From bedbef8ad3e75a304af6361af235302bcc61d06b Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Tue, 14 May 2024 06:39:01 +0000 Subject: [PATCH] 修改内核路径 --- kernel/fs/btrfs/dev-replace.c | 386 ++++++++++++++++++++++++++++++------------------------- 1 files changed, 211 insertions(+), 175 deletions(-) diff --git a/kernel/fs/btrfs/dev-replace.c b/kernel/fs/btrfs/dev-replace.c index 4d1d265..be6935d 100644 --- a/kernel/fs/btrfs/dev-replace.c +++ b/kernel/fs/btrfs/dev-replace.c @@ -9,6 +9,7 @@ #include <linux/blkdev.h> #include <linux/kthread.h> #include <linux/math64.h> +#include "misc.h" #include "ctree.h" #include "extent_map.h" #include "disk-io.h" @@ -21,12 +22,48 @@ #include "dev-replace.h" #include "sysfs.h" +/* + * Device replace overview + * + * [Objective] + * To copy all extents (both new and on-disk) from source device to target + * device, while still keeping the filesystem read-write. + * + * [Method] + * There are two main methods involved: + * + * - Write duplication + * + * All new writes will be written to both target and source devices, so even + * if replace gets canceled, sources device still contans up-to-date data. + * + * Location: handle_ops_on_dev_replace() from __btrfs_map_block() + * Start: btrfs_dev_replace_start() + * End: btrfs_dev_replace_finishing() + * Content: Latest data/metadata + * + * - Copy existing extents + * + * This happens by re-using scrub facility, as scrub also iterates through + * existing extents from commit root. + * + * Location: scrub_write_block_to_dev_replace() from + * scrub_block_complete() + * Content: Data/meta from commit root. + * + * Due to the content difference, we need to avoid nocow write when dev-replace + * is happening. This is done by marking the block group read-only and waiting + * for NOCOW writes. + * + * After replace is done, the finishing part is done by swapping the target and + * source devices. + * + * Location: btrfs_dev_replace_update_device_in_mapping_tree() from + * btrfs_dev_replace_finishing() + */ + 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_kthread(void *data); int btrfs_init_dev_replace(struct btrfs_fs_info *fs_info) @@ -67,10 +104,9 @@ } ret = 0; dev_replace->replace_state = - BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED; + BTRFS_IOCTL_DEV_REPLACE_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); @@ -125,7 +161,7 @@ if (btrfs_find_device(fs_info->fs_devices, BTRFS_DEV_REPLACE_DEVID, NULL, NULL, false)) { btrfs_err(fs_info, - "replace devid present without an active replace item"); +"replace without active item, run 'device scan --forget' on the target device"); ret = -EUCLEAN; } else { dev_replace->srcdev = NULL; @@ -206,7 +242,6 @@ { struct btrfs_device *device; struct block_device *bdev; - struct list_head *devices; struct rcu_string *name; u64 devid = BTRFS_DEV_REPLACE_DEVID; int ret = 0; @@ -224,10 +259,9 @@ return PTR_ERR(bdev); } - filemap_write_and_wait(bdev->bd_inode->i_mapping); + sync_blockdev(bdev); - devices = &fs_info->fs_devices->devices; - list_for_each_entry(device, devices, dev_list) { + list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) { if (device->bdev == bdev) { btrfs_err(fs_info, "target device is in the filesystem!"); @@ -260,7 +294,6 @@ } rcu_assign_pointer(device->name, name); - mutex_lock(&fs_info->fs_devices->device_list_mutex); set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); device->generation = 0; device->io_width = fs_info->sectorsize; @@ -279,6 +312,8 @@ device->dev_stats_valid = 1; set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); device->fs_devices = fs_info->fs_devices; + + mutex_lock(&fs_info->fs_devices->device_list_mutex); list_add(&device->dev_list, &fs_info->fs_devices->devices); fs_info->fs_devices->num_devices++; fs_info->fs_devices->open_devices++; @@ -296,9 +331,9 @@ * 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 btrfs_run_dev_replace(struct btrfs_trans_handle *trans) { + struct btrfs_fs_info *fs_info = trans->fs_info; int ret; struct btrfs_root *dev_root = fs_info->dev_root; struct btrfs_path *path; @@ -307,13 +342,13 @@ struct btrfs_dev_replace_item *ptr; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; - btrfs_dev_replace_read_lock(dev_replace); + down_read(&dev_replace->rwsem); if (!dev_replace->is_valid || !dev_replace->item_needs_writeback) { - btrfs_dev_replace_read_unlock(dev_replace); + up_read(&dev_replace->rwsem); return 0; } - btrfs_dev_replace_read_unlock(dev_replace); + up_read(&dev_replace->rwsem); key.objectid = 0; key.type = BTRFS_DEV_REPLACE_KEY; @@ -371,7 +406,7 @@ ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_replace_item); - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); if (dev_replace->srcdev) btrfs_set_dev_replace_src_devid(eb, ptr, dev_replace->srcdev->devid); @@ -394,7 +429,7 @@ btrfs_set_dev_replace_cursor_right(eb, ptr, dev_replace->cursor_right); dev_replace->item_needs_writeback = 0; - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); btrfs_mark_buffer_dirty(eb); @@ -402,14 +437,6 @@ 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 char* btrfs_dev_name(struct btrfs_device *device) @@ -420,7 +447,7 @@ return rcu_str_deref(device->name); } -int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, +static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info, const char *tgtdev_name, u64 srcdevid, const char *srcdev_name, int read_src) { @@ -431,15 +458,17 @@ struct btrfs_device *tgt_device = NULL; struct btrfs_device *src_device = NULL; - ret = btrfs_find_device_by_devspec(fs_info, srcdevid, - srcdev_name, &src_device); - if (ret) - return ret; + src_device = btrfs_find_device_by_devspec(fs_info, srcdevid, + srcdev_name); + if (IS_ERR(src_device)) + return PTR_ERR(src_device); - ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, - src_device, &tgt_device); - if (ret) - return ret; + if (btrfs_pinned_by_swapfile(fs_info, src_device)) { + btrfs_warn_in_rcu(fs_info, + "cannot replace device %s (devid %llu) due to active swapfile", + btrfs_dev_name(src_device), src_device->devid); + return -ETXTBSY; + } /* * Here we commit the transaction to make sure commit_total_bytes @@ -454,7 +483,12 @@ return PTR_ERR(trans); } - btrfs_dev_replace_write_lock(dev_replace); + ret = btrfs_init_dev_replace_tgtdev(fs_info, tgtdev_name, + src_device, &tgt_device); + if (ret) + return ret; + + down_write(&dev_replace->rwsem); switch (dev_replace->replace_state) { case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: @@ -464,11 +498,11 @@ case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED: ASSERT(0); ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED; + up_write(&dev_replace->rwsem); goto leave; } dev_replace->cont_reading_from_srcdev_mode = read_src; - WARN_ON(!src_device); dev_replace->srcdev = src_device; dev_replace->tgtdev = tgt_device; @@ -492,23 +526,24 @@ dev_replace->item_needs_writeback = 1; atomic64_set(&dev_replace->num_write_errors, 0); atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0); - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); - ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device); + ret = btrfs_sysfs_add_device(tgt_device); if (ret) btrfs_err(fs_info, "kobj add dev failed %d", ret); btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); - /* force writing the updated state information to disk */ - trans = btrfs_start_transaction(root, 0); + /* Commit dev_replace state and reserve 1 item for it. */ + trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED; dev_replace->srcdev = NULL; dev_replace->tgtdev = NULL; + up_write(&dev_replace->rwsem); goto leave; } @@ -521,16 +556,12 @@ &dev_replace->scrub_progress, 0, 1); ret = btrfs_dev_replace_finishing(fs_info, ret); - if (ret == -EINPROGRESS) { + if (ret == -EINPROGRESS) ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS; - } else { - WARN_ON(ret); - } return ret; leave: - btrfs_dev_replace_write_unlock(dev_replace); btrfs_destroy_dev_replace_tgtdev(tgt_device); return ret; } @@ -558,8 +589,9 @@ args->start.cont_reading_from_srcdev_mode); args->result = ret; /* don't warn if EINPROGRESS, someone else might be running scrub */ - if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS) - ret = 0; + if (ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_SCRUB_INPROGRESS || + ret == BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR) + return 0; return ret; } @@ -570,8 +602,8 @@ static void btrfs_rm_dev_replace_blocked(struct btrfs_fs_info *fs_info) { set_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); - wait_event(fs_info->replace_wait, !percpu_counter_sum( - &fs_info->bio_counter)); + wait_event(fs_info->dev_replace.replace_wait, !percpu_counter_sum( + &fs_info->dev_replace.bio_counter)); } /* @@ -580,7 +612,64 @@ static void btrfs_rm_dev_replace_unblocked(struct btrfs_fs_info *fs_info) { clear_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state); - wake_up(&fs_info->replace_wait); + wake_up(&fs_info->dev_replace.replace_wait); +} + +/* + * When finishing the device replace, before swapping the source device with the + * target device we must update the chunk allocation state in the target device, + * as it is empty because replace works by directly copying the chunks and not + * through the normal chunk allocation path. + */ +static int btrfs_set_target_alloc_state(struct btrfs_device *srcdev, + struct btrfs_device *tgtdev) +{ + struct extent_state *cached_state = NULL; + u64 start = 0; + u64 found_start; + u64 found_end; + int ret = 0; + + lockdep_assert_held(&srcdev->fs_info->chunk_mutex); + + while (!find_first_extent_bit(&srcdev->alloc_state, start, + &found_start, &found_end, + CHUNK_ALLOCATED, &cached_state)) { + ret = set_extent_bits(&tgtdev->alloc_state, found_start, + found_end, CHUNK_ALLOCATED); + if (ret) + break; + start = found_end + 1; + } + + free_extent_state(cached_state); + return 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) +{ + struct extent_map_tree *em_tree = &fs_info->mapping_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 = em->map_lookup; + 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_finishing(struct btrfs_fs_info *fs_info, @@ -597,50 +686,62 @@ /* don't allow cancel or unmount to disturb the finishing procedure */ mutex_lock(&dev_replace->lock_finishing_cancel_unmount); - btrfs_dev_replace_read_lock(dev_replace); + down_read(&dev_replace->rwsem); /* was the operation canceled, or is it finished? */ if (dev_replace->replace_state != BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) { - btrfs_dev_replace_read_unlock(dev_replace); + up_read(&dev_replace->rwsem); mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); return 0; } tgt_device = dev_replace->tgtdev; src_device = dev_replace->srcdev; - btrfs_dev_replace_read_unlock(dev_replace); + up_read(&dev_replace->rwsem); /* * flush all outstanding I/O and inode extent mappings before the * copy operation is declared as being finished */ - ret = btrfs_start_delalloc_roots(fs_info, -1); + ret = btrfs_start_delalloc_roots(fs_info, U64_MAX, false); if (ret) { mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); return ret; } btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); + if (!scrub_ret) + btrfs_reada_remove_dev(src_device); + + /* + * We have to use this loop approach because at this point src_device + * has to be available for transaction commit to complete, yet new + * chunks shouldn't be allocated on the device. + */ while (1) { trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { + btrfs_reada_undo_remove_dev(src_device); mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); return PTR_ERR(trans); } ret = btrfs_commit_transaction(trans); WARN_ON(ret); - /* keep away write_all_supers() during the finishing procedure */ + + /* Prevent write_all_supers() during the finishing procedure */ mutex_lock(&fs_info->fs_devices->device_list_mutex); + /* Prevent new chunks being allocated on the source device */ mutex_lock(&fs_info->chunk_mutex); - if (src_device->has_pending_chunks) { - mutex_unlock(&root->fs_info->chunk_mutex); - mutex_unlock(&root->fs_info->fs_devices->device_list_mutex); + + if (!list_empty(&src_device->post_commit_list)) { + mutex_unlock(&fs_info->fs_devices->device_list_mutex); + mutex_unlock(&fs_info->chunk_mutex); } else { break; } } - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); dev_replace->replace_state = scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED : BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED; @@ -649,20 +750,29 @@ dev_replace->time_stopped = ktime_get_real_seconds(); dev_replace->item_needs_writeback = 1; - /* replace old device with new one in mapping tree */ + /* + * Update allocation state in the new device and replace the old device + * with the new one in the mapping tree. + */ if (!scrub_ret) { + scrub_ret = btrfs_set_target_alloc_state(src_device, tgt_device); + if (scrub_ret) + goto error; btrfs_dev_replace_update_device_in_mapping_tree(fs_info, src_device, tgt_device); } else { - btrfs_err_in_rcu(fs_info, + if (scrub_ret != -ECANCELED) + btrfs_err_in_rcu(fs_info, "btrfs_scrub_dev(%s, %llu, %s) failed %d", btrfs_dev_name(src_device), src_device->devid, rcu_str_deref(tgt_device->name), scrub_ret); - btrfs_dev_replace_write_unlock(dev_replace); +error: + up_write(&dev_replace->rwsem); mutex_unlock(&fs_info->chunk_mutex); mutex_unlock(&fs_info->fs_devices->device_list_mutex); + btrfs_reada_undo_remove_dev(src_device); btrfs_rm_dev_replace_blocked(fs_info); if (tgt_device) btrfs_destroy_dev_replace_tgtdev(tgt_device); @@ -687,8 +797,6 @@ btrfs_device_set_disk_total_bytes(tgt_device, src_device->disk_total_bytes); btrfs_device_set_bytes_used(tgt_device, src_device->bytes_used); - ASSERT(list_empty(&src_device->resized_list)); - tgt_device->commit_total_bytes = src_device->commit_total_bytes; tgt_device->commit_bytes_used = src_device->bytes_used; btrfs_assign_next_active_device(src_device, tgt_device); @@ -696,8 +804,7 @@ list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list); fs_info->fs_devices->rw_devices++; - btrfs_dev_replace_write_unlock(dev_replace); - + up_write(&dev_replace->rwsem); btrfs_rm_dev_replace_blocked(fs_info); btrfs_rm_dev_replace_remove_srcdev(src_device); @@ -721,8 +828,11 @@ mutex_unlock(&fs_info->fs_devices->device_list_mutex); /* replace the sysfs entry */ - btrfs_sysfs_rm_device_link(fs_info->fs_devices, src_device); - btrfs_rm_dev_replace_free_srcdev(fs_info, src_device); + btrfs_sysfs_remove_device(src_device); + btrfs_sysfs_update_devid(tgt_device); + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &src_device->dev_state)) + btrfs_scratch_superblocks(fs_info, src_device->bdev, + src_device->name->str); /* write back the superblocks */ trans = btrfs_start_transaction(root, 0); @@ -731,33 +841,9 @@ mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); + btrfs_rm_dev_replace_free_srcdev(src_device); + 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 = em->map_lookup; - 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); } /* @@ -794,7 +880,7 @@ { struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; - btrfs_dev_replace_read_lock(dev_replace); + down_read(&dev_replace->rwsem); /* 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; @@ -806,7 +892,7 @@ args->status.num_uncorrectable_read_errors = atomic64_read(&dev_replace->num_uncorrectable_read_errors); args->status.progress_1000 = btrfs_dev_replace_progress(fs_info); - btrfs_dev_replace_read_unlock(dev_replace); + up_read(&dev_replace->rwsem); } int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info) @@ -823,18 +909,18 @@ return -EROFS; mutex_lock(&dev_replace->lock_finishing_cancel_unmount); - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); 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_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); break; case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: tgt_device = dev_replace->tgtdev; src_device = dev_replace->srcdev; - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); ret = btrfs_scrub_cancel(fs_info); if (ret < 0) { result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED; @@ -865,8 +951,9 @@ dev_replace->time_stopped = ktime_get_real_seconds(); dev_replace->item_needs_writeback = 1; - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); + /* Scrub for replace must not be running in suspended state */ btrfs_scrub_cancel(fs_info); trans = btrfs_start_transaction(root, 0); @@ -886,6 +973,7 @@ btrfs_destroy_dev_replace_tgtdev(tgt_device); break; default: + up_write(&dev_replace->rwsem); result = -EINVAL; } @@ -898,7 +986,8 @@ struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; mutex_lock(&dev_replace->lock_finishing_cancel_unmount); - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); + switch (dev_replace->replace_state) { case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED: case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED: @@ -914,7 +1003,7 @@ break; } - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); mutex_unlock(&dev_replace->lock_finishing_cancel_unmount); } @@ -924,12 +1013,13 @@ struct task_struct *task; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; - btrfs_dev_replace_write_lock(dev_replace); + down_write(&dev_replace->rwsem); + 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_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); return 0; case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED: break; @@ -945,21 +1035,21 @@ "you may cancel the operation after 'mount -o degraded'"); dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); return 0; } - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); /* * This could collide with a paused balance, but the exclusive op logic * should never allow both to start and pause. We don't want to allow * dev-replace to start anyway. */ - if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) { - btrfs_dev_replace_write_lock(dev_replace); + if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) { + down_write(&dev_replace->rwsem); dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED; - btrfs_dev_replace_write_unlock(dev_replace); + up_write(&dev_replace->rwsem); btrfs_info(fs_info, "cannot resume dev-replace, other exclusive operation running"); return 0; @@ -990,13 +1080,13 @@ btrfs_device_get_total_bytes(dev_replace->srcdev), &dev_replace->scrub_progress, 0, 1); ret = btrfs_dev_replace_finishing(fs_info, ret); - WARN_ON(ret); + WARN_ON(ret && ret != -ECANCELED); - clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags); + btrfs_exclop_finish(fs_info); return 0; } -int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) +int __pure btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace) { if (!dev_replace->is_valid) return 0; @@ -1013,7 +1103,7 @@ * 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 + * not called and the filesystem is remounted * in degraded state. This does not stop the * dev_replace procedure. It needs to be canceled * manually if the cancellation is wanted. @@ -1023,81 +1113,27 @@ return 1; } -void btrfs_dev_replace_read_lock(struct btrfs_dev_replace *dev_replace) -{ - read_lock(&dev_replace->lock); - atomic_inc(&dev_replace->read_locks); -} - -void btrfs_dev_replace_read_unlock(struct btrfs_dev_replace *dev_replace) -{ - ASSERT(atomic_read(&dev_replace->read_locks) > 0); - atomic_dec(&dev_replace->read_locks); - read_unlock(&dev_replace->lock); -} - -void btrfs_dev_replace_write_lock(struct btrfs_dev_replace *dev_replace) -{ -again: - wait_event(dev_replace->read_lock_wq, - atomic_read(&dev_replace->blocking_readers) == 0); - write_lock(&dev_replace->lock); - if (atomic_read(&dev_replace->blocking_readers)) { - write_unlock(&dev_replace->lock); - goto again; - } -} - -void btrfs_dev_replace_write_unlock(struct btrfs_dev_replace *dev_replace) -{ - ASSERT(atomic_read(&dev_replace->blocking_readers) == 0); - write_unlock(&dev_replace->lock); -} - -/* inc blocking cnt and release read lock */ -void btrfs_dev_replace_set_lock_blocking( - struct btrfs_dev_replace *dev_replace) -{ - /* only set blocking for read lock */ - ASSERT(atomic_read(&dev_replace->read_locks) > 0); - atomic_inc(&dev_replace->blocking_readers); - read_unlock(&dev_replace->lock); -} - -/* acquire read lock and dec blocking cnt */ -void btrfs_dev_replace_clear_lock_blocking( - struct btrfs_dev_replace *dev_replace) -{ - /* only set blocking for read lock */ - ASSERT(atomic_read(&dev_replace->read_locks) > 0); - ASSERT(atomic_read(&dev_replace->blocking_readers) > 0); - read_lock(&dev_replace->lock); - /* Barrier implied by atomic_dec_and_test */ - if (atomic_dec_and_test(&dev_replace->blocking_readers)) - cond_wake_up_nomb(&dev_replace->read_lock_wq); -} - void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info) { - percpu_counter_inc(&fs_info->bio_counter); + percpu_counter_inc(&fs_info->dev_replace.bio_counter); } void btrfs_bio_counter_sub(struct btrfs_fs_info *fs_info, s64 amount) { - percpu_counter_sub(&fs_info->bio_counter, amount); - cond_wake_up_nomb(&fs_info->replace_wait); + percpu_counter_sub(&fs_info->dev_replace.bio_counter, amount); + cond_wake_up_nomb(&fs_info->dev_replace.replace_wait); } void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info) { while (1) { - percpu_counter_inc(&fs_info->bio_counter); + percpu_counter_inc(&fs_info->dev_replace.bio_counter); if (likely(!test_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state))) break; btrfs_bio_counter_dec(fs_info); - wait_event(fs_info->replace_wait, + wait_event(fs_info->dev_replace.replace_wait, !test_bit(BTRFS_FS_STATE_DEV_REPLACING, &fs_info->fs_state)); } -- Gitblit v1.6.2