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-rw-r--r--fs/nfs/pnfs.c2252
1 files changed, 2252 insertions, 0 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
new file mode 100644
index 000000000..d47c18868
--- /dev/null
+++ b/fs/nfs/pnfs.c
@@ -0,0 +1,2252 @@
+/*
+ * 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"
+#include "nfs4trace.h"
+#include "delegation.h"
+
+#define NFSDBG_FACILITY NFSDBG_PNFS
+#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
+
+/* 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);
+
+static int
+pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, nfs4_stateid stateid,
+ enum pnfs_iomode iomode, bool sync);
+
+/* 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);
+ if (local != NULL && !try_module_get(local->owner)) {
+ dprintk("%s: Could not grab reference on module\n", __func__);
+ local = NULL;
+ }
+ 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);
+ /* Decrement the MDS count. Purge the deviceid cache if zero */
+ if (atomic_dec_and_test(&nfss->nfs_client->cl_mds_count))
+ nfs4_deviceid_purge_client(nfss->nfs_client);
+ 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;
+ }
+ }
+ 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;
+ }
+ /* Bump the MDS count */
+ atomic_inc(&server->nfs_client->cl_mds_count);
+
+ 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
+pnfs_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(ino, gfp_flags);
+}
+
+static void
+pnfs_free_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ struct nfs_server *server = NFS_SERVER(lo->plh_inode);
+ struct pnfs_layoutdriver_type *ld = server->pnfs_curr_ld;
+
+ if (!list_empty(&lo->plh_layouts)) {
+ struct nfs_client *clp = server->nfs_client;
+
+ spin_lock(&clp->cl_lock);
+ list_del_init(&lo->plh_layouts);
+ spin_unlock(&clp->cl_lock);
+ }
+ put_rpccred(lo->plh_lc_cred);
+ return ld->free_layout_hdr(lo);
+}
+
+static void
+pnfs_detach_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ struct nfs_inode *nfsi = NFS_I(lo->plh_inode);
+ dprintk("%s: freeing layout cache %p\n", __func__, lo);
+ nfsi->layout = NULL;
+ /* Reset MDS Threshold I/O counters */
+ nfsi->write_io = 0;
+ nfsi->read_io = 0;
+}
+
+void
+pnfs_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)) {
+ if (!list_empty(&lo->plh_segs))
+ WARN_ONCE(1, "NFS: BUG unfreed layout segments.\n");
+ pnfs_detach_layout_hdr(lo);
+ spin_unlock(&inode->i_lock);
+ pnfs_free_layout_hdr(lo);
+ }
+}
+
+static int
+pnfs_iomode_to_fail_bit(u32 iomode)
+{
+ return iomode == IOMODE_RW ?
+ NFS_LAYOUT_RW_FAILED : NFS_LAYOUT_RO_FAILED;
+}
+
+static void
+pnfs_layout_set_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
+{
+ lo->plh_retry_timestamp = jiffies;
+ if (!test_and_set_bit(fail_bit, &lo->plh_flags))
+ atomic_inc(&lo->plh_refcount);
+}
+
+static void
+pnfs_layout_clear_fail_bit(struct pnfs_layout_hdr *lo, int fail_bit)
+{
+ if (test_and_clear_bit(fail_bit, &lo->plh_flags))
+ atomic_dec(&lo->plh_refcount);
+}
+
+static void
+pnfs_layout_io_set_failed(struct pnfs_layout_hdr *lo, u32 iomode)
+{
+ struct inode *inode = lo->plh_inode;
+ struct pnfs_layout_range range = {
+ .iomode = iomode,
+ .offset = 0,
+ .length = NFS4_MAX_UINT64,
+ };
+ LIST_HEAD(head);
+
+ spin_lock(&inode->i_lock);
+ pnfs_layout_set_fail_bit(lo, pnfs_iomode_to_fail_bit(iomode));
+ pnfs_mark_matching_lsegs_invalid(lo, &head, &range);
+ spin_unlock(&inode->i_lock);
+ pnfs_free_lseg_list(&head);
+ dprintk("%s Setting layout IOMODE_%s fail bit\n", __func__,
+ iomode == IOMODE_RW ? "RW" : "READ");
+}
+
+static bool
+pnfs_layout_io_test_failed(struct pnfs_layout_hdr *lo, u32 iomode)
+{
+ unsigned long start, end;
+ int fail_bit = pnfs_iomode_to_fail_bit(iomode);
+
+ if (test_bit(fail_bit, &lo->plh_flags) == 0)
+ return false;
+ end = jiffies;
+ start = end - PNFS_LAYOUTGET_RETRY_TIMEOUT;
+ if (!time_in_range(lo->plh_retry_timestamp, start, end)) {
+ /* It is time to retry the failed layoutgets */
+ pnfs_layout_clear_fail_bit(lo, fail_bit);
+ return false;
+ }
+ return true;
+}
+
+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 pnfs_free_lseg(struct pnfs_layout_segment *lseg)
+{
+ struct inode *ino = lseg->pls_layout->plh_inode;
+
+ NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
+}
+
+static void
+pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_segment *lseg)
+{
+ struct inode *inode = lo->plh_inode;
+
+ WARN_ON(test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
+ list_del_init(&lseg->pls_list);
+ /* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
+ atomic_dec(&lo->plh_refcount);
+ if (list_empty(&lo->plh_segs))
+ clear_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
+ rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
+}
+
+/* Return true if layoutreturn is needed */
+static bool
+pnfs_layout_need_return(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_segment *lseg)
+{
+ struct pnfs_layout_segment *s;
+
+ if (!test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
+ return false;
+
+ list_for_each_entry(s, &lo->plh_segs, pls_list)
+ if (s != lseg && test_bit(NFS_LSEG_LAYOUTRETURN, &s->pls_flags))
+ return false;
+
+ return true;
+}
+
+static void pnfs_layoutreturn_before_put_lseg(struct pnfs_layout_segment *lseg,
+ struct pnfs_layout_hdr *lo, struct inode *inode)
+{
+ lo = lseg->pls_layout;
+ inode = lo->plh_inode;
+
+ spin_lock(&inode->i_lock);
+ if (pnfs_layout_need_return(lo, lseg)) {
+ nfs4_stateid stateid;
+ enum pnfs_iomode iomode;
+
+ stateid = lo->plh_stateid;
+ iomode = lo->plh_return_iomode;
+ /* decreased in pnfs_send_layoutreturn() */
+ lo->plh_block_lgets++;
+ lo->plh_return_iomode = 0;
+ spin_unlock(&inode->i_lock);
+ pnfs_get_layout_hdr(lo);
+
+ /* Send an async layoutreturn so we dont deadlock */
+ pnfs_send_layoutreturn(lo, stateid, iomode, false);
+ } else
+ spin_unlock(&inode->i_lock);
+}
+
+void
+pnfs_put_lseg(struct pnfs_layout_segment *lseg)
+{
+ struct pnfs_layout_hdr *lo;
+ 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));
+
+ /* Handle the case where refcount != 1 */
+ if (atomic_add_unless(&lseg->pls_refcount, -1, 1))
+ return;
+
+ lo = lseg->pls_layout;
+ inode = lo->plh_inode;
+ /* Do we need a layoutreturn? */
+ if (test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags))
+ pnfs_layoutreturn_before_put_lseg(lseg, lo, inode);
+
+ if (atomic_dec_and_lock(&lseg->pls_refcount, &inode->i_lock)) {
+ pnfs_get_layout_hdr(lo);
+ pnfs_layout_remove_lseg(lo, lseg);
+ spin_unlock(&inode->i_lock);
+ pnfs_free_lseg(lseg);
+ pnfs_put_layout_hdr(lo);
+ }
+}
+EXPORT_SYMBOL_GPL(pnfs_put_lseg);
+
+static void pnfs_free_lseg_async_work(struct work_struct *work)
+{
+ struct pnfs_layout_segment *lseg;
+ struct pnfs_layout_hdr *lo;
+
+ lseg = container_of(work, struct pnfs_layout_segment, pls_work);
+ lo = lseg->pls_layout;
+
+ pnfs_free_lseg(lseg);
+ pnfs_put_layout_hdr(lo);
+}
+
+static void pnfs_free_lseg_async(struct pnfs_layout_segment *lseg)
+{
+ INIT_WORK(&lseg->pls_work, pnfs_free_lseg_async_work);
+ schedule_work(&lseg->pls_work);
+}
+
+void
+pnfs_put_lseg_locked(struct pnfs_layout_segment *lseg)
+{
+ if (!lseg)
+ return;
+
+ assert_spin_locked(&lseg->pls_layout->plh_inode->i_lock);
+
+ dprintk("%s: lseg %p ref %d valid %d\n", __func__, lseg,
+ atomic_read(&lseg->pls_refcount),
+ test_bit(NFS_LSEG_VALID, &lseg->pls_flags));
+ if (atomic_dec_and_test(&lseg->pls_refcount)) {
+ struct pnfs_layout_hdr *lo = lseg->pls_layout;
+ pnfs_get_layout_hdr(lo);
+ pnfs_layout_remove_lseg(lo, lseg);
+ pnfs_free_lseg_async(lseg);
+ }
+}
+EXPORT_SYMBOL_GPL(pnfs_put_lseg_locked);
+
+static u64
+end_offset(u64 start, u64 len)
+{
+ u64 end;
+
+ end = start + len;
+ return end >= start ? end : NFS4_MAX_UINT64;
+}
+
+/*
+ * is l2 fully contained in l1?
+ * start1 end1
+ * [----------------------------------)
+ * start2 end2
+ * [----------------)
+ */
+static bool
+pnfs_lseg_range_contained(const struct pnfs_layout_range *l1,
+ const 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 bool
+pnfs_lseg_range_intersecting(const struct pnfs_layout_range *l1,
+ const 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(const struct pnfs_layout_range *lseg_range,
+ const struct pnfs_layout_range *recall_range)
+{
+ return (recall_range->iomode == IOMODE_ANY ||
+ lseg_range->iomode == recall_range->iomode) &&
+ pnfs_lseg_range_intersecting(lseg_range, recall_range);
+}
+
+static bool pnfs_lseg_dec_and_remove_zero(struct pnfs_layout_segment *lseg,
+ struct list_head *tmp_list)
+{
+ if (!atomic_dec_and_test(&lseg->pls_refcount))
+ return false;
+ pnfs_layout_remove_lseg(lseg->pls_layout, lseg);
+ list_add(&lseg->pls_list, tmp_list);
+ return true;
+}
+
+/* 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 (pnfs_lseg_dec_and_remove_zero(lseg, tmp_list))
+ rv = 1;
+ }
+ return rv;
+}
+
+/* Returns count of number of matching invalid lsegs remaining in list
+ * after call.
+ */
+int
+pnfs_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))
+ 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;
+
+ if (list_empty(free_me))
+ return;
+
+ list_for_each_entry_safe(lseg, tmp, free_me, pls_list) {
+ list_del(&lseg->pls_list);
+ pnfs_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 */
+ pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
+ pnfs_get_layout_hdr(lo);
+ pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RO_FAILED);
+ pnfs_layout_clear_fail_bit(lo, NFS_LAYOUT_RW_FAILED);
+ pnfs_clear_retry_layoutget(lo);
+ spin_unlock(&nfsi->vfs_inode.i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+ pnfs_put_layout_hdr(lo);
+ } else
+ spin_unlock(&nfsi->vfs_inode.i_lock);
+}
+EXPORT_SYMBOL_GPL(pnfs_destroy_layout);
+
+static bool
+pnfs_layout_add_bulk_destroy_list(struct inode *inode,
+ struct list_head *layout_list)
+{
+ struct pnfs_layout_hdr *lo;
+ bool ret = false;
+
+ spin_lock(&inode->i_lock);
+ lo = NFS_I(inode)->layout;
+ if (lo != NULL && list_empty(&lo->plh_bulk_destroy)) {
+ pnfs_get_layout_hdr(lo);
+ list_add(&lo->plh_bulk_destroy, layout_list);
+ ret = true;
+ }
+ spin_unlock(&inode->i_lock);
+ return ret;
+}
+
+/* Caller must hold rcu_read_lock and clp->cl_lock */
+static int
+pnfs_layout_bulk_destroy_byserver_locked(struct nfs_client *clp,
+ struct nfs_server *server,
+ struct list_head *layout_list)
+{
+ struct pnfs_layout_hdr *lo, *next;
+ struct inode *inode;
+
+ list_for_each_entry_safe(lo, next, &server->layouts, plh_layouts) {
+ inode = igrab(lo->plh_inode);
+ if (inode == NULL)
+ continue;
+ list_del_init(&lo->plh_layouts);
+ if (pnfs_layout_add_bulk_destroy_list(inode, layout_list))
+ continue;
+ rcu_read_unlock();
+ spin_unlock(&clp->cl_lock);
+ iput(inode);
+ spin_lock(&clp->cl_lock);
+ rcu_read_lock();
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static int
+pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
+ bool is_bulk_recall)
+{
+ struct pnfs_layout_hdr *lo;
+ struct inode *inode;
+ struct pnfs_layout_range range = {
+ .iomode = IOMODE_ANY,
+ .offset = 0,
+ .length = NFS4_MAX_UINT64,
+ };
+ LIST_HEAD(lseg_list);
+ int ret = 0;
+
+ while (!list_empty(layout_list)) {
+ lo = list_entry(layout_list->next, struct pnfs_layout_hdr,
+ plh_bulk_destroy);
+ dprintk("%s freeing layout for inode %lu\n", __func__,
+ lo->plh_inode->i_ino);
+ inode = lo->plh_inode;
+
+ pnfs_layoutcommit_inode(inode, false);
+
+ spin_lock(&inode->i_lock);
+ list_del_init(&lo->plh_bulk_destroy);
+ lo->plh_block_lgets++; /* permanently block new LAYOUTGETs */
+ if (is_bulk_recall)
+ set_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags);
+ if (pnfs_mark_matching_lsegs_invalid(lo, &lseg_list, &range))
+ ret = -EAGAIN;
+ spin_unlock(&inode->i_lock);
+ pnfs_free_lseg_list(&lseg_list);
+ pnfs_put_layout_hdr(lo);
+ iput(inode);
+ }
+ return ret;
+}
+
+int
+pnfs_destroy_layouts_byfsid(struct nfs_client *clp,
+ struct nfs_fsid *fsid,
+ bool is_recall)
+{
+ struct nfs_server *server;
+ LIST_HEAD(layout_list);
+
+ spin_lock(&clp->cl_lock);
+ rcu_read_lock();
+restart:
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ if (memcmp(&server->fsid, fsid, sizeof(*fsid)) != 0)
+ continue;
+ if (pnfs_layout_bulk_destroy_byserver_locked(clp,
+ server,
+ &layout_list) != 0)
+ goto restart;
+ }
+ rcu_read_unlock();
+ spin_unlock(&clp->cl_lock);
+
+ if (list_empty(&layout_list))
+ return 0;
+ return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
+}
+
+int
+pnfs_destroy_layouts_byclid(struct nfs_client *clp,
+ bool is_recall)
+{
+ struct nfs_server *server;
+ LIST_HEAD(layout_list);
+
+ spin_lock(&clp->cl_lock);
+ rcu_read_lock();
+restart:
+ list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+ if (pnfs_layout_bulk_destroy_byserver_locked(clp,
+ server,
+ &layout_list) != 0)
+ goto restart;
+ }
+ rcu_read_unlock();
+ spin_unlock(&clp->cl_lock);
+
+ if (list_empty(&layout_list))
+ return 0;
+ return pnfs_layout_free_bulk_destroy_list(&layout_list, is_recall);
+}
+
+/*
+ * Called by the state manger to remove all layouts established under an
+ * expired lease.
+ */
+void
+pnfs_destroy_all_layouts(struct nfs_client *clp)
+{
+ nfs4_deviceid_mark_client_invalid(clp);
+ nfs4_deviceid_purge_client(clp);
+
+ pnfs_destroy_layouts_byclid(clp, false);
+}
+
+/*
+ * Compare 2 layout stateid sequence ids, to see which is newer,
+ * taking into account wraparound issues.
+ */
+static bool pnfs_seqid_is_newer(u32 s1, u32 s2)
+{
+ return (s32)(s1 - s2) > 0;
+}
+
+/* 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, new_barrier;
+ int empty = list_empty(&lo->plh_segs);
+
+ oldseq = be32_to_cpu(lo->plh_stateid.seqid);
+ newseq = be32_to_cpu(new->seqid);
+ if (empty || pnfs_seqid_is_newer(newseq, oldseq)) {
+ nfs4_stateid_copy(&lo->plh_stateid, new);
+ if (update_barrier) {
+ new_barrier = be32_to_cpu(new->seqid);
+ } else {
+ /* Because of wraparound, we want to keep the barrier
+ * "close" to the current seqids.
+ */
+ new_barrier = newseq - atomic_read(&lo->plh_outstanding);
+ }
+ if (empty || pnfs_seqid_is_newer(new_barrier, lo->plh_barrier))
+ lo->plh_barrier = new_barrier;
+ }
+}
+
+static bool
+pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
+ const nfs4_stateid *stateid)
+{
+ u32 seqid = be32_to_cpu(stateid->seqid);
+
+ return !pnfs_seqid_is_newer(seqid, lo->plh_barrier);
+}
+
+static bool
+pnfs_layout_returning(const struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range)
+{
+ return test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags) &&
+ (lo->plh_return_iomode == IOMODE_ANY ||
+ lo->plh_return_iomode == range->iomode);
+}
+
+/* lget is set to 1 if called from inside send_layoutget call chain */
+static bool
+pnfs_layoutgets_blocked(const struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range, int lget)
+{
+ return lo->plh_block_lgets ||
+ test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
+ (list_empty(&lo->plh_segs) &&
+ (atomic_read(&lo->plh_outstanding) > lget)) ||
+ pnfs_layout_returning(lo, range);
+}
+
+int
+pnfs_choose_layoutget_stateid(nfs4_stateid *dst, struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range,
+ struct nfs4_state *open_state)
+{
+ int status = 0;
+
+ dprintk("--> %s\n", __func__);
+ spin_lock(&lo->plh_inode->i_lock);
+ if (pnfs_layoutgets_blocked(lo, range, 1)) {
+ status = -EAGAIN;
+ } else if (!nfs4_valid_open_stateid(open_state)) {
+ status = -EBADF;
+ } else if (list_empty(&lo->plh_segs) ||
+ test_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags)) {
+ 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;
+
+ dprintk("--> %s\n", __func__);
+
+ lgp = kzalloc(sizeof(*lgp), gfp_flags);
+ if (lgp == NULL)
+ return NULL;
+
+ 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->gfp_flags = gfp_flags;
+ lgp->cred = lo->plh_lc_cred;
+
+ /* Synchronously retrieve layout information from server and
+ * store in lseg.
+ */
+ lseg = nfs4_proc_layoutget(lgp, gfp_flags);
+ if (IS_ERR(lseg)) {
+ switch (PTR_ERR(lseg)) {
+ case -ENOMEM:
+ case -ERESTARTSYS:
+ break;
+ default:
+ /* remember that LAYOUTGET failed and suspend trying */
+ pnfs_layout_io_set_failed(lo, range->iomode);
+ }
+ return NULL;
+ } else
+ pnfs_layout_clear_fail_bit(lo,
+ pnfs_iomode_to_fail_bit(range->iomode));
+
+ return lseg;
+}
+
+static void pnfs_clear_layoutcommit(struct inode *inode,
+ struct list_head *head)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ struct pnfs_layout_segment *lseg, *tmp;
+
+ if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
+ return;
+ list_for_each_entry_safe(lseg, tmp, &nfsi->layout->plh_segs, pls_list) {
+ if (!test_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
+ continue;
+ pnfs_lseg_dec_and_remove_zero(lseg, head);
+ }
+}
+
+void pnfs_clear_layoutreturn_waitbit(struct pnfs_layout_hdr *lo)
+{
+ clear_bit_unlock(NFS_LAYOUT_RETURN, &lo->plh_flags);
+ smp_mb__after_atomic();
+ wake_up_bit(&lo->plh_flags, NFS_LAYOUT_RETURN);
+}
+
+static int
+pnfs_send_layoutreturn(struct pnfs_layout_hdr *lo, nfs4_stateid stateid,
+ enum pnfs_iomode iomode, bool sync)
+{
+ struct inode *ino = lo->plh_inode;
+ struct nfs4_layoutreturn *lrp;
+ int status = 0;
+
+ lrp = kzalloc(sizeof(*lrp), GFP_NOFS);
+ if (unlikely(lrp == NULL)) {
+ status = -ENOMEM;
+ spin_lock(&ino->i_lock);
+ lo->plh_block_lgets--;
+ pnfs_clear_layoutreturn_waitbit(lo);
+ rpc_wake_up(&NFS_SERVER(ino)->roc_rpcwaitq);
+ spin_unlock(&ino->i_lock);
+ pnfs_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.range.iomode = iomode;
+ lrp->args.range.offset = 0;
+ lrp->args.range.length = NFS4_MAX_UINT64;
+ lrp->args.layout = lo;
+ lrp->clp = NFS_SERVER(ino)->nfs_client;
+ lrp->cred = lo->plh_lc_cred;
+
+ status = nfs4_proc_layoutreturn(lrp, sync);
+out:
+ dprintk("<-- %s status: %d\n", __func__, status);
+ return status;
+}
+
+/*
+ * Initiates a LAYOUTRETURN(FILE), and removes the pnfs_layout_hdr
+ * when the layout segment list is empty.
+ *
+ * Note that a pnfs_layout_hdr can exist with an empty layout segment
+ * list when LAYOUTGET has failed, or when LAYOUTGET succeeded, but the
+ * deviceid is marked invalid.
+ */
+int
+_pnfs_return_layout(struct inode *ino)
+{
+ struct pnfs_layout_hdr *lo = NULL;
+ struct nfs_inode *nfsi = NFS_I(ino);
+ LIST_HEAD(tmp_list);
+ nfs4_stateid stateid;
+ int status = 0, empty;
+
+ dprintk("NFS: %s for inode %lu\n", __func__, ino->i_ino);
+
+ spin_lock(&ino->i_lock);
+ lo = nfsi->layout;
+ if (!lo) {
+ spin_unlock(&ino->i_lock);
+ dprintk("NFS: %s no layout to return\n", __func__);
+ goto out;
+ }
+ stateid = nfsi->layout->plh_stateid;
+ /* Reference matched in nfs4_layoutreturn_release */
+ pnfs_get_layout_hdr(lo);
+ empty = list_empty(&lo->plh_segs);
+ pnfs_clear_layoutcommit(ino, &tmp_list);
+ pnfs_mark_matching_lsegs_invalid(lo, &tmp_list, NULL);
+
+ if (NFS_SERVER(ino)->pnfs_curr_ld->return_range) {
+ struct pnfs_layout_range range = {
+ .iomode = IOMODE_ANY,
+ .offset = 0,
+ .length = NFS4_MAX_UINT64,
+ };
+ NFS_SERVER(ino)->pnfs_curr_ld->return_range(lo, &range);
+ }
+
+ /* Don't send a LAYOUTRETURN if list was initially empty */
+ if (empty) {
+ spin_unlock(&ino->i_lock);
+ pnfs_put_layout_hdr(lo);
+ dprintk("NFS: %s no layout segments to return\n", __func__);
+ goto out;
+ }
+
+ set_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
+ lo->plh_block_lgets++;
+ spin_unlock(&ino->i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+
+ status = pnfs_send_layoutreturn(lo, stateid, IOMODE_ANY, true);
+out:
+ dprintk("<-- %s status: %d\n", __func__, status);
+ return status;
+}
+EXPORT_SYMBOL_GPL(_pnfs_return_layout);
+
+int
+pnfs_commit_and_return_layout(struct inode *inode)
+{
+ struct pnfs_layout_hdr *lo;
+ int ret;
+
+ spin_lock(&inode->i_lock);
+ lo = NFS_I(inode)->layout;
+ if (lo == NULL) {
+ spin_unlock(&inode->i_lock);
+ return 0;
+ }
+ pnfs_get_layout_hdr(lo);
+ /* Block new layoutgets and read/write to ds */
+ lo->plh_block_lgets++;
+ spin_unlock(&inode->i_lock);
+ filemap_fdatawait(inode->i_mapping);
+ ret = pnfs_layoutcommit_inode(inode, true);
+ if (ret == 0)
+ ret = _pnfs_return_layout(inode);
+ spin_lock(&inode->i_lock);
+ lo->plh_block_lgets--;
+ spin_unlock(&inode->i_lock);
+ pnfs_put_layout_hdr(lo);
+ return ret;
+}
+
+bool pnfs_roc(struct inode *ino)
+{
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct nfs_open_context *ctx;
+ struct nfs4_state *state;
+ struct pnfs_layout_hdr *lo;
+ struct pnfs_layout_segment *lseg, *tmp;
+ nfs4_stateid stateid;
+ LIST_HEAD(tmp_list);
+ bool found = false, layoutreturn = false;
+
+ spin_lock(&ino->i_lock);
+ lo = nfsi->layout;
+ if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
+ test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
+ goto out_noroc;
+
+ /* Don't return layout if we hold a delegation */
+ if (nfs4_check_delegation(ino, FMODE_READ))
+ goto out_noroc;
+
+ list_for_each_entry(ctx, &nfsi->open_files, list) {
+ state = ctx->state;
+ /* Don't return layout if there is open file state */
+ if (state != NULL && state->state != 0)
+ goto out_noroc;
+ }
+
+ pnfs_clear_retry_layoutget(lo);
+ 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_noroc;
+ lo->plh_block_lgets++;
+ pnfs_get_layout_hdr(lo); /* matched in pnfs_roc_release */
+ spin_unlock(&ino->i_lock);
+ pnfs_free_lseg_list(&tmp_list);
+ pnfs_layoutcommit_inode(ino, true);
+ return true;
+
+out_noroc:
+ if (lo) {
+ stateid = lo->plh_stateid;
+ layoutreturn =
+ test_and_clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
+ &lo->plh_flags);
+ if (layoutreturn) {
+ lo->plh_block_lgets++;
+ pnfs_get_layout_hdr(lo);
+ }
+ }
+ spin_unlock(&ino->i_lock);
+ if (layoutreturn) {
+ pnfs_layoutcommit_inode(ino, true);
+ pnfs_send_layoutreturn(lo, stateid, IOMODE_ANY, true);
+ }
+ 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--;
+ if (atomic_dec_and_test(&lo->plh_refcount)) {
+ pnfs_detach_layout_hdr(lo);
+ spin_unlock(&ino->i_lock);
+ pnfs_free_layout_hdr(lo);
+ } else
+ 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 (pnfs_seqid_is_newer(barrier, lo->plh_barrier))
+ lo->plh_barrier = barrier;
+ spin_unlock(&ino->i_lock);
+}
+
+bool pnfs_roc_drain(struct inode *ino, u32 *barrier, struct rpc_task *task)
+{
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct pnfs_layout_hdr *lo;
+ struct pnfs_layout_segment *lseg;
+ nfs4_stateid stateid;
+ u32 current_seqid;
+ bool found = false, layoutreturn = 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)) {
+ rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
+ found = true;
+ goto out;
+ }
+ lo = nfsi->layout;
+ 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);
+out:
+ if (!found) {
+ stateid = lo->plh_stateid;
+ layoutreturn =
+ test_and_clear_bit(NFS_LAYOUT_RETURN_BEFORE_CLOSE,
+ &lo->plh_flags);
+ if (layoutreturn) {
+ lo->plh_block_lgets++;
+ pnfs_get_layout_hdr(lo);
+ }
+ }
+ spin_unlock(&ino->i_lock);
+ if (layoutreturn) {
+ rpc_sleep_on(&NFS_SERVER(ino)->roc_rpcwaitq, task, NULL);
+ pnfs_send_layoutreturn(lo, stateid, IOMODE_ANY, false);
+ }
+ 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
+pnfs_lseg_range_cmp(const struct pnfs_layout_range *l1,
+ const 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_layout_insert_lseg(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_segment *lseg)
+{
+ struct pnfs_layout_segment *lp;
+
+ dprintk("%s:Begin\n", __func__);
+
+ list_for_each_entry(lp, &lo->plh_segs, pls_list) {
+ if (pnfs_lseg_range_cmp(&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:
+ pnfs_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_destroy);
+ lo->plh_inode = ino;
+ lo->plh_lc_cred = get_rpccred(ctx->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);
+
+ if (nfsi->layout != NULL)
+ goto out_existing;
+ 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;
+ return new;
+ } else if (new != NULL)
+ pnfs_free_layout_hdr(new);
+out_existing:
+ pnfs_get_layout_hdr(nfsi->layout);
+ 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 bool
+pnfs_lseg_range_match(const struct pnfs_layout_range *ls_range,
+ const struct pnfs_layout_range *range)
+{
+ struct pnfs_layout_range range1;
+
+ if ((range->iomode == IOMODE_RW &&
+ ls_range->iomode != IOMODE_RW) ||
+ !pnfs_lseg_range_intersecting(ls_range, range))
+ return 0;
+
+ /* range1 covers only the first byte in the range */
+ range1 = *range;
+ range1.length = 1;
+ return pnfs_lseg_range_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__);
+
+ list_for_each_entry(lseg, &lo->plh_segs, pls_list) {
+ if (test_bit(NFS_LSEG_VALID, &lseg->pls_flags) &&
+ !test_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags) &&
+ pnfs_lseg_range_match(&lseg->pls_range, range)) {
+ ret = pnfs_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;
+}
+
+/*
+ * 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;
+}
+
+/* stop waiting if someone clears NFS_LAYOUT_RETRY_LAYOUTGET bit. */
+static int pnfs_layoutget_retry_bit_wait(struct wait_bit_key *key)
+{
+ if (!test_bit(NFS_LAYOUT_RETRY_LAYOUTGET, key->flags))
+ return 1;
+ return nfs_wait_bit_killable(key);
+}
+
+static bool pnfs_prepare_to_retry_layoutget(struct pnfs_layout_hdr *lo)
+{
+ /*
+ * send layoutcommit as it can hold up layoutreturn due to lseg
+ * reference
+ */
+ pnfs_layoutcommit_inode(lo->plh_inode, false);
+ return !wait_on_bit_action(&lo->plh_flags, NFS_LAYOUT_RETURN,
+ pnfs_layoutget_retry_bit_wait,
+ TASK_UNINTERRUPTIBLE);
+}
+
+static void pnfs_clear_first_layoutget(struct pnfs_layout_hdr *lo)
+{
+ unsigned long *bitlock = &lo->plh_flags;
+
+ clear_bit_unlock(NFS_LAYOUT_FIRST_LAYOUTGET, bitlock);
+ smp_mb__after_atomic();
+ wake_up_bit(bitlock, NFS_LAYOUT_FIRST_LAYOUTGET);
+}
+
+/*
+ * 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_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;
+
+ if (!pnfs_enabled_sb(NFS_SERVER(ino)))
+ goto out;
+
+ if (pnfs_within_mdsthreshold(ctx, ino, iomode))
+ goto out;
+
+lookup_again:
+ first = false;
+ spin_lock(&ino->i_lock);
+ lo = pnfs_find_alloc_layout(ino, ctx, gfp_flags);
+ if (lo == NULL) {
+ spin_unlock(&ino->i_lock);
+ goto out;
+ }
+
+ /* 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 (pnfs_layout_io_test_failed(lo, iomode) &&
+ !pnfs_should_retry_layoutget(lo))
+ goto out_unlock;
+
+ first = list_empty(&lo->plh_segs);
+ if (first) {
+ /* The first layoutget for the file. Need to serialize per
+ * RFC 5661 Errata 3208.
+ */
+ if (test_and_set_bit(NFS_LAYOUT_FIRST_LAYOUTGET,
+ &lo->plh_flags)) {
+ spin_unlock(&ino->i_lock);
+ wait_on_bit(&lo->plh_flags, NFS_LAYOUT_FIRST_LAYOUTGET,
+ TASK_UNINTERRUPTIBLE);
+ pnfs_put_layout_hdr(lo);
+ goto lookup_again;
+ }
+ } else {
+ /* Check to see if the layout for the given range
+ * already exists
+ */
+ lseg = pnfs_find_lseg(lo, &arg);
+ if (lseg)
+ goto out_unlock;
+ }
+
+ /*
+ * Because we free lsegs before sending LAYOUTRETURN, we need to wait
+ * for LAYOUTRETURN even if first is true.
+ */
+ if (!lseg && pnfs_should_retry_layoutget(lo) &&
+ test_bit(NFS_LAYOUT_RETURN, &lo->plh_flags)) {
+ spin_unlock(&ino->i_lock);
+ dprintk("%s wait for layoutreturn\n", __func__);
+ if (pnfs_prepare_to_retry_layoutget(lo)) {
+ if (first)
+ pnfs_clear_first_layoutget(lo);
+ pnfs_put_layout_hdr(lo);
+ dprintk("%s retrying\n", __func__);
+ goto lookup_again;
+ }
+ goto out_put_layout_hdr;
+ }
+
+ if (pnfs_layoutgets_blocked(lo, &arg, 0))
+ goto out_unlock;
+ atomic_inc(&lo->plh_outstanding);
+ spin_unlock(&ino->i_lock);
+
+ if (list_empty(&lo->plh_layouts)) {
+ /* 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);
+ if (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);
+ pnfs_clear_retry_layoutget(lo);
+ atomic_dec(&lo->plh_outstanding);
+out_put_layout_hdr:
+ if (first)
+ pnfs_clear_first_layoutget(lo);
+ pnfs_put_layout_hdr(lo);
+out:
+ dprintk("%s: inode %s/%llu pNFS layout segment %s for "
+ "(%s, offset: %llu, length: %llu)\n",
+ __func__, ino->i_sb->s_id,
+ (unsigned long long)NFS_FILEID(ino),
+ lseg == NULL ? "not found" : "found",
+ iomode==IOMODE_RW ? "read/write" : "read-only",
+ (unsigned long long)pos,
+ (unsigned long long)count);
+ return lseg;
+out_unlock:
+ spin_unlock(&ino->i_lock);
+ goto out_put_layout_hdr;
+}
+EXPORT_SYMBOL_GPL(pnfs_update_layout);
+
+struct pnfs_layout_segment *
+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;
+ LIST_HEAD(free_me);
+ 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;
+ }
+
+ init_lseg(lo, lseg);
+ lseg->pls_range = res->range;
+
+ 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, &lgp->args.range, 1)) {
+ dprintk("%s forget reply due to state\n", __func__);
+ goto out_forget_reply;
+ }
+
+ if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
+ /* existing state ID, make sure the sequence number matches. */
+ if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
+ dprintk("%s forget reply due to sequence\n", __func__);
+ goto out_forget_reply;
+ }
+ pnfs_set_layout_stateid(lo, &res->stateid, false);
+ } else {
+ /*
+ * We got an entirely new state ID. Mark all segments for the
+ * inode invalid, and don't bother validating the stateid
+ * sequence number.
+ */
+ pnfs_mark_matching_lsegs_invalid(lo, &free_me, NULL);
+
+ nfs4_stateid_copy(&lo->plh_stateid, &res->stateid);
+ lo->plh_barrier = be32_to_cpu(res->stateid.seqid);
+ }
+
+ clear_bit(NFS_LAYOUT_INVALID_STID, &lo->plh_flags);
+
+ pnfs_get_lseg(lseg);
+ pnfs_layout_insert_lseg(lo, lseg);
+
+ if (res->return_on_close) {
+ set_bit(NFS_LSEG_ROC, &lseg->pls_flags);
+ set_bit(NFS_LAYOUT_ROC, &lo->plh_flags);
+ }
+
+ spin_unlock(&ino->i_lock);
+ pnfs_free_lseg_list(&free_me);
+ return lseg;
+out:
+ return ERR_PTR(status);
+
+out_forget_reply:
+ spin_unlock(&ino->i_lock);
+ lseg->pls_layout = lo;
+ NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
+ goto out;
+}
+
+static void
+pnfs_mark_matching_lsegs_return(struct pnfs_layout_hdr *lo,
+ struct list_head *tmp_list,
+ struct pnfs_layout_range *return_range)
+{
+ struct pnfs_layout_segment *lseg, *next;
+
+ dprintk("%s:Begin lo %p\n", __func__, lo);
+
+ if (list_empty(&lo->plh_segs))
+ return;
+
+ list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
+ if (should_free_lseg(&lseg->pls_range, return_range)) {
+ dprintk("%s: marking lseg %p iomode %d "
+ "offset %llu length %llu\n", __func__,
+ lseg, lseg->pls_range.iomode,
+ lseg->pls_range.offset,
+ lseg->pls_range.length);
+ set_bit(NFS_LSEG_LAYOUTRETURN, &lseg->pls_flags);
+ mark_lseg_invalid(lseg, tmp_list);
+ }
+}
+
+void pnfs_error_mark_layout_for_return(struct inode *inode,
+ struct pnfs_layout_segment *lseg)
+{
+ struct pnfs_layout_hdr *lo = NFS_I(inode)->layout;
+ int iomode = pnfs_iomode_to_fail_bit(lseg->pls_range.iomode);
+ struct pnfs_layout_range range = {
+ .iomode = lseg->pls_range.iomode,
+ .offset = 0,
+ .length = NFS4_MAX_UINT64,
+ };
+ LIST_HEAD(free_me);
+
+ spin_lock(&inode->i_lock);
+ /* set failure bit so that pnfs path will be retried later */
+ pnfs_layout_set_fail_bit(lo, iomode);
+ set_bit(NFS_LAYOUT_RETURN, &lo->plh_flags);
+ if (lo->plh_return_iomode == 0)
+ lo->plh_return_iomode = range.iomode;
+ else if (lo->plh_return_iomode != range.iomode)
+ lo->plh_return_iomode = IOMODE_ANY;
+ /*
+ * mark all matching lsegs so that we are sure to have no live
+ * segments at hand when sending layoutreturn. See pnfs_put_lseg()
+ * for how it works.
+ */
+ pnfs_mark_matching_lsegs_return(lo, &free_me, &range);
+ spin_unlock(&inode->i_lock);
+ pnfs_free_lseg_list(&free_me);
+}
+EXPORT_SYMBOL_GPL(pnfs_error_mark_layout_for_return);
+
+void
+pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+ u64 rd_size = req->wb_bytes;
+
+ if (pgio->pg_lseg == NULL) {
+ if (pgio->pg_dreq == NULL)
+ rd_size = i_size_read(pgio->pg_inode) - req_offset(req);
+ else
+ rd_size = nfs_dreq_bytes_left(pgio->pg_dreq);
+
+ pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+ req->wb_context,
+ req_offset(req),
+ rd_size,
+ 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, u64 wb_size)
+{
+ if (pgio->pg_lseg == NULL)
+ pgio->pg_lseg = pnfs_update_layout(pgio->pg_inode,
+ req->wb_context,
+ req_offset(req),
+ wb_size,
+ 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);
+
+void
+pnfs_generic_pg_cleanup(struct nfs_pageio_descriptor *desc)
+{
+ if (desc->pg_lseg) {
+ pnfs_put_lseg(desc->pg_lseg);
+ desc->pg_lseg = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_cleanup);
+
+/*
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+size_t
+pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio,
+ struct nfs_page *prev, struct nfs_page *req)
+{
+ unsigned int size;
+ u64 seg_end, req_start, seg_left;
+
+ size = nfs_generic_pg_test(pgio, prev, req);
+ if (!size)
+ return 0;
+
+ /*
+ * 'size' contains the number of bytes left in the current page (up
+ * to the original size asked for in @req->wb_bytes).
+ *
+ * Calculate how many bytes are left in the layout segment
+ * and if there are less bytes than 'size', return that instead.
+ *
+ * Please also note that 'end_offset' is actually the offset of the
+ * first byte that lies outside the pnfs_layout_range. FIXME?
+ *
+ */
+ if (pgio->pg_lseg) {
+ seg_end = end_offset(pgio->pg_lseg->pls_range.offset,
+ pgio->pg_lseg->pls_range.length);
+ req_start = req_offset(req);
+ WARN_ON_ONCE(req_start >= seg_end);
+ /* start of request is past the last byte of this segment */
+ if (req_start >= seg_end) {
+ /* reference the new lseg */
+ if (pgio->pg_ops->pg_cleanup)
+ pgio->pg_ops->pg_cleanup(pgio);
+ if (pgio->pg_ops->pg_init)
+ pgio->pg_ops->pg_init(pgio, req);
+ return 0;
+ }
+
+ /* adjust 'size' iff there are fewer bytes left in the
+ * segment than what nfs_generic_pg_test returned */
+ seg_left = seg_end - req_start;
+ if (seg_left < size)
+ size = (unsigned int)seg_left;
+ }
+
+ return size;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
+
+int pnfs_write_done_resend_to_mds(struct nfs_pgio_header *hdr)
+{
+ struct nfs_pageio_descriptor pgio;
+
+ /* Resend all requests through the MDS */
+ nfs_pageio_init_write(&pgio, hdr->inode, FLUSH_STABLE, true,
+ hdr->completion_ops);
+ set_bit(NFS_CONTEXT_RESEND_WRITES, &hdr->args.context->flags);
+ return nfs_pageio_resend(&pgio, hdr);
+}
+EXPORT_SYMBOL_GPL(pnfs_write_done_resend_to_mds);
+
+static void pnfs_ld_handle_write_error(struct nfs_pgio_header *hdr)
+{
+
+ dprintk("pnfs write error = %d\n", hdr->pnfs_error);
+ if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
+ PNFS_LAYOUTRET_ON_ERROR) {
+ pnfs_return_layout(hdr->inode);
+ }
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
+ hdr->task.tk_status = pnfs_write_done_resend_to_mds(hdr);
+}
+
+/*
+ * Called by non rpc-based layout drivers
+ */
+void pnfs_ld_write_done(struct nfs_pgio_header *hdr)
+{
+ trace_nfs4_pnfs_write(hdr, hdr->pnfs_error);
+ if (!hdr->pnfs_error) {
+ pnfs_set_layoutcommit(hdr->inode, hdr->lseg,
+ hdr->mds_offset + hdr->res.count);
+ hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
+ } else
+ pnfs_ld_handle_write_error(hdr);
+ hdr->mds_ops->rpc_release(hdr);
+}
+EXPORT_SYMBOL_GPL(pnfs_ld_write_done);
+
+static void
+pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
+ struct nfs_pgio_header *hdr)
+{
+ struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
+
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+ list_splice_tail_init(&hdr->pages, &mirror->pg_list);
+ nfs_pageio_reset_write_mds(desc);
+ mirror->pg_recoalesce = 1;
+ }
+ nfs_pgio_data_destroy(hdr);
+ hdr->release(hdr);
+}
+
+static enum pnfs_try_status
+pnfs_try_to_write_data(struct nfs_pgio_header *hdr,
+ const struct rpc_call_ops *call_ops,
+ struct pnfs_layout_segment *lseg,
+ int how)
+{
+ struct inode *inode = hdr->inode;
+ enum pnfs_try_status trypnfs;
+ struct nfs_server *nfss = NFS_SERVER(inode);
+
+ hdr->mds_ops = call_ops;
+
+ dprintk("%s: Writing ino:%lu %u@%llu (how %d)\n", __func__,
+ inode->i_ino, hdr->args.count, hdr->args.offset, how);
+ trypnfs = nfss->pnfs_curr_ld->write_pagelist(hdr, how);
+ if (trypnfs != PNFS_NOT_ATTEMPTED)
+ nfs_inc_stats(inode, NFSIOS_PNFS_WRITE);
+ dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
+ return trypnfs;
+}
+
+static void
+pnfs_do_write(struct nfs_pageio_descriptor *desc,
+ struct nfs_pgio_header *hdr, int how)
+{
+ const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
+ struct pnfs_layout_segment *lseg = desc->pg_lseg;
+ enum pnfs_try_status trypnfs;
+
+ trypnfs = pnfs_try_to_write_data(hdr, call_ops, lseg, how);
+ if (trypnfs == PNFS_NOT_ATTEMPTED)
+ pnfs_write_through_mds(desc, hdr);
+}
+
+static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
+{
+ pnfs_put_lseg(hdr->lseg);
+ nfs_pgio_header_free(hdr);
+}
+
+int
+pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
+{
+ struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
+
+ struct nfs_pgio_header *hdr;
+ int ret;
+
+ hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
+ if (!hdr) {
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
+ return -ENOMEM;
+ }
+ nfs_pgheader_init(desc, hdr, pnfs_writehdr_free);
+
+ hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
+ ret = nfs_generic_pgio(desc, hdr);
+ if (!ret)
+ pnfs_do_write(desc, hdr, desc->pg_ioflags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_writepages);
+
+int pnfs_read_done_resend_to_mds(struct nfs_pgio_header *hdr)
+{
+ struct nfs_pageio_descriptor pgio;
+
+ /* Resend all requests through the MDS */
+ nfs_pageio_init_read(&pgio, hdr->inode, true, hdr->completion_ops);
+ return nfs_pageio_resend(&pgio, hdr);
+}
+EXPORT_SYMBOL_GPL(pnfs_read_done_resend_to_mds);
+
+static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
+{
+ dprintk("pnfs read error = %d\n", hdr->pnfs_error);
+ if (NFS_SERVER(hdr->inode)->pnfs_curr_ld->flags &
+ PNFS_LAYOUTRET_ON_ERROR) {
+ pnfs_return_layout(hdr->inode);
+ }
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags))
+ hdr->task.tk_status = pnfs_read_done_resend_to_mds(hdr);
+}
+
+/*
+ * Called by non rpc-based layout drivers
+ */
+void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
+{
+ trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
+ if (likely(!hdr->pnfs_error)) {
+ __nfs4_read_done_cb(hdr);
+ hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
+ } else
+ pnfs_ld_handle_read_error(hdr);
+ hdr->mds_ops->rpc_release(hdr);
+}
+EXPORT_SYMBOL_GPL(pnfs_ld_read_done);
+
+static void
+pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
+ struct nfs_pgio_header *hdr)
+{
+ struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
+
+ if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+ list_splice_tail_init(&hdr->pages, &mirror->pg_list);
+ nfs_pageio_reset_read_mds(desc);
+ mirror->pg_recoalesce = 1;
+ }
+ nfs_pgio_data_destroy(hdr);
+ hdr->release(hdr);
+}
+
+/*
+ * Call the appropriate parallel I/O subsystem read function.
+ */
+static enum pnfs_try_status
+pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
+ const struct rpc_call_ops *call_ops,
+ struct pnfs_layout_segment *lseg)
+{
+ struct inode *inode = hdr->inode;
+ struct nfs_server *nfss = NFS_SERVER(inode);
+ enum pnfs_try_status trypnfs;
+
+ hdr->mds_ops = call_ops;
+
+ dprintk("%s: Reading ino:%lu %u@%llu\n",
+ __func__, inode->i_ino, hdr->args.count, hdr->args.offset);
+
+ trypnfs = nfss->pnfs_curr_ld->read_pagelist(hdr);
+ if (trypnfs != PNFS_NOT_ATTEMPTED)
+ nfs_inc_stats(inode, NFSIOS_PNFS_READ);
+ dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs);
+ return trypnfs;
+}
+
+/* Resend all requests through pnfs. */
+int pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
+{
+ struct nfs_pageio_descriptor pgio;
+
+ nfs_pageio_init_read(&pgio, hdr->inode, false, hdr->completion_ops);
+ return nfs_pageio_resend(&pgio, hdr);
+}
+EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
+
+static void
+pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
+{
+ const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
+ struct pnfs_layout_segment *lseg = desc->pg_lseg;
+ enum pnfs_try_status trypnfs;
+ int err = 0;
+
+ trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
+ if (trypnfs == PNFS_TRY_AGAIN)
+ err = pnfs_read_resend_pnfs(hdr);
+ if (trypnfs == PNFS_NOT_ATTEMPTED || err)
+ pnfs_read_through_mds(desc, hdr);
+}
+
+static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
+{
+ pnfs_put_lseg(hdr->lseg);
+ nfs_pgio_header_free(hdr);
+}
+
+int
+pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
+{
+ struct nfs_pgio_mirror *mirror = nfs_pgio_current_mirror(desc);
+
+ struct nfs_pgio_header *hdr;
+ int ret;
+
+ hdr = nfs_pgio_header_alloc(desc->pg_rw_ops);
+ if (!hdr) {
+ desc->pg_completion_ops->error_cleanup(&mirror->pg_list);
+ return -ENOMEM;
+ }
+ nfs_pgheader_init(desc, hdr, pnfs_readhdr_free);
+ hdr->lseg = pnfs_get_lseg(desc->pg_lseg);
+ ret = nfs_generic_pgio(desc, hdr);
+ if (!ret)
+ pnfs_do_read(desc, hdr);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_pg_readpages);
+
+static void pnfs_clear_layoutcommitting(struct inode *inode)
+{
+ unsigned long *bitlock = &NFS_I(inode)->flags;
+
+ clear_bit_unlock(NFS_INO_LAYOUTCOMMITTING, bitlock);
+ smp_mb__after_atomic();
+ wake_up_bit(bitlock, NFS_INO_LAYOUTCOMMITTING);
+}
+
+/*
+ * 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_and_clear_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags))
+ list_add(&lseg->pls_lc_list, listp);
+ }
+}
+
+static void pnfs_list_write_lseg_done(struct inode *inode, struct list_head *listp)
+{
+ struct pnfs_layout_segment *lseg, *tmp;
+
+ /* Matched by references in pnfs_set_layoutcommit */
+ list_for_each_entry_safe(lseg, tmp, listp, pls_lc_list) {
+ list_del_init(&lseg->pls_lc_list);
+ pnfs_put_lseg(lseg);
+ }
+
+ pnfs_clear_layoutcommitting(inode);
+}
+
+void pnfs_set_lo_fail(struct pnfs_layout_segment *lseg)
+{
+ pnfs_layout_io_set_failed(lseg->pls_layout, lseg->pls_range.iomode);
+}
+EXPORT_SYMBOL_GPL(pnfs_set_lo_fail);
+
+void
+pnfs_set_layoutcommit(struct inode *inode, struct pnfs_layout_segment *lseg,
+ loff_t end_pos)
+{
+ struct nfs_inode *nfsi = NFS_I(inode);
+ bool mark_as_dirty = false;
+
+ spin_lock(&inode->i_lock);
+ if (!test_and_set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) {
+ nfsi->layout->plh_lwb = end_pos;
+ mark_as_dirty = true;
+ dprintk("%s: Set layoutcommit for inode %lu ",
+ __func__, inode->i_ino);
+ } else if (end_pos > nfsi->layout->plh_lwb)
+ nfsi->layout->plh_lwb = end_pos;
+ if (!test_and_set_bit(NFS_LSEG_LAYOUTCOMMIT, &lseg->pls_flags)) {
+ /* references matched in nfs4_layoutcommit_release */
+ pnfs_get_lseg(lseg);
+ }
+ spin_unlock(&inode->i_lock);
+ dprintk("%s: lseg %p end_pos %llu\n",
+ __func__, 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(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);
+ pnfs_list_write_lseg_done(data->args.inode, &data->lseg_list);
+}
+
+/*
+ * 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 pnfs_layoutdriver_type *ld = NFS_SERVER(inode)->pnfs_curr_ld;
+ struct nfs4_layoutcommit_data *data;
+ struct nfs_inode *nfsi = NFS_I(inode);
+ loff_t end_pos;
+ int status;
+
+ if (!pnfs_layoutcommit_outstanding(inode))
+ return 0;
+
+ dprintk("--> %s inode %lu\n", __func__, inode->i_ino);
+
+ status = -EAGAIN;
+ if (test_and_set_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) {
+ if (!sync)
+ goto out;
+ status = wait_on_bit_lock_action(&nfsi->flags,
+ NFS_INO_LAYOUTCOMMITTING,
+ nfs_wait_bit_killable,
+ TASK_KILLABLE);
+ if (status)
+ goto out;
+ }
+
+ status = -ENOMEM;
+ /* Note kzalloc ensures data->res.seq_res.sr_slot == NULL */
+ data = kzalloc(sizeof(*data), GFP_NOFS);
+ if (!data)
+ goto clear_layoutcommitting;
+
+ status = 0;
+ spin_lock(&inode->i_lock);
+ if (!test_and_clear_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags))
+ goto out_unlock;
+
+ INIT_LIST_HEAD(&data->lseg_list);
+ pnfs_list_write_lseg(inode, &data->lseg_list);
+
+ end_pos = nfsi->layout->plh_lwb;
+
+ 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);
+
+ if (ld->prepare_layoutcommit) {
+ status = ld->prepare_layoutcommit(&data->args);
+ if (status) {
+ spin_lock(&inode->i_lock);
+ set_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags);
+ if (end_pos > nfsi->layout->plh_lwb)
+ nfsi->layout->plh_lwb = end_pos;
+ spin_unlock(&inode->i_lock);
+ put_rpccred(data->cred);
+ goto clear_layoutcommitting;
+ }
+ }
+
+
+ status = nfs4_proc_layoutcommit(data, sync);
+out:
+ if (status)
+ mark_inode_dirty_sync(inode);
+ dprintk("<-- %s status %d\n", __func__, status);
+ return status;
+out_unlock:
+ spin_unlock(&inode->i_lock);
+ kfree(data);
+clear_layoutcommitting:
+ pnfs_clear_layoutcommitting(inode);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(pnfs_layoutcommit_inode);
+
+int
+pnfs_generic_sync(struct inode *inode, bool datasync)
+{
+ return pnfs_layoutcommit_inode(inode, true);
+}
+EXPORT_SYMBOL_GPL(pnfs_generic_sync);
+
+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;
+}