ext4: reimplement ext4_find_delay_alloc_range on extent status tree
Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com>
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 67660fa..e0bedd1 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3461,115 +3461,34 @@
/**
* ext4_find_delalloc_range: find delayed allocated block in the given range.
*
- * Goes through the buffer heads in the range [lblk_start, lblk_end] and returns
- * whether there are any buffers marked for delayed allocation. It returns '1'
- * on the first delalloc'ed buffer head found. If no buffer head in the given
- * range is marked for delalloc, it returns 0.
- * lblk_start should always be <= lblk_end.
- * search_hint_reverse is to indicate that searching in reverse from lblk_end to
- * lblk_start might be more efficient (i.e., we will likely hit the delalloc'ed
- * block sooner). This is useful when blocks are truncated sequentially from
- * lblk_start towards lblk_end.
+ * Return 1 if there is a delalloc block in the range, otherwise 0.
*/
static int ext4_find_delalloc_range(struct inode *inode,
ext4_lblk_t lblk_start,
- ext4_lblk_t lblk_end,
- int search_hint_reverse)
+ ext4_lblk_t lblk_end)
{
- struct address_space *mapping = inode->i_mapping;
- struct buffer_head *head, *bh = NULL;
- struct page *page;
- ext4_lblk_t i, pg_lblk;
- pgoff_t index;
+ struct extent_status es;
- if (!test_opt(inode->i_sb, DELALLOC))
- return 0;
-
- /* reverse search wont work if fs block size is less than page size */
- if (inode->i_blkbits < PAGE_CACHE_SHIFT)
- search_hint_reverse = 0;
-
- if (search_hint_reverse)
- i = lblk_end;
+ es.start = lblk_start;
+ ext4_es_find_extent(inode, &es);
+ if (es.len == 0)
+ return 0; /* there is no delay extent in this tree */
+ else if (es.start <= lblk_start && lblk_start < es.start + es.len)
+ return 1;
+ else if (lblk_start <= es.start && es.start <= lblk_end)
+ return 1;
else
- i = lblk_start;
-
- index = i >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
-
- while ((i >= lblk_start) && (i <= lblk_end)) {
- page = find_get_page(mapping, index);
- if (!page)
- goto nextpage;
-
- if (!page_has_buffers(page))
- goto nextpage;
-
- head = page_buffers(page);
- if (!head)
- goto nextpage;
-
- bh = head;
- pg_lblk = index << (PAGE_CACHE_SHIFT -
- inode->i_blkbits);
- do {
- if (unlikely(pg_lblk < lblk_start)) {
- /*
- * This is possible when fs block size is less
- * than page size and our cluster starts/ends in
- * middle of the page. So we need to skip the
- * initial few blocks till we reach the 'lblk'
- */
- pg_lblk++;
- continue;
- }
-
- /* Check if the buffer is delayed allocated and that it
- * is not yet mapped. (when da-buffers are mapped during
- * their writeout, their da_mapped bit is set.)
- */
- if (buffer_delay(bh) && !buffer_da_mapped(bh)) {
- page_cache_release(page);
- trace_ext4_find_delalloc_range(inode,
- lblk_start, lblk_end,
- search_hint_reverse,
- 1, i);
- return 1;
- }
- if (search_hint_reverse)
- i--;
- else
- i++;
- } while ((i >= lblk_start) && (i <= lblk_end) &&
- ((bh = bh->b_this_page) != head));
-nextpage:
- if (page)
- page_cache_release(page);
- /*
- * Move to next page. 'i' will be the first lblk in the next
- * page.
- */
- if (search_hint_reverse)
- index--;
- else
- index++;
- i = index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
- }
-
- trace_ext4_find_delalloc_range(inode, lblk_start, lblk_end,
- search_hint_reverse, 0, 0);
- return 0;
+ return 0;
}
-int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk,
- int search_hint_reverse)
+int ext4_find_delalloc_cluster(struct inode *inode, ext4_lblk_t lblk)
{
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
ext4_lblk_t lblk_start, lblk_end;
lblk_start = lblk & (~(sbi->s_cluster_ratio - 1));
lblk_end = lblk_start + sbi->s_cluster_ratio - 1;
- return ext4_find_delalloc_range(inode, lblk_start, lblk_end,
- search_hint_reverse);
+ return ext4_find_delalloc_range(inode, lblk_start, lblk_end);
}
/**
@@ -3630,7 +3549,7 @@
lblk_from = lblk_start & (~(sbi->s_cluster_ratio - 1));
lblk_to = lblk_from + c_offset - 1;
- if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0))
+ if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
allocated_clusters--;
}
@@ -3640,7 +3559,7 @@
lblk_from = lblk_start + num_blks;
lblk_to = lblk_from + (sbi->s_cluster_ratio - c_offset) - 1;
- if (ext4_find_delalloc_range(inode, lblk_from, lblk_to, 0))
+ if (ext4_find_delalloc_range(inode, lblk_from, lblk_to))
allocated_clusters--;
}
@@ -3927,7 +3846,7 @@
if (ext4_ext_in_cache(inode, map->m_lblk, &newex)) {
if (!newex.ee_start_lo && !newex.ee_start_hi) {
if ((sbi->s_cluster_ratio > 1) &&
- ext4_find_delalloc_cluster(inode, map->m_lblk, 0))
+ ext4_find_delalloc_cluster(inode, map->m_lblk))
map->m_flags |= EXT4_MAP_FROM_CLUSTER;
if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
@@ -4015,7 +3934,7 @@
}
if ((sbi->s_cluster_ratio > 1) &&
- ext4_find_delalloc_cluster(inode, map->m_lblk, 0))
+ ext4_find_delalloc_cluster(inode, map->m_lblk))
map->m_flags |= EXT4_MAP_FROM_CLUSTER;
/*