This BUG_ON() is really just a crappy way to workaround the _must_check
attribute of submit_one_bio().
Now kill the BUG_ON() and allow flush_write_bio() to return error
number.
Also add _must_check attribute to flush_write_bio(), and modify all
callers to handle the possible error returned.
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
fs/btrfs/extent_io.c | 77 +++++++++++++++++++++++++++++++++-----------
1 file changed, 58 insertions(+), 19 deletions(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 8a2335713a2d..a60f3ec22053 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -169,15 +169,15 @@ static int __must_check submit_one_bio(struct bio *bio, int mirror_num,
return blk_status_to_errno(ret);
}
-static void flush_write_bio(struct extent_page_data *epd)
+static int __must_check flush_write_bio(struct extent_page_data *epd)
{
- if (epd->bio) {
- int ret;
+ int ret = 0;
+ if (epd->bio) {
ret = submit_one_bio(epd->bio, 0, 0);
- BUG_ON(ret < 0); /* -ENOMEM */
epd->bio = NULL;
}
+ return ret;
}
int __init extent_io_init(void)
@@ -3504,13 +3504,15 @@ lock_extent_buffer_for_io(struct extent_buffer *eb,
struct btrfs_fs_info *fs_info,
struct extent_page_data *epd)
{
- int i, num_pages;
+ int i, num_pages, failed_page_nr;
int flush = 0;
int ret = 0;
if (!btrfs_try_tree_write_lock(eb)) {
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ return ret;
flush = 1;
- flush_write_bio(epd);
btrfs_tree_lock(eb);
}
@@ -3519,7 +3521,9 @@ lock_extent_buffer_for_io(struct extent_buffer *eb,
if (!epd->sync_io)
return 0;
if (!flush) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ return ret;
flush = 1;
}
while (1) {
@@ -3560,7 +3564,11 @@ lock_extent_buffer_for_io(struct extent_buffer *eb,
if (!trylock_page(p)) {
if (!flush) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ if (ret < 0) {
+ failed_page_nr = i;
+ goto err_unlock;
+ }
flush = 1;
}
lock_page(p);
@@ -3568,6 +3576,15 @@ lock_extent_buffer_for_io(struct extent_buffer *eb,
}
return ret;
+
+err_unlock:
+ /* Unlock these already locked pages */
+ for (i = 0; i < failed_page_nr; i++) {
+ struct page *p = eb->pages[i];
+
+ unlock_page(p);
+ }
+ return ret;
}
static void end_extent_buffer_writeback(struct extent_buffer *eb)
@@ -3751,6 +3768,7 @@ int btree_write_cache_pages(struct address_space *mapping,
.sync_io = wbc->sync_mode == WB_SYNC_ALL,
};
int ret = 0;
+ int flush_ret;
int done = 0;
int nr_to_write_done = 0;
struct pagevec pvec;
@@ -3818,6 +3836,11 @@ int btree_write_cache_pages(struct address_space *mapping,
prev_eb = eb;
ret = lock_extent_buffer_for_io(eb, fs_info, &epd);
+ if (ret < 0) {
+ free_extent_buffer(eb);
+ done = 1;
+ break;
+ }
if (!ret) {
free_extent_buffer(eb);
continue;
@@ -3850,8 +3873,10 @@ int btree_write_cache_pages(struct address_space *mapping,
index = 0;
goto retry;
}
- flush_write_bio(&epd);
- return ret;
+ flush_ret = flush_write_bio(&epd);
+ if (ret)
+ return ret;
+ return flush_ret;
}
/**
@@ -3947,7 +3972,9 @@ static int extent_write_cache_pages(struct address_space *mapping,
* tmpfs file mapping
*/
if (!trylock_page(page)) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ break;
lock_page(page);
}
@@ -3957,8 +3984,11 @@ static int extent_write_cache_pages(struct address_space *mapping,
}
if (wbc->sync_mode != WB_SYNC_NONE) {
- if (PageWriteback(page))
- flush_write_bio(epd);
+ if (PageWriteback(page)) {
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ break;
+ }
wait_on_page_writeback(page);
}
@@ -4019,6 +4049,7 @@ static int extent_write_cache_pages(struct address_space *mapping,
int extent_write_full_page(struct page *page, struct writeback_control *wbc)
{
int ret;
+ int flush_ret;
struct extent_page_data epd = {
.bio = NULL,
.tree = &BTRFS_I(page->mapping->host)->io_tree,
@@ -4028,14 +4059,17 @@ int extent_write_full_page(struct page *page, struct writeback_control *wbc)
ret = __extent_writepage(page, wbc, &epd);
- flush_write_bio(&epd);
- return ret;
+ flush_ret = flush_write_bio(&epd);
+ if (ret)
+ return ret;
+ return flush_ret;
}
int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
int mode)
{
int ret = 0;
+ int flush_ret;
struct address_space *mapping = inode->i_mapping;
struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
struct page *page;
@@ -4068,14 +4102,17 @@ int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
start += PAGE_SIZE;
}
- flush_write_bio(&epd);
- return ret;
+ flush_ret = flush_write_bio(&epd);
+ if (ret)
+ return ret;
+ return flush_ret;
}
int extent_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
int ret = 0;
+ int flush_ret;
struct extent_page_data epd = {
.bio = NULL,
.tree = &BTRFS_I(mapping->host)->io_tree,
@@ -4084,8 +4121,10 @@ int extent_writepages(struct address_space *mapping,
};
ret = extent_write_cache_pages(mapping, wbc, &epd);
- flush_write_bio(&epd);
- return ret;
+ flush_ret = flush_write_bio(&epd);
+ if (ret)
+ return ret;
+ return flush_ret;
}
int extent_readpages(struct address_space *mapping, struct list_head *pages,
--
2.20.1
