | ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name); | 
|  | if (ret) | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE, | 
|  | cancel); | 
|  | if (ret) | 
|  | goto err_drop; | 
|  |  | 
|  | /* Exclusive operation is now claimed */ | 
|  | ret = btrfs_rm_device(fs_info, &args, &bdev_file); | 
|  |  | 
|  | btrfs_exclop_finish(fs_info); | 
|  |  | 
|  | if (!ret) { | 
|  | if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) | 
|  | btrfs_info(fs_info, "device deleted: id %llu", | 
|  | vol_args->devid); | 
|  | else | 
|  | btrfs_info(fs_info, "device deleted: %s", | 
|  | vol_args->name); | 
|  | } | 
|  | err_drop: | 
|  | mnt_drop_write_file(file); | 
|  | if (bdev_file) | 
|  | fput(bdev_file); | 
|  | out: | 
|  | btrfs_put_dev_args_from_path(&args); | 
|  | kfree(vol_args); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg) | 
|  | { | 
|  | BTRFS_DEV_LOOKUP_ARGS(args); | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_ioctl_vol_args *vol_args; | 
|  | struct file *bdev_file = NULL; | 
|  | int ret; | 
|  | bool cancel = false; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | vol_args = memdup_user(arg, sizeof(*vol_args)); | 
|  | if (IS_ERR(vol_args)) | 
|  | return PTR_ERR(vol_args); | 
|  |  | 
|  | ret = btrfs_check_ioctl_vol_args_path(vol_args); | 
|  | if (ret < 0) | 
|  | goto out_free; | 
|  |  | 
|  | if (!strcmp("cancel", vol_args->name)) { | 
|  | cancel = true; | 
|  | } else { | 
|  | ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name); | 
|  | if (ret) | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE, | 
|  | cancel); | 
|  | if (ret == 0) { | 
|  | ret = btrfs_rm_device(fs_info, &args, &bdev_file); | 
|  | if (!ret) | 
|  | btrfs_info(fs_info, "disk deleted %s", vol_args->name); | 
|  | btrfs_exclop_finish(fs_info); | 
|  | } | 
|  |  | 
|  | mnt_drop_write_file(file); | 
|  | if (bdev_file) | 
|  | fput(bdev_file); | 
|  | out: | 
|  | btrfs_put_dev_args_from_path(&args); | 
|  | out_free: | 
|  | kfree(vol_args); | 
|  | 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; | 
|  | u64 flags_in; | 
|  | int ret = 0; | 
|  |  | 
|  | fi_args = memdup_user(arg, sizeof(*fi_args)); | 
|  | if (IS_ERR(fi_args)) | 
|  | return PTR_ERR(fi_args); | 
|  |  | 
|  | flags_in = fi_args->flags; | 
|  | memset(fi_args, 0, sizeof(*fi_args)); | 
|  |  | 
|  | rcu_read_lock(); | 
|  | fi_args->num_devices = fs_devices->num_devices; | 
|  |  | 
|  | list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { | 
|  | if (device->devid > fi_args->max_id) | 
|  | fi_args->max_id = device->devid; | 
|  | } | 
|  | rcu_read_unlock(); | 
|  |  | 
|  | memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid)); | 
|  | fi_args->nodesize = fs_info->nodesize; | 
|  | fi_args->sectorsize = fs_info->sectorsize; | 
|  | fi_args->clone_alignment = fs_info->sectorsize; | 
|  |  | 
|  | if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) { | 
|  | fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy); | 
|  | fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy); | 
|  | fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO; | 
|  | } | 
|  |  | 
|  | if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) { | 
|  | fi_args->generation = btrfs_get_fs_generation(fs_info); | 
|  | fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION; | 
|  | } | 
|  |  | 
|  | if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) { | 
|  | memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid, | 
|  | sizeof(fi_args->metadata_uuid)); | 
|  | fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID; | 
|  | } | 
|  |  | 
|  | if (copy_to_user(arg, fi_args, sizeof(*fi_args))) | 
|  | ret = -EFAULT; | 
|  |  | 
|  | kfree(fi_args); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | BTRFS_DEV_LOOKUP_ARGS(args); | 
|  | struct btrfs_ioctl_dev_info_args *di_args; | 
|  | struct btrfs_device *dev; | 
|  | int ret = 0; | 
|  |  | 
|  | di_args = memdup_user(arg, sizeof(*di_args)); | 
|  | if (IS_ERR(di_args)) | 
|  | return PTR_ERR(di_args); | 
|  |  | 
|  | args.devid = di_args->devid; | 
|  | if (!btrfs_is_empty_uuid(di_args->uuid)) | 
|  | args.uuid = di_args->uuid; | 
|  |  | 
|  | rcu_read_lock(); | 
|  | dev = btrfs_find_device(fs_info->fs_devices, &args); | 
|  | if (!dev) { | 
|  | ret = -ENODEV; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | di_args->devid = dev->devid; | 
|  | di_args->bytes_used = btrfs_device_get_bytes_used(dev); | 
|  | di_args->total_bytes = btrfs_device_get_total_bytes(dev); | 
|  | memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid)); | 
|  | memcpy(di_args->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE); | 
|  | if (dev->name) | 
|  | strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path)); | 
|  | else | 
|  | di_args->path[0] = '\0'; | 
|  |  | 
|  | out: | 
|  | rcu_read_unlock(); | 
|  | if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args))) | 
|  | ret = -EFAULT; | 
|  |  | 
|  | kfree(di_args); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_root *new_root; | 
|  | struct btrfs_dir_item *di; | 
|  | struct btrfs_trans_handle *trans; | 
|  | struct btrfs_path *path = NULL; | 
|  | struct btrfs_disk_key disk_key; | 
|  | struct fscrypt_str name = FSTR_INIT("default", 7); | 
|  | u64 objectid = 0; | 
|  | u64 dir_id; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | if (copy_from_user(&objectid, argp, sizeof(objectid))) { | 
|  | ret = -EFAULT; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if (!objectid) | 
|  | objectid = BTRFS_FS_TREE_OBJECTID; | 
|  |  | 
|  | new_root = btrfs_get_fs_root(fs_info, objectid, true); | 
|  | if (IS_ERR(new_root)) { | 
|  | ret = PTR_ERR(new_root); | 
|  | goto out; | 
|  | } | 
|  | if (!is_fstree(btrfs_root_id(new_root))) { | 
|  | ret = -ENOENT; | 
|  | goto out_free; | 
|  | } | 
|  |  | 
|  | path = btrfs_alloc_path(); | 
|  | if (!path) { | 
|  | ret = -ENOMEM; | 
|  | goto out_free; | 
|  | } | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 1); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_free; | 
|  | } | 
|  |  | 
|  | dir_id = btrfs_super_root_dir(fs_info->super_copy); | 
|  | di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path, | 
|  | dir_id, &name, 1); | 
|  | if (IS_ERR_OR_NULL(di)) { | 
|  | btrfs_release_path(path); | 
|  | btrfs_end_transaction(trans); | 
|  | btrfs_err(fs_info, | 
|  | "Umm, you don't have the default diritem, this isn't going to work"); | 
|  | ret = -ENOENT; | 
|  | goto out_free; | 
|  | } | 
|  |  | 
|  | btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key); | 
|  | btrfs_set_dir_item_key(path->nodes[0], di, &disk_key); | 
|  | btrfs_mark_buffer_dirty(trans, path->nodes[0]); | 
|  | btrfs_release_path(path); | 
|  |  | 
|  | btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL); | 
|  | btrfs_end_transaction(trans); | 
|  | out_free: | 
|  | btrfs_put_root(new_root); | 
|  | btrfs_free_path(path); | 
|  | out: | 
|  | mnt_drop_write_file(file); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void get_block_group_info(struct list_head *groups_list, | 
|  | struct btrfs_ioctl_space_info *space) | 
|  | { | 
|  | struct btrfs_block_group *block_group; | 
|  |  | 
|  | space->total_bytes = 0; | 
|  | space->used_bytes = 0; | 
|  | space->flags = 0; | 
|  | list_for_each_entry(block_group, groups_list, list) { | 
|  | space->flags = block_group->flags; | 
|  | space->total_bytes += block_group->length; | 
|  | space->used_bytes += block_group->used; | 
|  | } | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | struct btrfs_ioctl_space_args space_args = { 0 }; | 
|  | struct btrfs_ioctl_space_info space; | 
|  | struct btrfs_ioctl_space_info *dest; | 
|  | struct btrfs_ioctl_space_info *dest_orig; | 
|  | struct btrfs_ioctl_space_info __user *user_dest; | 
|  | struct btrfs_space_info *info; | 
|  | static const u64 types[] = { | 
|  | BTRFS_BLOCK_GROUP_DATA, | 
|  | BTRFS_BLOCK_GROUP_SYSTEM, | 
|  | BTRFS_BLOCK_GROUP_METADATA, | 
|  | BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA | 
|  | }; | 
|  | int num_types = 4; | 
|  | int alloc_size; | 
|  | int ret = 0; | 
|  | u64 slot_count = 0; | 
|  | int i, c; | 
|  |  | 
|  | if (copy_from_user(&space_args, | 
|  | (struct btrfs_ioctl_space_args __user *)arg, | 
|  | sizeof(space_args))) | 
|  | return -EFAULT; | 
|  |  | 
|  | for (i = 0; i < num_types; i++) { | 
|  | struct btrfs_space_info *tmp; | 
|  |  | 
|  | info = NULL; | 
|  | list_for_each_entry(tmp, &fs_info->space_info, list) { | 
|  | if (tmp->flags == types[i]) { | 
|  | info = tmp; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!info) | 
|  | continue; | 
|  |  | 
|  | down_read(&info->groups_sem); | 
|  | for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { | 
|  | if (!list_empty(&info->block_groups[c])) | 
|  | slot_count++; | 
|  | } | 
|  | up_read(&info->groups_sem); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Global block reserve, exported as a space_info | 
|  | */ | 
|  | slot_count++; | 
|  |  | 
|  | /* space_slots == 0 means they are asking for a count */ | 
|  | if (space_args.space_slots == 0) { | 
|  | space_args.total_spaces = slot_count; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | slot_count = min_t(u64, space_args.space_slots, slot_count); | 
|  |  | 
|  | alloc_size = sizeof(*dest) * slot_count; | 
|  |  | 
|  | /* we generally have at most 6 or so space infos, one for each raid | 
|  | * level.  So, a whole page should be more than enough for everyone | 
|  | */ | 
|  | if (alloc_size > PAGE_SIZE) | 
|  | return -ENOMEM; | 
|  |  | 
|  | space_args.total_spaces = 0; | 
|  | dest = 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; | 
|  | list_for_each_entry(tmp, &fs_info->space_info, list) { | 
|  | if (tmp->flags == types[i]) { | 
|  | info = tmp; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (!info) | 
|  | continue; | 
|  | down_read(&info->groups_sem); | 
|  | for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) { | 
|  | if (!list_empty(&info->block_groups[c])) { | 
|  | get_block_group_info(&info->block_groups[c], | 
|  | &space); | 
|  | memcpy(dest, &space, sizeof(space)); | 
|  | dest++; | 
|  | space_args.total_spaces++; | 
|  | slot_count--; | 
|  | } | 
|  | if (!slot_count) | 
|  | break; | 
|  | } | 
|  | up_read(&info->groups_sem); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Add global block reserve | 
|  | */ | 
|  | if (slot_count) { | 
|  | struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; | 
|  |  | 
|  | spin_lock(&block_rsv->lock); | 
|  | space.total_bytes = block_rsv->size; | 
|  | space.used_bytes = block_rsv->size - block_rsv->reserved; | 
|  | spin_unlock(&block_rsv->lock); | 
|  | space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; | 
|  | memcpy(dest, &space, sizeof(space)); | 
|  | space_args.total_spaces++; | 
|  | } | 
|  |  | 
|  | user_dest = (struct btrfs_ioctl_space_info __user *) | 
|  | (arg + sizeof(struct btrfs_ioctl_space_args)); | 
|  |  | 
|  | if (copy_to_user(user_dest, dest_orig, 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; | 
|  |  | 
|  | /* | 
|  | * Start orphan cleanup here for the given root in case it hasn't been | 
|  | * started already by other means. Errors are handled in the other | 
|  | * functions during transaction commit. | 
|  | */ | 
|  | btrfs_orphan_cleanup(root); | 
|  |  | 
|  | trans = btrfs_attach_transaction_barrier(root); | 
|  | if (IS_ERR(trans)) { | 
|  | if (PTR_ERR(trans) != -ENOENT) | 
|  | return PTR_ERR(trans); | 
|  |  | 
|  | /* No running transaction, don't bother */ | 
|  | transid = btrfs_get_last_trans_committed(root->fs_info); | 
|  | goto out; | 
|  | } | 
|  | transid = trans->transid; | 
|  | btrfs_commit_transaction_async(trans); | 
|  | out: | 
|  | if (argp) | 
|  | if (copy_to_user(argp, &transid, sizeof(transid))) | 
|  | return -EFAULT; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info, | 
|  | void __user *argp) | 
|  | { | 
|  | /* By default wait for the current transaction. */ | 
|  | u64 transid = 0; | 
|  |  | 
|  | if (argp) | 
|  | if (copy_from_user(&transid, argp, sizeof(transid))) | 
|  | return -EFAULT; | 
|  |  | 
|  | return btrfs_wait_for_commit(fs_info, transid); | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_scrub(struct file *file, void __user *arg) | 
|  | { | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file)); | 
|  | struct btrfs_ioctl_scrub_args *sa; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { | 
|  | btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | sa = memdup_user(arg, sizeof(*sa)); | 
|  | if (IS_ERR(sa)) | 
|  | return PTR_ERR(sa); | 
|  |  | 
|  | if (sa->flags & ~BTRFS_SCRUB_SUPPORTED_FLAGS) { | 
|  | ret = -EOPNOTSUPP; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | 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); | 
|  |  | 
|  | /* | 
|  | * Copy scrub args to user space even if btrfs_scrub_dev() returned an | 
|  | * error. This is important as it allows user space to know how much | 
|  | * progress scrub has done. For example, if scrub is canceled we get | 
|  | * -ECANCELED from btrfs_scrub_dev() and return that error back to user | 
|  | * space. Later user space can inspect the progress from the structure | 
|  | * btrfs_ioctl_scrub_args and resume scrub from where it left off | 
|  | * previously (btrfs-progs does this). | 
|  | * If we fail to copy the btrfs_ioctl_scrub_args structure to user space | 
|  | * then return -EFAULT to signal the structure was not copied or it may | 
|  | * be corrupt and unreliable due to a partial copy. | 
|  | */ | 
|  | if (copy_to_user(arg, sa, sizeof(*sa))) | 
|  | ret = -EFAULT; | 
|  |  | 
|  | if (!(sa->flags & BTRFS_SCRUB_READONLY)) | 
|  | mnt_drop_write_file(file); | 
|  | 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 (ret == 0 && 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 (ret == 0 && 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; | 
|  |  | 
|  | if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) { | 
|  | btrfs_err(fs_info, "device replace not supported on extent tree v2 yet"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | p = memdup_user(arg, sizeof(*p)); | 
|  | if (IS_ERR(p)) | 
|  | return PTR_ERR(p); | 
|  |  | 
|  | switch (p->cmd) { | 
|  | case BTRFS_IOCTL_DEV_REPLACE_CMD_START: | 
|  | if (sb_rdonly(fs_info->sb)) { | 
|  | ret = -EROFS; | 
|  | goto out; | 
|  | } | 
|  | if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) { | 
|  | ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; | 
|  | } else { | 
|  | ret = btrfs_dev_replace_by_ioctl(fs_info, p); | 
|  | btrfs_exclop_finish(fs_info); | 
|  | } | 
|  | break; | 
|  | case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS: | 
|  | btrfs_dev_replace_status(fs_info, p); | 
|  | ret = 0; | 
|  | break; | 
|  | case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL: | 
|  | p->result = btrfs_dev_replace_cancel(fs_info); | 
|  | ret = 0; | 
|  | break; | 
|  | default: | 
|  | ret = -EINVAL; | 
|  | break; | 
|  | } | 
|  |  | 
|  | if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p))) | 
|  | 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; | 
|  | } | 
|  |  | 
|  | btrfs_free_path(path); | 
|  | path = NULL; | 
|  | ret = copy_to_user((void __user *)(unsigned long)ipa->fspath, | 
|  | ipath->fspath, size); | 
|  | if (ret) { | 
|  | ret = -EFAULT; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | out: | 
|  | btrfs_free_path(path); | 
|  | free_ipath(ipath); | 
|  | kfree(ipa); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info, | 
|  | void __user *arg, int version) | 
|  | { | 
|  | int ret = 0; | 
|  | int size; | 
|  | struct btrfs_ioctl_logical_ino_args *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); | 
|  | } | 
|  |  | 
|  | inodes = init_data_container(size); | 
|  | if (IS_ERR(inodes)) { | 
|  | ret = PTR_ERR(inodes); | 
|  | goto out_loi; | 
|  | } | 
|  |  | 
|  | path = btrfs_alloc_path(); | 
|  | if (!path) { | 
|  | ret = -ENOMEM; | 
|  | goto out; | 
|  | } | 
|  | ret = iterate_inodes_from_logical(loi->logical, fs_info, path, | 
|  | inodes, ignore_offset); | 
|  | btrfs_free_path(path); | 
|  | 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: | 
|  | 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); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as | 
|  | * required. | 
|  | * | 
|  | * @fs_info:       the filesystem | 
|  | * @excl_acquired: ptr to boolean value which is set to false in case balance | 
|  | *                 is being resumed | 
|  | * | 
|  | * Return 0 on success in which case both fs_info::balance is acquired as well | 
|  | * as exclusive ops are blocked. In case of failure return an error code. | 
|  | */ | 
|  | static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | /* | 
|  | * Exclusive operation is locked. Three possibilities: | 
|  | *   (1) some other op is running | 
|  | *   (2) balance is running | 
|  | *   (3) balance is paused -- special case (think resume) | 
|  | */ | 
|  | while (1) { | 
|  | if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) { | 
|  | *excl_acquired = true; | 
|  | mutex_lock(&fs_info->balance_mutex); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | mutex_lock(&fs_info->balance_mutex); | 
|  | if (fs_info->balance_ctl) { | 
|  | /* This is either (2) or (3) */ | 
|  | if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { | 
|  | /* This is (2) */ | 
|  | ret = -EINPROGRESS; | 
|  | goto out_failure; | 
|  |  | 
|  | } else { | 
|  | mutex_unlock(&fs_info->balance_mutex); | 
|  | /* | 
|  | * Lock released to allow other waiters to | 
|  | * continue, we'll reexamine the status again. | 
|  | */ | 
|  | mutex_lock(&fs_info->balance_mutex); | 
|  |  | 
|  | if (fs_info->balance_ctl && | 
|  | !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) { | 
|  | /* This is (3) */ | 
|  | *excl_acquired = false; | 
|  | return 0; | 
|  | } | 
|  | } | 
|  | } else { | 
|  | /* This is (1) */ | 
|  | ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS; | 
|  | goto out_failure; | 
|  | } | 
|  |  | 
|  | mutex_unlock(&fs_info->balance_mutex); | 
|  | } | 
|  |  | 
|  | out_failure: | 
|  | mutex_unlock(&fs_info->balance_mutex); | 
|  | *excl_acquired = false; | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_balance(struct file *file, void __user *arg) | 
|  | { | 
|  | struct btrfs_root *root = BTRFS_I(file_inode(file))->root; | 
|  | struct btrfs_fs_info *fs_info = root->fs_info; | 
|  | struct btrfs_ioctl_balance_args *bargs; | 
|  | struct btrfs_balance_control *bctl; | 
|  | bool need_unlock = true; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | bargs = memdup_user(arg, sizeof(*bargs)); | 
|  | if (IS_ERR(bargs)) { | 
|  | ret = PTR_ERR(bargs); | 
|  | bargs = NULL; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = btrfs_try_lock_balance(fs_info, &need_unlock); | 
|  | if (ret) | 
|  | goto out; | 
|  |  | 
|  | lockdep_assert_held(&fs_info->balance_mutex); | 
|  |  | 
|  | if (bargs->flags & BTRFS_BALANCE_RESUME) { | 
|  | if (!fs_info->balance_ctl) { | 
|  | ret = -ENOTCONN; | 
|  | goto out_unlock; | 
|  | } | 
|  |  | 
|  | bctl = fs_info->balance_ctl; | 
|  | spin_lock(&fs_info->balance_lock); | 
|  | bctl->flags |= BTRFS_BALANCE_RESUME; | 
|  | spin_unlock(&fs_info->balance_lock); | 
|  | btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE); | 
|  |  | 
|  | goto do_balance; | 
|  | } | 
|  |  | 
|  | if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) { | 
|  | ret = -EINVAL; | 
|  | goto out_unlock; | 
|  | } | 
|  |  | 
|  | if (fs_info->balance_ctl) { | 
|  | ret = -EINPROGRESS; | 
|  | goto out_unlock; | 
|  | } | 
|  |  | 
|  | bctl = kzalloc(sizeof(*bctl), GFP_KERNEL); | 
|  | if (!bctl) { | 
|  | ret = -ENOMEM; | 
|  | goto out_unlock; | 
|  | } | 
|  |  | 
|  | memcpy(&bctl->data, &bargs->data, sizeof(bctl->data)); | 
|  | memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta)); | 
|  | memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys)); | 
|  |  | 
|  | bctl->flags = bargs->flags; | 
|  | do_balance: | 
|  | /* | 
|  | * Ownership of bctl and exclusive operation goes to btrfs_balance. | 
|  | * bctl is freed in reset_balance_state, or, if restriper was paused | 
|  | * all the way until unmount, in free_fs_info.  The flag should be | 
|  | * cleared after reset_balance_state. | 
|  | */ | 
|  | need_unlock = false; | 
|  |  | 
|  | ret = btrfs_balance(fs_info, bctl, bargs); | 
|  | bctl = NULL; | 
|  |  | 
|  | if (ret == 0 || ret == -ECANCELED) { | 
|  | if (copy_to_user(arg, bargs, sizeof(*bargs))) | 
|  | ret = -EFAULT; | 
|  | } | 
|  |  | 
|  | kfree(bctl); | 
|  | out_unlock: | 
|  | mutex_unlock(&fs_info->balance_mutex); | 
|  | if (need_unlock) | 
|  | btrfs_exclop_finish(fs_info); | 
|  | out: | 
|  | mnt_drop_write_file(file); | 
|  | kfree(bargs); | 
|  | 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 = inode_to_fs_info(inode); | 
|  | 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; | 
|  | } | 
|  |  | 
|  | switch (sa->cmd) { | 
|  | case BTRFS_QUOTA_CTL_ENABLE: | 
|  | case BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA: | 
|  | down_write(&fs_info->subvol_sem); | 
|  | ret = btrfs_quota_enable(fs_info, sa); | 
|  | up_write(&fs_info->subvol_sem); | 
|  | break; | 
|  | case BTRFS_QUOTA_CTL_DISABLE: | 
|  | /* | 
|  | * Lock the cleaner mutex to prevent races with concurrent | 
|  | * relocation, because relocation may be building backrefs for | 
|  | * blocks of the quota root while we are deleting the root. This | 
|  | * is like dropping fs roots of deleted snapshots/subvolumes, we | 
|  | * need the same protection. | 
|  | * | 
|  | * This also prevents races between concurrent tasks trying to | 
|  | * disable quotas, because we will unlock and relock | 
|  | * qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes. | 
|  | * | 
|  | * We take this here because we have the dependency of | 
|  | * | 
|  | * inode_lock -> subvol_sem | 
|  | * | 
|  | * because of rename.  With relocation we can prealloc extents, | 
|  | * so that makes the dependency chain | 
|  | * | 
|  | * cleaner_mutex -> inode_lock -> subvol_sem | 
|  | * | 
|  | * so we must take the cleaner_mutex here before we take the | 
|  | * subvol_sem.  The deadlock can't actually happen, but this | 
|  | * quiets lockdep. | 
|  | */ | 
|  | mutex_lock(&fs_info->cleaner_mutex); | 
|  | down_write(&fs_info->subvol_sem); | 
|  | ret = btrfs_quota_disable(fs_info); | 
|  | up_write(&fs_info->subvol_sem); | 
|  | mutex_unlock(&fs_info->cleaner_mutex); | 
|  | break; | 
|  | default: | 
|  | ret = -EINVAL; | 
|  | break; | 
|  | } | 
|  |  | 
|  | kfree(sa); | 
|  | drop_write: | 
|  | mnt_drop_write_file(file); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Quick check for ioctl handlers if quotas are enabled. Proper locking must be | 
|  | * done before any operations. | 
|  | */ | 
|  | static bool qgroup_enabled(struct btrfs_fs_info *fs_info) | 
|  | { | 
|  | bool ret = true; | 
|  |  | 
|  | mutex_lock(&fs_info->qgroup_ioctl_lock); | 
|  | if (!fs_info->quota_root) | 
|  | ret = false; | 
|  | mutex_unlock(&fs_info->qgroup_ioctl_lock); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_ioctl_qgroup_assign_args *sa; | 
|  | struct btrfs_qgroup_list *prealloc = NULL; | 
|  | struct btrfs_trans_handle *trans; | 
|  | int ret; | 
|  | int err; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (!qgroup_enabled(root->fs_info)) | 
|  | return -ENOTCONN; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | sa = memdup_user(arg, sizeof(*sa)); | 
|  | if (IS_ERR(sa)) { | 
|  | ret = PTR_ERR(sa); | 
|  | goto drop_write; | 
|  | } | 
|  |  | 
|  | if (sa->assign) { | 
|  | prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL); | 
|  | if (!prealloc) { | 
|  | ret = -ENOMEM; | 
|  | goto drop_write; | 
|  | } | 
|  | } | 
|  |  | 
|  | trans = btrfs_join_transaction(root); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Prealloc ownership is moved to the relation handler, there it's used | 
|  | * or freed on error. | 
|  | */ | 
|  | if (sa->assign) { | 
|  | ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst, prealloc); | 
|  | prealloc = NULL; | 
|  | } else { | 
|  | ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst); | 
|  | } | 
|  |  | 
|  | /* update qgroup status and info */ | 
|  | mutex_lock(&fs_info->qgroup_ioctl_lock); | 
|  | err = btrfs_run_qgroups(trans); | 
|  | mutex_unlock(&fs_info->qgroup_ioctl_lock); | 
|  | if (err < 0) | 
|  | btrfs_warn(fs_info, | 
|  | "qgroup status update failed after %s relation, marked as inconsistent", | 
|  | sa->assign ? "adding" : "deleting"); | 
|  | err = btrfs_end_transaction(trans); | 
|  | if (err && !ret) | 
|  | ret = err; | 
|  |  | 
|  | out: | 
|  | kfree(prealloc); | 
|  | 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; | 
|  |  | 
|  | if (!qgroup_enabled(root->fs_info)) | 
|  | return -ENOTCONN; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | sa = memdup_user(arg, sizeof(*sa)); | 
|  | if (IS_ERR(sa)) { | 
|  | ret = PTR_ERR(sa); | 
|  | goto drop_write; | 
|  | } | 
|  |  | 
|  | if (!sa->qgroupid) { | 
|  | ret = -EINVAL; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if (sa->create && is_fstree(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; | 
|  |  | 
|  | if (!qgroup_enabled(root->fs_info)) | 
|  | return -ENOTCONN; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | sa = memdup_user(arg, sizeof(*sa)); | 
|  | if (IS_ERR(sa)) { | 
|  | ret = PTR_ERR(sa); | 
|  | goto drop_write; | 
|  | } | 
|  |  | 
|  | 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 = btrfs_root_id(root); | 
|  | } | 
|  |  | 
|  | 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 = inode_to_fs_info(inode); | 
|  | struct btrfs_ioctl_quota_rescan_args *qsa; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (!qgroup_enabled(fs_info)) | 
|  | return -ENOTCONN; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | qsa = memdup_user(arg, sizeof(*qsa)); | 
|  | if (IS_ERR(qsa)) { | 
|  | ret = PTR_ERR(qsa); | 
|  | goto drop_write; | 
|  | } | 
|  |  | 
|  | if (qsa->flags) { | 
|  | ret = -EINVAL; | 
|  | goto 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 btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | struct btrfs_ioctl_quota_rescan_args qsa = {0}; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) { | 
|  | qsa.flags = 1; | 
|  | qsa.progress = fs_info->qgroup_rescan_progress.objectid; | 
|  | } | 
|  |  | 
|  | if (copy_to_user(arg, &qsa, sizeof(qsa))) | 
|  | return -EFAULT; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | return btrfs_qgroup_wait_for_completion(fs_info, true); | 
|  | } | 
|  |  | 
|  | static long _btrfs_ioctl_set_received_subvol(struct file *file, | 
|  | struct mnt_idmap *idmap, | 
|  | struct btrfs_ioctl_received_subvol_args *sa) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_root_item *root_item = &root->root_item; | 
|  | struct btrfs_trans_handle *trans; | 
|  | struct timespec64 ct = current_time(inode); | 
|  | int ret = 0; | 
|  | int received_uuid_changed; | 
|  |  | 
|  | if (!inode_owner_or_capable(idmap, inode)) | 
|  | return -EPERM; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret < 0) | 
|  | return ret; | 
|  |  | 
|  | down_write(&fs_info->subvol_sem); | 
|  |  | 
|  | if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) { | 
|  | ret = -EINVAL; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if (btrfs_root_readonly(root)) { | 
|  | ret = -EROFS; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * 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, | 
|  | btrfs_root_id(root)); | 
|  | 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, | 
|  | btrfs_root_id(root)); | 
|  | 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, file_mnt_idmap(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, file_mnt_idmap(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 btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | size_t len; | 
|  | int ret; | 
|  | char label[BTRFS_LABEL_SIZE]; | 
|  |  | 
|  | spin_lock(&fs_info->super_lock); | 
|  | memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE); | 
|  | spin_unlock(&fs_info->super_lock); | 
|  |  | 
|  | len = strnlen(label, BTRFS_LABEL_SIZE); | 
|  |  | 
|  | if (len == BTRFS_LABEL_SIZE) { | 
|  | btrfs_warn(fs_info, | 
|  | "label is too long, return the first %zu bytes", | 
|  | --len); | 
|  | } | 
|  |  | 
|  | ret = copy_to_user(arg, label, len); | 
|  |  | 
|  | return ret ? -EFAULT : 0; | 
|  | } | 
|  |  | 
|  | static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_super_block *super_block = fs_info->super_copy; | 
|  | struct btrfs_trans_handle *trans; | 
|  | char label[BTRFS_LABEL_SIZE]; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (copy_from_user(label, arg, sizeof(label))) | 
|  | return -EFAULT; | 
|  |  | 
|  | if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { | 
|  | btrfs_err(fs_info, | 
|  | "unable to set label with more than %d bytes", | 
|  | BTRFS_LABEL_SIZE - 1); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 0); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_unlock; | 
|  | } | 
|  |  | 
|  | spin_lock(&fs_info->super_lock); | 
|  | 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 btrfs_fs_info *fs_info, | 
|  | void __user *arg) | 
|  | { | 
|  | struct btrfs_super_block *super_block = fs_info->super_copy; | 
|  | struct btrfs_ioctl_feature_flags features; | 
|  |  | 
|  | features.compat_flags = btrfs_super_compat_flags(super_block); | 
|  | features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block); | 
|  | features.incompat_flags = btrfs_super_incompat_flags(super_block); | 
|  |  | 
|  | if (copy_to_user(arg, &features, sizeof(features))) | 
|  | return -EFAULT; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int check_feature_bits(struct btrfs_fs_info *fs_info, | 
|  | enum btrfs_feature_set set, | 
|  | u64 change_mask, u64 flags, u64 supported_flags, | 
|  | u64 safe_set, u64 safe_clear) | 
|  | { | 
|  | const char *type = btrfs_feature_set_name(set); | 
|  | 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 = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | struct btrfs_super_block *super_block = fs_info->super_copy; | 
|  | struct btrfs_ioctl_feature_flags flags[2]; | 
|  | struct btrfs_trans_handle *trans; | 
|  | u64 newflags; | 
|  | int ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) | 
|  | return -EPERM; | 
|  |  | 
|  | if (copy_from_user(flags, arg, sizeof(flags))) | 
|  | return -EFAULT; | 
|  |  | 
|  | /* Nothing to do */ | 
|  | if (!flags[0].compat_flags && !flags[0].compat_ro_flags && | 
|  | !flags[0].incompat_flags) | 
|  | return 0; | 
|  |  | 
|  | ret = check_feature(fs_info, flags[0].compat_flags, | 
|  | flags[1].compat_flags, COMPAT); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = check_feature(fs_info, flags[0].compat_ro_flags, | 
|  | flags[1].compat_ro_flags, COMPAT_RO); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = check_feature(fs_info, flags[0].incompat_flags, | 
|  | flags[1].incompat_flags, INCOMPAT); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = mnt_want_write_file(file); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | trans = btrfs_start_transaction(root, 0); | 
|  | if (IS_ERR(trans)) { | 
|  | ret = PTR_ERR(trans); | 
|  | goto out_drop_write; | 
|  | } | 
|  |  | 
|  | spin_lock(&fs_info->super_lock); | 
|  | newflags = btrfs_super_compat_flags(super_block); | 
|  | newflags |= flags[0].compat_flags & flags[1].compat_flags; | 
|  | newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags); | 
|  | btrfs_set_super_compat_flags(super_block, newflags); | 
|  |  | 
|  | newflags = btrfs_super_compat_ro_flags(super_block); | 
|  | newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags; | 
|  | newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags); | 
|  | btrfs_set_super_compat_ro_flags(super_block, newflags); | 
|  |  | 
|  | newflags = btrfs_super_incompat_flags(super_block); | 
|  | newflags |= flags[0].incompat_flags & flags[1].incompat_flags; | 
|  | newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags); | 
|  | btrfs_set_super_incompat_flags(super_block, newflags); | 
|  | spin_unlock(&fs_info->super_lock); | 
|  |  | 
|  | ret = btrfs_commit_transaction(trans); | 
|  | out_drop_write: | 
|  | mnt_drop_write_file(file); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int _btrfs_ioctl_send(struct btrfs_inode *inode, 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 = { 0 }; | 
|  |  | 
|  | 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; | 
|  | arg->version = args32.version; | 
|  | memcpy(arg->reserved, args32.reserved, | 
|  | sizeof(args32.reserved)); | 
|  | #else | 
|  | return -ENOTTY; | 
|  | #endif | 
|  | } else { | 
|  | arg = memdup_user(argp, sizeof(*arg)); | 
|  | if (IS_ERR(arg)) | 
|  | return PTR_ERR(arg); | 
|  | } | 
|  | ret = btrfs_ioctl_send(inode, arg); | 
|  | kfree(arg); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp, | 
|  | bool compat) | 
|  | { | 
|  | struct btrfs_ioctl_encoded_io_args args = { 0 }; | 
|  | size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args, | 
|  | flags); | 
|  | size_t copy_end; | 
|  | struct btrfs_inode *inode = BTRFS_I(file_inode(file)); | 
|  | struct btrfs_fs_info *fs_info = inode->root->fs_info; | 
|  | struct extent_io_tree *io_tree = &inode->io_tree; | 
|  | struct iovec iovstack[UIO_FASTIOV]; | 
|  | struct iovec *iov = iovstack; | 
|  | struct iov_iter iter; | 
|  | loff_t pos; | 
|  | struct kiocb kiocb; | 
|  | ssize_t ret; | 
|  | u64 disk_bytenr, disk_io_size; | 
|  | struct extent_state *cached_state = NULL; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) { | 
|  | ret = -EPERM; | 
|  | goto out_acct; | 
|  | } | 
|  |  | 
|  | if (compat) { | 
|  | #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) | 
|  | struct btrfs_ioctl_encoded_io_args_32 args32; | 
|  |  | 
|  | copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32, | 
|  | flags); | 
|  | if (copy_from_user(&args32, argp, copy_end)) { | 
|  | ret = -EFAULT; | 
|  | goto out_acct; | 
|  | } | 
|  | args.iov = compat_ptr(args32.iov); | 
|  | args.iovcnt = args32.iovcnt; | 
|  | args.offset = args32.offset; | 
|  | args.flags = args32.flags; | 
|  | #else | 
|  | return -ENOTTY; | 
|  | #endif | 
|  | } else { | 
|  | copy_end = copy_end_kernel; | 
|  | if (copy_from_user(&args, argp, copy_end)) { | 
|  | ret = -EFAULT; | 
|  | goto out_acct; | 
|  | } | 
|  | } | 
|  | if (args.flags != 0) { | 
|  | ret = -EINVAL; | 
|  | goto out_acct; | 
|  | } | 
|  |  | 
|  | ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack), | 
|  | &iov, &iter); | 
|  | if (ret < 0) | 
|  | goto out_acct; | 
|  |  | 
|  | if (iov_iter_count(&iter) == 0) { | 
|  | ret = 0; | 
|  | goto out_iov; | 
|  | } | 
|  | pos = args.offset; | 
|  | ret = rw_verify_area(READ, file, &pos, args.len); | 
|  | if (ret < 0) | 
|  | goto out_iov; | 
|  |  | 
|  | init_sync_kiocb(&kiocb, file); | 
|  | kiocb.ki_pos = pos; | 
|  |  | 
|  | ret = btrfs_encoded_read(&kiocb, &iter, &args, &cached_state, | 
|  | &disk_bytenr, &disk_io_size); | 
|  |  | 
|  | if (ret == -EIOCBQUEUED) { | 
|  | bool unlocked = false; | 
|  | u64 start, lockend, count; | 
|  |  | 
|  | start = ALIGN_DOWN(kiocb.ki_pos, fs_info->sectorsize); | 
|  | lockend = start + BTRFS_MAX_UNCOMPRESSED - 1; | 
|  |  | 
|  | if (args.compression) | 
|  | count = disk_io_size; | 
|  | else | 
|  | count = args.len; | 
|  |  | 
|  | ret = btrfs_encoded_read_regular(&kiocb, &iter, start, lockend, | 
|  | &cached_state, disk_bytenr, | 
|  | disk_io_size, count, | 
|  | args.compression, &unlocked); | 
|  |  | 
|  | if (!unlocked) { | 
|  | unlock_extent(io_tree, start, lockend, &cached_state); | 
|  | btrfs_inode_unlock(inode, BTRFS_ILOCK_SHARED); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (ret >= 0) { | 
|  | fsnotify_access(file); | 
|  | if (copy_to_user(argp + copy_end, | 
|  | (char *)&args + copy_end_kernel, | 
|  | sizeof(args) - copy_end_kernel)) | 
|  | ret = -EFAULT; | 
|  | } | 
|  |  | 
|  | out_iov: | 
|  | kfree(iov); | 
|  | out_acct: | 
|  | if (ret > 0) | 
|  | add_rchar(current, ret); | 
|  | inc_syscr(current); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat) | 
|  | { | 
|  | struct btrfs_ioctl_encoded_io_args args; | 
|  | struct iovec iovstack[UIO_FASTIOV]; | 
|  | struct iovec *iov = iovstack; | 
|  | struct iov_iter iter; | 
|  | loff_t pos; | 
|  | struct kiocb kiocb; | 
|  | ssize_t ret; | 
|  |  | 
|  | if (!capable(CAP_SYS_ADMIN)) { | 
|  | ret = -EPERM; | 
|  | goto out_acct; | 
|  | } | 
|  |  | 
|  | if (!(file->f_mode & FMODE_WRITE)) { | 
|  | ret = -EBADF; | 
|  | goto out_acct; | 
|  | } | 
|  |  | 
|  | if (compat) { | 
|  | #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) | 
|  | struct btrfs_ioctl_encoded_io_args_32 args32; | 
|  |  | 
|  | if (copy_from_user(&args32, argp, sizeof(args32))) { | 
|  | ret = -EFAULT; | 
|  | goto out_acct; | 
|  | } | 
|  | args.iov = compat_ptr(args32.iov); | 
|  | args.iovcnt = args32.iovcnt; | 
|  | args.offset = args32.offset; | 
|  | args.flags = args32.flags; | 
|  | args.len = args32.len; | 
|  | args.unencoded_len = args32.unencoded_len; | 
|  | args.unencoded_offset = args32.unencoded_offset; | 
|  | args.compression = args32.compression; | 
|  | args.encryption = args32.encryption; | 
|  | memcpy(args.reserved, args32.reserved, sizeof(args.reserved)); | 
|  | #else | 
|  | return -ENOTTY; | 
|  | #endif | 
|  | } else { | 
|  | if (copy_from_user(&args, argp, sizeof(args))) { | 
|  | ret = -EFAULT; | 
|  | goto out_acct; | 
|  | } | 
|  | } | 
|  |  | 
|  | ret = -EINVAL; | 
|  | if (args.flags != 0) | 
|  | goto out_acct; | 
|  | if (memchr_inv(args.reserved, 0, sizeof(args.reserved))) | 
|  | goto out_acct; | 
|  | if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE && | 
|  | args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE) | 
|  | goto out_acct; | 
|  | if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES || | 
|  | args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES) | 
|  | goto out_acct; | 
|  | if (args.unencoded_offset > args.unencoded_len) | 
|  | goto out_acct; | 
|  | if (args.len > args.unencoded_len - args.unencoded_offset) | 
|  | goto out_acct; | 
|  |  | 
|  | ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack), | 
|  | &iov, &iter); | 
|  | if (ret < 0) | 
|  | goto out_acct; | 
|  |  | 
|  | if (iov_iter_count(&iter) == 0) { | 
|  | ret = 0; | 
|  | goto out_iov; | 
|  | } | 
|  | pos = args.offset; | 
|  | ret = rw_verify_area(WRITE, file, &pos, args.len); | 
|  | if (ret < 0) | 
|  | goto out_iov; | 
|  |  | 
|  | init_sync_kiocb(&kiocb, file); | 
|  | ret = kiocb_set_rw_flags(&kiocb, 0, WRITE); | 
|  | if (ret) | 
|  | goto out_iov; | 
|  | kiocb.ki_pos = pos; | 
|  |  | 
|  | file_start_write(file); | 
|  |  | 
|  | ret = btrfs_do_write_iter(&kiocb, &iter, &args); | 
|  | if (ret > 0) | 
|  | fsnotify_modify(file); | 
|  |  | 
|  | file_end_write(file); | 
|  | out_iov: | 
|  | kfree(iov); | 
|  | out_acct: | 
|  | if (ret > 0) | 
|  | add_wchar(current, ret); | 
|  | inc_syscw(current); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | long btrfs_ioctl(struct file *file, unsigned int | 
|  | cmd, unsigned long arg) | 
|  | { | 
|  | struct inode *inode = file_inode(file); | 
|  | struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); | 
|  | struct btrfs_root *root = BTRFS_I(inode)->root; | 
|  | void __user *argp = (void __user *)arg; | 
|  |  | 
|  | switch (cmd) { | 
|  | case FS_IOC_GETVERSION: | 
|  | return btrfs_ioctl_getversion(inode, argp); | 
|  | case FS_IOC_GETFSLABEL: | 
|  | return btrfs_ioctl_get_fslabel(fs_info, argp); | 
|  | case FS_IOC_SETFSLABEL: | 
|  | return btrfs_ioctl_set_fslabel(file, argp); | 
|  | case FITRIM: | 
|  | return btrfs_ioctl_fitrim(fs_info, argp); | 
|  | case BTRFS_IOC_SNAP_CREATE: | 
|  | return btrfs_ioctl_snap_create(file, argp, 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, false); | 
|  | case BTRFS_IOC_SNAP_DESTROY_V2: | 
|  | return btrfs_ioctl_snap_destroy(file, argp, true); | 
|  | case BTRFS_IOC_SUBVOL_GETFLAGS: | 
|  | return btrfs_ioctl_subvol_getflags(inode, argp); | 
|  | case BTRFS_IOC_SUBVOL_SETFLAGS: | 
|  | return btrfs_ioctl_subvol_setflags(file, argp); | 
|  | case BTRFS_IOC_DEFAULT_SUBVOL: | 
|  | return btrfs_ioctl_default_subvol(file, argp); | 
|  | case BTRFS_IOC_DEFRAG: | 
|  | return btrfs_ioctl_defrag(file, NULL); | 
|  | case BTRFS_IOC_DEFRAG_RANGE: | 
|  | return btrfs_ioctl_defrag(file, argp); | 
|  | case BTRFS_IOC_RESIZE: | 
|  | return btrfs_ioctl_resize(file, argp); | 
|  | case BTRFS_IOC_ADD_DEV: | 
|  | return btrfs_ioctl_add_dev(fs_info, argp); | 
|  | case BTRFS_IOC_RM_DEV: | 
|  | return btrfs_ioctl_rm_dev(file, argp); | 
|  | case BTRFS_IOC_RM_DEV_V2: | 
|  | return btrfs_ioctl_rm_dev_v2(file, argp); | 
|  | case BTRFS_IOC_FS_INFO: | 
|  | return btrfs_ioctl_fs_info(fs_info, argp); | 
|  | case BTRFS_IOC_DEV_INFO: | 
|  | return btrfs_ioctl_dev_info(fs_info, argp); | 
|  | case BTRFS_IOC_TREE_SEARCH: | 
|  | return btrfs_ioctl_tree_search(inode, argp); | 
|  | case BTRFS_IOC_TREE_SEARCH_V2: | 
|  | return btrfs_ioctl_tree_search_v2(inode, argp); | 
|  | case BTRFS_IOC_INO_LOOKUP: | 
|  | return btrfs_ioctl_ino_lookup(root, argp); | 
|  | case BTRFS_IOC_INO_PATHS: | 
|  | return btrfs_ioctl_ino_to_path(root, argp); | 
|  | case BTRFS_IOC_LOGICAL_INO: | 
|  | return btrfs_ioctl_logical_to_ino(fs_info, argp, 1); | 
|  | case BTRFS_IOC_LOGICAL_INO_V2: | 
|  | return btrfs_ioctl_logical_to_ino(fs_info, argp, 2); | 
|  | case BTRFS_IOC_SPACE_INFO: | 
|  | return btrfs_ioctl_space_info(fs_info, argp); | 
|  | case BTRFS_IOC_SYNC: { | 
|  | int ret; | 
|  |  | 
|  | ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false); | 
|  | if (ret) | 
|  | return ret; | 
|  | ret = btrfs_sync_fs(inode->i_sb, 1); | 
|  | /* | 
|  | * There may be work for the cleaner kthread to do (subvolume | 
|  | * deletion, delayed iputs, defrag inodes, etc), so wake it up. | 
|  | */ | 
|  | wake_up_process(fs_info->cleaner_kthread); | 
|  | return ret; | 
|  | } | 
|  | case BTRFS_IOC_START_SYNC: | 
|  | return btrfs_ioctl_start_sync(root, argp); | 
|  | case BTRFS_IOC_WAIT_SYNC: | 
|  | return btrfs_ioctl_wait_sync(fs_info, argp); | 
|  | case BTRFS_IOC_SCRUB: | 
|  | return btrfs_ioctl_scrub(file, argp); | 
|  | case BTRFS_IOC_SCRUB_CANCEL: | 
|  | return btrfs_ioctl_scrub_cancel(fs_info); | 
|  | case BTRFS_IOC_SCRUB_PROGRESS: | 
|  | return btrfs_ioctl_scrub_progress(fs_info, argp); | 
|  | case BTRFS_IOC_BALANCE_V2: | 
|  | return btrfs_ioctl_balance(file, argp); | 
|  | case BTRFS_IOC_BALANCE_CTL: | 
|  | return btrfs_ioctl_balance_ctl(fs_info, arg); | 
|  | case BTRFS_IOC_BALANCE_PROGRESS: | 
|  | return btrfs_ioctl_balance_progress(fs_info, argp); | 
|  | case BTRFS_IOC_SET_RECEIVED_SUBVOL: | 
|  | return btrfs_ioctl_set_received_subvol(file, argp); | 
|  | #ifdef CONFIG_64BIT | 
|  | case BTRFS_IOC_SET_RECEIVED_SUBVOL_32: | 
|  | return btrfs_ioctl_set_received_subvol_32(file, argp); | 
|  | #endif | 
|  | case BTRFS_IOC_SEND: | 
|  | return _btrfs_ioctl_send(BTRFS_I(inode), argp, false); | 
|  | #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) | 
|  | case BTRFS_IOC_SEND_32: | 
|  | return _btrfs_ioctl_send(BTRFS_I(inode), argp, true); | 
|  | #endif | 
|  | case BTRFS_IOC_GET_DEV_STATS: | 
|  | return btrfs_ioctl_get_dev_stats(fs_info, argp); | 
|  | case BTRFS_IOC_QUOTA_CTL: | 
|  | return btrfs_ioctl_quota_ctl(file, argp); | 
|  | case BTRFS_IOC_QGROUP_ASSIGN: | 
|  | return btrfs_ioctl_qgroup_assign(file, argp); | 
|  | case BTRFS_IOC_QGROUP_CREATE: | 
|  | return btrfs_ioctl_qgroup_create(file, argp); | 
|  | case BTRFS_IOC_QGROUP_LIMIT: | 
|  | return btrfs_ioctl_qgroup_limit(file, argp); | 
|  | case BTRFS_IOC_QUOTA_RESCAN: | 
|  | return btrfs_ioctl_quota_rescan(file, argp); | 
|  | case BTRFS_IOC_QUOTA_RESCAN_STATUS: | 
|  | return btrfs_ioctl_quota_rescan_status(fs_info, argp); | 
|  | case BTRFS_IOC_QUOTA_RESCAN_WAIT: | 
|  | return btrfs_ioctl_quota_rescan_wait(fs_info, argp); | 
|  | case BTRFS_IOC_DEV_REPLACE: | 
|  | return btrfs_ioctl_dev_replace(fs_info, argp); | 
|  | case BTRFS_IOC_GET_SUPPORTED_FEATURES: | 
|  | return btrfs_ioctl_get_supported_features(argp); | 
|  | case BTRFS_IOC_GET_FEATURES: | 
|  | return btrfs_ioctl_get_features(fs_info, argp); | 
|  | case BTRFS_IOC_SET_FEATURES: | 
|  | return btrfs_ioctl_set_features(file, argp); | 
|  | case BTRFS_IOC_GET_SUBVOL_INFO: | 
|  | return btrfs_ioctl_get_subvol_info(inode, argp); | 
|  | case BTRFS_IOC_GET_SUBVOL_ROOTREF: | 
|  | return btrfs_ioctl_get_subvol_rootref(root, argp); | 
|  | case BTRFS_IOC_INO_LOOKUP_USER: | 
|  | return btrfs_ioctl_ino_lookup_user(file, argp); | 
|  | case FS_IOC_ENABLE_VERITY: | 
|  | return fsverity_ioctl_enable(file, (const void __user *)argp); | 
|  | case FS_IOC_MEASURE_VERITY: | 
|  | return fsverity_ioctl_measure(file, argp); | 
|  | case BTRFS_IOC_ENCODED_READ: | 
|  | return btrfs_ioctl_encoded_read(file, argp, false); | 
|  | case BTRFS_IOC_ENCODED_WRITE: | 
|  | return btrfs_ioctl_encoded_write(file, argp, false); | 
|  | #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT) | 
|  | case BTRFS_IOC_ENCODED_READ_32: | 
|  | return btrfs_ioctl_encoded_read(file, argp, true); | 
|  | case BTRFS_IOC_ENCODED_WRITE_32: | 
|  | return btrfs_ioctl_encoded_write(file, argp, true); | 
|  | #endif | 
|  | } | 
|  |  | 
|  | return -ENOTTY; | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_COMPAT | 
|  | long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | 
|  | { | 
|  | /* | 
|  | * These all access 32-bit values anyway so no further | 
|  | * handling is necessary. | 
|  | */ | 
|  | switch (cmd) { | 
|  | case FS_IOC32_GETVERSION: | 
|  | cmd = FS_IOC_GETVERSION; | 
|  | break; | 
|  | } | 
|  |  | 
|  | return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); | 
|  | } | 
|  | #endif |