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LU-9367 llite: restore ll_file_getstripe in ll_lov_setstripe
[fs/lustre-release.git] / lustre / lov / lov_pack.c
index 2972086..bdcf146 100644 (file)
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
- * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
- *
- * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
- * CA 95054 USA or visit www.sun.com if you need additional information or
- * have any questions.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
 /*
- * Copyright  2008 Sun Microsystems, Inc. All rights reserved
+ * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2015, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  */
 
 #define DEBUG_SUBSYSTEM S_LOV
-#ifndef __KERNEL__
-#include <liblustre.h>
-#endif
+
+#include <lustre/lustre_idl.h>
+#include <lustre/lustre_user.h>
 
 #include <lustre_net.h>
+#include <lustre_swab.h>
 #include <obd.h>
-#include <obd_lov.h>
 #include <obd_class.h>
 #include <obd_support.h>
-#include <lustre/lustre_user.h>
 
+#include "lov_cl_internal.h"
 #include "lov_internal.h"
 
-static void lov_dump_lmm_common(int level, void *lmmp)
+void lov_dump_lmm_common(int level, void *lmmp)
 {
-        struct lov_mds_md *lmm = lmmp;
-
-        CDEBUG(level, "objid "LPX64", magic 0x%08x, pattern %#x\n",
-               (__u64)le64_to_cpu(lmm->lmm_object_id),
-               le32_to_cpu(lmm->lmm_magic),
-               le32_to_cpu(lmm->lmm_pattern));
-        CDEBUG(level,"stripe_size %u, stripe_count %u\n",
-               le32_to_cpu(lmm->lmm_stripe_size),
-               le32_to_cpu(lmm->lmm_stripe_count));
+       struct lov_mds_md *lmm = lmmp;
+       struct ost_id   oi;
+
+       lmm_oi_le_to_cpu(&oi, &lmm->lmm_oi);
+       CDEBUG(level, "objid "DOSTID", magic 0x%08x, pattern %#x\n",
+              POSTID(&oi), le32_to_cpu(lmm->lmm_magic),
+              le32_to_cpu(lmm->lmm_pattern));
+       CDEBUG(level, "stripe_size %u, stripe_count %u, layout_gen %u\n",
+              le32_to_cpu(lmm->lmm_stripe_size),
+              le16_to_cpu(lmm->lmm_stripe_count),
+              le16_to_cpu(lmm->lmm_layout_gen));
 }
 
 static void lov_dump_lmm_objects(int level, struct lov_ost_data *lod,
                                  int stripe_count)
 {
-        int i;
-
-        if (stripe_count > LOV_V1_INSANE_STRIPE_COUNT) {
-                CDEBUG(level, "bad stripe_count %u > max_stripe_count %u\n",
-                       stripe_count, LOV_V1_INSANE_STRIPE_COUNT);
-        }
-
-        for (i = 0; i < stripe_count; ++i, ++lod) {
-                CDEBUG(level, "stripe %u idx %u subobj "LPX64"/"LPX64"\n", i,
-                       le32_to_cpu(lod->l_ost_idx),
-                       (__u64)le64_to_cpu(lod->l_object_gr),
-                       (__u64)le64_to_cpu(lod->l_object_id));
-        }
+       int i;
+
+       if (stripe_count > LOV_V1_INSANE_STRIPE_COUNT) {
+               CDEBUG(level, "bad stripe_count %u > max_stripe_count %u\n",
+                      stripe_count, LOV_V1_INSANE_STRIPE_COUNT);
+               return;
+       }
+
+       for (i = 0; i < stripe_count; ++i, ++lod) {
+               struct ost_id   oi;
+
+               ostid_le_to_cpu(&lod->l_ost_oi, &oi);
+               CDEBUG(level, "stripe %u idx %u subobj "DOSTID"\n", i,
+                      le32_to_cpu(lod->l_ost_idx), POSTID(&oi));
+       }
 }
 
 void lov_dump_lmm_v1(int level, struct lov_mds_md_v1 *lmm)
 {
         lov_dump_lmm_common(level, lmm);
         lov_dump_lmm_objects(level, lmm->lmm_objects,
-                             le32_to_cpu(lmm->lmm_stripe_count));
+                             le16_to_cpu(lmm->lmm_stripe_count));
 }
 
 void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
@@ -97,571 +97,363 @@ void lov_dump_lmm_v3(int level, struct lov_mds_md_v3 *lmm)
         lov_dump_lmm_common(level, lmm);
         CDEBUG(level,"pool_name "LOV_POOLNAMEF"\n", lmm->lmm_pool_name);
         lov_dump_lmm_objects(level, lmm->lmm_objects,
-                             le32_to_cpu(lmm->lmm_stripe_count));
+                             le16_to_cpu(lmm->lmm_stripe_count));
 }
 
 void lov_dump_lmm(int level, void *lmm)
 {
-        int magic;
-
-        magic = ((struct lov_mds_md_v1 *)(lmm))->lmm_magic;
-        switch (magic) {
-        case LOV_MAGIC_V1:
-                return lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)(lmm));
-        case LOV_MAGIC_V3:
-                return lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)(lmm));
-        default:
-                CERROR("Cannot recognize lmm_magic %x", magic);
-        }
-        return;
+       int magic;
+
+       magic = le32_to_cpu(((struct lov_mds_md *)lmm)->lmm_magic);
+       switch (magic) {
+       case LOV_MAGIC_V1:
+               lov_dump_lmm_v1(level, (struct lov_mds_md_v1 *)lmm);
+               break;
+       case LOV_MAGIC_V3:
+               lov_dump_lmm_v3(level, (struct lov_mds_md_v3 *)lmm);
+               break;
+       default:
+               CDEBUG(level, "unrecognized lmm_magic %x, assuming %x\n",
+                      magic, LOV_MAGIC_V1);
+               lov_dump_lmm_common(level, lmm);
+               break;
+       }
 }
 
-#define LMM_ASSERT(test)                                                \
-do {                                                                    \
-        if (!(test)) lov_dump_lmm(D_ERROR, lmm);                        \
-        LASSERT(test); /* so we know what assertion failed */           \
-} while(0)
-
-/* Pack LOV object metadata for disk storage.  It is packed in LE byte
- * order and is opaque to the networking layer.
+/**
+ * Pack LOV striping metadata for disk storage format (in little
+ * endian byte order).
  *
- * XXX In the future, this will be enhanced to get the EA size from the
- *     underlying OSC device(s) to get their EA sizes so we can stack
- *     LOVs properly.  For now lov_mds_md_size() just assumes one obd_id
- *     per stripe.
+ * This follows the getxattr() conventions. If \a buf_size is zero
+ * then return the size needed. If \a buf_size is too small then
+ * return -ERANGE. Otherwise return the size of the result.
  */
-int lov_packmd(struct obd_export *exp, struct lov_mds_md **lmmp,
-               struct lov_stripe_md *lsm)
+ssize_t lov_lsm_pack_v1v3(const struct lov_stripe_md *lsm, void *buf,
+                         size_t buf_size)
+{
+       struct lov_mds_md_v1 *lmmv1 = buf;
+       struct lov_mds_md_v3 *lmmv3 = buf;
+       struct lov_ost_data_v1 *lmm_objects;
+       size_t lmm_size;
+       unsigned int i;
+       ENTRY;
+
+       lmm_size = lov_mds_md_size(lsm->lsm_entries[0]->lsme_stripe_count,
+                                  lsm->lsm_magic);
+       if (buf_size == 0)
+               RETURN(lmm_size);
+
+       if (buf_size < lmm_size)
+               RETURN(-ERANGE);
+
+       /* lmmv1 and lmmv3 point to the same struct and have the
+        * same first fields
+        */
+       lmmv1->lmm_magic = cpu_to_le32(lsm->lsm_magic);
+       lmm_oi_cpu_to_le(&lmmv1->lmm_oi, &lsm->lsm_oi);
+       lmmv1->lmm_stripe_size = cpu_to_le32(
+                               lsm->lsm_entries[0]->lsme_stripe_size);
+       lmmv1->lmm_stripe_count = cpu_to_le16(
+                               lsm->lsm_entries[0]->lsme_stripe_count);
+       lmmv1->lmm_pattern = cpu_to_le32(lsm->lsm_entries[0]->lsme_pattern);
+       lmmv1->lmm_layout_gen = cpu_to_le16(lsm->lsm_layout_gen);
+
+       if (lsm->lsm_magic == LOV_MAGIC_V3) {
+               CLASSERT(sizeof(lsm->lsm_entries[0]->lsme_pool_name) ==
+                        sizeof(lmmv3->lmm_pool_name));
+               strlcpy(lmmv3->lmm_pool_name,
+                       lsm->lsm_entries[0]->lsme_pool_name,
+                       sizeof(lmmv3->lmm_pool_name));
+               lmm_objects = lmmv3->lmm_objects;
+       } else {
+               lmm_objects = lmmv1->lmm_objects;
+       }
+
+       if (lsm->lsm_is_released)
+               RETURN(lmm_size);
+
+       for (i = 0; i < lsm->lsm_entries[0]->lsme_stripe_count; i++) {
+               struct lov_oinfo *loi = lsm->lsm_entries[0]->lsme_oinfo[i];
+
+               ostid_cpu_to_le(&loi->loi_oi, &lmm_objects[i].l_ost_oi);
+               lmm_objects[i].l_ost_gen = cpu_to_le32(loi->loi_ost_gen);
+               lmm_objects[i].l_ost_idx = cpu_to_le32(loi->loi_ost_idx);
+       }
+
+       RETURN(lmm_size);
+}
+
+ssize_t lov_lsm_pack(const struct lov_stripe_md *lsm, void *buf,
+                    size_t buf_size)
 {
-        struct obd_device *obd = class_exp2obd(exp);
-        struct lov_obd *lov = &obd->u.lov;
-        struct lov_mds_md_v1 *lmmv1;
-        struct lov_mds_md_v3 *lmmv3;
-        int stripe_count;
-        struct lov_ost_data_v1 *lmm_objects;
-        int lmm_size, lmm_magic;
-        int i;
-        ENTRY;
-
-        if (lsm) {
-                lmm_magic = lsm->lsm_magic;
-
-                /* If we are just sizing the EA, limit the stripe count
-                 * to the actual number of OSTs in this filesystem. */
-                if (!lmmp) {
-                        stripe_count = lov_get_stripecnt(lov,
-                                                         lsm->lsm_stripe_count);
-                        lsm->lsm_stripe_count = stripe_count;
-                } else {
-                        stripe_count = lsm->lsm_stripe_count;
-                }
-        } else {
-                /* No needs to allocated more than LOV_MAX_STRIPE_COUNT.
-                 * Anyway, this is pretty inaccurate since ld_tgt_count now
-                 * represents max index and we should rely on the actual number
-                 * of OSTs instead */
-                stripe_count = min((__u32)LOV_MAX_STRIPE_COUNT,
-                                   lov->desc.ld_tgt_count);
-
-                if (lmmp && *lmmp)
-                        lmm_magic = le32_to_cpu((*lmmp)->lmm_magic);
-                else
-                        /* lsm == NULL and lmmp == NULL */
-                        lmm_magic = LOV_MAGIC;
-        }
-
-        if ((lmm_magic != LOV_MAGIC_V1) &&
-            (lmm_magic != LOV_MAGIC_V3)) {
-                CERROR("bad mem LOV MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
-                        lmm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
-                RETURN(-EINVAL);
-
-        }
-
-        /* XXX LOV STACKING call into osc for sizes */
-        lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
-
-        if (!lmmp)
-                RETURN(lmm_size);
-
-        if (*lmmp && !lsm) {
-                stripe_count = le32_to_cpu((*lmmp)->lmm_stripe_count);
-                lmm_size = lov_mds_md_size(stripe_count, lmm_magic);
-                OBD_FREE(*lmmp, lmm_size);
-                *lmmp = NULL;
-                RETURN(0);
-        }
-
-        if (!*lmmp) {
-                OBD_ALLOC(*lmmp, lmm_size);
-                if (!*lmmp)
-                        RETURN(-ENOMEM);
-        }
-
-        CDEBUG(D_INFO, "lov_packmd: LOV_MAGIC 0x%08X, lmm_size = %d \n",
-               lmm_magic, lmm_size);
-
-        lmmv1 = *lmmp;
-        lmmv3 = (struct lov_mds_md_v3 *)*lmmp;
-        if (lmm_magic == LOV_MAGIC_V3)
-                lmmv3->lmm_magic = cpu_to_le32(LOV_MAGIC_V3);
-        else
-                lmmv1->lmm_magic = cpu_to_le32(LOV_MAGIC_V1);
-
-        if (!lsm)
-                RETURN(lmm_size);
-
-        /* lmmv1 and lmmv3 point to the same struct and have the
-         * same first fields
-         */
-        lmmv1->lmm_object_id = cpu_to_le64(lsm->lsm_object_id);
-        lmmv1->lmm_object_gr = cpu_to_le64(lsm->lsm_object_gr);
-        lmmv1->lmm_stripe_size = cpu_to_le32(lsm->lsm_stripe_size);
-        lmmv1->lmm_stripe_count = cpu_to_le32(stripe_count);
-        lmmv1->lmm_pattern = cpu_to_le32(lsm->lsm_pattern);
-        if (lsm->lsm_magic == LOV_MAGIC_V3) {
-                strncpy(lmmv3->lmm_pool_name, lsm->lsm_pool_name,
-                        LOV_MAXPOOLNAME);
-                lmm_objects = lmmv3->lmm_objects;
-        } else {
-                lmm_objects = lmmv1->lmm_objects;
-        }
-
-        for (i = 0; i < stripe_count; i++) {
-                struct lov_oinfo *loi = lsm->lsm_oinfo[i];
-
-                /* XXX LOV STACKING call down to osc_packmd() to do packing */
-                LASSERTF(loi->loi_id, "lmm_oid "LPU64" stripe %u/%u idx %u\n",
-                         lmmv1->lmm_object_id, i, stripe_count, loi->loi_ost_idx);
-                lmm_objects[i].l_object_id = cpu_to_le64(loi->loi_id);
-                lmm_objects[i].l_object_gr = cpu_to_le64(loi->loi_gr);
-                lmm_objects[i].l_ost_gen = cpu_to_le32(loi->loi_ost_gen);
-                lmm_objects[i].l_ost_idx = cpu_to_le32(loi->loi_ost_idx);
-        }
-
-        RETURN(lmm_size);
+       struct lov_comp_md_v1 *lcmv1 = buf;
+       struct lov_comp_md_entry_v1 *lcme;
+       struct lov_ost_data_v1 *lmm_objects;
+       size_t lmm_size;
+       unsigned int entry;
+       unsigned int offset;
+       unsigned int size;
+       unsigned int i;
+       ENTRY;
+
+       if (lsm->lsm_magic == LOV_MAGIC_V1 || lsm->lsm_magic == LOV_MAGIC_V3)
+               return lov_lsm_pack_v1v3(lsm, buf, buf_size);
+
+       lmm_size = lov_comp_md_size(lsm);
+       if (buf_size == 0)
+               RETURN(lmm_size);
+
+       if (buf_size < lmm_size)
+               RETURN(-ERANGE);
+
+       lcmv1->lcm_magic = cpu_to_le32(lsm->lsm_magic);
+       lcmv1->lcm_size = cpu_to_le32(lmm_size);
+       lcmv1->lcm_layout_gen = cpu_to_le32(lsm->lsm_layout_gen);
+       lcmv1->lcm_entry_count = cpu_to_le16(lsm->lsm_entry_count);
+
+       offset = sizeof(*lcmv1) + sizeof(*lcme) * lsm->lsm_entry_count;
+
+       for (entry = 0; entry < lsm->lsm_entry_count; entry++) {
+               struct lov_stripe_md_entry *lsme;
+               struct lov_mds_md *lmm;
+               __u16 stripecnt;
+
+               lsme = lsm->lsm_entries[entry];
+               lcme = &lcmv1->lcm_entries[entry];
+
+               lcme->lcme_id = cpu_to_le32(lsme->lsme_id);
+               lcme->lcme_flags = cpu_to_le32(lsme->lsme_flags);
+               lcme->lcme_extent.e_start =
+                       cpu_to_le64(lsme->lsme_extent.e_start);
+               lcme->lcme_extent.e_end =
+                       cpu_to_le64(lsme->lsme_extent.e_end);
+               lcme->lcme_offset = cpu_to_le32(offset);
+
+               lmm = (struct lov_mds_md *)((char *)lcmv1 + offset);
+               lmm->lmm_magic = cpu_to_le32(lsme->lsme_magic);
+               /* lmm->lmm_oi not set */
+               lmm->lmm_pattern = cpu_to_le32(lsme->lsme_pattern);
+               lmm->lmm_stripe_size = cpu_to_le32(lsme->lsme_stripe_size);
+               lmm->lmm_stripe_count = cpu_to_le16(lsme->lsme_stripe_count);
+               lmm->lmm_layout_gen = cpu_to_le16(lsme->lsme_layout_gen);
+
+               if (lsme->lsme_magic == LOV_MAGIC_V3) {
+                       struct lov_mds_md_v3 *lmmv3 =
+                                               (struct lov_mds_md_v3 *)lmm;
+
+                       strlcpy(lmmv3->lmm_pool_name, lsme->lsme_pool_name,
+                               sizeof(lmmv3->lmm_pool_name));
+                       lmm_objects = lmmv3->lmm_objects;
+               } else {
+                       lmm_objects =
+                               ((struct lov_mds_md_v1 *)lmm)->lmm_objects;
+               }
+
+               if (lsme_inited(lsme) &&
+                   !(lsme->lsme_pattern & LOV_PATTERN_F_RELEASED))
+                       stripecnt = lsme->lsme_stripe_count;
+               else
+                       stripecnt = 0;
+
+               for (i = 0; i < stripecnt; i++) {
+                       struct lov_oinfo *loi = lsme->lsme_oinfo[i];
+
+                       ostid_cpu_to_le(&loi->loi_oi, &lmm_objects[i].l_ost_oi);
+                       lmm_objects[i].l_ost_gen =
+                                       cpu_to_le32(loi->loi_ost_gen);
+                       lmm_objects[i].l_ost_idx =
+                                       cpu_to_le32(loi->loi_ost_idx);
+               }
+
+               size = lov_mds_md_size(stripecnt, lsme->lsme_magic);
+               lcme->lcme_size = cpu_to_le32(size);
+               offset += size;
+       } /* for each layout component */
+
+       RETURN(lmm_size);
 }
 
 /* Find the max stripecount we should use */
-int lov_get_stripecnt(struct lov_obd *lov, __u32 stripe_count)
+__u16 lov_get_stripecnt(struct lov_obd *lov, __u32 magic, __u16 stripe_count)
 {
+        __u32 max_stripes = LOV_MAX_STRIPE_COUNT_OLD;
+
         if (!stripe_count)
                 stripe_count = lov->desc.ld_default_stripe_count;
         if (stripe_count > lov->desc.ld_active_tgt_count)
                 stripe_count = lov->desc.ld_active_tgt_count;
         if (!stripe_count)
                 stripe_count = 1;
-        /* for now, we limit the stripe count directly, when bug 4424 is
-         * fixed this needs to be somewhat dynamic based on whether ext3
-         * can handle larger EA sizes. */
-        if (stripe_count > LOV_MAX_STRIPE_COUNT)
-                stripe_count = LOV_MAX_STRIPE_COUNT;
-
-        return stripe_count;
-}
-
 
-static int lov_verify_lmm(void *lmm, int lmm_bytes, int *stripe_count)
-{
-        int rc;
-
-        if (lsm_op_find(le32_to_cpu(*(__u32 *)lmm)) == NULL) {
-                char *buffer;
-                int sz;
-
-                CERROR("bad disk LOV MAGIC: 0x%08X; dumping LMM (size=%d):\n",
-                       le32_to_cpu(*(__u32 *)lmm), lmm_bytes);
-                sz = lmm_bytes * 2 + 1;
-                OBD_ALLOC(buffer, sz);
-                if (buffer != NULL) {
-                        int i;
-
-                        for (i = 0; i < lmm_bytes; i++)
-                                sprintf(buffer+2*i, "%.2X", ((char *)lmm)[i]);
-                        buffer[sz] = '\0';
-                        CERROR("%s\n", buffer);
-                        OBD_FREE(buffer, sz);
-                }
-                return -EINVAL;
-        }
-        rc = lsm_op_find(le32_to_cpu(*(__u32 *)lmm))->lsm_lmm_verify(lmm,
-                                     lmm_bytes, stripe_count);
-        return rc;
-}
-
-int lov_alloc_memmd(struct lov_stripe_md **lsmp, int stripe_count,
-                      int pattern, int magic)
-{
-        int i, lsm_size;
-        ENTRY;
-
-        CDEBUG(D_INFO, "alloc lsm, stripe_count %d\n", stripe_count);
+        /* stripe count is based on whether ldiskfs can handle
+         * larger EA sizes */
+        if (lov->lov_ocd.ocd_connect_flags & OBD_CONNECT_MAX_EASIZE &&
+            lov->lov_ocd.ocd_max_easize)
+               max_stripes = lov_mds_md_max_stripe_count(
+                       lov->lov_ocd.ocd_max_easize, magic);
 
-        *lsmp = lsm_alloc_plain(stripe_count, &lsm_size);
-        if (!*lsmp) {
-                CERROR("can't allocate lsmp stripe_count %d\n", stripe_count);
-                RETURN(-ENOMEM);
-        }
+        if (stripe_count > max_stripes)
+                stripe_count = max_stripes;
 
-        cfs_spin_lock_init(&(*lsmp)->lsm_lock);
-        (*lsmp)->lsm_magic = magic;
-        (*lsmp)->lsm_stripe_count = stripe_count;
-        (*lsmp)->lsm_maxbytes = LUSTRE_STRIPE_MAXBYTES * stripe_count;
-        (*lsmp)->lsm_pattern = pattern;
-        (*lsmp)->lsm_pool_name[0] = '\0';
-        (*lsmp)->lsm_oinfo[0]->loi_ost_idx = ~0;
-
-        for (i = 0; i < stripe_count; i++)
-                loi_init((*lsmp)->lsm_oinfo[i]);
-
-        RETURN(lsm_size);
+        return stripe_count;
 }
 
-void lov_free_memmd(struct lov_stripe_md **lsmp)
+int lov_free_memmd(struct lov_stripe_md **lsmp)
 {
-        struct lov_stripe_md *lsm = *lsmp;
+       struct lov_stripe_md *lsm = *lsmp;
+       int refc;
 
-        LASSERT(lsm_op_find(lsm->lsm_magic) != NULL);
-        lsm_op_find(lsm->lsm_magic)->lsm_free(lsm);
+       *lsmp = NULL;
+       refc = atomic_dec_return(&lsm->lsm_refc);
+       LASSERT(refc >= 0);
+       if (refc == 0)
+               lsm_free(lsm);
 
-        *lsmp = NULL;
+       return refc;
 }
 
-
 /* Unpack LOV object metadata from disk storage.  It is packed in LE byte
  * order and is opaque to the networking layer.
  */
-int lov_unpackmd(struct obd_export *exp,  struct lov_stripe_md **lsmp,
-                 struct lov_mds_md *lmm, int lmm_bytes)
-{
-        struct obd_device *obd = class_exp2obd(exp);
-        struct lov_obd *lov = &obd->u.lov;
-        int rc = 0, stripe_count, lsm_size;
-        __u32 magic;
-        ENTRY;
-
-        /* If passed an MDS struct use values from there, otherwise defaults */
-        if (lmm) {
-                rc = lov_verify_lmm(lmm, lmm_bytes, &stripe_count);
-                if (rc)
-                        RETURN(rc);
-                magic = le32_to_cpu(lmm->lmm_magic);
-        } else {
-                stripe_count = lov_get_stripecnt(lov, 0);
-                magic = LOV_MAGIC;
-        }
-
-        /* If we aren't passed an lsmp struct, we just want the size */
-        if (!lsmp) {
-                /* XXX LOV STACKING call into osc for sizes */
-                LBUG();
-                RETURN(lov_stripe_md_size(stripe_count));
-        }
-        /* If we are passed an allocated struct but nothing to unpack, free */
-        if (*lsmp && !lmm) {
-                lov_free_memmd(lsmp);
-                RETURN(0);
-        }
-
-        lsm_size = lov_alloc_memmd(lsmp, stripe_count, LOV_PATTERN_RAID0,
-                                   magic);
-        if (lsm_size < 0)
-                RETURN(lsm_size);
-
-        /* If we are passed a pointer but nothing to unpack, we only alloc */
-        if (!lmm)
-                RETURN(lsm_size);
-
-        LASSERT(lsm_op_find(magic) != NULL);
-        rc = lsm_op_find(magic)->lsm_unpackmd(lov, *lsmp, lmm);
-        if (rc) {
-                lov_free_memmd(lsmp);
-                RETURN(rc);
-        }
-
-        RETURN(lsm_size);
-}
-
-static int __lov_setstripe(struct obd_export *exp, int max_lmm_size,
-                           struct lov_stripe_md **lsmp,
-                           struct lov_user_md *lump)
+struct lov_stripe_md *lov_unpackmd(struct lov_obd *lov, void *buf,
+                                  size_t buf_size)
 {
-        struct obd_device *obd = class_exp2obd(exp);
-        struct lov_obd *lov = &obd->u.lov;
-        char buffer[sizeof(struct lov_user_md_v3)];
-        struct lov_user_md_v3 *lumv3 = (struct lov_user_md_v3 *)&buffer[0];
-        struct lov_user_md_v1 *lumv1 = (struct lov_user_md_v1 *)&buffer[0];
-        int lmm_magic;
-        int stripe_count;
-        int rc;
-        ENTRY;
-
-        if (cfs_copy_from_user(lumv3, lump, sizeof(struct lov_user_md_v1)))
-                RETURN(-EFAULT);
-
-        lmm_magic = lumv1->lmm_magic;
-
-        if (lmm_magic == __swab32(LOV_USER_MAGIC_V1)) {
-                lustre_swab_lov_user_md_v1(lumv1);
-                lmm_magic = LOV_USER_MAGIC_V1;
-        } else if (lmm_magic == LOV_USER_MAGIC_V3) {
-                if (cfs_copy_from_user(lumv3, lump, sizeof(*lumv3)))
-                        RETURN(-EFAULT);
-        } else if (lmm_magic == __swab32(LOV_USER_MAGIC_V3)) {
-                if (cfs_copy_from_user(lumv3, lump, sizeof(*lumv3)))
-                        RETURN(-EFAULT);
-                lustre_swab_lov_user_md_v3(lumv3);
-                lmm_magic = LOV_USER_MAGIC_V3;
-        } else if (lmm_magic != LOV_USER_MAGIC_V1) {
-                CDEBUG(D_IOCTL,
-                       "bad userland LOV MAGIC: %#08x != %#08x nor %#08x\n",
-                       lmm_magic, LOV_USER_MAGIC_V1, LOV_USER_MAGIC_V3);
-                       RETURN(-EINVAL);
-        }
-
-        /* in the rest of the tests, as *lumv1 and lumv3 have the same
-         * fields, we use lumv1 to avoid code duplication */
-
-        if (lumv1->lmm_pattern == 0) {
-                lumv1->lmm_pattern = lov->desc.ld_pattern ?
-                        lov->desc.ld_pattern : LOV_PATTERN_RAID0;
-        }
-
-        if (lumv1->lmm_pattern != LOV_PATTERN_RAID0) {
-                CDEBUG(D_IOCTL, "bad userland stripe pattern: %#x\n",
-                       lumv1->lmm_pattern);
-                RETURN(-EINVAL);
-        }
-
-        /* 64kB is the largest common page size we see (ia64), and matches the
-         * check in lfs */
-        if (lumv1->lmm_stripe_size & (LOV_MIN_STRIPE_SIZE - 1)) {
-                CDEBUG(D_IOCTL, "stripe size %u not multiple of %u, fixing\n",
-                       lumv1->lmm_stripe_size, LOV_MIN_STRIPE_SIZE);
-                lumv1->lmm_stripe_size = LOV_MIN_STRIPE_SIZE;
-        }
-
-        if ((lumv1->lmm_stripe_offset >= lov->desc.ld_tgt_count) &&
-            (lumv1->lmm_stripe_offset !=
-             (typeof(lumv1->lmm_stripe_offset))(-1))) {
-                CDEBUG(D_IOCTL, "stripe offset %u > number of OSTs %u\n",
-                       lumv1->lmm_stripe_offset, lov->desc.ld_tgt_count);
-                RETURN(-EINVAL);
-        }
-        stripe_count = lov_get_stripecnt(lov, lumv1->lmm_stripe_count);
-
-        if (max_lmm_size) {
-                int max_stripes = (max_lmm_size -
-                                   lov_mds_md_size(0, lmm_magic)) /
-                                   sizeof(struct lov_ost_data_v1);
-                if (unlikely(max_stripes < stripe_count)) {
-                        CDEBUG(D_IOCTL, "stripe count reset from %d to %d\n",
-                               stripe_count, max_stripes);
-                        stripe_count = max_stripes;
-                }
-        }
-
-        if (lmm_magic == LOV_USER_MAGIC_V3) {
-                struct pool_desc *pool;
-
-                pool = lov_find_pool(lov, lumv3->lmm_pool_name);
-                if (pool != NULL) {
-                        if (lumv3->lmm_stripe_offset !=
-                            (typeof(lumv3->lmm_stripe_offset))(-1)) {
-                                rc = lov_check_index_in_pool(
-                                        lumv3->lmm_stripe_offset, pool);
-                                if (rc < 0) {
-                                        lov_pool_putref(pool);
-                                        RETURN(-EINVAL);
-                                }
-                        }
-
-                        if (stripe_count > pool_tgt_count(pool))
-                                stripe_count = pool_tgt_count(pool);
-
-                        lov_pool_putref(pool);
-                }
-        }
-
-        rc = lov_alloc_memmd(lsmp, stripe_count, lumv1->lmm_pattern, lmm_magic);
-
-        if (rc >= 0) {
-                (*lsmp)->lsm_oinfo[0]->loi_ost_idx = lumv1->lmm_stripe_offset;
-                (*lsmp)->lsm_stripe_size = lumv1->lmm_stripe_size;
-                if (lmm_magic == LOV_USER_MAGIC_V3)
-                        strncpy((*lsmp)->lsm_pool_name, lumv3->lmm_pool_name,
-                                LOV_MAXPOOLNAME);
-                rc = 0;
-        }
-
-        RETURN(rc);
-}
+       const struct lsm_operations *op;
+       struct lov_stripe_md *lsm;
+       u32 magic;
+       ENTRY;
 
-/* Configure object striping information on a new file.
- *
- * @lmmu is a pointer to a user struct with one or more of the fields set to
- * indicate the application preference: lmm_stripe_count, lmm_stripe_size,
- * lmm_stripe_offset, and lmm_stripe_pattern.  lmm_magic must be LOV_MAGIC.
- * @lsmp is a pointer to an in-core stripe MD that needs to be filled in.
- */
-int lov_setstripe(struct obd_export *exp, int max_lmm_size,
-                  struct lov_stripe_md **lsmp, struct lov_user_md *lump)
-{
-        int rc;
-        mm_segment_t seg;
+       if (buf_size < sizeof(magic))
+               RETURN(ERR_PTR(-EINVAL));
 
-        seg = get_fs();
-        set_fs(KERNEL_DS);
+       magic = le32_to_cpu(*(u32 *)buf);
+       op = lsm_op_find(magic);
+       if (op == NULL)
+               RETURN(ERR_PTR(-EINVAL));
 
-        rc = __lov_setstripe(exp, max_lmm_size, lsmp, lump);
-        set_fs(seg);
-        RETURN(rc);
-}
+       lsm = op->lsm_unpackmd(lov, buf, buf_size);
 
-int lov_setea(struct obd_export *exp, struct lov_stripe_md **lsmp,
-              struct lov_user_md *lump)
-{
-        int i;
-        int rc;
-        struct obd_export *oexp;
-        struct lov_obd *lov = &exp->exp_obd->u.lov;
-        obd_id last_id = 0;
-        struct lov_user_ost_data_v1 *lmm_objects;
-
-        ENTRY;
-
-        if (lump->lmm_magic == LOV_USER_MAGIC_V3)
-                lmm_objects = ((struct lov_user_md_v3 *)lump)->lmm_objects;
-        else
-                lmm_objects = lump->lmm_objects;
-
-        for (i = 0; i < lump->lmm_stripe_count; i++) {
-                __u32 len = sizeof(last_id);
-                oexp = lov->lov_tgts[lmm_objects[i].l_ost_idx]->ltd_exp;
-                rc = obd_get_info(oexp, sizeof(KEY_LAST_ID), KEY_LAST_ID,
-                                  &len, &last_id, NULL);
-                if (rc)
-                        RETURN(rc);
-                if (lmm_objects[i].l_object_id > last_id) {
-                        CERROR("Setting EA for object > than last id on "
-                               "ost idx %d "LPD64" > "LPD64" \n",
-                               lmm_objects[i].l_ost_idx,
-                               lmm_objects[i].l_object_id, last_id);
-                        RETURN(-EINVAL);
-                }
-        }
-
-        rc = lov_setstripe(exp, 0, lsmp, lump);
-        if (rc)
-                RETURN(rc);
-
-        for (i = 0; i < lump->lmm_stripe_count; i++) {
-                (*lsmp)->lsm_oinfo[i]->loi_ost_idx =
-                        lmm_objects[i].l_ost_idx;
-                (*lsmp)->lsm_oinfo[i]->loi_id = lmm_objects[i].l_object_id;
-                (*lsmp)->lsm_oinfo[i]->loi_gr = lmm_objects[i].l_object_gr;
-        }
-        RETURN(0);
+       RETURN(lsm);
 }
 
-
 /* Retrieve object striping information.
  *
  * @lump is a pointer to an in-core struct with lmm_ost_count indicating
  * the maximum number of OST indices which will fit in the user buffer.
  * lmm_magic must be LOV_USER_MAGIC.
+ *
+ * If @size > 0, User specified limited buffer size, usually the buffer is from
+ * ll_lov_setstripe(), and the buffer can only hold basic layout template info.
  */
-int lov_getstripe(struct obd_export *exp, struct lov_stripe_md *lsm,
-                  struct lov_user_md *lump)
+int lov_getstripe(const struct lu_env *env, struct lov_object *obj,
+                 struct lov_stripe_md *lsm, struct lov_user_md __user *lump,
+                 size_t size)
 {
-        /*
-         * XXX huge struct allocated on stack.
-         */
-        /* we use lov_user_md_v3 because it is larger than lov_user_md_v1 */
-        struct lov_user_md_v3 lum;
-        struct lov_mds_md *lmmk = NULL;
-        int rc, lmm_size;
-        int lum_size;
-        mm_segment_t seg;
-        ENTRY;
-
-        if (!lsm)
-                RETURN(-ENODATA);
-
-        /*
-         * "Switch to kernel segment" to allow copying from kernel space by
-         * copy_{to,from}_user().
-         */
-        seg = get_fs();
-        set_fs(KERNEL_DS);
-
-        /* we only need the header part from user space to get lmm_magic and
-         * lmm_stripe_count, (the header part is common to v1 and v3) */
-        lum_size = sizeof(struct lov_user_md_v1);
-        if (cfs_copy_from_user(&lum, lump, lum_size))
-                GOTO(out_set, rc = -EFAULT);
-        else if ((lum.lmm_magic != LOV_USER_MAGIC) &&
-                 (lum.lmm_magic != LOV_USER_MAGIC_V3))
-                GOTO(out_set, rc = -EINVAL);
-
-        if (lum.lmm_stripe_count &&
-            (lum.lmm_stripe_count < lsm->lsm_stripe_count)) {
-                /* Return right size of stripe to user */
-                lum.lmm_stripe_count = lsm->lsm_stripe_count;
-                rc = cfs_copy_to_user(lump, &lum, lum_size);
-                GOTO(out_set, rc = -EOVERFLOW);
-        }
-        rc = lov_packmd(exp, &lmmk, lsm);
-        if (rc < 0)
-                GOTO(out_set, rc);
-        lmm_size = rc;
-        rc = 0;
-
-        /* FIXME: Bug 1185 - copy fields properly when structs change */
-        /* struct lov_user_md_v3 and struct lov_mds_md_v3 must be the same */
-        CLASSERT(sizeof(lum) == sizeof(struct lov_mds_md_v3));
-        CLASSERT(sizeof lum.lmm_objects[0] == sizeof lmmk->lmm_objects[0]);
-
-        if ((cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) &&
-            ((lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V1)) ||
-            (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V3)))) {
-                lustre_swab_lov_mds_md(lmmk);
-                lustre_swab_lov_user_md_objects(
-                                (struct lov_user_ost_data*)lmmk->lmm_objects,
-                                lmmk->lmm_stripe_count);
-        }
-        if (lum.lmm_magic == LOV_USER_MAGIC) {
-                /* User request for v1, we need skip lmm_pool_name */
-                if (lmmk->lmm_magic == LOV_MAGIC_V3) {
-                        memmove((char*)(&lmmk->lmm_stripe_count) +
-                                sizeof(lmmk->lmm_stripe_count),
-                                ((struct lov_mds_md_v3*)lmmk)->lmm_objects,
-                                lmmk->lmm_stripe_count *
-                                sizeof(struct lov_ost_data_v1));
-                        lmm_size -= LOV_MAXPOOLNAME;
-                }
-        } else {
-                /* if v3 we just have to update the lum_size */
-                lum_size = sizeof(struct lov_user_md_v3);
-        }
-
-        /* User wasn't expecting this many OST entries */
-        if (lum.lmm_stripe_count == 0)
-                lmm_size = lum_size;
-        else if (lum.lmm_stripe_count < lmmk->lmm_stripe_count)
-                GOTO(out_set, rc = -EOVERFLOW);
-        /*
-         * Have a difference between lov_mds_md & lov_user_md.
-         * So we have to re-order the data before copy to user.
-         */
-        lum.lmm_stripe_count = lmmk->lmm_stripe_count;
-        ((struct lov_user_md*)lmmk)->lmm_stripe_offset = 0;
-        ((struct lov_user_md*)lmmk)->lmm_stripe_count = lum.lmm_stripe_count;
-        if (cfs_copy_to_user(lump, lmmk, lmm_size))
-                rc = -EFAULT;
-
-        obd_free_diskmd(exp, &lmmk);
-out_set:
-        set_fs(seg);
-        RETURN(rc);
+       /* we use lov_user_md_v3 because it is larger than lov_user_md_v1 */
+       struct lov_mds_md *lmmk, *lmm;
+       struct lov_user_md_v1 lum;
+       size_t  lmmk_size;
+       ssize_t lmm_size, lum_size = 0;
+       static bool printed;
+       int     rc = 0;
+       ENTRY;
+
+       if (lsm->lsm_magic != LOV_MAGIC_V1 && lsm->lsm_magic != LOV_MAGIC_V3 &&
+           lsm->lsm_magic != LOV_MAGIC_COMP_V1) {
+               CERROR("bad LSM MAGIC: 0x%08X != 0x%08X nor 0x%08X\n",
+                      lsm->lsm_magic, LOV_MAGIC_V1, LOV_MAGIC_V3);
+               GOTO(out, rc = -EIO);
+       }
+
+       if (!printed) {
+               LCONSOLE_WARN("%s: using old ioctl(LL_IOC_LOV_GETSTRIPE) on "
+                             DFID", use llapi_layout_get_by_path()\n",
+                             current->comm,
+                             PFID(&obj->lo_cl.co_lu.lo_header->loh_fid));
+               printed = true;
+       }
+
+       lmmk_size = lov_comp_md_size(lsm);
+
+       OBD_ALLOC_LARGE(lmmk, lmmk_size);
+       if (lmmk == NULL)
+               GOTO(out, rc = -ENOMEM);
+
+       lmm_size = lov_lsm_pack(lsm, lmmk, lmmk_size);
+       if (lmm_size < 0)
+               GOTO(out_free, rc = lmm_size);
+
+       if (cpu_to_le32(LOV_MAGIC) != LOV_MAGIC) {
+               if (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V1) ||
+                   lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_V3)) {
+                       lustre_swab_lov_mds_md(lmmk);
+                       lustre_swab_lov_user_md_objects(
+                               (struct lov_user_ost_data *)lmmk->lmm_objects,
+                               lmmk->lmm_stripe_count);
+               } else if (lmmk->lmm_magic == cpu_to_le32(LOV_MAGIC_COMP_V1)) {
+                       lustre_swab_lov_comp_md_v1(
+                                       (struct lov_comp_md_v1 *)lmmk);
+               }
+       }
+
+       /* Legacy appication passes limited buffer, we need to figure out
+        * the user buffer size by the passed in lmm_stripe_count. */
+       if (copy_from_user(&lum, lump, sizeof(struct lov_user_md_v1)))
+               GOTO(out_free, rc = -EFAULT);
+
+       if (lum.lmm_magic == LOV_USER_MAGIC_V1 ||
+           lum.lmm_magic == LOV_USER_MAGIC_V3)
+               lum_size = lov_user_md_size(lum.lmm_stripe_count,
+                                           lum.lmm_magic);
+
+       if (lum_size != 0) {
+               struct lov_mds_md *comp_md = lmmk;
+
+               /* Legacy app (ADIO for instance) treats the layout as V1/V3
+                * blindly, we'd return a reasonable V1/V3 for them. */
+               if (lmmk->lmm_magic == LOV_MAGIC_COMP_V1) {
+                       struct lov_comp_md_v1 *comp_v1;
+                       struct cl_object *cl_obj;
+                       struct cl_attr attr;
+                       int i;
+
+                       attr.cat_size = 0;
+                       cl_obj = cl_object_top(&obj->lo_cl);
+                       cl_object_attr_get(env, cl_obj, &attr);
+
+                       /* return the last instantiated component if file size
+                        * is non-zero, otherwise, return the last component.*/
+                       comp_v1 = (struct lov_comp_md_v1 *)lmmk;
+                       i = attr.cat_size == 0 ? comp_v1->lcm_entry_count : 0;
+                       for (; i < comp_v1->lcm_entry_count; i++) {
+                               if (!(comp_v1->lcm_entries[i].lcme_flags &
+                                               LCME_FL_INIT))
+                                       break;
+                       }
+                       if (i > 0)
+                               i--;
+                       comp_md = (struct lov_mds_md *)((char *)comp_v1 +
+                                       comp_v1->lcm_entries[i].lcme_offset);
+               }
+
+               lmm = comp_md;
+               lmm_size = lum_size;
+       } else {
+               lmm = lmmk;
+               lmm_size = lmmk_size;
+       }
+       /**
+        * User specified limited buffer size, usually the buffer is
+        * from ll_lov_setstripe(), and the buffer can only hold basic
+        * layout template info.
+        */
+       if (size == 0 || size > lmm_size)
+               size = lmm_size;
+       if (copy_to_user(lump, lmm, size))
+               GOTO(out_free, rc = -EFAULT);
+
+out_free:
+       OBD_FREE_LARGE(lmmk, lmmk_size);
+out:
+       RETURN(rc);
 }