From: NeilBrown <neilb@suse.de>
Date: Sun, 12 Sep 2010 23:46:36 +0000 (+1000)
Subject: Clean up error returns in lafs_reserve_block
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=4d88ac01c1cd69759b4a30e72f7c1336d91bb77b;p=LaFS.git

Clean up error returns in lafs_reserve_block

We only want to consider EAGAIN if lafs_prealloc returns an error.
When other calls return an error, we want to pass exactly that error
back.

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/block.c b/block.c
index 15959e0..58af84d 100644
--- a/block.c
+++ b/block.c
@@ -380,6 +380,8 @@ lafs_reserve_block(struct block *b, int alloc_type)
 			 b);
 	else
 		err = lafs_setparent(dblk(b));
+	if (err)
+		return err;
 
 	/* If there is already a physaddr, or the data is
 	 * stored in the inode, then we aren't really allocating
@@ -404,16 +406,30 @@ lafs_reserve_block(struct block *b, int alloc_type)
 	 */
 	in_emergency = test_bit(EmergencyClean, &fs->fsstate);
 	/* Allocate space in the filesystem */
-	err = err ?: lafs_prealloc(b, alloc_type);
+	err = lafs_prealloc(b, alloc_type);
+	if (err) {
+		if (alloc_type == NewSpace) {
+			if (in_emergency)
+				return -ENOSPC;
+			return -EAGAIN;
+		}
+		if (alloc_type == ReleaseSpace)
+			return -EAGAIN;
+		LAFS_BUG(1, b);
+	}
 
 	/* Allocate space in the file (and quota set) */
-	if (err == 0 && b->physaddr == 0 &&
+	if (b->physaddr == 0 &&
 	    !test_bit(B_Index, &b->flags) &&
 	    !test_and_set_bit(B_Prealloc, &b->flags)) {
 		err = lafs_summary_allocate(fs, b->inode, 1);
 		if (err)
 			clear_bit(B_Prealloc, &b->flags);
 	}
+	if (err) {
+		LAFS_BUG(alloc_type == AccountSpace, b);
+		return err;
+	}
 
 	/* Having reserved the block, we need to get a segref,
 	 * which will involve reserving those blocks too.
@@ -429,16 +445,7 @@ lafs_reserve_block(struct block *b, int alloc_type)
 	       && !test_bit(B_SegRef, &b->flags))
 		err = lafs_seg_ref_block(b, 0);
 
-	if (err == 0)
-		return 0;
-	if (alloc_type == NewSpace) {
-		if (in_emergency)
-			return -ENOSPC;
-		return -EAGAIN;
-	}
-	if (alloc_type == ReleaseSpace)
-		return -EAGAIN;
-	LAFS_BUG(1, b);
+	return err;
 }
 
 int