ext4: Always use ext4_bio_write_page() for writeout
Currently we sometimes used block_write_full_page() and sometimes
ext4_bio_write_page() for writeback (depending on mount options and call
path). Let's always use ext4_bio_write_page() to simplify things a bit.
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 80683bf..82f9342 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -134,8 +134,6 @@
static void ext4_invalidatepage(struct page *page, unsigned long offset);
static int noalloc_get_block_write(struct inode *inode, sector_t iblock,
struct buffer_head *bh_result, int create);
-static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode);
-static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate);
static int __ext4_journalled_writepage(struct page *page, unsigned int len);
static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh);
static int ext4_discard_partial_page_buffers_no_lock(handle_t *handle,
@@ -808,11 +806,10 @@
* and the commit_write(). So doing the jbd2_journal_start at the start of
* prepare_write() is the right place.
*
- * Also, this function can nest inside ext4_writepage() ->
- * block_write_full_page(). In that case, we *know* that ext4_writepage()
- * has generated enough buffer credits to do the whole page. So we won't
- * block on the journal in that case, which is good, because the caller may
- * be PF_MEMALLOC.
+ * Also, this function can nest inside ext4_writepage(). In that case, we
+ * *know* that ext4_writepage() has generated enough buffer credits to do the
+ * whole page. So we won't block on the journal in that case, which is good,
+ * because the caller may be PF_MEMALLOC.
*
* By accident, ext4 can be reentered when a transaction is open via
* quota file writes. If we were to commit the transaction while thus
@@ -1463,18 +1460,9 @@
*/
if (unlikely(journal_data && PageChecked(page)))
err = __ext4_journalled_writepage(page, len);
- else if (test_opt(inode->i_sb, MBLK_IO_SUBMIT))
+ else
err = ext4_bio_write_page(&io_submit, page,
len, mpd->wbc);
- else if (buffer_uninit(page_bufs)) {
- ext4_set_bh_endio(page_bufs, inode);
- err = block_write_full_page_endio(page,
- noalloc_get_block_write,
- mpd->wbc, ext4_end_io_buffer_write);
- } else
- err = block_write_full_page(page,
- noalloc_get_block_write, mpd->wbc);
-
if (!err)
mpd->pages_written++;
/*
@@ -1891,16 +1879,16 @@
}
/*
- * This function is used as a standard get_block_t calback function
- * when there is no desire to allocate any blocks. It is used as a
- * callback function for block_write_begin() and block_write_full_page().
- * These functions should only try to map a single block at a time.
+ * This function is used as a standard get_block_t calback function when there
+ * is no desire to allocate any blocks. It is used as a callback function for
+ * block_write_begin(). These functions should only try to map a single block
+ * at a time.
*
* Since this function doesn't do block allocations even if the caller
* requests it by passing in create=1, it is critically important that
* any caller checks to make sure that any buffer heads are returned
* by this function are either all already mapped or marked for
- * delayed allocation before calling block_write_full_page(). Otherwise,
+ * delayed allocation before calling ext4_bio_write_page(). Otherwise,
* b_blocknr could be left unitialized, and the page write functions will
* be taken by surprise.
*/
@@ -2040,6 +2028,7 @@
unsigned int len;
struct buffer_head *page_bufs = NULL;
struct inode *inode = page->mapping->host;
+ struct ext4_io_submit io_submit;
trace_ext4_writepage(page);
size = i_size_read(inode);
@@ -2089,14 +2078,9 @@
*/
return __ext4_journalled_writepage(page, len);
- if (buffer_uninit(page_bufs)) {
- ext4_set_bh_endio(page_bufs, inode);
- ret = block_write_full_page_endio(page, noalloc_get_block_write,
- wbc, ext4_end_io_buffer_write);
- } else
- ret = block_write_full_page(page, noalloc_get_block_write,
- wbc);
-
+ memset(&io_submit, 0, sizeof(io_submit));
+ ret = ext4_bio_write_page(&io_submit, page, len, wbc);
+ ext4_io_submit(&io_submit);
return ret;
}
@@ -2858,36 +2842,10 @@
return mpage_readpages(mapping, pages, nr_pages, ext4_get_block);
}
-static void ext4_invalidatepage_free_endio(struct page *page, unsigned long offset)
-{
- struct buffer_head *head, *bh;
- unsigned int curr_off = 0;
-
- if (!page_has_buffers(page))
- return;
- head = bh = page_buffers(page);
- do {
- if (offset <= curr_off && test_clear_buffer_uninit(bh)
- && bh->b_private) {
- ext4_free_io_end(bh->b_private);
- bh->b_private = NULL;
- bh->b_end_io = NULL;
- }
- curr_off = curr_off + bh->b_size;
- bh = bh->b_this_page;
- } while (bh != head);
-}
-
static void ext4_invalidatepage(struct page *page, unsigned long offset)
{
trace_ext4_invalidatepage(page, offset);
- /*
- * free any io_end structure allocated for buffers to be discarded
- */
- if (ext4_should_dioread_nolock(page->mapping->host))
- ext4_invalidatepage_free_endio(page, offset);
-
/* No journalling happens on data buffers when this function is used */
WARN_ON(page_has_buffers(page) && buffer_jbd(page_buffers(page)));
@@ -2993,65 +2951,6 @@
ext4_add_complete_io(io_end);
}
-static void ext4_end_io_buffer_write(struct buffer_head *bh, int uptodate)
-{
- ext4_io_end_t *io_end = bh->b_private;
- struct inode *inode;
-
- if (!test_clear_buffer_uninit(bh) || !io_end)
- goto out;
-
- if (!(io_end->inode->i_sb->s_flags & MS_ACTIVE)) {
- ext4_msg(io_end->inode->i_sb, KERN_INFO,
- "sb umounted, discard end_io request for inode %lu",
- io_end->inode->i_ino);
- ext4_free_io_end(io_end);
- goto out;
- }
-
- /*
- * It may be over-defensive here to check EXT4_IO_END_UNWRITTEN now,
- * but being more careful is always safe for the future change.
- */
- inode = io_end->inode;
- ext4_set_io_unwritten_flag(inode, io_end);
- ext4_add_complete_io(io_end);
-out:
- bh->b_private = NULL;
- bh->b_end_io = NULL;
- clear_buffer_uninit(bh);
- end_buffer_async_write(bh, uptodate);
-}
-
-static int ext4_set_bh_endio(struct buffer_head *bh, struct inode *inode)
-{
- ext4_io_end_t *io_end;
- struct page *page = bh->b_page;
- loff_t offset = (sector_t)page->index << PAGE_CACHE_SHIFT;
- size_t size = bh->b_size;
-
-retry:
- io_end = ext4_init_io_end(inode, GFP_ATOMIC);
- if (!io_end) {
- pr_warn_ratelimited("%s: allocation fail\n", __func__);
- schedule();
- goto retry;
- }
- io_end->offset = offset;
- io_end->size = size;
- /*
- * We need to hold a reference to the page to make sure it
- * doesn't get evicted before ext4_end_io_work() has a chance
- * to convert the extent from written to unwritten.
- */
- io_end->page = page;
- get_page(io_end->page);
-
- bh->b_private = io_end;
- bh->b_end_io = ext4_end_io_buffer_write;
- return 0;
-}
-
/*
* For ext4 extent files, ext4 will do direct-io write to holes,
* preallocated extents, and those write extend the file, no need to