jbd2: change jbd2_journal_invalidatepage to accept length

invalidatepage now accepts range to invalidate and there are two file
system using jbd2 also implementing punch hole feature which can benefit
from this. We need to implement the same thing for jbd2 layer in order to
allow those file system take benefit of this functionality.

This commit adds length argument to the jbd2_journal_invalidatepage()
and updates all instances in ext4 and ocfs2.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 19d6ca27c8793eebacbd52b6b50b4fd6ebc9d5b8..694645e51fe002b0c506639e1cf916dcf6f488ca 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3015,7 +3015,8 @@ static int __ext4_journalled_invalidatepage(struct page *page,
        if (offset == 0)
                ClearPageChecked(page);
 
-       return jbd2_journal_invalidatepage(journal, page, offset);
+       return jbd2_journal_invalidatepage(journal, page, offset,
+                                          PAGE_CACHE_SIZE - offset);
 }
 
 /* Wrapper for aops... */

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 10f524c59ea88d48bf4f85f42e6fb2eca0d7a55b..5d8268ad364aab996d1609507ec7896fb721a13f 100644 (file)
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -2034,18 +2034,23 @@ zap_buffer_unlocked:
  * void jbd2_journal_invalidatepage()
  * @journal: journal to use for flush...
  * @page:    page to flush
- * @offset:  length of page to invalidate.
+ * @offset:  start of the range to invalidate
+ * @length:  length of the range to invalidate
  *
- * Reap page buffers containing data after offset in page. Can return -EBUSY
- * if buffers are part of the committing transaction and the page is straddling
- * i_size. Caller then has to wait for current commit and try again.
+ * Reap page buffers containing data after in the specified range in page.
+ * Can return -EBUSY if buffers are part of the committing transaction and
+ * the page is straddling i_size. Caller then has to wait for current commit
+ * and try again.
  */
 int jbd2_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;
        int ret = 0;
 
@@ -2054,6 +2059,8 @@ int jbd2_journal_invalidatepage(journal_t *journal,
        if (!page_has_buffers(page))
                return 0;
 
+       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. */
@@ -2063,10 +2070,13 @@ int jbd2_journal_invalidatepage(journal_t *journal,
                unsigned int next_off = curr_off + bh->b_size;
                next = bh->b_this_page;
 
+               if (next_off > stop)
+                       return 0;
+
                if (offset <= curr_off) {
                        /* This block is wholly outside the truncation point */
                        lock_buffer(bh);
-                       ret = journal_unmap_buffer(journal, bh, offset > 0);
+                       ret = journal_unmap_buffer(journal, bh, partial_page);
                        unlock_buffer(bh);
                        if (ret < 0)
                                return ret;
@@ -2077,7 +2087,7 @@ int jbd2_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/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index ecb86ca8b1f1202e5d2d9c54e7b048be63c90f5d..7c477559f38e5125c0292853ae62ca7bbbe0191c 100644 (file)
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -608,7 +608,8 @@ static void ocfs2_invalidatepage(struct page *page, unsigned int offset,
 {
        journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
 
-       jbd2_journal_invalidatepage(journal, page, offset);
+       jbd2_journal_invalidatepage(journal, page, offset,
+                                   PAGE_CACHE_SIZE - offset);
 }
 
 static int ocfs2_releasepage(struct page *page, gfp_t wait)

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 6e051f472edb6db62f7e292b71c3bc5b2c5575f5..682a63c34d26fca3436d9da326029eb2dddd4995 100644 (file)
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1090,7 +1090,7 @@ extern int         jbd2_journal_dirty_metadata (handle_t *, struct buffer_head *);
 extern int      jbd2_journal_forget (handle_t *, struct buffer_head *);
 extern void     journal_sync_buffer (struct buffer_head *);
 extern int      jbd2_journal_invalidatepage(journal_t *,
-                               struct page *, unsigned long);
+                               struct page *, unsigned int, unsigned int);
 extern int      jbd2_journal_try_to_free_buffers(journal_t *, struct page *, gfp_t);
 extern int      jbd2_journal_stop(handle_t *);
 extern int      jbd2_journal_flush (journal_t *);