xfs: new truncate sequence
Convert XFS to the new truncate sequence. We still can have errors after
updating the file size in xfs_setattr, but these are real I/O errors and lead
to a transaction abort and filesystem shutdown, so they are not an issue.
Errors from ->write_begin and write_end can now be handled correctly because
we can actually get rid of the delalloc extents while previous the buffer
state was stipped in block_invalidatepage.
There is still no error handling for ->direct_IO, because doing so will need
some major restructuring given that we only have the iolock shared and do not
hold i_mutex at all. Fortunately leaving the normally allocated blocks behind
there is not a major issue and this will get cleaned up by xfs_free_eofblock
later.
Note: the patch is against Al's vfs.git tree as that contains the nessecary
preparations. I'd prefer to get it applied there so that we can get some
testing in linux-next.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index bf7aad0..15412fe 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -1494,6 +1494,22 @@
return ret;
}
+STATIC void
+xfs_vm_write_failed(
+ struct address_space *mapping,
+ loff_t to)
+{
+ struct inode *inode = mapping->host;
+
+ if (to > inode->i_size) {
+ struct iattr ia = {
+ .ia_valid = ATTR_SIZE | ATTR_FORCE,
+ .ia_size = inode->i_size,
+ };
+ xfs_setattr(XFS_I(inode), &ia, XFS_ATTR_NOLOCK);
+ }
+}
+
STATIC int
xfs_vm_write_begin(
struct file *file,
@@ -1508,12 +1524,26 @@
ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS,
pagep, xfs_get_blocks);
- if (unlikely(ret)) {
- loff_t isize = mapping->host->i_size;
- if (pos + len > isize)
- vmtruncate(mapping->host, isize);
- }
+ if (unlikely(ret))
+ xfs_vm_write_failed(mapping, pos + len);
+ return ret;
+}
+STATIC int
+xfs_vm_write_end(
+ struct file *file,
+ struct address_space *mapping,
+ loff_t pos,
+ unsigned len,
+ unsigned copied,
+ struct page *page,
+ void *fsdata)
+{
+ int ret;
+
+ ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
+ if (unlikely(ret < len))
+ xfs_vm_write_failed(mapping, pos + len);
return ret;
}
@@ -1559,7 +1589,7 @@
.releasepage = xfs_vm_releasepage,
.invalidatepage = xfs_vm_invalidatepage,
.write_begin = xfs_vm_write_begin,
- .write_end = generic_write_end,
+ .write_end = xfs_vm_write_end,
.bmap = xfs_vm_bmap,
.direct_IO = xfs_vm_direct_IO,
.migratepage = buffer_migrate_page,