Btrfs: Pre-allocate space for data relocation
Pre-allocate space for data relocation. This can detect ENOPSC
condition caused by fragmentation of free space.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 145a468..3943526 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2546,6 +2546,50 @@
}
static noinline_for_stack
+int prealloc_file_extent_cluster(struct inode *inode,
+ struct file_extent_cluster *cluster)
+{
+ u64 alloc_hint = 0;
+ u64 start;
+ u64 end;
+ u64 offset = BTRFS_I(inode)->index_cnt;
+ u64 num_bytes;
+ int nr = 0;
+ int ret = 0;
+
+ BUG_ON(cluster->start != cluster->boundary[0]);
+ mutex_lock(&inode->i_mutex);
+
+ ret = btrfs_check_data_free_space(inode, cluster->end +
+ 1 - cluster->start);
+ if (ret)
+ goto out;
+
+ while (nr < cluster->nr) {
+ start = cluster->boundary[nr] - offset;
+ if (nr + 1 < cluster->nr)
+ end = cluster->boundary[nr + 1] - 1 - offset;
+ else
+ end = cluster->end - offset;
+
+ lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+ num_bytes = end + 1 - start;
+ ret = btrfs_prealloc_file_range(inode, 0, start,
+ num_bytes, num_bytes,
+ end + 1, &alloc_hint);
+ unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+ if (ret)
+ break;
+ nr++;
+ }
+ btrfs_free_reserved_data_space(inode, cluster->end +
+ 1 - cluster->start);
+out:
+ mutex_unlock(&inode->i_mutex);
+ return ret;
+}
+
+static noinline_for_stack
int setup_extent_mapping(struct inode *inode, u64 start, u64 end,
u64 block_start)
{
@@ -2588,7 +2632,6 @@
u64 offset = BTRFS_I(inode)->index_cnt;
unsigned long index;
unsigned long last_index;
- unsigned int dirty_page = 0;
struct page *page;
struct file_ra_state *ra;
int nr = 0;
@@ -2601,21 +2644,24 @@
if (!ra)
return -ENOMEM;
- index = (cluster->start - offset) >> PAGE_CACHE_SHIFT;
- last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT;
-
- mutex_lock(&inode->i_mutex);
-
- i_size_write(inode, cluster->end + 1 - offset);
- ret = setup_extent_mapping(inode, cluster->start - offset,
- cluster->end - offset, cluster->start);
+ ret = prealloc_file_extent_cluster(inode, cluster);
if (ret)
- goto out_unlock;
+ goto out;
file_ra_state_init(ra, inode->i_mapping);
- WARN_ON(cluster->start != cluster->boundary[0]);
+ ret = setup_extent_mapping(inode, cluster->start - offset,
+ cluster->end - offset, cluster->start);
+ if (ret)
+ goto out;
+
+ index = (cluster->start - offset) >> PAGE_CACHE_SHIFT;
+ last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT;
while (index <= last_index) {
+ ret = btrfs_delalloc_reserve_metadata(inode, PAGE_CACHE_SIZE);
+ if (ret)
+ goto out;
+
page = find_lock_page(inode->i_mapping, index);
if (!page) {
page_cache_sync_readahead(inode->i_mapping,
@@ -2623,8 +2669,10 @@
last_index + 1 - index);
page = grab_cache_page(inode->i_mapping, index);
if (!page) {
+ btrfs_delalloc_release_metadata(inode,
+ PAGE_CACHE_SIZE);
ret = -ENOMEM;
- goto out_unlock;
+ goto out;
}
}
@@ -2640,8 +2688,10 @@
if (!PageUptodate(page)) {
unlock_page(page);
page_cache_release(page);
+ btrfs_delalloc_release_metadata(inode,
+ PAGE_CACHE_SIZE);
ret = -EIO;
- goto out_unlock;
+ goto out;
}
}
@@ -2660,10 +2710,9 @@
EXTENT_BOUNDARY, GFP_NOFS);
nr++;
}
- btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
+ btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
set_page_dirty(page);
- dirty_page++;
unlock_extent(&BTRFS_I(inode)->io_tree,
page_start, page_end, GFP_NOFS);
@@ -2671,20 +2720,11 @@
page_cache_release(page);
index++;
- if (nr < cluster->nr &&
- page_end + 1 + offset == cluster->boundary[nr]) {
- balance_dirty_pages_ratelimited_nr(inode->i_mapping,
- dirty_page);
- dirty_page = 0;
- }
- }
- if (dirty_page) {
- balance_dirty_pages_ratelimited_nr(inode->i_mapping,
- dirty_page);
+ balance_dirty_pages_ratelimited(inode->i_mapping);
+ btrfs_throttle(BTRFS_I(inode)->root);
}
WARN_ON(nr != cluster->nr);
-out_unlock:
- mutex_unlock(&inode->i_mutex);
+out:
kfree(ra);
return ret;
}