nilfs2: return EBUSY against delete request on snapshot

This helps userland programs like the rmcp command to distinguish error codes returned against a checkpoint removal request. Previously -EPERM was returned, and not discriminable from real permission errors. This also allows removal of the latest checkpoint because the deletion leads to create a new checkpoint, and thus it's harmless for the filesystem. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

nilfs2: return EBUSY against delete request on snapshot
This helps userland programs like the rmcp command to distinguish error codes returned against a checkpoint removal request. Previously -EPERM was returned, and not discriminable from real permission errors. This also allows removal of the latest checkpoint because the deletion leads to create a new checkpoint, and thus it's harmless for the filesystem. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Ryusuke Konishi
1 parent fb6e7113ae
Showing 1 changed file with 2 additions and 12 deletions Side-by-side Diff
fs/nilfs2/cpfile.c
@@ -295,10 +295,6 @@
 		return -EINVAL;
 	}
  
-	/* cannot delete the latest checkpoint */
-	if (start == nilfs_mdt_cno(cpfile) - 1)
-		return -EPERM;
-
 	down_write(&NILFS_MDT(cpfile)->mi_sem);
  
 	ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
  
@@ -542,20 +538,14 @@
 	struct nilfs_cpinfo ci;
 	__u64 tcno = cno;
 	ssize_t nci;
-	int ret;
  
 	nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, sizeof(ci), 1);
 	if (nci < 0)
 		return nci;
 	else if (nci == 0 || ci.ci_cno != cno)
 		return -ENOENT;
-
-	/* cannot delete the latest checkpoint nor snapshots */
-	ret = nilfs_cpinfo_snapshot(&ci);
-	if (ret < 0)
-		return ret;
-	else if (ret > 0 || cno == nilfs_mdt_cno(cpfile) - 1)
-		return -EPERM;
+	else if (nilfs_cpinfo_snapshot(&ci))
+		return -EBUSY;
  
 	return nilfs_cpfile_delete_checkpoints(cpfile, cno, cno + 1);
 }
...	...	@@ -295,10 +295,6 @@
295	295	return -EINVAL;
296	296	}
297	297
298		- /* cannot delete the latest checkpoint */
299		- if (start == nilfs_mdt_cno(cpfile) - 1)
300		- return -EPERM;
301		-
302	298	down_write(&NILFS_MDT(cpfile)->mi_sem);
303	299
304	300	ret = nilfs_cpfile_get_header_block(cpfile, &header_bh);
305	301
...	...	@@ -542,20 +538,14 @@
542	538	struct nilfs_cpinfo ci;
543	539	__u64 tcno = cno;
544	540	ssize_t nci;
545		- int ret;
546	541
547	542	nci = nilfs_cpfile_do_get_cpinfo(cpfile, &tcno, &ci, sizeof(ci), 1);
548	543	if (nci < 0)
549	544	return nci;
550	545	else if (nci == 0 \|\| ci.ci_cno != cno)
551	546	return -ENOENT;
552		-
553		- /* cannot delete the latest checkpoint nor snapshots */
554		- ret = nilfs_cpinfo_snapshot(&ci);
555		- if (ret < 0)
556		- return ret;
557		- else if (ret > 0 \|\| cno == nilfs_mdt_cno(cpfile) - 1)
558		- return -EPERM;
	547	+ else if (nilfs_cpinfo_snapshot(&ci))
	548	+ return -EBUSY;
559	549
560	550	return nilfs_cpfile_delete_checkpoints(cpfile, cno, cno + 1);
561	551	}