ceph: new mount option to disable usage of copy-from op
Add a new mount option 'nocopyfrom' that will prevent the usage of the
RADOS 'copy-from' operation in cephfs. This could be useful, for example,
for an administrator to temporarily mitigate any possible bugs in the
'copy-from' implementation.
Currently, only copy_file_range uses this RADOS operation. Setting this
mount option will result in this syscall reverting to the default VFS
implementation, i.e. to perform the copies locally instead of doing remote
object copies.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index eab1359..b5ecd6f 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -165,6 +165,8 @@
Opt_noacl,
Opt_quotadf,
Opt_noquotadf,
+ Opt_copyfrom,
+ Opt_nocopyfrom,
};
static match_table_t fsopt_tokens = {
@@ -203,6 +205,8 @@
{Opt_noacl, "noacl"},
{Opt_quotadf, "quotadf"},
{Opt_noquotadf, "noquotadf"},
+ {Opt_copyfrom, "copyfrom"},
+ {Opt_nocopyfrom, "nocopyfrom"},
{-1, NULL}
};
@@ -355,6 +359,12 @@
case Opt_noquotadf:
fsopt->flags |= CEPH_MOUNT_OPT_NOQUOTADF;
break;
+ case Opt_copyfrom:
+ fsopt->flags &= ~CEPH_MOUNT_OPT_NOCOPYFROM;
+ break;
+ case Opt_nocopyfrom:
+ fsopt->flags |= CEPH_MOUNT_OPT_NOCOPYFROM;
+ break;
#ifdef CONFIG_CEPH_FS_POSIX_ACL
case Opt_acl:
fsopt->sb_flags |= SB_POSIXACL;
@@ -553,6 +563,9 @@
seq_puts(m, ",noacl");
#endif
+ if (fsopt->flags & CEPH_MOUNT_OPT_NOCOPYFROM)
+ seq_puts(m, ",nocopyfrom");
+
if (fsopt->mds_namespace)
seq_show_option(m, "mds_namespace", fsopt->mds_namespace);
if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)