nilfs2: fix missed-sync issue for do_sync_mapping_range()
Chris Mason pointed out that there is a missed sync issue in
nilfs_writepages():
On Wed, 17 Dec 2008 21:52:55 -0500, Chris Mason wrote:
> It looks like nilfs_writepage ignores WB_SYNC_NONE, which is used by
> do_sync_mapping_range().
where WB_SYNC_NONE in do_sync_mapping_range() was replaced with
WB_SYNC_ALL by Nick's patch (commit:
ee53a891f47444c53318b98dac947ede963db400).
This fixes the problem by letting nilfs_writepages() write out the log of
file data within the range if sync_mode is WB_SYNC_ALL.
This involves removal of nilfs_file_aio_write() which was previously
needed to ensure O_SYNC sync writes.
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index 2c4c088..ad65a73 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -654,29 +654,41 @@
.write_node_binfo = NULL,
};
-static int nilfs_lookup_dirty_data_buffers(struct inode *inode,
- struct list_head *listp,
- struct nilfs_sc_info *sci)
+static size_t nilfs_lookup_dirty_data_buffers(struct inode *inode,
+ struct list_head *listp,
+ size_t nlimit,
+ loff_t start, loff_t end)
{
- struct nilfs_segment_buffer *segbuf = sci->sc_curseg;
struct address_space *mapping = inode->i_mapping;
struct pagevec pvec;
- unsigned i, ndirties = 0, nlimit;
- pgoff_t index = 0;
- int err = 0;
+ pgoff_t index = 0, last = ULONG_MAX;
+ size_t ndirties = 0;
+ int i;
- nlimit = sci->sc_segbuf_nblocks -
- (sci->sc_nblk_this_inc + segbuf->sb_sum.nblocks);
+ if (unlikely(start != 0 || end != LLONG_MAX)) {
+ /*
+ * A valid range is given for sync-ing data pages. The
+ * range is rounded to per-page; extra dirty buffers
+ * may be included if blocksize < pagesize.
+ */
+ index = start >> PAGE_SHIFT;
+ last = end >> PAGE_SHIFT;
+ }
pagevec_init(&pvec, 0);
repeat:
- if (!pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
- PAGEVEC_SIZE))
- return 0;
+ if (unlikely(index > last) ||
+ !pagevec_lookup_tag(&pvec, mapping, &index, PAGECACHE_TAG_DIRTY,
+ min_t(pgoff_t, last - index,
+ PAGEVEC_SIZE - 1) + 1))
+ return ndirties;
for (i = 0; i < pagevec_count(&pvec); i++) {
struct buffer_head *bh, *head;
struct page *page = pvec.pages[i];
+ if (unlikely(page->index > last))
+ break;
+
if (mapping->host) {
lock_page(page);
if (!page_has_buffers(page))
@@ -687,24 +699,21 @@
bh = head = page_buffers(page);
do {
- if (buffer_dirty(bh)) {
- if (ndirties > nlimit) {
- err = -E2BIG;
- break;
- }
- get_bh(bh);
- list_add_tail(&bh->b_assoc_buffers, listp);
- ndirties++;
+ if (!buffer_dirty(bh))
+ continue;
+ get_bh(bh);
+ list_add_tail(&bh->b_assoc_buffers, listp);
+ ndirties++;
+ if (unlikely(ndirties >= nlimit)) {
+ pagevec_release(&pvec);
+ cond_resched();
+ return ndirties;
}
- bh = bh->b_this_page;
- } while (bh != head);
+ } while (bh = bh->b_this_page, bh != head);
}
pagevec_release(&pvec);
cond_resched();
-
- if (!err)
- goto repeat;
- return err;
+ goto repeat;
}
static void nilfs_lookup_dirty_node_buffers(struct inode *inode,
@@ -1058,23 +1067,31 @@
return err;
}
+static size_t nilfs_segctor_buffer_rest(struct nilfs_sc_info *sci)
+{
+ /* Remaining number of blocks within segment buffer */
+ return sci->sc_segbuf_nblocks -
+ (sci->sc_nblk_this_inc + sci->sc_curseg->sb_sum.nblocks);
+}
+
static int nilfs_segctor_scan_file(struct nilfs_sc_info *sci,
struct inode *inode,
struct nilfs_sc_operations *sc_ops)
{
LIST_HEAD(data_buffers);
LIST_HEAD(node_buffers);
- int err, err2;
+ int err;
if (!(sci->sc_stage.flags & NILFS_CF_NODE)) {
- err = nilfs_lookup_dirty_data_buffers(inode, &data_buffers,
- sci);
- if (err) {
- err2 = nilfs_segctor_apply_buffers(
+ size_t n, rest = nilfs_segctor_buffer_rest(sci);
+
+ n = nilfs_lookup_dirty_data_buffers(
+ inode, &data_buffers, rest + 1, 0, LLONG_MAX);
+ if (n > rest) {
+ err = nilfs_segctor_apply_buffers(
sci, inode, &data_buffers,
- err == -E2BIG ? sc_ops->collect_data : NULL);
- if (err == -E2BIG)
- err = err2;
+ sc_ops->collect_data);
+ BUG_ON(!err); /* always receive -E2BIG or true error */
goto break_or_fail;
}
}
@@ -1114,16 +1131,20 @@
struct inode *inode)
{
LIST_HEAD(data_buffers);
- int err, err2;
+ size_t n, rest = nilfs_segctor_buffer_rest(sci);
+ int err;
- err = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, sci);
- err2 = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
- (!err || err == -E2BIG) ?
- nilfs_collect_file_data : NULL);
- if (err == -E2BIG)
- err = err2;
- if (!err)
+ n = nilfs_lookup_dirty_data_buffers(inode, &data_buffers, rest + 1,
+ sci->sc_dsync_start,
+ sci->sc_dsync_end);
+
+ err = nilfs_segctor_apply_buffers(sci, inode, &data_buffers,
+ nilfs_collect_file_data);
+ if (!err) {
nilfs_segctor_end_finfo(sci, inode);
+ BUG_ON(n > rest);
+ /* always receive -E2BIG or true error if n > rest */
+ }
return err;
}
@@ -1276,14 +1297,13 @@
case NILFS_ST_DSYNC:
dsync_mode:
sci->sc_curseg->sb_sum.flags |= NILFS_SS_SYNDT;
- ii = sci->sc_stage.dirty_file_ptr;
+ ii = sci->sc_dsync_inode;
if (!test_bit(NILFS_I_BUSY, &ii->i_state))
break;
err = nilfs_segctor_scan_file_dsync(sci, &ii->vfs_inode);
if (unlikely(err))
break;
- sci->sc_stage.dirty_file_ptr = NULL;
sci->sc_curseg->sb_sum.flags |= NILFS_SS_LOGEND;
sci->sc_stage.scnt = NILFS_ST_DONE;
return 0;
@@ -2624,7 +2644,9 @@
/**
* nilfs_construct_dsync_segment - construct a data-only logical segment
* @sb: super block
- * @inode: the inode whose data blocks should be written out
+ * @inode: inode whose data blocks should be written out
+ * @start: start byte offset
+ * @end: end byte offset (inclusive)
*
* Return Value: On success, 0 is retured. On errors, one of the following
* negative error code is returned.
@@ -2639,8 +2661,8 @@
*
* %-ENOMEM - Insufficient memory available.
*/
-int nilfs_construct_dsync_segment(struct super_block *sb,
- struct inode *inode)
+int nilfs_construct_dsync_segment(struct super_block *sb, struct inode *inode,
+ loff_t start, loff_t end)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
struct nilfs_sc_info *sci = NILFS_SC(sbi);
@@ -2671,7 +2693,9 @@
return 0;
}
spin_unlock(&sbi->s_inode_lock);
- sci->sc_stage.dirty_file_ptr = ii;
+ sci->sc_dsync_inode = ii;
+ sci->sc_dsync_start = start;
+ sci->sc_dsync_end = end;
err = nilfs_segctor_do_construct(sci, SC_LSEG_DSYNC);