On Thu, Mar 15, 2007 at 05:17:04PM +0100, Nick Piggin wrote:
> (excludes the OCFS2 patch that Mark sent, in anticipation of an update)
Attached is said patch. I needed to export __grab_cache_page (ext2/ext3 also
need this if they're to be built as modules), so a patch to do that is also
attached.
This passed some preliminary testing on a two node cluster I have here at
Oracle.
--Mark
--
Mark Fasheh
Senior Software Developer, Oracle
mark.fasheh@xxxxxxxxxx
From: Mark Fasheh <mark.fasheh@xxxxxxxxxx>
ocfs2: Convert to new aops
Turn ocfs2_prepare_write() and ocfs2_commit_write() into ocfs2_write_begin()
and ocfs2_write_end(). This conveniently eliminates the need for
AOP_TRUNCATED_PAGE during write.
Signed-off-by: Mark Fasheh <mark.fasheh@xxxxxxxxxx>
e28911070b02362a9a3a543646da84a8fbf9f63b
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 875c114..cbec0e1 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -293,29 +293,67 @@ int ocfs2_prepare_write_nolock(struct in
}
/*
- * ocfs2_prepare_write() can be an outer-most ocfs2 call when it is called
- * from loopback. It must be able to perform its own locking around
- * ocfs2_get_block().
+ * ocfs2_write_begin() can be an outer-most ocfs2 call when it is
+ * called from elsewhere in the kernel. It must be able to perform its
+ * own locking around ocfs2_get_block().
*/
-static int ocfs2_prepare_write(struct file *file, struct page *page,
- unsigned from, unsigned to)
+static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
{
- struct inode *inode = page->mapping->host;
+ struct inode *inode = mapping->host;
+ struct buffer_head *di_bh = NULL;
+ struct page *page = NULL;
int ret;
- mlog_entry("(0x%p, 0x%p, %u, %u)\n", file, page, from, to);
-
- ret = ocfs2_meta_lock_with_page(inode, NULL, 0, page);
+ ret = ocfs2_meta_lock(inode, &di_bh, 1);
if (ret != 0) {
mlog_errno(ret);
+ return ret;
+ }
+
+ ret = ocfs2_data_lock(inode, 1);
+ if (ret) {
+ ocfs2_meta_unlock(inode, 1);
+
+ mlog_errno(ret);
+ return ret;
+ }
+
+ /*
+ * Lock the page out here to preserve ordering with
+ * ip_alloc_sem.
+ */
+ page = __grab_cache_page(mapping, pos >> PAGE_CACHE_SHIFT);
+ if (!page) {
+ ret = -ENOMEM;
+ mlog_errno(ret);
goto out;
}
- ret = ocfs2_prepare_write_nolock(inode, page, from, to);
+ *pagep = page;
- ocfs2_meta_unlock(inode, 0);
+ down_read(&OCFS2_I(inode)->ip_alloc_sem);
+ ret = block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+ ocfs2_get_block);
+ up_read(&OCFS2_I(inode)->ip_alloc_sem);
out:
- mlog_exit(ret);
+ if (ret == 0) {
+ *fsdata = di_bh;
+ } else {
+ /*
+ * Error return - the caller won't call
+ * ocfs2_write_end, so drop cluster locks here.
+ */
+ brelse(di_bh);
+ if (page) {
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ ocfs2_data_unlock(inode, 1);
+ ocfs2_meta_unlock(inode, 1);
+ }
+
return ret;
}
@@ -388,16 +426,18 @@ out:
return handle;
}
-static int ocfs2_commit_write(struct file *file, struct page *page,
- unsigned from, unsigned to)
+static int ocfs2_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
int ret;
- struct buffer_head *di_bh = NULL;
+ unsigned from, to;
+ struct buffer_head *di_bh = fsdata;
struct inode *inode = page->mapping->host;
handle_t *handle = NULL;
struct ocfs2_dinode *di;
- mlog_entry("(0x%p, 0x%p, %u, %u)\n", file, page, from, to);
+ mlog_entry("(0x%p, 0x%p)\n", file, page);
/* NOTE: ocfs2_file_aio_write has ensured that it's safe for
* us to continue here without rechecking the I/O against
@@ -412,22 +452,13 @@ static int ocfs2_commit_write(struct fil
* stale inode allocation image (i_size, i_clusters, etc).
*/
- ret = ocfs2_meta_lock_with_page(inode, &di_bh, 1, page);
- if (ret != 0) {
- mlog_errno(ret);
- goto out;
- }
-
- ret = ocfs2_data_lock_with_page(inode, 1, page);
- if (ret != 0) {
- mlog_errno(ret);
- goto out_unlock_meta;
- }
+ from = pos & (PAGE_CACHE_SIZE - 1);
+ to = from + len;
handle = ocfs2_start_walk_page_trans(inode, page, from, to);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
- goto out_unlock_data;
+ goto out_unlock;
}
/* Mark our buffer early. We'd rather catch this error up here
@@ -441,8 +472,10 @@ static int ocfs2_commit_write(struct fil
}
/* might update i_size */
- ret = generic_commit_write(file, page, from, to);
- if (ret < 0) {
+ copied = block_write_end(file, mapping, pos, len, copied, page, fsdata);
+ if (copied < 0) {
+ ret = copied;
+ copied = 0;
mlog_errno(ret);
goto out_commit;
}
@@ -458,23 +491,30 @@ static int ocfs2_commit_write(struct fil
di->i_size = cpu_to_le64((u64)i_size_read(inode));
ret = ocfs2_journal_dirty(handle, di_bh);
- if (ret < 0) {
+ if (ret < 0)
mlog_errno(ret);
- goto out_commit;
- }
+ ret = 0;
out_commit:
ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
-out_unlock_data:
+out_unlock:
ocfs2_data_unlock(inode, 1);
-out_unlock_meta:
ocfs2_meta_unlock(inode, 1);
-out:
+
+ if (ret) {
+ /*
+ * We caught an error before block_write_end() -
+ * unlock and free the page.
+ */
+ unlock_page(page);
+ page_cache_release(page);
+ }
+
if (di_bh)
brelse(di_bh);
mlog_exit(ret);
- return ret;
+ return copied ? copied : ret;
}
static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
@@ -678,8 +718,8 @@ out:
const struct address_space_operations ocfs2_aops = {
.readpage = ocfs2_readpage,
.writepage = ocfs2_writepage,
- .prepare_write = ocfs2_prepare_write,
- .commit_write = ocfs2_commit_write,
+ .write_begin = ocfs2_write_begin,
+ .write_end = ocfs2_write_end,
.bmap = ocfs2_bmap,
.sync_page = block_sync_page,
.direct_IO = ocfs2_direct_IO,
--
1.3.3
From: Mark Fasheh <mark.fasheh@xxxxxxxxxx>
[PATCH] Export __grab_cache_page
Needed at least by ocfs2 and ext[23].
Signed-off-by: Mark Fasheh <mark.fasheh@xxxxxxxxxx>
ec4c66f0e6012a182105405aa11813fbf836629f
diff --git a/mm/filemap.c b/mm/filemap.c
index 327c20f..c4a2d68 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2196,6 +2196,7 @@ repeat:
}
return page;
}
+EXPORT_SYMBOL(__grab_cache_page);
static ssize_t generic_perform_write_2copy(struct file *file,
struct iov_iter *i, loff_t pos)
--
1.3.3
