[PATCH v4 04/20] jbd: change journal_invalidatepage() to accept length

Lukas Czerner
2013-05-14T16:37:18Z

->invalidatepage() aop now accepts range to invalidate so we can make
use of it in journal_invalidatepage() and all the users in ext3 file
system. Also update ext3 trace point to print out length argument.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
---
fs/ext3/inode.c | 6 +++---
fs/jbd/transaction.c | 19 ++++++++++++++-----
include/linux/jbd.h | 2 +-
include/trace/events/ext3.h | 12 +++++++-----
4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 349d4ce..b12936b 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1828,15 +1828,15 @@ static void ext3_invalidatepage(struct page *page, unsigned int offset,
{
journal_t *journal = EXT3_JOURNAL(page->mapping->host);

- trace_ext3_invalidatepage(page, offset);
+ trace_ext3_invalidatepage(page, offset, length);

/*
* If it's a full truncate we just forget about the pending dirtying
*/
- if (offset == 0)
+ if (offset == 0 && length == PAGE_CACHE_SIZE)
ClearPageChecked(page);

- journal_invalidatepage(journal, page, offset);
+ journal_invalidatepage(journal, page, offset, length);
}

static int ext3_releasepage(struct page *page, gfp_t wait)
diff --git a/fs/jbd/transaction.c b/fs/jbd/transaction.c
index 071d690..a1fef89 100644
--- a/fs/jbd/transaction.c
+++ b/fs/jbd/transaction.c
@@ -2020,16 +2020,20 @@ zap_buffer_unlocked:
* void journal_invalidatepage() - invalidate a journal page
* @journal: journal to use for flush
* @page: page to flush
- * @offset: length of page to invalidate.
+ * @offset: offset of the range to invalidate
+ * @length: length of the range to invalidate
*
- * Reap page buffers containing data after offset in page.
+ * Reap page buffers containing data in specified range in page.
*/
void journal_invalidatepage(journal_t *journal,
struct page *page,
- unsigned long offset)
+ unsigned int offset,
+ unsigned int length)
{
struct buffer_head *head, *bh, *next;
+ unsigned int stop = offset + length;
unsigned int curr_off = 0;
+ int partial_page = (offset || length < PAGE_CACHE_SIZE);
int may_free = 1;

if (!PageLocked(page))
@@ -2037,6 +2041,8 @@ void journal_invalidatepage(journal_t *journal,
if (!page_has_buffers(page))
return;

+ BUG_ON(stop > PAGE_CACHE_SIZE || stop < length);
+
/* We will potentially be playing with lists other than just the
* data lists (especially for journaled data mode), so be
* cautious in our locking. */
@@ -2046,11 +2052,14 @@ void journal_invalidatepage(journal_t *journal,
unsigned int next_off = curr_off + bh->b_size;
next = bh->b_this_page;

+ if (next_off > stop)
+ return;
+
if (offset <= curr_off) {
/* This block is wholly outside the truncation point */
lock_buffer(bh);
may_free &= journal_unmap_buffer(journal, bh,
- offset > 0);
+ partial_page);
unlock_buffer(bh);
}
curr_off = next_off;
@@ -2058,7 +2067,7 @@ void journal_invalidatepage(journal_t *journal,

} while (bh != head);

- if (!offset) {
+ if (!partial_page) {
if (may_free && try_to_free_buffers(page))
J_ASSERT(!page_has_buffers(page));
}
diff --git a/include/linux/jbd.h b/include/linux/jbd.h
index c8f3297..d02e16c 100644
--- a/include/linux/jbd.h
+++ b/include/linux/jbd.h
@@ -840,7 +840,7 @@ extern void journal_release_buffer (handle_t *, struct buffer_head *);
extern int journal_forget (handle_t *, struct buffer_head *);
extern void journal_sync_buffer (struct buffer_head *);
extern void journal_invalidatepage(journal_t *,
- struct page *, unsigned long);
+ struct page *, unsigned int, unsigned int);
extern int journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
extern int journal_stop(handle_t *);
extern int journal_flush (journal_t *);
diff --git a/include/trace/events/ext3.h b/include/trace/events/ext3.h
index 15d11a3..6797b9d 100644
--- a/include/trace/events/ext3.h
+++ b/include/trace/events/ext3.h
@@ -290,13 +290,14 @@ DEFINE_EVENT(ext3__page_op, ext3_releasepage,
);

TRACE_EVENT(ext3_invalidatepage,
- TP_PROTO(struct page *page, unsigned long offset),
+ TP_PROTO(struct page *page, unsigned int offset, unsigned int length),

- TP_ARGS(page, offset),
+ TP_ARGS(page, offset, length),

TP_STRUCT__entry(
__field( pgoff_t, index )
- __field( unsigned long, offset )
+ __field( unsigned int, offset )
+ __field( unsigned int, length )
__field( ino_t, ino )
__field( dev_t, dev )

@@ -305,14 +306,15 @@ TRACE_EVENT(ext3_invalidatepage,
TP_fast_assign(
__entry->index = page->index;
__entry->offset = offset;
+ __entry->length = length;
__entry->ino = page->mapping->host->i_ino;
__entry->dev = page->mapping->host->i_sb->s_dev;
),

- TP_printk("dev %d,%d ino %lu page_index %lu offset %lu",
+ TP_printk("dev %d,%d ino %lu page_index %lu offset %u length %u",
MAJOR(__entry->dev), MINOR(__entry->dev),
(unsigned long) __entry->ino,
- __entry->index, __entry->offset)
+ __entry->index, __entry->offset, __entry->length)
);

TRACE_EVENT(ext3_discard_blocks,