ceph: drop support for preferred_osd pgs

This was an ill-conceived feature that has been removed from Ceph.  Do
this gracefully:

 - reject attempts to specify a preferred_osd via the ioctl
 - stop exposing this information via virtual xattrs
 - always fill in -1 for requests, in case we talk to an older server
 - don't calculate preferred_osd placements/pgids

Reviewed-by: Alex Elder <elder@inktank.com>
Signed-off-by: Sage Weil <sage@inktank.com>

3 files changed, 5 insertions, 20 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index ed72428d9c75..988d4f302e48 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -54,7 +54,6 @@ prepare_open_request(struct super_block *sb, int flags, int create_mode)
         req->r_fmode = ceph_flags_to_mode(flags);
         req->r_args.open.flags = cpu_to_le32(flags);
         req->r_args.open.mode = cpu_to_le32(create_mode);
-        req->r_args.open.preferred = cpu_to_le32(-1);
 out:
         return req;
 }
diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
index 790914a598dd..4feab52c5bff 100644
--- a/fs/ceph/ioctl.c
+++ b/fs/ceph/ioctl.c
@@ -26,8 +26,7 @@ static long ceph_ioctl_get_layout(struct file *file, void __user *arg)
                 l.stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
                 l.object_size = ceph_file_layout_object_size(ci->i_layout);
                 l.data_pool = le32_to_cpu(ci->i_layout.fl_pg_pool);
-                l.preferred_osd =
-                        (s32)le32_to_cpu(ci->i_layout.fl_pg_preferred);
+                l.preferred_osd = (s32)-1;
                 if (copy_to_user(arg, &l, sizeof(l)))
                         return -EFAULT;
         }
@@ -49,6 +48,10 @@ static long ceph_ioctl_set_layout(struct file *file, void __user *arg)
         if (copy_from_user(&l, arg, sizeof(l)))
                 return -EFAULT;
 
+        /* preferred_osd is no longer supported */
+        if (l.preferred_osd != -1)
+                return -EINVAL;
+
         /* validate changed params against current layout */
         err = ceph_do_getattr(file->f_dentry->d_inode, CEPH_STAT_CAP_LAYOUT);
         if (!err) {
@@ -56,8 +59,6 @@ static long ceph_ioctl_set_layout(struct file *file, void __user *arg)
                 nl.stripe_count = ceph_file_layout_stripe_count(ci->i_layout);
                 nl.object_size = ceph_file_layout_object_size(ci->i_layout);
                 nl.data_pool = le32_to_cpu(ci->i_layout.fl_pg_pool);
-                nl.preferred_osd =
-                                (s32)le32_to_cpu(ci->i_layout.fl_pg_preferred);
         } else
                 return err;
 
@@ -69,8 +70,6 @@ static long ceph_ioctl_set_layout(struct file *file, void __user *arg)
                 nl.object_size = l.object_size;
         if (l.data_pool)
                 nl.data_pool = l.data_pool;
-        if (l.preferred_osd)
-                nl.preferred_osd = l.preferred_osd;
 
         if ((nl.object_size & ~PAGE_MASK) ||
             (nl.stripe_unit & ~PAGE_MASK) ||
@@ -106,8 +105,6 @@ static long ceph_ioctl_set_layout(struct file *file, void __user *arg)
         req->r_args.setlayout.layout.fl_object_size =
                 cpu_to_le32(l.object_size);
         req->r_args.setlayout.layout.fl_pg_pool = cpu_to_le32(l.data_pool);
-        req->r_args.setlayout.layout.fl_pg_preferred =
-                cpu_to_le32(l.preferred_osd);
 
         parent_inode = ceph_get_dentry_parent_inode(file->f_dentry);
         err = ceph_mdsc_do_request(mdsc, parent_inode, req);
@@ -171,8 +168,6 @@ static long ceph_ioctl_set_layout_policy (struct file *file, void __user *arg)
                         cpu_to_le32(l.object_size);
         req->r_args.setlayout.layout.fl_pg_pool =
                         cpu_to_le32(l.data_pool);
-        req->r_args.setlayout.layout.fl_pg_preferred =
-                        cpu_to_le32(l.preferred_osd);
 
         err = ceph_mdsc_do_request(mdsc, inode, req);
         ceph_mdsc_put_request(req);
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 35b86331d8a5..785cb3057c95 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -118,15 +118,6 @@ static size_t ceph_vxattrcb_file_layout(struct ceph_inode_info *ci, char *val,
                 (unsigned long long)ceph_file_layout_su(ci->i_layout),
                 (unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
                 (unsigned long long)ceph_file_layout_object_size(ci->i_layout));
-
-        if (ceph_file_layout_pg_preferred(ci->i_layout) >= 0) {
-                val += ret;
-                size -= ret;
-                ret += snprintf(val, size, "preferred_osd=%lld\n",
-                            (unsigned long long)ceph_file_layout_pg_preferred(
-                                    ci->i_layout));
-        }
-
         return ret;
 }