diff options
Diffstat (limited to 'fs/btrfs/volumes.c')
| -rw-r--r-- | fs/btrfs/volumes.c | 690 |
1 files changed, 406 insertions, 284 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 49810b70afd3..b5036bd69e6a 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -145,6 +145,71 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, struct btrfs_bio **bbio_ret, int mirror_num, int need_raid_map); +/* + * Device locking + * ============== + * + * There are several mutexes that protect manipulation of devices and low-level + * structures like chunks but not block groups, extents or files + * + * uuid_mutex (global lock) + * ------------------------ + * protects the fs_uuids list that tracks all per-fs fs_devices, resulting from + * the SCAN_DEV ioctl registration or from mount either implicitly (the first + * device) or requested by the device= mount option + * + * the mutex can be very coarse and can cover long-running operations + * + * protects: updates to fs_devices counters like missing devices, rw devices, + * seeding, structure cloning, openning/closing devices at mount/umount time + * + * global::fs_devs - add, remove, updates to the global list + * + * does not protect: manipulation of the fs_devices::devices list! + * + * btrfs_device::name - renames (write side), read is RCU + * + * fs_devices::device_list_mutex (per-fs, with RCU) + * ------------------------------------------------ + * protects updates to fs_devices::devices, ie. adding and deleting + * + * simple list traversal with read-only actions can be done with RCU protection + * + * may be used to exclude some operations from running concurrently without any + * modifications to the list (see write_all_supers) + * + * volume_mutex + * ------------ + * coarse lock owned by a mounted filesystem; used to exclude some operations + * that cannot run in parallel and affect the higher-level properties of the + * filesystem like: device add/deleting/resize/replace, or balance + * + * balance_mutex + * ------------- + * protects balance structures (status, state) and context accessed from + * several places (internally, ioctl) + * + * chunk_mutex + * ----------- + * protects chunks, adding or removing during allocation, trim or when a new + * device is added/removed + * + * cleaner_mutex + * ------------- + * a big lock that is held by the cleaner thread and prevents running subvolume + * cleaning together with relocation or delayed iputs + * + * + * Lock nesting + * ============ + * + * uuid_mutex + * volume_mutex + * device_list_mutex + * chunk_mutex + * balance_mutex + */ + DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); struct list_head *btrfs_get_fs_uuids(void) @@ -180,6 +245,13 @@ static struct btrfs_fs_devices *alloc_fs_devices(const u8 *fsid) return fs_devs; } +static void free_device(struct btrfs_device *device) +{ + rcu_string_free(device->name); + bio_put(device->flush_bio); + kfree(device); +} + static void free_fs_devices(struct btrfs_fs_devices *fs_devices) { struct btrfs_device *device; @@ -188,9 +260,7 @@ static void free_fs_devices(struct btrfs_fs_devices *fs_devices) device = list_entry(fs_devices->devices.next, struct btrfs_device, dev_list); list_del(&device->dev_list); - rcu_string_free(device->name); - bio_put(device->flush_bio); - kfree(device); + free_device(device); } kfree(fs_devices); } @@ -220,6 +290,11 @@ void btrfs_cleanup_fs_uuids(void) } } +/* + * Returns a pointer to a new btrfs_device on success; ERR_PTR() on error. + * Returned struct is not linked onto any lists and must be destroyed using + * free_device. + */ static struct btrfs_device *__alloc_device(void) { struct btrfs_device *dev; @@ -237,7 +312,6 @@ static struct btrfs_device *__alloc_device(void) kfree(dev); return ERR_PTR(-ENOMEM); } - bio_get(dev->flush_bio); INIT_LIST_HEAD(&dev->dev_list); INIT_LIST_HEAD(&dev->dev_alloc_list); @@ -245,7 +319,6 @@ static struct btrfs_device *__alloc_device(void) spin_lock_init(&dev->io_lock); - spin_lock_init(&dev->reada_lock); atomic_set(&dev->reada_in_flight, 0); atomic_set(&dev->dev_stats_ccnt, 0); btrfs_device_data_ordered_init(dev); @@ -531,45 +604,42 @@ static void pending_bios_fn(struct btrfs_work *work) run_scheduled_bios(device); } - -static void btrfs_free_stale_device(struct btrfs_device *cur_dev) +/* + * Search and remove all stale (devices which are not mounted) devices. + * When both inputs are NULL, it will search and release all stale devices. + * path: Optional. When provided will it release all unmounted devices + * matching this path only. + * skip_dev: Optional. Will skip this device when searching for the stale + * devices. + */ +static void btrfs_free_stale_devices(const char *path, + struct btrfs_device *skip_dev) { - struct btrfs_fs_devices *fs_devs; - struct btrfs_device *dev; - - if (!cur_dev->name) - return; + struct btrfs_fs_devices *fs_devs, *tmp_fs_devs; + struct btrfs_device *dev, *tmp_dev; - list_for_each_entry(fs_devs, &fs_uuids, list) { - int del = 1; + list_for_each_entry_safe(fs_devs, tmp_fs_devs, &fs_uuids, list) { if (fs_devs->opened) continue; - if (fs_devs->seeding) - continue; - list_for_each_entry(dev, &fs_devs->devices, dev_list) { + list_for_each_entry_safe(dev, tmp_dev, + &fs_devs->devices, dev_list) { + int not_found = 0; - if (dev == cur_dev) + if (skip_dev && skip_dev == dev) continue; - if (!dev->name) + if (path && !dev->name) continue; - /* - * Todo: This won't be enough. What if the same device - * comes back (with new uuid and) with its mapper path? - * But for now, this does help as mostly an admin will - * either use mapper or non mapper path throughout. - */ rcu_read_lock(); - del = strcmp(rcu_str_deref(dev->name), - rcu_str_deref(cur_dev->name)); + if (path) + not_found = strcmp(rcu_str_deref(dev->name), + path); rcu_read_unlock(); - if (!del) - break; - } + if (not_found) + continue; - if (!del) { /* delete the stale device */ if (fs_devs->num_devices == 1) { btrfs_sysfs_remove_fsid(fs_devs); @@ -578,38 +648,99 @@ static void btrfs_free_stale_device(struct btrfs_device *cur_dev) } else { fs_devs->num_devices--; list_del(&dev->dev_list); - rcu_string_free(dev->name); - bio_put(dev->flush_bio); - kfree(dev); + free_device(dev); } - break; } } } +static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices, + struct btrfs_device *device, fmode_t flags, + void *holder) +{ + struct request_queue *q; + struct block_device *bdev; + struct buffer_head *bh; + struct btrfs_super_block *disk_super; + u64 devid; + int ret; + + if (device->bdev) + return -EINVAL; + if (!device->name) + return -EINVAL; + + ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, + &bdev, &bh); + if (ret) + return ret; + + disk_super = (struct btrfs_super_block *)bh->b_data; + devid = btrfs_stack_device_id(&disk_super->dev_item); + if (devid != device->devid) + goto error_brelse; + + if (memcmp(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE)) + goto error_brelse; + + device->generation = btrfs_super_generation(disk_super); + + if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { + clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); + fs_devices->seeding = 1; + } else { + if (bdev_read_only(bdev)) + clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); + else + set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); + } + + q = bdev_get_queue(bdev); + if (!blk_queue_nonrot(q)) + fs_devices->rotating = 1; + + device->bdev = bdev; + clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); + device->mode = flags; + + fs_devices->open_devices++; + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && + device->devid != BTRFS_DEV_REPLACE_DEVID) { + fs_devices->rw_devices++; + list_add(&device->dev_alloc_list, &fs_devices->alloc_list); + } + brelse(bh); + + return 0; + +error_brelse: + brelse(bh); + blkdev_put(bdev, flags); + + return -EINVAL; +} + /* * Add new device to list of registered devices * * Returns: - * 1 - first time device is seen - * 0 - device already known - * < 0 - error + * device pointer which was just added or updated when successful + * error pointer when failed */ -static noinline int device_list_add(const char *path, - struct btrfs_super_block *disk_super, - u64 devid, struct btrfs_fs_devices **fs_devices_ret) +static noinline struct btrfs_device *device_list_add(const char *path, + struct btrfs_super_block *disk_super) { struct btrfs_device *device; struct btrfs_fs_devices *fs_devices; struct rcu_string *name; - int ret = 0; u64 found_transid = btrfs_super_generation(disk_super); + u64 devid = btrfs_stack_device_id(&disk_super->dev_item); fs_devices = find_fsid(disk_super->fsid); if (!fs_devices) { fs_devices = alloc_fs_devices(disk_super->fsid); if (IS_ERR(fs_devices)) - return PTR_ERR(fs_devices); + return ERR_CAST(fs_devices); list_add(&fs_devices->list, &fs_uuids); @@ -621,20 +752,19 @@ static noinline int device_list_add(const char *path, if (!device) { if (fs_devices->opened) - return -EBUSY; + return ERR_PTR(-EBUSY); device = btrfs_alloc_device(NULL, &devid, disk_super->dev_item.uuid); if (IS_ERR(device)) { /* we can safely leave the fs_devices entry around */ - return PTR_ERR(device); + return device; } name = rcu_string_strdup(path, GFP_NOFS); if (!name) { - bio_put(device->flush_bio); - kfree(device); - return -ENOMEM; + free_device(device); + return ERR_PTR(-ENOMEM); } rcu_assign_pointer(device->name, name); @@ -643,8 +773,16 @@ static noinline int device_list_add(const char *path, fs_devices->num_devices++; mutex_unlock(&fs_devices->device_list_mutex); - ret = 1; device->fs_devices = fs_devices; + btrfs_free_stale_devices(path, device); + + if (disk_super->label[0]) + pr_info("BTRFS: device label %s devid %llu transid %llu %s\n", + disk_super->label, devid, found_transid, path); + else + pr_info("BTRFS: device fsid %pU devid %llu transid %llu %s\n", + disk_super->fsid, devid, found_transid, path); + } else if (!device->name || strcmp(device->name->str, path)) { /* * When FS is already mounted. @@ -680,17 +818,17 @@ static noinline int device_list_add(const char *path, * with larger generation number or the last-in if * generation are equal. */ - return -EEXIST; + return ERR_PTR(-EEXIST); } name = rcu_string_strdup(path, GFP_NOFS); if (!name) - return -ENOMEM; + return ERR_PTR(-ENOMEM); rcu_string_free(device->name); rcu_assign_pointer(device->name, name); - if (device->missing) { + if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { fs_devices->missing_devices--; - device->missing = 0; + clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); } } @@ -703,16 +841,9 @@ static noinline int device_list_add(const char *path, if (!fs_devices->opened) device->generation = found_transid; - /* - * if there is new btrfs on an already registered device, - * then remove the stale device entry. - */ - if (ret > 0) - btrfs_free_stale_device(device); - - *fs_devices_ret = fs_devices; + fs_devices->total_devices = btrfs_super_num_devices(disk_super); - return ret; + return device; } static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) @@ -745,8 +876,7 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) name = rcu_string_strdup(orig_dev->name->str, GFP_KERNEL); if (!name) { - bio_put(device->flush_bio); - kfree(device); + free_device(device); goto error; } rcu_assign_pointer(device->name, name); @@ -773,10 +903,12 @@ void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step) again: /* This is the initialized path, it is safe to release the devices. */ list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) { - if (device->in_fs_metadata) { - if (!device->is_tgtdev_for_dev_replace && - (!latest_dev || - device->generation > latest_dev->generation)) { + if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, + &device->dev_state)) { + if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, + &device->dev_state) && + (!latest_dev || + device->generation > latest_dev->generation)) { latest_dev = device; } continue; @@ -793,7 +925,8 @@ again: * not, which means whether this device is * used or whether it should be removed. */ - if (step == 0 || device->is_tgtdev_for_dev_replace) { + if (step == 0 || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, + &device->dev_state)) { continue; } } @@ -802,17 +935,16 @@ again: device->bdev = NULL; fs_devices->open_devices--; } - if (device->writeable) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { list_del_init(&device->dev_alloc_list); - device->writeable = 0; - if (!device->is_tgtdev_for_dev_replace) + clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); + if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT, + &device->dev_state)) fs_devices->rw_devices--; } list_del_init(&device->dev_list); fs_devices->num_devices--; - rcu_string_free(device->name); - bio_put(device->flush_bio); - kfree(device); + free_device(device); } if (fs_devices->seed) { @@ -825,35 +957,25 @@ again: mutex_unlock(&uuid_mutex); } -static void __free_device(struct work_struct *work) -{ - struct btrfs_device *device; - - device = container_of(work, struct btrfs_device, rcu_work); - rcu_string_free(device->name); - bio_put(device->flush_bio); - kfree(device); -} - -static void free_device(struct rcu_head *head) +static void free_device_rcu(struct rcu_head *head) { struct btrfs_device *device; device = container_of(head, struct btrfs_device, rcu); - - INIT_WORK(&device->rcu_work, __free_device); - schedule_work(&device->rcu_work); + free_device(device); } static void btrfs_close_bdev(struct btrfs_device *device) { - if (device->bdev && device->writeable) { + if (!device->bdev) + return; + + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { sync_blockdev(device->bdev); invalidate_bdev(device->bdev); } - if (device->bdev) - blkdev_put(device->bdev, device->mode); + blkdev_put(device->bdev, device->mode); } static void btrfs_prepare_close_one_device(struct btrfs_device *device) @@ -865,13 +987,13 @@ static void btrfs_prepare_close_one_device(struct btrfs_device *device) if (device->bdev) fs_devices->open_devices--; - if (device->writeable && + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && device->devid != BTRFS_DEV_REPLACE_DEVID) { list_del_init(&device->dev_alloc_list); fs_devices->rw_devices--; } - if (device->missing) + if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) fs_devices->missing_devices--; new_device = btrfs_alloc_device(NULL, &device->devid, @@ -917,7 +1039,7 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) struct btrfs_device, dev_list); list_del(&device->dev_list); btrfs_close_bdev(device); - call_rcu(&device->rcu, free_device); + call_rcu(&device->rcu, free_device_rcu); } WARN_ON(fs_devices->open_devices); @@ -947,93 +1069,32 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices) __btrfs_close_devices(fs_devices); free_fs_devices(fs_devices); } - /* - * Wait for rcu kworkers under __btrfs_close_devices - * to finish all blkdev_puts so device is really - * free when umount is done. - */ - rcu_barrier(); return ret; } static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, fmode_t flags, void *holder) { - struct request_queue *q; - struct block_device *bdev; struct list_head *head = &fs_devices->devices; struct btrfs_device *device; struct btrfs_device *latest_dev = NULL; - struct buffer_head *bh; - struct btrfs_super_block *disk_super; - u64 devid; - int seeding = 1; int ret = 0; flags |= FMODE_EXCL; list_for_each_entry(device, head, dev_list) { - if (device->bdev) - continue; - if (!device->name) - continue; - /* Just open everything we can; ignore failures here */ - if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1, - &bdev, &bh)) + if (btrfs_open_one_device(fs_devices, device, flags, holder)) continue; - disk_super = (struct btrfs_super_block *)bh->b_data; - devid = btrfs_stack_device_id(&disk_super->dev_item); - if (devid != device->devid) - goto error_brelse; - - if (memcmp(device->uuid, disk_super->dev_item.uuid, - BTRFS_UUID_SIZE)) - goto error_brelse; - - device->generation = btrfs_super_generation(disk_super); if (!latest_dev || device->generation > latest_dev->generation) latest_dev = device; - - if (btrfs_super_flags(disk_super) & BTRFS_SUPER_FLAG_SEEDING) { - device->writeable = 0; - } else { - device->writeable = !bdev_read_only(bdev); - seeding = 0; - } - - q = bdev_get_queue(bdev); - if (blk_queue_discard(q)) - device->can_discard = 1; - if (!blk_queue_nonrot(q)) - fs_devices->rotating = 1; - - device->bdev = bdev; - device->in_fs_metadata = 0; - device->mode = flags; - - fs_devices->open_devices++; - if (device->writeable && - device->devid != BTRFS_DEV_REPLACE_DEVID) { - fs_devices->rw_devices++; - list_add(&device->dev_alloc_list, - &fs_devices->alloc_list); - } - brelse(bh); - continue; - -error_brelse: - brelse(bh); - blkdev_put(bdev, flags); - continue; } if (fs_devices->open_devices == 0) { ret = -EINVAL; goto out; } - fs_devices->seeding = seeding; fs_devices->opened = 1; fs_devices->latest_bdev = latest_dev->bdev; fs_devices->total_rw_bytes = 0; @@ -1117,12 +1178,10 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, struct btrfs_fs_devices **fs_devices_ret) { struct btrfs_super_block *disk_super; + struct btrfs_device *device; struct block_device *bdev; struct page *page; - int ret = -EINVAL; - u64 devid; - u64 transid; - u64 total_devices; + int ret = 0; u64 bytenr; /* @@ -1141,26 +1200,16 @@ int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, goto error; } - if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) + if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) { + ret = -EINVAL; goto error_bdev_put; - - devid = btrfs_stack_device_id(&disk_super->dev_item); - transid = btrfs_super_generation(disk_super); - total_devices = btrfs_super_num_devices(disk_super); - - ret = device_list_add(path, disk_super, devid, fs_devices_ret); - if (ret > 0) { - if (disk_super->label[0]) { - pr_info("BTRFS: device label %s ", disk_super->label); - } else { - pr_info("BTRFS: device fsid %pU ", disk_super->fsid); - } - - pr_cont("devid %llu transid %llu %s\n", devid, transid, path); - ret = 0; } - if (!ret && fs_devices_ret) - (*fs_devices_ret)->total_devices = total_devices; + + device = device_list_add(path, disk_super); + if (IS_ERR(device)) + ret = PTR_ERR(device); + else + *fs_devices_ret = device->fs_devices; btrfs_release_disk_super(page); @@ -1186,7 +1235,8 @@ int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, *length = 0; - if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace) + if (start >= device->total_bytes || + test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) return 0; path = btrfs_alloc_path(); @@ -1364,7 +1414,8 @@ int find_free_dev_extent_start(struct btrfs_transaction *transaction, max_hole_size = 0; again: - if (search_start >= search_end || device->is_tgtdev_for_dev_replace) { + if (search_start >= search_end || + test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { ret = -ENOSPC; goto out; } @@ -1571,8 +1622,8 @@ static int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, struct extent_buffer *leaf; struct btrfs_key key; - WARN_ON(!device->in_fs_metadata); - WARN_ON(device->is_tgtdev_for_dev_replace); + WARN_ON(!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state)); + WARN_ON(test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)); path = btrfs_alloc_path(); if (!path) return -ENOMEM; @@ -1662,7 +1713,7 @@ error: * the device information is stored in the chunk root * the btrfs_device struct should be fully filled in */ -static int btrfs_add_device(struct btrfs_trans_handle *trans, +static int btrfs_add_dev_item(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, struct btrfs_device *device) { @@ -1818,7 +1869,8 @@ static struct btrfs_device * btrfs_find_next_active_device( list_for_each_entry(next_device, &fs_devs->devices, dev_list) { if (next_device != device && - !next_device->missing && next_device->bdev) + !test_bit(BTRFS_DEV_STATE_MISSING, &next_device->dev_state) + && next_device->bdev) return next_device; } @@ -1859,6 +1911,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, u64 num_devices; int ret = 0; + mutex_lock(&fs_info->volume_mutex); mutex_lock(&uuid_mutex); num_devices = fs_info->fs_devices->num_devices; @@ -1878,17 +1931,18 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, if (ret) goto out; - if (device->is_tgtdev_for_dev_replace) { + if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { ret = BTRFS_ERROR_DEV_TGT_REPLACE; goto out; } - if (device->writeable && fs_info->fs_devices->rw_devices == 1) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && + fs_info->fs_devices->rw_devices == 1) { ret = BTRFS_ERROR_DEV_ONLY_WRITABLE; goto out; } - if (device->writeable) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { mutex_lock(&fs_info->chunk_mutex); list_del_init(&device->dev_alloc_list); device->fs_devices->rw_devices--; @@ -1910,7 +1964,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, if (ret) goto error_undo; - device->in_fs_metadata = 0; + clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); btrfs_scrub_cancel_dev(fs_info, device); /* @@ -1930,7 +1984,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, device->fs_devices->num_devices--; device->fs_devices->total_devices--; - if (device->missing) + if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) device->fs_devices->missing_devices--; btrfs_assign_next_active_device(fs_info, device, NULL); @@ -1950,11 +2004,11 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, * the devices list. All that's left is to zero out the old * supers and free the device. */ - if (device->writeable) + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) btrfs_scratch_superblocks(device->bdev, device->name->str); btrfs_close_bdev(device); - call_rcu(&device->rcu, free_device); + call_rcu(&device->rcu, free_device_rcu); if (cur_devices->open_devices == 0) { struct btrfs_fs_devices *fs_devices; @@ -1973,10 +2027,11 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info, const char *device_path, out: mutex_unlock(&uuid_mutex); + mutex_unlock(&fs_info->volume_mutex); return ret; error_undo: - if (device->writeable) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { mutex_lock(&fs_info->chunk_mutex); list_add(&device->dev_alloc_list, &fs_info->fs_devices->alloc_list); @@ -2004,10 +2059,10 @@ void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info, list_del_rcu(&srcdev->dev_list); list_del(&srcdev->dev_alloc_list); fs_devices->num_devices--; - if (srcdev->missing) + if (test_bit(BTRFS_DEV_STATE_MISSING, &srcdev->dev_state)) fs_devices->missing_devices--; - if (srcdev->writeable) + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state)) fs_devices->rw_devices--; if (srcdev->bdev) @@ -2019,13 +2074,13 @@ void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info, { struct btrfs_fs_devices *fs_devices = srcdev->fs_devices; - if (srcdev->writeable) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &srcdev->dev_state)) { /* zero out the old super if it is writable */ btrfs_scratch_superblocks(srcdev->bdev, srcdev->name->str); } btrfs_close_bdev(srcdev); - call_rcu(&srcdev->rcu, free_device); + call_rcu(&srcdev->rcu, free_device_rcu); /* if this is no devs we rather delete the fs_devices */ if (!fs_devices->num_devices) { @@ -2084,7 +2139,7 @@ void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, btrfs_scratch_superblocks(tgtdev->bdev, tgtdev->name->str); btrfs_close_bdev(tgtdev); - call_rcu(&tgtdev->rcu, free_device); + call_rcu(&tgtdev->rcu, free_device_rcu); } static int btrfs_find_device_by_path(struct btrfs_fs_info *fs_info, @@ -2129,7 +2184,8 @@ int btrfs_find_device_missing_or_by_path(struct btrfs_fs_info *fs_info, * is held by the caller. */ list_for_each_entry(tmp, devices, dev_list) { - if (tmp->in_fs_metadata && !tmp->bdev) { + if (test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, + &tmp->dev_state) && !tmp->bdev) { *device = tmp; break; } @@ -2358,26 +2414,19 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path name = rcu_string_strdup(device_path, GFP_KERNEL); if (!name) { - bio_put(device->flush_bio); - kfree(device); ret = -ENOMEM; - goto error; + goto error_free_device; } rcu_assign_pointer(device->name, name); trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { - rcu_string_free(device->name); - bio_put(device->flush_bio); - kfree(device); ret = PTR_ERR(trans); - goto error; + goto error_free_device; } q = bdev_get_queue(bdev); - if (blk_queue_discard(q)) - device->can_discard = 1; - device->writeable = 1; + set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); device->generation = trans->transid; device->io_width = fs_info->sectorsize; device->io_align = fs_info->sectorsize; @@ -2388,8 +2437,8 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path device->commit_total_bytes = device->total_bytes; device->fs_info = fs_info; device->bdev = bdev; - device->in_fs_metadata = 1; - device->is_tgtdev_for_dev_replace = 0; + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); + clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); device->mode = FMODE_EXCL; device->dev_stats_valid = 1; set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); @@ -2450,7 +2499,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path } } - ret = btrfs_add_device(trans, fs_info, device); + ret = btrfs_add_dev_item(trans, fs_info, device); if (ret) { btrfs_abort_transaction(trans, ret); goto error_sysfs; @@ -2511,9 +2560,8 @@ error_trans: sb->s_flags |= SB_RDONLY; if (trans) btrfs_end_transaction(trans); - rcu_string_free(device->name); - bio_put(device->flush_bio); - kfree(device); +error_free_device: + free_device(device); error: blkdev_put(bdev, FMODE_EXCL); if (seeding_dev && !unlocked) { @@ -2528,7 +2576,6 @@ int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, struct btrfs_device *srcdev, struct btrfs_device **device_out) { - struct request_queue *q; struct btrfs_device *device; struct block_device *bdev; struct list_head *devices; @@ -2579,18 +2626,14 @@ int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, name = rcu_string_strdup(device_path, GFP_KERNEL); if (!name) { - bio_put(device->flush_bio); - kfree(device); + free_device(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(&fs_info->fs_devices->device_list_mutex); - device->writeable = 1; + set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state); device->generation = 0; device->io_width = fs_info->sectorsize; device->io_align = fs_info->sectorsize; @@ -2603,8 +2646,8 @@ int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, device->commit_bytes_used = device->bytes_used; device->fs_info = fs_info; device->bdev = bdev; - device->in_fs_metadata = 1; - device->is_tgtdev_for_dev_replace = 1; + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); + set_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); device->mode = FMODE_EXCL; device->dev_stats_valid = 1; set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE); @@ -2632,7 +2675,7 @@ void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, tgtdev->io_align = sectorsize; tgtdev->sector_size = sectorsize; tgtdev->fs_info = fs_info; - tgtdev->in_fs_metadata = 1; + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &tgtdev->dev_state); } static noinline int btrfs_update_device(struct btrfs_trans_handle *trans, @@ -2690,7 +2733,7 @@ int btrfs_grow_device(struct btrfs_trans_handle *trans, u64 old_total; u64 diff; - if (!device->writeable) + if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) return -EACCES; new_size = round_down(new_size, fs_info->sectorsize); @@ -2700,7 +2743,7 @@ int btrfs_grow_device(struct btrfs_trans_handle *trans, diff = round_down(new_size - device->total_bytes, fs_info->sectorsize); if (new_size <= device->total_bytes || - device->is_tgtdev_for_dev_replace) { + test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { mutex_unlock(&fs_info->chunk_mutex); return -EINVAL; } @@ -3044,6 +3087,48 @@ error: return ret; } +/* + * return 1 : allocate a data chunk successfully, + * return <0: errors during allocating a data chunk, + * return 0 : no need to allocate a data chunk. + */ +static int btrfs_may_alloc_data_chunk(struct btrfs_fs_info *fs_info, + u64 chunk_offset) +{ + struct btrfs_block_group_cache *cache; + u64 bytes_used; + u64 chunk_type; + + cache = btrfs_lookup_block_group(fs_info, chunk_offset); + ASSERT(cache); + chunk_type = cache->flags; + btrfs_put_block_group(cache); + + if (chunk_type & BTRFS_BLOCK_GROUP_DATA) { + spin_lock(&fs_info->data_sinfo->lock); + bytes_used = fs_info->data_sinfo->bytes_used; + spin_unlock(&fs_info->data_sinfo->lock); + + if (!bytes_used) { + struct btrfs_trans_handle *trans; + int ret; + + trans = btrfs_join_transaction(fs_info->tree_root); + if (IS_ERR(trans)) + return PTR_ERR(trans); + + ret = btrfs_force_chunk_alloc(trans, fs_info, + BTRFS_BLOCK_GROUP_DATA); + btrfs_end_transaction(trans); + if (ret < 0) + return ret; + + return 1; + } + } + return 0; +} + static int insert_balance_item(struct btrfs_fs_info *fs_info, struct btrfs_balance_control *bctl) { @@ -3502,7 +3587,6 @@ static int __btrfs_balance(struct btrfs_fs_info *fs_info) u32 count_meta = 0; u32 count_sys = 0; int chunk_reserved = 0; - u64 bytes_used = 0; /* step one make some room on all the devices */ devices = &fs_info->fs_devices->devices; @@ -3510,10 +3594,10 @@ static int __btrfs_balance(struct btrfs_fs_info *fs_info) old_size = btrfs_device_get_total_bytes(device); size_to_free = div_factor(old_size, 1); size_to_free = min_t(u64, size_to_free, SZ_1M); - if (!device->writeable || + if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) || btrfs_device_get_total_bytes(device) - btrfs_device_get_bytes_used(device) > size_to_free || - device->is_tgtdev_for_dev_replace) + test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) continue; ret = btrfs_shrink_device(device, old_size - size_to_free); @@ -3661,28 +3745,21 @@ again: goto loop; } - ASSERT(fs_info->data_sinfo); - spin_lock(&fs_info->data_sinfo->lock); - bytes_used = fs_info->data_sinfo->bytes_used; - spin_unlock(&fs_info->data_sinfo->lock); - - if ((chunk_type & BTRFS_BLOCK_GROUP_DATA) && - !chunk_reserved && !bytes_used) { - trans = btrfs_start_transaction(chunk_root, 0); - if (IS_ERR(trans)) { - mutex_unlock(&fs_info->delete_unused_bgs_mutex); - ret = PTR_ERR(trans); - goto error; - } - - ret = btrfs_force_chunk_alloc(trans, fs_info, - BTRFS_BLOCK_GROUP_DATA); - btrfs_end_transaction(trans); + if (!chunk_reserved) { + /* + * We may be relocating the only data chunk we have, + * which could potentially end up with losing data's + * raid profile, so lets allocate an empty one in + * advance. + */ + ret = btrfs_may_alloc_data_chunk(fs_info, + found_key.offset); if (ret < 0) { mutex_unlock(&fs_info->delete_unused_bgs_mutex); goto error; + } else if (ret == 1) { + chunk_reserved = 1; } - chunk_reserved = 1; } ret = btrfs_relocate_chunk(fs_info, found_key.offset); @@ -4381,7 +4458,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) new_size = round_down(new_size, fs_info->sectorsize); diff = round_down(old_size - new_size, fs_info->sectorsize); - if (device->is_tgtdev_for_dev_replace) + if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) return -EINVAL; path = btrfs_alloc_path(); @@ -4393,7 +4470,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_total_bytes(device, new_size); - if (device->writeable) { + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { device->fs_devices->total_rw_bytes -= diff; atomic64_sub(diff, &fs_info->free_chunk_space); } @@ -4445,6 +4522,18 @@ again: chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); btrfs_release_path(path); + /* + * We may be relocating the only data chunk we have, + * which could potentially end up with losing data's + * raid profile, so lets allocate an empty one in + * advance. + */ + ret = btrfs_may_alloc_data_chunk(fs_info, chunk_offset); + if (ret < 0) { + mutex_unlock(&fs_info->delete_unused_bgs_mutex); + goto done; + } + ret = btrfs_relocate_chunk(fs_info, chunk_offset); mutex_unlock(&fs_info->delete_unused_bgs_mutex); if (ret && ret != -ENOSPC) @@ -4518,7 +4607,7 @@ done: if (ret) { mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_total_bytes(device, old_size); - if (device->writeable) + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) device->fs_devices->total_rw_bytes += diff; atomic64_add(diff, &fs_info->free_chunk_space); mutex_unlock(&fs_info->chunk_mutex); @@ -4678,14 +4767,15 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 max_avail; u64 dev_offset; - if (!device->writeable) { + if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { WARN(1, KERN_ERR "BTRFS: read-only device in alloc_list\n"); continue; } - if (!device->in_fs_metadata || - device->is_tgtdev_for_dev_replace) + if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, + &device->dev_state) || + test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) continue; if (device->total_bytes > device->bytes_used) @@ -5033,12 +5123,13 @@ int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset) map = em->map_lookup; for (i = 0; i < map->num_stripes; i++) { - if (map->stripes[i].dev->missing) { + if (test_bit(BTRFS_DEV_STATE_MISSING, + &map->stripes[i].dev->dev_state)) { miss_ndevs++; continue; } - - if (!map->stripes[i].dev->writeable) { + if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, + &map->stripes[i].dev->dev_state)) { readonly = 1; goto end; } @@ -5104,7 +5195,14 @@ int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len) else if (map->type & BTRFS_BLOCK_GROUP_RAID5) ret = 2; else if (map->type & BTRFS_BLOCK_GROUP_RAID6) - ret = 3; + /* + * There could be two corrupted data stripes, we need + * to loop retry in order to rebuild the correct data. + * + * Fail a stripe at a time on every retry except the + * stripe under reconstruction. + */ + ret = map->num_stripes; else ret = 1; free_extent_map(em); @@ -6004,15 +6102,14 @@ static void btrfs_end_bio(struct bio *bio) dev = bbio->stripes[stripe_index].dev; if (dev->bdev) { if (bio_op(bio) == REQ_OP_WRITE) - btrfs_dev_stat_inc(dev, + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS); else - btrfs_dev_stat_inc(dev, + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); if (bio->bi_opf & REQ_PREFLUSH) - btrfs_dev_stat_inc(dev, + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_FLUSH_ERRS); - btrfs_dev_stat_print_on_error(dev); } } } @@ -6062,16 +6159,15 @@ static noinline void btrfs_schedule_bio(struct btrfs_device *device, int should_queue = 1; struct btrfs_pending_bios *pending_bios; - if (device->missing || !device->bdev) { + if (test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) || + !device->bdev) { bio_io_error(bio); return; } /* don't bother with additional async steps for reads, right now */ if (bio_op(bio) == REQ_OP_READ) { - bio_get(bio); btrfsic_submit_bio(bio); - bio_put(bio); return; } @@ -6208,7 +6304,8 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio, for (dev_nr = 0; dev_nr < total_devs; dev_nr++) { dev = bbio->stripes[dev_nr].dev; if (!dev || !dev->bdev || - (bio_op(first_bio) == REQ_OP_WRITE && !dev->writeable)) { + (bio_op(first_bio) == REQ_OP_WRITE && + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))) { bbio_error(bbio, first_bio, logical); continue; } @@ -6257,7 +6354,7 @@ static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices, device->fs_devices = fs_devices; fs_devices->num_devices++; - device->missing = 1; + set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); fs_devices->missing_devices++; return device; @@ -6273,8 +6370,8 @@ static struct btrfs_device *add_missing_dev(struct btrfs_fs_devices *fs_devices, * is generated. * * Return: a pointer to a new &struct btrfs_device on success; ERR_PTR() - * on error. Returned struct is not linked onto any lists and can be - * destroyed with kfree() right away. + * on error. Returned struct is not linked onto any lists and must be + * destroyed with free_device. */ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, const u64 *devid, @@ -6297,8 +6394,7 @@ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, ret = find_next_devid(fs_info, &tmp); if (ret) { - bio_put(dev->flush_bio); - kfree(dev); + free_device(dev); return ERR_PTR(ret); } } @@ -6477,7 +6573,9 @@ static int read_one_chunk(struct btrfs_fs_info *fs_info, struct btrfs_key *key, } btrfs_report_missing_device(fs_info, devid, uuid, false); } - map->stripes[i].dev->in_fs_metadata = 1; + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, + &(map->stripes[i].dev->dev_state)); + } write_lock(&map_tree->map_tree.lock); @@ -6506,7 +6604,7 @@ static void fill_device_from_item(struct extent_buffer *leaf, device->io_width = btrfs_device_io_width(leaf, dev_item); device->sector_size = btrfs_device_sector_size(leaf, dev_item); WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID); - device->is_tgtdev_for_dev_replace = 0; + clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state); ptr = btrfs_device_uuid(dev_item); read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE); @@ -6618,7 +6716,8 @@ static int read_one_dev(struct btrfs_fs_info *fs_info, dev_uuid, false); } - if(!device->bdev && !device->missing) { + if (!device->bdev && + !test_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)) { /* * this happens when a device that was properly setup * in the device info lists suddenly goes bad. @@ -6626,12 +6725,13 @@ static int read_one_dev(struct btrfs_fs_info *fs_info, * device->missing to one here */ device->fs_devices->missing_devices++; - device->missing = 1; + set_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state); } /* Move the device to its own fs_devices */ if (device->fs_devices != fs_devices) { - ASSERT(device->missing); + ASSERT(test_bit(BTRFS_DEV_STATE_MISSING, + &device->dev_state)); list_move(&device->dev_list, &fs_devices->devices); device->fs_devices->num_devices--; @@ -6645,15 +6745,16 @@ static int read_one_dev(struct btrfs_fs_info *fs_info, } if (device->fs_devices != fs_info->fs_devices) { - BUG_ON(device->writeable); + BUG_ON(test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)); if (device->generation != btrfs_device_generation(leaf, dev_item)) return -EINVAL; } fill_device_from_item(leaf, dev_item, device); - device->in_fs_metadata = 1; - if (device->writeable && !device->is_tgtdev_for_dev_replace) { + set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state); + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) && + !test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) { device->fs_devices->total_rw_bytes += device->total_bytes; atomic64_add(device->total_bytes - device->bytes_used, &fs_info->free_chunk_space); @@ -6785,10 +6886,13 @@ out_short_read: /* * Check if all chunks in the fs are OK for read-write degraded mount * + * If the @failing_dev is specified, it's accounted as missing. + * * Return true if all chunks meet the minimal RW mount requirements. * Return false if any chunk doesn't meet the minimal RW mount requirements. */ -bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info) +bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info, + struct btrfs_device *failing_dev) { struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; struct extent_map *em; @@ -6816,12 +6920,16 @@ bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info) for (i = 0; i < map->num_stripes; i++) { struct btrfs_device *dev = map->stripes[i].dev; - if (!dev || !dev->bdev || dev->missing || + if (!dev || !dev->bdev || + test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) || dev->last_flush_error) missing++; + else if (failing_dev && failing_dev == dev) + missing++; } if (missing > max_tolerated) { - btrfs_warn(fs_info, + if (!failing_dev) + btrfs_warn(fs_info, "chunk %llu missing %d devices, max tolerance is %d for writeable mount", em->start, missing, max_tolerated); free_extent_map(em); @@ -7092,10 +7200,24 @@ int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { - if (!device->dev_stats_valid || !btrfs_dev_stats_dirty(device)) + stats_cnt = atomic_read(&device->dev_stats_ccnt); + if (!device->dev_stats_valid || stats_cnt == 0) continue; - stats_cnt = atomic_read(&device->dev_stats_ccnt); + + /* + * There is a LOAD-LOAD control dependency between the value of + * dev_stats_ccnt and updating the on-disk values which requires + * reading the in-memory counters. Such control dependencies + * require explicit read memory barriers. + * + * This memory barriers pairs with smp_mb__before_atomic in + * btrfs_dev_stat_inc/btrfs_dev_stat_set and with the full + * barrier implied by atomic_xchg in + * btrfs_dev_stats_read_and_reset + */ + smp_rmb(); + ret = update_dev_stat_item(trans, fs_info, device); if (!ret) atomic_sub(stats_cnt, &device->dev_stats_ccnt); |