ceph: refactor ceph_unreserve_caps()

The code of ceph_unreserve_caps() and error handling in
ceph_reserve_caps() are duplicated, so introduce a helper
__ceph_unreserve_caps() to reduce duplicated code.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

2 files changed, 37 insertions, 31 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index f50cc008632a..fb4a19ee5b6d 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -156,6 +156,37 @@ void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta)
         spin_unlock(&mdsc->caps_list_lock);
 }
 
+static void __ceph_unreserve_caps(struct ceph_mds_client *mdsc, int nr_caps)
+{
+        struct ceph_cap *cap;
+        int i;
+
+        if (nr_caps) {
+                BUG_ON(mdsc->caps_reserve_count < nr_caps);
+                mdsc->caps_reserve_count -= nr_caps;
+                if (mdsc->caps_avail_count >=
+                    mdsc->caps_reserve_count + mdsc->caps_min_count) {
+                        mdsc->caps_total_count -= nr_caps;
+                        for (i = 0; i < nr_caps; i++) {
+                                cap = list_first_entry(&mdsc->caps_list,
+                                        struct ceph_cap, caps_item);
+                                list_del(&cap->caps_item);
+                                kmem_cache_free(ceph_cap_cachep, cap);
+                        }
+                } else {
+                        mdsc->caps_avail_count += nr_caps;
+                }
+
+                dout("%s: caps %d = %d used + %d resv + %d avail\n",
+                     __func__,
+                     mdsc->caps_total_count, mdsc->caps_use_count,
+                     mdsc->caps_reserve_count, mdsc->caps_avail_count);
+                BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
+                                                 mdsc->caps_reserve_count +
+                                                 mdsc->caps_avail_count);
+        }
+}
+
 /*
  * Called under mdsc->mutex.
  */
@@ -283,39 +314,14 @@ out_nomem:
         return -ENOMEM;
 }
 
-int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
+void ceph_unreserve_caps(struct ceph_mds_client *mdsc,
                         struct ceph_cap_reservation *ctx)
 {
-        int i;
-        struct ceph_cap *cap;
-
         dout("unreserve caps ctx=%p count=%d\n", ctx, ctx->count);
-        if (ctx->count) {
-                spin_lock(&mdsc->caps_list_lock);
-                BUG_ON(mdsc->caps_reserve_count < ctx->count);
-                mdsc->caps_reserve_count -= ctx->count;
-                if (mdsc->caps_avail_count >=
-                    mdsc->caps_reserve_count + mdsc->caps_min_count) {
-                        mdsc->caps_total_count -= ctx->count;
-                        for (i = 0; i < ctx->count; i++) {
-                                cap = list_first_entry(&mdsc->caps_list,
-                                        struct ceph_cap, caps_item);
-                                list_del(&cap->caps_item);
-                                kmem_cache_free(ceph_cap_cachep, cap);
-                        }
-                } else {
-                        mdsc->caps_avail_count += ctx->count;
-                }
-                ctx->count = 0;
-                dout("unreserve caps %d = %d used + %d resv + %d avail\n",
-                     mdsc->caps_total_count, mdsc->caps_use_count,
-                     mdsc->caps_reserve_count, mdsc->caps_avail_count);
-                BUG_ON(mdsc->caps_total_count != mdsc->caps_use_count +
-                                                 mdsc->caps_reserve_count +
-                                                 mdsc->caps_avail_count);
-                spin_unlock(&mdsc->caps_list_lock);
-        }
-        return 0;
+        spin_lock(&mdsc->caps_list_lock);
+        __ceph_unreserve_caps(mdsc, ctx->count);
+        ctx->count = 0;
+        spin_unlock(&mdsc->caps_list_lock);
 }
 
 struct ceph_cap *ceph_get_cap(struct ceph_mds_client *mdsc,
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index f09dbf2a2e26..9b5f15d20b33 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -656,7 +656,7 @@ extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
 extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
                              struct ceph_cap_reservation *ctx, int need);
-extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
+extern void ceph_unreserve_caps(struct ceph_mds_client *mdsc,
                                struct ceph_cap_reservation *ctx);
 extern void ceph_reservation_status(struct ceph_fs_client *client,
                                     int *total, int *avail, int *used,