From ff023aac31198e88507d626825379b28ea481d4d Mon Sep 17 00:00:00 2001 From: Stefan Behrens Date: Tue, 6 Nov 2012 11:43:11 +0100 Subject: Btrfs: add code to scrub to copy read data to another disk The device replace procedure makes use of the scrub code. The scrub code is the most efficient code to read the allocated data of a disk, i.e. it reads sequentially in order to avoid disk head movements, it skips unallocated blocks, it uses read ahead mechanisms, and it contains all the code to detect and repair defects. This commit adds code to scrub to allow the scrub code to copy read data to another disk. One goal is to be able to perform as fast as possible. Therefore the write requests are collected until huge bios are built, and the write process is decoupled from the read process with some kind of flow control, of course, in order to limit the allocated memory. The best performance on spinning disks could by reached when the head movements are avoided as much as possible. Therefore a single worker is used to interface the read process with the write process. The regular scrub operation works as fast as before, it is not negatively influenced and actually it is more or less unchanged. Signed-off-by: Stefan Behrens Signed-off-by: Chris Mason --- fs/btrfs/dev-replace.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 fs/btrfs/dev-replace.h (limited to 'fs/btrfs/dev-replace.h') diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h new file mode 100644 index 00000000000..1fb5c89037e --- /dev/null +++ b/fs/btrfs/dev-replace.h @@ -0,0 +1,26 @@ +/* + * Copyright (C) STRATO AG 2012. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#if !defined(__BTRFS_DEV_REPLACE__) +#define __BTRFS_DEV_REPLACE__ + +static inline void btrfs_dev_replace_stats_inc(atomic64_t *stat_value) +{ + atomic64_inc(stat_value); +} +#endif -- cgit v1.2.3-70-g09d2 From e93c89c1aaaaaec3487c4c18dd02360371790722 Mon Sep 17 00:00:00 2001 From: Stefan Behrens Date: Mon, 5 Nov 2012 17:33:06 +0100 Subject: Btrfs: add new sources for device replace code This adds a new file to the sources together with the header file and the changes to ioctl.h and ctree.h that are required by the new C source file. Additionally, 4 new functions are added to volume.c that deal with device creation and destruction. Signed-off-by: Stefan Behrens Signed-off-by: Chris Mason --- fs/btrfs/Makefile | 2 +- fs/btrfs/ctree.h | 2 + fs/btrfs/dev-replace.c | 856 +++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/dev-replace.h | 18 ++ fs/btrfs/ioctl.h | 45 +++ fs/btrfs/volumes.c | 139 ++++++++ fs/btrfs/volumes.h | 8 + 7 files changed, 1069 insertions(+), 1 deletion(-) create mode 100644 fs/btrfs/dev-replace.c (limited to 'fs/btrfs/dev-replace.h') diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index d7fcdba141a..7df3e0f0ee5 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -8,7 +8,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \ export.o tree-log.o free-space-cache.o zlib.o lzo.o \ compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \ - reada.o backref.o ulist.o qgroup.o send.o + reada.o backref.o ulist.o qgroup.o send.o dev-replace.o btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index ded7caa0d30..45e7f752b64 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -142,6 +142,8 @@ struct btrfs_ordered_sum; #define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2 +#define BTRFS_DEV_REPLACE_DEVID 0 + /* * the max metadata block size. This limit is somewhat artificial, * but the memmove costs go through the roof for larger blocks. diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c new file mode 100644 index 00000000000..66dbc8dbddf --- /dev/null +++ b/fs/btrfs/dev-replace.c @@ -0,0 +1,856 @@ +/* + * Copyright (C) STRATO AG 2012. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "compat.h" +#include "ctree.h" +#include "extent_map.h" +#include "disk-io.h" +#include "transaction.h" +#include "print-tree.h" +#include "volumes.h" +#include "async-thread.h" +#include "check-integrity.h" +#include "rcu-string.h" +#include "dev-replace.h" + +static u64 btrfs_get_seconds_since_1970(void); +static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, + int scrub_ret); +static void btrfs_dev_replace_update_device_in_mapping_tree( + struct btrfs_fs_info *fs_info, + struct btrfs_device *srcdev, + struct btrfs_device *tgtdev); +static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid, + char *srcdev_name, + struct btrfs_device **device); +static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info); +static int btrfs_dev_replace_kthread(void *data); +static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info); + + +int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info) +{ + struct btrfs_key key; + struct btrfs_root *dev_root = fs_info->dev_root; + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + struct extent_buffer *eb; + int slot; + int ret = 0; + struct btrfs_path *path = NULL; + int item_size; + struct btrfs_dev_replace_item *ptr; + u64 src_devid; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + key.objectid = 0; + key.type = BTRFS_DEV_REPLACE_KEY; + key.offset = 0; + ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); + if (ret) { +no_valid_dev_replace_entry_found: + ret = 0; + dev_replace->replace_state = + BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED; + dev_replace->cont_reading_from_srcdev_mode = + BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS; + dev_replace->replace_state = 0; + dev_replace->time_started = 0; + dev_replace->time_stopped = 0; + atomic64_set(&dev_replace->num_write_errors, 0); + atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); + dev_replace->cursor_left = 0; + dev_replace->committed_cursor_left = 0; + dev_replace->cursor_left_last_write_of_item = 0; + dev_replace->cursor_right = 0; + dev_replace->srcdev = NULL; + dev_replace->tgtdev = NULL; + dev_replace->is_valid = 0; + dev_replace->item_needs_writeback = 0; + goto out; + } + slot = path->slots[0]; + eb = path->nodes[0]; + item_size = btrfs_item_size_nr(eb, slot); + ptr = btrfs_item_ptr(eb, slot, struct btrfs_dev_replace_item); + + if (item_size != sizeof(struct btrfs_dev_replace_item)) { + pr_warn("btrfs: dev_replace entry found has unexpected size, ignore entry\n"); + goto no_valid_dev_replace_entry_found; + } + + src_devid = btrfs_dev_replace_src_devid(eb, ptr); + dev_replace->cont_reading_from_srcdev_mode = + btrfs_dev_replace_cont_reading_from_srcdev_mode(eb, ptr); + dev_replace->replace_state = btrfs_dev_replace_replace_state(eb, ptr); + dev_replace->time_started = btrfs_dev_replace_time_started(eb, ptr); + dev_replace->time_stopped = + btrfs_dev_replace_time_stopped(eb, ptr); + atomic64_set(&dev_replace->num_write_errors, + btrfs_dev_replace_num_write_errors(eb, ptr)); + atomic64_set(&dev_replace->num_uncorrectable_read_errors, + btrfs_dev_replace_num_uncorrectable_read_errors(eb, ptr)); + dev_replace->cursor_left = btrfs_dev_replace_cursor_left(eb, ptr); + dev_replace->committed_cursor_left = dev_replace->cursor_left; + dev_replace->cursor_left_last_write_of_item = dev_replace->cursor_left; + dev_replace->cursor_right = btrfs_dev_replace_cursor_right(eb, ptr); + dev_replace->is_valid = 1; + + dev_replace->item_needs_writeback = 0; + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + dev_replace->srcdev = NULL; + dev_replace->tgtdev = NULL; + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + dev_replace->srcdev = btrfs_find_device(fs_info, src_devid, + NULL, NULL); + dev_replace->tgtdev = btrfs_find_device(fs_info, + BTRFS_DEV_REPLACE_DEVID, + NULL, NULL); + /* + * allow 'btrfs dev replace_cancel' if src/tgt device is + * missing + */ + if (!dev_replace->srcdev && + !btrfs_test_opt(dev_root, DEGRADED)) { + ret = -EIO; + pr_warn("btrfs: cannot mount because device replace operation is ongoing and\n" "srcdev (devid %llu) is missing, need to run 'btrfs dev scan'?\n", + (unsigned long long)src_devid); + } + if (!dev_replace->tgtdev && + !btrfs_test_opt(dev_root, DEGRADED)) { + ret = -EIO; + pr_warn("btrfs: cannot mount because device replace operation is ongoing and\n" "tgtdev (devid %llu) is missing, need to run btrfs dev scan?\n", + (unsigned long long)BTRFS_DEV_REPLACE_DEVID); + } + if (dev_replace->tgtdev) { + if (dev_replace->srcdev) { + dev_replace->tgtdev->total_bytes = + dev_replace->srcdev->total_bytes; + dev_replace->tgtdev->disk_total_bytes = + dev_replace->srcdev->disk_total_bytes; + dev_replace->tgtdev->bytes_used = + dev_replace->srcdev->bytes_used; + } + dev_replace->tgtdev->is_tgtdev_for_dev_replace = 1; + btrfs_init_dev_replace_tgtdev_for_resume(fs_info, + dev_replace->tgtdev); + } + break; + } + +out: + if (path) + btrfs_free_path(path); + return ret; +} + +/* + * called from commit_transaction. Writes changed device replace state to + * disk. + */ +int btrfs_run_dev_replace(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info) +{ + int ret; + struct btrfs_root *dev_root = fs_info->dev_root; + struct btrfs_path *path; + struct btrfs_key key; + struct extent_buffer *eb; + struct btrfs_dev_replace_item *ptr; + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + + btrfs_dev_replace_lock(dev_replace); + if (!dev_replace->is_valid || + !dev_replace->item_needs_writeback) { + btrfs_dev_replace_unlock(dev_replace); + return 0; + } + btrfs_dev_replace_unlock(dev_replace); + + key.objectid = 0; + key.type = BTRFS_DEV_REPLACE_KEY; + key.offset = 0; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); + if (ret < 0) { + pr_warn("btrfs: error %d while searching for dev_replace item!\n", + ret); + goto out; + } + + if (ret == 0 && + btrfs_item_size_nr(path->nodes[0], path->slots[0]) < sizeof(*ptr)) { + /* + * need to delete old one and insert a new one. + * Since no attempt is made to recover any old state, if the + * dev_replace state is 'running', the data on the target + * drive is lost. + * It would be possible to recover the state: just make sure + * that the beginning of the item is never changed and always + * contains all the essential information. Then read this + * minimal set of information and use it as a base for the + * new state. + */ + ret = btrfs_del_item(trans, dev_root, path); + if (ret != 0) { + pr_warn("btrfs: delete too small dev_replace item failed %d!\n", + ret); + goto out; + } + ret = 1; + } + + if (ret == 1) { + /* need to insert a new item */ + btrfs_release_path(path); + ret = btrfs_insert_empty_item(trans, dev_root, path, + &key, sizeof(*ptr)); + if (ret < 0) { + pr_warn("btrfs: insert dev_replace item failed %d!\n", + ret); + goto out; + } + } + + eb = path->nodes[0]; + ptr = btrfs_item_ptr(eb, path->slots[0], + struct btrfs_dev_replace_item); + + btrfs_dev_replace_lock(dev_replace); + if (dev_replace->srcdev) + btrfs_set_dev_replace_src_devid(eb, ptr, + dev_replace->srcdev->devid); + else + btrfs_set_dev_replace_src_devid(eb, ptr, (u64)-1); + btrfs_set_dev_replace_cont_reading_from_srcdev_mode(eb, ptr, + dev_replace->cont_reading_from_srcdev_mode); + btrfs_set_dev_replace_replace_state(eb, ptr, + dev_replace->replace_state); + btrfs_set_dev_replace_time_started(eb, ptr, dev_replace->time_started); + btrfs_set_dev_replace_time_stopped(eb, ptr, dev_replace->time_stopped); + btrfs_set_dev_replace_num_write_errors(eb, ptr, + atomic64_read(&dev_replace->num_write_errors)); + btrfs_set_dev_replace_num_uncorrectable_read_errors(eb, ptr, + atomic64_read(&dev_replace->num_uncorrectable_read_errors)); + dev_replace->cursor_left_last_write_of_item = + dev_replace->cursor_left; + btrfs_set_dev_replace_cursor_left(eb, ptr, + dev_replace->cursor_left_last_write_of_item); + btrfs_set_dev_replace_cursor_right(eb, ptr, + dev_replace->cursor_right); + dev_replace->item_needs_writeback = 0; + btrfs_dev_replace_unlock(dev_replace); + + btrfs_mark_buffer_dirty(eb); + +out: + btrfs_free_path(path); + + return ret; +} + +void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + + dev_replace->committed_cursor_left = + dev_replace->cursor_left_last_write_of_item; +} + +static u64 btrfs_get_seconds_since_1970(void) +{ + struct timespec t = CURRENT_TIME_SEC; + + return t.tv_sec; +} + +int btrfs_dev_replace_start(struct btrfs_root *root, + struct btrfs_ioctl_dev_replace_args *args) +{ + struct btrfs_trans_handle *trans; + struct btrfs_fs_info *fs_info = root->fs_info; + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + int ret; + struct btrfs_device *tgt_device = NULL; + struct btrfs_device *src_device = NULL; + + switch (args->start.cont_reading_from_srcdev_mode) { + case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS: + case BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID: + break; + default: + return -EINVAL; + } + + if ((args->start.srcdevid == 0 && args->start.srcdev_name[0] == '\0') || + args->start.tgtdev_name[0] == '\0') + return -EINVAL; + + mutex_lock(&fs_info->volume_mutex); + ret = btrfs_init_dev_replace_tgtdev(root, args->start.tgtdev_name, + &tgt_device); + if (ret) { + pr_err("btrfs: target device %s is invalid!\n", + args->start.tgtdev_name); + mutex_unlock(&fs_info->volume_mutex); + return -EINVAL; + } + + ret = btrfs_dev_replace_find_srcdev(root, args->start.srcdevid, + args->start.srcdev_name, + &src_device); + mutex_unlock(&fs_info->volume_mutex); + if (ret) { + ret = -EINVAL; + goto leave_no_lock; + } + + if (tgt_device->total_bytes < src_device->total_bytes) { + pr_err("btrfs: target device is smaller than source device!\n"); + ret = -EINVAL; + goto leave_no_lock; + } + + btrfs_dev_replace_lock(dev_replace); + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; + goto leave; + } + + dev_replace->cont_reading_from_srcdev_mode = + args->start.cont_reading_from_srcdev_mode; + WARN_ON(!src_device); + dev_replace->srcdev = src_device; + WARN_ON(!tgt_device); + dev_replace->tgtdev = tgt_device; + + printk_in_rcu(KERN_INFO + "btrfs: dev_replace from %s (devid %llu) to %s) started\n", + src_device->missing ? "" : + rcu_str_deref(src_device->name), + src_device->devid, + rcu_str_deref(tgt_device->name)); + + tgt_device->total_bytes = src_device->total_bytes; + tgt_device->disk_total_bytes = src_device->disk_total_bytes; + tgt_device->bytes_used = src_device->bytes_used; + + /* + * from now on, the writes to the srcdev are all duplicated to + * go to the tgtdev as well (refer to btrfs_map_block()). + */ + dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; + dev_replace->time_started = btrfs_get_seconds_since_1970(); + dev_replace->cursor_left = 0; + dev_replace->committed_cursor_left = 0; + dev_replace->cursor_left_last_write_of_item = 0; + dev_replace->cursor_right = 0; + dev_replace->is_valid = 1; + dev_replace->item_needs_writeback = 1; + args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; + btrfs_dev_replace_unlock(dev_replace); + + btrfs_wait_ordered_extents(root, 0); + + /* force writing the updated state information to disk */ + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + btrfs_dev_replace_lock(dev_replace); + goto leave; + } + + ret = btrfs_commit_transaction(trans, root); + WARN_ON(ret); + + /* the disk copy procedure reuses the scrub code */ + ret = btrfs_scrub_dev(fs_info, src_device->devid, 0, + src_device->total_bytes, + &dev_replace->scrub_progress, 0, 1); + + ret = btrfs_dev_replace_finishing(root->fs_info, ret); + WARN_ON(ret); + + return 0; + +leave: + dev_replace->srcdev = NULL; + dev_replace->tgtdev = NULL; + btrfs_dev_replace_unlock(dev_replace); +leave_no_lock: + if (tgt_device) + btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); + return ret; +} + +static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info, + int scrub_ret) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + struct btrfs_device *tgt_device; + struct btrfs_device *src_device; + struct btrfs_root *root = fs_info->tree_root; + u8 uuid_tmp[BTRFS_UUID_SIZE]; + struct btrfs_trans_handle *trans; + int ret = 0; + + /* don't allow cancel or unmount to disturb the finishing procedure */ + mutex_lock(&dev_replace->lock_finishing_cancel_unmount); + + btrfs_dev_replace_lock(dev_replace); + /* was the operation canceled, or is it finished? */ + if (dev_replace->replace_state != + BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { + btrfs_dev_replace_unlock(dev_replace); + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + return 0; + } + + tgt_device = dev_replace->tgtdev; + src_device = dev_replace->srcdev; + btrfs_dev_replace_unlock(dev_replace); + + /* replace old device with new one in mapping tree */ + if (!scrub_ret) + btrfs_dev_replace_update_device_in_mapping_tree(fs_info, + src_device, + tgt_device); + + /* + * flush all outstanding I/O and inode extent mappings before the + * copy operation is declared as being finished + */ + btrfs_start_delalloc_inodes(root, 0); + btrfs_wait_ordered_extents(root, 0); + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + return PTR_ERR(trans); + } + ret = btrfs_commit_transaction(trans, root); + WARN_ON(ret); + + /* keep away write_all_supers() during the finishing procedure */ + mutex_lock(&root->fs_info->fs_devices->device_list_mutex); + btrfs_dev_replace_lock(dev_replace); + dev_replace->replace_state = + scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED + : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; + dev_replace->tgtdev = NULL; + dev_replace->srcdev = NULL; + dev_replace->time_stopped = btrfs_get_seconds_since_1970(); + dev_replace->item_needs_writeback = 1; + + if (scrub_ret) { + printk_in_rcu(KERN_ERR + "btrfs: btrfs_scrub_dev(%s, %llu, %s) failed %d\n", + src_device->missing ? "" : + rcu_str_deref(src_device->name), + src_device->devid, + rcu_str_deref(tgt_device->name), scrub_ret); + btrfs_dev_replace_unlock(dev_replace); + mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); + if (tgt_device) + btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + + return 0; + } + + printk_in_rcu(KERN_INFO + "btrfs: dev_replace from %s (devid %llu) to %s) finished\n", + src_device->missing ? "" : + rcu_str_deref(src_device->name), + src_device->devid, + rcu_str_deref(tgt_device->name)); + tgt_device->is_tgtdev_for_dev_replace = 0; + tgt_device->devid = src_device->devid; + src_device->devid = BTRFS_DEV_REPLACE_DEVID; + tgt_device->bytes_used = src_device->bytes_used; + memcpy(uuid_tmp, tgt_device->uuid, sizeof(uuid_tmp)); + memcpy(tgt_device->uuid, src_device->uuid, sizeof(tgt_device->uuid)); + memcpy(src_device->uuid, uuid_tmp, sizeof(src_device->uuid)); + tgt_device->total_bytes = src_device->total_bytes; + tgt_device->disk_total_bytes = src_device->disk_total_bytes; + tgt_device->bytes_used = src_device->bytes_used; + if (fs_info->sb->s_bdev == src_device->bdev) + fs_info->sb->s_bdev = tgt_device->bdev; + if (fs_info->fs_devices->latest_bdev == src_device->bdev) + fs_info->fs_devices->latest_bdev = tgt_device->bdev; + list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); + + btrfs_rm_dev_replace_srcdev(fs_info, src_device); + if (src_device->bdev) { + /* zero out the old super */ + btrfs_scratch_superblock(src_device); + } + /* + * this is again a consistent state where no dev_replace procedure + * is running, the target device is part of the filesystem, the + * source device is not part of the filesystem anymore and its 1st + * superblock is scratched out so that it is no longer marked to + * belong to this filesystem. + */ + btrfs_dev_replace_unlock(dev_replace); + mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); + + /* write back the superblocks */ + trans = btrfs_start_transaction(root, 0); + if (!IS_ERR(trans)) + btrfs_commit_transaction(trans, root); + + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + + return 0; +} + +static void btrfs_dev_replace_update_device_in_mapping_tree( + struct btrfs_fs_info *fs_info, + struct btrfs_device *srcdev, + struct btrfs_device *tgtdev) +{ + struct extent_map_tree *em_tree = &fs_info->mapping_tree.map_tree; + struct extent_map *em; + struct map_lookup *map; + u64 start = 0; + int i; + + write_lock(&em_tree->lock); + do { + em = lookup_extent_mapping(em_tree, start, (u64)-1); + if (!em) + break; + map = (struct map_lookup *)em->bdev; + for (i = 0; i < map->num_stripes; i++) + if (srcdev == map->stripes[i].dev) + map->stripes[i].dev = tgtdev; + start = em->start + em->len; + free_extent_map(em); + } while (start); + write_unlock(&em_tree->lock); +} + +static int btrfs_dev_replace_find_srcdev(struct btrfs_root *root, u64 srcdevid, + char *srcdev_name, + struct btrfs_device **device) +{ + int ret; + + if (srcdevid) { + ret = 0; + *device = btrfs_find_device(root->fs_info, srcdevid, NULL, + NULL); + if (!*device) + ret = -ENOENT; + } else { + ret = btrfs_find_device_missing_or_by_path(root, srcdev_name, + device); + } + return ret; +} + +void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + + btrfs_dev_replace_lock(dev_replace); + /* even if !dev_replace_is_valid, the values are good enough for + * the replace_status ioctl */ + args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; + args->status.replace_state = dev_replace->replace_state; + args->status.time_started = dev_replace->time_started; + args->status.time_stopped = dev_replace->time_stopped; + args->status.num_write_errors = + atomic64_read(&dev_replace->num_write_errors); + args->status.num_uncorrectable_read_errors = + atomic64_read(&dev_replace->num_uncorrectable_read_errors); + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + args->status.progress_1000 = 0; + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + args->status.progress_1000 = 1000; + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + args->status.progress_1000 = div64_u64(dev_replace->cursor_left, + div64_u64(dev_replace->srcdev->total_bytes, 1000)); + break; + } + btrfs_dev_replace_unlock(dev_replace); +} + +int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args) +{ + args->result = __btrfs_dev_replace_cancel(fs_info); + return 0; +} + +static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + struct btrfs_device *tgt_device = NULL; + struct btrfs_trans_handle *trans; + struct btrfs_root *root = fs_info->tree_root; + u64 result; + int ret; + + mutex_lock(&dev_replace->lock_finishing_cancel_unmount); + btrfs_dev_replace_lock(dev_replace); + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; + btrfs_dev_replace_unlock(dev_replace); + goto leave; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR; + tgt_device = dev_replace->tgtdev; + dev_replace->tgtdev = NULL; + dev_replace->srcdev = NULL; + break; + } + dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED; + dev_replace->time_stopped = btrfs_get_seconds_since_1970(); + dev_replace->item_needs_writeback = 1; + btrfs_dev_replace_unlock(dev_replace); + btrfs_scrub_cancel(fs_info); + + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + return PTR_ERR(trans); + } + ret = btrfs_commit_transaction(trans, root); + WARN_ON(ret); + if (tgt_device) + btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device); + +leave: + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + return result; +} + +void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + + mutex_lock(&dev_replace->lock_finishing_cancel_unmount); + btrfs_dev_replace_lock(dev_replace); + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + dev_replace->replace_state = + BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; + dev_replace->time_stopped = btrfs_get_seconds_since_1970(); + dev_replace->item_needs_writeback = 1; + pr_info("btrfs: suspending dev_replace for unmount\n"); + break; + } + + btrfs_dev_replace_unlock(dev_replace); + mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); +} + +/* resume dev_replace procedure that was interrupted by unmount */ +int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info) +{ + struct task_struct *task; + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + + btrfs_dev_replace_lock(dev_replace); + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + btrfs_dev_replace_unlock(dev_replace); + return 0; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + break; + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + dev_replace->replace_state = + BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED; + break; + } + if (!dev_replace->tgtdev || !dev_replace->tgtdev->bdev) { + pr_info("btrfs: cannot continue dev_replace, tgtdev is missing\n" + "btrfs: you may cancel the operation after 'mount -o degraded'\n"); + btrfs_dev_replace_unlock(dev_replace); + return 0; + } + btrfs_dev_replace_unlock(dev_replace); + + WARN_ON(atomic_xchg( + &fs_info->mutually_exclusive_operation_running, 1)); + task = kthread_run(btrfs_dev_replace_kthread, fs_info, "btrfs-devrepl"); + return PTR_RET(task); +} + +static int btrfs_dev_replace_kthread(void *data) +{ + struct btrfs_fs_info *fs_info = data; + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + struct btrfs_ioctl_dev_replace_args *status_args; + u64 progress; + + status_args = kzalloc(sizeof(*status_args), GFP_NOFS); + if (status_args) { + btrfs_dev_replace_status(fs_info, status_args); + progress = status_args->status.progress_1000; + kfree(status_args); + do_div(progress, 10); + printk_in_rcu(KERN_INFO + "btrfs: continuing dev_replace from %s (devid %llu) to %s @%u%%\n", + dev_replace->srcdev->missing ? "" : + rcu_str_deref(dev_replace->srcdev->name), + dev_replace->srcdev->devid, + dev_replace->tgtdev ? + rcu_str_deref(dev_replace->tgtdev->name) : + "", + (unsigned int)progress); + } + btrfs_dev_replace_continue_on_mount(fs_info); + atomic_set(&fs_info->mutually_exclusive_operation_running, 0); + + return 0; +} + +static int btrfs_dev_replace_continue_on_mount(struct btrfs_fs_info *fs_info) +{ + struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; + int ret; + + ret = btrfs_scrub_dev(fs_info, dev_replace->srcdev->devid, + dev_replace->committed_cursor_left, + dev_replace->srcdev->total_bytes, + &dev_replace->scrub_progress, 0, 1); + ret = btrfs_dev_replace_finishing(fs_info, ret); + WARN_ON(ret); + return 0; +} + +int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) +{ + if (!dev_replace->is_valid) + return 0; + + switch (dev_replace->replace_state) { + case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED: + return 0; + case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: + case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: + /* + * return true even if tgtdev is missing (this is + * something that can happen if the dev_replace + * procedure is suspended by an umount and then + * the tgtdev is missing (or "btrfs dev scan") was + * not called and the the filesystem is remounted + * in degraded state. This does not stop the + * dev_replace procedure. It needs to be canceled + * manually if the cancelation is wanted. + */ + break; + } + return 1; +} + +void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace) +{ + /* the beginning is just an optimization for the typical case */ + if (atomic_read(&dev_replace->nesting_level) == 0) { +acquire_lock: + /* this is not a nested case where the same thread + * is trying to acqurire the same lock twice */ + mutex_lock(&dev_replace->lock); + mutex_lock(&dev_replace->lock_management_lock); + dev_replace->lock_owner = current->pid; + atomic_inc(&dev_replace->nesting_level); + mutex_unlock(&dev_replace->lock_management_lock); + return; + } + + mutex_lock(&dev_replace->lock_management_lock); + if (atomic_read(&dev_replace->nesting_level) > 0 && + dev_replace->lock_owner == current->pid) { + WARN_ON(!mutex_is_locked(&dev_replace->lock)); + atomic_inc(&dev_replace->nesting_level); + mutex_unlock(&dev_replace->lock_management_lock); + return; + } + + mutex_unlock(&dev_replace->lock_management_lock); + goto acquire_lock; +} + +void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace) +{ + WARN_ON(!mutex_is_locked(&dev_replace->lock)); + mutex_lock(&dev_replace->lock_management_lock); + WARN_ON(atomic_read(&dev_replace->nesting_level) < 1); + WARN_ON(dev_replace->lock_owner != current->pid); + atomic_dec(&dev_replace->nesting_level); + if (atomic_read(&dev_replace->nesting_level) == 0) { + dev_replace->lock_owner = 0; + mutex_unlock(&dev_replace->lock_management_lock); + mutex_unlock(&dev_replace->lock); + } else { + mutex_unlock(&dev_replace->lock_management_lock); + } +} diff --git a/fs/btrfs/dev-replace.h b/fs/btrfs/dev-replace.h index 1fb5c89037e..20035cbbf02 100644 --- a/fs/btrfs/dev-replace.h +++ b/fs/btrfs/dev-replace.h @@ -19,6 +19,24 @@ #if !defined(__BTRFS_DEV_REPLACE__) #define __BTRFS_DEV_REPLACE__ +struct btrfs_ioctl_dev_replace_args; + +int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info); +int btrfs_run_dev_replace(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info); +void btrfs_after_dev_replace_commit(struct btrfs_fs_info *fs_info); +int btrfs_dev_replace_start(struct btrfs_root *root, + struct btrfs_ioctl_dev_replace_args *args); +void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args); +int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info, + struct btrfs_ioctl_dev_replace_args *args); +void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info); +int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info); +int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace); +void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace); +void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace); + static inline void btrfs_dev_replace_stats_inc(atomic64_t *stat_value) { atomic64_inc(stat_value); diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 731e2875ab9..62006ba0271 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -123,6 +123,48 @@ struct btrfs_ioctl_scrub_args { __u64 unused[(1024-32-sizeof(struct btrfs_scrub_progress))/8]; }; +#define BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_ALWAYS 0 +#define BTRFS_IOCTL_DEV_REPLACE_CONT_READING_FROM_SRCDEV_MODE_AVOID 1 +struct btrfs_ioctl_dev_replace_start_params { + __u64 srcdevid; /* in, if 0, use srcdev_name instead */ + __u8 srcdev_name[BTRFS_PATH_NAME_MAX + 1]; /* in */ + __u8 tgtdev_name[BTRFS_PATH_NAME_MAX + 1]; /* in */ + __u64 cont_reading_from_srcdev_mode; /* in, see #define + * above */ +}; + +#define BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED 0 +#define BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED 1 +#define BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED 2 +#define BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED 3 +#define BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED 4 +struct btrfs_ioctl_dev_replace_status_params { + __u64 replace_state; /* out, see #define above */ + __u64 progress_1000; /* out, 0 <= x <= 1000 */ + __u64 time_started; /* out, seconds since 1-Jan-1970 */ + __u64 time_stopped; /* out, seconds since 1-Jan-1970 */ + __u64 num_write_errors; /* out */ + __u64 num_uncorrectable_read_errors; /* out */ +}; + +#define BTRFS_IOCTL_DEV_REPLACE_CMD_START 0 +#define BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS 1 +#define BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL 2 +#define BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR 0 +#define BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED 1 +#define BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED 2 +struct btrfs_ioctl_dev_replace_args { + __u64 cmd; /* in */ + __u64 result; /* out */ + + union { + struct btrfs_ioctl_dev_replace_start_params start; + struct btrfs_ioctl_dev_replace_status_params status; + }; /* in/out */ + + __u64 spare[64]; +}; + #define BTRFS_DEVICE_PATH_NAME_MAX 1024 struct btrfs_ioctl_dev_info_args { __u64 devid; /* in/out */ @@ -453,4 +495,7 @@ struct btrfs_ioctl_send_args { struct btrfs_ioctl_qgroup_limit_args) #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ struct btrfs_ioctl_get_dev_stats) +#define BTRFS_IOC_DEV_REPLACE _IOWR(BTRFS_IOCTL_MAGIC, 53, \ + struct btrfs_ioctl_dev_replace_args) + #endif diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 415862885b6..5777e6a9aab 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1537,6 +1537,53 @@ error_undo: goto error_brelse; } +void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, + struct btrfs_device *srcdev) +{ + WARN_ON(!mutex_is_locked(&fs_info->fs_devices->device_list_mutex)); + list_del_rcu(&srcdev->dev_list); + list_del_rcu(&srcdev->dev_alloc_list); + fs_info->fs_devices->num_devices--; + if (srcdev->missing) { + fs_info->fs_devices->missing_devices--; + fs_info->fs_devices->rw_devices++; + } + if (srcdev->can_discard) + fs_info->fs_devices->num_can_discard--; + if (srcdev->bdev) + fs_info->fs_devices->open_devices--; + + call_rcu(&srcdev->rcu, free_device); +} + +void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, + struct btrfs_device *tgtdev) +{ + struct btrfs_device *next_device; + + WARN_ON(!tgtdev); + mutex_lock(&fs_info->fs_devices->device_list_mutex); + if (tgtdev->bdev) { + btrfs_scratch_superblock(tgtdev); + fs_info->fs_devices->open_devices--; + } + fs_info->fs_devices->num_devices--; + if (tgtdev->can_discard) + fs_info->fs_devices->num_can_discard++; + + next_device = list_entry(fs_info->fs_devices->devices.next, + struct btrfs_device, dev_list); + if (tgtdev->bdev == fs_info->sb->s_bdev) + fs_info->sb->s_bdev = next_device->bdev; + if (tgtdev->bdev == fs_info->fs_devices->latest_bdev) + fs_info->fs_devices->latest_bdev = next_device->bdev; + list_del_rcu(&tgtdev->dev_list); + + call_rcu(&tgtdev->rcu, free_device); + + mutex_unlock(&fs_info->fs_devices->device_list_mutex); +} + int btrfs_find_device_by_path(struct btrfs_root *root, char *device_path, struct btrfs_device **device) { @@ -1931,6 +1978,98 @@ error: return ret; } +int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, + struct btrfs_device **device_out) +{ + struct request_queue *q; + struct btrfs_device *device; + struct block_device *bdev; + struct btrfs_fs_info *fs_info = root->fs_info; + struct list_head *devices; + struct rcu_string *name; + int ret = 0; + + *device_out = NULL; + if (fs_info->fs_devices->seeding) + return -EINVAL; + + bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, + fs_info->bdev_holder); + if (IS_ERR(bdev)) + return PTR_ERR(bdev); + + filemap_write_and_wait(bdev->bd_inode->i_mapping); + + devices = &fs_info->fs_devices->devices; + list_for_each_entry(device, devices, dev_list) { + if (device->bdev == bdev) { + ret = -EEXIST; + goto error; + } + } + + device = kzalloc(sizeof(*device), GFP_NOFS); + if (!device) { + ret = -ENOMEM; + goto error; + } + + name = rcu_string_strdup(device_path, GFP_NOFS); + if (!name) { + kfree(device); + ret = -ENOMEM; + goto error; + } + rcu_assign_pointer(device->name, name); + + q = bdev_get_queue(bdev); + if (blk_queue_discard(q)) + device->can_discard = 1; + mutex_lock(&root->fs_info->fs_devices->device_list_mutex); + device->writeable = 1; + device->work.func = pending_bios_fn; + generate_random_uuid(device->uuid); + device->devid = BTRFS_DEV_REPLACE_DEVID; + spin_lock_init(&device->io_lock); + device->generation = 0; + device->io_width = root->sectorsize; + device->io_align = root->sectorsize; + device->sector_size = root->sectorsize; + device->total_bytes = i_size_read(bdev->bd_inode); + device->disk_total_bytes = device->total_bytes; + device->dev_root = fs_info->dev_root; + device->bdev = bdev; + device->in_fs_metadata = 1; + device->is_tgtdev_for_dev_replace = 1; + device->mode = FMODE_EXCL; + set_blocksize(device->bdev, 4096); + device->fs_devices = fs_info->fs_devices; + list_add(&device->dev_list, &fs_info->fs_devices->devices); + fs_info->fs_devices->num_devices++; + fs_info->fs_devices->open_devices++; + if (device->can_discard) + fs_info->fs_devices->num_can_discard++; + mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); + + *device_out = device; + return ret; + +error: + blkdev_put(bdev, FMODE_EXCL); + return ret; +} + +void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, + struct btrfs_device *tgtdev) +{ + WARN_ON(fs_info->fs_devices->rw_devices == 0); + tgtdev->io_width = fs_info->dev_root->sectorsize; + tgtdev->io_align = fs_info->dev_root->sectorsize; + tgtdev->sector_size = fs_info->dev_root->sectorsize; + tgtdev->dev_root = fs_info->dev_root; + tgtdev->in_fs_metadata = 1; +} + static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, struct btrfs_device *device) { diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 8fd5a4d8acc..58d79375dea 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -286,6 +286,8 @@ struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, u8 *uuid, u8 *fsid); int btrfs_shrink_device(struct btrfs_device *device, u64 new_size); int btrfs_init_new_device(struct btrfs_root *root, char *path); +int btrfs_init_dev_replace_tgtdev(struct btrfs_root *root, char *device_path, + struct btrfs_device **device_out); int btrfs_balance(struct btrfs_balance_control *bctl, struct btrfs_ioctl_balance_args *bargs); int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info); @@ -302,6 +304,12 @@ int btrfs_get_dev_stats(struct btrfs_root *root, int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info); int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info); +void btrfs_rm_dev_replace_srcdev(struct btrfs_fs_info *fs_info, + struct btrfs_device *srcdev); +void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, + struct btrfs_device *tgtdev); +void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, + struct btrfs_device *tgtdev); int btrfs_scratch_superblock(struct btrfs_device *device); static inline void btrfs_dev_stat_inc(struct btrfs_device *dev, -- cgit v1.2.3-70-g09d2