xfs: remove xfs_itruncate_data
This wrapper isn't overly useful, not to say rather confusing.
Around the call to xfs_itruncate_extents it does:
- add tracing
- add a few asserts in debug builds
- conditionally update the inode size in two places
- log the inode
Both the tracing and the inode logging can be moved to xfs_itruncate_extents
as they are useful for the attribute fork as well - in fact the attr code
already does an equivalent xfs_trans_log_inode call just after calling
xfs_itruncate_extents. The conditional size updates are a mess, and there
was no reason to do them in two places anyway, as the first one was
conditional on the inode having extents - but without extents we
xfs_itruncate_extents would be a no-op and the placement wouldn't matter
anyway. Instead move the size assignments and the asserts that make sense
to the callers that want it.
As a side effect of this clean up xfs_setattr_size by introducing variables
for the old and new inode size, and moving the size updates into a common
place.
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index f9babd1..f02eaa2 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -750,6 +750,7 @@
struct xfs_mount *mp = ip->i_mount;
struct inode *inode = VFS_I(ip);
int mask = iattr->ia_valid;
+ xfs_off_t oldsize, newsize;
struct xfs_trans *tp;
int error;
uint lock_flags;
@@ -777,11 +778,13 @@
lock_flags |= XFS_IOLOCK_EXCL;
xfs_ilock(ip, lock_flags);
+ oldsize = ip->i_size;
+ newsize = iattr->ia_size;
+
/*
* Short circuit the truncate case for zero length files.
*/
- if (iattr->ia_size == 0 &&
- ip->i_size == 0 && ip->i_d.di_nextents == 0) {
+ if (newsize == 0 && oldsize == 0 && ip->i_d.di_nextents == 0) {
if (!(mask & (ATTR_CTIME|ATTR_MTIME)))
goto out_unlock;
@@ -807,14 +810,14 @@
* the inode to the transaction, because the inode cannot be unlocked
* once it is a part of the transaction.
*/
- if (iattr->ia_size > ip->i_size) {
+ if (newsize > oldsize) {
/*
* Do the first part of growing a file: zero any data in the
* last block that is beyond the old EOF. We need to do this
* before the inode is joined to the transaction to modify
* i_size.
*/
- error = xfs_zero_eof(ip, iattr->ia_size, ip->i_size);
+ error = xfs_zero_eof(ip, newsize, oldsize);
if (error)
goto out_unlock;
}
@@ -833,8 +836,8 @@
* here and prevents waiting for other data not within the range we
* care about here.
*/
- if (ip->i_size != ip->i_d.di_size && iattr->ia_size > ip->i_d.di_size) {
- error = xfs_flush_pages(ip, ip->i_d.di_size, iattr->ia_size, 0,
+ if (oldsize != ip->i_d.di_size && newsize > ip->i_d.di_size) {
+ error = xfs_flush_pages(ip, ip->i_d.di_size, newsize, 0,
FI_NONE);
if (error)
goto out_unlock;
@@ -845,8 +848,7 @@
*/
inode_dio_wait(inode);
- error = -block_truncate_page(inode->i_mapping, iattr->ia_size,
- xfs_get_blocks);
+ error = -block_truncate_page(inode->i_mapping, newsize, xfs_get_blocks);
if (error)
goto out_unlock;
@@ -857,7 +859,7 @@
if (error)
goto out_trans_cancel;
- truncate_setsize(inode, iattr->ia_size);
+ truncate_setsize(inode, newsize);
commit_flags = XFS_TRANS_RELEASE_LOG_RES;
lock_flags |= XFS_ILOCK_EXCL;
@@ -876,19 +878,30 @@
* these flags set. For all other operations the VFS set these flags
* explicitly if it wants a timestamp update.
*/
- if (iattr->ia_size != ip->i_size &&
- (!(mask & (ATTR_CTIME | ATTR_MTIME)))) {
+ if (newsize != oldsize && (!(mask & (ATTR_CTIME | ATTR_MTIME)))) {
iattr->ia_ctime = iattr->ia_mtime =
current_fs_time(inode->i_sb);
mask |= ATTR_CTIME | ATTR_MTIME;
}
- if (iattr->ia_size > ip->i_size) {
- ip->i_d.di_size = iattr->ia_size;
- ip->i_size = iattr->ia_size;
- } else if (iattr->ia_size <= ip->i_size ||
- (iattr->ia_size == 0 && ip->i_d.di_nextents)) {
- error = xfs_itruncate_data(&tp, ip, iattr->ia_size);
+ /*
+ * The first thing we do is set the size to new_size permanently on
+ * disk. This way we don't have to worry about anyone ever being able
+ * to look at the data being freed even in the face of a crash.
+ * What we're getting around here is the case where we free a block, it
+ * is allocated to another file, it is written to, and then we crash.
+ * If the new data gets written to the file but the log buffers
+ * containing the free and reallocation don't, then we'd end up with
+ * garbage in the blocks being freed. As long as we make the new size
+ * permanent before actually freeing any blocks it doesn't matter if
+ * they get written to.
+ */
+ ip->i_d.di_size = newsize;
+ ip->i_size = newsize;
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+
+ if (newsize <= oldsize) {
+ error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK, newsize);
if (error)
goto out_trans_abort;