+/**
+ * We calculate on which OST the mapping will end. If the length of mapping
+ * is greater than (stripe_size * stripe_count) then the last_stripe will
+ * will be one just before start_stripe. Else we check if the mapping
+ * intersects each OST and find last_stripe.
+ * This function returns the last_stripe and also sets the stripe_count
+ * over which the mapping is spread
+ *
+ * \param lsm [in] striping information for the file
+ * \param fm_start [in] logical start of mapping
+ * \param fm_end [in] logical end of mapping
+ * \param start_stripe [in] starting stripe of the mapping
+ * \param stripe_count [out] the number of stripes across which to map is
+ * returned
+ *
+ * \retval last_stripe return the last stripe of the mapping
+ */
+static int fiemap_calc_last_stripe(struct lov_stripe_md *lsm,
+ loff_t fm_start, loff_t fm_end,
+ int start_stripe, int *stripe_count)
+{
+ int last_stripe;
+ loff_t obd_start;
+ loff_t obd_end;
+ int i, j;
+
+ if (fm_end - fm_start > lsm->lsm_stripe_size * lsm->lsm_stripe_count) {
+ last_stripe = (start_stripe < 1 ? lsm->lsm_stripe_count - 1 :
+ start_stripe - 1);
+ *stripe_count = lsm->lsm_stripe_count;
+ } else {
+ for (j = 0, i = start_stripe; j < lsm->lsm_stripe_count;
+ i = (i + 1) % lsm->lsm_stripe_count, j++) {
+ if ((lov_stripe_intersects(lsm, i, fm_start, fm_end,
+ &obd_start, &obd_end)) == 0)
+ break;
+ }
+ *stripe_count = j;
+ last_stripe = (start_stripe + j - 1) % lsm->lsm_stripe_count;
+ }
+
+ return last_stripe;
+}
+
+/**
+ * Set fe_device and copy extents from local buffer into main return buffer.
+ *
+ * \param fiemap [out] fiemap to hold all extents
+ * \param lcl_fm_ext [in] array of fiemap extents get from OSC layer
+ * \param ost_index [in] OST index to be written into the fm_device
+ * field for each extent
+ * \param ext_count [in] number of extents to be copied
+ * \param current_extent [in] where to start copying in the extent array
+ */
+static void fiemap_prepare_and_copy_exts(struct fiemap *fiemap,
+ struct ll_fiemap_extent *lcl_fm_ext,
+ int ost_index, unsigned int ext_count,
+ int current_extent)
+{
+ char *to;
+ unsigned int ext;
+
+ for (ext = 0; ext < ext_count; ext++) {
+ lcl_fm_ext[ext].fe_device = ost_index;
+ lcl_fm_ext[ext].fe_flags |= FIEMAP_EXTENT_NET;
+ }
+
+ /* Copy fm_extent's from fm_local to return buffer */
+ to = (char *)fiemap + fiemap_count_to_size(current_extent);
+ memcpy(to, lcl_fm_ext, ext_count * sizeof(struct ll_fiemap_extent));
+}
+
+#define FIEMAP_BUFFER_SIZE 4096
+
+/**
+ * Non-zero fe_logical indicates that this is a continuation FIEMAP
+ * call. The local end offset and the device are sent in the first
+ * fm_extent. This function calculates the stripe number from the index.
+ * This function returns a stripe_no on which mapping is to be restarted.
+ *
+ * This function returns fm_end_offset which is the in-OST offset at which
+ * mapping should be restarted. If fm_end_offset=0 is returned then caller
+ * will re-calculate proper offset in next stripe.
+ * Note that the first extent is passed to lov_get_info via the value field.
+ *
+ * \param fiemap [in] fiemap request header
+ * \param lsm [in] striping information for the file
+ * \param fm_start [in] logical start of mapping
+ * \param fm_end [in] logical end of mapping
+ * \param start_stripe [out] starting stripe will be returned in this
+ */
+static loff_t fiemap_calc_fm_end_offset(struct fiemap *fiemap,
+ struct lov_stripe_md *lsm,
+ loff_t fm_start, loff_t fm_end,
+ int *start_stripe)
+{
+ loff_t local_end = fiemap->fm_extents[0].fe_logical;
+ loff_t lun_start;
+ loff_t lun_end;
+ loff_t fm_end_offset;
+ int stripe_no = -1;
+ int i;
+
+ if (fiemap->fm_extent_count == 0 ||
+ fiemap->fm_extents[0].fe_logical == 0)
+ return 0;
+
+ /* Find out stripe_no from ost_index saved in the fe_device */
+ for (i = 0; i < lsm->lsm_stripe_count; i++) {
+ struct lov_oinfo *oinfo = lsm->lsm_oinfo[i];
+
+ if (lov_oinfo_is_dummy(oinfo))
+ continue;
+
+ if (oinfo->loi_ost_idx == fiemap->fm_extents[0].fe_device) {
+ stripe_no = i;
+ break;
+ }
+ }
+
+ if (stripe_no == -1)
+ return -EINVAL;
+
+ /* If we have finished mapping on previous device, shift logical
+ * offset to start of next device */
+ if (lov_stripe_intersects(lsm, stripe_no, fm_start, fm_end,
+ &lun_start, &lun_end) != 0 &&
+ local_end < lun_end) {
+ fm_end_offset = local_end;
+ *start_stripe = stripe_no;
+ } else {
+ /* This is a special value to indicate that caller should
+ * calculate offset in next stripe. */
+ fm_end_offset = 0;
+ *start_stripe = (stripe_no + 1) % lsm->lsm_stripe_count;
+ }
+
+ return fm_end_offset;
+}
+
+/**
+ * Break down the FIEMAP request and send appropriate calls to individual OSTs.
+ * This also handles the restarting of FIEMAP calls in case mapping overflows
+ * the available number of extents in single call.
+ *
+ * \param env [in] lustre environment
+ * \param obj [in] file object
+ * \param fmkey [in] fiemap request header and other info
+ * \param fiemap [out] fiemap buffer holding retrived map extents
+ * \param buflen [in/out] max buffer length of @fiemap, when iterate
+ * each OST, it is used to limit max map needed
+ * \retval 0 success
+ * \retval < 0 error
+ */
+static int lov_object_fiemap(const struct lu_env *env, struct cl_object *obj,
+ struct ll_fiemap_info_key *fmkey,
+ struct fiemap *fiemap, size_t *buflen)
+{
+ struct lov_stripe_md *lsm;
+ struct cl_object *subobj = NULL;
+ struct lov_obd *lov = lu2lov_dev(obj->co_lu.lo_dev)->ld_lov;
+ struct fiemap *fm_local = NULL;
+ struct ll_fiemap_extent *lcl_fm_ext;
+ loff_t fm_start;
+ loff_t fm_end;
+ loff_t fm_length;
+ loff_t fm_end_offset;
+ int count_local;
+ int ost_index = 0;
+ int start_stripe;
+ int current_extent = 0;
+ int rc = 0;
+ int last_stripe;
+ int cur_stripe = 0;
+ int cur_stripe_wrap = 0;
+ int stripe_count;
+ unsigned int buffer_size = FIEMAP_BUFFER_SIZE;
+ /* Whether have we collected enough extents */
+ bool enough = false;
+ /* EOF for object */
+ bool ost_eof = false;
+ /* done with required mapping for this OST? */
+ bool ost_done = false;
+ ENTRY;
+
+ lsm = lov_lsm_addref(cl2lov(obj));
+ if (lsm == NULL)
+ RETURN(-ENODATA);
+
+ /**
+ * If the stripe_count > 1 and the application does not understand
+ * DEVICE_ORDER flag, it cannot interpret the extents correctly.
+ */
+ if (lsm->lsm_stripe_count > 1 && !(fiemap->fm_flags &
+ FIEMAP_FLAG_DEVICE_ORDER))
+ GOTO(out, rc = -ENOTSUPP);
+
+ if (lsm_is_released(lsm)) {
+ if (fiemap->fm_start < fmkey->oa.o_size) {
+ /**
+ * released file, return a minimal FIEMAP if
+ * request fits in file-size.
+ */
+ fiemap->fm_mapped_extents = 1;
+ fiemap->fm_extents[0].fe_logical = fiemap->fm_start;
+ if (fiemap->fm_start + fiemap->fm_length <
+ fmkey->oa.o_size)
+ fiemap->fm_extents[0].fe_length =
+ fiemap->fm_length;
+ else
+ fiemap->fm_extents[0].fe_length =
+ fmkey->oa.o_size - fiemap->fm_start;
+ fiemap->fm_extents[0].fe_flags |=
+ FIEMAP_EXTENT_UNKNOWN | FIEMAP_EXTENT_LAST;
+ }
+ GOTO(out, rc = 0);
+ }
+
+ if (fiemap_count_to_size(fiemap->fm_extent_count) < buffer_size)
+ buffer_size = fiemap_count_to_size(fiemap->fm_extent_count);
+
+ OBD_ALLOC_LARGE(fm_local, buffer_size);
+ if (fm_local == NULL)
+ GOTO(out, rc = -ENOMEM);
+ lcl_fm_ext = &fm_local->fm_extents[0];
+ count_local = fiemap_size_to_count(buffer_size);
+
+ fm_start = fiemap->fm_start;
+ fm_length = fiemap->fm_length;
+ /* Calculate start stripe, last stripe and length of mapping */
+ start_stripe = lov_stripe_number(lsm, fm_start);
+ fm_end = (fm_length == ~0ULL) ? fmkey->oa.o_size :
+ fm_start + fm_length - 1;
+ /* If fm_length != ~0ULL but fm_start_fm_length-1 exceeds file size */
+ if (fm_end > fmkey->oa.o_size)
+ fm_end = fmkey->oa.o_size;
+
+ last_stripe = fiemap_calc_last_stripe(lsm, fm_start, fm_end,
+ start_stripe, &stripe_count);
+ fm_end_offset = fiemap_calc_fm_end_offset(fiemap, lsm, fm_start, fm_end,
+ &start_stripe);
+ if (fm_end_offset == -EINVAL)
+ GOTO(out, rc = -EINVAL);
+
+ /**
+ * Requested extent count exceeds the fiemap buffer size, shrink our
+ * ambition.
+ */
+ if (fiemap_count_to_size(fiemap->fm_extent_count) > *buflen)
+ fiemap->fm_extent_count = fiemap_size_to_count(*buflen);
+ if (fiemap->fm_extent_count == 0)
+ count_local = 0;
+
+ /* Check each stripe */
+ for (cur_stripe = start_stripe; stripe_count > 0;
+ --stripe_count,
+ cur_stripe = (cur_stripe + 1) % lsm->lsm_stripe_count) {
+ loff_t req_fm_len; /* Stores length of required mapping */
+ loff_t len_mapped_single_call;
+ loff_t lun_start;
+ loff_t lun_end;
+ loff_t obd_object_end;
+ unsigned int ext_count;
+
+ cur_stripe_wrap = cur_stripe;
+
+ /* Find out range of mapping on this stripe */
+ if ((lov_stripe_intersects(lsm, cur_stripe, fm_start, fm_end,
+ &lun_start, &obd_object_end)) == 0)
+ continue;
+
+ if (lov_oinfo_is_dummy(lsm->lsm_oinfo[cur_stripe]))
+ GOTO(out, rc = -EIO);
+
+ /* If this is a continuation FIEMAP call and we are on
+ * starting stripe then lun_start needs to be set to
+ * fm_end_offset */
+ if (fm_end_offset != 0 && cur_stripe == start_stripe)
+ lun_start = fm_end_offset;
+
+ if (fm_length != ~0ULL) {
+ /* Handle fm_start + fm_length overflow */
+ if (fm_start + fm_length < fm_start)
+ fm_length = ~0ULL - fm_start;
+ lun_end = lov_size_to_stripe(lsm, fm_start + fm_length,
+ cur_stripe);
+ } else {
+ lun_end = ~0ULL;
+ }
+
+ if (lun_start == lun_end)
+ continue;
+
+ req_fm_len = obd_object_end - lun_start;
+ fm_local->fm_length = 0;
+ len_mapped_single_call = 0;
+
+ /* find lobsub object */
+ subobj = lov_find_subobj(env, cl2lov(obj), lsm,
+ cur_stripe);
+ if (IS_ERR(subobj))
+ GOTO(out, rc = PTR_ERR(subobj));
+ /* If the output buffer is very large and the objects have many
+ * extents we may need to loop on a single OST repeatedly */
+ ost_eof = false;
+ ost_done = false;
+ do {
+ if (fiemap->fm_extent_count > 0) {
+ /* Don't get too many extents. */
+ if (current_extent + count_local >
+ fiemap->fm_extent_count)
+ count_local = fiemap->fm_extent_count -
+ current_extent;
+ }
+
+ lun_start += len_mapped_single_call;
+ fm_local->fm_length = req_fm_len -
+ len_mapped_single_call;
+ req_fm_len = fm_local->fm_length;
+ fm_local->fm_extent_count = enough ? 1 : count_local;
+ fm_local->fm_mapped_extents = 0;
+ fm_local->fm_flags = fiemap->fm_flags;
+
+ ost_index = lsm->lsm_oinfo[cur_stripe]->loi_ost_idx;
+
+ if (ost_index < 0 ||
+ ost_index >= lov->desc.ld_tgt_count)
+ GOTO(obj_put, rc = -EINVAL);
+ /* If OST is inactive, return extent with UNKNOWN
+ * flag. */
+ if (!lov->lov_tgts[ost_index]->ltd_active) {
+ fm_local->fm_flags |= FIEMAP_EXTENT_LAST;
+ fm_local->fm_mapped_extents = 1;
+
+ lcl_fm_ext[0].fe_logical = lun_start;
+ lcl_fm_ext[0].fe_length = obd_object_end -
+ lun_start;
+ lcl_fm_ext[0].fe_flags |= FIEMAP_EXTENT_UNKNOWN;
+
+ goto inactive_tgt;
+ }
+
+ fm_local->fm_start = lun_start;
+ fm_local->fm_flags &= ~FIEMAP_FLAG_DEVICE_ORDER;
+ memcpy(&fmkey->fiemap, fm_local, sizeof(*fm_local));
+ *buflen = fiemap_count_to_size(
+ fm_local->fm_extent_count);
+
+ rc = cl_object_fiemap(env, subobj, fmkey, fm_local,
+ buflen);
+ if (rc != 0)
+ GOTO(obj_put, rc);
+inactive_tgt:
+ ext_count = fm_local->fm_mapped_extents;
+ if (ext_count == 0) {
+ ost_done = true;
+ /* If last stripe has hold at the end,
+ * we need to return */
+ if (cur_stripe_wrap == last_stripe) {
+ fiemap->fm_mapped_extents = 0;
+ goto finish;
+ }
+ break;
+ } else if (enough) {
+ /*
+ * We've collected enough extents and there are
+ * more extents after it.
+ */
+ goto finish;
+ }
+
+ /* If we just need num of extents, got to next device */
+ if (fiemap->fm_extent_count == 0) {
+ current_extent += ext_count;
+ break;
+ }
+
+ /* prepare to copy retrived map extents */
+ len_mapped_single_call =
+ lcl_fm_ext[ext_count - 1].fe_logical -
+ lun_start + lcl_fm_ext[ext_count - 1].fe_length;
+
+ /* Have we finished mapping on this device? */
+ if (req_fm_len <= len_mapped_single_call)
+ ost_done = true;
+
+ /* Clear the EXTENT_LAST flag which can be present on
+ * the last extent */
+ if (lcl_fm_ext[ext_count - 1].fe_flags &
+ FIEMAP_EXTENT_LAST)
+ lcl_fm_ext[ext_count - 1].fe_flags &=
+ ~FIEMAP_EXTENT_LAST;
+ if (lov_stripe_size(lsm,
+ lcl_fm_ext[ext_count - 1].fe_logical +
+ lcl_fm_ext[ext_count - 1].fe_length,
+ cur_stripe) >= fmkey->oa.o_size)
+ ost_eof = true;
+
+ fiemap_prepare_and_copy_exts(fiemap, lcl_fm_ext,
+ ost_index, ext_count,
+ current_extent);
+ current_extent += ext_count;
+
+ /* Ran out of available extents? */
+ if (current_extent >= fiemap->fm_extent_count)
+ enough = true;
+ } while (!ost_done && !ost_eof);
+
+ cl_object_put(env, subobj);
+ subobj = NULL;
+
+ if (cur_stripe_wrap == last_stripe)
+ goto finish;
+ } /* for each stripe */
+finish:
+ /* Indicate that we are returning device offsets unless file just has
+ * single stripe */
+ if (lsm->lsm_stripe_count > 1)
+ fiemap->fm_flags |= FIEMAP_FLAG_DEVICE_ORDER;
+
+ if (fiemap->fm_extent_count == 0)
+ goto skip_last_device_calc;
+
+ /* Check if we have reached the last stripe and whether mapping for that
+ * stripe is done. */
+ if ((cur_stripe_wrap == last_stripe) && (ost_done || ost_eof))
+ fiemap->fm_extents[current_extent - 1].fe_flags |=
+ FIEMAP_EXTENT_LAST;
+skip_last_device_calc:
+ fiemap->fm_mapped_extents = current_extent;
+obj_put:
+ if (subobj != NULL)
+ cl_object_put(env, subobj);
+out:
+ if (fm_local != NULL)
+ OBD_FREE_LARGE(fm_local, buffer_size);
+ lov_lsm_put(obj, lsm);
+ RETURN(rc);
+}
+
+static int lov_dispatch_obd_info_get(const struct lu_env *env,
+ struct cl_object *obj,
+ struct obd_info *oinfo,
+ struct ptlrpc_request_set *set)
+{
+ struct cl_object *subobj = NULL;
+ struct lov_obd *lov = lu2lov_dev(obj->co_lu.lo_dev)->ld_lov;
+ struct lov_request_set *lovset;
+ struct list_head *pos;
+ struct lov_request *req;
+ int rc;
+ int rc2;
+ ENTRY;
+
+ rc = lov_prep_getattr_set(lov2obd(lov)->obd_self_export, oinfo,
+ &lovset);
+ if (rc != 0)
+ RETURN(rc);
+
+ CDEBUG(D_INFO, "objid "DOSTID": %ux%u byte stripes.\n",
+ POSTID(&oinfo->oi_md->lsm_oi),
+ oinfo->oi_md->lsm_stripe_count,
+ oinfo->oi_md->lsm_stripe_size);
+
+ list_for_each(pos, &lovset->set_list) {
+ req = list_entry(pos, struct lov_request, rq_link);
+
+ CDEBUG(D_INFO, "objid "DOSTID"[%d] has subobj "DOSTID" at idx"
+ "%u\n", POSTID(&oinfo->oi_oa->o_oi), req->rq_stripe,
+ POSTID(&req->rq_oi.oi_oa->o_oi), req->rq_idx);
+ subobj = lov_find_subobj(env, cl2lov(obj), oinfo->oi_md,
+ req->rq_stripe);
+ if (IS_ERR(subobj))
+ GOTO(errout, rc = PTR_ERR(subobj));
+
+ rc = cl_object_obd_info_get(env, subobj, &req->rq_oi, set);
+ cl_object_put(env, subobj);
+ if (rc != 0) {
+ CERROR("%s: getattr objid "DOSTID" subobj"
+ DOSTID" on OST idx %d: rc = %d\n",
+ lov2obd(lov)->obd_name,
+ POSTID(&oinfo->oi_oa->o_oi),
+ POSTID(&req->rq_oi.oi_oa->o_oi),
+ req->rq_idx, rc);
+ GOTO(errout, rc);
+ }
+ }
+
+ if (!list_empty(&set->set_requests)) {
+ LASSERT(rc == 0);
+ LASSERT(set->set_interpret == NULL);
+ set->set_interpret = lov_getattr_interpret;
+ set->set_arg = lovset;
+ GOTO(out, rc);
+ }
+errout:
+ if (rc)
+ atomic_set(&lovset->set_completes, 0);
+ rc2 = lov_fini_getattr_set(lovset);
+ rc = rc != 0 ? rc : rc2;
+out:
+ RETURN(rc);
+}
+
+static int lov_object_data_version(const struct lu_env *env,
+ struct cl_object *obj, __u64 *data_version,
+ int flags)
+{
+ struct ptlrpc_request_set *set;
+ struct obd_info oinfo = { { { 0 } } };
+ struct obdo *obdo = NULL;
+ struct lov_stripe_md *lsm;
+ int rc;
+ ENTRY;
+
+ lsm = lov_lsm_addref(cl2lov(obj));
+ if (!lsm_has_objects(lsm)) {
+ /* If no stripe, we consider version is 0. */
+ *data_version = 0;
+ GOTO(out, rc = 0);
+ }
+
+ OBD_ALLOC_PTR(obdo);
+ if (obdo == NULL)
+ GOTO(out, rc = -ENOMEM);
+
+ oinfo.oi_md = lsm;
+ oinfo.oi_oa = obdo;
+ obdo->o_oi = lsm->lsm_oi;
+ obdo->o_mode = S_IFREG;
+ obdo->o_valid = OBD_MD_FLID | OBD_MD_FLGROUP | OBD_MD_FLTYPE;
+ if (flags & (LL_DV_RD_FLUSH | LL_DV_WR_FLUSH)) {
+ obdo->o_valid |= OBD_MD_FLFLAGS;
+ obdo->o_flags |= OBD_FL_SRVLOCK;
+ if (flags & LL_DV_WR_FLUSH)
+ obdo->o_flags |= OBD_FL_FLUSH;
+ }
+
+ set = ptlrpc_prep_set();
+ if (set == NULL)
+ GOTO(out_obdo, rc = -ENOMEM);
+
+ rc = lov_dispatch_obd_info_get(env, obj, &oinfo, set);
+ if (rc == 0)
+ rc = ptlrpc_set_wait(set);
+ ptlrpc_set_destroy(set);
+ if (rc == 0) {
+ oinfo.oi_oa->o_valid &= OBD_MD_FLDATAVERSION | OBD_MD_FLFLAGS;
+ if (flags & LL_DV_WR_FLUSH &&
+ !(oinfo.oi_oa->o_valid & OBD_MD_FLFLAGS &&
+ oinfo.oi_oa->o_flags & OBD_FL_FLUSH))
+ rc = -EOPNOTSUPP;
+ else if (!(obdo->o_valid & OBD_MD_FLDATAVERSION))
+ rc = -EOPNOTSUPP;
+ else
+ *data_version = obdo->o_data_version;
+ }
+out_obdo:
+ OBD_FREE_PTR(obdo);
+out:
+ lov_lsm_put(obj, lsm);
+ RETURN(rc);
+}
+