summaryrefslogtreecommitdiffstats
path: root/fs/nfs/pnfs.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/nfs/pnfs.c')
-rw-r--r--fs/nfs/pnfs.c352
1 files changed, 263 insertions, 89 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 38512bcd2e9..b8323aa7b54 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -395,6 +395,9 @@ mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
dprintk("%s:Begin lo %p\n", __func__, lo);
if (list_empty(&lo->plh_segs)) {
+ /* Reset MDS Threshold I/O counters */
+ NFS_I(lo->plh_inode)->write_io = 0;
+ NFS_I(lo->plh_inode)->read_io = 0;
if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
put_layout_hdr_locked(lo);
return 0;
@@ -455,6 +458,7 @@ pnfs_destroy_layout(struct nfs_inode *nfsi)
spin_unlock(&nfsi->vfs_inode.i_lock);
pnfs_free_lseg_list(&tmp_list);
}
+EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
/*
* Called by the state manger to remove all layouts established under an
@@ -692,6 +696,7 @@ out:
dprintk("<-- %s status: %d\n", __func__, status);
return status;
}
+EXPORT_SYMBOL_GPL(_pnfs_return_layout);
bool pnfs_roc(struct inode *ino)
{
@@ -931,6 +936,81 @@ pnfs_find_lseg(struct pnfs_layout_hdr *lo,
}
/*
+ * Use mdsthreshold hints set at each OPEN to determine if I/O should go
+ * to the MDS or over pNFS
+ *
+ * The nfs_inode read_io and write_io fields are cumulative counters reset
+ * when there are no layout segments. Note that in pnfs_update_layout iomode
+ * is set to IOMODE_READ for a READ request, and set to IOMODE_RW for a
+ * WRITE request.
+ *
+ * A return of true means use MDS I/O.
+ *
+ * From rfc 5661:
+ * If a file's size is smaller than the file size threshold, data accesses
+ * SHOULD be sent to the metadata server. If an I/O request has a length that
+ * is below the I/O size threshold, the I/O SHOULD be sent to the metadata
+ * server. If both file size and I/O size are provided, the client SHOULD
+ * reach or exceed both thresholds before sending its read or write
+ * requests to the data server.
+ */
+static bool pnfs_within_mdsthreshold(struct nfs_open_context *ctx,
+ struct inode *ino, int iomode)
+{
+ struct nfs4_threshold *t = ctx->mdsthreshold;
+ struct nfs_inode *nfsi = NFS_I(ino);
+ loff_t fsize = i_size_read(ino);
+ bool size = false, size_set = false, io = false, io_set = false, ret = false;
+
+ if (t == NULL)
+ return ret;
+
+ dprintk("%s bm=0x%x rd_sz=%llu wr_sz=%llu rd_io=%llu wr_io=%llu\n",
+ __func__, t->bm, t->rd_sz, t->wr_sz, t->rd_io_sz, t->wr_io_sz);
+
+ switch (iomode) {
+ case IOMODE_READ:
+ if (t->bm & THRESHOLD_RD) {
+ dprintk("%s fsize %llu\n", __func__, fsize);
+ size_set = true;
+ if (fsize < t->rd_sz)
+ size = true;
+ }
+ if (t->bm & THRESHOLD_RD_IO) {
+ dprintk("%s nfsi->read_io %llu\n", __func__,
+ nfsi->read_io);
+ io_set = true;
+ if (nfsi->read_io < t->rd_io_sz)
+ io = true;
+ }
+ break;
+ case IOMODE_RW:
+ if (t->bm & THRESHOLD_WR) {
+ dprintk("%s fsize %llu\n", __func__, fsize);
+ size_set = true;
+ if (fsize < t->wr_sz)
+ size = true;
+ }
+ if (t->bm & THRESHOLD_WR_IO) {
+ dprintk("%s nfsi->write_io %llu\n", __func__,
+ nfsi->write_io);
+ io_set = true;
+ if (nfsi->write_io < t->wr_io_sz)
+ io = true;
+ }
+ break;
+ }
+ if (size_set && io_set) {
+ if (size && io)
+ ret = true;
+ } else if (size || io)
+ ret = true;
+
+ dprintk("<-- %s size %d io %d ret %d\n", __func__, size, io, ret);
+ return ret;
+}
+
+/*
* Layout segment is retreived from the server if not cached.
* The appropriate layout segment is referenced and returned to the caller.
*/
@@ -957,6 +1037,10 @@ pnfs_update_layout(struct inode *ino,
if (!pnfs_enabled_sb(NFS_SERVER(ino)))
return NULL;
+
+ if (pnfs_within_mdsthreshold(ctx, ino, iomode))
+ return NULL;
+
spin_lock(&ino->i_lock);
lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
if (lo == NULL) {
@@ -1082,6 +1166,10 @@ pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *r
{
BUG_ON(pgio->pg_lseg != NULL);
+ if (req->wb_offset != req->wb_pgbase) {
+ nfs_pageio_reset_read_mds(pgio);
+ return;
+ }
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
req_offset(req),
@@ -1100,6 +1188,10 @@ pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *
{
BUG_ON(pgio->pg_lseg != NULL);
+ if (req->wb_offset != req->wb_pgbase) {
+ nfs_pageio_reset_write_mds(pgio);
+ return;
+ }
pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
req->wb_context,
req_offset(req),
@@ -1113,26 +1205,31 @@ pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *
EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
bool
-pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
+pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode,
+ const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_server *server = NFS_SERVER(inode);
struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
if (ld == NULL)
return false;
- nfs_pageio_init(pgio, inode, ld->pg_read_ops, server->rsize, 0);
+ nfs_pageio_init(pgio, inode, ld->pg_read_ops, compl_ops,
+ server->rsize, 0);
return true;
}
bool
-pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
+pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode,
+ int ioflags,
+ const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_server *server = NFS_SERVER(inode);
struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
if (ld == NULL)
return false;
- nfs_pageio_init(pgio, inode, ld->pg_write_ops, server->wsize, ioflags);
+ nfs_pageio_init(pgio, inode, ld->pg_write_ops, compl_ops,
+ server->wsize, ioflags);
return true;
}
@@ -1162,13 +1259,15 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
-static int pnfs_write_done_resend_to_mds(struct inode *inode, struct list_head *head)
+int pnfs_write_done_resend_to_mds(struct inode *inode,
+ struct list_head *head,
+ const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_pageio_descriptor pgio;
LIST_HEAD(failed);
/* Resend all requests through the MDS */
- nfs_pageio_init_write_mds(&pgio, inode, FLUSH_STABLE);
+ nfs_pageio_init_write_mds(&pgio, inode, FLUSH_STABLE, compl_ops);
while (!list_empty(head)) {
struct nfs_page *req = nfs_list_entry(head->next);
@@ -1188,30 +1287,37 @@ static int pnfs_write_done_resend_to_mds(struct inode *inode, struct list_head *
}
return 0;
}
+EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
+
+static void pnfs_ld_handle_write_error(struct nfs_write_data *data)
+{
+ struct nfs_pgio_header *hdr = data->header;
+
+ dprintk("pnfs write error = %d\n", hdr->pnfs_error);
+ if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
+ PNFS_LAYOUTRET_ON_ERROR) {
+ clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
+ pnfs_return_layout(hdr->inode);
+ }
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
+ data->task.tk_status = pnfs_write_done_resend_to_mds(hdr->inode,
+ &hdr->pages,
+ hdr->completion_ops);
+}
/*
* Called by non rpc-based layout drivers
*/
void pnfs_ld_write_done(struct nfs_write_data *data)
{
- if (likely(!data->pnfs_error)) {
+ struct nfs_pgio_header *hdr = data->header;
+
+ if (!hdr->pnfs_error) {
pnfs_set_layoutcommit(data);
- data->mds_ops->rpc_call_done(&data->task, data);
- } else {
- dprintk("pnfs write error = %d\n", data->pnfs_error);
- if (NFS_SERVER(data->inode)->pnfs_curr_ld->flags &
- PNFS_LAYOUTRET_ON_ERROR) {
- /* Don't lo_commit on error, Server will needs to
- * preform a file recovery.
- */
- clear_bit(NFS_INO_LAYOUTCOMMIT,
- &NFS_I(data->inode)->flags);
- pnfs_return_layout(data->inode);
- }
- data->task.tk_status = pnfs_write_done_resend_to_mds(data->inode, &data->pages);
- }
- put_lseg(data->lseg);
- data->mds_ops->rpc_release(data);
+ hdr->mds_ops->rpc_call_done(&data->task, data);
+ } else
+ pnfs_ld_handle_write_error(data);
+ hdr->mds_ops->rpc_release(data);
}
EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
@@ -1219,12 +1325,13 @@ static void
pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_write_data *data)
{
- list_splice_tail_init(&data->pages, &desc->pg_list);
- if (data->req && list_empty(&data->req->wb_list))
- nfs_list_add_request(data->req, &desc->pg_list);
- nfs_pageio_reset_write_mds(desc);
- desc->pg_recoalesce = 1;
- put_lseg(data->lseg);
+ struct nfs_pgio_header *hdr = data->header;
+
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+ list_splice_tail_init(&hdr->pages, &desc->pg_list);
+ nfs_pageio_reset_write_mds(desc);
+ desc->pg_recoalesce = 1;
+ }
nfs_writedata_release(data);
}
@@ -1234,23 +1341,18 @@ pnfs_try_to_write_data(struct nfs_write_data *wdata,
struct pnfs_layout_segment *lseg,
int how)
{
- struct inode *inode = wdata->inode;
+ struct nfs_pgio_header *hdr = wdata->header;
+ struct inode *inode = hdr->inode;
enum pnfs_try_status trypnfs;
struct nfs_server *nfss = NFS_SERVER(inode);
- wdata->mds_ops = call_ops;
- wdata->lseg = get_lseg(lseg);
+ hdr->mds_ops = call_ops;
dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
inode->i_ino, wdata->args.count, wdata->args.offset, how);
-
trypnfs = nfss->pnfs_curr_ld->write_pagelist(wdata, how);
- if (trypnfs == PNFS_NOT_ATTEMPTED) {
- put_lseg(wdata->lseg);
- wdata->lseg = NULL;
- } else
+ if (trypnfs != PNFS_NOT_ATTEMPTED)
nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
-
dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
return trypnfs;
}
@@ -1266,7 +1368,7 @@ pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *he
while (!list_empty(head)) {
enum pnfs_try_status trypnfs;
- data = list_entry(head->next, struct nfs_write_data, list);
+ data = list_first_entry(head, struct nfs_write_data, list);
list_del_init(&data->list);
trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
@@ -1276,43 +1378,82 @@ pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *he
put_lseg(lseg);
}
+static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
+{
+ put_lseg(hdr->lseg);
+ nfs_writehdr_free(hdr);
+}
+
int
pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
{
- LIST_HEAD(head);
+ struct nfs_write_header *whdr;
+ struct nfs_pgio_header *hdr;
int ret;
- ret = nfs_generic_flush(desc, &head);
- if (ret != 0) {
+ whdr = nfs_writehdr_alloc();
+ if (!whdr) {
+ desc->pg_completion_ops->error_cleanup(&desc->pg_list);
put_lseg(desc->pg_lseg);
desc->pg_lseg = NULL;
- return ret;
+ return -ENOMEM;
}
- pnfs_do_multiple_writes(desc, &head, desc->pg_ioflags);
- return 0;
+ hdr = &whdr->header;
+ nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
+ hdr->lseg = get_lseg(desc->pg_lseg);
+ atomic_inc(&hdr->refcnt);
+ ret = nfs_generic_flush(desc, hdr);
+ if (ret != 0) {
+ put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ } else
+ pnfs_do_multiple_writes(desc, &hdr->rpc_list, desc->pg_ioflags);
+ if (atomic_dec_and_test(&hdr->refcnt))
+ hdr->completion_ops->completion(hdr);
+ return ret;
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
-static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
+int pnfs_read_done_resend_to_mds(struct inode *inode,
+ struct list_head *head,
+ const struct nfs_pgio_completion_ops *compl_ops)
{
struct nfs_pageio_descriptor pgio;
+ LIST_HEAD(failed);
- put_lseg(data->lseg);
- data->lseg = NULL;
- dprintk("pnfs write error = %d\n", data->pnfs_error);
- if (NFS_SERVER(data->inode)->pnfs_curr_ld->flags &
- PNFS_LAYOUTRET_ON_ERROR)
- pnfs_return_layout(data->inode);
-
- nfs_pageio_init_read_mds(&pgio, data->inode);
-
- while (!list_empty(&data->pages)) {
- struct nfs_page *req = nfs_list_entry(data->pages.next);
+ /* Resend all requests through the MDS */
+ nfs_pageio_init_read_mds(&pgio, inode, compl_ops);
+ while (!list_empty(head)) {
+ struct nfs_page *req = nfs_list_entry(head->next);
nfs_list_remove_request(req);
- nfs_pageio_add_request(&pgio, req);
+ if (!nfs_pageio_add_request(&pgio, req))
+ nfs_list_add_request(req, &failed);
}
nfs_pageio_complete(&pgio);
+
+ if (!list_empty(&failed)) {
+ list_move(&failed, head);
+ return -EIO;
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
+
+static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
+{
+ struct nfs_pgio_header *hdr = data->header;
+
+ dprintk("pnfs read error = %d\n", hdr->pnfs_error);
+ if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
+ PNFS_LAYOUTRET_ON_ERROR) {
+ clear_bit(NFS_INO_LAYOUTCOMMIT, &NFS_I(hdr->inode)->flags);
+ pnfs_return_layout(hdr->inode);
+ }
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
+ data->task.tk_status = pnfs_read_done_resend_to_mds(hdr->inode,
+ &hdr->pages,
+ hdr->completion_ops);
}
/*
@@ -1320,13 +1461,14 @@ static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
*/
void pnfs_ld_read_done(struct nfs_read_data *data)
{
- if (likely(!data->pnfs_error)) {
+ struct nfs_pgio_header *hdr = data->header;
+
+ if (likely(!hdr->pnfs_error)) {
__nfs4_read_done_cb(data);
- data->mds_ops->rpc_call_done(&data->task, data);
+ hdr->mds_ops->rpc_call_done(&data->task, data);
} else
pnfs_ld_handle_read_error(data);
- put_lseg(data->lseg);
- data->mds_ops->rpc_release(data);
+ hdr->mds_ops->rpc_release(data);
}
EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
@@ -1334,11 +1476,13 @@ static void
pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
struct nfs_read_data *data)
{
- list_splice_tail_init(&data->pages, &desc->pg_list);
- if (data->req && list_empty(&data->req->wb_list))
- nfs_list_add_request(data->req, &desc->pg_list);
- nfs_pageio_reset_read_mds(desc);
- desc->pg_recoalesce = 1;
+ struct nfs_pgio_header *hdr = data->header;
+
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+ list_splice_tail_init(&hdr->pages, &desc->pg_list);
+ nfs_pageio_reset_read_mds(desc);
+ desc->pg_recoalesce = 1;
+ }
nfs_readdata_release(data);
}
@@ -1350,23 +1494,19 @@ pnfs_try_to_read_data(struct nfs_read_data *rdata,
const struct rpc_call_ops *call_ops,
struct pnfs_layout_segment *lseg)
{
- struct inode *inode = rdata->inode;
+ struct nfs_pgio_header *hdr = rdata->header;
+ struct inode *inode = hdr->inode;
struct nfs_server *nfss = NFS_SERVER(inode);
enum pnfs_try_status trypnfs;
- rdata->mds_ops = call_ops;
- rdata->lseg = get_lseg(lseg);
+ hdr->mds_ops = call_ops;
dprintk("%s: Reading ino:%lu %u@%llu\n",
__func__, inode->i_ino, rdata->args.count, rdata->args.offset);
trypnfs = nfss->pnfs_curr_ld->read_pagelist(rdata);
- if (trypnfs == PNFS_NOT_ATTEMPTED) {
- put_lseg(rdata->lseg);
- rdata->lseg = NULL;
- } else {
+ if (trypnfs != PNFS_NOT_ATTEMPTED)
nfs_inc_stats(inode, NFSIOS_PNFS_READ);
- }
dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
return trypnfs;
}
@@ -1382,7 +1522,7 @@ pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *hea
while (!list_empty(head)) {
enum pnfs_try_status trypnfs;
- data = list_entry(head->next, struct nfs_read_data, list);
+ data = list_first_entry(head, struct nfs_read_data, list);
list_del_init(&data->list);
trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
@@ -1392,20 +1532,40 @@ pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *hea
put_lseg(lseg);
}
+static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
+{
+ put_lseg(hdr->lseg);
+ nfs_readhdr_free(hdr);
+}
+
int
pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
{
- LIST_HEAD(head);
+ struct nfs_read_header *rhdr;
+ struct nfs_pgio_header *hdr;
int ret;
- ret = nfs_generic_pagein(desc, &head);
- if (ret != 0) {
+ rhdr = nfs_readhdr_alloc();
+ if (!rhdr) {
+ desc->pg_completion_ops->error_cleanup(&desc->pg_list);
+ ret = -ENOMEM;
put_lseg(desc->pg_lseg);
desc->pg_lseg = NULL;
return ret;
}
- pnfs_do_multiple_reads(desc, &head);
- return 0;
+ hdr = &rhdr->header;
+ nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
+ hdr->lseg = get_lseg(desc->pg_lseg);
+ atomic_inc(&hdr->refcnt);
+ ret = nfs_generic_pagein(desc, hdr);
+ if (ret != 0) {
+ put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ } else
+ pnfs_do_multiple_reads(desc, &hdr->rpc_list);
+ if (atomic_dec_and_test(&hdr->refcnt))
+ hdr->completion_ops->completion(hdr);
+ return ret;
}
EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
@@ -1438,30 +1598,32 @@ EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
void
pnfs_set_layoutcommit(struct nfs_write_data *wdata)
{
- struct nfs_inode *nfsi = NFS_I(wdata->inode);
+ struct nfs_pgio_header *hdr = wdata->header;
+ struct inode *inode = hdr->inode;
+ struct nfs_inode *nfsi = NFS_I(inode);
loff_t end_pos = wdata->mds_offset + wdata->res.count;
bool mark_as_dirty = false;
- spin_lock(&nfsi->vfs_inode.i_lock);
+ spin_lock(&inode->i_lock);
if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
mark_as_dirty = true;
dprintk("%s: Set layoutcommit for inode %lu ",
- __func__, wdata->inode->i_ino);
+ __func__, inode->i_ino);
}
- if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) {
+ if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &hdr->lseg->pls_flags)) {
/* references matched in nfs4_layoutcommit_release */
- get_lseg(wdata->lseg);
+ get_lseg(hdr->lseg);
}
if (end_pos > nfsi->layout->plh_lwb)
nfsi->layout->plh_lwb = end_pos;
- spin_unlock(&nfsi->vfs_inode.i_lock);
+ spin_unlock(&inode->i_lock);
dprintk("%s: lseg %p end_pos %llu\n",
- __func__, wdata->lseg, nfsi->layout->plh_lwb);
+ __func__, hdr->lseg, nfsi->layout->plh_lwb);
/* if pnfs_layoutcommit_inode() runs between inode locks, the next one
* will be a noop because NFS_INO_LAYOUTCOMMIT will not be set */
if (mark_as_dirty)
- mark_inode_dirty_sync(wdata->inode);
+ mark_inode_dirty_sync(inode);
}
EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
@@ -1550,3 +1712,15 @@ out_free:
kfree(data);
goto out;
}
+
+struct nfs4_threshold *pnfs_mdsthreshold_alloc(void)
+{
+ struct nfs4_threshold *thp;
+
+ thp = kzalloc(sizeof(*thp), GFP_NOFS);
+ if (!thp) {
+ dprintk("%s mdsthreshold allocation failed\n", __func__);
+ return NULL;
+ }
+ return thp;
+}