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authorChris Mason <chris.mason@oracle.com>2008-05-13 13:46:40 -0400
committerChris Mason <chris.mason@oracle.com>2008-09-25 11:04:03 -0400
commitdfe25020689bb2d318782d2c9c7141203583fc70 (patch)
treee106059546d7755af0d3b86bf47c113ca8927d7d /fs/btrfs/volumes.c
parent1259ab75c62462b8ffad90067b5e1f6312786a18 (diff)
downloadop-kernel-dev-dfe25020689bb2d318782d2c9c7141203583fc70.zip
op-kernel-dev-dfe25020689bb2d318782d2c9c7141203583fc70.tar.gz
Btrfs: Add mount -o degraded to allow mounts to continue with missing devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/volumes.c')
-rw-r--r--fs/btrfs/volumes.c279
1 files changed, 201 insertions, 78 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 5fc7fb4..43f74d1 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -73,6 +73,7 @@ int btrfs_cleanup_fs_uuids(void)
close_bdev_excl(dev->bdev);
}
list_del(&dev->dev_list);
+ kfree(dev->name);
kfree(dev);
}
}
@@ -127,7 +128,6 @@ static int device_list_add(const char *path,
memcpy(fs_devices->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
fs_devices->latest_devid = devid;
fs_devices->latest_trans = found_transid;
- fs_devices->lowest_devid = (u64)-1;
fs_devices->num_devices = 0;
device = NULL;
} else {
@@ -159,13 +159,35 @@ static int device_list_add(const char *path,
fs_devices->latest_devid = devid;
fs_devices->latest_trans = found_transid;
}
- if (fs_devices->lowest_devid > devid) {
- fs_devices->lowest_devid = devid;
- }
*fs_devices_ret = fs_devices;
return 0;
}
+int btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
+{
+ struct list_head *head = &fs_devices->devices;
+ struct list_head *cur;
+ struct btrfs_device *device;
+
+ mutex_lock(&uuid_mutex);
+again:
+ list_for_each(cur, head) {
+ device = list_entry(cur, struct btrfs_device, dev_list);
+ if (!device->in_fs_metadata) {
+printk("getting rid of extra dev %s\n", device->name);
+ if (device->bdev)
+ close_bdev_excl(device->bdev);
+ list_del(&device->dev_list);
+ list_del(&device->dev_alloc_list);
+ fs_devices->num_devices--;
+ kfree(device->name);
+ kfree(device);
+ goto again;
+ }
+ }
+ mutex_unlock(&uuid_mutex);
+ return 0;
+}
int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
{
struct list_head *head = &fs_devices->devices;
@@ -179,6 +201,7 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
close_bdev_excl(device->bdev);
}
device->bdev = NULL;
+ device->in_fs_metadata = 0;
}
mutex_unlock(&uuid_mutex);
return 0;
@@ -199,6 +222,9 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
if (device->bdev)
continue;
+ if (!device->name)
+ continue;
+
bdev = open_bdev_excl(device->name, flags, holder);
if (IS_ERR(bdev)) {
@@ -209,10 +235,8 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
set_blocksize(bdev, 4096);
if (device->devid == fs_devices->latest_devid)
fs_devices->latest_bdev = bdev;
- if (device->devid == fs_devices->lowest_devid) {
- fs_devices->lowest_bdev = bdev;
- }
device->bdev = bdev;
+ device->in_fs_metadata = 0;
}
mutex_unlock(&uuid_mutex);
@@ -439,7 +463,8 @@ int btrfs_free_dev_extent(struct btrfs_trans_handle *trans,
}
BUG_ON(ret);
- device->bytes_used -= btrfs_dev_extent_length(leaf, extent);
+ if (device->bytes_used > 0)
+ device->bytes_used -= btrfs_dev_extent_length(leaf, extent);
ret = btrfs_del_item(trans, root, path);
BUG_ON(ret);
@@ -460,6 +485,7 @@ int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans,
struct extent_buffer *leaf;
struct btrfs_key key;
+ WARN_ON(!device->in_fs_metadata);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
@@ -674,8 +700,6 @@ static int btrfs_rm_dev_item(struct btrfs_root *root,
next_dev = list_entry(fs_devices->devices.next, struct btrfs_device,
dev_list);
- if (bdev == fs_devices->lowest_bdev)
- fs_devices->lowest_bdev = next_dev->bdev;
if (bdev == root->fs_info->sb->s_bdev)
root->fs_info->sb->s_bdev = next_dev->bdev;
if (bdev == fs_devices->latest_bdev)
@@ -698,7 +722,7 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
{
struct btrfs_device *device;
struct block_device *bdev;
- struct buffer_head *bh;
+ struct buffer_head *bh = NULL;
struct btrfs_super_block *disk_super;
u64 all_avail;
u64 devid;
@@ -712,47 +736,73 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
root->fs_info->avail_metadata_alloc_bits;
if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
- root->fs_info->fs_devices->num_devices <= 4) {
+ btrfs_super_num_devices(&root->fs_info->super_copy) <= 4) {
printk("btrfs: unable to go below four devices on raid10\n");
ret = -EINVAL;
goto out;
}
if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
- root->fs_info->fs_devices->num_devices <= 2) {
+ btrfs_super_num_devices(&root->fs_info->super_copy) <= 2) {
printk("btrfs: unable to go below two devices on raid1\n");
ret = -EINVAL;
goto out;
}
- bdev = open_bdev_excl(device_path, 0, root->fs_info->bdev_holder);
- if (IS_ERR(bdev)) {
- ret = PTR_ERR(bdev);
- goto out;
- }
+ if (strcmp(device_path, "missing") == 0) {
+ struct list_head *cur;
+ struct list_head *devices;
+ struct btrfs_device *tmp;
- bh = __bread(bdev, BTRFS_SUPER_INFO_OFFSET / 4096, 4096);
- if (!bh) {
- ret = -EIO;
- goto error_close;
- }
- disk_super = (struct btrfs_super_block *)bh->b_data;
- if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
- sizeof(disk_super->magic))) {
- ret = -ENOENT;
- goto error_brelse;
- }
- if (memcmp(disk_super->fsid, root->fs_info->fsid, BTRFS_FSID_SIZE)) {
- ret = -ENOENT;
- goto error_brelse;
- }
- devid = le64_to_cpu(disk_super->dev_item.devid);
- device = btrfs_find_device(root, devid, NULL);
- if (!device) {
- ret = -ENOENT;
- goto error_brelse;
- }
+ device = NULL;
+ devices = &root->fs_info->fs_devices->devices;
+ list_for_each(cur, devices) {
+ tmp = list_entry(cur, struct btrfs_device, dev_list);
+ if (tmp->in_fs_metadata && !tmp->bdev) {
+ device = tmp;
+ break;
+ }
+ }
+ bdev = NULL;
+ bh = NULL;
+ disk_super = NULL;
+ if (!device) {
+ printk("btrfs: no missing devices found to remove\n");
+ goto out;
+ }
+
+ } else {
+ bdev = open_bdev_excl(device_path, 0,
+ root->fs_info->bdev_holder);
+ if (IS_ERR(bdev)) {
+ ret = PTR_ERR(bdev);
+ goto out;
+ }
+
+ bh = __bread(bdev, BTRFS_SUPER_INFO_OFFSET / 4096, 4096);
+ if (!bh) {
+ ret = -EIO;
+ goto error_close;
+ }
+ disk_super = (struct btrfs_super_block *)bh->b_data;
+ if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
+ sizeof(disk_super->magic))) {
+ ret = -ENOENT;
+ goto error_brelse;
+ }
+ if (memcmp(disk_super->fsid, root->fs_info->fsid,
+ BTRFS_FSID_SIZE)) {
+ ret = -ENOENT;
+ goto error_brelse;
+ }
+ devid = le64_to_cpu(disk_super->dev_item.devid);
+ device = btrfs_find_device(root, devid, NULL);
+ if (!device) {
+ ret = -ENOENT;
+ goto error_brelse;
+ }
+ }
root->fs_info->fs_devices->num_devices--;
ret = btrfs_shrink_device(device, 0);
@@ -764,19 +814,25 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
if (ret)
goto error_brelse;
- /* make sure this device isn't detected as part of the FS anymore */
- memset(&disk_super->magic, 0, sizeof(disk_super->magic));
- set_buffer_dirty(bh);
- sync_dirty_buffer(bh);
-
- brelse(bh);
-
- /* one close for the device struct or super_block */
- close_bdev_excl(device->bdev);
+ if (bh) {
+ /* make sure this device isn't detected as part of
+ * the FS anymore
+ */
+ memset(&disk_super->magic, 0, sizeof(disk_super->magic));
+ set_buffer_dirty(bh);
+ sync_dirty_buffer(bh);
- /* one close for us */
- close_bdev_excl(device->bdev);
+ brelse(bh);
+ }
+ if (device->bdev) {
+ /* one close for the device struct or super_block */
+ close_bdev_excl(device->bdev);
+ }
+ if (bdev) {
+ /* one close for us */
+ close_bdev_excl(bdev);
+ }
kfree(device->name);
kfree(device);
ret = 0;
@@ -785,7 +841,8 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
error_brelse:
brelse(bh);
error_close:
- close_bdev_excl(bdev);
+ if (bdev)
+ close_bdev_excl(bdev);
out:
mutex_unlock(&uuid_mutex);
mutex_unlock(&root->fs_info->fs_mutex);
@@ -839,6 +896,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
device->total_bytes = i_size_read(bdev->bd_inode);
device->dev_root = root->fs_info->dev_root;
device->bdev = bdev;
+ device->in_fs_metadata = 1;
ret = btrfs_add_device(trans, root, device);
if (ret)
@@ -1041,8 +1099,10 @@ int btrfs_relocate_chunk(struct btrfs_root *root,
map->stripes[i].physical);
BUG_ON(ret);
- ret = btrfs_update_device(trans, map->stripes[i].dev);
- BUG_ON(ret);
+ if (map->stripes[i].dev) {
+ ret = btrfs_update_device(trans, map->stripes[i].dev);
+ BUG_ON(ret);
+ }
}
ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid,
chunk_offset);
@@ -1415,10 +1475,13 @@ again:
while(index < num_stripes) {
device = list_entry(cur, struct btrfs_device, dev_alloc_list);
- avail = device->total_bytes - device->bytes_used;
+ if (device->total_bytes > device->bytes_used)
+ avail = device->total_bytes - device->bytes_used;
+ else
+ avail = 0;
cur = cur->next;
- if (avail >= min_free) {
+ if (device->in_fs_metadata && avail >= min_free) {
u64 ignored_start = 0;
ret = find_free_dev_extent(trans, device, path,
min_free,
@@ -1430,7 +1493,7 @@ again:
if (type & BTRFS_BLOCK_GROUP_DUP)
index++;
}
- } else if (avail > max_avail)
+ } else if (device->in_fs_metadata && avail > max_avail)
max_avail = avail;
if (cur == dev_list)
break;
@@ -1610,6 +1673,22 @@ int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
return ret;
}
+static int find_live_mirror(struct map_lookup *map, int first, int num,
+ int optimal)
+{
+ int i;
+ if (map->stripes[optimal].dev->bdev)
+ return optimal;
+ for (i = first; i < first + num; i++) {
+ if (map->stripes[i].dev->bdev)
+ return i;
+ }
+ /* we couldn't find one that doesn't fail. Just return something
+ * and the io error handling code will clean up eventually
+ */
+ return optimal;
+}
+
static int __btrfs_map_block(struct btrfs_mapping_tree *map_tree, int rw,
u64 logical, u64 *length,
struct btrfs_multi_bio **multi_ret,
@@ -1712,8 +1791,11 @@ again:
num_stripes = map->num_stripes;
else if (mirror_num)
stripe_index = mirror_num - 1;
- else
- stripe_index = current->pid % map->num_stripes;
+ else {
+ stripe_index = find_live_mirror(map, 0,
+ map->num_stripes,
+ current->pid % map->num_stripes);
+ }
} else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
if (rw & (1 << BIO_RW))
@@ -1731,8 +1813,11 @@ again:
num_stripes = map->sub_stripes;
else if (mirror_num)
stripe_index += mirror_num - 1;
- else
- stripe_index += current->pid % map->sub_stripes;
+ else {
+ stripe_index = find_live_mirror(map, stripe_index,
+ map->sub_stripes, stripe_index +
+ current->pid % map->sub_stripes);
+ }
} else {
/*
* after this do_div call, stripe_nr is the number of stripes
@@ -1749,9 +1834,11 @@ again:
struct backing_dev_info *bdi;
device = map->stripes[stripe_index].dev;
- bdi = blk_get_backing_dev_info(device->bdev);
- if (bdi->unplug_io_fn) {
- bdi->unplug_io_fn(bdi, unplug_page);
+ if (device->bdev) {
+ bdi = blk_get_backing_dev_info(device->bdev);
+ if (bdi->unplug_io_fn) {
+ bdi->unplug_io_fn(bdi, unplug_page);
+ }
}
} else {
multi->stripes[i].physical =
@@ -1880,12 +1967,21 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
}
bio->bi_sector = multi->stripes[dev_nr].physical >> 9;
dev = multi->stripes[dev_nr].dev;
-
- bio->bi_bdev = dev->bdev;
- spin_lock(&dev->io_lock);
- dev->total_ios++;
- spin_unlock(&dev->io_lock);
- submit_bio(rw, bio);
+ if (dev && dev->bdev) {
+ bio->bi_bdev = dev->bdev;
+ spin_lock(&dev->io_lock);
+ dev->total_ios++;
+ spin_unlock(&dev->io_lock);
+ submit_bio(rw, bio);
+ } else {
+ bio->bi_bdev = root->fs_info->fs_devices->latest_bdev;
+ bio->bi_sector = logical >> 9;
+#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,23)
+ bio_endio(bio, bio->bi_size, -EIO);
+#else
+ bio_endio(bio, -EIO);
+#endif
+ }
dev_nr++;
}
if (total_devs == 1)
@@ -1901,6 +1997,27 @@ struct btrfs_device *btrfs_find_device(struct btrfs_root *root, u64 devid,
return __find_device(head, devid, uuid);
}
+static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
+ u64 devid, u8 *dev_uuid)
+{
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
+
+ device = kzalloc(sizeof(*device), GFP_NOFS);
+ list_add(&device->dev_list,
+ &fs_devices->devices);
+ list_add(&device->dev_alloc_list,
+ &fs_devices->alloc_list);
+ device->barriers = 1;
+ device->dev_root = root->fs_info->dev_root;
+ device->devid = devid;
+ fs_devices->num_devices++;
+ spin_lock_init(&device->io_lock);
+ memcpy(device->uuid, dev_uuid, BTRFS_UUID_SIZE);
+ return device;
+}
+
+
static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
struct extent_buffer *leaf,
struct btrfs_chunk *chunk)
@@ -1965,11 +2082,22 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
btrfs_stripe_dev_uuid_nr(chunk, i),
BTRFS_UUID_SIZE);
map->stripes[i].dev = btrfs_find_device(root, devid, uuid);
- if (!map->stripes[i].dev) {
+
+ if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
kfree(map);
free_extent_map(em);
return -EIO;
}
+ if (!map->stripes[i].dev) {
+ map->stripes[i].dev =
+ add_missing_dev(root, devid, uuid);
+ if (!map->stripes[i].dev) {
+ kfree(map);
+ free_extent_map(em);
+ return -EIO;
+ }
+ }
+ map->stripes[i].dev->in_fs_metadata = 1;
}
spin_lock(&map_tree->map_tree.lock);
@@ -2016,20 +2144,15 @@ static int read_one_dev(struct btrfs_root *root,
BTRFS_UUID_SIZE);
device = btrfs_find_device(root, devid, dev_uuid);
if (!device) {
- printk("warning devid %Lu not found already\n", devid);
- device = kzalloc(sizeof(*device), GFP_NOFS);
+ printk("warning devid %Lu missing\n", devid);
+ device = add_missing_dev(root, devid, dev_uuid);
if (!device)
return -ENOMEM;
- list_add(&device->dev_list,
- &root->fs_info->fs_devices->devices);
- list_add(&device->dev_alloc_list,
- &root->fs_info->fs_devices->alloc_list);
- device->barriers = 1;
- spin_lock_init(&device->io_lock);
}
fill_device_from_item(leaf, dev_item, device);
device->dev_root = root->fs_info->dev_root;
+ device->in_fs_metadata = 1;
ret = 0;
#if 0
ret = btrfs_open_device(device);
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