LU-10018 protocol: MDT as a statfs proxy

[fs/lustre-release.git] / lustre / lod / lod_dev.c

diff --git a/lustre/lod/lod_dev.c b/lustre/lod/lod_dev.c
index 8d94449..6949283 100644 (file)
--- a/lustre/lod/lod_dev.c
+++ b/lustre/lod/lod_dev.c
@@ -1263,6 +1263,30 @@ static int lod_root_get(const struct lu_env *env,
        return dt_root_get(env, dt2lod_dev(dev)->lod_child, f);
 }
 
+static void lod_statfs_sum(struct obd_statfs *sfs,
+                            struct obd_statfs *ost_sfs, int *bs)
+{
+       while (ost_sfs->os_bsize < *bs) {
+               *bs >>= 1;
+               sfs->os_bsize >>= 1;
+               sfs->os_bavail <<= 1;
+               sfs->os_blocks <<= 1;
+               sfs->os_bfree <<= 1;
+               sfs->os_granted <<= 1;
+       }
+       while (ost_sfs->os_bsize > *bs) {
+               ost_sfs->os_bsize >>= 1;
+               ost_sfs->os_bavail <<= 1;
+               ost_sfs->os_blocks <<= 1;
+               ost_sfs->os_bfree <<= 1;
+               ost_sfs->os_granted <<= 1;
+       }
+       sfs->os_bavail += ost_sfs->os_bavail;
+       sfs->os_blocks += ost_sfs->os_blocks;
+       sfs->os_bfree += ost_sfs->os_bfree;
+       sfs->os_granted += ost_sfs->os_granted;
+}
+
 /**
  * Implementation of dt_device_operations::dt_statfs() for LOD
  *
@@ -1271,7 +1295,73 @@ static int lod_root_get(const struct lu_env *env,
 static int lod_statfs(const struct lu_env *env,
                      struct dt_device *dev, struct obd_statfs *sfs)
 {
-       return dt_statfs(env, dt2lod_dev(dev)->lod_child, sfs);
+       struct lod_device   *lod = dt2lod_dev(dev);
+       struct lod_ost_desc *ost;
+       struct lod_mdt_desc *mdt;
+       struct obd_statfs    ost_sfs;
+       int i, rc, bs;
+       bool mdtonly;
+
+       rc = dt_statfs(env, dt2lod_dev(dev)->lod_child, sfs);
+       if (rc)
+               GOTO(out, rc);
+
+       bs = sfs->os_bsize;
+
+       sfs->os_bavail = 0;
+       sfs->os_blocks = 0;
+       sfs->os_bfree = 0;
+       sfs->os_granted = 0;
+
+       lod_getref(&lod->lod_mdt_descs);
+       lod_foreach_mdt(lod, i) {
+               mdt = MDT_TGT(lod, i);
+               LASSERT(mdt && mdt->ltd_mdt);
+               rc = dt_statfs(env, mdt->ltd_mdt, &ost_sfs);
+               /* ignore errors */
+               if (rc)
+                       continue;
+               sfs->os_files += ost_sfs.os_files;
+               sfs->os_ffree += ost_sfs.os_ffree;
+               lod_statfs_sum(sfs, &ost_sfs, &bs);
+       }
+       lod_putref(lod, &lod->lod_mdt_descs);
+
+       /* at some point we can check whether DoM is enabled and
+        * decide how to account MDT space. for simplicity let's
+        * just fallback to pre-DoM policy if any OST is alive */
+       mdtonly = true;
+
+       lod_getref(&lod->lod_ost_descs);
+       lod_foreach_ost(lod, i) {
+               ost = OST_TGT(lod, i);
+               LASSERT(ost && ost->ltd_ost);
+               rc = dt_statfs(env, ost->ltd_ost, &ost_sfs);
+               /* ignore errors */
+               if (rc || ost_sfs.os_bsize == 0)
+                       continue;
+               if (mdtonly) {
+                       /* if only MDTs and DoM report MDT space,
+                        * otherwise only OST space */
+                       sfs->os_bavail = 0;
+                       sfs->os_blocks = 0;
+                       sfs->os_bfree = 0;
+                       sfs->os_granted = 0;
+                       mdtonly = false;
+               }
+               ost_sfs.os_bavail += ost_sfs.os_granted;
+               lod_statfs_sum(sfs, &ost_sfs, &bs);
+               LASSERTF(bs == ost_sfs.os_bsize, "%d != %d\n",
+                       (int)sfs->os_bsize, (int)ost_sfs.os_bsize);
+       }
+       lod_putref(lod, &lod->lod_ost_descs);
+       sfs->os_state |= OS_STATE_SUM;
+
+       /* a single successful statfs should be enough */
+       rc = 0;
+
+out:
+       RETURN(rc);
 }
 
 /**