diff options
Diffstat (limited to 'fs/btrfs/volumes.c')
-rw-r--r-- | fs/btrfs/volumes.c | 374 |
1 files changed, 349 insertions, 25 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 1411b99555a4..8a3d2594b807 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -23,6 +23,7 @@ #include <linux/random.h> #include <linux/iocontext.h> #include <linux/capability.h> +#include <linux/ratelimit.h> #include <linux/kthread.h> #include <asm/div64.h> #include "compat.h" @@ -34,11 +35,14 @@ #include "volumes.h" #include "async-thread.h" #include "check-integrity.h" +#include "rcu-string.h" static int init_first_rw_device(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_device *device); static int btrfs_relocate_sys_chunks(struct btrfs_root *root); +static void __btrfs_reset_dev_stats(struct btrfs_device *dev); +static void btrfs_dev_stat_print_on_load(struct btrfs_device *device); static DEFINE_MUTEX(uuid_mutex); static LIST_HEAD(fs_uuids); @@ -61,7 +65,7 @@ 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); - kfree(device->name); + rcu_string_free(device->name); kfree(device); } kfree(fs_devices); @@ -331,8 +335,8 @@ static noinline int device_list_add(const char *path, { struct btrfs_device *device; struct btrfs_fs_devices *fs_devices; + struct rcu_string *name; u64 found_transid = btrfs_super_generation(disk_super); - char *name; fs_devices = find_fsid(disk_super->fsid); if (!fs_devices) { @@ -361,15 +365,18 @@ static noinline int device_list_add(const char *path, return -ENOMEM; } device->devid = devid; + device->dev_stats_valid = 0; device->work.func = pending_bios_fn; memcpy(device->uuid, disk_super->dev_item.uuid, BTRFS_UUID_SIZE); spin_lock_init(&device->io_lock); - device->name = kstrdup(path, GFP_NOFS); - if (!device->name) { + + name = rcu_string_strdup(path, GFP_NOFS); + if (!name) { kfree(device); return -ENOMEM; } + rcu_assign_pointer(device->name, name); INIT_LIST_HEAD(&device->dev_alloc_list); /* init readahead state */ @@ -386,12 +393,12 @@ static noinline int device_list_add(const char *path, device->fs_devices = fs_devices; fs_devices->num_devices++; - } else if (!device->name || strcmp(device->name, path)) { - name = kstrdup(path, GFP_NOFS); + } else if (!device->name || strcmp(device->name->str, path)) { + name = rcu_string_strdup(path, GFP_NOFS); if (!name) return -ENOMEM; - kfree(device->name); - device->name = name; + rcu_string_free(device->name); + rcu_assign_pointer(device->name, name); if (device->missing) { fs_devices->missing_devices--; device->missing = 0; @@ -426,15 +433,22 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig) /* We have held the volume lock, it is safe to get the devices. */ list_for_each_entry(orig_dev, &orig->devices, dev_list) { + struct rcu_string *name; + device = kzalloc(sizeof(*device), GFP_NOFS); if (!device) goto error; - device->name = kstrdup(orig_dev->name, GFP_NOFS); - if (!device->name) { + /* + * This is ok to do without rcu read locked because we hold the + * uuid mutex so nothing we touch in here is going to disappear. + */ + name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS); + if (!name) { kfree(device); goto error; } + rcu_assign_pointer(device->name, name); device->devid = orig_dev->devid; device->work.func = pending_bios_fn; @@ -487,7 +501,7 @@ again: } list_del_init(&device->dev_list); fs_devices->num_devices--; - kfree(device->name); + rcu_string_free(device->name); kfree(device); } @@ -512,7 +526,7 @@ static void __free_device(struct work_struct *work) if (device->bdev) blkdev_put(device->bdev, device->mode); - kfree(device->name); + rcu_string_free(device->name); kfree(device); } @@ -536,6 +550,7 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) mutex_lock(&fs_devices->device_list_mutex); list_for_each_entry(device, &fs_devices->devices, dev_list) { struct btrfs_device *new_device; + struct rcu_string *name; if (device->bdev) fs_devices->open_devices--; @@ -551,8 +566,11 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices) new_device = kmalloc(sizeof(*new_device), GFP_NOFS); BUG_ON(!new_device); /* -ENOMEM */ memcpy(new_device, device, sizeof(*new_device)); - new_device->name = kstrdup(device->name, GFP_NOFS); - BUG_ON(device->name && !new_device->name); /* -ENOMEM */ + + /* Safe because we are under uuid_mutex */ + name = rcu_string_strdup(device->name->str, GFP_NOFS); + BUG_ON(device->name && !name); /* -ENOMEM */ + rcu_assign_pointer(new_device->name, name); new_device->bdev = NULL; new_device->writeable = 0; new_device->in_fs_metadata = 0; @@ -617,9 +635,9 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, if (!device->name) continue; - bdev = blkdev_get_by_path(device->name, flags, holder); + bdev = blkdev_get_by_path(device->name->str, flags, holder); if (IS_ERR(bdev)) { - printk(KERN_INFO "open %s failed\n", device->name); + printk(KERN_INFO "open %s failed\n", device->name->str); goto error; } filemap_write_and_wait(bdev->bd_inode->i_mapping); @@ -1628,12 +1646,13 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) struct block_device *bdev; struct list_head *devices; struct super_block *sb = root->fs_info->sb; + struct rcu_string *name; u64 total_bytes; int seeding_dev = 0; int ret = 0; if ((sb->s_flags & MS_RDONLY) && !root->fs_info->fs_devices->seeding) - return -EINVAL; + return -EROFS; bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL, root->fs_info->bdev_holder); @@ -1667,23 +1686,24 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path) goto error; } - device->name = kstrdup(device_path, GFP_NOFS); - if (!device->name) { + name = rcu_string_strdup(device_path, GFP_NOFS); + if (!name) { kfree(device); ret = -ENOMEM; goto error; } + rcu_assign_pointer(device->name, name); ret = find_next_devid(root, &device->devid); if (ret) { - kfree(device->name); + rcu_string_free(device->name); kfree(device); goto error; } trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { - kfree(device->name); + rcu_string_free(device->name); kfree(device); ret = PTR_ERR(trans); goto error; @@ -1792,7 +1812,7 @@ error_trans: unlock_chunks(root); btrfs_abort_transaction(trans, root, ret); btrfs_end_transaction(trans, root); - kfree(device->name); + rcu_string_free(device->name); kfree(device); error: blkdev_put(bdev, FMODE_EXCL); @@ -4001,13 +4021,58 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree, return 0; } +static void *merge_stripe_index_into_bio_private(void *bi_private, + unsigned int stripe_index) +{ + /* + * with single, dup, RAID0, RAID1 and RAID10, stripe_index is + * at most 1. + * The alternative solution (instead of stealing bits from the + * pointer) would be to allocate an intermediate structure + * that contains the old private pointer plus the stripe_index. + */ + BUG_ON((((uintptr_t)bi_private) & 3) != 0); + BUG_ON(stripe_index > 3); + return (void *)(((uintptr_t)bi_private) | stripe_index); +} + +static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private) +{ + return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3)); +} + +static unsigned int extract_stripe_index_from_bio_private(void *bi_private) +{ + return (unsigned int)((uintptr_t)bi_private) & 3; +} + static void btrfs_end_bio(struct bio *bio, int err) { - struct btrfs_bio *bbio = bio->bi_private; + struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private); int is_orig_bio = 0; - if (err) + if (err) { atomic_inc(&bbio->error); + if (err == -EIO || err == -EREMOTEIO) { + unsigned int stripe_index = + extract_stripe_index_from_bio_private( + bio->bi_private); + struct btrfs_device *dev; + + BUG_ON(stripe_index >= bbio->num_stripes); + dev = bbio->stripes[stripe_index].dev; + if (bio->bi_rw & WRITE) + btrfs_dev_stat_inc(dev, + BTRFS_DEV_STAT_WRITE_ERRS); + else + btrfs_dev_stat_inc(dev, + BTRFS_DEV_STAT_READ_ERRS); + if ((bio->bi_rw & WRITE_FLUSH) == WRITE_FLUSH) + btrfs_dev_stat_inc(dev, + BTRFS_DEV_STAT_FLUSH_ERRS); + btrfs_dev_stat_print_on_error(dev); + } + } if (bio == bbio->orig_bio) is_orig_bio = 1; @@ -4149,14 +4214,23 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio, bio = first_bio; } bio->bi_private = bbio; + bio->bi_private = merge_stripe_index_into_bio_private( + bio->bi_private, (unsigned int)dev_nr); bio->bi_end_io = btrfs_end_bio; bio->bi_sector = bbio->stripes[dev_nr].physical >> 9; dev = bbio->stripes[dev_nr].dev; if (dev && dev->bdev && (rw != WRITE || dev->writeable)) { +#ifdef DEBUG + struct rcu_string *name; + + rcu_read_lock(); + name = rcu_dereference(dev->name); pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu " "(%s id %llu), size=%u\n", rw, (u64)bio->bi_sector, (u_long)dev->bdev->bd_dev, - dev->name, dev->devid, bio->bi_size); + name->str, dev->devid, bio->bi_size); + rcu_read_unlock(); +#endif bio->bi_bdev = dev->bdev; if (async_submit) schedule_bio(root, dev, rw, bio); @@ -4509,6 +4583,28 @@ int btrfs_read_sys_array(struct btrfs_root *root) return ret; } +struct btrfs_device *btrfs_find_device_for_logical(struct btrfs_root *root, + u64 logical, int mirror_num) +{ + struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree; + int ret; + u64 map_length = 0; + struct btrfs_bio *bbio = NULL; + struct btrfs_device *device; + + BUG_ON(mirror_num == 0); + ret = btrfs_map_block(map_tree, WRITE, logical, &map_length, &bbio, + mirror_num); + if (ret) { + BUG_ON(bbio != NULL); + return NULL; + } + BUG_ON(mirror_num != bbio->mirror_num); + device = bbio->stripes[mirror_num - 1].dev; + kfree(bbio); + return device; +} + int btrfs_read_chunk_tree(struct btrfs_root *root) { struct btrfs_path *path; @@ -4583,3 +4679,231 @@ error: btrfs_free_path(path); return ret; } + +static void __btrfs_reset_dev_stats(struct btrfs_device *dev) +{ + int i; + + for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) + btrfs_dev_stat_reset(dev, i); +} + +int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info) +{ + struct btrfs_key key; + struct btrfs_key found_key; + struct btrfs_root *dev_root = fs_info->dev_root; + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + struct extent_buffer *eb; + int slot; + int ret = 0; + struct btrfs_device *device; + struct btrfs_path *path = NULL; + int i; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + mutex_lock(&fs_devices->device_list_mutex); + list_for_each_entry(device, &fs_devices->devices, dev_list) { + int item_size; + struct btrfs_dev_stats_item *ptr; + + key.objectid = 0; + key.type = BTRFS_DEV_STATS_KEY; + key.offset = device->devid; + ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0); + if (ret) { + printk_in_rcu(KERN_WARNING "btrfs: no dev_stats entry found for device %s (devid %llu) (OK on first mount after mkfs)\n", + rcu_str_deref(device->name), + (unsigned long long)device->devid); + __btrfs_reset_dev_stats(device); + device->dev_stats_valid = 1; + btrfs_release_path(path); + continue; + } + slot = path->slots[0]; + eb = path->nodes[0]; + btrfs_item_key_to_cpu(eb, &found_key, slot); + item_size = btrfs_item_size_nr(eb, slot); + + ptr = btrfs_item_ptr(eb, slot, + struct btrfs_dev_stats_item); + + for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { + if (item_size >= (1 + i) * sizeof(__le64)) + btrfs_dev_stat_set(device, i, + btrfs_dev_stats_value(eb, ptr, i)); + else + btrfs_dev_stat_reset(device, i); + } + + device->dev_stats_valid = 1; + btrfs_dev_stat_print_on_load(device); + btrfs_release_path(path); + } + mutex_unlock(&fs_devices->device_list_mutex); + +out: + btrfs_free_path(path); + return ret < 0 ? ret : 0; +} + +static int update_dev_stat_item(struct btrfs_trans_handle *trans, + struct btrfs_root *dev_root, + struct btrfs_device *device) +{ + struct btrfs_path *path; + struct btrfs_key key; + struct extent_buffer *eb; + struct btrfs_dev_stats_item *ptr; + int ret; + int i; + + key.objectid = 0; + key.type = BTRFS_DEV_STATS_KEY; + key.offset = device->devid; + + path = btrfs_alloc_path(); + BUG_ON(!path); + ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1); + if (ret < 0) { + printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n", + ret, rcu_str_deref(device->name)); + 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 */ + ret = btrfs_del_item(trans, dev_root, path); + if (ret != 0) { + printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n", + rcu_str_deref(device->name), 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) { + printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n", + rcu_str_deref(device->name), ret); + goto out; + } + } + + eb = path->nodes[0]; + ptr = btrfs_item_ptr(eb, path->slots[0], struct btrfs_dev_stats_item); + for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) + btrfs_set_dev_stats_value(eb, ptr, i, + btrfs_dev_stat_read(device, i)); + btrfs_mark_buffer_dirty(eb); + +out: + btrfs_free_path(path); + return ret; +} + +/* + * called from commit_transaction. Writes all changed device stats to disk. + */ +int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info) +{ + struct btrfs_root *dev_root = fs_info->dev_root; + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + struct btrfs_device *device; + int ret = 0; + + mutex_lock(&fs_devices->device_list_mutex); + list_for_each_entry(device, &fs_devices->devices, dev_list) { + if (!device->dev_stats_valid || !device->dev_stats_dirty) + continue; + + ret = update_dev_stat_item(trans, dev_root, device); + if (!ret) + device->dev_stats_dirty = 0; + } + mutex_unlock(&fs_devices->device_list_mutex); + + return ret; +} + +void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index) +{ + btrfs_dev_stat_inc(dev, index); + btrfs_dev_stat_print_on_error(dev); +} + +void btrfs_dev_stat_print_on_error(struct btrfs_device *dev) +{ + if (!dev->dev_stats_valid) + return; + printk_ratelimited_in_rcu(KERN_ERR + "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", + rcu_str_deref(dev->name), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), + btrfs_dev_stat_read(dev, + BTRFS_DEV_STAT_CORRUPTION_ERRS), + btrfs_dev_stat_read(dev, + BTRFS_DEV_STAT_GENERATION_ERRS)); +} + +static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev) +{ + printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n", + rcu_str_deref(dev->name), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS), + btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_GENERATION_ERRS)); +} + +int btrfs_get_dev_stats(struct btrfs_root *root, + struct btrfs_ioctl_get_dev_stats *stats, + int reset_after_read) +{ + struct btrfs_device *dev; + struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; + int i; + + mutex_lock(&fs_devices->device_list_mutex); + dev = btrfs_find_device(root, stats->devid, NULL, NULL); + mutex_unlock(&fs_devices->device_list_mutex); + + if (!dev) { + printk(KERN_WARNING + "btrfs: get dev_stats failed, device not found\n"); + return -ENODEV; + } else if (!dev->dev_stats_valid) { + printk(KERN_WARNING + "btrfs: get dev_stats failed, not yet valid\n"); + return -ENODEV; + } else if (reset_after_read) { + for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) { + if (stats->nr_items > i) + stats->values[i] = + btrfs_dev_stat_read_and_reset(dev, i); + else + btrfs_dev_stat_reset(dev, i); + } + } else { + for (i = 0; i < BTRFS_DEV_STAT_VALUES_MAX; i++) + if (stats->nr_items > i) + stats->values[i] = btrfs_dev_stat_read(dev, i); + } + if (stats->nr_items > BTRFS_DEV_STAT_VALUES_MAX) + stats->nr_items = BTRFS_DEV_STAT_VALUES_MAX; + return 0; +} |