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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2007 Oracle. All rights reserved.4 */5 6#include <linux/kernel.h>7#include <linux/bio.h>8#include <linux/file.h>9#include <linux/fs.h>10#include <linux/fsnotify.h>11#include <linux/pagemap.h>12#include <linux/highmem.h>13#include <linux/time.h>14#include <linux/string.h>15#include <linux/backing-dev.h>16#include <linux/mount.h>17#include <linux/namei.h>18#include <linux/writeback.h>19#include <linux/compat.h>20#include <linux/security.h>21#include <linux/xattr.h>22#include <linux/mm.h>23#include <linux/slab.h>24#include <linux/blkdev.h>25#include <linux/uuid.h>26#include <linux/btrfs.h>27#include <linux/uaccess.h>28#include <linux/iversion.h>29#include <linux/fileattr.h>30#include <linux/fsverity.h>31#include <linux/sched/xacct.h>32#include "ctree.h"33#include "disk-io.h"34#include "export.h"35#include "transaction.h"36#include "btrfs_inode.h"37#include "volumes.h"38#include "locking.h"39#include "backref.h"40#include "send.h"41#include "dev-replace.h"42#include "props.h"43#include "sysfs.h"44#include "qgroup.h"45#include "tree-log.h"46#include "compression.h"47#include "space-info.h"48#include "block-group.h"49#include "fs.h"50#include "accessors.h"51#include "extent-tree.h"52#include "root-tree.h"53#include "defrag.h"54#include "dir-item.h"55#include "uuid-tree.h"56#include "ioctl.h"57#include "file.h"58#include "scrub.h"59#include "super.h"60 61#ifdef CONFIG_64BIT62/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI63 * structures are incorrect, as the timespec structure from userspace64 * is 4 bytes too small. We define these alternatives here to teach65 * the kernel about the 32-bit struct packing.66 */67struct btrfs_ioctl_timespec_32 {68 __u64 sec;69 __u32 nsec;70} __attribute__ ((__packed__));71 72struct btrfs_ioctl_received_subvol_args_32 {73 char uuid[BTRFS_UUID_SIZE]; /* in */74 __u64 stransid; /* in */75 __u64 rtransid; /* out */76 struct btrfs_ioctl_timespec_32 stime; /* in */77 struct btrfs_ioctl_timespec_32 rtime; /* out */78 __u64 flags; /* in */79 __u64 reserved[16]; /* in */80} __attribute__ ((__packed__));81 82#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \83 struct btrfs_ioctl_received_subvol_args_32)84#endif85 86#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)87struct btrfs_ioctl_send_args_32 {88 __s64 send_fd; /* in */89 __u64 clone_sources_count; /* in */90 compat_uptr_t clone_sources; /* in */91 __u64 parent_root; /* in */92 __u64 flags; /* in */93 __u32 version; /* in */94 __u8 reserved[28]; /* in */95} __attribute__ ((__packed__));96 97#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \98 struct btrfs_ioctl_send_args_32)99 100struct btrfs_ioctl_encoded_io_args_32 {101 compat_uptr_t iov;102 compat_ulong_t iovcnt;103 __s64 offset;104 __u64 flags;105 __u64 len;106 __u64 unencoded_len;107 __u64 unencoded_offset;108 __u32 compression;109 __u32 encryption;110 __u8 reserved[64];111};112 113#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \114 struct btrfs_ioctl_encoded_io_args_32)115#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \116 struct btrfs_ioctl_encoded_io_args_32)117#endif118 119/* Mask out flags that are inappropriate for the given type of inode. */120static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,121 unsigned int flags)122{123 if (S_ISDIR(inode->i_mode))124 return flags;125 else if (S_ISREG(inode->i_mode))126 return flags & ~FS_DIRSYNC_FL;127 else128 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);129}130 131/*132 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS133 * ioctl.134 */135static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)136{137 unsigned int iflags = 0;138 u32 flags = binode->flags;139 u32 ro_flags = binode->ro_flags;140 141 if (flags & BTRFS_INODE_SYNC)142 iflags |= FS_SYNC_FL;143 if (flags & BTRFS_INODE_IMMUTABLE)144 iflags |= FS_IMMUTABLE_FL;145 if (flags & BTRFS_INODE_APPEND)146 iflags |= FS_APPEND_FL;147 if (flags & BTRFS_INODE_NODUMP)148 iflags |= FS_NODUMP_FL;149 if (flags & BTRFS_INODE_NOATIME)150 iflags |= FS_NOATIME_FL;151 if (flags & BTRFS_INODE_DIRSYNC)152 iflags |= FS_DIRSYNC_FL;153 if (flags & BTRFS_INODE_NODATACOW)154 iflags |= FS_NOCOW_FL;155 if (ro_flags & BTRFS_INODE_RO_VERITY)156 iflags |= FS_VERITY_FL;157 158 if (flags & BTRFS_INODE_NOCOMPRESS)159 iflags |= FS_NOCOMP_FL;160 else if (flags & BTRFS_INODE_COMPRESS)161 iflags |= FS_COMPR_FL;162 163 return iflags;164}165 166/*167 * Update inode->i_flags based on the btrfs internal flags.168 */169void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)170{171 struct btrfs_inode *binode = BTRFS_I(inode);172 unsigned int new_fl = 0;173 174 if (binode->flags & BTRFS_INODE_SYNC)175 new_fl |= S_SYNC;176 if (binode->flags & BTRFS_INODE_IMMUTABLE)177 new_fl |= S_IMMUTABLE;178 if (binode->flags & BTRFS_INODE_APPEND)179 new_fl |= S_APPEND;180 if (binode->flags & BTRFS_INODE_NOATIME)181 new_fl |= S_NOATIME;182 if (binode->flags & BTRFS_INODE_DIRSYNC)183 new_fl |= S_DIRSYNC;184 if (binode->ro_flags & BTRFS_INODE_RO_VERITY)185 new_fl |= S_VERITY;186 187 set_mask_bits(&inode->i_flags,188 S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |189 S_VERITY, new_fl);190}191 192/*193 * Check if @flags are a supported and valid set of FS_*_FL flags and that194 * the old and new flags are not conflicting195 */196static int check_fsflags(unsigned int old_flags, unsigned int flags)197{198 if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \199 FS_NOATIME_FL | FS_NODUMP_FL | \200 FS_SYNC_FL | FS_DIRSYNC_FL | \201 FS_NOCOMP_FL | FS_COMPR_FL |202 FS_NOCOW_FL))203 return -EOPNOTSUPP;204 205 /* COMPR and NOCOMP on new/old are valid */206 if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))207 return -EINVAL;208 209 if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))210 return -EINVAL;211 212 /* NOCOW and compression options are mutually exclusive */213 if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))214 return -EINVAL;215 if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))216 return -EINVAL;217 218 return 0;219}220 221static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,222 unsigned int flags)223{224 if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))225 return -EPERM;226 227 return 0;228}229 230int btrfs_check_ioctl_vol_args_path(const struct btrfs_ioctl_vol_args *vol_args)231{232 if (memchr(vol_args->name, 0, sizeof(vol_args->name)) == NULL)233 return -ENAMETOOLONG;234 return 0;235}236 237static int btrfs_check_ioctl_vol_args2_subvol_name(const struct btrfs_ioctl_vol_args_v2 *vol_args2)238{239 if (memchr(vol_args2->name, 0, sizeof(vol_args2->name)) == NULL)240 return -ENAMETOOLONG;241 return 0;242}243 244/*245 * Set flags/xflags from the internal inode flags. The remaining items of246 * fsxattr are zeroed.247 */248int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)249{250 struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));251 252 fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));253 return 0;254}255 256int btrfs_fileattr_set(struct mnt_idmap *idmap,257 struct dentry *dentry, struct fileattr *fa)258{259 struct inode *inode = d_inode(dentry);260 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);261 struct btrfs_inode *binode = BTRFS_I(inode);262 struct btrfs_root *root = binode->root;263 struct btrfs_trans_handle *trans;264 unsigned int fsflags, old_fsflags;265 int ret;266 const char *comp = NULL;267 u32 binode_flags;268 269 if (btrfs_root_readonly(root))270 return -EROFS;271 272 if (fileattr_has_fsx(fa))273 return -EOPNOTSUPP;274 275 fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);276 old_fsflags = btrfs_inode_flags_to_fsflags(binode);277 ret = check_fsflags(old_fsflags, fsflags);278 if (ret)279 return ret;280 281 ret = check_fsflags_compatible(fs_info, fsflags);282 if (ret)283 return ret;284 285 binode_flags = binode->flags;286 if (fsflags & FS_SYNC_FL)287 binode_flags |= BTRFS_INODE_SYNC;288 else289 binode_flags &= ~BTRFS_INODE_SYNC;290 if (fsflags & FS_IMMUTABLE_FL)291 binode_flags |= BTRFS_INODE_IMMUTABLE;292 else293 binode_flags &= ~BTRFS_INODE_IMMUTABLE;294 if (fsflags & FS_APPEND_FL)295 binode_flags |= BTRFS_INODE_APPEND;296 else297 binode_flags &= ~BTRFS_INODE_APPEND;298 if (fsflags & FS_NODUMP_FL)299 binode_flags |= BTRFS_INODE_NODUMP;300 else301 binode_flags &= ~BTRFS_INODE_NODUMP;302 if (fsflags & FS_NOATIME_FL)303 binode_flags |= BTRFS_INODE_NOATIME;304 else305 binode_flags &= ~BTRFS_INODE_NOATIME;306 307 /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */308 if (!fa->flags_valid) {309 /* 1 item for the inode */310 trans = btrfs_start_transaction(root, 1);311 if (IS_ERR(trans))312 return PTR_ERR(trans);313 goto update_flags;314 }315 316 if (fsflags & FS_DIRSYNC_FL)317 binode_flags |= BTRFS_INODE_DIRSYNC;318 else319 binode_flags &= ~BTRFS_INODE_DIRSYNC;320 if (fsflags & FS_NOCOW_FL) {321 if (S_ISREG(inode->i_mode)) {322 /*323 * It's safe to turn csums off here, no extents exist.324 * Otherwise we want the flag to reflect the real COW325 * status of the file and will not set it.326 */327 if (inode->i_size == 0)328 binode_flags |= BTRFS_INODE_NODATACOW |329 BTRFS_INODE_NODATASUM;330 } else {331 binode_flags |= BTRFS_INODE_NODATACOW;332 }333 } else {334 /*335 * Revert back under same assumptions as above336 */337 if (S_ISREG(inode->i_mode)) {338 if (inode->i_size == 0)339 binode_flags &= ~(BTRFS_INODE_NODATACOW |340 BTRFS_INODE_NODATASUM);341 } else {342 binode_flags &= ~BTRFS_INODE_NODATACOW;343 }344 }345 346 /*347 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS348 * flag may be changed automatically if compression code won't make349 * things smaller.350 */351 if (fsflags & FS_NOCOMP_FL) {352 binode_flags &= ~BTRFS_INODE_COMPRESS;353 binode_flags |= BTRFS_INODE_NOCOMPRESS;354 } else if (fsflags & FS_COMPR_FL) {355 356 if (IS_SWAPFILE(inode))357 return -ETXTBSY;358 359 binode_flags |= BTRFS_INODE_COMPRESS;360 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;361 362 comp = btrfs_compress_type2str(fs_info->compress_type);363 if (!comp || comp[0] == 0)364 comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);365 } else {366 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);367 }368 369 /*370 * 1 for inode item371 * 2 for properties372 */373 trans = btrfs_start_transaction(root, 3);374 if (IS_ERR(trans))375 return PTR_ERR(trans);376 377 if (comp) {378 ret = btrfs_set_prop(trans, BTRFS_I(inode), "btrfs.compression",379 comp, strlen(comp), 0);380 if (ret) {381 btrfs_abort_transaction(trans, ret);382 goto out_end_trans;383 }384 } else {385 ret = btrfs_set_prop(trans, BTRFS_I(inode), "btrfs.compression",386 NULL, 0, 0);387 if (ret && ret != -ENODATA) {388 btrfs_abort_transaction(trans, ret);389 goto out_end_trans;390 }391 }392 393update_flags:394 binode->flags = binode_flags;395 btrfs_sync_inode_flags_to_i_flags(inode);396 inode_inc_iversion(inode);397 inode_set_ctime_current(inode);398 ret = btrfs_update_inode(trans, BTRFS_I(inode));399 400 out_end_trans:401 btrfs_end_transaction(trans);402 return ret;403}404 405/*406 * Start exclusive operation @type, return true on success407 */408bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,409 enum btrfs_exclusive_operation type)410{411 bool ret = false;412 413 spin_lock(&fs_info->super_lock);414 if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {415 fs_info->exclusive_operation = type;416 ret = true;417 }418 spin_unlock(&fs_info->super_lock);419 420 return ret;421}422 423/*424 * Conditionally allow to enter the exclusive operation in case it's compatible425 * with the running one. This must be paired with btrfs_exclop_start_unlock and426 * btrfs_exclop_finish.427 *428 * Compatibility:429 * - the same type is already running430 * - when trying to add a device and balance has been paused431 * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller432 * must check the condition first that would allow none -> @type433 */434bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,435 enum btrfs_exclusive_operation type)436{437 spin_lock(&fs_info->super_lock);438 if (fs_info->exclusive_operation == type ||439 (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&440 type == BTRFS_EXCLOP_DEV_ADD))441 return true;442 443 spin_unlock(&fs_info->super_lock);444 return false;445}446 447void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)448{449 spin_unlock(&fs_info->super_lock);450}451 452void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)453{454 spin_lock(&fs_info->super_lock);455 WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);456 spin_unlock(&fs_info->super_lock);457 sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");458}459 460void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,461 enum btrfs_exclusive_operation op)462{463 switch (op) {464 case BTRFS_EXCLOP_BALANCE_PAUSED:465 spin_lock(&fs_info->super_lock);466 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||467 fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD ||468 fs_info->exclusive_operation == BTRFS_EXCLOP_NONE ||469 fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);470 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;471 spin_unlock(&fs_info->super_lock);472 break;473 case BTRFS_EXCLOP_BALANCE:474 spin_lock(&fs_info->super_lock);475 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);476 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;477 spin_unlock(&fs_info->super_lock);478 break;479 default:480 btrfs_warn(fs_info,481 "invalid exclop balance operation %d requested", op);482 }483}484 485static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg)486{487 return put_user(inode->i_generation, arg);488}489 490static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,491 void __user *arg)492{493 struct btrfs_device *device;494 struct fstrim_range range;495 u64 minlen = ULLONG_MAX;496 u64 num_devices = 0;497 int ret;498 499 if (!capable(CAP_SYS_ADMIN))500 return -EPERM;501 502 /*503 * btrfs_trim_block_group() depends on space cache, which is not504 * available in zoned filesystem. So, disallow fitrim on a zoned505 * filesystem for now.506 */507 if (btrfs_is_zoned(fs_info))508 return -EOPNOTSUPP;509 510 /*511 * If the fs is mounted with nologreplay, which requires it to be512 * mounted in RO mode as well, we can not allow discard on free space513 * inside block groups, because log trees refer to extents that are not514 * pinned in a block group's free space cache (pinning the extents is515 * precisely the first phase of replaying a log tree).516 */517 if (btrfs_test_opt(fs_info, NOLOGREPLAY))518 return -EROFS;519 520 rcu_read_lock();521 list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,522 dev_list) {523 if (!device->bdev || !bdev_max_discard_sectors(device->bdev))524 continue;525 num_devices++;526 minlen = min_t(u64, bdev_discard_granularity(device->bdev),527 minlen);528 }529 rcu_read_unlock();530 531 if (!num_devices)532 return -EOPNOTSUPP;533 if (copy_from_user(&range, arg, sizeof(range)))534 return -EFAULT;535 536 /*537 * NOTE: Don't truncate the range using super->total_bytes. Bytenr of538 * block group is in the logical address space, which can be any539 * sectorsize aligned bytenr in the range [0, U64_MAX].540 */541 if (range.len < fs_info->sectorsize)542 return -EINVAL;543 544 range.minlen = max(range.minlen, minlen);545 ret = btrfs_trim_fs(fs_info, &range);546 547 if (copy_to_user(arg, &range, sizeof(range)))548 return -EFAULT;549 550 return ret;551}552 553int __pure btrfs_is_empty_uuid(const u8 *uuid)554{555 int i;556 557 for (i = 0; i < BTRFS_UUID_SIZE; i++) {558 if (uuid[i])559 return 0;560 }561 return 1;562}563 564/*565 * Calculate the number of transaction items to reserve for creating a subvolume566 * or snapshot, not including the inode, directory entries, or parent directory.567 */568static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit)569{570 /*571 * 1 to add root block572 * 1 to add root item573 * 1 to add root ref574 * 1 to add root backref575 * 1 to add UUID item576 * 1 to add qgroup info577 * 1 to add qgroup limit578 *579 * Ideally the last two would only be accounted if qgroups are enabled,580 * but that can change between now and the time we would insert them.581 */582 unsigned int num_items = 7;583 584 if (inherit) {585 /* 2 to add qgroup relations for each inherited qgroup */586 num_items += 2 * inherit->num_qgroups;587 }588 return num_items;589}590 591static noinline int create_subvol(struct mnt_idmap *idmap,592 struct inode *dir, struct dentry *dentry,593 struct btrfs_qgroup_inherit *inherit)594{595 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);596 struct btrfs_trans_handle *trans;597 struct btrfs_key key;598 struct btrfs_root_item *root_item;599 struct btrfs_inode_item *inode_item;600 struct extent_buffer *leaf;601 struct btrfs_root *root = BTRFS_I(dir)->root;602 struct btrfs_root *new_root;603 struct btrfs_block_rsv block_rsv;604 struct timespec64 cur_time = current_time(dir);605 struct btrfs_new_inode_args new_inode_args = {606 .dir = dir,607 .dentry = dentry,608 .subvol = true,609 };610 unsigned int trans_num_items;611 int ret;612 dev_t anon_dev;613 u64 objectid;614 u64 qgroup_reserved = 0;615 616 root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);617 if (!root_item)618 return -ENOMEM;619 620 ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);621 if (ret)622 goto out_root_item;623 624 /*625 * Don't create subvolume whose level is not zero. Or qgroup will be626 * screwed up since it assumes subvolume qgroup's level to be 0.627 */628 if (btrfs_qgroup_level(objectid)) {629 ret = -ENOSPC;630 goto out_root_item;631 }632 633 ret = get_anon_bdev(&anon_dev);634 if (ret < 0)635 goto out_root_item;636 637 new_inode_args.inode = btrfs_new_subvol_inode(idmap, dir);638 if (!new_inode_args.inode) {639 ret = -ENOMEM;640 goto out_anon_dev;641 }642 ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);643 if (ret)644 goto out_inode;645 trans_num_items += create_subvol_num_items(inherit);646 647 btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);648 ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,649 trans_num_items, false);650 if (ret)651 goto out_new_inode_args;652 qgroup_reserved = block_rsv.qgroup_rsv_reserved;653 654 trans = btrfs_start_transaction(root, 0);655 if (IS_ERR(trans)) {656 ret = PTR_ERR(trans);657 goto out_release_rsv;658 }659 btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved);660 qgroup_reserved = 0;661 trans->block_rsv = &block_rsv;662 trans->bytes_reserved = block_rsv.size;663 664 ret = btrfs_qgroup_inherit(trans, 0, objectid, btrfs_root_id(root), inherit);665 if (ret)666 goto out;667 668 leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,669 0, BTRFS_NESTING_NORMAL);670 if (IS_ERR(leaf)) {671 ret = PTR_ERR(leaf);672 goto out;673 }674 675 btrfs_mark_buffer_dirty(trans, leaf);676 677 inode_item = &root_item->inode;678 btrfs_set_stack_inode_generation(inode_item, 1);679 btrfs_set_stack_inode_size(inode_item, 3);680 btrfs_set_stack_inode_nlink(inode_item, 1);681 btrfs_set_stack_inode_nbytes(inode_item,682 fs_info->nodesize);683 btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);684 685 btrfs_set_root_flags(root_item, 0);686 btrfs_set_root_limit(root_item, 0);687 btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);688 689 btrfs_set_root_bytenr(root_item, leaf->start);690 btrfs_set_root_generation(root_item, trans->transid);691 btrfs_set_root_level(root_item, 0);692 btrfs_set_root_refs(root_item, 1);693 btrfs_set_root_used(root_item, leaf->len);694 btrfs_set_root_last_snapshot(root_item, 0);695 696 btrfs_set_root_generation_v2(root_item,697 btrfs_root_generation(root_item));698 generate_random_guid(root_item->uuid);699 btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);700 btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);701 root_item->ctime = root_item->otime;702 btrfs_set_root_ctransid(root_item, trans->transid);703 btrfs_set_root_otransid(root_item, trans->transid);704 705 btrfs_tree_unlock(leaf);706 707 btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);708 709 key.objectid = objectid;710 key.offset = 0;711 key.type = BTRFS_ROOT_ITEM_KEY;712 ret = btrfs_insert_root(trans, fs_info->tree_root, &key,713 root_item);714 if (ret) {715 int ret2;716 717 /*718 * Since we don't abort the transaction in this case, free the719 * tree block so that we don't leak space and leave the720 * filesystem in an inconsistent state (an extent item in the721 * extent tree with a backreference for a root that does not722 * exists).723 */724 btrfs_tree_lock(leaf);725 btrfs_clear_buffer_dirty(trans, leaf);726 btrfs_tree_unlock(leaf);727 ret2 = btrfs_free_tree_block(trans, objectid, leaf, 0, 1);728 if (ret2 < 0)729 btrfs_abort_transaction(trans, ret2);730 free_extent_buffer(leaf);731 goto out;732 }733 734 free_extent_buffer(leaf);735 leaf = NULL;736 737 new_root = btrfs_get_new_fs_root(fs_info, objectid, &anon_dev);738 if (IS_ERR(new_root)) {739 ret = PTR_ERR(new_root);740 btrfs_abort_transaction(trans, ret);741 goto out;742 }743 /* anon_dev is owned by new_root now. */744 anon_dev = 0;745 BTRFS_I(new_inode_args.inode)->root = new_root;746 /* ... and new_root is owned by new_inode_args.inode now. */747 748 ret = btrfs_record_root_in_trans(trans, new_root);749 if (ret) {750 btrfs_abort_transaction(trans, ret);751 goto out;752 }753 754 ret = btrfs_uuid_tree_add(trans, root_item->uuid,755 BTRFS_UUID_KEY_SUBVOL, objectid);756 if (ret) {757 btrfs_abort_transaction(trans, ret);758 goto out;759 }760 761 ret = btrfs_create_new_inode(trans, &new_inode_args);762 if (ret) {763 btrfs_abort_transaction(trans, ret);764 goto out;765 }766 767 btrfs_record_new_subvolume(trans, BTRFS_I(dir));768 769 d_instantiate_new(dentry, new_inode_args.inode);770 new_inode_args.inode = NULL;771 772out:773 trans->block_rsv = NULL;774 trans->bytes_reserved = 0;775 btrfs_end_transaction(trans);776out_release_rsv:777 btrfs_block_rsv_release(fs_info, &block_rsv, (u64)-1, NULL);778 if (qgroup_reserved)779 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved);780out_new_inode_args:781 btrfs_new_inode_args_destroy(&new_inode_args);782out_inode:783 iput(new_inode_args.inode);784out_anon_dev:785 if (anon_dev)786 free_anon_bdev(anon_dev);787out_root_item:788 kfree(root_item);789 return ret;790}791 792static int create_snapshot(struct btrfs_root *root, struct inode *dir,793 struct dentry *dentry, bool readonly,794 struct btrfs_qgroup_inherit *inherit)795{796 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);797 struct inode *inode;798 struct btrfs_pending_snapshot *pending_snapshot;799 unsigned int trans_num_items;800 struct btrfs_trans_handle *trans;801 struct btrfs_block_rsv *block_rsv;802 u64 qgroup_reserved = 0;803 int ret;804 805 /* We do not support snapshotting right now. */806 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {807 btrfs_warn(fs_info,808 "extent tree v2 doesn't support snapshotting yet");809 return -EOPNOTSUPP;810 }811 812 if (btrfs_root_refs(&root->root_item) == 0)813 return -ENOENT;814 815 if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))816 return -EINVAL;817 818 if (atomic_read(&root->nr_swapfiles)) {819 btrfs_warn(fs_info,820 "cannot snapshot subvolume with active swapfile");821 return -ETXTBSY;822 }823 824 pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);825 if (!pending_snapshot)826 return -ENOMEM;827 828 ret = get_anon_bdev(&pending_snapshot->anon_dev);829 if (ret < 0)830 goto free_pending;831 pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),832 GFP_KERNEL);833 pending_snapshot->path = btrfs_alloc_path();834 if (!pending_snapshot->root_item || !pending_snapshot->path) {835 ret = -ENOMEM;836 goto free_pending;837 }838 839 block_rsv = &pending_snapshot->block_rsv;840 btrfs_init_block_rsv(block_rsv, BTRFS_BLOCK_RSV_TEMP);841 /*842 * 1 to add dir item843 * 1 to add dir index844 * 1 to update parent inode item845 */846 trans_num_items = create_subvol_num_items(inherit) + 3;847 ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root, block_rsv,848 trans_num_items, false);849 if (ret)850 goto free_pending;851 qgroup_reserved = block_rsv->qgroup_rsv_reserved;852 853 pending_snapshot->dentry = dentry;854 pending_snapshot->root = root;855 pending_snapshot->readonly = readonly;856 pending_snapshot->dir = BTRFS_I(dir);857 pending_snapshot->inherit = inherit;858 859 trans = btrfs_start_transaction(root, 0);860 if (IS_ERR(trans)) {861 ret = PTR_ERR(trans);862 goto fail;863 }864 ret = btrfs_record_root_in_trans(trans, BTRFS_I(dir)->root);865 if (ret) {866 btrfs_end_transaction(trans);867 goto fail;868 }869 btrfs_qgroup_convert_reserved_meta(root, qgroup_reserved);870 qgroup_reserved = 0;871 872 trans->pending_snapshot = pending_snapshot;873 874 ret = btrfs_commit_transaction(trans);875 if (ret)876 goto fail;877 878 ret = pending_snapshot->error;879 if (ret)880 goto fail;881 882 ret = btrfs_orphan_cleanup(pending_snapshot->snap);883 if (ret)884 goto fail;885 886 inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);887 if (IS_ERR(inode)) {888 ret = PTR_ERR(inode);889 goto fail;890 }891 892 d_instantiate(dentry, inode);893 ret = 0;894 pending_snapshot->anon_dev = 0;895fail:896 /* Prevent double freeing of anon_dev */897 if (ret && pending_snapshot->snap)898 pending_snapshot->snap->anon_dev = 0;899 btrfs_put_root(pending_snapshot->snap);900 btrfs_block_rsv_release(fs_info, block_rsv, (u64)-1, NULL);901 if (qgroup_reserved)902 btrfs_qgroup_free_meta_prealloc(root, qgroup_reserved);903free_pending:904 if (pending_snapshot->anon_dev)905 free_anon_bdev(pending_snapshot->anon_dev);906 kfree(pending_snapshot->root_item);907 btrfs_free_path(pending_snapshot->path);908 kfree(pending_snapshot);909 910 return ret;911}912 913/* copy of may_delete in fs/namei.c()914 * Check whether we can remove a link victim from directory dir, check915 * whether the type of victim is right.916 * 1. We can't do it if dir is read-only (done in permission())917 * 2. We should have write and exec permissions on dir918 * 3. We can't remove anything from append-only dir919 * 4. We can't do anything with immutable dir (done in permission())920 * 5. If the sticky bit on dir is set we should either921 * a. be owner of dir, or922 * b. be owner of victim, or923 * c. have CAP_FOWNER capability924 * 6. If the victim is append-only or immutable we can't do anything with925 * links pointing to it.926 * 7. If we were asked to remove a directory and victim isn't one - ENOTDIR.927 * 8. If we were asked to remove a non-directory and victim isn't one - EISDIR.928 * 9. We can't remove a root or mountpoint.929 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by930 * nfs_async_unlink().931 */932 933static int btrfs_may_delete(struct mnt_idmap *idmap,934 struct inode *dir, struct dentry *victim, int isdir)935{936 int error;937 938 if (d_really_is_negative(victim))939 return -ENOENT;940 941 /* The @victim is not inside @dir. */942 if (d_inode(victim->d_parent) != dir)943 return -EINVAL;944 audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);945 946 error = inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);947 if (error)948 return error;949 if (IS_APPEND(dir))950 return -EPERM;951 if (check_sticky(idmap, dir, d_inode(victim)) ||952 IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||953 IS_SWAPFILE(d_inode(victim)))954 return -EPERM;955 if (isdir) {956 if (!d_is_dir(victim))957 return -ENOTDIR;958 if (IS_ROOT(victim))959 return -EBUSY;960 } else if (d_is_dir(victim))961 return -EISDIR;962 if (IS_DEADDIR(dir))963 return -ENOENT;964 if (victim->d_flags & DCACHE_NFSFS_RENAMED)965 return -EBUSY;966 return 0;967}968 969/* copy of may_create in fs/namei.c() */970static inline int btrfs_may_create(struct mnt_idmap *idmap,971 struct inode *dir, struct dentry *child)972{973 if (d_really_is_positive(child))974 return -EEXIST;975 if (IS_DEADDIR(dir))976 return -ENOENT;977 if (!fsuidgid_has_mapping(dir->i_sb, idmap))978 return -EOVERFLOW;979 return inode_permission(idmap, dir, MAY_WRITE | MAY_EXEC);980}981 982/*983 * Create a new subvolume below @parent. This is largely modeled after984 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup985 * inside this filesystem so it's quite a bit simpler.986 */987static noinline int btrfs_mksubvol(const struct path *parent,988 struct mnt_idmap *idmap,989 const char *name, int namelen,990 struct btrfs_root *snap_src,991 bool readonly,992 struct btrfs_qgroup_inherit *inherit)993{994 struct inode *dir = d_inode(parent->dentry);995 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);996 struct dentry *dentry;997 struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen);998 int error;999 1000 error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);1001 if (error == -EINTR)1002 return error;1003 1004 dentry = lookup_one(idmap, name, parent->dentry, namelen);1005 error = PTR_ERR(dentry);1006 if (IS_ERR(dentry))1007 goto out_unlock;1008 1009 error = btrfs_may_create(idmap, dir, dentry);1010 if (error)1011 goto out_dput;1012 1013 /*1014 * even if this name doesn't exist, we may get hash collisions.1015 * check for them now when we can safely fail1016 */1017 error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,1018 dir->i_ino, &name_str);1019 if (error)1020 goto out_dput;1021 1022 down_read(&fs_info->subvol_sem);1023 1024 if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)1025 goto out_up_read;1026 1027 if (snap_src)1028 error = create_snapshot(snap_src, dir, dentry, readonly, inherit);1029 else1030 error = create_subvol(idmap, dir, dentry, inherit);1031 1032 if (!error)1033 fsnotify_mkdir(dir, dentry);1034out_up_read:1035 up_read(&fs_info->subvol_sem);1036out_dput:1037 dput(dentry);1038out_unlock:1039 btrfs_inode_unlock(BTRFS_I(dir), 0);1040 return error;1041}1042 1043static noinline int btrfs_mksnapshot(const struct path *parent,1044 struct mnt_idmap *idmap,1045 const char *name, int namelen,1046 struct btrfs_root *root,1047 bool readonly,1048 struct btrfs_qgroup_inherit *inherit)1049{1050 int ret;1051 bool snapshot_force_cow = false;1052 1053 /*1054 * Force new buffered writes to reserve space even when NOCOW is1055 * possible. This is to avoid later writeback (running dealloc) to1056 * fallback to COW mode and unexpectedly fail with ENOSPC.1057 */1058 btrfs_drew_read_lock(&root->snapshot_lock);1059 1060 ret = btrfs_start_delalloc_snapshot(root, false);1061 if (ret)1062 goto out;1063 1064 /*1065 * All previous writes have started writeback in NOCOW mode, so now1066 * we force future writes to fallback to COW mode during snapshot1067 * creation.1068 */1069 atomic_inc(&root->snapshot_force_cow);1070 snapshot_force_cow = true;1071 1072 btrfs_wait_ordered_extents(root, U64_MAX, NULL);1073 1074 ret = btrfs_mksubvol(parent, idmap, name, namelen,1075 root, readonly, inherit);1076out:1077 if (snapshot_force_cow)1078 atomic_dec(&root->snapshot_force_cow);1079 btrfs_drew_read_unlock(&root->snapshot_lock);1080 return ret;1081}1082 1083/*1084 * Try to start exclusive operation @type or cancel it if it's running.1085 *1086 * Return:1087 * 0 - normal mode, newly claimed op started1088 * >0 - normal mode, something else is running,1089 * return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space1090 * ECANCELED - cancel mode, successful cancel1091 * ENOTCONN - cancel mode, operation not running anymore1092 */1093static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,1094 enum btrfs_exclusive_operation type, bool cancel)1095{1096 if (!cancel) {1097 /* Start normal op */1098 if (!btrfs_exclop_start(fs_info, type))1099 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;1100 /* Exclusive operation is now claimed */1101 return 0;1102 }1103 1104 /* Cancel running op */1105 if (btrfs_exclop_start_try_lock(fs_info, type)) {1106 /*1107 * This blocks any exclop finish from setting it to NONE, so we1108 * request cancellation. Either it runs and we will wait for it,1109 * or it has finished and no waiting will happen.1110 */1111 atomic_inc(&fs_info->reloc_cancel_req);1112 btrfs_exclop_start_unlock(fs_info);1113 1114 if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))1115 wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,1116 TASK_INTERRUPTIBLE);1117 1118 return -ECANCELED;1119 }1120 1121 /* Something else is running or none */1122 return -ENOTCONN;1123}1124 1125static noinline int btrfs_ioctl_resize(struct file *file,1126 void __user *arg)1127{1128 BTRFS_DEV_LOOKUP_ARGS(args);1129 struct inode *inode = file_inode(file);1130 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);1131 u64 new_size;1132 u64 old_size;1133 u64 devid = 1;1134 struct btrfs_root *root = BTRFS_I(inode)->root;1135 struct btrfs_ioctl_vol_args *vol_args;1136 struct btrfs_trans_handle *trans;1137 struct btrfs_device *device = NULL;1138 char *sizestr;1139 char *retptr;1140 char *devstr = NULL;1141 int ret = 0;1142 int mod = 0;1143 bool cancel;1144 1145 if (!capable(CAP_SYS_ADMIN))1146 return -EPERM;1147 1148 ret = mnt_want_write_file(file);1149 if (ret)1150 return ret;1151 1152 /*1153 * Read the arguments before checking exclusivity to be able to1154 * distinguish regular resize and cancel1155 */1156 vol_args = memdup_user(arg, sizeof(*vol_args));1157 if (IS_ERR(vol_args)) {1158 ret = PTR_ERR(vol_args);1159 goto out_drop;1160 }1161 ret = btrfs_check_ioctl_vol_args_path(vol_args);1162 if (ret < 0)1163 goto out_free;1164 1165 sizestr = vol_args->name;1166 cancel = (strcmp("cancel", sizestr) == 0);1167 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);1168 if (ret)1169 goto out_free;1170 /* Exclusive operation is now claimed */1171 1172 devstr = strchr(sizestr, ':');1173 if (devstr) {1174 sizestr = devstr + 1;1175 *devstr = '\0';1176 devstr = vol_args->name;1177 ret = kstrtoull(devstr, 10, &devid);1178 if (ret)1179 goto out_finish;1180 if (!devid) {1181 ret = -EINVAL;1182 goto out_finish;1183 }1184 btrfs_info(fs_info, "resizing devid %llu", devid);1185 }1186 1187 args.devid = devid;1188 device = btrfs_find_device(fs_info->fs_devices, &args);1189 if (!device) {1190 btrfs_info(fs_info, "resizer unable to find device %llu",1191 devid);1192 ret = -ENODEV;1193 goto out_finish;1194 }1195 1196 if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {1197 btrfs_info(fs_info,1198 "resizer unable to apply on readonly device %llu",1199 devid);1200 ret = -EPERM;1201 goto out_finish;1202 }1203 1204 if (!strcmp(sizestr, "max"))1205 new_size = bdev_nr_bytes(device->bdev);1206 else {1207 if (sizestr[0] == '-') {1208 mod = -1;1209 sizestr++;1210 } else if (sizestr[0] == '+') {1211 mod = 1;1212 sizestr++;1213 }1214 new_size = memparse(sizestr, &retptr);1215 if (*retptr != '\0' || new_size == 0) {1216 ret = -EINVAL;1217 goto out_finish;1218 }1219 }1220 1221 if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {1222 ret = -EPERM;1223 goto out_finish;1224 }1225 1226 old_size = btrfs_device_get_total_bytes(device);1227 1228 if (mod < 0) {1229 if (new_size > old_size) {1230 ret = -EINVAL;1231 goto out_finish;1232 }1233 new_size = old_size - new_size;1234 } else if (mod > 0) {1235 if (new_size > ULLONG_MAX - old_size) {1236 ret = -ERANGE;1237 goto out_finish;1238 }1239 new_size = old_size + new_size;1240 }1241 1242 if (new_size < SZ_256M) {1243 ret = -EINVAL;1244 goto out_finish;1245 }1246 if (new_size > bdev_nr_bytes(device->bdev)) {1247 ret = -EFBIG;1248 goto out_finish;1249 }1250 1251 new_size = round_down(new_size, fs_info->sectorsize);1252 1253 if (new_size > old_size) {1254 trans = btrfs_start_transaction(root, 0);1255 if (IS_ERR(trans)) {1256 ret = PTR_ERR(trans);1257 goto out_finish;1258 }1259 ret = btrfs_grow_device(trans, device, new_size);1260 btrfs_commit_transaction(trans);1261 } else if (new_size < old_size) {1262 ret = btrfs_shrink_device(device, new_size);1263 } /* equal, nothing need to do */1264 1265 if (ret == 0 && new_size != old_size)1266 btrfs_info_in_rcu(fs_info,1267 "resize device %s (devid %llu) from %llu to %llu",1268 btrfs_dev_name(device), device->devid,1269 old_size, new_size);1270out_finish:1271 btrfs_exclop_finish(fs_info);1272out_free:1273 kfree(vol_args);1274out_drop:1275 mnt_drop_write_file(file);1276 return ret;1277}1278 1279static noinline int __btrfs_ioctl_snap_create(struct file *file,1280 struct mnt_idmap *idmap,1281 const char *name, unsigned long fd, int subvol,1282 bool readonly,1283 struct btrfs_qgroup_inherit *inherit)1284{1285 int namelen;1286 int ret = 0;1287 1288 if (!S_ISDIR(file_inode(file)->i_mode))1289 return -ENOTDIR;1290 1291 ret = mnt_want_write_file(file);1292 if (ret)1293 goto out;1294 1295 namelen = strlen(name);1296 if (strchr(name, '/')) {1297 ret = -EINVAL;1298 goto out_drop_write;1299 }1300 1301 if (name[0] == '.' &&1302 (namelen == 1 || (name[1] == '.' && namelen == 2))) {1303 ret = -EEXIST;1304 goto out_drop_write;1305 }1306 1307 if (subvol) {1308 ret = btrfs_mksubvol(&file->f_path, idmap, name,1309 namelen, NULL, readonly, inherit);1310 } else {1311 struct fd src = fdget(fd);1312 struct inode *src_inode;1313 if (!fd_file(src)) {1314 ret = -EINVAL;1315 goto out_drop_write;1316 }1317 1318 src_inode = file_inode(fd_file(src));1319 if (src_inode->i_sb != file_inode(file)->i_sb) {1320 btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,1321 "Snapshot src from another FS");1322 ret = -EXDEV;1323 } else if (!inode_owner_or_capable(idmap, src_inode)) {1324 /*1325 * Subvolume creation is not restricted, but snapshots1326 * are limited to own subvolumes only1327 */1328 ret = -EPERM;1329 } else if (btrfs_ino(BTRFS_I(src_inode)) != BTRFS_FIRST_FREE_OBJECTID) {1330 /*1331 * Snapshots must be made with the src_inode referring1332 * to the subvolume inode, otherwise the permission1333 * checking above is useless because we may have1334 * permission on a lower directory but not the subvol1335 * itself.1336 */1337 ret = -EINVAL;1338 } else {1339 ret = btrfs_mksnapshot(&file->f_path, idmap,1340 name, namelen,1341 BTRFS_I(src_inode)->root,1342 readonly, inherit);1343 }1344 fdput(src);1345 }1346out_drop_write:1347 mnt_drop_write_file(file);1348out:1349 return ret;1350}1351 1352static noinline int btrfs_ioctl_snap_create(struct file *file,1353 void __user *arg, int subvol)1354{1355 struct btrfs_ioctl_vol_args *vol_args;1356 int ret;1357 1358 if (!S_ISDIR(file_inode(file)->i_mode))1359 return -ENOTDIR;1360 1361 vol_args = memdup_user(arg, sizeof(*vol_args));1362 if (IS_ERR(vol_args))1363 return PTR_ERR(vol_args);1364 ret = btrfs_check_ioctl_vol_args_path(vol_args);1365 if (ret < 0)1366 goto out;1367 1368 ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),1369 vol_args->name, vol_args->fd, subvol,1370 false, NULL);1371 1372out:1373 kfree(vol_args);1374 return ret;1375}1376 1377static noinline int btrfs_ioctl_snap_create_v2(struct file *file,1378 void __user *arg, int subvol)1379{1380 struct btrfs_ioctl_vol_args_v2 *vol_args;1381 int ret;1382 bool readonly = false;1383 struct btrfs_qgroup_inherit *inherit = NULL;1384 1385 if (!S_ISDIR(file_inode(file)->i_mode))1386 return -ENOTDIR;1387 1388 vol_args = memdup_user(arg, sizeof(*vol_args));1389 if (IS_ERR(vol_args))1390 return PTR_ERR(vol_args);1391 ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args);1392 if (ret < 0)1393 goto free_args;1394 1395 if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {1396 ret = -EOPNOTSUPP;1397 goto free_args;1398 }1399 1400 if (vol_args->flags & BTRFS_SUBVOL_RDONLY)1401 readonly = true;1402 if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {1403 struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file));1404 1405 if (vol_args->size < sizeof(*inherit) ||1406 vol_args->size > PAGE_SIZE) {1407 ret = -EINVAL;1408 goto free_args;1409 }1410 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);1411 if (IS_ERR(inherit)) {1412 ret = PTR_ERR(inherit);1413 goto free_args;1414 }1415 1416 ret = btrfs_qgroup_check_inherit(fs_info, inherit, vol_args->size);1417 if (ret < 0)1418 goto free_inherit;1419 }1420 1421 ret = __btrfs_ioctl_snap_create(file, file_mnt_idmap(file),1422 vol_args->name, vol_args->fd, subvol,1423 readonly, inherit);1424 if (ret)1425 goto free_inherit;1426free_inherit:1427 kfree(inherit);1428free_args:1429 kfree(vol_args);1430 return ret;1431}1432 1433static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode,1434 void __user *arg)1435{1436 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);1437 struct btrfs_root *root = BTRFS_I(inode)->root;1438 int ret = 0;1439 u64 flags = 0;1440 1441 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)1442 return -EINVAL;1443 1444 down_read(&fs_info->subvol_sem);1445 if (btrfs_root_readonly(root))1446 flags |= BTRFS_SUBVOL_RDONLY;1447 up_read(&fs_info->subvol_sem);1448 1449 if (copy_to_user(arg, &flags, sizeof(flags)))1450 ret = -EFAULT;1451 1452 return ret;1453}1454 1455static noinline int btrfs_ioctl_subvol_setflags(struct file *file,1456 void __user *arg)1457{1458 struct inode *inode = file_inode(file);1459 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);1460 struct btrfs_root *root = BTRFS_I(inode)->root;1461 struct btrfs_trans_handle *trans;1462 u64 root_flags;1463 u64 flags;1464 int ret = 0;1465 1466 if (!inode_owner_or_capable(file_mnt_idmap(file), inode))1467 return -EPERM;1468 1469 ret = mnt_want_write_file(file);1470 if (ret)1471 goto out;1472 1473 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {1474 ret = -EINVAL;1475 goto out_drop_write;1476 }1477 1478 if (copy_from_user(&flags, arg, sizeof(flags))) {1479 ret = -EFAULT;1480 goto out_drop_write;1481 }1482 1483 if (flags & ~BTRFS_SUBVOL_RDONLY) {1484 ret = -EOPNOTSUPP;1485 goto out_drop_write;1486 }1487 1488 down_write(&fs_info->subvol_sem);1489 1490 /* nothing to do */1491 if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))1492 goto out_drop_sem;1493 1494 root_flags = btrfs_root_flags(&root->root_item);1495 if (flags & BTRFS_SUBVOL_RDONLY) {1496 btrfs_set_root_flags(&root->root_item,1497 root_flags | BTRFS_ROOT_SUBVOL_RDONLY);1498 } else {1499 /*1500 * Block RO -> RW transition if this subvolume is involved in1501 * send1502 */1503 spin_lock(&root->root_item_lock);1504 if (root->send_in_progress == 0) {1505 btrfs_set_root_flags(&root->root_item,1506 root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);1507 spin_unlock(&root->root_item_lock);1508 } else {1509 spin_unlock(&root->root_item_lock);1510 btrfs_warn(fs_info,1511 "Attempt to set subvolume %llu read-write during send",1512 btrfs_root_id(root));1513 ret = -EPERM;1514 goto out_drop_sem;1515 }1516 }1517 1518 trans = btrfs_start_transaction(root, 1);1519 if (IS_ERR(trans)) {1520 ret = PTR_ERR(trans);1521 goto out_reset;1522 }1523 1524 ret = btrfs_update_root(trans, fs_info->tree_root,1525 &root->root_key, &root->root_item);1526 if (ret < 0) {1527 btrfs_end_transaction(trans);1528 goto out_reset;1529 }1530 1531 ret = btrfs_commit_transaction(trans);1532 1533out_reset:1534 if (ret)1535 btrfs_set_root_flags(&root->root_item, root_flags);1536out_drop_sem:1537 up_write(&fs_info->subvol_sem);1538out_drop_write:1539 mnt_drop_write_file(file);1540out:1541 return ret;1542}1543 1544static noinline int key_in_sk(struct btrfs_key *key,1545 struct btrfs_ioctl_search_key *sk)1546{1547 struct btrfs_key test;1548 int ret;1549 1550 test.objectid = sk->min_objectid;1551 test.type = sk->min_type;1552 test.offset = sk->min_offset;1553 1554 ret = btrfs_comp_cpu_keys(key, &test);1555 if (ret < 0)1556 return 0;1557 1558 test.objectid = sk->max_objectid;1559 test.type = sk->max_type;1560 test.offset = sk->max_offset;1561 1562 ret = btrfs_comp_cpu_keys(key, &test);1563 if (ret > 0)1564 return 0;1565 return 1;1566}1567 1568static noinline int copy_to_sk(struct btrfs_path *path,1569 struct btrfs_key *key,1570 struct btrfs_ioctl_search_key *sk,1571 u64 *buf_size,1572 char __user *ubuf,1573 unsigned long *sk_offset,1574 int *num_found)1575{1576 u64 found_transid;1577 struct extent_buffer *leaf;1578 struct btrfs_ioctl_search_header sh;1579 struct btrfs_key test;1580 unsigned long item_off;1581 unsigned long item_len;1582 int nritems;1583 int i;1584 int slot;1585 int ret = 0;1586 1587 leaf = path->nodes[0];1588 slot = path->slots[0];1589 nritems = btrfs_header_nritems(leaf);1590 1591 if (btrfs_header_generation(leaf) > sk->max_transid) {1592 i = nritems;1593 goto advance_key;1594 }1595 found_transid = btrfs_header_generation(leaf);1596 1597 for (i = slot; i < nritems; i++) {1598 item_off = btrfs_item_ptr_offset(leaf, i);1599 item_len = btrfs_item_size(leaf, i);1600 1601 btrfs_item_key_to_cpu(leaf, key, i);1602 if (!key_in_sk(key, sk))1603 continue;1604 1605 if (sizeof(sh) + item_len > *buf_size) {1606 if (*num_found) {1607 ret = 1;1608 goto out;1609 }1610 1611 /*1612 * return one empty item back for v1, which does not1613 * handle -EOVERFLOW1614 */1615 1616 *buf_size = sizeof(sh) + item_len;1617 item_len = 0;1618 ret = -EOVERFLOW;1619 }1620 1621 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {1622 ret = 1;1623 goto out;1624 }1625 1626 sh.objectid = key->objectid;1627 sh.offset = key->offset;1628 sh.type = key->type;1629 sh.len = item_len;1630 sh.transid = found_transid;1631 1632 /*1633 * Copy search result header. If we fault then loop again so we1634 * can fault in the pages and -EFAULT there if there's a1635 * problem. Otherwise we'll fault and then copy the buffer in1636 * properly this next time through1637 */1638 if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {1639 ret = 0;1640 goto out;1641 }1642 1643 *sk_offset += sizeof(sh);1644 1645 if (item_len) {1646 char __user *up = ubuf + *sk_offset;1647 /*1648 * Copy the item, same behavior as above, but reset the1649 * * sk_offset so we copy the full thing again.1650 */1651 if (read_extent_buffer_to_user_nofault(leaf, up,1652 item_off, item_len)) {1653 ret = 0;1654 *sk_offset -= sizeof(sh);1655 goto out;1656 }1657 1658 *sk_offset += item_len;1659 }1660 (*num_found)++;1661 1662 if (ret) /* -EOVERFLOW from above */1663 goto out;1664 1665 if (*num_found >= sk->nr_items) {1666 ret = 1;1667 goto out;1668 }1669 }1670advance_key:1671 ret = 0;1672 test.objectid = sk->max_objectid;1673 test.type = sk->max_type;1674 test.offset = sk->max_offset;1675 if (btrfs_comp_cpu_keys(key, &test) >= 0)1676 ret = 1;1677 else if (key->offset < (u64)-1)1678 key->offset++;1679 else if (key->type < (u8)-1) {1680 key->offset = 0;1681 key->type++;1682 } else if (key->objectid < (u64)-1) {1683 key->offset = 0;1684 key->type = 0;1685 key->objectid++;1686 } else1687 ret = 1;1688out:1689 /*1690 * 0: all items from this leaf copied, continue with next1691 * 1: * more items can be copied, but unused buffer is too small1692 * * all items were found1693 * Either way, it will stops the loop which iterates to the next1694 * leaf1695 * -EOVERFLOW: item was to large for buffer1696 * -EFAULT: could not copy extent buffer back to userspace1697 */1698 return ret;1699}1700 1701static noinline int search_ioctl(struct inode *inode,1702 struct btrfs_ioctl_search_key *sk,1703 u64 *buf_size,1704 char __user *ubuf)1705{1706 struct btrfs_fs_info *info = inode_to_fs_info(inode);1707 struct btrfs_root *root;1708 struct btrfs_key key;1709 struct btrfs_path *path;1710 int ret;1711 int num_found = 0;1712 unsigned long sk_offset = 0;1713 1714 if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {1715 *buf_size = sizeof(struct btrfs_ioctl_search_header);1716 return -EOVERFLOW;1717 }1718 1719 path = btrfs_alloc_path();1720 if (!path)1721 return -ENOMEM;1722 1723 if (sk->tree_id == 0) {1724 /* search the root of the inode that was passed */1725 root = btrfs_grab_root(BTRFS_I(inode)->root);1726 } else {1727 root = btrfs_get_fs_root(info, sk->tree_id, true);1728 if (IS_ERR(root)) {1729 btrfs_free_path(path);1730 return PTR_ERR(root);1731 }1732 }1733 1734 key.objectid = sk->min_objectid;1735 key.type = sk->min_type;1736 key.offset = sk->min_offset;1737 1738 while (1) {1739 ret = -EFAULT;1740 /*1741 * Ensure that the whole user buffer is faulted in at sub-page1742 * granularity, otherwise the loop may live-lock.1743 */1744 if (fault_in_subpage_writeable(ubuf + sk_offset,1745 *buf_size - sk_offset))1746 break;1747 1748 ret = btrfs_search_forward(root, &key, path, sk->min_transid);1749 if (ret != 0) {1750 if (ret > 0)1751 ret = 0;1752 goto err;1753 }1754 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,1755 &sk_offset, &num_found);1756 btrfs_release_path(path);1757 if (ret)1758 break;1759 1760 }1761 if (ret > 0)1762 ret = 0;1763err:1764 sk->nr_items = num_found;1765 btrfs_put_root(root);1766 btrfs_free_path(path);1767 return ret;1768}1769 1770static noinline int btrfs_ioctl_tree_search(struct inode *inode,1771 void __user *argp)1772{1773 struct btrfs_ioctl_search_args __user *uargs = argp;1774 struct btrfs_ioctl_search_key sk;1775 int ret;1776 u64 buf_size;1777 1778 if (!capable(CAP_SYS_ADMIN))1779 return -EPERM;1780 1781 if (copy_from_user(&sk, &uargs->key, sizeof(sk)))1782 return -EFAULT;1783 1784 buf_size = sizeof(uargs->buf);1785 1786 ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);1787 1788 /*1789 * In the origin implementation an overflow is handled by returning a1790 * search header with a len of zero, so reset ret.1791 */1792 if (ret == -EOVERFLOW)1793 ret = 0;1794 1795 if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))1796 ret = -EFAULT;1797 return ret;1798}1799 1800static noinline int btrfs_ioctl_tree_search_v2(struct inode *inode,1801 void __user *argp)1802{1803 struct btrfs_ioctl_search_args_v2 __user *uarg = argp;1804 struct btrfs_ioctl_search_args_v2 args;1805 int ret;1806 u64 buf_size;1807 const u64 buf_limit = SZ_16M;1808 1809 if (!capable(CAP_SYS_ADMIN))1810 return -EPERM;1811 1812 /* copy search header and buffer size */1813 if (copy_from_user(&args, uarg, sizeof(args)))1814 return -EFAULT;1815 1816 buf_size = args.buf_size;1817 1818 /* limit result size to 16MB */1819 if (buf_size > buf_limit)1820 buf_size = buf_limit;1821 1822 ret = search_ioctl(inode, &args.key, &buf_size,1823 (char __user *)(&uarg->buf[0]));1824 if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))1825 ret = -EFAULT;1826 else if (ret == -EOVERFLOW &&1827 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))1828 ret = -EFAULT;1829 1830 return ret;1831}1832 1833/*1834 * Search INODE_REFs to identify path name of 'dirid' directory1835 * in a 'tree_id' tree. and sets path name to 'name'.1836 */1837static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,1838 u64 tree_id, u64 dirid, char *name)1839{1840 struct btrfs_root *root;1841 struct btrfs_key key;1842 char *ptr;1843 int ret = -1;1844 int slot;1845 int len;1846 int total_len = 0;1847 struct btrfs_inode_ref *iref;1848 struct extent_buffer *l;1849 struct btrfs_path *path;1850 1851 if (dirid == BTRFS_FIRST_FREE_OBJECTID) {1852 name[0]='\0';1853 return 0;1854 }1855 1856 path = btrfs_alloc_path();1857 if (!path)1858 return -ENOMEM;1859 1860 ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];1861 1862 root = btrfs_get_fs_root(info, tree_id, true);1863 if (IS_ERR(root)) {1864 ret = PTR_ERR(root);1865 root = NULL;1866 goto out;1867 }1868 1869 key.objectid = dirid;1870 key.type = BTRFS_INODE_REF_KEY;1871 key.offset = (u64)-1;1872 1873 while (1) {1874 ret = btrfs_search_backwards(root, &key, path);1875 if (ret < 0)1876 goto out;1877 else if (ret > 0) {1878 ret = -ENOENT;1879 goto out;1880 }1881 1882 l = path->nodes[0];1883 slot = path->slots[0];1884 1885 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);1886 len = btrfs_inode_ref_name_len(l, iref);1887 ptr -= len + 1;1888 total_len += len + 1;1889 if (ptr < name) {1890 ret = -ENAMETOOLONG;1891 goto out;1892 }1893 1894 *(ptr + len) = '/';1895 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);1896 1897 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)1898 break;1899 1900 btrfs_release_path(path);1901 key.objectid = key.offset;1902 key.offset = (u64)-1;1903 dirid = key.objectid;1904 }1905 memmove(name, ptr, total_len);1906 name[total_len] = '\0';1907 ret = 0;1908out:1909 btrfs_put_root(root);1910 btrfs_free_path(path);1911 return ret;1912}1913 1914static int btrfs_search_path_in_tree_user(struct mnt_idmap *idmap,1915 struct inode *inode,1916 struct btrfs_ioctl_ino_lookup_user_args *args)1917{1918 struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;1919 u64 upper_limit = btrfs_ino(BTRFS_I(inode));1920 u64 treeid = btrfs_root_id(BTRFS_I(inode)->root);1921 u64 dirid = args->dirid;1922 unsigned long item_off;1923 unsigned long item_len;1924 struct btrfs_inode_ref *iref;1925 struct btrfs_root_ref *rref;1926 struct btrfs_root *root = NULL;1927 struct btrfs_path *path;1928 struct btrfs_key key, key2;1929 struct extent_buffer *leaf;1930 struct inode *temp_inode;1931 char *ptr;1932 int slot;1933 int len;1934 int total_len = 0;1935 int ret;1936 1937 path = btrfs_alloc_path();1938 if (!path)1939 return -ENOMEM;1940 1941 /*1942 * If the bottom subvolume does not exist directly under upper_limit,1943 * construct the path in from the bottom up.1944 */1945 if (dirid != upper_limit) {1946 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];1947 1948 root = btrfs_get_fs_root(fs_info, treeid, true);1949 if (IS_ERR(root)) {1950 ret = PTR_ERR(root);1951 goto out;1952 }1953 1954 key.objectid = dirid;1955 key.type = BTRFS_INODE_REF_KEY;1956 key.offset = (u64)-1;1957 while (1) {1958 ret = btrfs_search_backwards(root, &key, path);1959 if (ret < 0)1960 goto out_put;1961 else if (ret > 0) {1962 ret = -ENOENT;1963 goto out_put;1964 }1965 1966 leaf = path->nodes[0];1967 slot = path->slots[0];1968 1969 iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);1970 len = btrfs_inode_ref_name_len(leaf, iref);1971 ptr -= len + 1;1972 total_len += len + 1;1973 if (ptr < args->path) {1974 ret = -ENAMETOOLONG;1975 goto out_put;1976 }1977 1978 *(ptr + len) = '/';1979 read_extent_buffer(leaf, ptr,1980 (unsigned long)(iref + 1), len);1981 1982 /* Check the read+exec permission of this directory */1983 ret = btrfs_previous_item(root, path, dirid,1984 BTRFS_INODE_ITEM_KEY);1985 if (ret < 0) {1986 goto out_put;1987 } else if (ret > 0) {1988 ret = -ENOENT;1989 goto out_put;1990 }1991 1992 leaf = path->nodes[0];1993 slot = path->slots[0];1994 btrfs_item_key_to_cpu(leaf, &key2, slot);1995 if (key2.objectid != dirid) {1996 ret = -ENOENT;1997 goto out_put;1998 }1999 2000 /*2001 * We don't need the path anymore, so release it and2002 * avoid deadlocks and lockdep warnings in case2003 * btrfs_iget() needs to lookup the inode from its root2004 * btree and lock the same leaf.2005 */2006 btrfs_release_path(path);2007 temp_inode = btrfs_iget(key2.objectid, root);2008 if (IS_ERR(temp_inode)) {2009 ret = PTR_ERR(temp_inode);2010 goto out_put;2011 }2012 ret = inode_permission(idmap, temp_inode,2013 MAY_READ | MAY_EXEC);2014 iput(temp_inode);2015 if (ret) {2016 ret = -EACCES;2017 goto out_put;2018 }2019 2020 if (key.offset == upper_limit)2021 break;2022 if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {2023 ret = -EACCES;2024 goto out_put;2025 }2026 2027 key.objectid = key.offset;2028 key.offset = (u64)-1;2029 dirid = key.objectid;2030 }2031 2032 memmove(args->path, ptr, total_len);2033 args->path[total_len] = '\0';2034 btrfs_put_root(root);2035 root = NULL;2036 btrfs_release_path(path);2037 }2038 2039 /* Get the bottom subvolume's name from ROOT_REF */2040 key.objectid = treeid;2041 key.type = BTRFS_ROOT_REF_KEY;2042 key.offset = args->treeid;2043 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);2044 if (ret < 0) {2045 goto out;2046 } else if (ret > 0) {2047 ret = -ENOENT;2048 goto out;2049 }2050 2051 leaf = path->nodes[0];2052 slot = path->slots[0];2053 btrfs_item_key_to_cpu(leaf, &key, slot);2054 2055 item_off = btrfs_item_ptr_offset(leaf, slot);2056 item_len = btrfs_item_size(leaf, slot);2057 /* Check if dirid in ROOT_REF corresponds to passed dirid */2058 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);2059 if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {2060 ret = -EINVAL;2061 goto out;2062 }2063 2064 /* Copy subvolume's name */2065 item_off += sizeof(struct btrfs_root_ref);2066 item_len -= sizeof(struct btrfs_root_ref);2067 read_extent_buffer(leaf, args->name, item_off, item_len);2068 args->name[item_len] = 0;2069 2070out_put:2071 btrfs_put_root(root);2072out:2073 btrfs_free_path(path);2074 return ret;2075}2076 2077static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root,2078 void __user *argp)2079{2080 struct btrfs_ioctl_ino_lookup_args *args;2081 int ret = 0;2082 2083 args = memdup_user(argp, sizeof(*args));2084 if (IS_ERR(args))2085 return PTR_ERR(args);2086 2087 /*2088 * Unprivileged query to obtain the containing subvolume root id. The2089 * path is reset so it's consistent with btrfs_search_path_in_tree.2090 */2091 if (args->treeid == 0)2092 args->treeid = btrfs_root_id(root);2093 2094 if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {2095 args->name[0] = 0;2096 goto out;2097 }2098 2099 if (!capable(CAP_SYS_ADMIN)) {2100 ret = -EPERM;2101 goto out;2102 }2103 2104 ret = btrfs_search_path_in_tree(root->fs_info,2105 args->treeid, args->objectid,2106 args->name);2107 2108out:2109 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))2110 ret = -EFAULT;2111 2112 kfree(args);2113 return ret;2114}2115 2116/*2117 * Version of ino_lookup ioctl (unprivileged)2118 *2119 * The main differences from ino_lookup ioctl are:2120 *2121 * 1. Read + Exec permission will be checked using inode_permission() during2122 * path construction. -EACCES will be returned in case of failure.2123 * 2. Path construction will be stopped at the inode number which corresponds2124 * to the fd with which this ioctl is called. If constructed path does not2125 * exist under fd's inode, -EACCES will be returned.2126 * 3. The name of bottom subvolume is also searched and filled.2127 */2128static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)2129{2130 struct btrfs_ioctl_ino_lookup_user_args *args;2131 struct inode *inode;2132 int ret;2133 2134 args = memdup_user(argp, sizeof(*args));2135 if (IS_ERR(args))2136 return PTR_ERR(args);2137 2138 inode = file_inode(file);2139 2140 if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&2141 btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {2142 /*2143 * The subvolume does not exist under fd with which this is2144 * called2145 */2146 kfree(args);2147 return -EACCES;2148 }2149 2150 ret = btrfs_search_path_in_tree_user(file_mnt_idmap(file), inode, args);2151 2152 if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))2153 ret = -EFAULT;2154 2155 kfree(args);2156 return ret;2157}2158 2159/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */2160static int btrfs_ioctl_get_subvol_info(struct inode *inode, void __user *argp)2161{2162 struct btrfs_ioctl_get_subvol_info_args *subvol_info;2163 struct btrfs_fs_info *fs_info;2164 struct btrfs_root *root;2165 struct btrfs_path *path;2166 struct btrfs_key key;2167 struct btrfs_root_item *root_item;2168 struct btrfs_root_ref *rref;2169 struct extent_buffer *leaf;2170 unsigned long item_off;2171 unsigned long item_len;2172 int slot;2173 int ret = 0;2174 2175 path = btrfs_alloc_path();2176 if (!path)2177 return -ENOMEM;2178 2179 subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);2180 if (!subvol_info) {2181 btrfs_free_path(path);2182 return -ENOMEM;2183 }2184 2185 fs_info = BTRFS_I(inode)->root->fs_info;2186 2187 /* Get root_item of inode's subvolume */2188 key.objectid = btrfs_root_id(BTRFS_I(inode)->root);2189 root = btrfs_get_fs_root(fs_info, key.objectid, true);2190 if (IS_ERR(root)) {2191 ret = PTR_ERR(root);2192 goto out_free;2193 }2194 root_item = &root->root_item;2195 2196 subvol_info->treeid = key.objectid;2197 2198 subvol_info->generation = btrfs_root_generation(root_item);2199 subvol_info->flags = btrfs_root_flags(root_item);2200 2201 memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);2202 memcpy(subvol_info->parent_uuid, root_item->parent_uuid,2203 BTRFS_UUID_SIZE);2204 memcpy(subvol_info->received_uuid, root_item->received_uuid,2205 BTRFS_UUID_SIZE);2206 2207 subvol_info->ctransid = btrfs_root_ctransid(root_item);2208 subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);2209 subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);2210 2211 subvol_info->otransid = btrfs_root_otransid(root_item);2212 subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);2213 subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);2214 2215 subvol_info->stransid = btrfs_root_stransid(root_item);2216 subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);2217 subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);2218 2219 subvol_info->rtransid = btrfs_root_rtransid(root_item);2220 subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);2221 subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);2222 2223 if (key.objectid != BTRFS_FS_TREE_OBJECTID) {2224 /* Search root tree for ROOT_BACKREF of this subvolume */2225 key.type = BTRFS_ROOT_BACKREF_KEY;2226 key.offset = 0;2227 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);2228 if (ret < 0) {2229 goto out;2230 } else if (path->slots[0] >=2231 btrfs_header_nritems(path->nodes[0])) {2232 ret = btrfs_next_leaf(fs_info->tree_root, path);2233 if (ret < 0) {2234 goto out;2235 } else if (ret > 0) {2236 ret = -EUCLEAN;2237 goto out;2238 }2239 }2240 2241 leaf = path->nodes[0];2242 slot = path->slots[0];2243 btrfs_item_key_to_cpu(leaf, &key, slot);2244 if (key.objectid == subvol_info->treeid &&2245 key.type == BTRFS_ROOT_BACKREF_KEY) {2246 subvol_info->parent_id = key.offset;2247 2248 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);2249 subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);2250 2251 item_off = btrfs_item_ptr_offset(leaf, slot)2252 + sizeof(struct btrfs_root_ref);2253 item_len = btrfs_item_size(leaf, slot)2254 - sizeof(struct btrfs_root_ref);2255 read_extent_buffer(leaf, subvol_info->name,2256 item_off, item_len);2257 } else {2258 ret = -ENOENT;2259 goto out;2260 }2261 }2262 2263 btrfs_free_path(path);2264 path = NULL;2265 if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))2266 ret = -EFAULT;2267 2268out:2269 btrfs_put_root(root);2270out_free:2271 btrfs_free_path(path);2272 kfree(subvol_info);2273 return ret;2274}2275 2276/*2277 * Return ROOT_REF information of the subvolume containing this inode2278 * except the subvolume name.2279 */2280static int btrfs_ioctl_get_subvol_rootref(struct btrfs_root *root,2281 void __user *argp)2282{2283 struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;2284 struct btrfs_root_ref *rref;2285 struct btrfs_path *path;2286 struct btrfs_key key;2287 struct extent_buffer *leaf;2288 u64 objectid;2289 int slot;2290 int ret;2291 u8 found;2292 2293 path = btrfs_alloc_path();2294 if (!path)2295 return -ENOMEM;2296 2297 rootrefs = memdup_user(argp, sizeof(*rootrefs));2298 if (IS_ERR(rootrefs)) {2299 btrfs_free_path(path);2300 return PTR_ERR(rootrefs);2301 }2302 2303 objectid = btrfs_root_id(root);2304 key.objectid = objectid;2305 key.type = BTRFS_ROOT_REF_KEY;2306 key.offset = rootrefs->min_treeid;2307 found = 0;2308 2309 root = root->fs_info->tree_root;2310 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);2311 if (ret < 0) {2312 goto out;2313 } else if (path->slots[0] >=2314 btrfs_header_nritems(path->nodes[0])) {2315 ret = btrfs_next_leaf(root, path);2316 if (ret < 0) {2317 goto out;2318 } else if (ret > 0) {2319 ret = -EUCLEAN;2320 goto out;2321 }2322 }2323 while (1) {2324 leaf = path->nodes[0];2325 slot = path->slots[0];2326 2327 btrfs_item_key_to_cpu(leaf, &key, slot);2328 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {2329 ret = 0;2330 goto out;2331 }2332 2333 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {2334 ret = -EOVERFLOW;2335 goto out;2336 }2337 2338 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);2339 rootrefs->rootref[found].treeid = key.offset;2340 rootrefs->rootref[found].dirid =2341 btrfs_root_ref_dirid(leaf, rref);2342 found++;2343 2344 ret = btrfs_next_item(root, path);2345 if (ret < 0) {2346 goto out;2347 } else if (ret > 0) {2348 ret = -EUCLEAN;2349 goto out;2350 }2351 }2352 2353out:2354 btrfs_free_path(path);2355 2356 if (!ret || ret == -EOVERFLOW) {2357 rootrefs->num_items = found;2358 /* update min_treeid for next search */2359 if (found)2360 rootrefs->min_treeid =2361 rootrefs->rootref[found - 1].treeid + 1;2362 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))2363 ret = -EFAULT;2364 }2365 2366 kfree(rootrefs);2367 2368 return ret;2369}2370 2371static noinline int btrfs_ioctl_snap_destroy(struct file *file,2372 void __user *arg,2373 bool destroy_v2)2374{2375 struct dentry *parent = file->f_path.dentry;2376 struct dentry *dentry;2377 struct inode *dir = d_inode(parent);2378 struct btrfs_fs_info *fs_info = inode_to_fs_info(dir);2379 struct inode *inode;2380 struct btrfs_root *root = BTRFS_I(dir)->root;2381 struct btrfs_root *dest = NULL;2382 struct btrfs_ioctl_vol_args *vol_args = NULL;2383 struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;2384 struct mnt_idmap *idmap = file_mnt_idmap(file);2385 char *subvol_name, *subvol_name_ptr = NULL;2386 int subvol_namelen;2387 int ret = 0;2388 bool destroy_parent = false;2389 2390 /* We don't support snapshots with extent tree v2 yet. */2391 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {2392 btrfs_err(fs_info,2393 "extent tree v2 doesn't support snapshot deletion yet");2394 return -EOPNOTSUPP;2395 }2396 2397 if (destroy_v2) {2398 vol_args2 = memdup_user(arg, sizeof(*vol_args2));2399 if (IS_ERR(vol_args2))2400 return PTR_ERR(vol_args2);2401 2402 if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {2403 ret = -EOPNOTSUPP;2404 goto out;2405 }2406 2407 /*2408 * If SPEC_BY_ID is not set, we are looking for the subvolume by2409 * name, same as v1 currently does.2410 */2411 if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {2412 ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args2);2413 if (ret < 0)2414 goto out;2415 subvol_name = vol_args2->name;2416 2417 ret = mnt_want_write_file(file);2418 if (ret)2419 goto out;2420 } else {2421 struct inode *old_dir;2422 2423 if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {2424 ret = -EINVAL;2425 goto out;2426 }2427 2428 ret = mnt_want_write_file(file);2429 if (ret)2430 goto out;2431 2432 dentry = btrfs_get_dentry(fs_info->sb,2433 BTRFS_FIRST_FREE_OBJECTID,2434 vol_args2->subvolid, 0);2435 if (IS_ERR(dentry)) {2436 ret = PTR_ERR(dentry);2437 goto out_drop_write;2438 }2439 2440 /*2441 * Change the default parent since the subvolume being2442 * deleted can be outside of the current mount point.2443 */2444 parent = btrfs_get_parent(dentry);2445 2446 /*2447 * At this point dentry->d_name can point to '/' if the2448 * subvolume we want to destroy is outsite of the2449 * current mount point, so we need to release the2450 * current dentry and execute the lookup to return a new2451 * one with ->d_name pointing to the2452 * <mount point>/subvol_name.2453 */2454 dput(dentry);2455 if (IS_ERR(parent)) {2456 ret = PTR_ERR(parent);2457 goto out_drop_write;2458 }2459 old_dir = dir;2460 dir = d_inode(parent);2461 2462 /*2463 * If v2 was used with SPEC_BY_ID, a new parent was2464 * allocated since the subvolume can be outside of the2465 * current mount point. Later on we need to release this2466 * new parent dentry.2467 */2468 destroy_parent = true;2469 2470 /*2471 * On idmapped mounts, deletion via subvolid is2472 * restricted to subvolumes that are immediate2473 * ancestors of the inode referenced by the file2474 * descriptor in the ioctl. Otherwise the idmapping2475 * could potentially be abused to delete subvolumes2476 * anywhere in the filesystem the user wouldn't be able2477 * to delete without an idmapped mount.2478 */2479 if (old_dir != dir && idmap != &nop_mnt_idmap) {2480 ret = -EOPNOTSUPP;2481 goto free_parent;2482 }2483 2484 subvol_name_ptr = btrfs_get_subvol_name_from_objectid(2485 fs_info, vol_args2->subvolid);2486 if (IS_ERR(subvol_name_ptr)) {2487 ret = PTR_ERR(subvol_name_ptr);2488 goto free_parent;2489 }2490 /* subvol_name_ptr is already nul terminated */2491 subvol_name = (char *)kbasename(subvol_name_ptr);2492 }2493 } else {2494 vol_args = memdup_user(arg, sizeof(*vol_args));2495 if (IS_ERR(vol_args))2496 return PTR_ERR(vol_args);2497 2498 ret = btrfs_check_ioctl_vol_args_path(vol_args);2499 if (ret < 0)2500 goto out;2501 2502 subvol_name = vol_args->name;2503 2504 ret = mnt_want_write_file(file);2505 if (ret)2506 goto out;2507 }2508 2509 subvol_namelen = strlen(subvol_name);2510 2511 if (strchr(subvol_name, '/') ||2512 strncmp(subvol_name, "..", subvol_namelen) == 0) {2513 ret = -EINVAL;2514 goto free_subvol_name;2515 }2516 2517 if (!S_ISDIR(dir->i_mode)) {2518 ret = -ENOTDIR;2519 goto free_subvol_name;2520 }2521 2522 ret = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);2523 if (ret == -EINTR)2524 goto free_subvol_name;2525 dentry = lookup_one(idmap, subvol_name, parent, subvol_namelen);2526 if (IS_ERR(dentry)) {2527 ret = PTR_ERR(dentry);2528 goto out_unlock_dir;2529 }2530 2531 if (d_really_is_negative(dentry)) {2532 ret = -ENOENT;2533 goto out_dput;2534 }2535 2536 inode = d_inode(dentry);2537 dest = BTRFS_I(inode)->root;2538 if (!capable(CAP_SYS_ADMIN)) {2539 /*2540 * Regular user. Only allow this with a special mount2541 * option, when the user has write+exec access to the2542 * subvol root, and when rmdir(2) would have been2543 * allowed.2544 *2545 * Note that this is _not_ check that the subvol is2546 * empty or doesn't contain data that we wouldn't2547 * otherwise be able to delete.2548 *2549 * Users who want to delete empty subvols should try2550 * rmdir(2).2551 */2552 ret = -EPERM;2553 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))2554 goto out_dput;2555 2556 /*2557 * Do not allow deletion if the parent dir is the same2558 * as the dir to be deleted. That means the ioctl2559 * must be called on the dentry referencing the root2560 * of the subvol, not a random directory contained2561 * within it.2562 */2563 ret = -EINVAL;2564 if (root == dest)2565 goto out_dput;2566 2567 ret = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC);2568 if (ret)2569 goto out_dput;2570 }2571 2572 /* check if subvolume may be deleted by a user */2573 ret = btrfs_may_delete(idmap, dir, dentry, 1);2574 if (ret)2575 goto out_dput;2576 2577 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {2578 ret = -EINVAL;2579 goto out_dput;2580 }2581 2582 btrfs_inode_lock(BTRFS_I(inode), 0);2583 ret = btrfs_delete_subvolume(BTRFS_I(dir), dentry);2584 btrfs_inode_unlock(BTRFS_I(inode), 0);2585 if (!ret)2586 d_delete_notify(dir, dentry);2587 2588out_dput:2589 dput(dentry);2590out_unlock_dir:2591 btrfs_inode_unlock(BTRFS_I(dir), 0);2592free_subvol_name:2593 kfree(subvol_name_ptr);2594free_parent:2595 if (destroy_parent)2596 dput(parent);2597out_drop_write:2598 mnt_drop_write_file(file);2599out:2600 kfree(vol_args2);2601 kfree(vol_args);2602 return ret;2603}2604 2605static int btrfs_ioctl_defrag(struct file *file, void __user *argp)2606{2607 struct inode *inode = file_inode(file);2608 struct btrfs_root *root = BTRFS_I(inode)->root;2609 struct btrfs_ioctl_defrag_range_args range = {0};2610 int ret;2611 2612 ret = mnt_want_write_file(file);2613 if (ret)2614 return ret;2615 2616 if (btrfs_root_readonly(root)) {2617 ret = -EROFS;2618 goto out;2619 }2620 2621 switch (inode->i_mode & S_IFMT) {2622 case S_IFDIR:2623 if (!capable(CAP_SYS_ADMIN)) {2624 ret = -EPERM;2625 goto out;2626 }2627 ret = btrfs_defrag_root(root);2628 break;2629 case S_IFREG:2630 /*2631 * Note that this does not check the file descriptor for write2632 * access. This prevents defragmenting executables that are2633 * running and allows defrag on files open in read-only mode.2634 */2635 if (!capable(CAP_SYS_ADMIN) &&2636 inode_permission(&nop_mnt_idmap, inode, MAY_WRITE)) {2637 ret = -EPERM;2638 goto out;2639 }2640 2641 if (argp) {2642 if (copy_from_user(&range, argp, sizeof(range))) {2643 ret = -EFAULT;2644 goto out;2645 }2646 if (range.flags & ~BTRFS_DEFRAG_RANGE_FLAGS_SUPP) {2647 ret = -EOPNOTSUPP;2648 goto out;2649 }2650 /* compression requires us to start the IO */2651 if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {2652 range.flags |= BTRFS_DEFRAG_RANGE_START_IO;2653 range.extent_thresh = (u32)-1;2654 }2655 } else {2656 /* the rest are all set to zero by kzalloc */2657 range.len = (u64)-1;2658 }2659 ret = btrfs_defrag_file(file_inode(file), &file->f_ra,2660 &range, BTRFS_OLDEST_GENERATION, 0);2661 if (ret > 0)2662 ret = 0;2663 break;2664 default:2665 ret = -EINVAL;2666 }2667out:2668 mnt_drop_write_file(file);2669 return ret;2670}2671 2672static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)2673{2674 struct btrfs_ioctl_vol_args *vol_args;2675 bool restore_op = false;2676 int ret;2677 2678 if (!capable(CAP_SYS_ADMIN))2679 return -EPERM;2680 2681 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {2682 btrfs_err(fs_info, "device add not supported on extent tree v2 yet");2683 return -EINVAL;2684 }2685 2686 if (fs_info->fs_devices->temp_fsid) {2687 btrfs_err(fs_info,2688 "device add not supported on cloned temp-fsid mount");2689 return -EINVAL;2690 }2691 2692 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {2693 if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))2694 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;2695 2696 /*2697 * We can do the device add because we have a paused balanced,2698 * change the exclusive op type and remember we should bring2699 * back the paused balance2700 */2701 fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;2702 btrfs_exclop_start_unlock(fs_info);2703 restore_op = true;2704 }2705 2706 vol_args = memdup_user(arg, sizeof(*vol_args));2707 if (IS_ERR(vol_args)) {2708 ret = PTR_ERR(vol_args);2709 goto out;2710 }2711 2712 ret = btrfs_check_ioctl_vol_args_path(vol_args);2713 if (ret < 0)2714 goto out_free;2715 2716 ret = btrfs_init_new_device(fs_info, vol_args->name);2717 2718 if (!ret)2719 btrfs_info(fs_info, "disk added %s", vol_args->name);2720 2721out_free:2722 kfree(vol_args);2723out:2724 if (restore_op)2725 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);2726 else2727 btrfs_exclop_finish(fs_info);2728 return ret;2729}2730 2731static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)2732{2733 BTRFS_DEV_LOOKUP_ARGS(args);2734 struct inode *inode = file_inode(file);2735 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);2736 struct btrfs_ioctl_vol_args_v2 *vol_args;2737 struct file *bdev_file = NULL;2738 int ret;2739 bool cancel = false;2740 2741 if (!capable(CAP_SYS_ADMIN))2742 return -EPERM;2743 2744 vol_args = memdup_user(arg, sizeof(*vol_args));2745 if (IS_ERR(vol_args))2746 return PTR_ERR(vol_args);2747 2748 if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {2749 ret = -EOPNOTSUPP;2750 goto out;2751 }2752 2753 ret = btrfs_check_ioctl_vol_args2_subvol_name(vol_args);2754 if (ret < 0)2755 goto out;2756 2757 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {2758 args.devid = vol_args->devid;2759 } else if (!strcmp("cancel", vol_args->name)) {2760 cancel = true;2761 } else {2762 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);2763 if (ret)2764 goto out;2765 }2766 2767 ret = mnt_want_write_file(file);2768 if (ret)2769 goto out;2770 2771 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,2772 cancel);2773 if (ret)2774 goto err_drop;2775 2776 /* Exclusive operation is now claimed */2777 ret = btrfs_rm_device(fs_info, &args, &bdev_file);2778 2779 btrfs_exclop_finish(fs_info);2780 2781 if (!ret) {2782 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)2783 btrfs_info(fs_info, "device deleted: id %llu",2784 vol_args->devid);2785 else2786 btrfs_info(fs_info, "device deleted: %s",2787 vol_args->name);2788 }2789err_drop:2790 mnt_drop_write_file(file);2791 if (bdev_file)2792 fput(bdev_file);2793out:2794 btrfs_put_dev_args_from_path(&args);2795 kfree(vol_args);2796 return ret;2797}2798 2799static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)2800{2801 BTRFS_DEV_LOOKUP_ARGS(args);2802 struct inode *inode = file_inode(file);2803 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);2804 struct btrfs_ioctl_vol_args *vol_args;2805 struct file *bdev_file = NULL;2806 int ret;2807 bool cancel = false;2808 2809 if (!capable(CAP_SYS_ADMIN))2810 return -EPERM;2811 2812 vol_args = memdup_user(arg, sizeof(*vol_args));2813 if (IS_ERR(vol_args))2814 return PTR_ERR(vol_args);2815 2816 ret = btrfs_check_ioctl_vol_args_path(vol_args);2817 if (ret < 0)2818 goto out_free;2819 2820 if (!strcmp("cancel", vol_args->name)) {2821 cancel = true;2822 } else {2823 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);2824 if (ret)2825 goto out;2826 }2827 2828 ret = mnt_want_write_file(file);2829 if (ret)2830 goto out;2831 2832 ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,2833 cancel);2834 if (ret == 0) {2835 ret = btrfs_rm_device(fs_info, &args, &bdev_file);2836 if (!ret)2837 btrfs_info(fs_info, "disk deleted %s", vol_args->name);2838 btrfs_exclop_finish(fs_info);2839 }2840 2841 mnt_drop_write_file(file);2842 if (bdev_file)2843 fput(bdev_file);2844out:2845 btrfs_put_dev_args_from_path(&args);2846out_free:2847 kfree(vol_args);2848 return ret;2849}2850 2851static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,2852 void __user *arg)2853{2854 struct btrfs_ioctl_fs_info_args *fi_args;2855 struct btrfs_device *device;2856 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;2857 u64 flags_in;2858 int ret = 0;2859 2860 fi_args = memdup_user(arg, sizeof(*fi_args));2861 if (IS_ERR(fi_args))2862 return PTR_ERR(fi_args);2863 2864 flags_in = fi_args->flags;2865 memset(fi_args, 0, sizeof(*fi_args));2866 2867 rcu_read_lock();2868 fi_args->num_devices = fs_devices->num_devices;2869 2870 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {2871 if (device->devid > fi_args->max_id)2872 fi_args->max_id = device->devid;2873 }2874 rcu_read_unlock();2875 2876 memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));2877 fi_args->nodesize = fs_info->nodesize;2878 fi_args->sectorsize = fs_info->sectorsize;2879 fi_args->clone_alignment = fs_info->sectorsize;2880 2881 if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {2882 fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);2883 fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);2884 fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;2885 }2886 2887 if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {2888 fi_args->generation = btrfs_get_fs_generation(fs_info);2889 fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;2890 }2891 2892 if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {2893 memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,2894 sizeof(fi_args->metadata_uuid));2895 fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;2896 }2897 2898 if (copy_to_user(arg, fi_args, sizeof(*fi_args)))2899 ret = -EFAULT;2900 2901 kfree(fi_args);2902 return ret;2903}2904 2905static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,2906 void __user *arg)2907{2908 BTRFS_DEV_LOOKUP_ARGS(args);2909 struct btrfs_ioctl_dev_info_args *di_args;2910 struct btrfs_device *dev;2911 int ret = 0;2912 2913 di_args = memdup_user(arg, sizeof(*di_args));2914 if (IS_ERR(di_args))2915 return PTR_ERR(di_args);2916 2917 args.devid = di_args->devid;2918 if (!btrfs_is_empty_uuid(di_args->uuid))2919 args.uuid = di_args->uuid;2920 2921 rcu_read_lock();2922 dev = btrfs_find_device(fs_info->fs_devices, &args);2923 if (!dev) {2924 ret = -ENODEV;2925 goto out;2926 }2927 2928 di_args->devid = dev->devid;2929 di_args->bytes_used = btrfs_device_get_bytes_used(dev);2930 di_args->total_bytes = btrfs_device_get_total_bytes(dev);2931 memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));2932 memcpy(di_args->fsid, dev->fs_devices->fsid, BTRFS_UUID_SIZE);2933 if (dev->name)2934 strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path));2935 else2936 di_args->path[0] = '\0';2937 2938out:2939 rcu_read_unlock();2940 if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))2941 ret = -EFAULT;2942 2943 kfree(di_args);2944 return ret;2945}2946 2947static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)2948{2949 struct inode *inode = file_inode(file);2950 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);2951 struct btrfs_root *root = BTRFS_I(inode)->root;2952 struct btrfs_root *new_root;2953 struct btrfs_dir_item *di;2954 struct btrfs_trans_handle *trans;2955 struct btrfs_path *path = NULL;2956 struct btrfs_disk_key disk_key;2957 struct fscrypt_str name = FSTR_INIT("default", 7);2958 u64 objectid = 0;2959 u64 dir_id;2960 int ret;2961 2962 if (!capable(CAP_SYS_ADMIN))2963 return -EPERM;2964 2965 ret = mnt_want_write_file(file);2966 if (ret)2967 return ret;2968 2969 if (copy_from_user(&objectid, argp, sizeof(objectid))) {2970 ret = -EFAULT;2971 goto out;2972 }2973 2974 if (!objectid)2975 objectid = BTRFS_FS_TREE_OBJECTID;2976 2977 new_root = btrfs_get_fs_root(fs_info, objectid, true);2978 if (IS_ERR(new_root)) {2979 ret = PTR_ERR(new_root);2980 goto out;2981 }2982 if (!is_fstree(btrfs_root_id(new_root))) {2983 ret = -ENOENT;2984 goto out_free;2985 }2986 2987 path = btrfs_alloc_path();2988 if (!path) {2989 ret = -ENOMEM;2990 goto out_free;2991 }2992 2993 trans = btrfs_start_transaction(root, 1);2994 if (IS_ERR(trans)) {2995 ret = PTR_ERR(trans);2996 goto out_free;2997 }2998 2999 dir_id = btrfs_super_root_dir(fs_info->super_copy);3000 di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,3001 dir_id, &name, 1);3002 if (IS_ERR_OR_NULL(di)) {3003 btrfs_release_path(path);3004 btrfs_end_transaction(trans);3005 btrfs_err(fs_info,3006 "Umm, you don't have the default diritem, this isn't going to work");3007 ret = -ENOENT;3008 goto out_free;3009 }3010 3011 btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);3012 btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);3013 btrfs_mark_buffer_dirty(trans, path->nodes[0]);3014 btrfs_release_path(path);3015 3016 btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);3017 btrfs_end_transaction(trans);3018out_free:3019 btrfs_put_root(new_root);3020 btrfs_free_path(path);3021out:3022 mnt_drop_write_file(file);3023 return ret;3024}3025 3026static void get_block_group_info(struct list_head *groups_list,3027 struct btrfs_ioctl_space_info *space)3028{3029 struct btrfs_block_group *block_group;3030 3031 space->total_bytes = 0;3032 space->used_bytes = 0;3033 space->flags = 0;3034 list_for_each_entry(block_group, groups_list, list) {3035 space->flags = block_group->flags;3036 space->total_bytes += block_group->length;3037 space->used_bytes += block_group->used;3038 }3039}3040 3041static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,3042 void __user *arg)3043{3044 struct btrfs_ioctl_space_args space_args = { 0 };3045 struct btrfs_ioctl_space_info space;3046 struct btrfs_ioctl_space_info *dest;3047 struct btrfs_ioctl_space_info *dest_orig;3048 struct btrfs_ioctl_space_info __user *user_dest;3049 struct btrfs_space_info *info;3050 static const u64 types[] = {3051 BTRFS_BLOCK_GROUP_DATA,3052 BTRFS_BLOCK_GROUP_SYSTEM,3053 BTRFS_BLOCK_GROUP_METADATA,3054 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA3055 };3056 int num_types = 4;3057 int alloc_size;3058 int ret = 0;3059 u64 slot_count = 0;3060 int i, c;3061 3062 if (copy_from_user(&space_args,3063 (struct btrfs_ioctl_space_args __user *)arg,3064 sizeof(space_args)))3065 return -EFAULT;3066 3067 for (i = 0; i < num_types; i++) {3068 struct btrfs_space_info *tmp;3069 3070 info = NULL;3071 list_for_each_entry(tmp, &fs_info->space_info, list) {3072 if (tmp->flags == types[i]) {3073 info = tmp;3074 break;3075 }3076 }3077 3078 if (!info)3079 continue;3080 3081 down_read(&info->groups_sem);3082 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {3083 if (!list_empty(&info->block_groups[c]))3084 slot_count++;3085 }3086 up_read(&info->groups_sem);3087 }3088 3089 /*3090 * Global block reserve, exported as a space_info3091 */3092 slot_count++;3093 3094 /* space_slots == 0 means they are asking for a count */3095 if (space_args.space_slots == 0) {3096 space_args.total_spaces = slot_count;3097 goto out;3098 }3099 3100 slot_count = min_t(u64, space_args.space_slots, slot_count);3101 3102 alloc_size = sizeof(*dest) * slot_count;3103 3104 /* we generally have at most 6 or so space infos, one for each raid3105 * level. So, a whole page should be more than enough for everyone3106 */3107 if (alloc_size > PAGE_SIZE)3108 return -ENOMEM;3109 3110 space_args.total_spaces = 0;3111 dest = kmalloc(alloc_size, GFP_KERNEL);3112 if (!dest)3113 return -ENOMEM;3114 dest_orig = dest;3115 3116 /* now we have a buffer to copy into */3117 for (i = 0; i < num_types; i++) {3118 struct btrfs_space_info *tmp;3119 3120 if (!slot_count)3121 break;3122 3123 info = NULL;3124 list_for_each_entry(tmp, &fs_info->space_info, list) {3125 if (tmp->flags == types[i]) {3126 info = tmp;3127 break;3128 }3129 }3130 3131 if (!info)3132 continue;3133 down_read(&info->groups_sem);3134 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {3135 if (!list_empty(&info->block_groups[c])) {3136 get_block_group_info(&info->block_groups[c],3137 &space);3138 memcpy(dest, &space, sizeof(space));3139 dest++;3140 space_args.total_spaces++;3141 slot_count--;3142 }3143 if (!slot_count)3144 break;3145 }3146 up_read(&info->groups_sem);3147 }3148 3149 /*3150 * Add global block reserve3151 */3152 if (slot_count) {3153 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;3154 3155 spin_lock(&block_rsv->lock);3156 space.total_bytes = block_rsv->size;3157 space.used_bytes = block_rsv->size - block_rsv->reserved;3158 spin_unlock(&block_rsv->lock);3159 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;3160 memcpy(dest, &space, sizeof(space));3161 space_args.total_spaces++;3162 }3163 3164 user_dest = (struct btrfs_ioctl_space_info __user *)3165 (arg + sizeof(struct btrfs_ioctl_space_args));3166 3167 if (copy_to_user(user_dest, dest_orig, alloc_size))3168 ret = -EFAULT;3169 3170 kfree(dest_orig);3171out:3172 if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))3173 ret = -EFAULT;3174 3175 return ret;3176}3177 3178static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,3179 void __user *argp)3180{3181 struct btrfs_trans_handle *trans;3182 u64 transid;3183 3184 /*3185 * Start orphan cleanup here for the given root in case it hasn't been3186 * started already by other means. Errors are handled in the other3187 * functions during transaction commit.3188 */3189 btrfs_orphan_cleanup(root);3190 3191 trans = btrfs_attach_transaction_barrier(root);3192 if (IS_ERR(trans)) {3193 if (PTR_ERR(trans) != -ENOENT)3194 return PTR_ERR(trans);3195 3196 /* No running transaction, don't bother */3197 transid = btrfs_get_last_trans_committed(root->fs_info);3198 goto out;3199 }3200 transid = trans->transid;3201 btrfs_commit_transaction_async(trans);3202out:3203 if (argp)3204 if (copy_to_user(argp, &transid, sizeof(transid)))3205 return -EFAULT;3206 return 0;3207}3208 3209static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,3210 void __user *argp)3211{3212 /* By default wait for the current transaction. */3213 u64 transid = 0;3214 3215 if (argp)3216 if (copy_from_user(&transid, argp, sizeof(transid)))3217 return -EFAULT;3218 3219 return btrfs_wait_for_commit(fs_info, transid);3220}3221 3222static long btrfs_ioctl_scrub(struct file *file, void __user *arg)3223{3224 struct btrfs_fs_info *fs_info = inode_to_fs_info(file_inode(file));3225 struct btrfs_ioctl_scrub_args *sa;3226 int ret;3227 3228 if (!capable(CAP_SYS_ADMIN))3229 return -EPERM;3230 3231 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {3232 btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet");3233 return -EINVAL;3234 }3235 3236 sa = memdup_user(arg, sizeof(*sa));3237 if (IS_ERR(sa))3238 return PTR_ERR(sa);3239 3240 if (sa->flags & ~BTRFS_SCRUB_SUPPORTED_FLAGS) {3241 ret = -EOPNOTSUPP;3242 goto out;3243 }3244 3245 if (!(sa->flags & BTRFS_SCRUB_READONLY)) {3246 ret = mnt_want_write_file(file);3247 if (ret)3248 goto out;3249 }3250 3251 ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,3252 &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,3253 0);3254 3255 /*3256 * Copy scrub args to user space even if btrfs_scrub_dev() returned an3257 * error. This is important as it allows user space to know how much3258 * progress scrub has done. For example, if scrub is canceled we get3259 * -ECANCELED from btrfs_scrub_dev() and return that error back to user3260 * space. Later user space can inspect the progress from the structure3261 * btrfs_ioctl_scrub_args and resume scrub from where it left off3262 * previously (btrfs-progs does this).3263 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space3264 * then return -EFAULT to signal the structure was not copied or it may3265 * be corrupt and unreliable due to a partial copy.3266 */3267 if (copy_to_user(arg, sa, sizeof(*sa)))3268 ret = -EFAULT;3269 3270 if (!(sa->flags & BTRFS_SCRUB_READONLY))3271 mnt_drop_write_file(file);3272out:3273 kfree(sa);3274 return ret;3275}3276 3277static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)3278{3279 if (!capable(CAP_SYS_ADMIN))3280 return -EPERM;3281 3282 return btrfs_scrub_cancel(fs_info);3283}3284 3285static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,3286 void __user *arg)3287{3288 struct btrfs_ioctl_scrub_args *sa;3289 int ret;3290 3291 if (!capable(CAP_SYS_ADMIN))3292 return -EPERM;3293 3294 sa = memdup_user(arg, sizeof(*sa));3295 if (IS_ERR(sa))3296 return PTR_ERR(sa);3297 3298 ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);3299 3300 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))3301 ret = -EFAULT;3302 3303 kfree(sa);3304 return ret;3305}3306 3307static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,3308 void __user *arg)3309{3310 struct btrfs_ioctl_get_dev_stats *sa;3311 int ret;3312 3313 sa = memdup_user(arg, sizeof(*sa));3314 if (IS_ERR(sa))3315 return PTR_ERR(sa);3316 3317 if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {3318 kfree(sa);3319 return -EPERM;3320 }3321 3322 ret = btrfs_get_dev_stats(fs_info, sa);3323 3324 if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))3325 ret = -EFAULT;3326 3327 kfree(sa);3328 return ret;3329}3330 3331static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,3332 void __user *arg)3333{3334 struct btrfs_ioctl_dev_replace_args *p;3335 int ret;3336 3337 if (!capable(CAP_SYS_ADMIN))3338 return -EPERM;3339 3340 if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {3341 btrfs_err(fs_info, "device replace not supported on extent tree v2 yet");3342 return -EINVAL;3343 }3344 3345 p = memdup_user(arg, sizeof(*p));3346 if (IS_ERR(p))3347 return PTR_ERR(p);3348 3349 switch (p->cmd) {3350 case BTRFS_IOCTL_DEV_REPLACE_CMD_START:3351 if (sb_rdonly(fs_info->sb)) {3352 ret = -EROFS;3353 goto out;3354 }3355 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {3356 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;3357 } else {3358 ret = btrfs_dev_replace_by_ioctl(fs_info, p);3359 btrfs_exclop_finish(fs_info);3360 }3361 break;3362 case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:3363 btrfs_dev_replace_status(fs_info, p);3364 ret = 0;3365 break;3366 case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:3367 p->result = btrfs_dev_replace_cancel(fs_info);3368 ret = 0;3369 break;3370 default:3371 ret = -EINVAL;3372 break;3373 }3374 3375 if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))3376 ret = -EFAULT;3377out:3378 kfree(p);3379 return ret;3380}3381 3382static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)3383{3384 int ret = 0;3385 int i;3386 u64 rel_ptr;3387 int size;3388 struct btrfs_ioctl_ino_path_args *ipa = NULL;3389 struct inode_fs_paths *ipath = NULL;3390 struct btrfs_path *path;3391 3392 if (!capable(CAP_DAC_READ_SEARCH))3393 return -EPERM;3394 3395 path = btrfs_alloc_path();3396 if (!path) {3397 ret = -ENOMEM;3398 goto out;3399 }3400 3401 ipa = memdup_user(arg, sizeof(*ipa));3402 if (IS_ERR(ipa)) {3403 ret = PTR_ERR(ipa);3404 ipa = NULL;3405 goto out;3406 }3407 3408 size = min_t(u32, ipa->size, 4096);3409 ipath = init_ipath(size, root, path);3410 if (IS_ERR(ipath)) {3411 ret = PTR_ERR(ipath);3412 ipath = NULL;3413 goto out;3414 }3415 3416 ret = paths_from_inode(ipa->inum, ipath);3417 if (ret < 0)3418 goto out;3419 3420 for (i = 0; i < ipath->fspath->elem_cnt; ++i) {3421 rel_ptr = ipath->fspath->val[i] -3422 (u64)(unsigned long)ipath->fspath->val;3423 ipath->fspath->val[i] = rel_ptr;3424 }3425 3426 btrfs_free_path(path);3427 path = NULL;3428 ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,3429 ipath->fspath, size);3430 if (ret) {3431 ret = -EFAULT;3432 goto out;3433 }3434 3435out:3436 btrfs_free_path(path);3437 free_ipath(ipath);3438 kfree(ipa);3439 3440 return ret;3441}3442 3443static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,3444 void __user *arg, int version)3445{3446 int ret = 0;3447 int size;3448 struct btrfs_ioctl_logical_ino_args *loi;3449 struct btrfs_data_container *inodes = NULL;3450 struct btrfs_path *path = NULL;3451 bool ignore_offset;3452 3453 if (!capable(CAP_SYS_ADMIN))3454 return -EPERM;3455 3456 loi = memdup_user(arg, sizeof(*loi));3457 if (IS_ERR(loi))3458 return PTR_ERR(loi);3459 3460 if (version == 1) {3461 ignore_offset = false;3462 size = min_t(u32, loi->size, SZ_64K);3463 } else {3464 /* All reserved bits must be 0 for now */3465 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {3466 ret = -EINVAL;3467 goto out_loi;3468 }3469 /* Only accept flags we have defined so far */3470 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {3471 ret = -EINVAL;3472 goto out_loi;3473 }3474 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;3475 size = min_t(u32, loi->size, SZ_16M);3476 }3477 3478 inodes = init_data_container(size);3479 if (IS_ERR(inodes)) {3480 ret = PTR_ERR(inodes);3481 goto out_loi;3482 }3483 3484 path = btrfs_alloc_path();3485 if (!path) {3486 ret = -ENOMEM;3487 goto out;3488 }3489 ret = iterate_inodes_from_logical(loi->logical, fs_info, path,3490 inodes, ignore_offset);3491 btrfs_free_path(path);3492 if (ret == -EINVAL)3493 ret = -ENOENT;3494 if (ret < 0)3495 goto out;3496 3497 ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,3498 size);3499 if (ret)3500 ret = -EFAULT;3501 3502out:3503 kvfree(inodes);3504out_loi:3505 kfree(loi);3506 3507 return ret;3508}3509 3510void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,3511 struct btrfs_ioctl_balance_args *bargs)3512{3513 struct btrfs_balance_control *bctl = fs_info->balance_ctl;3514 3515 bargs->flags = bctl->flags;3516 3517 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))3518 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;3519 if (atomic_read(&fs_info->balance_pause_req))3520 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;3521 if (atomic_read(&fs_info->balance_cancel_req))3522 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;3523 3524 memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));3525 memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));3526 memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));3527 3528 spin_lock(&fs_info->balance_lock);3529 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));3530 spin_unlock(&fs_info->balance_lock);3531}3532 3533/*3534 * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as3535 * required.3536 *3537 * @fs_info: the filesystem3538 * @excl_acquired: ptr to boolean value which is set to false in case balance3539 * is being resumed3540 *3541 * Return 0 on success in which case both fs_info::balance is acquired as well3542 * as exclusive ops are blocked. In case of failure return an error code.3543 */3544static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired)3545{3546 int ret;3547 3548 /*3549 * Exclusive operation is locked. Three possibilities:3550 * (1) some other op is running3551 * (2) balance is running3552 * (3) balance is paused -- special case (think resume)3553 */3554 while (1) {3555 if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {3556 *excl_acquired = true;3557 mutex_lock(&fs_info->balance_mutex);3558 return 0;3559 }3560 3561 mutex_lock(&fs_info->balance_mutex);3562 if (fs_info->balance_ctl) {3563 /* This is either (2) or (3) */3564 if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {3565 /* This is (2) */3566 ret = -EINPROGRESS;3567 goto out_failure;3568 3569 } else {3570 mutex_unlock(&fs_info->balance_mutex);3571 /*3572 * Lock released to allow other waiters to3573 * continue, we'll reexamine the status again.3574 */3575 mutex_lock(&fs_info->balance_mutex);3576 3577 if (fs_info->balance_ctl &&3578 !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {3579 /* This is (3) */3580 *excl_acquired = false;3581 return 0;3582 }3583 }3584 } else {3585 /* This is (1) */3586 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;3587 goto out_failure;3588 }3589 3590 mutex_unlock(&fs_info->balance_mutex);3591 }3592 3593out_failure:3594 mutex_unlock(&fs_info->balance_mutex);3595 *excl_acquired = false;3596 return ret;3597}3598 3599static long btrfs_ioctl_balance(struct file *file, void __user *arg)3600{3601 struct btrfs_root *root = BTRFS_I(file_inode(file))->root;3602 struct btrfs_fs_info *fs_info = root->fs_info;3603 struct btrfs_ioctl_balance_args *bargs;3604 struct btrfs_balance_control *bctl;3605 bool need_unlock = true;3606 int ret;3607 3608 if (!capable(CAP_SYS_ADMIN))3609 return -EPERM;3610 3611 ret = mnt_want_write_file(file);3612 if (ret)3613 return ret;3614 3615 bargs = memdup_user(arg, sizeof(*bargs));3616 if (IS_ERR(bargs)) {3617 ret = PTR_ERR(bargs);3618 bargs = NULL;3619 goto out;3620 }3621 3622 ret = btrfs_try_lock_balance(fs_info, &need_unlock);3623 if (ret)3624 goto out;3625 3626 lockdep_assert_held(&fs_info->balance_mutex);3627 3628 if (bargs->flags & BTRFS_BALANCE_RESUME) {3629 if (!fs_info->balance_ctl) {3630 ret = -ENOTCONN;3631 goto out_unlock;3632 }3633 3634 bctl = fs_info->balance_ctl;3635 spin_lock(&fs_info->balance_lock);3636 bctl->flags |= BTRFS_BALANCE_RESUME;3637 spin_unlock(&fs_info->balance_lock);3638 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);3639 3640 goto do_balance;3641 }3642 3643 if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {3644 ret = -EINVAL;3645 goto out_unlock;3646 }3647 3648 if (fs_info->balance_ctl) {3649 ret = -EINPROGRESS;3650 goto out_unlock;3651 }3652 3653 bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);3654 if (!bctl) {3655 ret = -ENOMEM;3656 goto out_unlock;3657 }3658 3659 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));3660 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));3661 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));3662 3663 bctl->flags = bargs->flags;3664do_balance:3665 /*3666 * Ownership of bctl and exclusive operation goes to btrfs_balance.3667 * bctl is freed in reset_balance_state, or, if restriper was paused3668 * all the way until unmount, in free_fs_info. The flag should be3669 * cleared after reset_balance_state.3670 */3671 need_unlock = false;3672 3673 ret = btrfs_balance(fs_info, bctl, bargs);3674 bctl = NULL;3675 3676 if (ret == 0 || ret == -ECANCELED) {3677 if (copy_to_user(arg, bargs, sizeof(*bargs)))3678 ret = -EFAULT;3679 }3680 3681 kfree(bctl);3682out_unlock:3683 mutex_unlock(&fs_info->balance_mutex);3684 if (need_unlock)3685 btrfs_exclop_finish(fs_info);3686out:3687 mnt_drop_write_file(file);3688 kfree(bargs);3689 return ret;3690}3691 3692static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)3693{3694 if (!capable(CAP_SYS_ADMIN))3695 return -EPERM;3696 3697 switch (cmd) {3698 case BTRFS_BALANCE_CTL_PAUSE:3699 return btrfs_pause_balance(fs_info);3700 case BTRFS_BALANCE_CTL_CANCEL:3701 return btrfs_cancel_balance(fs_info);3702 }3703 3704 return -EINVAL;3705}3706 3707static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,3708 void __user *arg)3709{3710 struct btrfs_ioctl_balance_args *bargs;3711 int ret = 0;3712 3713 if (!capable(CAP_SYS_ADMIN))3714 return -EPERM;3715 3716 mutex_lock(&fs_info->balance_mutex);3717 if (!fs_info->balance_ctl) {3718 ret = -ENOTCONN;3719 goto out;3720 }3721 3722 bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);3723 if (!bargs) {3724 ret = -ENOMEM;3725 goto out;3726 }3727 3728 btrfs_update_ioctl_balance_args(fs_info, bargs);3729 3730 if (copy_to_user(arg, bargs, sizeof(*bargs)))3731 ret = -EFAULT;3732 3733 kfree(bargs);3734out:3735 mutex_unlock(&fs_info->balance_mutex);3736 return ret;3737}3738 3739static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)3740{3741 struct inode *inode = file_inode(file);3742 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);3743 struct btrfs_ioctl_quota_ctl_args *sa;3744 int ret;3745 3746 if (!capable(CAP_SYS_ADMIN))3747 return -EPERM;3748 3749 ret = mnt_want_write_file(file);3750 if (ret)3751 return ret;3752 3753 sa = memdup_user(arg, sizeof(*sa));3754 if (IS_ERR(sa)) {3755 ret = PTR_ERR(sa);3756 goto drop_write;3757 }3758 3759 switch (sa->cmd) {3760 case BTRFS_QUOTA_CTL_ENABLE:3761 case BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA:3762 down_write(&fs_info->subvol_sem);3763 ret = btrfs_quota_enable(fs_info, sa);3764 up_write(&fs_info->subvol_sem);3765 break;3766 case BTRFS_QUOTA_CTL_DISABLE:3767 /*3768 * Lock the cleaner mutex to prevent races with concurrent3769 * relocation, because relocation may be building backrefs for3770 * blocks of the quota root while we are deleting the root. This3771 * is like dropping fs roots of deleted snapshots/subvolumes, we3772 * need the same protection.3773 *3774 * This also prevents races between concurrent tasks trying to3775 * disable quotas, because we will unlock and relock3776 * qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes.3777 *3778 * We take this here because we have the dependency of3779 *3780 * inode_lock -> subvol_sem3781 *3782 * because of rename. With relocation we can prealloc extents,3783 * so that makes the dependency chain3784 *3785 * cleaner_mutex -> inode_lock -> subvol_sem3786 *3787 * so we must take the cleaner_mutex here before we take the3788 * subvol_sem. The deadlock can't actually happen, but this3789 * quiets lockdep.3790 */3791 mutex_lock(&fs_info->cleaner_mutex);3792 down_write(&fs_info->subvol_sem);3793 ret = btrfs_quota_disable(fs_info);3794 up_write(&fs_info->subvol_sem);3795 mutex_unlock(&fs_info->cleaner_mutex);3796 break;3797 default:3798 ret = -EINVAL;3799 break;3800 }3801 3802 kfree(sa);3803drop_write:3804 mnt_drop_write_file(file);3805 return ret;3806}3807 3808/*3809 * Quick check for ioctl handlers if quotas are enabled. Proper locking must be3810 * done before any operations.3811 */3812static bool qgroup_enabled(struct btrfs_fs_info *fs_info)3813{3814 bool ret = true;3815 3816 mutex_lock(&fs_info->qgroup_ioctl_lock);3817 if (!fs_info->quota_root)3818 ret = false;3819 mutex_unlock(&fs_info->qgroup_ioctl_lock);3820 3821 return ret;3822}3823 3824static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)3825{3826 struct inode *inode = file_inode(file);3827 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);3828 struct btrfs_root *root = BTRFS_I(inode)->root;3829 struct btrfs_ioctl_qgroup_assign_args *sa;3830 struct btrfs_qgroup_list *prealloc = NULL;3831 struct btrfs_trans_handle *trans;3832 int ret;3833 int err;3834 3835 if (!capable(CAP_SYS_ADMIN))3836 return -EPERM;3837 3838 if (!qgroup_enabled(root->fs_info))3839 return -ENOTCONN;3840 3841 ret = mnt_want_write_file(file);3842 if (ret)3843 return ret;3844 3845 sa = memdup_user(arg, sizeof(*sa));3846 if (IS_ERR(sa)) {3847 ret = PTR_ERR(sa);3848 goto drop_write;3849 }3850 3851 if (sa->assign) {3852 prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL);3853 if (!prealloc) {3854 ret = -ENOMEM;3855 goto drop_write;3856 }3857 }3858 3859 trans = btrfs_join_transaction(root);3860 if (IS_ERR(trans)) {3861 ret = PTR_ERR(trans);3862 goto out;3863 }3864 3865 /*3866 * Prealloc ownership is moved to the relation handler, there it's used3867 * or freed on error.3868 */3869 if (sa->assign) {3870 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst, prealloc);3871 prealloc = NULL;3872 } else {3873 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);3874 }3875 3876 /* update qgroup status and info */3877 mutex_lock(&fs_info->qgroup_ioctl_lock);3878 err = btrfs_run_qgroups(trans);3879 mutex_unlock(&fs_info->qgroup_ioctl_lock);3880 if (err < 0)3881 btrfs_warn(fs_info,3882 "qgroup status update failed after %s relation, marked as inconsistent",3883 sa->assign ? "adding" : "deleting");3884 err = btrfs_end_transaction(trans);3885 if (err && !ret)3886 ret = err;3887 3888out:3889 kfree(prealloc);3890 kfree(sa);3891drop_write:3892 mnt_drop_write_file(file);3893 return ret;3894}3895 3896static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)3897{3898 struct inode *inode = file_inode(file);3899 struct btrfs_root *root = BTRFS_I(inode)->root;3900 struct btrfs_ioctl_qgroup_create_args *sa;3901 struct btrfs_trans_handle *trans;3902 int ret;3903 int err;3904 3905 if (!capable(CAP_SYS_ADMIN))3906 return -EPERM;3907 3908 if (!qgroup_enabled(root->fs_info))3909 return -ENOTCONN;3910 3911 ret = mnt_want_write_file(file);3912 if (ret)3913 return ret;3914 3915 sa = memdup_user(arg, sizeof(*sa));3916 if (IS_ERR(sa)) {3917 ret = PTR_ERR(sa);3918 goto drop_write;3919 }3920 3921 if (!sa->qgroupid) {3922 ret = -EINVAL;3923 goto out;3924 }3925 3926 if (sa->create && is_fstree(sa->qgroupid)) {3927 ret = -EINVAL;3928 goto out;3929 }3930 3931 trans = btrfs_join_transaction(root);3932 if (IS_ERR(trans)) {3933 ret = PTR_ERR(trans);3934 goto out;3935 }3936 3937 if (sa->create) {3938 ret = btrfs_create_qgroup(trans, sa->qgroupid);3939 } else {3940 ret = btrfs_remove_qgroup(trans, sa->qgroupid);3941 }3942 3943 err = btrfs_end_transaction(trans);3944 if (err && !ret)3945 ret = err;3946 3947out:3948 kfree(sa);3949drop_write:3950 mnt_drop_write_file(file);3951 return ret;3952}3953 3954static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)3955{3956 struct inode *inode = file_inode(file);3957 struct btrfs_root *root = BTRFS_I(inode)->root;3958 struct btrfs_ioctl_qgroup_limit_args *sa;3959 struct btrfs_trans_handle *trans;3960 int ret;3961 int err;3962 u64 qgroupid;3963 3964 if (!capable(CAP_SYS_ADMIN))3965 return -EPERM;3966 3967 if (!qgroup_enabled(root->fs_info))3968 return -ENOTCONN;3969 3970 ret = mnt_want_write_file(file);3971 if (ret)3972 return ret;3973 3974 sa = memdup_user(arg, sizeof(*sa));3975 if (IS_ERR(sa)) {3976 ret = PTR_ERR(sa);3977 goto drop_write;3978 }3979 3980 trans = btrfs_join_transaction(root);3981 if (IS_ERR(trans)) {3982 ret = PTR_ERR(trans);3983 goto out;3984 }3985 3986 qgroupid = sa->qgroupid;3987 if (!qgroupid) {3988 /* take the current subvol as qgroup */3989 qgroupid = btrfs_root_id(root);3990 }3991 3992 ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);3993 3994 err = btrfs_end_transaction(trans);3995 if (err && !ret)3996 ret = err;3997 3998out:3999 kfree(sa);4000drop_write:4001 mnt_drop_write_file(file);4002 return ret;4003}4004 4005static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)4006{4007 struct inode *inode = file_inode(file);4008 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);4009 struct btrfs_ioctl_quota_rescan_args *qsa;4010 int ret;4011 4012 if (!capable(CAP_SYS_ADMIN))4013 return -EPERM;4014 4015 if (!qgroup_enabled(fs_info))4016 return -ENOTCONN;4017 4018 ret = mnt_want_write_file(file);4019 if (ret)4020 return ret;4021 4022 qsa = memdup_user(arg, sizeof(*qsa));4023 if (IS_ERR(qsa)) {4024 ret = PTR_ERR(qsa);4025 goto drop_write;4026 }4027 4028 if (qsa->flags) {4029 ret = -EINVAL;4030 goto out;4031 }4032 4033 ret = btrfs_qgroup_rescan(fs_info);4034 4035out:4036 kfree(qsa);4037drop_write:4038 mnt_drop_write_file(file);4039 return ret;4040}4041 4042static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,4043 void __user *arg)4044{4045 struct btrfs_ioctl_quota_rescan_args qsa = {0};4046 4047 if (!capable(CAP_SYS_ADMIN))4048 return -EPERM;4049 4050 if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {4051 qsa.flags = 1;4052 qsa.progress = fs_info->qgroup_rescan_progress.objectid;4053 }4054 4055 if (copy_to_user(arg, &qsa, sizeof(qsa)))4056 return -EFAULT;4057 4058 return 0;4059}4060 4061static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,4062 void __user *arg)4063{4064 if (!capable(CAP_SYS_ADMIN))4065 return -EPERM;4066 4067 return btrfs_qgroup_wait_for_completion(fs_info, true);4068}4069 4070static long _btrfs_ioctl_set_received_subvol(struct file *file,4071 struct mnt_idmap *idmap,4072 struct btrfs_ioctl_received_subvol_args *sa)4073{4074 struct inode *inode = file_inode(file);4075 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);4076 struct btrfs_root *root = BTRFS_I(inode)->root;4077 struct btrfs_root_item *root_item = &root->root_item;4078 struct btrfs_trans_handle *trans;4079 struct timespec64 ct = current_time(inode);4080 int ret = 0;4081 int received_uuid_changed;4082 4083 if (!inode_owner_or_capable(idmap, inode))4084 return -EPERM;4085 4086 ret = mnt_want_write_file(file);4087 if (ret < 0)4088 return ret;4089 4090 down_write(&fs_info->subvol_sem);4091 4092 if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {4093 ret = -EINVAL;4094 goto out;4095 }4096 4097 if (btrfs_root_readonly(root)) {4098 ret = -EROFS;4099 goto out;4100 }4101 4102 /*4103 * 1 - root item4104 * 2 - uuid items (received uuid + subvol uuid)4105 */4106 trans = btrfs_start_transaction(root, 3);4107 if (IS_ERR(trans)) {4108 ret = PTR_ERR(trans);4109 trans = NULL;4110 goto out;4111 }4112 4113 sa->rtransid = trans->transid;4114 sa->rtime.sec = ct.tv_sec;4115 sa->rtime.nsec = ct.tv_nsec;4116 4117 received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,4118 BTRFS_UUID_SIZE);4119 if (received_uuid_changed &&4120 !btrfs_is_empty_uuid(root_item->received_uuid)) {4121 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,4122 BTRFS_UUID_KEY_RECEIVED_SUBVOL,4123 btrfs_root_id(root));4124 if (ret && ret != -ENOENT) {4125 btrfs_abort_transaction(trans, ret);4126 btrfs_end_transaction(trans);4127 goto out;4128 }4129 }4130 memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);4131 btrfs_set_root_stransid(root_item, sa->stransid);4132 btrfs_set_root_rtransid(root_item, sa->rtransid);4133 btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);4134 btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);4135 btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);4136 btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);4137 4138 ret = btrfs_update_root(trans, fs_info->tree_root,4139 &root->root_key, &root->root_item);4140 if (ret < 0) {4141 btrfs_end_transaction(trans);4142 goto out;4143 }4144 if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {4145 ret = btrfs_uuid_tree_add(trans, sa->uuid,4146 BTRFS_UUID_KEY_RECEIVED_SUBVOL,4147 btrfs_root_id(root));4148 if (ret < 0 && ret != -EEXIST) {4149 btrfs_abort_transaction(trans, ret);4150 btrfs_end_transaction(trans);4151 goto out;4152 }4153 }4154 ret = btrfs_commit_transaction(trans);4155out:4156 up_write(&fs_info->subvol_sem);4157 mnt_drop_write_file(file);4158 return ret;4159}4160 4161#ifdef CONFIG_64BIT4162static long btrfs_ioctl_set_received_subvol_32(struct file *file,4163 void __user *arg)4164{4165 struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;4166 struct btrfs_ioctl_received_subvol_args *args64 = NULL;4167 int ret = 0;4168 4169 args32 = memdup_user(arg, sizeof(*args32));4170 if (IS_ERR(args32))4171 return PTR_ERR(args32);4172 4173 args64 = kmalloc(sizeof(*args64), GFP_KERNEL);4174 if (!args64) {4175 ret = -ENOMEM;4176 goto out;4177 }4178 4179 memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);4180 args64->stransid = args32->stransid;4181 args64->rtransid = args32->rtransid;4182 args64->stime.sec = args32->stime.sec;4183 args64->stime.nsec = args32->stime.nsec;4184 args64->rtime.sec = args32->rtime.sec;4185 args64->rtime.nsec = args32->rtime.nsec;4186 args64->flags = args32->flags;4187 4188 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), args64);4189 if (ret)4190 goto out;4191 4192 memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);4193 args32->stransid = args64->stransid;4194 args32->rtransid = args64->rtransid;4195 args32->stime.sec = args64->stime.sec;4196 args32->stime.nsec = args64->stime.nsec;4197 args32->rtime.sec = args64->rtime.sec;4198 args32->rtime.nsec = args64->rtime.nsec;4199 args32->flags = args64->flags;4200 4201 ret = copy_to_user(arg, args32, sizeof(*args32));4202 if (ret)4203 ret = -EFAULT;4204 4205out:4206 kfree(args32);4207 kfree(args64);4208 return ret;4209}4210#endif4211 4212static long btrfs_ioctl_set_received_subvol(struct file *file,4213 void __user *arg)4214{4215 struct btrfs_ioctl_received_subvol_args *sa = NULL;4216 int ret = 0;4217 4218 sa = memdup_user(arg, sizeof(*sa));4219 if (IS_ERR(sa))4220 return PTR_ERR(sa);4221 4222 ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_idmap(file), sa);4223 4224 if (ret)4225 goto out;4226 4227 ret = copy_to_user(arg, sa, sizeof(*sa));4228 if (ret)4229 ret = -EFAULT;4230 4231out:4232 kfree(sa);4233 return ret;4234}4235 4236static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,4237 void __user *arg)4238{4239 size_t len;4240 int ret;4241 char label[BTRFS_LABEL_SIZE];4242 4243 spin_lock(&fs_info->super_lock);4244 memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);4245 spin_unlock(&fs_info->super_lock);4246 4247 len = strnlen(label, BTRFS_LABEL_SIZE);4248 4249 if (len == BTRFS_LABEL_SIZE) {4250 btrfs_warn(fs_info,4251 "label is too long, return the first %zu bytes",4252 --len);4253 }4254 4255 ret = copy_to_user(arg, label, len);4256 4257 return ret ? -EFAULT : 0;4258}4259 4260static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)4261{4262 struct inode *inode = file_inode(file);4263 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);4264 struct btrfs_root *root = BTRFS_I(inode)->root;4265 struct btrfs_super_block *super_block = fs_info->super_copy;4266 struct btrfs_trans_handle *trans;4267 char label[BTRFS_LABEL_SIZE];4268 int ret;4269 4270 if (!capable(CAP_SYS_ADMIN))4271 return -EPERM;4272 4273 if (copy_from_user(label, arg, sizeof(label)))4274 return -EFAULT;4275 4276 if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {4277 btrfs_err(fs_info,4278 "unable to set label with more than %d bytes",4279 BTRFS_LABEL_SIZE - 1);4280 return -EINVAL;4281 }4282 4283 ret = mnt_want_write_file(file);4284 if (ret)4285 return ret;4286 4287 trans = btrfs_start_transaction(root, 0);4288 if (IS_ERR(trans)) {4289 ret = PTR_ERR(trans);4290 goto out_unlock;4291 }4292 4293 spin_lock(&fs_info->super_lock);4294 strcpy(super_block->label, label);4295 spin_unlock(&fs_info->super_lock);4296 ret = btrfs_commit_transaction(trans);4297 4298out_unlock:4299 mnt_drop_write_file(file);4300 return ret;4301}4302 4303#define INIT_FEATURE_FLAGS(suffix) \4304 { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \4305 .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \4306 .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }4307 4308int btrfs_ioctl_get_supported_features(void __user *arg)4309{4310 static const struct btrfs_ioctl_feature_flags features[3] = {4311 INIT_FEATURE_FLAGS(SUPP),4312 INIT_FEATURE_FLAGS(SAFE_SET),4313 INIT_FEATURE_FLAGS(SAFE_CLEAR)4314 };4315 4316 if (copy_to_user(arg, &features, sizeof(features)))4317 return -EFAULT;4318 4319 return 0;4320}4321 4322static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,4323 void __user *arg)4324{4325 struct btrfs_super_block *super_block = fs_info->super_copy;4326 struct btrfs_ioctl_feature_flags features;4327 4328 features.compat_flags = btrfs_super_compat_flags(super_block);4329 features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);4330 features.incompat_flags = btrfs_super_incompat_flags(super_block);4331 4332 if (copy_to_user(arg, &features, sizeof(features)))4333 return -EFAULT;4334 4335 return 0;4336}4337 4338static int check_feature_bits(struct btrfs_fs_info *fs_info,4339 enum btrfs_feature_set set,4340 u64 change_mask, u64 flags, u64 supported_flags,4341 u64 safe_set, u64 safe_clear)4342{4343 const char *type = btrfs_feature_set_name(set);4344 char *names;4345 u64 disallowed, unsupported;4346 u64 set_mask = flags & change_mask;4347 u64 clear_mask = ~flags & change_mask;4348 4349 unsupported = set_mask & ~supported_flags;4350 if (unsupported) {4351 names = btrfs_printable_features(set, unsupported);4352 if (names) {4353 btrfs_warn(fs_info,4354 "this kernel does not support the %s feature bit%s",4355 names, strchr(names, ',') ? "s" : "");4356 kfree(names);4357 } else4358 btrfs_warn(fs_info,4359 "this kernel does not support %s bits 0x%llx",4360 type, unsupported);4361 return -EOPNOTSUPP;4362 }4363 4364 disallowed = set_mask & ~safe_set;4365 if (disallowed) {4366 names = btrfs_printable_features(set, disallowed);4367 if (names) {4368 btrfs_warn(fs_info,4369 "can't set the %s feature bit%s while mounted",4370 names, strchr(names, ',') ? "s" : "");4371 kfree(names);4372 } else4373 btrfs_warn(fs_info,4374 "can't set %s bits 0x%llx while mounted",4375 type, disallowed);4376 return -EPERM;4377 }4378 4379 disallowed = clear_mask & ~safe_clear;4380 if (disallowed) {4381 names = btrfs_printable_features(set, disallowed);4382 if (names) {4383 btrfs_warn(fs_info,4384 "can't clear the %s feature bit%s while mounted",4385 names, strchr(names, ',') ? "s" : "");4386 kfree(names);4387 } else4388 btrfs_warn(fs_info,4389 "can't clear %s bits 0x%llx while mounted",4390 type, disallowed);4391 return -EPERM;4392 }4393 4394 return 0;4395}4396 4397#define check_feature(fs_info, change_mask, flags, mask_base) \4398check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags, \4399 BTRFS_FEATURE_ ## mask_base ## _SUPP, \4400 BTRFS_FEATURE_ ## mask_base ## _SAFE_SET, \4401 BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)4402 4403static int btrfs_ioctl_set_features(struct file *file, void __user *arg)4404{4405 struct inode *inode = file_inode(file);4406 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);4407 struct btrfs_root *root = BTRFS_I(inode)->root;4408 struct btrfs_super_block *super_block = fs_info->super_copy;4409 struct btrfs_ioctl_feature_flags flags[2];4410 struct btrfs_trans_handle *trans;4411 u64 newflags;4412 int ret;4413 4414 if (!capable(CAP_SYS_ADMIN))4415 return -EPERM;4416 4417 if (copy_from_user(flags, arg, sizeof(flags)))4418 return -EFAULT;4419 4420 /* Nothing to do */4421 if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&4422 !flags[0].incompat_flags)4423 return 0;4424 4425 ret = check_feature(fs_info, flags[0].compat_flags,4426 flags[1].compat_flags, COMPAT);4427 if (ret)4428 return ret;4429 4430 ret = check_feature(fs_info, flags[0].compat_ro_flags,4431 flags[1].compat_ro_flags, COMPAT_RO);4432 if (ret)4433 return ret;4434 4435 ret = check_feature(fs_info, flags[0].incompat_flags,4436 flags[1].incompat_flags, INCOMPAT);4437 if (ret)4438 return ret;4439 4440 ret = mnt_want_write_file(file);4441 if (ret)4442 return ret;4443 4444 trans = btrfs_start_transaction(root, 0);4445 if (IS_ERR(trans)) {4446 ret = PTR_ERR(trans);4447 goto out_drop_write;4448 }4449 4450 spin_lock(&fs_info->super_lock);4451 newflags = btrfs_super_compat_flags(super_block);4452 newflags |= flags[0].compat_flags & flags[1].compat_flags;4453 newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);4454 btrfs_set_super_compat_flags(super_block, newflags);4455 4456 newflags = btrfs_super_compat_ro_flags(super_block);4457 newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;4458 newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);4459 btrfs_set_super_compat_ro_flags(super_block, newflags);4460 4461 newflags = btrfs_super_incompat_flags(super_block);4462 newflags |= flags[0].incompat_flags & flags[1].incompat_flags;4463 newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);4464 btrfs_set_super_incompat_flags(super_block, newflags);4465 spin_unlock(&fs_info->super_lock);4466 4467 ret = btrfs_commit_transaction(trans);4468out_drop_write:4469 mnt_drop_write_file(file);4470 4471 return ret;4472}4473 4474static int _btrfs_ioctl_send(struct btrfs_inode *inode, void __user *argp, bool compat)4475{4476 struct btrfs_ioctl_send_args *arg;4477 int ret;4478 4479 if (compat) {4480#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)4481 struct btrfs_ioctl_send_args_32 args32 = { 0 };4482 4483 ret = copy_from_user(&args32, argp, sizeof(args32));4484 if (ret)4485 return -EFAULT;4486 arg = kzalloc(sizeof(*arg), GFP_KERNEL);4487 if (!arg)4488 return -ENOMEM;4489 arg->send_fd = args32.send_fd;4490 arg->clone_sources_count = args32.clone_sources_count;4491 arg->clone_sources = compat_ptr(args32.clone_sources);4492 arg->parent_root = args32.parent_root;4493 arg->flags = args32.flags;4494 arg->version = args32.version;4495 memcpy(arg->reserved, args32.reserved,4496 sizeof(args32.reserved));4497#else4498 return -ENOTTY;4499#endif4500 } else {4501 arg = memdup_user(argp, sizeof(*arg));4502 if (IS_ERR(arg))4503 return PTR_ERR(arg);4504 }4505 ret = btrfs_ioctl_send(inode, arg);4506 kfree(arg);4507 return ret;4508}4509 4510static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,4511 bool compat)4512{4513 struct btrfs_ioctl_encoded_io_args args = { 0 };4514 size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args,4515 flags);4516 size_t copy_end;4517 struct iovec iovstack[UIO_FASTIOV];4518 struct iovec *iov = iovstack;4519 struct iov_iter iter;4520 loff_t pos;4521 struct kiocb kiocb;4522 ssize_t ret;4523 4524 if (!capable(CAP_SYS_ADMIN)) {4525 ret = -EPERM;4526 goto out_acct;4527 }4528 4529 if (compat) {4530#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)4531 struct btrfs_ioctl_encoded_io_args_32 args32;4532 4533 copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32,4534 flags);4535 if (copy_from_user(&args32, argp, copy_end)) {4536 ret = -EFAULT;4537 goto out_acct;4538 }4539 args.iov = compat_ptr(args32.iov);4540 args.iovcnt = args32.iovcnt;4541 args.offset = args32.offset;4542 args.flags = args32.flags;4543#else4544 return -ENOTTY;4545#endif4546 } else {4547 copy_end = copy_end_kernel;4548 if (copy_from_user(&args, argp, copy_end)) {4549 ret = -EFAULT;4550 goto out_acct;4551 }4552 }4553 if (args.flags != 0) {4554 ret = -EINVAL;4555 goto out_acct;4556 }4557 4558 ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),4559 &iov, &iter);4560 if (ret < 0)4561 goto out_acct;4562 4563 if (iov_iter_count(&iter) == 0) {4564 ret = 0;4565 goto out_iov;4566 }4567 pos = args.offset;4568 ret = rw_verify_area(READ, file, &pos, args.len);4569 if (ret < 0)4570 goto out_iov;4571 4572 init_sync_kiocb(&kiocb, file);4573 kiocb.ki_pos = pos;4574 4575 ret = btrfs_encoded_read(&kiocb, &iter, &args);4576 if (ret >= 0) {4577 fsnotify_access(file);4578 if (copy_to_user(argp + copy_end,4579 (char *)&args + copy_end_kernel,4580 sizeof(args) - copy_end_kernel))4581 ret = -EFAULT;4582 }4583 4584out_iov:4585 kfree(iov);4586out_acct:4587 if (ret > 0)4588 add_rchar(current, ret);4589 inc_syscr(current);4590 return ret;4591}4592 4593static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat)4594{4595 struct btrfs_ioctl_encoded_io_args args;4596 struct iovec iovstack[UIO_FASTIOV];4597 struct iovec *iov = iovstack;4598 struct iov_iter iter;4599 loff_t pos;4600 struct kiocb kiocb;4601 ssize_t ret;4602 4603 if (!capable(CAP_SYS_ADMIN)) {4604 ret = -EPERM;4605 goto out_acct;4606 }4607 4608 if (!(file->f_mode & FMODE_WRITE)) {4609 ret = -EBADF;4610 goto out_acct;4611 }4612 4613 if (compat) {4614#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)4615 struct btrfs_ioctl_encoded_io_args_32 args32;4616 4617 if (copy_from_user(&args32, argp, sizeof(args32))) {4618 ret = -EFAULT;4619 goto out_acct;4620 }4621 args.iov = compat_ptr(args32.iov);4622 args.iovcnt = args32.iovcnt;4623 args.offset = args32.offset;4624 args.flags = args32.flags;4625 args.len = args32.len;4626 args.unencoded_len = args32.unencoded_len;4627 args.unencoded_offset = args32.unencoded_offset;4628 args.compression = args32.compression;4629 args.encryption = args32.encryption;4630 memcpy(args.reserved, args32.reserved, sizeof(args.reserved));4631#else4632 return -ENOTTY;4633#endif4634 } else {4635 if (copy_from_user(&args, argp, sizeof(args))) {4636 ret = -EFAULT;4637 goto out_acct;4638 }4639 }4640 4641 ret = -EINVAL;4642 if (args.flags != 0)4643 goto out_acct;4644 if (memchr_inv(args.reserved, 0, sizeof(args.reserved)))4645 goto out_acct;4646 if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE &&4647 args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE)4648 goto out_acct;4649 if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES ||4650 args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES)4651 goto out_acct;4652 if (args.unencoded_offset > args.unencoded_len)4653 goto out_acct;4654 if (args.len > args.unencoded_len - args.unencoded_offset)4655 goto out_acct;4656 4657 ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),4658 &iov, &iter);4659 if (ret < 0)4660 goto out_acct;4661 4662 if (iov_iter_count(&iter) == 0) {4663 ret = 0;4664 goto out_iov;4665 }4666 pos = args.offset;4667 ret = rw_verify_area(WRITE, file, &pos, args.len);4668 if (ret < 0)4669 goto out_iov;4670 4671 init_sync_kiocb(&kiocb, file);4672 ret = kiocb_set_rw_flags(&kiocb, 0, WRITE);4673 if (ret)4674 goto out_iov;4675 kiocb.ki_pos = pos;4676 4677 file_start_write(file);4678 4679 ret = btrfs_do_write_iter(&kiocb, &iter, &args);4680 if (ret > 0)4681 fsnotify_modify(file);4682 4683 file_end_write(file);4684out_iov:4685 kfree(iov);4686out_acct:4687 if (ret > 0)4688 add_wchar(current, ret);4689 inc_syscw(current);4690 return ret;4691}4692 4693long btrfs_ioctl(struct file *file, unsigned int4694 cmd, unsigned long arg)4695{4696 struct inode *inode = file_inode(file);4697 struct btrfs_fs_info *fs_info = inode_to_fs_info(inode);4698 struct btrfs_root *root = BTRFS_I(inode)->root;4699 void __user *argp = (void __user *)arg;4700 4701 switch (cmd) {4702 case FS_IOC_GETVERSION:4703 return btrfs_ioctl_getversion(inode, argp);4704 case FS_IOC_GETFSLABEL:4705 return btrfs_ioctl_get_fslabel(fs_info, argp);4706 case FS_IOC_SETFSLABEL:4707 return btrfs_ioctl_set_fslabel(file, argp);4708 case FITRIM:4709 return btrfs_ioctl_fitrim(fs_info, argp);4710 case BTRFS_IOC_SNAP_CREATE:4711 return btrfs_ioctl_snap_create(file, argp, 0);4712 case BTRFS_IOC_SNAP_CREATE_V2:4713 return btrfs_ioctl_snap_create_v2(file, argp, 0);4714 case BTRFS_IOC_SUBVOL_CREATE:4715 return btrfs_ioctl_snap_create(file, argp, 1);4716 case BTRFS_IOC_SUBVOL_CREATE_V2:4717 return btrfs_ioctl_snap_create_v2(file, argp, 1);4718 case BTRFS_IOC_SNAP_DESTROY:4719 return btrfs_ioctl_snap_destroy(file, argp, false);4720 case BTRFS_IOC_SNAP_DESTROY_V2:4721 return btrfs_ioctl_snap_destroy(file, argp, true);4722 case BTRFS_IOC_SUBVOL_GETFLAGS:4723 return btrfs_ioctl_subvol_getflags(inode, argp);4724 case BTRFS_IOC_SUBVOL_SETFLAGS:4725 return btrfs_ioctl_subvol_setflags(file, argp);4726 case BTRFS_IOC_DEFAULT_SUBVOL:4727 return btrfs_ioctl_default_subvol(file, argp);4728 case BTRFS_IOC_DEFRAG:4729 return btrfs_ioctl_defrag(file, NULL);4730 case BTRFS_IOC_DEFRAG_RANGE:4731 return btrfs_ioctl_defrag(file, argp);4732 case BTRFS_IOC_RESIZE:4733 return btrfs_ioctl_resize(file, argp);4734 case BTRFS_IOC_ADD_DEV:4735 return btrfs_ioctl_add_dev(fs_info, argp);4736 case BTRFS_IOC_RM_DEV:4737 return btrfs_ioctl_rm_dev(file, argp);4738 case BTRFS_IOC_RM_DEV_V2:4739 return btrfs_ioctl_rm_dev_v2(file, argp);4740 case BTRFS_IOC_FS_INFO:4741 return btrfs_ioctl_fs_info(fs_info, argp);4742 case BTRFS_IOC_DEV_INFO:4743 return btrfs_ioctl_dev_info(fs_info, argp);4744 case BTRFS_IOC_TREE_SEARCH:4745 return btrfs_ioctl_tree_search(inode, argp);4746 case BTRFS_IOC_TREE_SEARCH_V2:4747 return btrfs_ioctl_tree_search_v2(inode, argp);4748 case BTRFS_IOC_INO_LOOKUP:4749 return btrfs_ioctl_ino_lookup(root, argp);4750 case BTRFS_IOC_INO_PATHS:4751 return btrfs_ioctl_ino_to_path(root, argp);4752 case BTRFS_IOC_LOGICAL_INO:4753 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);4754 case BTRFS_IOC_LOGICAL_INO_V2:4755 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);4756 case BTRFS_IOC_SPACE_INFO:4757 return btrfs_ioctl_space_info(fs_info, argp);4758 case BTRFS_IOC_SYNC: {4759 int ret;4760 4761 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);4762 if (ret)4763 return ret;4764 ret = btrfs_sync_fs(inode->i_sb, 1);4765 /*4766 * There may be work for the cleaner kthread to do (subvolume4767 * deletion, delayed iputs, defrag inodes, etc), so wake it up.4768 */4769 wake_up_process(fs_info->cleaner_kthread);4770 return ret;4771 }4772 case BTRFS_IOC_START_SYNC:4773 return btrfs_ioctl_start_sync(root, argp);4774 case BTRFS_IOC_WAIT_SYNC:4775 return btrfs_ioctl_wait_sync(fs_info, argp);4776 case BTRFS_IOC_SCRUB:4777 return btrfs_ioctl_scrub(file, argp);4778 case BTRFS_IOC_SCRUB_CANCEL:4779 return btrfs_ioctl_scrub_cancel(fs_info);4780 case BTRFS_IOC_SCRUB_PROGRESS:4781 return btrfs_ioctl_scrub_progress(fs_info, argp);4782 case BTRFS_IOC_BALANCE_V2:4783 return btrfs_ioctl_balance(file, argp);4784 case BTRFS_IOC_BALANCE_CTL:4785 return btrfs_ioctl_balance_ctl(fs_info, arg);4786 case BTRFS_IOC_BALANCE_PROGRESS:4787 return btrfs_ioctl_balance_progress(fs_info, argp);4788 case BTRFS_IOC_SET_RECEIVED_SUBVOL:4789 return btrfs_ioctl_set_received_subvol(file, argp);4790#ifdef CONFIG_64BIT4791 case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:4792 return btrfs_ioctl_set_received_subvol_32(file, argp);4793#endif4794 case BTRFS_IOC_SEND:4795 return _btrfs_ioctl_send(BTRFS_I(inode), argp, false);4796#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)4797 case BTRFS_IOC_SEND_32:4798 return _btrfs_ioctl_send(BTRFS_I(inode), argp, true);4799#endif4800 case BTRFS_IOC_GET_DEV_STATS:4801 return btrfs_ioctl_get_dev_stats(fs_info, argp);4802 case BTRFS_IOC_QUOTA_CTL:4803 return btrfs_ioctl_quota_ctl(file, argp);4804 case BTRFS_IOC_QGROUP_ASSIGN:4805 return btrfs_ioctl_qgroup_assign(file, argp);4806 case BTRFS_IOC_QGROUP_CREATE:4807 return btrfs_ioctl_qgroup_create(file, argp);4808 case BTRFS_IOC_QGROUP_LIMIT:4809 return btrfs_ioctl_qgroup_limit(file, argp);4810 case BTRFS_IOC_QUOTA_RESCAN:4811 return btrfs_ioctl_quota_rescan(file, argp);4812 case BTRFS_IOC_QUOTA_RESCAN_STATUS:4813 return btrfs_ioctl_quota_rescan_status(fs_info, argp);4814 case BTRFS_IOC_QUOTA_RESCAN_WAIT:4815 return btrfs_ioctl_quota_rescan_wait(fs_info, argp);4816 case BTRFS_IOC_DEV_REPLACE:4817 return btrfs_ioctl_dev_replace(fs_info, argp);4818 case BTRFS_IOC_GET_SUPPORTED_FEATURES:4819 return btrfs_ioctl_get_supported_features(argp);4820 case BTRFS_IOC_GET_FEATURES:4821 return btrfs_ioctl_get_features(fs_info, argp);4822 case BTRFS_IOC_SET_FEATURES:4823 return btrfs_ioctl_set_features(file, argp);4824 case BTRFS_IOC_GET_SUBVOL_INFO:4825 return btrfs_ioctl_get_subvol_info(inode, argp);4826 case BTRFS_IOC_GET_SUBVOL_ROOTREF:4827 return btrfs_ioctl_get_subvol_rootref(root, argp);4828 case BTRFS_IOC_INO_LOOKUP_USER:4829 return btrfs_ioctl_ino_lookup_user(file, argp);4830 case FS_IOC_ENABLE_VERITY:4831 return fsverity_ioctl_enable(file, (const void __user *)argp);4832 case FS_IOC_MEASURE_VERITY:4833 return fsverity_ioctl_measure(file, argp);4834 case BTRFS_IOC_ENCODED_READ:4835 return btrfs_ioctl_encoded_read(file, argp, false);4836 case BTRFS_IOC_ENCODED_WRITE:4837 return btrfs_ioctl_encoded_write(file, argp, false);4838#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)4839 case BTRFS_IOC_ENCODED_READ_32:4840 return btrfs_ioctl_encoded_read(file, argp, true);4841 case BTRFS_IOC_ENCODED_WRITE_32:4842 return btrfs_ioctl_encoded_write(file, argp, true);4843#endif4844 }4845 4846 return -ENOTTY;4847}4848 4849#ifdef CONFIG_COMPAT4850long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)4851{4852 /*4853 * These all access 32-bit values anyway so no further4854 * handling is necessary.4855 */4856 switch (cmd) {4857 case FS_IOC32_GETVERSION:4858 cmd = FS_IOC_GETVERSION;4859 break;4860 }4861 4862 return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));4863}4864#endif4865