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-rw-r--r--fs/nfs/pnfs.c1552
1 files changed, 1552 insertions, 0 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
new file mode 100644
index 00000000..38512bcd
--- /dev/null
+++ b/fs/nfs/pnfs.c
@@ -0,0 +1,1552 @@
+/*
+ * pNFS functions to call and manage layout drivers.
+ *
+ * Copyright (c) 2002 [year of first publication]
+ * The Regents of the University of Michigan
+ * All Rights Reserved
+ *
+ * Dean Hildebrand <dhildebz@umich.edu>
+ *
+ * Permission is granted to use, copy, create derivative works, and
+ * redistribute this software and such derivative works for any purpose,
+ * so long as the name of the University of Michigan is not used in
+ * any advertising or publicity pertaining to the use or distribution
+ * of this software without specific, written prior authorization. If
+ * the above copyright notice or any other identification of the
+ * University of Michigan is included in any copy of any portion of
+ * this software, then the disclaimer below must also be included.
+ *
+ * This software is provided as is, without representation or warranty
+ * of any kind either express or implied, including without limitation
+ * the implied warranties of merchantability, fitness for a particular
+ * purpose, or noninfringement. The Regents of the University of
+ * Michigan shall not be liable for any damages, including special,
+ * indirect, incidental, or consequential damages, with respect to any
+ * claim arising out of or in connection with the use of the software,
+ * even if it has been or is hereafter advised of the possibility of
+ * such damages.
+ */
+
+#include <linux/nfs_fs.h>
+#include <linux/nfs_page.h>
+#include <linux/module.h>
+#include "internal.h"
+#include "pnfs.h"
+#include "iostat.h"
+
+#define NFSDBG_FACILITY NFSDBG_PNFS
+
+/* Locking:
+ *
+ * pnfs_spinlock:
+ * protects pnfs_modules_tbl.
+ */
+static DEFINE_SPINLOCK(pnfs_spinlock);
+
+/*
+ * pnfs_modules_tbl holds all pnfs modules
+ */
+static LIST_HEAD(pnfs_modules_tbl);
+
+/* Return the registered pnfs layout driver module matching given id */
+static struct pnfs_layoutdriver_type *
+find_pnfs_driver_locked(u32 id)
+{
+ struct pnfs_layoutdriver_type *local;
+
+ list_for_each_entry(local, &pnfs_modules_tbl, pnfs_tblid)
+ if (local->id == id)
+ goto out;
+ local = NULL;
+out:
+ dprintk("%s: Searching for id %u, found %p\n", __func__, id, local);
+ return local;
+}
+
+static struct pnfs_layoutdriver_type *
+find_pnfs_driver(u32 id)
+{
+ struct pnfs_layoutdriver_type *local;
+
+ spin_lock(&pnfs_spinlock);
+ local = find_pnfs_driver_locked(id);
+ spin_unlock(&pnfs_spinlock);
+ return local;
+}
+
+void
+unset_pnfs_layoutdriver(struct nfs_server *nfss)
+{
+ if (nfss->pnfs_curr_ld) {
+ if (nfss->pnfs_curr_ld->clear_layoutdriver)
+ nfss->pnfs_curr_ld->clear_layoutdriver(nfss);
+ module_put(nfss->pnfs_curr_ld->owner);
+ }
+ nfss->pnfs_curr_ld = NULL;
+}
+
+/*
+ * Try to set the server's pnfs module to the pnfs layout type specified by id.
+ * Currently only one pNFS layout driver per filesystem is supported.
+ *
+ * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
+ */
+void
+set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
+ u32 id)
+{
+ struct pnfs_layoutdriver_type *ld_type = NULL;
+
+ if (id == 0)
+ goto out_no_driver;
+ if (!(server->nfs_client->cl_exchange_flags &
+ (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
+ printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
+ __func__, id, server->nfs_client->cl_exchange_flags);
+ goto out_no_driver;
+ }
+ ld_type = find_pnfs_driver(id);
+ if (!ld_type) {
+ request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
+ ld_type = find_pnfs_driver(id);
+ if (!ld_type) {
+ dprintk("%s: No pNFS module found for %u.\n",
+ __func__, id);
+ goto out_no_driver;
+ }
+ }
+ if (!try_module_get(ld_type->owner)) {
+ dprintk("%s: Could not grab reference on module\n", __func__);
+ goto out_no_driver;
+ }
+ server->pnfs_curr_ld = ld_type;
+ if (ld_type->set_layoutdriver
+ && ld_type->set_layoutdriver(server, mntfh)) {
+ printk(KERN_ERR "NFS: %s: Error initializing pNFS layout "
+ "driver %u.\n", __func__, id);
+ module_put(ld_type->owner);
+ goto out_no_driver;
+ }
+
+ dprintk("%s: pNFS module for %u set\n", __func__, id);
+ return;
+
+out_no_driver:
+ dprintk("%s: Using NFSv4 I/O\n", __func__);
+ server->pnfs_curr_ld = NULL;
+}
+
+int
+pnfs_register_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
+{
+ int status = -EINVAL;
+ struct pnfs_layoutdriver_type *tmp;
+
+ if (ld_type->id == 0) {
+ printk(KERN_ERR "NFS: %s id 0 is reserved\n", __func__);
+ return status;
+ }
+ if (!ld_type->alloc_lseg || !ld_type->free_lseg) {
+ printk(KERN_ERR "NFS: %s Layout driver must provide "
+ "alloc_lseg and free_lseg.\n", __func__);
+ return status;
+ }
+
+ spin_lock(&pnfs_spinlock);
+ tmp = find_pnfs_driver_locked(ld_type->id);
+ if (!tmp) {
+ list_add(&ld_type->pnfs_tblid, &pnfs_modules_tbl);
+ status = 0;
+ dprintk("%s Registering id:%u name:%s\n", __func__, ld_type->id,
+ ld_type->name);
+ } else {
+ printk(KERN_ERR "NFS: %s Module with id %d already loaded!\n",
+ __func__, ld_type->id);
+ }
+ spin_unlock(&pnfs_spinlock);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(pnfs_register_layoutdriver);
+
+void
+pnfs_unregister_layoutdriver(struct pnfs_layoutdriver_type *ld_type)
+{
+ dprintk("%s Deregistering id:%u\n", __func__, ld_type->id);
+ spin_lock(&pnfs_spinlock);
+ list_del(&ld_type->pnfs_tblid);
+ spin_unlock(&pnfs_spinlock);
+}
+EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
+
+/*
+ * pNFS client layout cache
+ */
+
+/* Need to hold i_lock if caller does not already hold reference */
+void
+get_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ atomic_inc(&lo->plh_refcount);
+}
+
+static struct pnfs_layout_hdr *
+pnfs_alloc_layout_hdr(struct inode *ino, gfp_t gfp_flags)
+{
+ struct pnfs_layoutdriver_type *ld = NFS_SERVER(ino)->pnfs_curr_ld;
+ return ld->alloc_layout_hdr ? ld->alloc_layout_hdr(ino, gfp_flags) :
+ kzalloc(sizeof(struct pnfs_layout_hdr), gfp_flags);
+}
+
+static void
+pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ struct pnfs_layoutdriver_type *ld = NFS_SERVER(lo->plh_inode)->pnfs_curr_ld;
+ put_rpccred(lo->plh_lc_cred);
+ return ld->alloc_layout_hdr ? ld->free_layout_hdr(lo) : kfree(lo);
+}
+
+static void
+destroy_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ dprintk("%s: freeing layout cache %p\n", __func__, lo);
+ BUG_ON(!list_empty(&lo->plh_layouts));
+ NFS_I(lo->plh_inode)->layout = NULL;
+ pnfs_free_layout_hdr(lo);
+}
+
+static void
+put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
+{
+ if (atomic_dec_and_test(&lo->plh_refcount))
+ destroy_layout_hdr(lo);
+}
+
+void
+put_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ struct inode *inode = lo->plh_inode;
+
+ if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
+ destroy_layout_hdr(lo);
+ spin_unlock(&inode->i_lock);
+ }
+}
+
+static void
+init_lseg(struct pnfs_layout_hdr *lo, struct pnfs_layout_segment *lseg)
+{
+ INIT_LIST_HEAD(&lseg->pls_list);
+ INIT_LIST_HEAD(&lseg->pls_lc_list);
+ atomic_set(&lseg->pls_refcount, 1);
+ smp_mb();
+ set_bit(NFS_LSEG_VALID, &lseg->pls_flags);
+ lseg->pls_layout = lo;
+}
+
+static void free_lseg(struct pnfs_layout_segment *lseg)
+{
+ struct inode *ino = lseg->pls_layout->plh_inode;
+
+ NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
+ /* Matched by get_layout_hdr in pnfs_insert_layout */
+ put_layout_hdr(NFS_I(ino)->layout);
+}
+
+static void
+put_lseg_common(struct pnfs_layout_segment *lseg)
+{
+ struct inode *inode = lseg->pls_layout->plh_inode;
+
+ WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
+ list_del_init(&lseg->pls_list);
+ if (list_empty(&lseg->pls_layout->plh_segs)) {
+ set_bit(NFS_LAYOUT_DESTROYED, &lseg->pls_layout->plh_flags);
+ /* Matched by initial refcount set in alloc_init_layout_hdr */
+ put_layout_hdr_locked(lseg->pls_layout);
+ }
+ rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
+}
+
+void
+put_lseg(struct pnfs_layout_segment *lseg)
+{
+ struct inode *inode;
+
+ if (!lseg)
+ return;
+
+ dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
+ atomic_read(&lseg->pls_refcount),
+ test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
+ inode = lseg->pls_layout->plh_inode;
+ if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
+ LIST_HEAD(free_me);
+
+ put_lseg_common(lseg);
+ list_add(&lseg->pls_list, &free_me);
+ spin_unlock(&inode->i_lock);
+ pnfs_free_lseg_list(&free_me);
+ }
+}
+EXPORT_SYMBOL_GPL(put_lseg);
+
+static inline u64
+end_offset(u64 start, u64 len)
+{
+ u64 end;
+
+ end = start + len;
+ return end >= start ? end : NFS4_MAX_UINT64;
+}
+
+/* last octet in a range */
+static inline u64
+last_byte_offset(u64 start, u64 len)
+{
+ u64 end;
+
+ BUG_ON(!len);
+ end = start + len;
+ return end > start ? end - 1 : NFS4_MAX_UINT64;
+}
+
+/*
+ * is l2 fully contained in l1?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static inline int
+lo_seg_contained(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
+{
+ u64 start1 = l1->offset;
+ u64 end1 = end_offset(start1, l1->length);
+ u64 start2 = l2->offset;
+ u64 end2 = end_offset(start2, l2->length);
+
+ return (start1 <= start2) && (end1 >= end2);
+}
+
+/*
+ * is l1 and l2 intersecting?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static inline int
+lo_seg_intersecting(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
+{
+ u64 start1 = l1->offset;
+ u64 end1 = end_offset(start1, l1->length);
+ u64 start2 = l2->offset;
+ u64 end2 = end_offset(start2, l2->length);
+
+ return (end1 == NFS4_MAX_UINT64 || end1 > start2) &&
+ (end2 == NFS4_MAX_UINT64 || end2 > start1);
+}
+
+static bool
+should_free_lseg(struct pnfs_layout_range *lseg_range,
+ struct pnfs_layout_range *recall_range)
+{
+ return (recall_range->iomode == IOMODE_ANY ||
+ lseg_range->iomode == recall_range->iomode) &&
+ lo_seg_intersecting(lseg_range, recall_range);
+}
+
+/* Returns 1 if lseg is removed from list, 0 otherwise */
+static int mark_lseg_invalid(struct pnfs_layout_segment *lseg,
+ struct list_head *tmp_list)
+{
+ int rv = 0;
+
+ if (test_and_clear_bit(NFS_LSEG_VALID, &lseg->pls_flags)) {
+ /* Remove the reference keeping the lseg in the
+ * list. It will now be removed when all
+ * outstanding io is finished.
+ */
+ dprintk("%s: lseg %p ref %d\n", __func__, lseg,
+ atomic_read(&lseg->pls_refcount));
+ if (atomic_dec_and_test(&lseg->pls_refcount)) {
+ put_lseg_common(lseg);
+ list_add(&lseg->pls_list, tmp_list);
+ rv = 1;
+ }
+ }
+ return rv;
+}
+
+/* Returns count of number of matching invalid lsegs remaining in list
+ * after call.
+ */
+int
+mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
+ struct list_head *tmp_list,
+ struct pnfs_layout_range *recall_range)
+{
+ struct pnfs_layout_segment *lseg, *next;
+ int invalid = 0, removed = 0;
+
+ dprintk("%s:Begin lo %p\n", __func__, lo);
+
+ if (list_empty(&lo->plh_segs)) {
+ if (!test_and_set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags))
+ put_layout_hdr_locked(lo);
+ return 0;
+ }
+ list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
+ if (!recall_range ||
+ should_free_lseg(&lseg->pls_range, recall_range)) {
+ dprintk("%s: freeing lseg %p iomode %d "
+ "offset %llu length %llu\n", __func__,
+ lseg, lseg->pls_range.iomode, lseg->pls_range.offset,
+ lseg->pls_range.length);
+ invalid++;
+ removed += mark_lseg_invalid(lseg, tmp_list);
+ }
+ dprintk("%s:Return %i\n", __func__, invalid - removed);
+ return invalid - removed;
+}
+
+/* note free_me must contain lsegs from a single layout_hdr */
+void
+pnfs_free_lseg_list(struct list_head *free_me)
+{
+ struct pnfs_layout_segment *lseg, *tmp;
+ struct pnfs_layout_hdr *lo;
+
+ if (list_empty(free_me))
+ return;
+
+ lo = list_first_entry(free_me, struct pnfs_layout_segment,
+ pls_list)->pls_layout;
+
+ if (test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags)) {
+ struct nfs_client *clp;
+
+ clp = NFS_SERVER(lo->plh_inode)->nfs_client;
+ spin_lock(&clp->cl_lock);
+ list_del_init(&lo->plh_layouts);
+ spin_unlock(&clp->cl_lock);
+ }
+ list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
+ list_del(&lseg->pls_list);
+ free_lseg(lseg);
+ }
+}
+
+void
+pnfs_destroy_layout(struct nfs_inode *nfsi)
+{
+ struct pnfs_layout_hdr *lo;
+ LIST_HEAD(tmp_list);
+
+ spin_lock(&nfsi->vfs_inode.i_lock);
+ lo = nfsi->layout;
+ if (lo) {
+ lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
+ mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
+ }
+ spin_unlock(&nfsi->vfs_inode.i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+}
+
+/*
+ * Called by the state manger to remove all layouts established under an
+ * expired lease.
+ */
+void
+pnfs_destroy_all_layouts(struct nfs_client *clp)
+{
+ struct nfs_server *server;
+ struct pnfs_layout_hdr *lo;
+ LIST_HEAD(tmp_list);
+
+ nfs4_deviceid_mark_client_invalid(clp);
+ nfs4_deviceid_purge_client(clp);
+
+ spin_lock(&clp->cl_lock);
+ rcu_read_lock();
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ if (!list_empty(&server->layouts))
+ list_splice_init(&server->layouts, &tmp_list);
+ }
+ rcu_read_unlock();
+ spin_unlock(&clp->cl_lock);
+
+ while (!list_empty(&tmp_list)) {
+ lo = list_entry(tmp_list.next, struct pnfs_layout_hdr,
+ plh_layouts);
+ dprintk("%s freeing layout for inode %lu\n", __func__,
+ lo->plh_inode->i_ino);
+ list_del_init(&lo->plh_layouts);
+ pnfs_destroy_layout(NFS_I(lo->plh_inode));
+ }
+}
+
+/* update lo->plh_stateid with new if is more recent */
+void
+pnfs_set_layout_stateid(struct pnfs_layout_hdr *lo, const nfs4_stateid *new,
+ bool update_barrier)
+{
+ u32 oldseq, newseq;
+
+ oldseq = be32_to_cpu(lo->plh_stateid.seqid);
+ newseq = be32_to_cpu(new->seqid);
+ if ((int)(newseq - oldseq) > 0) {
+ nfs4_stateid_copy(&lo->plh_stateid, new);
+ if (update_barrier) {
+ u32 new_barrier = be32_to_cpu(new->seqid);
+
+ if ((int)(new_barrier - lo->plh_barrier))
+ lo->plh_barrier = new_barrier;
+ } else {
+ /* Because of wraparound, we want to keep the barrier
+ * "close" to the current seqids. It needs to be
+ * within 2**31 to count as "behind", so if it
+ * gets too near that limit, give us a litle leeway
+ * and bring it to within 2**30.
+ * NOTE - and yes, this is all unsigned arithmetic.
+ */
+ if (unlikely((newseq - lo->plh_barrier) > (3 << 29)))
+ lo->plh_barrier = newseq - (1 << 30);
+ }
+ }
+}
+
+/* lget is set to 1 if called from inside send_layoutget call chain */
+static bool
+pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
+ int lget)
+{
+ if ((stateid) &&
+ (int)(lo->plh_barrier - be32_to_cpu(stateid->seqid)) >= 0)
+ return true;
+ return lo->plh_block_lgets ||
+ test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
+ test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
+ (list_empty(&lo->plh_segs) &&
+ (atomic_read(&lo->plh_outstanding) > lget));
+}
+
+int
+pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
+ struct nfs4_state *open_state)
+{
+ int status = 0;
+
+ dprintk("--> %s\n", __func__);
+ spin_lock(&lo->plh_inode->i_lock);
+ if (pnfs_layoutgets_blocked(lo, NULL, 1)) {
+ status = -EAGAIN;
+ } else if (list_empty(&lo->plh_segs)) {
+ int seq;
+
+ do {
+ seq = read_seqbegin(&open_state->seqlock);
+ nfs4_stateid_copy(dst, &open_state->stateid);
+ } while (read_seqretry(&open_state->seqlock, seq));
+ } else
+ nfs4_stateid_copy(dst, &lo->plh_stateid);
+ spin_unlock(&lo->plh_inode->i_lock);
+ dprintk("<-- %s\n", __func__);
+ return status;
+}
+
+/*
+* Get layout from server.
+* for now, assume that whole file layouts are requested.
+* arg->offset: 0
+* arg->length: all ones
+*/
+static struct pnfs_layout_segment *
+send_layoutget(struct pnfs_layout_hdr *lo,
+ struct nfs_open_context *ctx,
+ struct pnfs_layout_range *range,
+ gfp_t gfp_flags)
+{
+ struct inode *ino = lo->plh_inode;
+ struct nfs_server *server = NFS_SERVER(ino);
+ struct nfs4_layoutget *lgp;
+ struct pnfs_layout_segment *lseg = NULL;
+ struct page **pages = NULL;
+ int i;
+ u32 max_resp_sz, max_pages;
+
+ dprintk("--> %s\n", __func__);
+
+ BUG_ON(ctx == NULL);
+ lgp = kzalloc(sizeof(*lgp), gfp_flags);
+ if (lgp == NULL)
+ return NULL;
+
+ /* allocate pages for xdr post processing */
+ max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
+ max_pages = nfs_page_array_len(0, max_resp_sz);
+
+ pages = kcalloc(max_pages, sizeof(struct page *), gfp_flags);
+ if (!pages)
+ goto out_err_free;
+
+ for (i = 0; i < max_pages; i++) {
+ pages[i] = alloc_page(gfp_flags);
+ if (!pages[i])
+ goto out_err_free;
+ }
+
+ lgp->args.minlength = PAGE_CACHE_SIZE;
+ if (lgp->args.minlength > range->length)
+ lgp->args.minlength = range->length;
+ lgp->args.maxcount = PNFS_LAYOUT_MAXSIZE;
+ lgp->args.range = *range;
+ lgp->args.type = server->pnfs_curr_ld->id;
+ lgp->args.inode = ino;
+ lgp->args.ctx = get_nfs_open_context(ctx);
+ lgp->args.layout.pages = pages;
+ lgp->args.layout.pglen = max_pages * PAGE_SIZE;
+ lgp->lsegpp = &lseg;
+ lgp->gfp_flags = gfp_flags;
+
+ /* Synchronously retrieve layout information from server and
+ * store in lseg.
+ */
+ nfs4_proc_layoutget(lgp);
+ if (!lseg) {
+ /* remember that LAYOUTGET failed and suspend trying */
+ set_bit(lo_fail_bit(range->iomode), &lo->plh_flags);
+ }
+
+ /* free xdr pages */
+ for (i = 0; i < max_pages; i++)
+ __free_page(pages[i]);
+ kfree(pages);
+
+ return lseg;
+
+out_err_free:
+ /* free any allocated xdr pages, lgp as it's not used */
+ if (pages) {
+ for (i = 0; i < max_pages; i++) {
+ if (!pages[i])
+ break;
+ __free_page(pages[i]);
+ }
+ kfree(pages);
+ }
+ kfree(lgp);
+ return NULL;
+}
+
+/* Initiates a LAYOUTRETURN(FILE) */
+int
+_pnfs_return_layout(struct inode *ino)
+{
+ struct pnfs_layout_hdr *lo = NULL;
+ struct nfs_inode *nfsi = NFS_I(ino);
+ LIST_HEAD(tmp_list);
+ struct nfs4_layoutreturn *lrp;
+ nfs4_stateid stateid;
+ int status = 0;
+
+ dprintk("--> %s\n", __func__);
+
+ spin_lock(&ino->i_lock);
+ lo = nfsi->layout;
+ if (!lo) {
+ spin_unlock(&ino->i_lock);
+ dprintk("%s: no layout to return\n", __func__);
+ return status;
+ }
+ stateid = nfsi->layout->plh_stateid;
+ /* Reference matched in nfs4_layoutreturn_release */
+ get_layout_hdr(lo);
+ mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
+ lo->plh_block_lgets++;
+ spin_unlock(&ino->i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+
+ WARN_ON(test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags));
+
+ lrp = kzalloc(sizeof(*lrp), GFP_KERNEL);
+ if (unlikely(lrp == NULL)) {
+ status = -ENOMEM;
+ set_bit(NFS_LAYOUT_RW_FAILED, &lo->plh_flags);
+ set_bit(NFS_LAYOUT_RO_FAILED, &lo->plh_flags);
+ put_layout_hdr(lo);
+ goto out;
+ }
+
+ lrp->args.stateid = stateid;
+ lrp->args.layout_type = NFS_SERVER(ino)->pnfs_curr_ld->id;
+ lrp->args.inode = ino;
+ lrp->args.layout = lo;
+ lrp->clp = NFS_SERVER(ino)->nfs_client;
+
+ status = nfs4_proc_layoutreturn(lrp);
+out:
+ dprintk("<-- %s status: %d\n", __func__, status);
+ return status;
+}
+
+bool pnfs_roc(struct inode *ino)
+{
+ struct pnfs_layout_hdr *lo;
+ struct pnfs_layout_segment *lseg, *tmp;
+ LIST_HEAD(tmp_list);
+ bool found = false;
+
+ spin_lock(&ino->i_lock);
+ lo = NFS_I(ino)->layout;
+ if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
+ test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
+ goto out_nolayout;
+ list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
+ if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
+ mark_lseg_invalid(lseg, &tmp_list);
+ found = true;
+ }
+ if (!found)
+ goto out_nolayout;
+ lo->plh_block_lgets++;
+ get_layout_hdr(lo); /* matched in pnfs_roc_release */
+ spin_unlock(&ino->i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+ return true;
+
+out_nolayout:
+ spin_unlock(&ino->i_lock);
+ return false;
+}
+
+void pnfs_roc_release(struct inode *ino)
+{
+ struct pnfs_layout_hdr *lo;
+
+ spin_lock(&ino->i_lock);
+ lo = NFS_I(ino)->layout;
+ lo->plh_block_lgets--;
+ put_layout_hdr_locked(lo);
+ spin_unlock(&ino->i_lock);
+}
+
+void pnfs_roc_set_barrier(struct inode *ino, u32 barrier)
+{
+ struct pnfs_layout_hdr *lo;
+
+ spin_lock(&ino->i_lock);
+ lo = NFS_I(ino)->layout;
+ if ((int)(barrier - lo->plh_barrier) > 0)
+ lo->plh_barrier = barrier;
+ spin_unlock(&ino->i_lock);
+}
+
+bool pnfs_roc_drain(struct inode *ino, u32 *barrier)
+{
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct pnfs_layout_segment *lseg;
+ bool found = false;
+
+ spin_lock(&ino->i_lock);
+ list_for_each_entry(lseg, &nfsi->layout->plh_segs, pls_list)
+ if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
+ found = true;
+ break;
+ }
+ if (!found) {
+ struct pnfs_layout_hdr *lo = nfsi->layout;
+ u32 current_seqid = be32_to_cpu(lo->plh_stateid.seqid);
+
+ /* Since close does not return a layout stateid for use as
+ * a barrier, we choose the worst-case barrier.
+ */
+ *barrier = current_seqid + atomic_read(&lo->plh_outstanding);
+ }
+ spin_unlock(&ino->i_lock);
+ return found;
+}
+
+/*
+ * Compare two layout segments for sorting into layout cache.
+ * We want to preferentially return RW over RO layouts, so ensure those
+ * are seen first.
+ */
+static s64
+cmp_layout(struct pnfs_layout_range *l1,
+ struct pnfs_layout_range *l2)
+{
+ s64 d;
+
+ /* high offset > low offset */
+ d = l1->offset - l2->offset;
+ if (d)
+ return d;
+
+ /* short length > long length */
+ d = l2->length - l1->length;
+ if (d)
+ return d;
+
+ /* read > read/write */
+ return (int)(l1->iomode == IOMODE_READ) - (int)(l2->iomode == IOMODE_READ);
+}
+
+static void
+pnfs_insert_layout(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_segment *lseg)
+{
+ struct pnfs_layout_segment *lp;
+
+ dprintk("%s:Begin\n", __func__);
+
+ assert_spin_locked(&lo->plh_inode->i_lock);
+ list_for_each_entry(lp, &lo->plh_segs, pls_list) {
+ if (cmp_layout(&lseg->pls_range, &lp->pls_range) > 0)
+ continue;
+ list_add_tail(&lseg->pls_list, &lp->pls_list);
+ dprintk("%s: inserted lseg %p "
+ "iomode %d offset %llu length %llu before "
+ "lp %p iomode %d offset %llu length %llu\n",
+ __func__, lseg, lseg->pls_range.iomode,
+ lseg->pls_range.offset, lseg->pls_range.length,
+ lp, lp->pls_range.iomode, lp->pls_range.offset,
+ lp->pls_range.length);
+ goto out;
+ }
+ list_add_tail(&lseg->pls_list, &lo->plh_segs);
+ dprintk("%s: inserted lseg %p "
+ "iomode %d offset %llu length %llu at tail\n",
+ __func__, lseg, lseg->pls_range.iomode,
+ lseg->pls_range.offset, lseg->pls_range.length);
+out:
+ get_layout_hdr(lo);
+
+ dprintk("%s:Return\n", __func__);
+}
+
+static struct pnfs_layout_hdr *
+alloc_init_layout_hdr(struct inode *ino,
+ struct nfs_open_context *ctx,
+ gfp_t gfp_flags)
+{
+ struct pnfs_layout_hdr *lo;
+
+ lo = pnfs_alloc_layout_hdr(ino, gfp_flags);
+ if (!lo)
+ return NULL;
+ atomic_set(&lo->plh_refcount, 1);
+ INIT_LIST_HEAD(&lo->plh_layouts);
+ INIT_LIST_HEAD(&lo->plh_segs);
+ INIT_LIST_HEAD(&lo->plh_bulk_recall);
+ lo->plh_inode = ino;
+ lo->plh_lc_cred = get_rpccred(ctx->state->owner->so_cred);
+ return lo;
+}
+
+static struct pnfs_layout_hdr *
+pnfs_find_alloc_layout(struct inode *ino,
+ struct nfs_open_context *ctx,
+ gfp_t gfp_flags)
+{
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct pnfs_layout_hdr *new = NULL;
+
+ dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
+
+ assert_spin_locked(&ino->i_lock);
+ if (nfsi->layout) {
+ if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
+ return NULL;
+ else
+ return nfsi->layout;
+ }
+ spin_unlock(&ino->i_lock);
+ new = alloc_init_layout_hdr(ino, ctx, gfp_flags);
+ spin_lock(&ino->i_lock);
+
+ if (likely(nfsi->layout == NULL)) /* Won the race? */
+ nfsi->layout = new;
+ else
+ pnfs_free_layout_hdr(new);
+ return nfsi->layout;
+}
+
+/*
+ * iomode matching rules:
+ * iomode lseg match
+ * ----- ----- -----
+ * ANY READ true
+ * ANY RW true
+ * RW READ false
+ * RW RW true
+ * READ READ true
+ * READ RW true
+ */
+static int
+is_matching_lseg(struct pnfs_layout_range *ls_range,
+ struct pnfs_layout_range *range)
+{
+ struct pnfs_layout_range range1;
+
+ if ((range->iomode == IOMODE_RW &&
+ ls_range->iomode != IOMODE_RW) ||
+ !lo_seg_intersecting(ls_range, range))
+ return 0;
+
+ /* range1 covers only the first byte in the range */
+ range1 = *range;
+ range1.length = 1;
+ return lo_seg_contained(ls_range, &range1);
+}
+
+/*
+ * lookup range in layout
+ */
+static struct pnfs_layout_segment *
+pnfs_find_lseg(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range)
+{
+ struct pnfs_layout_segment *lseg, *ret = NULL;
+
+ dprintk("%s:Begin\n", __func__);
+
+ assert_spin_locked(&lo->plh_inode->i_lock);
+ list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
+ if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
+ is_matching_lseg(&lseg->pls_range, range)) {
+ ret = get_lseg(lseg);
+ break;
+ }
+ if (lseg->pls_range.offset > range->offset)
+ break;
+ }
+
+ dprintk("%s:Return lseg %p ref %d\n",
+ __func__, ret, ret ? atomic_read(&ret->pls_refcount) : 0);
+ return ret;
+}
+
+/*
+ * Layout segment is retreived from the server if not cached.
+ * The appropriate layout segment is referenced and returned to the caller.
+ */
+struct pnfs_layout_segment *
+pnfs_update_layout(struct inode *ino,
+ struct nfs_open_context *ctx,
+ loff_t pos,
+ u64 count,
+ enum pnfs_iomode iomode,
+ gfp_t gfp_flags)
+{
+ struct pnfs_layout_range arg = {
+ .iomode = iomode,
+ .offset = pos,
+ .length = count,
+ };
+ unsigned pg_offset;
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct nfs_server *server = NFS_SERVER(ino);
+ struct nfs_client *clp = server->nfs_client;
+ struct pnfs_layout_hdr *lo;
+ struct pnfs_layout_segment *lseg = NULL;
+ bool first = false;
+
+ if (!pnfs_enabled_sb(NFS_SERVER(ino)))
+ return NULL;
+ spin_lock(&ino->i_lock);
+ lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
+ if (lo == NULL) {
+ dprintk("%s ERROR: can't get pnfs_layout_hdr\n", __func__);
+ goto out_unlock;
+ }
+
+ /* Do we even need to bother with this? */
+ if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
+ dprintk("%s matches recall, use MDS\n", __func__);
+ goto out_unlock;
+ }
+
+ /* if LAYOUTGET already failed once we don't try again */
+ if (test_bit(lo_fail_bit(iomode), &nfsi->layout->plh_flags))
+ goto out_unlock;
+
+ /* Check to see if the layout for the given range already exists */
+ lseg = pnfs_find_lseg(lo, &arg);
+ if (lseg)
+ goto out_unlock;
+
+ if (pnfs_layoutgets_blocked(lo, NULL, 0))
+ goto out_unlock;
+ atomic_inc(&lo->plh_outstanding);
+
+ get_layout_hdr(lo);
+ if (list_empty(&lo->plh_segs))
+ first = true;
+ spin_unlock(&ino->i_lock);
+ if (first) {
+ /* The lo must be on the clp list if there is any
+ * chance of a CB_LAYOUTRECALL(FILE) coming in.
+ */
+ spin_lock(&clp->cl_lock);
+ BUG_ON(!list_empty(&lo->plh_layouts));
+ list_add_tail(&lo->plh_layouts, &server->layouts);
+ spin_unlock(&clp->cl_lock);
+ }
+
+ pg_offset = arg.offset & ~PAGE_CACHE_MASK;
+ if (pg_offset) {
+ arg.offset -= pg_offset;
+ arg.length += pg_offset;
+ }
+ if (arg.length != NFS4_MAX_UINT64)
+ arg.length = PAGE_CACHE_ALIGN(arg.length);
+
+ lseg = send_layoutget(lo, ctx, &arg, gfp_flags);
+ if (!lseg && first) {
+ spin_lock(&clp->cl_lock);
+ list_del_init(&lo->plh_layouts);
+ spin_unlock(&clp->cl_lock);
+ }
+ atomic_dec(&lo->plh_outstanding);
+ put_layout_hdr(lo);
+out:
+ dprintk("%s end, state 0x%lx lseg %p\n", __func__,
+ nfsi->layout ? nfsi->layout->plh_flags : -1, lseg);
+ return lseg;
+out_unlock:
+ spin_unlock(&ino->i_lock);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(pnfs_update_layout);
+
+int
+pnfs_layout_process(struct nfs4_layoutget *lgp)
+{
+ struct pnfs_layout_hdr *lo = NFS_I(lgp->args.inode)->layout;
+ struct nfs4_layoutget_res *res = &lgp->res;
+ struct pnfs_layout_segment *lseg;
+ struct inode *ino = lo->plh_inode;
+ int status = 0;
+
+ /* Inject layout blob into I/O device driver */
+ lseg = NFS_SERVER(ino)->pnfs_curr_ld->alloc_lseg(lo, res, lgp->gfp_flags);
+ if (!lseg || IS_ERR(lseg)) {
+ if (!lseg)
+ status = -ENOMEM;
+ else
+ status = PTR_ERR(lseg);
+ dprintk("%s: Could not allocate layout: error %d\n",
+ __func__, status);
+ goto out;
+ }
+
+ spin_lock(&ino->i_lock);
+ if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
+ dprintk("%s forget reply due to recall\n", __func__);
+ goto out_forget_reply;
+ }
+
+ if (pnfs_layoutgets_blocked(lo, &res->stateid, 1)) {
+ dprintk("%s forget reply due to state\n", __func__);
+ goto out_forget_reply;
+ }
+ init_lseg(lo, lseg);
+ lseg->pls_range = res->range;
+ *lgp->lsegpp = get_lseg(lseg);
+ pnfs_insert_layout(lo, lseg);
+
+ if (res->return_on_close) {
+ set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
+ set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
+ }
+
+ /* Done processing layoutget. Set the layout stateid */
+ pnfs_set_layout_stateid(lo, &res->stateid, false);
+ spin_unlock(&ino->i_lock);
+out:
+ return status;
+
+out_forget_reply:
+ spin_unlock(&ino->i_lock);
+ lseg->pls_layout = lo;
+ NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
+ goto out;
+}
+
+void
+pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+ BUG_ON(pgio->pg_lseg != NULL);
+
+ pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+ req->wb_context,
+ req_offset(req),
+ req->wb_bytes,
+ IOMODE_READ,
+ GFP_KERNEL);
+ /* If no lseg, fall back to read through mds */
+ if (pgio->pg_lseg == NULL)
+ nfs_pageio_reset_read_mds(pgio);
+
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_read);
+
+void
+pnfs_generic_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+ BUG_ON(pgio->pg_lseg != NULL);
+
+ pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+ req->wb_context,
+ req_offset(req),
+ req->wb_bytes,
+ IOMODE_RW,
+ GFP_NOFS);
+ /* If no lseg, fall back to write through mds */
+ if (pgio->pg_lseg == NULL)
+ nfs_pageio_reset_write_mds(pgio);
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_init_write);
+
+bool
+pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *inode)
+{
+ 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);
+ return true;
+}
+
+bool
+pnfs_pageio_init_write(struct nfs_pageio_descriptor *pgio, struct inode *inode, int ioflags)
+{
+ 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);
+ return true;
+}
+
+bool
+pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+ struct nfs_page *req)
+{
+ if (pgio->pg_lseg == NULL)
+ return nfs_generic_pg_test(pgio, prev, req);
+
+ /*
+ * Test if a nfs_page is fully contained in the pnfs_layout_range.
+ * Note that this test makes several assumptions:
+ * - that the previous nfs_page in the struct nfs_pageio_descriptor
+ * is known to lie within the range.
+ * - that the nfs_page being tested is known to be contiguous with the
+ * previous nfs_page.
+ * - Layout ranges are page aligned, so we only have to test the
+ * start offset of the request.
+ *
+ * Please also note that 'end_offset' is actually the offset of the
+ * first byte that lies outside the pnfs_layout_range. FIXME?
+ *
+ */
+ return req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
+ pgio->pg_lseg->pls_range.length);
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
+
+static int pnfs_write_done_resend_to_mds(struct inode *inode, struct list_head *head)
+{
+ struct nfs_pageio_descriptor pgio;
+ LIST_HEAD(failed);
+
+ /* Resend all requests through the MDS */
+ nfs_pageio_init_write_mds(&pgio, inode, FLUSH_STABLE);
+ while (!list_empty(head)) {
+ struct nfs_page *req = nfs_list_entry(head->next);
+
+ nfs_list_remove_request(req);
+ if (!nfs_pageio_add_request(&pgio, req))
+ nfs_list_add_request(req, &failed);
+ }
+ nfs_pageio_complete(&pgio);
+
+ if (!list_empty(&failed)) {
+ /* For some reason our attempt to resend pages. Mark the
+ * overall send request as having failed, and let
+ * nfs_writeback_release_full deal with the error.
+ */
+ list_move(&failed, head);
+ return -EIO;
+ }
+ return 0;
+}
+
+/*
+ * Called by non rpc-based layout drivers
+ */
+void pnfs_ld_write_done(struct nfs_write_data *data)
+{
+ if (likely(!data->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);
+}
+EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
+
+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);
+ nfs_writedata_release(data);
+}
+
+static enum pnfs_try_status
+pnfs_try_to_write_data(struct nfs_write_data *wdata,
+ const struct rpc_call_ops *call_ops,
+ struct pnfs_layout_segment *lseg,
+ int how)
+{
+ struct inode *inode = wdata->inode;
+ enum pnfs_try_status trypnfs;
+ struct nfs_server *nfss = NFS_SERVER(inode);
+
+ wdata->mds_ops = call_ops;
+ wdata->lseg = get_lseg(lseg);
+
+ 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
+ nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
+
+ dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
+ return trypnfs;
+}
+
+static void
+pnfs_do_multiple_writes(struct nfs_pageio_descriptor *desc, struct list_head *head, int how)
+{
+ struct nfs_write_data *data;
+ const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
+ struct pnfs_layout_segment *lseg = desc->pg_lseg;
+
+ desc->pg_lseg = NULL;
+ while (!list_empty(head)) {
+ enum pnfs_try_status trypnfs;
+
+ data = list_entry(head->next, struct nfs_write_data, list);
+ list_del_init(&data->list);
+
+ trypnfs = pnfs_try_to_write_data(data, call_ops, lseg, how);
+ if (trypnfs == PNFS_NOT_ATTEMPTED)
+ pnfs_write_through_mds(desc, data);
+ }
+ put_lseg(lseg);
+}
+
+int
+pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
+{
+ LIST_HEAD(head);
+ int ret;
+
+ ret = nfs_generic_flush(desc, &head);
+ if (ret != 0) {
+ put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ return ret;
+ }
+ pnfs_do_multiple_writes(desc, &head, desc->pg_ioflags);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
+
+static void pnfs_ld_handle_read_error(struct nfs_read_data *data)
+{
+ struct nfs_pageio_descriptor pgio;
+
+ 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);
+
+ nfs_list_remove_request(req);
+ nfs_pageio_add_request(&pgio, req);
+ }
+ nfs_pageio_complete(&pgio);
+}
+
+/*
+ * Called by non rpc-based layout drivers
+ */
+void pnfs_ld_read_done(struct nfs_read_data *data)
+{
+ if (likely(!data->pnfs_error)) {
+ __nfs4_read_done_cb(data);
+ data->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);
+}
+EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
+
+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;
+ nfs_readdata_release(data);
+}
+
+/*
+ * Call the appropriate parallel I/O subsystem read function.
+ */
+static enum pnfs_try_status
+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_server *nfss = NFS_SERVER(inode);
+ enum pnfs_try_status trypnfs;
+
+ rdata->mds_ops = call_ops;
+ rdata->lseg = get_lseg(lseg);
+
+ 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 {
+ nfs_inc_stats(inode, NFSIOS_PNFS_READ);
+ }
+ dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
+ return trypnfs;
+}
+
+static void
+pnfs_do_multiple_reads(struct nfs_pageio_descriptor *desc, struct list_head *head)
+{
+ struct nfs_read_data *data;
+ const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
+ struct pnfs_layout_segment *lseg = desc->pg_lseg;
+
+ desc->pg_lseg = NULL;
+ while (!list_empty(head)) {
+ enum pnfs_try_status trypnfs;
+
+ data = list_entry(head->next, struct nfs_read_data, list);
+ list_del_init(&data->list);
+
+ trypnfs = pnfs_try_to_read_data(data, call_ops, lseg);
+ if (trypnfs == PNFS_NOT_ATTEMPTED)
+ pnfs_read_through_mds(desc, data);
+ }
+ put_lseg(lseg);
+}
+
+int
+pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
+{
+ LIST_HEAD(head);
+ int ret;
+
+ ret = nfs_generic_pagein(desc, &head);
+ if (ret != 0) {
+ put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ return ret;
+ }
+ pnfs_do_multiple_reads(desc, &head);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
+
+/*
+ * There can be multiple RW segments.
+ */
+static void pnfs_list_write_lseg(struct inode *inode, struct list_head *listp)
+{
+ struct pnfs_layout_segment *lseg;
+
+ list_for_each_entry(lseg, &NFS_I(inode)->layout->plh_segs, pls_list) {
+ if (lseg->pls_range.iomode == IOMODE_RW &&
+ test_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
+ list_add(&lseg->pls_lc_list, listp);
+ }
+}
+
+void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
+{
+ if (lseg->pls_range.iomode == IOMODE_RW) {
+ dprintk("%s Setting layout IOMODE_RW fail bit\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_RW), &lseg->pls_layout->plh_flags);
+ } else {
+ dprintk("%s Setting layout IOMODE_READ fail bit\n", __func__);
+ set_bit(lo_fail_bit(IOMODE_READ), &lseg->pls_layout->plh_flags);
+ }
+}
+EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
+
+void
+pnfs_set_layoutcommit(struct nfs_write_data *wdata)
+{
+ struct nfs_inode *nfsi = NFS_I(wdata->inode);
+ loff_t end_pos = wdata->mds_offset + wdata->res.count;
+ bool mark_as_dirty = false;
+
+ spin_lock(&nfsi->vfs_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);
+ }
+ if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &wdata->lseg->pls_flags)) {
+ /* references matched in nfs4_layoutcommit_release */
+ get_lseg(wdata->lseg);
+ }
+ if (end_pos > nfsi->layout->plh_lwb)
+ nfsi->layout->plh_lwb = end_pos;
+ spin_unlock(&nfsi->vfs_inode.i_lock);
+ dprintk("%s: lseg %p end_pos %llu\n",
+ __func__, wdata->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);
+}
+EXPORT_SYMBOL_GPL(pnfs_set_layoutcommit);
+
+void pnfs_cleanup_layoutcommit(struct nfs4_layoutcommit_data *data)
+{
+ struct nfs_server *nfss = NFS_SERVER(data->args.inode);
+
+ if (nfss->pnfs_curr_ld->cleanup_layoutcommit)
+ nfss->pnfs_curr_ld->cleanup_layoutcommit(data);
+}
+
+/*
+ * For the LAYOUT4_NFSV4_1_FILES layout type, NFS_DATA_SYNC WRITEs and
+ * NFS_UNSTABLE WRITEs with a COMMIT to data servers must store enough
+ * data to disk to allow the server to recover the data if it crashes.
+ * LAYOUTCOMMIT is only needed when the NFL4_UFLG_COMMIT_THRU_MDS flag
+ * is off, and a COMMIT is sent to a data server, or
+ * if WRITEs to a data server return NFS_DATA_SYNC.
+ */
+int
+pnfs_layoutcommit_inode(struct inode *inode, bool sync)
+{
+ struct nfs4_layoutcommit_data *data;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ loff_t end_pos;
+ int status = 0;
+
+ dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
+
+ if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
+ return 0;
+
+ /* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
+ data = kzalloc(sizeof(*data), GFP_NOFS);
+ if (!data) {
+ status = -ENOMEM;
+ goto out;
+ }
+
+ if (!test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
+ goto out_free;
+
+ if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
+ if (!sync) {
+ status = -EAGAIN;
+ goto out_free;
+ }
+ status = wait_on_bit_lock(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING,
+ nfs_wait_bit_killable, TASK_KILLABLE);
+ if (status)
+ goto out_free;
+ }
+
+ INIT_LIST_HEAD(&data->lseg_list);
+ spin_lock(&inode->i_lock);
+ if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
+ clear_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags);
+ spin_unlock(&inode->i_lock);
+ wake_up_bit(&nfsi->flags, NFS_INO_LAYOUTCOMMITTING);
+ goto out_free;
+ }
+
+ pnfs_list_write_lseg(inode, &data->lseg_list);
+
+ end_pos = nfsi->layout->plh_lwb;
+ nfsi->layout->plh_lwb = 0;
+
+ nfs4_stateid_copy(&data->args.stateid, &nfsi->layout->plh_stateid);
+ spin_unlock(&inode->i_lock);
+
+ data->args.inode = inode;
+ data->cred = get_rpccred(nfsi->layout->plh_lc_cred);
+ nfs_fattr_init(&data->fattr);
+ data->args.bitmask = NFS_SERVER(inode)->cache_consistency_bitmask;
+ data->res.fattr = &data->fattr;
+ data->args.lastbytewritten = end_pos - 1;
+ data->res.server = NFS_SERVER(inode);
+
+ status = nfs4_proc_layoutcommit(data, sync);
+out:
+ if (status)
+ mark_inode_dirty_sync(inode);
+ dprintk("<-- %s status %d\n", __func__, status);
+ return status;
+out_free:
+ kfree(data);
+ goto out;
+}