From dfe25020689bb2d318782d2c9c7141203583fc70 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 13 May 2008 13:46:40 -0400 Subject: Btrfs: Add mount -o degraded to allow mounts to continue with missing devices Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 49 +++++++++++++++++++++++++++++-------------------- 1 file changed, 29 insertions(+), 20 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 574b1245964e..38b0d9ecda6a 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -614,21 +614,6 @@ int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize, return ret; } -static int close_all_devices(struct btrfs_fs_info *fs_info) -{ - struct list_head *list; - struct list_head *next; - struct btrfs_device *device; - - list = &fs_info->fs_devices->devices; - list_for_each(next, list) { - device = list_entry(next, struct btrfs_device, dev_list); - close_bdev_excl(device->bdev); - device->bdev = NULL; - } - return 0; -} - struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize) { @@ -927,6 +912,8 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits) list_for_each(cur, &info->fs_devices->devices) { device = list_entry(cur, struct btrfs_device, dev_list); + if (!device->bdev) + continue; bdi = blk_get_backing_dev_info(device->bdev); if (bdi && bdi_congested(bdi, bdi_bits)) { ret = 1; @@ -1140,7 +1127,8 @@ static void btrfs_async_submit_work(struct work_struct *work) } struct btrfs_root *open_ctree(struct super_block *sb, - struct btrfs_fs_devices *fs_devices) + struct btrfs_fs_devices *fs_devices, + char *options) { u32 sectorsize; u32 nodesize; @@ -1276,12 +1264,19 @@ struct btrfs_root *open_ctree(struct super_block *sb, if (!btrfs_super_root(disk_super)) goto fail_sb_buffer; - if (btrfs_super_num_devices(disk_super) != fs_devices->num_devices) { + btrfs_parse_options(options, tree_root, NULL); + + if (btrfs_super_num_devices(disk_super) > fs_devices->num_devices) { printk("Btrfs: wanted %llu devices, but found %llu\n", (unsigned long long)btrfs_super_num_devices(disk_super), (unsigned long long)fs_devices->num_devices); - goto fail_sb_buffer; + if (btrfs_test_opt(tree_root, DEGRADED)) + printk("continuing in degraded mode\n"); + else { + goto fail_sb_buffer; + } } + fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super); nodesize = btrfs_super_nodesize(disk_super); @@ -1329,6 +1324,8 @@ struct btrfs_root *open_ctree(struct super_block *sb, ret = btrfs_read_chunk_tree(chunk_root); BUG_ON(ret); + btrfs_close_extra_devices(fs_devices); + blocksize = btrfs_level_size(tree_root, btrfs_super_root_level(disk_super)); @@ -1374,7 +1371,7 @@ fail_sb_buffer: fail_iput: iput(fs_info->btree_inode); fail: - close_all_devices(fs_info); + btrfs_close_devices(fs_info->fs_devices); btrfs_mapping_tree_free(&fs_info->mapping_tree); kfree(extent_root); @@ -1429,6 +1426,13 @@ int write_all_supers(struct btrfs_root *root) dev_item = &sb->dev_item; list_for_each(cur, head) { dev = list_entry(cur, struct btrfs_device, dev_list); + if (!dev->bdev) { + total_errors++; + continue; + } + if (!dev->in_fs_metadata) + continue; + btrfs_set_stack_device_type(dev_item, dev->type); btrfs_set_stack_device_id(dev_item, dev->devid); btrfs_set_stack_device_total_bytes(dev_item, dev->total_bytes); @@ -1482,6 +1486,11 @@ int write_all_supers(struct btrfs_root *root) list_for_each(cur, head) { dev = list_entry(cur, struct btrfs_device, dev_list); + if (!dev->bdev) + continue; + if (!dev->in_fs_metadata) + continue; + BUG_ON(!dev->pending_io); bh = dev->pending_io; wait_on_buffer(bh); @@ -1631,7 +1640,7 @@ int close_ctree(struct btrfs_root *root) kfree(hasher); } #endif - close_all_devices(fs_info); + btrfs_close_devices(fs_info->fs_devices); btrfs_mapping_tree_free(&fs_info->mapping_tree); #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,23) -- cgit v1.2.2