summaryrefslogtreecommitdiff
path: root/fs/btrfs/dev-replace.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs/dev-replace.c')
-rw-r--r--fs/btrfs/dev-replace.c130
1 files changed, 70 insertions, 60 deletions
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index cbb7dbfb3fff..8c8b48971bc7 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -202,13 +202,13 @@ int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
struct btrfs_dev_replace_item *ptr;
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 0);
if (!dev_replace->is_valid ||
!dev_replace->item_needs_writeback) {
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 0);
return 0;
}
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 0);
key.objectid = 0;
key.type = BTRFS_DEV_REPLACE_KEY;
@@ -264,7 +264,7 @@ int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
ptr = btrfs_item_ptr(eb, path->slots[0],
struct btrfs_dev_replace_item);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
if (dev_replace->srcdev)
btrfs_set_dev_replace_src_devid(eb, ptr,
dev_replace->srcdev->devid);
@@ -287,7 +287,7 @@ int btrfs_run_dev_replace(struct btrfs_trans_handle *trans,
btrfs_set_dev_replace_cursor_right(eb, ptr,
dev_replace->cursor_right);
dev_replace->item_needs_writeback = 0;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
btrfs_mark_buffer_dirty(eb);
@@ -356,7 +356,7 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
return PTR_ERR(trans);
}
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
switch (dev_replace->replace_state) {
case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
@@ -395,7 +395,7 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
dev_replace->is_valid = 1;
dev_replace->item_needs_writeback = 1;
args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device);
if (ret)
@@ -407,7 +407,7 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
goto leave;
}
@@ -433,7 +433,7 @@ int btrfs_dev_replace_start(struct btrfs_root *root,
leave:
dev_replace->srcdev = NULL;
dev_replace->tgtdev = NULL;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
btrfs_destroy_dev_replace_tgtdev(fs_info, tgt_device);
return ret;
}
@@ -471,18 +471,18 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
/* don't allow cancel or unmount to disturb the finishing procedure */
mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 0);
/* was the operation canceled, or is it finished? */
if (dev_replace->replace_state !=
BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED) {
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 0);
mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
return 0;
}
tgt_device = dev_replace->tgtdev;
src_device = dev_replace->srcdev;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 0);
/*
* flush all outstanding I/O and inode extent mappings before the
@@ -507,7 +507,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
/* keep away write_all_supers() during the finishing procedure */
mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
mutex_lock(&root->fs_info->chunk_mutex);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
dev_replace->replace_state =
scrub_ret ? BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED
: BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED;
@@ -528,7 +528,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
rcu_str_deref(src_device->name),
src_device->devid,
rcu_str_deref(tgt_device->name), scrub_ret);
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
mutex_unlock(&root->fs_info->chunk_mutex);
mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
mutex_unlock(&uuid_mutex);
@@ -565,7 +565,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info *fs_info,
list_add(&tgt_device->dev_alloc_list, &fs_info->fs_devices->alloc_list);
fs_info->fs_devices->rw_devices++;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
btrfs_rm_dev_replace_blocked(fs_info);
@@ -649,7 +649,7 @@ void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
struct btrfs_device *srcdev;
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 0);
/* even if !dev_replace_is_valid, the values are good enough for
* the replace_status ioctl */
args->result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_ERROR;
@@ -675,7 +675,7 @@ void btrfs_dev_replace_status(struct btrfs_fs_info *fs_info,
div_u64(btrfs_device_get_total_bytes(srcdev), 1000));
break;
}
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 0);
}
int btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info,
@@ -698,13 +698,13 @@ static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
return -EROFS;
mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
switch (dev_replace->replace_state) {
case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
result = BTRFS_IOCTL_DEV_REPLACE_RESULT_NOT_STARTED;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
goto leave;
case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
@@ -717,7 +717,7 @@ static u64 __btrfs_dev_replace_cancel(struct btrfs_fs_info *fs_info)
dev_replace->replace_state = BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED;
dev_replace->time_stopped = get_seconds();
dev_replace->item_needs_writeback = 1;
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
btrfs_scrub_cancel(fs_info);
trans = btrfs_start_transaction(root, 0);
@@ -740,7 +740,7 @@ void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
mutex_lock(&dev_replace->lock_finishing_cancel_unmount);
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
switch (dev_replace->replace_state) {
case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
@@ -756,7 +756,7 @@ void btrfs_dev_replace_suspend_for_unmount(struct btrfs_fs_info *fs_info)
break;
}
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
}
@@ -766,12 +766,12 @@ int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
struct task_struct *task;
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
- btrfs_dev_replace_lock(dev_replace);
+ btrfs_dev_replace_lock(dev_replace, 1);
switch (dev_replace->replace_state) {
case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_FINISHED:
case BTRFS_IOCTL_DEV_REPLACE_STATE_CANCELED:
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
return 0;
case BTRFS_IOCTL_DEV_REPLACE_STATE_STARTED:
break;
@@ -784,10 +784,10 @@ int btrfs_resume_dev_replace_async(struct btrfs_fs_info *fs_info)
btrfs_info(fs_info, "cannot continue dev_replace, tgtdev is missing");
btrfs_info(fs_info,
"you may cancel the operation after 'mount -o degraded'");
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
return 0;
}
- btrfs_dev_replace_unlock(dev_replace);
+ btrfs_dev_replace_unlock(dev_replace, 1);
WARN_ON(atomic_xchg(
&fs_info->mutually_exclusive_operation_running, 1));
@@ -865,48 +865,58 @@ int btrfs_dev_replace_is_ongoing(struct btrfs_dev_replace *dev_replace)
return 1;
}
-void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace)
+void btrfs_dev_replace_lock(struct btrfs_dev_replace *dev_replace, int rw)
{
- /* the beginning is just an optimization for the typical case */
- if (atomic_read(&dev_replace->nesting_level) == 0) {
-acquire_lock:
- /* this is not a nested case where the same thread
- * is trying to acqurire the same lock twice */
- mutex_lock(&dev_replace->lock);
- mutex_lock(&dev_replace->lock_management_lock);
- dev_replace->lock_owner = current->pid;
- atomic_inc(&dev_replace->nesting_level);
- mutex_unlock(&dev_replace->lock_management_lock);
- return;
+ if (rw == 1) {
+ /* write */
+again:
+ wait_event(dev_replace->read_lock_wq,
+ atomic_read(&dev_replace->blocking_readers) == 0);
+ write_lock(&dev_replace->lock);
+ if (atomic_read(&dev_replace->blocking_readers)) {
+ write_unlock(&dev_replace->lock);
+ goto again;
+ }
+ } else {
+ read_lock(&dev_replace->lock);
+ atomic_inc(&dev_replace->read_locks);
}
+}
- mutex_lock(&dev_replace->lock_management_lock);
- if (atomic_read(&dev_replace->nesting_level) > 0 &&
- dev_replace->lock_owner == current->pid) {
- WARN_ON(!mutex_is_locked(&dev_replace->lock));
- atomic_inc(&dev_replace->nesting_level);
- mutex_unlock(&dev_replace->lock_management_lock);
- return;
+void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace, int rw)
+{
+ if (rw == 1) {
+ /* write */
+ ASSERT(atomic_read(&dev_replace->blocking_readers) == 0);
+ write_unlock(&dev_replace->lock);
+ } else {
+ ASSERT(atomic_read(&dev_replace->read_locks) > 0);
+ atomic_dec(&dev_replace->read_locks);
+ read_unlock(&dev_replace->lock);
}
+}
- mutex_unlock(&dev_replace->lock_management_lock);
- goto acquire_lock;
+/* inc blocking cnt and release read lock */
+void btrfs_dev_replace_set_lock_blocking(
+ struct btrfs_dev_replace *dev_replace)
+{
+ /* only set blocking for read lock */
+ ASSERT(atomic_read(&dev_replace->read_locks) > 0);
+ atomic_inc(&dev_replace->blocking_readers);
+ read_unlock(&dev_replace->lock);
}
-void btrfs_dev_replace_unlock(struct btrfs_dev_replace *dev_replace)
+/* acquire read lock and dec blocking cnt */
+void btrfs_dev_replace_clear_lock_blocking(
+ struct btrfs_dev_replace *dev_replace)
{
- WARN_ON(!mutex_is_locked(&dev_replace->lock));
- mutex_lock(&dev_replace->lock_management_lock);
- WARN_ON(atomic_read(&dev_replace->nesting_level) < 1);
- WARN_ON(dev_replace->lock_owner != current->pid);
- atomic_dec(&dev_replace->nesting_level);
- if (atomic_read(&dev_replace->nesting_level) == 0) {
- dev_replace->lock_owner = 0;
- mutex_unlock(&dev_replace->lock_management_lock);
- mutex_unlock(&dev_replace->lock);
- } else {
- mutex_unlock(&dev_replace->lock_management_lock);
- }
+ /* only set blocking for read lock */
+ ASSERT(atomic_read(&dev_replace->read_locks) > 0);
+ ASSERT(atomic_read(&dev_replace->blocking_readers) > 0);
+ read_lock(&dev_replace->lock);
+ if (atomic_dec_and_test(&dev_replace->blocking_readers) &&
+ waitqueue_active(&dev_replace->read_lock_wq))
+ wake_up(&dev_replace->read_lock_wq);
}
void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info)