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-rw-r--r--fs/nfs/filelayout/filelayoutdev.c843
1 files changed, 843 insertions, 0 deletions
diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c
new file mode 100644
index 000000000000..44bf0140a4c7
--- /dev/null
+++ b/fs/nfs/filelayout/filelayoutdev.c
@@ -0,0 +1,843 @@
+/*
+ * Device operations for the pnfs nfs4 file layout driver.
+ *
+ * Copyright (c) 2002
+ * The Regents of the University of Michigan
+ * All Rights Reserved
+ *
+ * Dean Hildebrand <dhildebz@umich.edu>
+ * Garth Goodson <Garth.Goodson@netapp.com>
+ *
+ * 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/vmalloc.h>
+#include <linux/module.h>
+#include <linux/sunrpc/addr.h>
+
+#include "../internal.h"
+#include "../nfs4session.h"
+#include "filelayout.h"
+
+#define NFSDBG_FACILITY NFSDBG_PNFS_LD
+
+static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
+static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
+
+/*
+ * Data server cache
+ *
+ * Data servers can be mapped to different device ids.
+ * nfs4_pnfs_ds reference counting
+ * - set to 1 on allocation
+ * - incremented when a device id maps a data server already in the cache.
+ * - decremented when deviceid is removed from the cache.
+ */
+static DEFINE_SPINLOCK(nfs4_ds_cache_lock);
+static LIST_HEAD(nfs4_data_server_cache);
+
+/* Debug routines */
+void
+print_ds(struct nfs4_pnfs_ds *ds)
+{
+ if (ds == NULL) {
+ printk("%s NULL device\n", __func__);
+ return;
+ }
+ printk(" ds %s\n"
+ " ref count %d\n"
+ " client %p\n"
+ " cl_exchange_flags %x\n",
+ ds->ds_remotestr,
+ atomic_read(&ds->ds_count), ds->ds_clp,
+ ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
+}
+
+static bool
+same_sockaddr(struct sockaddr *addr1, struct sockaddr *addr2)
+{
+ struct sockaddr_in *a, *b;
+ struct sockaddr_in6 *a6, *b6;
+
+ if (addr1->sa_family != addr2->sa_family)
+ return false;
+
+ switch (addr1->sa_family) {
+ case AF_INET:
+ a = (struct sockaddr_in *)addr1;
+ b = (struct sockaddr_in *)addr2;
+
+ if (a->sin_addr.s_addr == b->sin_addr.s_addr &&
+ a->sin_port == b->sin_port)
+ return true;
+ break;
+
+ case AF_INET6:
+ a6 = (struct sockaddr_in6 *)addr1;
+ b6 = (struct sockaddr_in6 *)addr2;
+
+ /* LINKLOCAL addresses must have matching scope_id */
+ if (ipv6_addr_src_scope(&a6->sin6_addr) ==
+ IPV6_ADDR_SCOPE_LINKLOCAL &&
+ a6->sin6_scope_id != b6->sin6_scope_id)
+ return false;
+
+ if (ipv6_addr_equal(&a6->sin6_addr, &b6->sin6_addr) &&
+ a6->sin6_port == b6->sin6_port)
+ return true;
+ break;
+
+ default:
+ dprintk("%s: unhandled address family: %u\n",
+ __func__, addr1->sa_family);
+ return false;
+ }
+
+ return false;
+}
+
+static bool
+_same_data_server_addrs_locked(const struct list_head *dsaddrs1,
+ const struct list_head *dsaddrs2)
+{
+ struct nfs4_pnfs_ds_addr *da1, *da2;
+
+ /* step through both lists, comparing as we go */
+ for (da1 = list_first_entry(dsaddrs1, typeof(*da1), da_node),
+ da2 = list_first_entry(dsaddrs2, typeof(*da2), da_node);
+ da1 != NULL && da2 != NULL;
+ da1 = list_entry(da1->da_node.next, typeof(*da1), da_node),
+ da2 = list_entry(da2->da_node.next, typeof(*da2), da_node)) {
+ if (!same_sockaddr((struct sockaddr *)&da1->da_addr,
+ (struct sockaddr *)&da2->da_addr))
+ return false;
+ }
+ if (da1 == NULL && da2 == NULL)
+ return true;
+
+ return false;
+}
+
+/*
+ * Lookup DS by addresses. nfs4_ds_cache_lock is held
+ */
+static struct nfs4_pnfs_ds *
+_data_server_lookup_locked(const struct list_head *dsaddrs)
+{
+ struct nfs4_pnfs_ds *ds;
+
+ list_for_each_entry(ds, &nfs4_data_server_cache, ds_node)
+ if (_same_data_server_addrs_locked(&ds->ds_addrs, dsaddrs))
+ return ds;
+ return NULL;
+}
+
+/*
+ * Create an rpc connection to the nfs4_pnfs_ds data server
+ * Currently only supports IPv4 and IPv6 addresses
+ */
+static int
+nfs4_ds_connect(struct nfs_server *mds_srv, struct nfs4_pnfs_ds *ds)
+{
+ struct nfs_client *clp = ERR_PTR(-EIO);
+ struct nfs4_pnfs_ds_addr *da;
+ int status = 0;
+
+ dprintk("--> %s DS %s au_flavor %d\n", __func__, ds->ds_remotestr,
+ mds_srv->nfs_client->cl_rpcclient->cl_auth->au_flavor);
+
+ list_for_each_entry(da, &ds->ds_addrs, da_node) {
+ dprintk("%s: DS %s: trying address %s\n",
+ __func__, ds->ds_remotestr, da->da_remotestr);
+
+ clp = nfs4_set_ds_client(mds_srv->nfs_client,
+ (struct sockaddr *)&da->da_addr,
+ da->da_addrlen, IPPROTO_TCP,
+ dataserver_timeo, dataserver_retrans);
+ if (!IS_ERR(clp))
+ break;
+ }
+
+ if (IS_ERR(clp)) {
+ status = PTR_ERR(clp);
+ goto out;
+ }
+
+ status = nfs4_init_ds_session(clp, mds_srv->nfs_client->cl_lease_time);
+ if (status)
+ goto out_put;
+
+ smp_wmb();
+ ds->ds_clp = clp;
+ dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
+out:
+ return status;
+out_put:
+ nfs_put_client(clp);
+ goto out;
+}
+
+static void
+destroy_ds(struct nfs4_pnfs_ds *ds)
+{
+ struct nfs4_pnfs_ds_addr *da;
+
+ dprintk("--> %s\n", __func__);
+ ifdebug(FACILITY)
+ print_ds(ds);
+
+ if (ds->ds_clp)
+ nfs_put_client(ds->ds_clp);
+
+ while (!list_empty(&ds->ds_addrs)) {
+ da = list_first_entry(&ds->ds_addrs,
+ struct nfs4_pnfs_ds_addr,
+ da_node);
+ list_del_init(&da->da_node);
+ kfree(da->da_remotestr);
+ kfree(da);
+ }
+
+ kfree(ds->ds_remotestr);
+ kfree(ds);
+}
+
+void
+nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
+{
+ struct nfs4_pnfs_ds *ds;
+ int i;
+
+ nfs4_print_deviceid(&dsaddr->id_node.deviceid);
+
+ for (i = 0; i < dsaddr->ds_num; i++) {
+ ds = dsaddr->ds_list[i];
+ if (ds != NULL) {
+ if (atomic_dec_and_lock(&ds->ds_count,
+ &nfs4_ds_cache_lock)) {
+ list_del_init(&ds->ds_node);
+ spin_unlock(&nfs4_ds_cache_lock);
+ destroy_ds(ds);
+ }
+ }
+ }
+ kfree(dsaddr->stripe_indices);
+ kfree(dsaddr);
+}
+
+/*
+ * Create a string with a human readable address and port to avoid
+ * complicated setup around many dprinks.
+ */
+static char *
+nfs4_pnfs_remotestr(struct list_head *dsaddrs, gfp_t gfp_flags)
+{
+ struct nfs4_pnfs_ds_addr *da;
+ char *remotestr;
+ size_t len;
+ char *p;
+
+ len = 3; /* '{', '}' and eol */
+ list_for_each_entry(da, dsaddrs, da_node) {
+ len += strlen(da->da_remotestr) + 1; /* string plus comma */
+ }
+
+ remotestr = kzalloc(len, gfp_flags);
+ if (!remotestr)
+ return NULL;
+
+ p = remotestr;
+ *(p++) = '{';
+ len--;
+ list_for_each_entry(da, dsaddrs, da_node) {
+ size_t ll = strlen(da->da_remotestr);
+
+ if (ll > len)
+ goto out_err;
+
+ memcpy(p, da->da_remotestr, ll);
+ p += ll;
+ len -= ll;
+
+ if (len < 1)
+ goto out_err;
+ (*p++) = ',';
+ len--;
+ }
+ if (len < 2)
+ goto out_err;
+ *(p++) = '}';
+ *p = '\0';
+ return remotestr;
+out_err:
+ kfree(remotestr);
+ return NULL;
+}
+
+static struct nfs4_pnfs_ds *
+nfs4_pnfs_ds_add(struct list_head *dsaddrs, gfp_t gfp_flags)
+{
+ struct nfs4_pnfs_ds *tmp_ds, *ds = NULL;
+ char *remotestr;
+
+ if (list_empty(dsaddrs)) {
+ dprintk("%s: no addresses defined\n", __func__);
+ goto out;
+ }
+
+ ds = kzalloc(sizeof(*ds), gfp_flags);
+ if (!ds)
+ goto out;
+
+ /* this is only used for debugging, so it's ok if its NULL */
+ remotestr = nfs4_pnfs_remotestr(dsaddrs, gfp_flags);
+
+ spin_lock(&nfs4_ds_cache_lock);
+ tmp_ds = _data_server_lookup_locked(dsaddrs);
+ if (tmp_ds == NULL) {
+ INIT_LIST_HEAD(&ds->ds_addrs);
+ list_splice_init(dsaddrs, &ds->ds_addrs);
+ ds->ds_remotestr = remotestr;
+ atomic_set(&ds->ds_count, 1);
+ INIT_LIST_HEAD(&ds->ds_node);
+ ds->ds_clp = NULL;
+ list_add(&ds->ds_node, &nfs4_data_server_cache);
+ dprintk("%s add new data server %s\n", __func__,
+ ds->ds_remotestr);
+ } else {
+ kfree(remotestr);
+ kfree(ds);
+ atomic_inc(&tmp_ds->ds_count);
+ dprintk("%s data server %s found, inc'ed ds_count to %d\n",
+ __func__, tmp_ds->ds_remotestr,
+ atomic_read(&tmp_ds->ds_count));
+ ds = tmp_ds;
+ }
+ spin_unlock(&nfs4_ds_cache_lock);
+out:
+ return ds;
+}
+
+/*
+ * Currently only supports ipv4, ipv6 and one multi-path address.
+ */
+static struct nfs4_pnfs_ds_addr *
+decode_ds_addr(struct net *net, struct xdr_stream *streamp, gfp_t gfp_flags)
+{
+ struct nfs4_pnfs_ds_addr *da = NULL;
+ char *buf, *portstr;
+ __be16 port;
+ int nlen, rlen;
+ int tmp[2];
+ __be32 *p;
+ char *netid, *match_netid;
+ size_t len, match_netid_len;
+ char *startsep = "";
+ char *endsep = "";
+
+
+ /* r_netid */
+ p = xdr_inline_decode(streamp, 4);
+ if (unlikely(!p))
+ goto out_err;
+ nlen = be32_to_cpup(p++);
+
+ p = xdr_inline_decode(streamp, nlen);
+ if (unlikely(!p))
+ goto out_err;
+
+ netid = kmalloc(nlen+1, gfp_flags);
+ if (unlikely(!netid))
+ goto out_err;
+
+ netid[nlen] = '\0';
+ memcpy(netid, p, nlen);
+
+ /* r_addr: ip/ip6addr with port in dec octets - see RFC 5665 */
+ p = xdr_inline_decode(streamp, 4);
+ if (unlikely(!p))
+ goto out_free_netid;
+ rlen = be32_to_cpup(p);
+
+ p = xdr_inline_decode(streamp, rlen);
+ if (unlikely(!p))
+ goto out_free_netid;
+
+ /* port is ".ABC.DEF", 8 chars max */
+ if (rlen > INET6_ADDRSTRLEN + IPV6_SCOPE_ID_LEN + 8) {
+ dprintk("%s: Invalid address, length %d\n", __func__,
+ rlen);
+ goto out_free_netid;
+ }
+ buf = kmalloc(rlen + 1, gfp_flags);
+ if (!buf) {
+ dprintk("%s: Not enough memory\n", __func__);
+ goto out_free_netid;
+ }
+ buf[rlen] = '\0';
+ memcpy(buf, p, rlen);
+
+ /* replace port '.' with '-' */
+ portstr = strrchr(buf, '.');
+ if (!portstr) {
+ dprintk("%s: Failed finding expected dot in port\n",
+ __func__);
+ goto out_free_buf;
+ }
+ *portstr = '-';
+
+ /* find '.' between address and port */
+ portstr = strrchr(buf, '.');
+ if (!portstr) {
+ dprintk("%s: Failed finding expected dot between address and "
+ "port\n", __func__);
+ goto out_free_buf;
+ }
+ *portstr = '\0';
+
+ da = kzalloc(sizeof(*da), gfp_flags);
+ if (unlikely(!da))
+ goto out_free_buf;
+
+ INIT_LIST_HEAD(&da->da_node);
+
+ if (!rpc_pton(net, buf, portstr-buf, (struct sockaddr *)&da->da_addr,
+ sizeof(da->da_addr))) {
+ dprintk("%s: error parsing address %s\n", __func__, buf);
+ goto out_free_da;
+ }
+
+ portstr++;
+ sscanf(portstr, "%d-%d", &tmp[0], &tmp[1]);
+ port = htons((tmp[0] << 8) | (tmp[1]));
+
+ switch (da->da_addr.ss_family) {
+ case AF_INET:
+ ((struct sockaddr_in *)&da->da_addr)->sin_port = port;
+ da->da_addrlen = sizeof(struct sockaddr_in);
+ match_netid = "tcp";
+ match_netid_len = 3;
+ break;
+
+ case AF_INET6:
+ ((struct sockaddr_in6 *)&da->da_addr)->sin6_port = port;
+ da->da_addrlen = sizeof(struct sockaddr_in6);
+ match_netid = "tcp6";
+ match_netid_len = 4;
+ startsep = "[";
+ endsep = "]";
+ break;
+
+ default:
+ dprintk("%s: unsupported address family: %u\n",
+ __func__, da->da_addr.ss_family);
+ goto out_free_da;
+ }
+
+ if (nlen != match_netid_len || strncmp(netid, match_netid, nlen)) {
+ dprintk("%s: ERROR: r_netid \"%s\" != \"%s\"\n",
+ __func__, netid, match_netid);
+ goto out_free_da;
+ }
+
+ /* save human readable address */
+ len = strlen(startsep) + strlen(buf) + strlen(endsep) + 7;
+ da->da_remotestr = kzalloc(len, gfp_flags);
+
+ /* NULL is ok, only used for dprintk */
+ if (da->da_remotestr)
+ snprintf(da->da_remotestr, len, "%s%s%s:%u", startsep,
+ buf, endsep, ntohs(port));
+
+ dprintk("%s: Parsed DS addr %s\n", __func__, da->da_remotestr);
+ kfree(buf);
+ kfree(netid);
+ return da;
+
+out_free_da:
+ kfree(da);
+out_free_buf:
+ dprintk("%s: Error parsing DS addr: %s\n", __func__, buf);
+ kfree(buf);
+out_free_netid:
+ kfree(netid);
+out_err:
+ return NULL;
+}
+
+/* Decode opaque device data and return the result */
+static struct nfs4_file_layout_dsaddr*
+decode_device(struct inode *ino, struct pnfs_device *pdev, gfp_t gfp_flags)
+{
+ int i;
+ u32 cnt, num;
+ u8 *indexp;
+ __be32 *p;
+ u8 *stripe_indices;
+ u8 max_stripe_index;
+ struct nfs4_file_layout_dsaddr *dsaddr = NULL;
+ struct xdr_stream stream;
+ struct xdr_buf buf;
+ struct page *scratch;
+ struct list_head dsaddrs;
+ struct nfs4_pnfs_ds_addr *da;
+
+ /* set up xdr stream */
+ scratch = alloc_page(gfp_flags);
+ if (!scratch)
+ goto out_err;
+
+ xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
+ xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
+
+ /* Get the stripe count (number of stripe index) */
+ p = xdr_inline_decode(&stream, 4);
+ if (unlikely(!p))
+ goto out_err_free_scratch;
+
+ cnt = be32_to_cpup(p);
+ dprintk("%s stripe count %d\n", __func__, cnt);
+ if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
+ printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
+ "supported maximum %d\n", __func__,
+ cnt, NFS4_PNFS_MAX_STRIPE_CNT);
+ goto out_err_free_scratch;
+ }
+
+ /* read stripe indices */
+ stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
+ if (!stripe_indices)
+ goto out_err_free_scratch;
+
+ p = xdr_inline_decode(&stream, cnt << 2);
+ if (unlikely(!p))
+ goto out_err_free_stripe_indices;
+
+ indexp = &stripe_indices[0];
+ max_stripe_index = 0;
+ for (i = 0; i < cnt; i++) {
+ *indexp = be32_to_cpup(p++);
+ max_stripe_index = max(max_stripe_index, *indexp);
+ indexp++;
+ }
+
+ /* Check the multipath list count */
+ p = xdr_inline_decode(&stream, 4);
+ if (unlikely(!p))
+ goto out_err_free_stripe_indices;
+
+ num = be32_to_cpup(p);
+ dprintk("%s ds_num %u\n", __func__, num);
+ if (num > NFS4_PNFS_MAX_MULTI_CNT) {
+ printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
+ "supported maximum %d\n", __func__,
+ num, NFS4_PNFS_MAX_MULTI_CNT);
+ goto out_err_free_stripe_indices;
+ }
+
+ /* validate stripe indices are all < num */
+ if (max_stripe_index >= num) {
+ printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
+ __func__, max_stripe_index, num);
+ goto out_err_free_stripe_indices;
+ }
+
+ dsaddr = kzalloc(sizeof(*dsaddr) +
+ (sizeof(struct nfs4_pnfs_ds *) * (num - 1)),
+ gfp_flags);
+ if (!dsaddr)
+ goto out_err_free_stripe_indices;
+
+ dsaddr->stripe_count = cnt;
+ dsaddr->stripe_indices = stripe_indices;
+ stripe_indices = NULL;
+ dsaddr->ds_num = num;
+ nfs4_init_deviceid_node(&dsaddr->id_node,
+ NFS_SERVER(ino)->pnfs_curr_ld,
+ NFS_SERVER(ino)->nfs_client,
+ &pdev->dev_id);
+
+ INIT_LIST_HEAD(&dsaddrs);
+
+ for (i = 0; i < dsaddr->ds_num; i++) {
+ int j;
+ u32 mp_count;
+
+ p = xdr_inline_decode(&stream, 4);
+ if (unlikely(!p))
+ goto out_err_free_deviceid;
+
+ mp_count = be32_to_cpup(p); /* multipath count */
+ for (j = 0; j < mp_count; j++) {
+ da = decode_ds_addr(NFS_SERVER(ino)->nfs_client->cl_net,
+ &stream, gfp_flags);
+ if (da)
+ list_add_tail(&da->da_node, &dsaddrs);
+ }
+ if (list_empty(&dsaddrs)) {
+ dprintk("%s: no suitable DS addresses found\n",
+ __func__);
+ goto out_err_free_deviceid;
+ }
+
+ dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
+ if (!dsaddr->ds_list[i])
+ goto out_err_drain_dsaddrs;
+
+ /* If DS was already in cache, free ds addrs */
+ while (!list_empty(&dsaddrs)) {
+ da = list_first_entry(&dsaddrs,
+ struct nfs4_pnfs_ds_addr,
+ da_node);
+ list_del_init(&da->da_node);
+ kfree(da->da_remotestr);
+ kfree(da);
+ }
+ }
+
+ __free_page(scratch);
+ return dsaddr;
+
+out_err_drain_dsaddrs:
+ while (!list_empty(&dsaddrs)) {
+ da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
+ da_node);
+ list_del_init(&da->da_node);
+ kfree(da->da_remotestr);
+ kfree(da);
+ }
+out_err_free_deviceid:
+ nfs4_fl_free_deviceid(dsaddr);
+ /* stripe_indicies was part of dsaddr */
+ goto out_err_free_scratch;
+out_err_free_stripe_indices:
+ kfree(stripe_indices);
+out_err_free_scratch:
+ __free_page(scratch);
+out_err:
+ dprintk("%s ERROR: returning NULL\n", __func__);
+ return NULL;
+}
+
+/*
+ * Decode the opaque device specified in 'dev' and add it to the cache of
+ * available devices.
+ */
+static struct nfs4_file_layout_dsaddr *
+decode_and_add_device(struct inode *inode, struct pnfs_device *dev, gfp_t gfp_flags)
+{
+ struct nfs4_deviceid_node *d;
+ struct nfs4_file_layout_dsaddr *n, *new;
+
+ new = decode_device(inode, dev, gfp_flags);
+ if (!new) {
+ printk(KERN_WARNING "NFS: %s: Could not decode or add device\n",
+ __func__);
+ return NULL;
+ }
+
+ d = nfs4_insert_deviceid_node(&new->id_node);
+ n = container_of(d, struct nfs4_file_layout_dsaddr, id_node);
+ if (n != new) {
+ nfs4_fl_free_deviceid(new);
+ return n;
+ }
+
+ return new;
+}
+
+/*
+ * Retrieve the information for dev_id, add it to the list
+ * of available devices, and return it.
+ */
+struct nfs4_file_layout_dsaddr *
+filelayout_get_device_info(struct inode *inode,
+ struct nfs4_deviceid *dev_id,
+ struct rpc_cred *cred,
+ gfp_t gfp_flags)
+{
+ struct pnfs_device *pdev = NULL;
+ u32 max_resp_sz;
+ int max_pages;
+ struct page **pages = NULL;
+ struct nfs4_file_layout_dsaddr *dsaddr = NULL;
+ int rc, i;
+ struct nfs_server *server = NFS_SERVER(inode);
+
+ /*
+ * Use the session max response size as the basis for setting
+ * GETDEVICEINFO's maxcount
+ */
+ max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
+ max_pages = nfs_page_array_len(0, max_resp_sz);
+ dprintk("%s inode %p max_resp_sz %u max_pages %d\n",
+ __func__, inode, max_resp_sz, max_pages);
+
+ pdev = kzalloc(sizeof(struct pnfs_device), gfp_flags);
+ if (pdev == NULL)
+ return NULL;
+
+ pages = kzalloc(max_pages * sizeof(struct page *), gfp_flags);
+ if (pages == NULL) {
+ kfree(pdev);
+ return NULL;
+ }
+ for (i = 0; i < max_pages; i++) {
+ pages[i] = alloc_page(gfp_flags);
+ if (!pages[i])
+ goto out_free;
+ }
+
+ memcpy(&pdev->dev_id, dev_id, sizeof(*dev_id));
+ pdev->layout_type = LAYOUT_NFSV4_1_FILES;
+ pdev->pages = pages;
+ pdev->pgbase = 0;
+ pdev->pglen = max_resp_sz;
+ pdev->mincount = 0;
+ pdev->maxcount = max_resp_sz - nfs41_maxgetdevinfo_overhead;
+
+ rc = nfs4_proc_getdeviceinfo(server, pdev, cred);
+ dprintk("%s getdevice info returns %d\n", __func__, rc);
+ if (rc)
+ goto out_free;
+
+ /*
+ * Found new device, need to decode it and then add it to the
+ * list of known devices for this mountpoint.
+ */
+ dsaddr = decode_and_add_device(inode, pdev, gfp_flags);
+out_free:
+ for (i = 0; i < max_pages; i++)
+ __free_page(pages[i]);
+ kfree(pages);
+ kfree(pdev);
+ dprintk("<-- %s dsaddr %p\n", __func__, dsaddr);
+ return dsaddr;
+}
+
+void
+nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
+{
+ nfs4_put_deviceid_node(&dsaddr->id_node);
+}
+
+/*
+ * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
+ * Then: ((res + fsi) % dsaddr->stripe_count)
+ */
+u32
+nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
+{
+ struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+ u64 tmp;
+
+ tmp = offset - flseg->pattern_offset;
+ do_div(tmp, flseg->stripe_unit);
+ tmp += flseg->first_stripe_index;
+ return do_div(tmp, flseg->dsaddr->stripe_count);
+}
+
+u32
+nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
+{
+ return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
+}
+
+struct nfs_fh *
+nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
+{
+ struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
+ u32 i;
+
+ if (flseg->stripe_type == STRIPE_SPARSE) {
+ if (flseg->num_fh == 1)
+ i = 0;
+ else if (flseg->num_fh == 0)
+ /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
+ return NULL;
+ else
+ i = nfs4_fl_calc_ds_index(lseg, j);
+ } else
+ i = j;
+ return flseg->fh_array[i];
+}
+
+static void nfs4_wait_ds_connect(struct nfs4_pnfs_ds *ds)
+{
+ might_sleep();
+ wait_on_bit(&ds->ds_state, NFS4DS_CONNECTING,
+ nfs_wait_bit_killable, TASK_KILLABLE);
+}
+
+static void nfs4_clear_ds_conn_bit(struct nfs4_pnfs_ds *ds)
+{
+ smp_mb__before_atomic();
+ clear_bit(NFS4DS_CONNECTING, &ds->ds_state);
+ smp_mb__after_atomic();
+ wake_up_bit(&ds->ds_state, NFS4DS_CONNECTING);
+}
+
+
+struct nfs4_pnfs_ds *
+nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
+{
+ struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
+ struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
+ struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
+ struct nfs4_pnfs_ds *ret = ds;
+
+ if (ds == NULL) {
+ printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
+ __func__, ds_idx);
+ filelayout_mark_devid_invalid(devid);
+ goto out;
+ }
+ smp_rmb();
+ if (ds->ds_clp)
+ goto out_test_devid;
+
+ if (test_and_set_bit(NFS4DS_CONNECTING, &ds->ds_state) == 0) {
+ struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
+ int err;
+
+ err = nfs4_ds_connect(s, ds);
+ if (err)
+ nfs4_mark_deviceid_unavailable(devid);
+ nfs4_clear_ds_conn_bit(ds);
+ } else {
+ /* Either ds is connected, or ds is NULL */
+ nfs4_wait_ds_connect(ds);
+ }
+out_test_devid:
+ if (filelayout_test_devid_unavailable(devid))
+ ret = NULL;
+out:
+ return ret;
+}
+
+module_param(dataserver_retrans, uint, 0644);
+MODULE_PARM_DESC(dataserver_retrans, "The number of times the NFSv4.1 client "
+ "retries a request before it attempts further "
+ " recovery action.");
+module_param(dataserver_timeo, uint, 0644);
+MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
+ "NFSv4.1 client waits for a response from a "
+ " data server before it retries an NFS request.");