Btrfs: disallow some operations on the device replace target device
This patch adds some code to disallow operations on the device that
is used as the target for the device replace operation.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e9dc780..746cb6a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3649,7 +3649,7 @@
/* scrub.c */
int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
u64 end, struct btrfs_scrub_progress *progress,
- int readonly);
+ int readonly, int is_dev_replace);
void btrfs_scrub_pause(struct btrfs_root *root);
void btrfs_scrub_pause_super(struct btrfs_root *root);
void btrfs_scrub_continue(struct btrfs_root *root);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b4d438f..98af837 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -7468,7 +7468,8 @@
* check to make sure we can actually find a chunk with enough
* space to fit our block group in.
*/
- if (device->total_bytes > device->bytes_used + min_free) {
+ if (device->total_bytes > device->bytes_used + min_free &&
+ !device->is_tgtdev_for_dev_replace) {
ret = find_free_dev_extent(device, min_free,
&dev_offset, NULL);
if (!ret)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 26f46da..e54b5e5 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1375,6 +1375,11 @@
}
}
+ if (device->is_tgtdev_for_dev_replace) {
+ ret = -EINVAL;
+ goto out_free;
+ }
+
old_size = device->total_bytes;
if (mod < 0) {
@@ -3102,7 +3107,8 @@
return PTR_ERR(sa);
ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
- &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
+ &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
+ 0);
if (copy_to_user(arg, sa, sizeof(*sa)))
ret = -EFAULT;
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 6cf23f4..460e30b 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -116,6 +116,9 @@
u32 sectorsize;
u32 nodesize;
u32 leafsize;
+
+ int is_dev_replace;
+
/*
* statistics
*/
@@ -284,7 +287,7 @@
}
static noinline_for_stack
-struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev)
+struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
{
struct scrub_ctx *sctx;
int i;
@@ -296,6 +299,7 @@
sctx = kzalloc(sizeof(*sctx), GFP_NOFS);
if (!sctx)
goto nomem;
+ sctx->is_dev_replace = is_dev_replace;
sctx->pages_per_bio = pages_per_bio;
sctx->curr = -1;
sctx->dev_root = dev->dev_root;
@@ -2293,7 +2297,7 @@
int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
u64 end, struct btrfs_scrub_progress *progress,
- int readonly)
+ int readonly, int is_dev_replace)
{
struct scrub_ctx *sctx;
int ret;
@@ -2356,14 +2360,14 @@
mutex_lock(&fs_info->fs_devices->device_list_mutex);
dev = btrfs_find_device(fs_info, devid, NULL, NULL);
- if (!dev || dev->missing) {
+ if (!dev || (dev->missing && !is_dev_replace)) {
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
scrub_workers_put(fs_info);
return -ENODEV;
}
mutex_lock(&fs_info->scrub_lock);
- if (!dev->in_fs_metadata) {
+ if (!dev->in_fs_metadata || dev->is_tgtdev_for_dev_replace) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
scrub_workers_put(fs_info);
@@ -2376,7 +2380,7 @@
scrub_workers_put(fs_info);
return -EINPROGRESS;
}
- sctx = scrub_setup_ctx(dev);
+ sctx = scrub_setup_ctx(dev, is_dev_replace);
if (IS_ERR(sctx)) {
mutex_unlock(&fs_info->scrub_lock);
mutex_unlock(&fs_info->fs_devices->device_list_mutex);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index ef24158..837ad2d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1354,7 +1354,8 @@
min_stripe_size = BTRFS_STRIPE_LEN;
list_for_each_entry(device, &fs_devices->devices, dev_list) {
- if (!device->in_fs_metadata || !device->bdev)
+ if (!device->in_fs_metadata || !device->bdev ||
+ device->is_tgtdev_for_dev_replace)
continue;
avail_space = device->total_bytes - device->bytes_used;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 33ca36b..31f7af8 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -518,8 +518,9 @@
/* 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 (!latest_transid ||
- device->generation > latest_transid) {
+ if (!device->is_tgtdev_for_dev_replace &&
+ (!latest_transid ||
+ device->generation > latest_transid)) {
latest_devid = device->devid;
latest_transid = device->generation;
latest_bdev = device->bdev;
@@ -814,7 +815,7 @@
*length = 0;
- if (start >= device->total_bytes)
+ if (start >= device->total_bytes || device->is_tgtdev_for_dev_replace)
return 0;
path = btrfs_alloc_path();
@@ -931,7 +932,7 @@
max_hole_size = 0;
hole_size = 0;
- if (search_start >= search_end) {
+ if (search_start >= search_end || device->is_tgtdev_for_dev_replace) {
ret = -ENOSPC;
goto error;
}
@@ -1114,6 +1115,7 @@
struct btrfs_key key;
WARN_ON(!device->in_fs_metadata);
+ WARN_ON(device->is_tgtdev_for_dev_replace);
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
@@ -1375,7 +1377,9 @@
* is held.
*/
list_for_each_entry(tmp, devices, dev_list) {
- if (tmp->in_fs_metadata && !tmp->bdev) {
+ if (tmp->in_fs_metadata &&
+ !tmp->is_tgtdev_for_dev_replace &&
+ !tmp->bdev) {
device = tmp;
break;
}
@@ -1406,6 +1410,12 @@
}
}
+ if (device->is_tgtdev_for_dev_replace) {
+ pr_err("btrfs: unable to remove the dev_replace target dev\n");
+ ret = -EINVAL;
+ goto error_brelse;
+ }
+
if (device->writeable && root->fs_info->fs_devices->rw_devices == 1) {
printk(KERN_ERR "btrfs: unable to remove the only writeable "
"device\n");
@@ -1425,6 +1435,11 @@
if (ret)
goto error_undo;
+ /*
+ * TODO: the superblock still includes this device in its num_devices
+ * counter although write_all_supers() is not locked out. This
+ * could give a filesystem state which requires a degraded mount.
+ */
ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
if (ret)
goto error_undo;
@@ -1808,6 +1823,7 @@
device->dev_root = root->fs_info->dev_root;
device->bdev = bdev;
device->in_fs_metadata = 1;
+ device->is_tgtdev_for_dev_replace = 0;
device->mode = FMODE_EXCL;
set_blocksize(device->bdev, 4096);
@@ -1971,7 +1987,8 @@
if (!device->writeable)
return -EACCES;
- if (new_size <= device->total_bytes)
+ if (new_size <= device->total_bytes ||
+ device->is_tgtdev_for_dev_replace)
return -EINVAL;
btrfs_set_super_total_bytes(super_copy, old_total + diff);
@@ -2600,7 +2617,8 @@
size_to_free = div_factor(old_size, 1);
size_to_free = min(size_to_free, (u64)1 * 1024 * 1024);
if (!device->writeable ||
- device->total_bytes - device->bytes_used > size_to_free)
+ device->total_bytes - device->bytes_used > size_to_free ||
+ device->is_tgtdev_for_dev_replace)
continue;
ret = btrfs_shrink_device(device, old_size - size_to_free);
@@ -3132,6 +3150,9 @@
u64 old_size = device->total_bytes;
u64 diff = device->total_bytes - new_size;
+ if (device->is_tgtdev_for_dev_replace)
+ return -EINVAL;
+
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
@@ -3401,7 +3422,8 @@
continue;
}
- if (!device->in_fs_metadata)
+ if (!device->in_fs_metadata ||
+ device->is_tgtdev_for_dev_replace)
continue;
if (device->total_bytes > device->bytes_used)
@@ -4612,6 +4634,7 @@
device->io_align = btrfs_device_io_align(leaf, dev_item);
device->io_width = btrfs_device_io_width(leaf, dev_item);
device->sector_size = btrfs_device_sector_size(leaf, dev_item);
+ device->is_tgtdev_for_dev_replace = 0;
ptr = (unsigned long)btrfs_device_uuid(dev_item);
read_extent_buffer(leaf, device->uuid, ptr, BTRFS_UUID_SIZE);
@@ -4722,7 +4745,7 @@
fill_device_from_item(leaf, dev_item, device);
device->dev_root = root->fs_info->dev_root;
device->in_fs_metadata = 1;
- if (device->writeable) {
+ if (device->writeable && !device->is_tgtdev_for_dev_replace) {
device->fs_devices->total_rw_bytes += device->total_bytes;
spin_lock(&root->fs_info->free_chunk_lock);
root->fs_info->free_chunk_space += device->total_bytes -
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 802e2ba..8fd5a4d 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -50,6 +50,7 @@
int in_fs_metadata;
int missing;
int can_discard;
+ int is_tgtdev_for_dev_replace;
spinlock_t io_lock;