blob: 0cb1abd535e38469201478ee597e74045e593bc5 [file] [log] [blame]
/*
* Module for pnfs flexfile layout driver.
*
* Copyright (c) 2014, Primary Data, Inc. All rights reserved.
*
* Tao Peng <bergwolf@primarydata.com>
*/
#include <linux/nfs_fs.h>
#include <linux/nfs_page.h>
#include <linux/module.h>
#include <linux/sunrpc/metrics.h>
#include "flexfilelayout.h"
#include "../nfs4session.h"
#include "../nfs4idmap.h"
#include "../internal.h"
#include "../delegation.h"
#include "../nfs4trace.h"
#include "../iostat.h"
#include "../nfs.h"
#include "../nfs42.h"
#define NFSDBG_FACILITY NFSDBG_PNFS_LD
#define FF_LAYOUT_POLL_RETRY_MAX (15*HZ)
static struct pnfs_layout_hdr *
ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
{
struct nfs4_flexfile_layout *ffl;
ffl = kzalloc(sizeof(*ffl), gfp_flags);
if (ffl) {
INIT_LIST_HEAD(&ffl->error_list);
INIT_LIST_HEAD(&ffl->mirrors);
return &ffl->generic_hdr;
} else
return NULL;
}
static void
ff_layout_free_layout_hdr(struct pnfs_layout_hdr *lo)
{
struct nfs4_ff_layout_ds_err *err, *n;
list_for_each_entry_safe(err, n, &FF_LAYOUT_FROM_HDR(lo)->error_list,
list) {
list_del(&err->list);
kfree(err);
}
kfree(FF_LAYOUT_FROM_HDR(lo));
}
static int decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
{
__be32 *p;
p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
if (unlikely(p == NULL))
return -ENOBUFS;
memcpy(stateid, p, NFS4_STATEID_SIZE);
dprintk("%s: stateid id= [%x%x%x%x]\n", __func__,
p[0], p[1], p[2], p[3]);
return 0;
}
static int decode_deviceid(struct xdr_stream *xdr, struct nfs4_deviceid *devid)
{
__be32 *p;
p = xdr_inline_decode(xdr, NFS4_DEVICEID4_SIZE);
if (unlikely(!p))
return -ENOBUFS;
memcpy(devid, p, NFS4_DEVICEID4_SIZE);
nfs4_print_deviceid(devid);
return 0;
}
static int decode_nfs_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
{
__be32 *p;
p = xdr_inline_decode(xdr, 4);
if (unlikely(!p))
return -ENOBUFS;
fh->size = be32_to_cpup(p++);
if (fh->size > sizeof(struct nfs_fh)) {
printk(KERN_ERR "NFS flexfiles: Too big fh received %d\n",
fh->size);
return -EOVERFLOW;
}
/* fh.data */
p = xdr_inline_decode(xdr, fh->size);
if (unlikely(!p))
return -ENOBUFS;
memcpy(&fh->data, p, fh->size);
dprintk("%s: fh len %d\n", __func__, fh->size);
return 0;
}
/*
* Currently only stringified uids and gids are accepted.
* I.e., kerberos is not supported to the DSes, so no pricipals.
*
* That means that one common function will suffice, but when
* principals are added, this should be split to accomodate
* calls to both nfs_map_name_to_uid() and nfs_map_group_to_gid().
*/
static int
decode_name(struct xdr_stream *xdr, u32 *id)
{
__be32 *p;
int len;
/* opaque_length(4)*/
p = xdr_inline_decode(xdr, 4);
if (unlikely(!p))
return -ENOBUFS;
len = be32_to_cpup(p++);
if (len < 0)
return -EINVAL;
dprintk("%s: len %u\n", __func__, len);
/* opaque body */
p = xdr_inline_decode(xdr, len);
if (unlikely(!p))
return -ENOBUFS;
if (!nfs_map_string_to_numeric((char *)p, len, id))
return -EINVAL;
return 0;
}
static bool ff_mirror_match_fh(const struct nfs4_ff_layout_mirror *m1,
const struct nfs4_ff_layout_mirror *m2)
{
int i, j;
if (m1->fh_versions_cnt != m2->fh_versions_cnt)
return false;
for (i = 0; i < m1->fh_versions_cnt; i++) {
bool found_fh = false;
for (j = 0; j < m2->fh_versions_cnt; j++) {
if (nfs_compare_fh(&m1->fh_versions[i],
&m2->fh_versions[j]) == 0) {
found_fh = true;
break;
}
}
if (!found_fh)
return false;
}
return true;
}
static struct nfs4_ff_layout_mirror *
ff_layout_add_mirror(struct pnfs_layout_hdr *lo,
struct nfs4_ff_layout_mirror *mirror)
{
struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
struct nfs4_ff_layout_mirror *pos;
struct inode *inode = lo->plh_inode;
spin_lock(&inode->i_lock);
list_for_each_entry(pos, &ff_layout->mirrors, mirrors) {
if (mirror->mirror_ds != pos->mirror_ds)
continue;
if (!ff_mirror_match_fh(mirror, pos))
continue;
if (atomic_inc_not_zero(&pos->ref)) {
spin_unlock(&inode->i_lock);
return pos;
}
}
list_add(&mirror->mirrors, &ff_layout->mirrors);
mirror->layout = lo;
spin_unlock(&inode->i_lock);
return mirror;
}
static void
ff_layout_remove_mirror(struct nfs4_ff_layout_mirror *mirror)
{
struct inode *inode;
if (mirror->layout == NULL)
return;
inode = mirror->layout->plh_inode;
spin_lock(&inode->i_lock);
list_del(&mirror->mirrors);
spin_unlock(&inode->i_lock);
mirror->layout = NULL;
}
static struct nfs4_ff_layout_mirror *ff_layout_alloc_mirror(gfp_t gfp_flags)
{
struct nfs4_ff_layout_mirror *mirror;
mirror = kzalloc(sizeof(*mirror), gfp_flags);
if (mirror != NULL) {
spin_lock_init(&mirror->lock);
atomic_set(&mirror->ref, 1);
INIT_LIST_HEAD(&mirror->mirrors);
}
return mirror;
}
static void ff_layout_free_mirror(struct nfs4_ff_layout_mirror *mirror)
{
ff_layout_remove_mirror(mirror);
kfree(mirror->fh_versions);
if (mirror->cred)
put_rpccred(mirror->cred);
nfs4_ff_layout_put_deviceid(mirror->mirror_ds);
kfree(mirror);
}
static void ff_layout_put_mirror(struct nfs4_ff_layout_mirror *mirror)
{
if (mirror != NULL && atomic_dec_and_test(&mirror->ref))
ff_layout_free_mirror(mirror);
}
static void ff_layout_free_mirror_array(struct nfs4_ff_layout_segment *fls)
{
int i;
if (fls->mirror_array) {
for (i = 0; i < fls->mirror_array_cnt; i++) {
/* normally mirror_ds is freed in
* .free_deviceid_node but we still do it here
* for .alloc_lseg error path */
ff_layout_put_mirror(fls->mirror_array[i]);
}
kfree(fls->mirror_array);
fls->mirror_array = NULL;
}
}
static int ff_layout_check_layout(struct nfs4_layoutget_res *lgr)
{
int ret = 0;
dprintk("--> %s\n", __func__);
/* FIXME: remove this check when layout segment support is added */
if (lgr->range.offset != 0 ||
lgr->range.length != NFS4_MAX_UINT64) {
dprintk("%s Only whole file layouts supported. Use MDS i/o\n",
__func__);
ret = -EINVAL;
}
dprintk("--> %s returns %d\n", __func__, ret);
return ret;
}
static void _ff_layout_free_lseg(struct nfs4_ff_layout_segment *fls)
{
if (fls) {
ff_layout_free_mirror_array(fls);
kfree(fls);
}
}
static bool
ff_lseg_range_is_after(const struct pnfs_layout_range *l1,
const struct pnfs_layout_range *l2)
{
u64 end1, end2;
if (l1->iomode != l2->iomode)
return l1->iomode != IOMODE_READ;
end1 = pnfs_calc_offset_end(l1->offset, l1->length);
end2 = pnfs_calc_offset_end(l2->offset, l2->length);
if (end1 < l2->offset)
return false;
if (end2 < l1->offset)
return true;
return l2->offset <= l1->offset;
}
static bool
ff_lseg_merge(struct pnfs_layout_segment *new,
struct pnfs_layout_segment *old)
{
u64 new_end, old_end;
if (new->pls_range.iomode != old->pls_range.iomode)
return false;
old_end = pnfs_calc_offset_end(old->pls_range.offset,
old->pls_range.length);
if (old_end < new->pls_range.offset)
return false;
new_end = pnfs_calc_offset_end(new->pls_range.offset,
new->pls_range.length);
if (new_end < old->pls_range.offset)
return false;
/* Mergeable: copy info from 'old' to 'new' */
if (new_end < old_end)
new_end = old_end;
if (new->pls_range.offset < old->pls_range.offset)
new->pls_range.offset = old->pls_range.offset;
new->pls_range.length = pnfs_calc_offset_length(new->pls_range.offset,
new_end);
if (test_bit(NFS_LSEG_ROC, &old->pls_flags))
set_bit(NFS_LSEG_ROC, &new->pls_flags);
if (test_bit(NFS_LSEG_LAYOUTRETURN, &old->pls_flags))
set_bit(NFS_LSEG_LAYOUTRETURN, &new->pls_flags);
return true;
}
static void
ff_layout_add_lseg(struct pnfs_layout_hdr *lo,
struct pnfs_layout_segment *lseg,
struct list_head *free_me)
{
pnfs_generic_layout_insert_lseg(lo, lseg,
ff_lseg_range_is_after,
ff_lseg_merge,
free_me);
}
static void ff_layout_sort_mirrors(struct nfs4_ff_layout_segment *fls)
{
int i, j;
for (i = 0; i < fls->mirror_array_cnt - 1; i++) {
for (j = i + 1; j < fls->mirror_array_cnt; j++)
if (fls->mirror_array[i]->efficiency <
fls->mirror_array[j]->efficiency)
swap(fls->mirror_array[i],
fls->mirror_array[j]);
}
}
static void ff_layout_mark_devices_valid(struct nfs4_ff_layout_segment *fls)
{
struct nfs4_deviceid_node *node;
int i;
if (!(fls->flags & FF_FLAGS_NO_IO_THRU_MDS))
return;
for (i = 0; i < fls->mirror_array_cnt; i++) {
node = &fls->mirror_array[i]->mirror_ds->id_node;
clear_bit(NFS_DEVICEID_UNAVAILABLE, &node->flags);
}
}
static struct pnfs_layout_segment *
ff_layout_alloc_lseg(struct pnfs_layout_hdr *lh,
struct nfs4_layoutget_res *lgr,
gfp_t gfp_flags)
{
struct pnfs_layout_segment *ret;
struct nfs4_ff_layout_segment *fls = NULL;
struct xdr_stream stream;
struct xdr_buf buf;
struct page *scratch;
u64 stripe_unit;
u32 mirror_array_cnt;
__be32 *p;
int i, rc;
dprintk("--> %s\n", __func__);
scratch = alloc_page(gfp_flags);
if (!scratch)
return ERR_PTR(-ENOMEM);
xdr_init_decode_pages(&stream, &buf, lgr->layoutp->pages,
lgr->layoutp->len);
xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
/* stripe unit and mirror_array_cnt */
rc = -EIO;
p = xdr_inline_decode(&stream, 8 + 4);
if (!p)
goto out_err_free;
p = xdr_decode_hyper(p, &stripe_unit);
mirror_array_cnt = be32_to_cpup(p++);
dprintk("%s: stripe_unit=%llu mirror_array_cnt=%u\n", __func__,
stripe_unit, mirror_array_cnt);
if (mirror_array_cnt > NFS4_FLEXFILE_LAYOUT_MAX_MIRROR_CNT ||
mirror_array_cnt == 0)
goto out_err_free;
rc = -ENOMEM;
fls = kzalloc(sizeof(*fls), gfp_flags);
if (!fls)
goto out_err_free;
fls->mirror_array_cnt = mirror_array_cnt;
fls->stripe_unit = stripe_unit;
fls->mirror_array = kcalloc(fls->mirror_array_cnt,
sizeof(fls->mirror_array[0]), gfp_flags);
if (fls->mirror_array == NULL)
goto out_err_free;
for (i = 0; i < fls->mirror_array_cnt; i++) {
struct nfs4_ff_layout_mirror *mirror;
struct nfs4_deviceid devid;
struct nfs4_deviceid_node *idnode;
u32 ds_count;
u32 fh_count;
int j;
rc = -EIO;
p = xdr_inline_decode(&stream, 4);
if (!p)
goto out_err_free;
ds_count = be32_to_cpup(p);
/* FIXME: allow for striping? */
if (ds_count != 1)
goto out_err_free;
fls->mirror_array[i] = ff_layout_alloc_mirror(gfp_flags);
if (fls->mirror_array[i] == NULL) {
rc = -ENOMEM;
goto out_err_free;
}
fls->mirror_array[i]->ds_count = ds_count;
/* deviceid */
rc = decode_deviceid(&stream, &devid);
if (rc)
goto out_err_free;
idnode = nfs4_find_get_deviceid(NFS_SERVER(lh->plh_inode),
&devid, lh->plh_lc_cred,
gfp_flags);
/*
* upon success, mirror_ds is allocated by previous
* getdeviceinfo, or newly by .alloc_deviceid_node
* nfs4_find_get_deviceid failure is indeed getdeviceinfo falure
*/
if (idnode)
fls->mirror_array[i]->mirror_ds =
FF_LAYOUT_MIRROR_DS(idnode);
else
goto out_err_free;
/* efficiency */
rc = -EIO;
p = xdr_inline_decode(&stream, 4);
if (!p)
goto out_err_free;
fls->mirror_array[i]->efficiency = be32_to_cpup(p);
/* stateid */
rc = decode_stateid(&stream, &fls->mirror_array[i]->stateid);
if (rc)
goto out_err_free;
/* fh */
p = xdr_inline_decode(&stream, 4);
if (!p)
goto out_err_free;
fh_count = be32_to_cpup(p);
fls->mirror_array[i]->fh_versions =
kzalloc(fh_count * sizeof(struct nfs_fh),
gfp_flags);
if (fls->mirror_array[i]->fh_versions == NULL) {
rc = -ENOMEM;
goto out_err_free;
}
for (j = 0; j < fh_count; j++) {
rc = decode_nfs_fh(&stream,
&fls->mirror_array[i]->fh_versions[j]);
if (rc)
goto out_err_free;
}
fls->mirror_array[i]->fh_versions_cnt = fh_count;
/* user */
rc = decode_name(&stream, &fls->mirror_array[i]->uid);
if (rc)
goto out_err_free;
/* group */
rc = decode_name(&stream, &fls->mirror_array[i]->gid);
if (rc)
goto out_err_free;
mirror = ff_layout_add_mirror(lh, fls->mirror_array[i]);
if (mirror != fls->mirror_array[i]) {
ff_layout_free_mirror(fls->mirror_array[i]);
fls->mirror_array[i] = mirror;
}
dprintk("%s: uid %d gid %d\n", __func__,
fls->mirror_array[i]->uid,
fls->mirror_array[i]->gid);
}
p = xdr_inline_decode(&stream, 4);
if (!p)
goto out_sort_mirrors;
fls->flags = be32_to_cpup(p);
p = xdr_inline_decode(&stream, 4);
if (!p)
goto out_sort_mirrors;
for (i=0; i < fls->mirror_array_cnt; i++)
fls->mirror_array[i]->report_interval = be32_to_cpup(p);
out_sort_mirrors:
ff_layout_sort_mirrors(fls);
rc = ff_layout_check_layout(lgr);
if (rc)
goto out_err_free;
ff_layout_mark_devices_valid(fls);
ret = &fls->generic_hdr;
dprintk("<-- %s (success)\n", __func__);
out_free_page:
__free_page(scratch);
return ret;
out_err_free:
_ff_layout_free_lseg(fls);
ret = ERR_PTR(rc);
dprintk("<-- %s (%d)\n", __func__, rc);
goto out_free_page;
}
static bool ff_layout_has_rw_segments(struct pnfs_layout_hdr *layout)
{
struct pnfs_layout_segment *lseg;
list_for_each_entry(lseg, &layout->plh_segs, pls_list)
if (lseg->pls_range.iomode == IOMODE_RW)
return true;
return false;
}
static void
ff_layout_free_lseg(struct pnfs_layout_segment *lseg)
{
struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
dprintk("--> %s\n", __func__);
if (lseg->pls_range.iomode == IOMODE_RW) {
struct nfs4_flexfile_layout *ffl;
struct inode *inode;
ffl = FF_LAYOUT_FROM_HDR(lseg->pls_layout);
inode = ffl->generic_hdr.plh_inode;
spin_lock(&inode->i_lock);
if (!ff_layout_has_rw_segments(lseg->pls_layout)) {
ffl->commit_info.nbuckets = 0;
kfree(ffl->commit_info.buckets);
ffl->commit_info.buckets = NULL;
}
spin_unlock(&inode->i_lock);
}
_ff_layout_free_lseg(fls);
}
/* Return 1 until we have multiple lsegs support */
static int
ff_layout_get_lseg_count(struct nfs4_ff_layout_segment *fls)
{
return 1;
}
static void
nfs4_ff_start_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
{
/* first IO request? */
if (atomic_inc_return(&timer->n_ops) == 1) {
timer->start_time = now;
}
}
static ktime_t
nfs4_ff_end_busy_timer(struct nfs4_ff_busy_timer *timer, ktime_t now)
{
ktime_t start;
if (atomic_dec_return(&timer->n_ops) < 0)
WARN_ON_ONCE(1);
start = timer->start_time;
timer->start_time = now;
return ktime_sub(now, start);
}
static bool
nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
struct nfs4_ff_layoutstat *layoutstat,
ktime_t now)
{
static const ktime_t notime = {0};
s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
if (ktime_equal(mirror->start_time, notime))
mirror->start_time = now;
if (ktime_equal(mirror->last_report_time, notime))
mirror->last_report_time = now;
if (mirror->report_interval != 0)
report_interval = (s64)mirror->report_interval * 1000LL;
else if (layoutstats_timer != 0)
report_interval = (s64)layoutstats_timer * 1000LL;
if (ktime_to_ms(ktime_sub(now, mirror->last_report_time)) >=
report_interval) {
mirror->last_report_time = now;
return true;
}
return false;
}
static void
nfs4_ff_layout_stat_io_update_requested(struct nfs4_ff_layoutstat *layoutstat,
__u64 requested)
{
struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
iostat->ops_requested++;
iostat->bytes_requested += requested;
}
static void
nfs4_ff_layout_stat_io_update_completed(struct nfs4_ff_layoutstat *layoutstat,
__u64 requested,
__u64 completed,
ktime_t time_completed,
ktime_t time_started)
{
struct nfs4_ff_io_stat *iostat = &layoutstat->io_stat;
ktime_t completion_time = ktime_sub(time_completed, time_started);
ktime_t timer;
iostat->ops_completed++;
iostat->bytes_completed += completed;
iostat->bytes_not_delivered += requested - completed;
timer = nfs4_ff_end_busy_timer(&layoutstat->busy_timer, time_completed);
iostat->total_busy_time =
ktime_add(iostat->total_busy_time, timer);
iostat->aggregate_completion_time =
ktime_add(iostat->aggregate_completion_time,
completion_time);
}
static void
nfs4_ff_layout_stat_io_start_read(struct inode *inode,
struct nfs4_ff_layout_mirror *mirror,
__u64 requested, ktime_t now)
{
bool report;
spin_lock(&mirror->lock);
report = nfs4_ff_layoutstat_start_io(mirror, &mirror->read_stat, now);
nfs4_ff_layout_stat_io_update_requested(&mirror->read_stat, requested);
spin_unlock(&mirror->lock);
if (report)
pnfs_report_layoutstat(inode, GFP_KERNEL);
}
static void
nfs4_ff_layout_stat_io_end_read(struct rpc_task *task,
struct nfs4_ff_layout_mirror *mirror,
__u64 requested,
__u64 completed)
{
spin_lock(&mirror->lock);
nfs4_ff_layout_stat_io_update_completed(&mirror->read_stat,
requested, completed,
ktime_get(), task->tk_start);
spin_unlock(&mirror->lock);
}
static void
nfs4_ff_layout_stat_io_start_write(struct inode *inode,
struct nfs4_ff_layout_mirror *mirror,
__u64 requested, ktime_t now)
{
bool report;
spin_lock(&mirror->lock);
report = nfs4_ff_layoutstat_start_io(mirror , &mirror->write_stat, now);
nfs4_ff_layout_stat_io_update_requested(&mirror->write_stat, requested);
spin_unlock(&mirror->lock);
if (report)
pnfs_report_layoutstat(inode, GFP_NOIO);
}
static void
nfs4_ff_layout_stat_io_end_write(struct rpc_task *task,
struct nfs4_ff_layout_mirror *mirror,
__u64 requested,
__u64 completed,
enum nfs3_stable_how committed)
{
if (committed == NFS_UNSTABLE)
requested = completed = 0;
spin_lock(&mirror->lock);
nfs4_ff_layout_stat_io_update_completed(&mirror->write_stat,
requested, completed, ktime_get(), task->tk_start);
spin_unlock(&mirror->lock);
}
static int
ff_layout_alloc_commit_info(struct pnfs_layout_segment *lseg,
struct nfs_commit_info *cinfo,
gfp_t gfp_flags)
{
struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
struct pnfs_commit_bucket *buckets;
int size;
if (cinfo->ds->nbuckets != 0) {
/* This assumes there is only one RW lseg per file.
* To support multiple lseg per file, we need to
* change struct pnfs_commit_bucket to allow dynamic
* increasing nbuckets.
*/
return 0;
}
size = ff_layout_get_lseg_count(fls) * FF_LAYOUT_MIRROR_COUNT(lseg);
buckets = kcalloc(size, sizeof(struct pnfs_commit_bucket),
gfp_flags);
if (!buckets)
return -ENOMEM;
else {
int i;
spin_lock(cinfo->lock);
if (cinfo->ds->nbuckets != 0)
kfree(buckets);
else {
cinfo->ds->buckets = buckets;
cinfo->ds->nbuckets = size;
for (i = 0; i < size; i++) {
INIT_LIST_HEAD(&buckets[i].written);
INIT_LIST_HEAD(&buckets[i].committing);
/* mark direct verifier as unset */
buckets[i].direct_verf.committed =
NFS_INVALID_STABLE_HOW;
}
}
spin_unlock(cinfo->lock);
return 0;
}
}
static struct nfs4_pnfs_ds *
ff_layout_choose_best_ds_for_read(struct pnfs_layout_segment *lseg,
int start_idx,
int *best_idx)
{
struct nfs4_ff_layout_segment *fls = FF_LAYOUT_LSEG(lseg);
struct nfs4_pnfs_ds *ds;
int idx;
/* mirrors are sorted by efficiency */
for (idx = start_idx; idx < fls->mirror_array_cnt; idx++) {
ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
if (ds) {
*best_idx = idx;
return ds;
}
}
return NULL;
}
static void
ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
struct nfs_page *req)
{
struct nfs_pgio_mirror *pgm;
struct nfs4_ff_layout_mirror *mirror;
struct nfs4_pnfs_ds *ds;
int ds_idx;
/* Use full layout for now */
if (!pgio->pg_lseg) {
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
0,
NFS4_MAX_UINT64,
IOMODE_READ,
GFP_KERNEL);
if (IS_ERR(pgio->pg_lseg)) {
pgio->pg_error = PTR_ERR(pgio->pg_lseg);
pgio->pg_lseg = NULL;
return;
}
}
/* If no lseg, fall back to read through mds */
if (pgio->pg_lseg == NULL)
goto out_mds;
ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
if (!ds)
goto out_mds;
mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
pgio->pg_mirror_idx = ds_idx;
/* read always uses only one mirror - idx 0 for pgio layer */
pgm = &pgio->pg_mirrors[0];
pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].rsize;
return;
out_mds:
pnfs_put_lseg(pgio->pg_lseg);
pgio->pg_lseg = NULL;
nfs_pageio_reset_read_mds(pgio);
}
static void
ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
struct nfs_page *req)
{
struct nfs4_ff_layout_mirror *mirror;
struct nfs_pgio_mirror *pgm;
struct nfs_commit_info cinfo;
struct nfs4_pnfs_ds *ds;
int i;
int status;
if (!pgio->pg_lseg) {
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
0,
NFS4_MAX_UINT64,
IOMODE_RW,
GFP_NOFS);
if (IS_ERR(pgio->pg_lseg)) {
pgio->pg_error = PTR_ERR(pgio->pg_lseg);
pgio->pg_lseg = NULL;
return;
}
}
/* If no lseg, fall back to write through mds */
if (pgio->pg_lseg == NULL)
goto out_mds;
nfs_init_cinfo(&cinfo, pgio->pg_inode, pgio->pg_dreq);
status = ff_layout_alloc_commit_info(pgio->pg_lseg, &cinfo, GFP_NOFS);
if (status < 0)
goto out_mds;
/* Use a direct mapping of ds_idx to pgio mirror_idx */
if (WARN_ON_ONCE(pgio->pg_mirror_count !=
FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)))
goto out_mds;
for (i = 0; i < pgio->pg_mirror_count; i++) {
ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
if (!ds)
goto out_mds;
pgm = &pgio->pg_mirrors[i];
mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
}
return;
out_mds:
pnfs_put_lseg(pgio->pg_lseg);
pgio->pg_lseg = NULL;
nfs_pageio_reset_write_mds(pgio);
}
static unsigned int
ff_layout_pg_get_mirror_count_write(struct nfs_pageio_descriptor *pgio,
struct nfs_page *req)
{
if (!pgio->pg_lseg) {
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
0,
NFS4_MAX_UINT64,
IOMODE_RW,
GFP_NOFS);
if (IS_ERR(pgio->pg_lseg)) {
pgio->pg_error = PTR_ERR(pgio->pg_lseg);
pgio->pg_lseg = NULL;
goto out;
}
}
if (pgio->pg_lseg)
return FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg);
/* no lseg means that pnfs is not in use, so no mirroring here */
nfs_pageio_reset_write_mds(pgio);
out:
return 1;
}
static const struct nfs_pageio_ops ff_layout_pg_read_ops = {
.pg_init = ff_layout_pg_init_read,
.pg_test = pnfs_generic_pg_test,
.pg_doio = pnfs_generic_pg_readpages,
.pg_cleanup = pnfs_generic_pg_cleanup,
};
static const struct nfs_pageio_ops ff_layout_pg_write_ops = {
.pg_init = ff_layout_pg_init_write,
.pg_test = pnfs_generic_pg_test,
.pg_doio = pnfs_generic_pg_writepages,
.pg_get_mirror_count = ff_layout_pg_get_mirror_count_write,
.pg_cleanup = pnfs_generic_pg_cleanup,
};
static void ff_layout_reset_write(struct nfs_pgio_header *hdr, bool retry_pnfs)
{
struct rpc_task *task = &hdr->task;
pnfs_layoutcommit_inode(hdr->inode, false);
if (retry_pnfs) {
dprintk("%s Reset task %5u for i/o through pNFS "
"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
hdr->task.tk_pid,
hdr->inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(hdr->inode),
hdr->args.count,
(unsigned long long)hdr->args.offset);
hdr->completion_ops->reschedule_io(hdr);
return;
}
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
dprintk("%s Reset task %5u for i/o through MDS "
"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
hdr->task.tk_pid,
hdr->inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(hdr->inode),
hdr->args.count,
(unsigned long long)hdr->args.offset);
task->tk_status = pnfs_write_done_resend_to_mds(hdr);
}
}
static void ff_layout_reset_read(struct nfs_pgio_header *hdr)
{
struct rpc_task *task = &hdr->task;
pnfs_layoutcommit_inode(hdr->inode, false);
if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
dprintk("%s Reset task %5u for i/o through MDS "
"(req %s/%llu, %u bytes @ offset %llu)\n", __func__,
hdr->task.tk_pid,
hdr->inode->i_sb->s_id,
(unsigned long long)NFS_FILEID(hdr->inode),
hdr->args.count,
(unsigned long long)hdr->args.offset);
task->tk_status = pnfs_read_done_resend_to_mds(hdr);
}
}
static int ff_layout_async_handle_error_v4(struct rpc_task *task,
struct nfs4_state *state,
struct nfs_client *clp,
struct pnfs_layout_segment *lseg,
int idx)
{
struct pnfs_layout_hdr *lo = lseg->pls_layout;
struct inode *inode = lo->plh_inode;
struct nfs_server *mds_server = NFS_SERVER(inode);
struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
struct nfs_client *mds_client = mds_server->nfs_client;
struct nfs4_slot_table *tbl = &clp->cl_session->fc_slot_table;
if (task->tk_status >= 0)
return 0;
switch (task->tk_status) {
/* MDS state errors */
case -NFS4ERR_DELEG_REVOKED:
case -NFS4ERR_ADMIN_REVOKED:
case -NFS4ERR_BAD_STATEID:
if (state == NULL)
break;
nfs_remove_bad_delegation(state->inode);
case -NFS4ERR_OPENMODE:
if (state == NULL)
break;
if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
goto out_bad_stateid;
goto wait_on_recovery;
case -NFS4ERR_EXPIRED:
if (state != NULL) {
if (nfs4_schedule_stateid_recovery(mds_server, state) < 0)
goto out_bad_stateid;
}
nfs4_schedule_lease_recovery(mds_client);
goto wait_on_recovery;
/* DS session errors */
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_DEADSESSION:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
case -NFS4ERR_SEQ_FALSE_RETRY:
case -NFS4ERR_SEQ_MISORDERED:
dprintk("%s ERROR %d, Reset session. Exchangeid "
"flags 0x%x\n", __func__, task->tk_status,
clp->cl_exchange_flags);
nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
break;
case -NFS4ERR_DELAY:
case -NFS4ERR_GRACE:
rpc_delay(task, FF_LAYOUT_POLL_RETRY_MAX);
break;
case -NFS4ERR_RETRY_UNCACHED_REP:
break;
/* Invalidate Layout errors */
case -NFS4ERR_PNFS_NO_LAYOUT:
case -ESTALE: /* mapped NFS4ERR_STALE */
case -EBADHANDLE: /* mapped NFS4ERR_BADHANDLE */
case -EISDIR: /* mapped NFS4ERR_ISDIR */
case -NFS4ERR_FHEXPIRED:
case -NFS4ERR_WRONG_TYPE:
dprintk("%s Invalid layout error %d\n", __func__,
task->tk_status);
/*
* Destroy layout so new i/o will get a new layout.
* Layout will not be destroyed until all current lseg
* references are put. Mark layout as invalid to resend failed
* i/o and all i/o waiting on the slot table to the MDS until
* layout is destroyed and a new valid layout is obtained.
*/
pnfs_destroy_layout(NFS_I(inode));
rpc_wake_up(&tbl->slot_tbl_waitq);
goto reset;
/* RPC connection errors */
case -ECONNREFUSED:
case -EHOSTDOWN:
case -EHOSTUNREACH:
case -ENETUNREACH:
case -EIO:
case -ETIMEDOUT:
case -EPIPE:
dprintk("%s DS connection error %d\n", __func__,
task->tk_status);
nfs4_mark_deviceid_unavailable(devid);
rpc_wake_up(&tbl->slot_tbl_waitq);
/* fall through */
default:
if (ff_layout_no_fallback_to_mds(lseg) ||
ff_layout_has_available_ds(lseg))
return -NFS4ERR_RESET_TO_PNFS;
reset:
dprintk("%s Retry through MDS. Error %d\n", __func__,
task->tk_status);
return -NFS4ERR_RESET_TO_MDS;
}
out:
task->tk_status = 0;
return -EAGAIN;
out_bad_stateid:
task->tk_status = -EIO;
return 0;
wait_on_recovery:
rpc_sleep_on(&mds_client->cl_rpcwaitq, task, NULL);
if (test_bit(NFS4CLNT_MANAGER_RUNNING, &mds_client->cl_state) == 0)
rpc_wake_up_queued_task(&mds_client->cl_rpcwaitq, task);
goto out;
}
/* Retry all errors through either pNFS or MDS except for -EJUKEBOX */
static int ff_layout_async_handle_error_v3(struct rpc_task *task,
struct pnfs_layout_segment *lseg,
int idx)
{
struct nfs4_deviceid_node *devid = FF_LAYOUT_DEVID_NODE(lseg, idx);
if (task->tk_status >= 0)
return 0;
switch (task->tk_status) {
/* File access problems. Don't mark the device as unavailable */
case -EACCES:
case -ESTALE:
case -EISDIR:
case -EBADHANDLE:
case -ELOOP:
case -ENOSPC:
break;
case -EJUKEBOX:
nfs_inc_stats(lseg->pls_layout->plh_inode, NFSIOS_DELAY);
goto out_retry;
default:
dprintk("%s DS connection error %d\n", __func__,
task->tk_status);
nfs4_mark_deviceid_unavailable(devid);
}
/* FIXME: Need to prevent infinite looping here. */
return -NFS4ERR_RESET_TO_PNFS;
out_retry:
task->tk_status = 0;
rpc_restart_call_prepare(task);
rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
return -EAGAIN;
}
static int ff_layout_async_handle_error(struct rpc_task *task,
struct nfs4_state *state,
struct nfs_client *clp,
struct pnfs_layout_segment *lseg,
int idx)
{
int vers = clp->cl_nfs_mod->rpc_vers->number;
switch (vers) {
case 3:
return ff_layout_async_handle_error_v3(task, lseg, idx);
case 4:
return ff_layout_async_handle_error_v4(task, state, clp,
lseg, idx);
default:
/* should never happen */
WARN_ON_ONCE(1);
return 0;
}
}
static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
int idx, u64 offset, u64 length,
u32 status, int opnum, int error)
{
struct nfs4_ff_layout_mirror *mirror;
int err;
if (status == 0) {
switch (error) {
case -ETIMEDOUT:
case -EPFNOSUPPORT:
case -EPROTONOSUPPORT:
case -EOPNOTSUPP:
case -ECONNREFUSED:
case -ECONNRESET:
case -EHOSTDOWN:
case -EHOSTUNREACH:
case -ENETUNREACH:
case -EADDRINUSE:
case -ENOBUFS:
case -EPIPE:
case -EPERM:
status = NFS4ERR_NXIO;
break;
case -EACCES:
status = NFS4ERR_ACCESS;
break;
default:
return;
}
}
switch (status) {
case NFS4ERR_DELAY:
case NFS4ERR_GRACE:
return;
default:
break;
}
mirror = FF_LAYOUT_COMP(lseg, idx);
err = ff_layout_track_ds_error(FF_LAYOUT_FROM_HDR(lseg->pls_layout),
mirror, offset, length, status, opnum,
GFP_NOIO);
pnfs_error_mark_layout_for_return(lseg->pls_layout->plh_inode, lseg);
dprintk("%s: err %d op %d status %u\n", __func__, err, opnum, status);
}
/* NFS_PROTO call done callback routines */
static int ff_layout_read_done_cb(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
int err;
trace_nfs4_pnfs_read(hdr, task->tk_status);
if (task->tk_status < 0)
ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
hdr->args.offset, hdr->args.count,
hdr->res.op_status, OP_READ,
task->tk_status);
err = ff_layout_async_handle_error(task, hdr->args.context->state,
hdr->ds_clp, hdr->lseg,
hdr->pgio_mirror_idx);
switch (err) {
case -NFS4ERR_RESET_TO_PNFS:
if (ff_layout_choose_best_ds_for_read(hdr->lseg,
hdr->pgio_mirror_idx + 1,
&hdr->pgio_mirror_idx))
goto out_eagain;
set_bit(NFS_LAYOUT_RETURN_REQUESTED,
&hdr->lseg->pls_layout->plh_flags);
pnfs_read_resend_pnfs(hdr);
return task->tk_status;
case -NFS4ERR_RESET_TO_MDS:
ff_layout_reset_read(hdr);
return task->tk_status;
case -EAGAIN:
goto out_eagain;
}
return 0;
out_eagain:
rpc_restart_call_prepare(task);
return -EAGAIN;
}
static bool
ff_layout_need_layoutcommit(struct pnfs_layout_segment *lseg)
{
return !(FF_LAYOUT_LSEG(lseg)->flags & FF_FLAGS_NO_LAYOUTCOMMIT);
}
/*
* We reference the rpc_cred of the first WRITE that triggers the need for
* a LAYOUTCOMMIT, and use it to send the layoutcommit compound.
* rfc5661 is not clear about which credential should be used.
*
* Flexlayout client should treat DS replied FILE_SYNC as DATA_SYNC, so
* to follow http://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
* we always send layoutcommit after DS writes.
*/
static void
ff_layout_set_layoutcommit(struct nfs_pgio_header *hdr)
{
if (!ff_layout_need_layoutcommit(hdr->lseg))
return;
pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
hdr->mds_offset + hdr->res.count);
dprintk("%s inode %lu pls_end_pos %lu\n", __func__, hdr->inode->i_ino,
(unsigned long) NFS_I(hdr->inode)->layout->plh_lwb);
}
static bool
ff_layout_reset_to_mds(struct pnfs_layout_segment *lseg, int idx)
{
/* No mirroring for now */
struct nfs4_deviceid_node *node = FF_LAYOUT_DEVID_NODE(lseg, idx);
return ff_layout_test_devid_unavailable(node);
}
static void ff_layout_read_record_layoutstats_start(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
return;
nfs4_ff_layout_stat_io_start_read(hdr->inode,
FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
hdr->args.count,
task->tk_start);
}
static void ff_layout_read_record_layoutstats_done(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
return;
nfs4_ff_layout_stat_io_end_read(task,
FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
hdr->args.count,
hdr->res.count);
}
static int ff_layout_read_prepare_common(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
rpc_exit(task, -EIO);
return -EIO;
}
if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
dprintk("%s task %u reset io to MDS\n", __func__, task->tk_pid);
if (ff_layout_has_available_ds(hdr->lseg))
pnfs_read_resend_pnfs(hdr);
else
ff_layout_reset_read(hdr);
rpc_exit(task, 0);
return -EAGAIN;
}
hdr->pgio_done_cb = ff_layout_read_done_cb;
ff_layout_read_record_layoutstats_start(task, hdr);
return 0;
}
/*
* Call ops for the async read/write cases
* In the case of dense layouts, the offset needs to be reset to its
* original value.
*/
static void ff_layout_read_prepare_v3(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
if (ff_layout_read_prepare_common(task, hdr))
return;
rpc_call_start(task);
}
static int ff_layout_setup_sequence(struct nfs_client *ds_clp,
struct nfs4_sequence_args *args,
struct nfs4_sequence_res *res,
struct rpc_task *task)
{
if (ds_clp->cl_session)
return nfs41_setup_sequence(ds_clp->cl_session,
args,
res,
task);
return nfs40_setup_sequence(ds_clp->cl_slot_tbl,
args,
res,
task);
}
static void ff_layout_read_prepare_v4(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
if (ff_layout_setup_sequence(hdr->ds_clp,
&hdr->args.seq_args,
&hdr->res.seq_res,
task))
return;
if (ff_layout_read_prepare_common(task, hdr))
return;
if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
hdr->args.lock_context, FMODE_READ) == -EIO)
rpc_exit(task, -EIO); /* lost lock, terminate I/O */
}
static void ff_layout_read_call_done(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
dprintk("--> %s task->tk_status %d\n", __func__, task->tk_status);
if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
task->tk_status == 0) {
nfs4_sequence_done(task, &hdr->res.seq_res);
return;
}
/* Note this may cause RPC to be resent */
hdr->mds_ops->rpc_call_done(task, hdr);
}
static void ff_layout_read_count_stats(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
ff_layout_read_record_layoutstats_done(task, hdr);
rpc_count_iostats_metrics(task,
&NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_READ]);
}
static void ff_layout_read_release(void *data)
{
struct nfs_pgio_header *hdr = data;
ff_layout_read_record_layoutstats_done(&hdr->task, hdr);
pnfs_generic_rw_release(data);
}
static int ff_layout_write_done_cb(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
int err;
trace_nfs4_pnfs_write(hdr, task->tk_status);
if (task->tk_status < 0)
ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
hdr->args.offset, hdr->args.count,
hdr->res.op_status, OP_WRITE,
task->tk_status);
err = ff_layout_async_handle_error(task, hdr->args.context->state,
hdr->ds_clp, hdr->lseg,
hdr->pgio_mirror_idx);
switch (err) {
case -NFS4ERR_RESET_TO_PNFS:
ff_layout_reset_write(hdr, true);
return task->tk_status;
case -NFS4ERR_RESET_TO_MDS:
ff_layout_reset_write(hdr, false);
return task->tk_status;
case -EAGAIN:
return -EAGAIN;
}
if (hdr->res.verf->committed == NFS_FILE_SYNC ||
hdr->res.verf->committed == NFS_DATA_SYNC)
ff_layout_set_layoutcommit(hdr);
/* zero out fattr since we don't care DS attr at all */
hdr->fattr.valid = 0;
if (task->tk_status >= 0)
nfs_writeback_update_inode(hdr);
return 0;
}
static int ff_layout_commit_done_cb(struct rpc_task *task,
struct nfs_commit_data *data)
{
int err;
trace_nfs4_pnfs_commit_ds(data, task->tk_status);
if (task->tk_status < 0)
ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
data->args.offset, data->args.count,
data->res.op_status, OP_COMMIT,
task->tk_status);
err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
data->lseg, data->ds_commit_index);
switch (err) {
case -NFS4ERR_RESET_TO_PNFS:
pnfs_generic_prepare_to_resend_writes(data);
return -EAGAIN;
case -NFS4ERR_RESET_TO_MDS:
pnfs_generic_prepare_to_resend_writes(data);
return -EAGAIN;
case -EAGAIN:
rpc_restart_call_prepare(task);
return -EAGAIN;
}
if (data->verf.committed == NFS_UNSTABLE
&& ff_layout_need_layoutcommit(data->lseg))
pnfs_set_layoutcommit(data->inode, data->lseg, data->lwb);
return 0;
}
static void ff_layout_write_record_layoutstats_start(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (test_and_set_bit(NFS_IOHDR_STAT, &hdr->flags))
return;
nfs4_ff_layout_stat_io_start_write(hdr->inode,
FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
hdr->args.count,
task->tk_start);
}
static void ff_layout_write_record_layoutstats_done(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (!test_and_clear_bit(NFS_IOHDR_STAT, &hdr->flags))
return;
nfs4_ff_layout_stat_io_end_write(task,
FF_LAYOUT_COMP(hdr->lseg, hdr->pgio_mirror_idx),
hdr->args.count, hdr->res.count,
hdr->res.verf->committed);
}
static int ff_layout_write_prepare_common(struct rpc_task *task,
struct nfs_pgio_header *hdr)
{
if (unlikely(test_bit(NFS_CONTEXT_BAD, &hdr->args.context->flags))) {
rpc_exit(task, -EIO);
return -EIO;
}
if (ff_layout_reset_to_mds(hdr->lseg, hdr->pgio_mirror_idx)) {
bool retry_pnfs;
retry_pnfs = ff_layout_has_available_ds(hdr->lseg);
dprintk("%s task %u reset io to %s\n", __func__,
task->tk_pid, retry_pnfs ? "pNFS" : "MDS");
ff_layout_reset_write(hdr, retry_pnfs);
rpc_exit(task, 0);
return -EAGAIN;
}
ff_layout_write_record_layoutstats_start(task, hdr);
return 0;
}
static void ff_layout_write_prepare_v3(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
if (ff_layout_write_prepare_common(task, hdr))
return;
rpc_call_start(task);
}
static void ff_layout_write_prepare_v4(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
if (ff_layout_setup_sequence(hdr->ds_clp,
&hdr->args.seq_args,
&hdr->res.seq_res,
task))
return;
if (ff_layout_write_prepare_common(task, hdr))
return;
if (nfs4_set_rw_stateid(&hdr->args.stateid, hdr->args.context,
hdr->args.lock_context, FMODE_WRITE) == -EIO)
rpc_exit(task, -EIO); /* lost lock, terminate I/O */
}
static void ff_layout_write_call_done(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
if (test_bit(NFS_IOHDR_REDO, &hdr->flags) &&
task->tk_status == 0) {
nfs4_sequence_done(task, &hdr->res.seq_res);
return;
}
/* Note this may cause RPC to be resent */
hdr->mds_ops->rpc_call_done(task, hdr);
}
static void ff_layout_write_count_stats(struct rpc_task *task, void *data)
{
struct nfs_pgio_header *hdr = data;
ff_layout_write_record_layoutstats_done(task, hdr);
rpc_count_iostats_metrics(task,
&NFS_CLIENT(hdr->inode)->cl_metrics[NFSPROC4_CLNT_WRITE]);
}
static void ff_layout_write_release(void *data)
{
struct nfs_pgio_header *hdr = data;
ff_layout_write_record_layoutstats_done(&hdr->task, hdr);
pnfs_generic_rw_release(data);
}
static void ff_layout_commit_record_layoutstats_start(struct rpc_task *task,
struct nfs_commit_data *cdata)
{
if (test_and_set_bit(NFS_IOHDR_STAT, &cdata->flags))
return;
nfs4_ff_layout_stat_io_start_write(cdata->inode,
FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
0, task->tk_start);
}
static void ff_layout_commit_record_layoutstats_done(struct rpc_task *task,
struct nfs_commit_data *cdata)
{
struct nfs_page *req;
__u64 count = 0;
if (!test_and_clear_bit(NFS_IOHDR_STAT, &cdata->flags))
return;
if (task->tk_status == 0) {
list_for_each_entry(req, &cdata->pages, wb_list)
count += req->wb_bytes;
}
nfs4_ff_layout_stat_io_end_write(task,
FF_LAYOUT_COMP(cdata->lseg, cdata->ds_commit_index),
count, count, NFS_FILE_SYNC);
}
static void ff_layout_commit_prepare_common(struct rpc_task *task,
struct nfs_commit_data *cdata)
{
ff_layout_commit_record_layoutstats_start(task, cdata);
}
static void ff_layout_commit_prepare_v3(struct rpc_task *task, void *data)
{
ff_layout_commit_prepare_common(task, data);
rpc_call_start(task);
}
static void ff_layout_commit_prepare_v4(struct rpc_task *task, void *data)
{
struct nfs_commit_data *wdata = data;
if (ff_layout_setup_sequence(wdata->ds_clp,
&wdata->args.seq_args,
&wdata->res.seq_res,
task))
return;
ff_layout_commit_prepare_common(task, data);
}
static void ff_layout_commit_done(struct rpc_task *task, void *data)
{
pnfs_generic_write_commit_done(task, data);
}
static void ff_layout_commit_count_stats(struct rpc_task *task, void *data)
{
struct nfs_commit_data *cdata = data;
ff_layout_commit_record_layoutstats_done(task, cdata);
rpc_count_iostats_metrics(task,
&NFS_CLIENT(cdata->inode)->cl_metrics[NFSPROC4_CLNT_COMMIT]);
}
static void ff_layout_commit_release(void *data)
{
struct nfs_commit_data *cdata = data;
ff_layout_commit_record_layoutstats_done(&cdata->task, cdata);
pnfs_generic_commit_release(data);
}
static const struct rpc_call_ops ff_layout_read_call_ops_v3 = {
.rpc_call_prepare = ff_layout_read_prepare_v3,
.rpc_call_done = ff_layout_read_call_done,
.rpc_count_stats = ff_layout_read_count_stats,
.rpc_release = ff_layout_read_release,
};
static const struct rpc_call_ops ff_layout_read_call_ops_v4 = {
.rpc_call_prepare = ff_layout_read_prepare_v4,
.rpc_call_done = ff_layout_read_call_done,
.rpc_count_stats = ff_layout_read_count_stats,
.rpc_release = ff_layout_read_release,
};
static const struct rpc_call_ops ff_layout_write_call_ops_v3 = {
.rpc_call_prepare = ff_layout_write_prepare_v3,
.rpc_call_done = ff_layout_write_call_done,
.rpc_count_stats = ff_layout_write_count_stats,
.rpc_release = ff_layout_write_release,
};
static const struct rpc_call_ops ff_layout_write_call_ops_v4 = {
.rpc_call_prepare = ff_layout_write_prepare_v4,
.rpc_call_done = ff_layout_write_call_done,
.rpc_count_stats = ff_layout_write_count_stats,
.rpc_release = ff_layout_write_release,
};
static const struct rpc_call_ops ff_layout_commit_call_ops_v3 = {
.rpc_call_prepare = ff_layout_commit_prepare_v3,
.rpc_call_done = ff_layout_commit_done,
.rpc_count_stats = ff_layout_commit_count_stats,
.rpc_release = ff_layout_commit_release,
};
static const struct rpc_call_ops ff_layout_commit_call_ops_v4 = {
.rpc_call_prepare = ff_layout_commit_prepare_v4,
.rpc_call_done = ff_layout_commit_done,
.rpc_count_stats = ff_layout_commit_count_stats,
.rpc_release = ff_layout_commit_release,
};
static enum pnfs_try_status
ff_layout_read_pagelist(struct nfs_pgio_header *hdr)
{
struct pnfs_layout_segment *lseg = hdr->lseg;
struct nfs4_pnfs_ds *ds;
struct rpc_clnt *ds_clnt;
struct rpc_cred *ds_cred;
loff_t offset = hdr->args.offset;
u32 idx = hdr->pgio_mirror_idx;
int vers;
struct nfs_fh *fh;
dprintk("--> %s ino %lu pgbase %u req %Zu@%llu\n",
__func__, hdr->inode->i_ino,
hdr->args.pgbase, (size_t)hdr->args.count, offset);
ds = nfs4_ff_layout_prepare_ds(lseg, idx, false);
if (!ds)
goto out_failed;
ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
hdr->inode);
if (IS_ERR(ds_clnt))
goto out_failed;
ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
if (IS_ERR(ds_cred))
goto out_failed;
vers = nfs4_ff_layout_ds_version(lseg, idx);
dprintk("%s USE DS: %s cl_count %d vers %d\n", __func__,
ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count), vers);
atomic_inc(&ds->ds_clp->cl_count);
hdr->ds_clp = ds->ds_clp;
fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
if (fh)
hdr->args.fh = fh;
/*
* Note that if we ever decide to split across DSes,
* then we may need to handle dense-like offsets.
*/
hdr->args.offset = offset;
hdr->mds_offset = offset;
/* Perform an asynchronous read to ds */
nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
vers == 3 ? &ff_layout_read_call_ops_v3 :
&ff_layout_read_call_ops_v4,
0, RPC_TASK_SOFTCONN);
return PNFS_ATTEMPTED;
out_failed:
if (ff_layout_has_available_ds(lseg))
return PNFS_TRY_AGAIN;
return PNFS_NOT_ATTEMPTED;
}
/* Perform async writes. */
static enum pnfs_try_status
ff_layout_write_pagelist(struct nfs_pgio_header *hdr, int sync)
{
struct pnfs_layout_segment *lseg = hdr->lseg;
struct nfs4_pnfs_ds *ds;
struct rpc_clnt *ds_clnt;
struct rpc_cred *ds_cred;
loff_t offset = hdr->args.offset;
int vers;
struct nfs_fh *fh;
int idx = hdr->pgio_mirror_idx;
ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
if (!ds)
return PNFS_NOT_ATTEMPTED;
ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
hdr->inode);
if (IS_ERR(ds_clnt))
return PNFS_NOT_ATTEMPTED;
ds_cred = ff_layout_get_ds_cred(lseg, idx, hdr->cred);
if (IS_ERR(ds_cred))
return PNFS_NOT_ATTEMPTED;
vers = nfs4_ff_layout_ds_version(lseg, idx);
dprintk("%s ino %lu sync %d req %Zu@%llu DS: %s cl_count %d vers %d\n",
__func__, hdr->inode->i_ino, sync, (size_t) hdr->args.count,
offset, ds->ds_remotestr, atomic_read(&ds->ds_clp->cl_count),
vers);
hdr->pgio_done_cb = ff_layout_write_done_cb;
atomic_inc(&ds->ds_clp->cl_count);
hdr->ds_clp = ds->ds_clp;
hdr->ds_commit_idx = idx;
fh = nfs4_ff_layout_select_ds_fh(lseg, idx);
if (fh)
hdr->args.fh = fh;
/*
* Note that if we ever decide to split across DSes,
* then we may need to handle dense-like offsets.
*/
hdr->args.offset = offset;
/* Perform an asynchronous write */
nfs_initiate_pgio(ds_clnt, hdr, ds_cred, ds->ds_clp->rpc_ops,
vers == 3 ? &ff_layout_write_call_ops_v3 :
&ff_layout_write_call_ops_v4,
sync, RPC_TASK_SOFTCONN);
return PNFS_ATTEMPTED;
}
static u32 calc_ds_index_from_commit(struct pnfs_layout_segment *lseg, u32 i)
{
return i;
}
static struct nfs_fh *
select_ds_fh_from_commit(struct pnfs_layout_segment *lseg, u32 i)
{
struct nfs4_ff_layout_segment *flseg = FF_LAYOUT_LSEG(lseg);
/* FIXME: Assume that there is only one NFS version available
* for the DS.
*/
return &flseg->mirror_array[i]->fh_versions[0];
}
static int ff_layout_initiate_commit(struct nfs_commit_data *data, int how)
{
struct pnfs_layout_segment *lseg = data->lseg;
struct nfs4_pnfs_ds *ds;
struct rpc_clnt *ds_clnt;
struct rpc_cred *ds_cred;
u32 idx;
int vers;
struct nfs_fh *fh;
idx = calc_ds_index_from_commit(lseg, data->ds_commit_index);
ds = nfs4_ff_layout_prepare_ds(lseg, idx, true);
if (!ds)
goto out_err;
ds_clnt = nfs4_ff_find_or_create_ds_client(lseg, idx, ds->ds_clp,
data->inode);
if (IS_ERR(ds_clnt))
goto out_err;
ds_cred = ff_layout_get_ds_cred(lseg, idx, data->cred);
if (IS_ERR(ds_cred))
goto out_err;
vers = nfs4_ff_layout_ds_version(lseg, idx);
dprintk("%s ino %lu, how %d cl_count %d vers %d\n", __func__,
data->inode->i_ino, how, atomic_read(&ds->ds_clp->cl_count),
vers);
data->commit_done_cb = ff_layout_commit_done_cb;
data->cred = ds_cred;
atomic_inc(&ds->ds_clp->cl_count);
data->ds_clp = ds->ds_clp;
fh = select_ds_fh_from_commit(lseg, data->ds_commit_index);
if (fh)
data->args.fh = fh;
return nfs_initiate_commit(ds_clnt, data, ds->ds_clp->rpc_ops,
vers == 3 ? &ff_layout_commit_call_ops_v3 :
&ff_layout_commit_call_ops_v4,
how, RPC_TASK_SOFTCONN);
out_err:
pnfs_generic_prepare_to_resend_writes(data);
pnfs_generic_commit_release(data);
return -EAGAIN;
}
static int
ff_layout_commit_pagelist(struct inode *inode, struct list_head *mds_pages,
int how, struct nfs_commit_info *cinfo)
{
return pnfs_generic_commit_pagelist(inode, mds_pages, how, cinfo,
ff_layout_initiate_commit);
}
static struct pnfs_ds_commit_info *
ff_layout_get_ds_info(struct inode *inode)
{
struct pnfs_layout_hdr *layout = NFS_I(inode)->layout;
if (layout == NULL)
return NULL;
return &FF_LAYOUT_FROM_HDR(layout)->commit_info;
}
static void
ff_layout_free_deviceid_node(struct nfs4_deviceid_node *d)
{
nfs4_ff_layout_free_deviceid(container_of(d, struct nfs4_ff_layout_ds,
id_node));
}
static int ff_layout_encode_ioerr(struct nfs4_flexfile_layout *flo,
struct xdr_stream *xdr,
const struct nfs4_layoutreturn_args *args)
{
struct pnfs_layout_hdr *hdr = &flo->generic_hdr;
__be32 *start;
int count = 0, ret = 0;
start = xdr_reserve_space(xdr, 4);
if (unlikely(!start))
return -E2BIG;
/* This assume we always return _ALL_ layouts */
spin_lock(&hdr->plh_inode->i_lock);
ret = ff_layout_encode_ds_ioerr(flo, xdr, &count, &args->range);
spin_unlock(&hdr->plh_inode->i_lock);
*start = cpu_to_be32(count);
return ret;
}
/* report nothing for now */
static void ff_layout_encode_iostats(struct nfs4_flexfile_layout *flo,
struct xdr_stream *xdr,
const struct nfs4_layoutreturn_args *args)
{
__be32 *p;
p = xdr_reserve_space(xdr, 4);
if (likely(p))
*p = cpu_to_be32(0);
}
static struct nfs4_deviceid_node *
ff_layout_alloc_deviceid_node(struct nfs_server *server,
struct pnfs_device *pdev, gfp_t gfp_flags)
{
struct nfs4_ff_layout_ds *dsaddr;
dsaddr = nfs4_ff_alloc_deviceid_node(server, pdev, gfp_flags);
if (!dsaddr)
return NULL;
return &dsaddr->id_node;
}
static void
ff_layout_encode_layoutreturn(struct pnfs_layout_hdr *lo,
struct xdr_stream *xdr,
const struct nfs4_layoutreturn_args *args)
{
struct nfs4_flexfile_layout *flo = FF_LAYOUT_FROM_HDR(lo);
__be32 *start;
dprintk("%s: Begin\n", __func__);
start = xdr_reserve_space(xdr, 4);
BUG_ON(!start);
ff_layout_encode_ioerr(flo, xdr, args);
ff_layout_encode_iostats(flo, xdr, args);
*start = cpu_to_be32((xdr->p - start - 1) * 4);
dprintk("%s: Return\n", __func__);
}
static int
ff_layout_ntop4(const struct sockaddr *sap, char *buf, const size_t buflen)
{
const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
return snprintf(buf, buflen, "%pI4", &sin->sin_addr);
}
static size_t
ff_layout_ntop6_noscopeid(const struct sockaddr *sap, char *buf,
const int buflen)
{
const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
const struct in6_addr *addr = &sin6->sin6_addr;
/*
* RFC 4291, Section 2.2.2
*
* Shorthanded ANY address
*/
if (ipv6_addr_any(addr))
return snprintf(buf, buflen, "::");
/*
* RFC 4291, Section 2.2.2
*
* Shorthanded loopback address
*/
if (ipv6_addr_loopback(addr))
return snprintf(buf, buflen, "::1");
/*
* RFC 4291, Section 2.2.3
*
* Special presentation address format for mapped v4
* addresses.
*/
if (ipv6_addr_v4mapped(addr))
return snprintf(buf, buflen, "::ffff:%pI4",
&addr->s6_addr32[3]);
/*
* RFC 4291, Section 2.2.1
*/
return snprintf(buf, buflen, "%pI6c", addr);
}
/* Derived from rpc_sockaddr2uaddr */
static void
ff_layout_encode_netaddr(struct xdr_stream *xdr, struct nfs4_pnfs_ds_addr *da)
{
struct sockaddr *sap = (struct sockaddr *)&da->da_addr;
char portbuf[RPCBIND_MAXUADDRPLEN];
char addrbuf[RPCBIND_MAXUADDRLEN];
char *netid;
unsigned short port;
int len, netid_len;
__be32 *p;
switch (sap->sa_family) {
case AF_INET:
if (ff_layout_ntop4(sap, addrbuf, sizeof(addrbuf)) == 0)
return;
port = ntohs(((struct sockaddr_in *)sap)->sin_port);
netid = "tcp";
netid_len = 3;
break;
case AF_INET6:
if (ff_layout_ntop6_noscopeid(sap, addrbuf, sizeof(addrbuf)) == 0)
return;
port = ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
netid = "tcp6";
netid_len = 4;
break;
default:
/* we only support tcp and tcp6 */
WARN_ON_ONCE(1);
return;
}
snprintf(portbuf, sizeof(portbuf), ".%u.%u", port >> 8, port & 0xff);
len = strlcat(addrbuf, portbuf, sizeof(addrbuf));
p = xdr_reserve_space(xdr, 4 + netid_len);
xdr_encode_opaque(p, netid, netid_len);
p = xdr_reserve_space(xdr, 4 + len);
xdr_encode_opaque(p, addrbuf, len);
}
static void
ff_layout_encode_nfstime(struct xdr_stream *xdr,
ktime_t t)
{
struct timespec64 ts;
__be32 *p;
p = xdr_reserve_space(xdr, 12);
ts = ktime_to_timespec64(t);
p = xdr_encode_hyper(p, ts.tv_sec);
*p++ = cpu_to_be32(ts.tv_nsec);
}
static void
ff_layout_encode_io_latency(struct xdr_stream *xdr,
struct nfs4_ff_io_stat *stat)
{
__be32 *p;
p = xdr_reserve_space(xdr, 5 * 8);
p = xdr_encode_hyper(p, stat->ops_requested);
p = xdr_encode_hyper(p, stat->bytes_requested);
p = xdr_encode_hyper(p, stat->ops_completed);
p = xdr_encode_hyper(p, stat->bytes_completed);
p = xdr_encode_hyper(p, stat->bytes_not_delivered);
ff_layout_encode_nfstime(xdr, stat->total_busy_time);
ff_layout_encode_nfstime(xdr, stat->aggregate_completion_time);
}
static void
ff_layout_encode_layoutstats(struct xdr_stream *xdr,
struct nfs42_layoutstat_args *args,
struct nfs42_layoutstat_devinfo *devinfo)
{
struct nfs4_ff_layout_mirror *mirror = devinfo->layout_private;
struct nfs4_pnfs_ds_addr *da;
struct nfs4_pnfs_ds *ds = mirror->mirror_ds->ds;
struct nfs_fh *fh = &mirror->fh_versions[0];
__be32 *p, *start;
da = list_first_entry(&ds->ds_addrs, struct nfs4_pnfs_ds_addr, da_node);
dprintk("%s: DS %s: encoding address %s\n",
__func__, ds->ds_remotestr, da->da_remotestr);
/* layoutupdate length */
start = xdr_reserve_space(xdr, 4);
/* netaddr4 */
ff_layout_encode_netaddr(xdr, da);
/* nfs_fh4 */
p = xdr_reserve_space(xdr, 4 + fh->size);
xdr_encode_opaque(p, fh->data, fh->size);
/* ff_io_latency4 read */
spin_lock(&mirror->lock);
ff_layout_encode_io_latency(xdr, &mirror->read_stat.io_stat);
/* ff_io_latency4 write */
ff_layout_encode_io_latency(xdr, &mirror->write_stat.io_stat);
spin_unlock(&mirror->lock);
/* nfstime4 */
ff_layout_encode_nfstime(xdr, ktime_sub(ktime_get(), mirror->start_time));
/* bool */
p = xdr_reserve_space(xdr, 4);
*p = cpu_to_be32(false);
*start = cpu_to_be32((xdr->p - start - 1) * 4);
}
static int
ff_layout_mirror_prepare_stats(struct nfs42_layoutstat_args *args,
struct pnfs_layout_hdr *lo,
int dev_limit)
{
struct nfs4_flexfile_layout *ff_layout = FF_LAYOUT_FROM_HDR(lo);
struct nfs4_ff_layout_mirror *mirror;
struct nfs4_deviceid_node *dev;
struct nfs42_layoutstat_devinfo *devinfo;
int i = 0;
list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
if (i >= dev_limit)
break;
if (!mirror->mirror_ds)
continue;
/* mirror refcount put in cleanup_layoutstats */
if (!atomic_inc_not_zero(&mirror->ref))
continue;
dev = &mirror->mirror_ds->id_node;
devinfo = &args->devinfo[i];
memcpy(&devinfo->dev_id, &dev->deviceid, NFS4_DEVICEID4_SIZE);
devinfo->offset = 0;
devinfo->length = NFS4_MAX_UINT64;
devinfo->read_count = mirror->read_stat.io_stat.ops_completed;
devinfo->read_bytes = mirror->read_stat.io_stat.bytes_completed;
devinfo->write_count = mirror->write_stat.io_stat.ops_completed;
devinfo->write_bytes = mirror->write_stat.io_stat.bytes_completed;
devinfo->layout_type = LAYOUT_FLEX_FILES;
devinfo->layoutstats_encode = ff_layout_encode_layoutstats;
devinfo->layout_private = mirror;
i++;
}
return i;
}
static int
ff_layout_prepare_layoutstats(struct nfs42_layoutstat_args *args)
{
struct nfs4_flexfile_layout *ff_layout;
struct nfs4_ff_layout_mirror *mirror;
int dev_count = 0;
spin_lock(&args->inode->i_lock);
ff_layout = FF_LAYOUT_FROM_HDR(NFS_I(args->inode)->layout);
list_for_each_entry(mirror, &ff_layout->mirrors, mirrors) {
if (atomic_read(&mirror->ref) != 0)
dev_count ++;
}
spin_unlock(&args->inode->i_lock);
/* For now, send at most PNFS_LAYOUTSTATS_MAXDEV statistics */
if (dev_count > PNFS_LAYOUTSTATS_MAXDEV) {
dprintk("%s: truncating devinfo to limit (%d:%d)\n",
__func__, dev_count, PNFS_LAYOUTSTATS_MAXDEV);
dev_count = PNFS_LAYOUTSTATS_MAXDEV;
}
args->devinfo = kmalloc_array(dev_count, sizeof(*args->devinfo), GFP_NOIO);
if (!args->devinfo)
return -ENOMEM;
spin_lock(&args->inode->i_lock);
args->num_dev = ff_layout_mirror_prepare_stats(args,
&ff_layout->generic_hdr, dev_count);
spin_unlock(&args->inode->i_lock);
return 0;
}
static void
ff_layout_cleanup_layoutstats(struct nfs42_layoutstat_data *data)
{
struct nfs4_ff_layout_mirror *mirror;
int i;
for (i = 0; i < data->args.num_dev; i++) {
mirror = data->args.devinfo[i].layout_private;
data->args.devinfo[i].layout_private = NULL;
ff_layout_put_mirror(mirror);
}
}
static struct pnfs_layoutdriver_type flexfilelayout_type = {
.id = LAYOUT_FLEX_FILES,
.name = "LAYOUT_FLEX_FILES",
.owner = THIS_MODULE,
.alloc_layout_hdr = ff_layout_alloc_layout_hdr,
.free_layout_hdr = ff_layout_free_layout_hdr,
.alloc_lseg = ff_layout_alloc_lseg,
.free_lseg = ff_layout_free_lseg,
.add_lseg = ff_layout_add_lseg,
.pg_read_ops = &ff_layout_pg_read_ops,
.pg_write_ops = &ff_layout_pg_write_ops,
.get_ds_info = ff_layout_get_ds_info,
.free_deviceid_node = ff_layout_free_deviceid_node,
.mark_request_commit = pnfs_layout_mark_request_commit,
.clear_request_commit = pnfs_generic_clear_request_commit,
.scan_commit_lists = pnfs_generic_scan_commit_lists,
.recover_commit_reqs = pnfs_generic_recover_commit_reqs,
.commit_pagelist = ff_layout_commit_pagelist,
.read_pagelist = ff_layout_read_pagelist,
.write_pagelist = ff_layout_write_pagelist,
.alloc_deviceid_node = ff_layout_alloc_deviceid_node,
.encode_layoutreturn = ff_layout_encode_layoutreturn,
.sync = pnfs_nfs_generic_sync,
.prepare_layoutstats = ff_layout_prepare_layoutstats,
.cleanup_layoutstats = ff_layout_cleanup_layoutstats,
};
static int __init nfs4flexfilelayout_init(void)
{
printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Registering...\n",
__func__);
return pnfs_register_layoutdriver(&flexfilelayout_type);
}
static void __exit nfs4flexfilelayout_exit(void)
{
printk(KERN_INFO "%s: NFSv4 Flexfile Layout Driver Unregistering...\n",
__func__);
pnfs_unregister_layoutdriver(&flexfilelayout_type);
}
MODULE_ALIAS("nfs-layouttype4-4");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("The NFSv4 flexfile layout driver");
module_init(nfs4flexfilelayout_init);
module_exit(nfs4flexfilelayout_exit);