NTFS: - Split ntfs_map_runlist() into ntfs_map_runlist() and a non-locking
helper ntfs_map_runlist_nolock() which is used by ntfs_map_runlist().
This allows us to map runlist fragments with the runlist lock already
held without having to drop and reacquire it around the call. Adapt
all callers.
- Change ntfs_find_vcn() to ntfs_find_vcn_nolock() which takes a locked
runlist. This allows us to find runlist elements with the runlist
lock already held without having to drop and reacquire it around the
call. Adapt all callers.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
diff --git a/fs/ntfs/lcnalloc.c b/fs/ntfs/lcnalloc.c
index 5346596..8db4492 100644
--- a/fs/ntfs/lcnalloc.c
+++ b/fs/ntfs/lcnalloc.c
@@ -849,7 +849,8 @@
total_freed = real_freed = 0;
/* This returns with ni->runlist locked for reading on success. */
- rl = ntfs_find_vcn(ni, start_vcn, FALSE);
+ down_read(&ni->runlist.lock);
+ rl = ntfs_find_vcn_nolock(ni, start_vcn, FALSE);
if (IS_ERR(rl)) {
if (!is_rollback)
ntfs_error(vol->sb, "Failed to find first runlist "
@@ -863,7 +864,7 @@
ntfs_error(vol->sb, "First runlist element has "
"invalid lcn, aborting.");
err = -EIO;
- goto unl_err_out;
+ goto err_out;
}
/* Find the starting cluster inside the run that needs freeing. */
delta = start_vcn - rl->vcn;
@@ -881,7 +882,7 @@
if (!is_rollback)
ntfs_error(vol->sb, "Failed to clear first run "
"(error %i), aborting.", err);
- goto unl_err_out;
+ goto err_out;
}
/* We have freed @to_free real clusters. */
real_freed = to_free;
@@ -901,30 +902,15 @@
if (unlikely(rl->lcn < LCN_HOLE)) {
VCN vcn;
- /*
- * Attempt to map runlist, dropping runlist lock for
- * the duration.
- */
+ /* Attempt to map runlist. */
vcn = rl->vcn;
- up_read(&ni->runlist.lock);
- err = ntfs_map_runlist(ni, vcn);
- if (err) {
- if (!is_rollback)
- ntfs_error(vol->sb, "Failed to map "
- "runlist fragment.");
- if (err == -EINVAL || err == -ENOENT)
- err = -EIO;
- goto err_out;
- }
- /*
- * This returns with ni->runlist locked for reading on
- * success.
- */
- rl = ntfs_find_vcn(ni, vcn, FALSE);
+ rl = ntfs_find_vcn_nolock(ni, vcn, FALSE);
if (IS_ERR(rl)) {
err = PTR_ERR(rl);
if (!is_rollback)
- ntfs_error(vol->sb, "Failed to find "
+ ntfs_error(vol->sb, "Failed to map "
+ "runlist fragment or "
+ "failed to find "
"subsequent runlist "
"element.");
goto err_out;
@@ -937,7 +923,7 @@
(unsigned long long)
rl->lcn);
err = -EIO;
- goto unl_err_out;
+ goto err_out;
}
}
/* The number of clusters in this run that need freeing. */
@@ -953,7 +939,7 @@
if (!is_rollback)
ntfs_error(vol->sb, "Failed to clear "
"subsequent run.");
- goto unl_err_out;
+ goto err_out;
}
/* We have freed @to_free real clusters. */
real_freed += to_free;
@@ -974,9 +960,8 @@
/* We are done. Return the number of actually freed clusters. */
ntfs_debug("Done.");
return real_freed;
-unl_err_out:
- up_read(&ni->runlist.lock);
err_out:
+ up_read(&ni->runlist.lock);
if (is_rollback)
return err;
/* If no real clusters were freed, no need to rollback. */