* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 only,
* as published by the Free Software Foundation.
-
+ *
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License version 2 for more details. A copy is
* included in the COPYING file that accompanied this code.
-
+ *
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * version 2 along with this program; If not, see
+ * http://www.gnu.org/licenses/gpl-2.0.html
*
* GPL HEADER END
*/
* Copyright 2009 Sun Microsystems, Inc. All rights reserved
* Use is subject to license terms.
*
- * Copyright (c) 2012, 2013, Intel Corporation.
+ * Copyright (c) 2012, 2014, Intel Corporation.
*/
/*
* lustre/lod/lod_lov.c
*
- * Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
+ * A set of helpers to maintain Logical Object Volume (LOV)
+ * Extended Attribute (EA) and known OST targets
+ *
+ * Author: Alex Zhuravlev <alexey.zhuravlev@intel.com>
*/
#define DEBUG_SUBSYSTEM S_MDS
#include <obd_class.h>
#include <lustre_lfsck.h>
+#include <lustre_lmv.h>
#include "lod_internal.h"
-/*
- * Keep a refcount of lod->ltd_tgts usage to prevent racing with
- * addition/deletion. Any function that expects lov_tgts to remain stationary
- * must take a ref.
+/**
+ * Increase reference count on the target table.
+ *
+ * Increase reference count on the target table usage to prevent racing with
+ * addition/deletion. Any function that expects the table to remain
+ * stationary must take a ref.
*
- * \param lod - is the lod device from which we want to grab a reference
+ * \param[in] ltd target table (lod_ost_descs or lod_mdt_descs)
*/
void lod_getref(struct lod_tgt_descs *ltd)
{
mutex_unlock(<d->ltd_mutex);
}
-/*
- * Companion of lod_getref() to release a reference on the lod table.
- * If this is the last reference and the ost entry was scheduled for deletion,
- * the descriptor is removed from the array.
+/**
+ * Decrease reference count on the target table.
*
- * \param lod - is the lod device from which we release a reference
+ * Companion of lod_getref() to release a reference on the target table.
+ * If this is the last reference and the OST entry was scheduled for deletion,
+ * the descriptor is removed from the table.
+ *
+ * \param[in] lod LOD device from which we release a reference
+ * \param[in] ltd target table (lod_ost_descs or lod_mdt_descs)
*/
void lod_putref(struct lod_device *lod, struct lod_tgt_descs *ltd)
{
ltd->ltd_refcount--;
if (ltd->ltd_refcount == 0 && ltd->ltd_death_row) {
struct lod_tgt_desc *tgt_desc, *tmp;
- int idx;
- CFS_LIST_HEAD(kill);
+ struct list_head kill;
+ unsigned int idx;
CDEBUG(D_CONFIG, "destroying %d ltd desc\n",
ltd->ltd_death_row);
+ INIT_LIST_HEAD(&kill);
+
cfs_foreach_bit(ltd->ltd_tgt_bitmap, idx) {
tgt_desc = LTD_TGT(ltd, idx);
LASSERT(tgt_desc);
if (!tgt_desc->ltd_reap)
continue;
- cfs_list_add(&tgt_desc->ltd_kill, &kill);
+ list_add(&tgt_desc->ltd_kill, &kill);
LTD_TGT(ltd, idx) = NULL;
/*FIXME: only support ost pool for now */
if (ltd == &lod->lod_ost_descs) {
mutex_unlock(<d->ltd_mutex);
up_read(<d->ltd_rw_sem);
- cfs_list_for_each_entry_safe(tgt_desc, tmp, &kill, ltd_kill) {
+ list_for_each_entry_safe(tgt_desc, tmp, &kill, ltd_kill) {
int rc;
- cfs_list_del(&tgt_desc->ltd_kill);
+ list_del(&tgt_desc->ltd_kill);
if (ltd == &lod->lod_ost_descs) {
/* remove from QoS structures */
rc = qos_del_tgt(lod, tgt_desc);
}
}
+/**
+ * Expand size of target table.
+ *
+ * When the target table is full, we have to extend the table. To do so,
+ * we allocate new memory with some reserve, move data from the old table
+ * to the new one and release memory consumed by the old table.
+ * Notice we take ltd_rw_sem exclusively to ensure atomic switch.
+ *
+ * \param[in] ltd target table
+ * \param[in] newsize new size of the table
+ *
+ * \retval 0 on success
+ * \retval -ENOMEM if reallocation failed
+ */
static int ltd_bitmap_resize(struct lod_tgt_descs *ltd, __u32 newsize)
{
cfs_bitmap_t *new_bitmap, *old_bitmap = NULL;
return rc;
}
-/*
- * Connect LOD to a new OSP and add it to the device table.
+/**
+ * Connect LOD to a new OSP and add it to the target table.
*
- * \param env - is the environment passed by the caller
- * \param lod - is the LOD device to be connected to the new OSP
- * \param osp - is the name of OSP device name about to be added
- * \param index - is the OSP index
- * \param gen - is the generation number
- * \param tgt_index - is the group of the OSP.
- * \param type - is the type of device (mdc or osc)
+ * Connect to the OSP device passed, initialize all the internal
+ * structures related to the device and add it to the target table.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in] lod LOD device to be connected to the new OSP
+ * \param[in] osp name of OSP device name to be added
+ * \param[in] index index of the new target
+ * \param[in] gen target's generation number
+ * \param[in] tgt_index OSP's group
+ * \param[in] type type of device (mdc or osc)
+ * \param[in] active state of OSP: 0 - inactive, 1 - active
+ *
+ * \retval 0 if added successfully
+ * \retval negative error number on failure
*/
int lod_add_device(const struct lu_env *env, struct lod_device *lod,
char *osp, unsigned index, unsigned gen, int tgt_index,
OBD_CONNECT_AT |
OBD_CONNECT_FULL20 |
OBD_CONNECT_LFSCK;
- /* XXX set MDS-MDS flags, remove this when running this
- * on client*/
- data->ocd_connect_flags |= OBD_CONNECT_MDS_MDS;
spin_lock(&imp->imp_lock);
imp->imp_server_timeout = 1;
spin_unlock(&imp->imp_lock);
return rc;
}
-/*
- * helper function to schedule OST removal from the device table
+/**
+ * Schedule target removal from the target table.
+ *
+ * Mark the device as dead. The device is not removed here because it may
+ * still be in use. The device will be removed in lod_putref() when the
+ * last reference is released.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in] lod LOD device the target table belongs to
+ * \param[in] ltd target table
+ * \param[in] idx index of the target
+ * \param[in] for_ost type of the target: 0 - MDT, 1 - OST
*/
static void __lod_del_device(const struct lu_env *env, struct lod_device *lod,
struct lod_tgt_descs *ltd, unsigned idx,
}
}
+/**
+ * Schedule removal of all the targets from the given target table.
+ *
+ * See more details in the description for __lod_del_device()
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in] lod LOD device the target table belongs to
+ * \param[in] ltd target table
+ * \param[in] for_ost type of the target: MDT or OST
+ *
+ * \retval 0 always
+ */
int lod_fini_tgt(const struct lu_env *env, struct lod_device *lod,
struct lod_tgt_descs *ltd, bool for_ost)
{
- int idx;
+ unsigned int idx;
if (ltd->ltd_tgts_size <= 0)
return 0;
return 0;
}
-/*
- * Add support for administratively disabled OST (through the MGS).
- * Schedule a target for deletion. Disconnection and real removal from the
- * table takes place in lod_putref() once the last table user release its
- * reference.
+/**
+ * Remove device by name.
+ *
+ * Remove a device identified by \a osp from the target table. Given
+ * the device can be in use, the real deletion happens in lod_putref().
*
- * \param env - is the environment passed by the caller
- * \param lod - is the lod device currently connected to the OSP about to be
- * removed
- * \param osp - is the name of OSP device about to be removed
- * \param idx - is the OSP index
- * \param gen - is the generation number, not used currently
+ * \param[in] env execution environment for this thread
+ * \param[in] lod LOD device to be connected to the new OSP
+ * \param[in] ltd target table
+ * \param[in] osp name of OSP device to be removed
+ * \param[in] idx index of the target
+ * \param[in] gen generation number, not used currently
+ * \param[in] for_ost type of the target: 0 - MDT, 1 - OST
+ *
+ * \retval 0 if the device was scheduled for removal
+ * \retval -EINVAL if no device was found
*/
int lod_del_device(const struct lu_env *env, struct lod_device *lod,
struct lod_tgt_descs *ltd, char *osp, unsigned idx,
return(rc);
}
-int lod_ea_store_resize(struct lod_thread_info *info, int size)
+/**
+ * Resize per-thread storage to hold specified size.
+ *
+ * A helper function to resize per-thread temporary storage. This storage
+ * is used to process LOV/LVM EAs and may be quite large. We do not want to
+ * allocate/release it every time, so instead we put it into the env and
+ * reallocate on demand. The memory is released when the correspondent thread
+ * is finished.
+ *
+ * \param[in] info LOD-specific storage in the environment
+ * \param[in] size new size to grow the buffer to
+
+ * \retval 0 on success, -ENOMEM if reallocation failed
+ */
+int lod_ea_store_resize(struct lod_thread_info *info, size_t size)
{
- int round = size_roundup_power2(size);
+ __u32 round = size_roundup_power2(size);
LASSERT(round <=
lov_mds_md_size(LOV_MAX_STRIPE_COUNT, LOV_MAGIC_V3));
RETURN(0);
}
-/*
- * generate and write LOV EA for given striped object
+/**
+ * Make LOV EA for striped object.
+ *
+ * Generate striping information and store it in the LOV EA of the given
+ * object. The caller must ensure nobody else is calling the function
+ * against the object concurrently. The transaction must be started.
+ * FLDB service must be running as well; it's used to map FID to the target,
+ * which is stored in LOV EA.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in] lo LOD object
+ * \param[in] th transaction handle
+ *
+ * \retval 0 if LOV EA is stored successfully
+ * \retval negative error number on failure
*/
int lod_generate_and_set_lovea(const struct lu_env *env,
struct lod_object *lo, struct thandle *th)
struct lov_mds_md_v1 *lmm;
struct lov_ost_data_v1 *objs;
__u32 magic;
- int i, rc, lmm_size;
- int cplen = 0;
+ int i, rc;
+ size_t lmm_size;
ENTRY;
LASSERT(lo);
objs = &lmm->lmm_objects[0];
} else {
struct lov_mds_md_v3 *v3 = (struct lov_mds_md_v3 *) lmm;
- cplen = strlcpy(v3->lmm_pool_name, lo->ldo_pool,
+ size_t cplen = strlcpy(v3->lmm_pool_name, lo->ldo_pool,
sizeof(v3->lmm_pool_name));
if (cplen >= sizeof(v3->lmm_pool_name))
RETURN(-E2BIG);
RETURN(rc);
}
+/**
+ * Get LOV EA.
+ *
+ * Fill lti_ea_store buffer in the environment with a value for the given
+ * EA. The buffer is reallocated if the value doesn't fit.
+ *
+ * \param[in,out] env execution environment for this thread
+ * .lti_ea_store buffer is filled with EA's value
+ * \param[in] lo LOD object
+ * \param[in] name name of the EA
+ *
+ * \retval 0 if EA is fetched successfully
+ * \retval negative error number on failure
+ */
int lod_get_ea(const struct lu_env *env, struct lod_object *lo,
const char *name)
{
RETURN(rc);
}
-int lod_store_def_striping(const struct lu_env *env, struct dt_object *dt,
- struct thandle *th)
-{
- struct lod_thread_info *info = lod_env_info(env);
- struct lod_object *lo = lod_dt_obj(dt);
- struct dt_object *next = dt_object_child(dt);
- struct lov_user_md_v3 *v3;
- int rc;
- ENTRY;
-
- if (S_ISDIR(dt->do_lu.lo_header->loh_attr))
- RETURN(-ENOTDIR);
- /*
- * store striping defaults into new directory
- * used to implement defaults inheritance
- */
-
- /* probably nothing to inherite */
- if (lo->ldo_striping_cached == 0)
- RETURN(0);
-
- if (LOVEA_DELETE_VALUES(lo->ldo_def_stripe_size, lo->ldo_def_stripenr,
- lo->ldo_def_stripe_offset))
- RETURN(0);
-
- v3 = info->lti_ea_store;
- if (info->lti_ea_store_size < sizeof(*v3)) {
- rc = lod_ea_store_resize(info, sizeof(*v3));
- if (rc != 0)
- RETURN(rc);
- v3 = info->lti_ea_store;
- }
- memset(v3, 0, sizeof(*v3));
- v3->lmm_magic = cpu_to_le32(LOV_USER_MAGIC_V3);
- v3->lmm_stripe_count = cpu_to_le16(lo->ldo_def_stripenr);
- v3->lmm_stripe_offset = cpu_to_le16(lo->ldo_def_stripe_offset);
- v3->lmm_stripe_size = cpu_to_le32(lo->ldo_def_stripe_size);
- if (lo->ldo_pool != NULL)
- strlcpy(v3->lmm_pool_name, lo->ldo_pool,
- sizeof(v3->lmm_pool_name));
- info->lti_buf.lb_buf = v3;
- info->lti_buf.lb_len = sizeof(*v3);
- rc = dt_xattr_set(env, next, &info->lti_buf, XATTR_NAME_LOV, 0, th,
- BYPASS_CAPA);
-
- RETURN(rc);
-}
-
-static int validate_lod_and_idx(struct lod_device *md, int idx)
+/**
+ * Verify the target index is present in the current configuration.
+ *
+ * \param[in] md LOD device where the target table is stored
+ * \param[in] idx target's index
+ *
+ * \retval 0 if the index is present
+ * \retval -EINVAL if not
+ */
+static int validate_lod_and_idx(struct lod_device *md, __u32 idx)
{
if (unlikely(idx >= md->lod_ost_descs.ltd_tgts_size ||
!cfs_bitmap_check(md->lod_ost_bitmap, idx))) {
return 0;
}
-/*
- * allocate array of objects pointers, find/create objects
- * stripenr and other fields should be initialized by this moment
+/**
+ * Instantiate objects for stripes.
+ *
+ * Allocate and initialize LU-objects representing the stripes. The number
+ * of the stripes (ldo_stripenr) must be initialized already. The caller
+ * must ensure nobody else is calling the function on the object at the same
+ * time. FLDB service must be running to be able to map a FID to the targets
+ * and find appropriate device representing that target.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in,out] lo LOD object
+ * \param[in] objs an array of IDs to creates the objects from
+ *
+ * \retval 0 if the objects are instantiated successfully
+ * \retval negative error number on failure
*/
int lod_initialize_objects(const struct lu_env *env, struct lod_object *lo,
struct lov_ost_data_v1 *objs)
struct lu_device *nd;
struct dt_object **stripe;
int stripe_len;
- int i, idx, rc = 0;
+ int i, rc = 0;
+ __u32 idx;
ENTRY;
LASSERT(lo != NULL);
RETURN(rc);
}
-/*
- * Parse striping information stored in lti_ea_store
+/**
+ * Instantiate objects for striping.
+ *
+ * Parse striping information in \a buf and instantiate the objects
+ * representing the stripes.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in] lo LOD object
+ * \param[in] buf buffer storing LOV EA to parse
+ *
+ * \retval 0 if parsing and objects creation succeed
+ * \retval negative error number on failure
*/
int lod_parse_striping(const struct lu_env *env, struct lod_object *lo,
const struct lu_buf *buf)
RETURN(rc);
}
+/**
+ * Initialize the object representing the stripes.
+ *
+ * Unless the stripes are initialized already, fetch LOV (for regular
+ * objects) or LMV (for directory objects) EA and call lod_parse_striping()
+ * to instantiate the objects representing the stripes.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in,out] lo LOD object
+ *
+ * \retval 0 if parsing and object creation succeed
+ * \retval negative error number on failure
+ */
int lod_load_striping_locked(const struct lu_env *env, struct lod_object *lo)
{
struct lod_thread_info *info = lod_env_info(env);
+ struct lu_buf *buf = &info->lti_buf;
struct dt_object *next = dt_object_child(&lo->ldo_obj);
int rc = 0;
ENTRY;
* there is LOV EA (striping information) in this object
* let's parse it and create in-core objects for the stripes
*/
- info->lti_buf.lb_buf = info->lti_ea_store;
- info->lti_buf.lb_len = info->lti_ea_store_size;
- rc = lod_parse_striping(env, lo, &info->lti_buf);
+ buf->lb_buf = info->lti_ea_store;
+ buf->lb_len = info->lti_ea_store_size;
+ rc = lod_parse_striping(env, lo, buf);
} else if (S_ISDIR(lu_object_attr(lod2lu_obj(lo)))) {
rc = lod_get_lmv_ea(env, lo);
- if (rc <= 0)
- GOTO(out, rc);
+ if (rc < (typeof(rc))sizeof(struct lmv_mds_md_v1))
+ GOTO(out, rc = rc > 0 ? -EINVAL : rc);
+
+ buf->lb_buf = info->lti_ea_store;
+ buf->lb_len = info->lti_ea_store_size;
+ if (rc == sizeof(struct lmv_mds_md_v1)) {
+ rc = lod_load_lmv_shards(env, lo, buf, true);
+ if (buf->lb_buf != info->lti_ea_store) {
+ OBD_FREE_LARGE(info->lti_ea_store,
+ info->lti_ea_store_size);
+ info->lti_ea_store = buf->lb_buf;
+ info->lti_ea_store_size = buf->lb_len;
+ }
+
+ if (rc < 0)
+ GOTO(out, rc);
+ }
+
/*
* there is LOV EA (striping information) in this object
* let's parse it and create in-core objects for the stripes
*/
- info->lti_buf.lb_buf = info->lti_ea_store;
- info->lti_buf.lb_len = info->lti_ea_store_size;
- rc = lod_parse_dir_striping(env, lo, &info->lti_buf);
+ rc = lod_parse_dir_striping(env, lo, buf);
}
out:
RETURN(rc);
}
/**
- * Load and parse striping information, create in-core representation for the
- * stripes
+ * A generic function to initialize the stripe objects.
+ *
+ * A protected version of lod_load_striping_locked() - load the striping
+ * information from storage, parse that and instantiate LU objects to
+ * represent the stripes. The LOD object \a lo supplies a pointer to the
+ * next sub-object in the LU stack so we can lock it. Also use \a lo to
+ * return an array of references to the newly instantiated objects.
+ *
+ * \param[in] env execution environment for this thread
+ * \param[in,out] lo LOD object, where striping is stored and
+ * which gets an array of references
+ *
+ * \retval 0 if parsing and object creation succeed
+ * \retval negative error number on failure
**/
int lod_load_striping(const struct lu_env *env, struct lod_object *lo)
{
return rc;
}
-/* verify the striping information for directory */
+/**
+ * Verify striping.
+ *
+ * Check the validity of all fields including the magic, stripe size,
+ * stripe count, stripe offset and that the pool is present. Also check
+ * that each target index points to an existing target. The additional
+ * \a is_from_disk turns additional checks. In some cases zero fields
+ * are allowed (like pattern=0).
+ *
+ * \param[in] d LOD device
+ * \param[in] buf buffer with LOV EA to verify
+ * \param[in] is_from_disk 0 - from user, allow some fields to be 0
+ * 1 - from disk, do not allow
+ *
+ * \retval 0 if the striping is valid
+ * \retval -EINVAL if striping is invalid
+ */
int lod_verify_striping(struct lod_device *d, const struct lu_buf *buf,
bool is_from_disk)
{
LASSERT(sizeof(*lum) < sizeof(*lum3));
if (buf->lb_len < sizeof(*lum)) {
- CDEBUG(D_IOCTL, "buf len %zd too small for lov_user_md\n",
+ CDEBUG(D_IOCTL, "buf len %zu too small for lov_user_md\n",
buf->lb_len);
GOTO(out, rc = -EINVAL);
}
GOTO(out, rc = -EINVAL);
}
- /* an offset of -1 is treated as a "special" valid offset */
stripe_offset = le16_to_cpu(lum->lmm_stripe_offset);
- if (stripe_offset != (typeof(stripe_offset))-1) {
+ if (stripe_offset != LOV_OFFSET_DEFAULT) {
/* if offset is not within valid range [0, osts_size) */
if (stripe_offset >= d->lod_osts_size) {
CDEBUG(D_IOCTL, "stripe offset %u >= bitmap size %u\n",
stripe_count = le16_to_cpu(lum->lmm_stripe_count);
if (buf->lb_len != lum_size) {
- CDEBUG(D_IOCTL, "invalid buf len %zd for lov_user_md with "
+ CDEBUG(D_IOCTL, "invalid buf len %zu for lov_user_md with "
"magic %#x and stripe_count %u\n",
buf->lb_len, magic, stripe_count);
GOTO(out, rc = -EINVAL);
lum3 = buf->lb_buf;
if (buf->lb_len < sizeof(*lum3)) {
- CDEBUG(D_IOCTL, "buf len %zd too small for lov_user_md_v3\n",
+ CDEBUG(D_IOCTL, "buf len %zu too small for lov_user_md_v3\n",
buf->lb_len);
GOTO(out, rc = -EINVAL);
}
if (pool == NULL)
goto out;
- if (stripe_offset != (typeof(stripe_offset))-1) {
+ if (stripe_offset != LOV_OFFSET_DEFAULT) {
rc = lod_check_index_in_pool(stripe_offset, pool);
if (rc < 0)
GOTO(out, rc = -EINVAL);
*val = LOV_DESC_QOS_MAXAGE_DEFAULT;
}
+/**
+ * Used to fix insane default striping.
+ *
+ * \param[in] desc striping description
+ */
void lod_fix_desc(struct lov_desc *desc)
{
lod_fix_desc_stripe_size(&desc->ld_default_stripe_size);
lod_fix_desc_qos_maxage(&desc->ld_qos_maxage);
}
+/**
+ * Initialize the structures used to store pools and default striping.
+ *
+ * \param[in] lod LOD device
+ * \param[in] lcfg configuration structure storing default striping.
+ *
+ * \retval 0 if initialization succeeds
+ * \retval negative error number on failure
+ */
int lod_pools_init(struct lod_device *lod, struct lustre_cfg *lcfg)
{
struct obd_device *obd;
lod->lod_sp_me = LUSTRE_SP_CLI;
/* Set up allocation policy (QoS and RR) */
- CFS_INIT_LIST_HEAD(&lod->lod_qos.lq_oss_list);
+ INIT_LIST_HEAD(&lod->lod_qos.lq_oss_list);
init_rwsem(&lod->lod_qos.lq_rw_sem);
lod->lod_qos.lq_dirty = 1;
lod->lod_qos.lq_rr.lqr_dirty = 1;
if (lod->lod_pools_hash_body == NULL)
RETURN(-ENOMEM);
- CFS_INIT_LIST_HEAD(&lod->lod_pool_list);
+ INIT_LIST_HEAD(&lod->lod_pool_list);
lod->lod_pool_count = 0;
rc = lod_ost_pool_init(&lod->lod_pool_info, 0);
if (rc)
return rc;
}
+/**
+ * Release the structures describing the pools.
+ *
+ * \param[in] lod LOD device from which we release the structures
+ *
+ * \retval 0 always
+ */
int lod_pools_fini(struct lod_device *lod)
{
struct obd_device *obd = lod2obd(lod);
- cfs_list_t *pos, *tmp;
- struct pool_desc *pool;
+ struct pool_desc *pool, *tmp;
ENTRY;
- cfs_list_for_each_safe(pos, tmp, &lod->lod_pool_list) {
- pool = cfs_list_entry(pos, struct pool_desc, pool_list);
+ list_for_each_entry_safe(pool, tmp, &lod->lod_pool_list, pool_list) {
/* free pool structs */
CDEBUG(D_INFO, "delete pool %p\n", pool);
/* In the function below, .hs_keycmp resolves to
RETURN(0);
}
-
git://git.whamcloud.com / fs / lustre-release.git / blobdiff