LXR linux/fs/nfs/filelayout/filelayoutdev.c

   1/*
   2 *  Device operations for the pnfs nfs4 file layout driver.
   3 *
   4 *  Copyright (c) 2002
   5 *  The Regents of the University of Michigan
   6 *  All Rights Reserved
   7 *
   8 *  Dean Hildebrand <dhildebz@umich.edu>
   9 *  Garth Goodson   <Garth.Goodson@netapp.com>
  10 *
  11 *  Permission is granted to use, copy, create derivative works, and
  12 *  redistribute this software and such derivative works for any purpose,
  13 *  so long as the name of the University of Michigan is not used in
  14 *  any advertising or publicity pertaining to the use or distribution
  15 *  of this software without specific, written prior authorization. If
  16 *  the above copyright notice or any other identification of the
  17 *  University of Michigan is included in any copy of any portion of
  18 *  this software, then the disclaimer below must also be included.
  19 *
  20 *  This software is provided as is, without representation or warranty
  21 *  of any kind either express or implied, including without limitation
  22 *  the implied warranties of merchantability, fitness for a particular
  23 *  purpose, or noninfringement.  The Regents of the University of
  24 *  Michigan shall not be liable for any damages, including special,
  25 *  indirect, incidental, or consequential damages, with respect to any
  26 *  claim arising out of or in connection with the use of the software,
  27 *  even if it has been or is hereafter advised of the possibility of
  28 *  such damages.
  29 */
  30
  31#include <linux/nfs_fs.h>
  32#include <linux/vmalloc.h>
  33#include <linux/module.h>
  34
  35#include "../internal.h"
  36#include "../nfs4session.h"
  37#include "filelayout.h"
  38
  39#define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  40
  41static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
  42static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
  43
  44void
  45nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
  46{
  47        struct nfs4_pnfs_ds *ds;
  48        int i;
  49
  50        nfs4_print_deviceid(&dsaddr->id_node.deviceid);
  51
  52        for (i = 0; i < dsaddr->ds_num; i++) {
  53                ds = dsaddr->ds_list[i];
  54                if (ds != NULL)
  55                        nfs4_pnfs_ds_put(ds);
  56        }
  57        kfree(dsaddr->stripe_indices);
  58        kfree_rcu(dsaddr, id_node.rcu);
  59}
  60
  61/* Decode opaque device data and return the result */
  62struct nfs4_file_layout_dsaddr *
  63nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
  64                gfp_t gfp_flags)
  65{
  66        int i;
  67        u32 cnt, num;
  68        u8 *indexp;
  69        __be32 *p;
  70        u8 *stripe_indices;
  71        u8 max_stripe_index;
  72        struct nfs4_file_layout_dsaddr *dsaddr = NULL;
  73        struct xdr_stream stream;
  74        struct xdr_buf buf;
  75        struct page *scratch;
  76        struct list_head dsaddrs;
  77        struct nfs4_pnfs_ds_addr *da;
  78
  79        /* set up xdr stream */
  80        scratch = alloc_page(gfp_flags);
  81        if (!scratch)
  82                goto out_err;
  83
  84        xdr_init_decode_pages(&stream, &buf, pdev->pages, pdev->pglen);
  85        xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
  86
  87        /* Get the stripe count (number of stripe index) */
  88        p = xdr_inline_decode(&stream, 4);
  89        if (unlikely(!p))
  90                goto out_err_free_scratch;
  91
  92        cnt = be32_to_cpup(p);
  93        dprintk("%s stripe count  %d\n", __func__, cnt);
  94        if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
  95                printk(KERN_WARNING "NFS: %s: stripe count %d greater than "
  96                       "supported maximum %d\n", __func__,
  97                        cnt, NFS4_PNFS_MAX_STRIPE_CNT);
  98                goto out_err_free_scratch;
  99        }
 100
 101        /* read stripe indices */
 102        stripe_indices = kcalloc(cnt, sizeof(u8), gfp_flags);
 103        if (!stripe_indices)
 104                goto out_err_free_scratch;
 105
 106        p = xdr_inline_decode(&stream, cnt << 2);
 107        if (unlikely(!p))
 108                goto out_err_free_stripe_indices;
 109
 110        indexp = &stripe_indices[0];
 111        max_stripe_index = 0;
 112        for (i = 0; i < cnt; i++) {
 113                *indexp = be32_to_cpup(p++);
 114                max_stripe_index = max(max_stripe_index, *indexp);
 115                indexp++;
 116        }
 117
 118        /* Check the multipath list count */
 119        p = xdr_inline_decode(&stream, 4);
 120        if (unlikely(!p))
 121                goto out_err_free_stripe_indices;
 122
 123        num = be32_to_cpup(p);
 124        dprintk("%s ds_num %u\n", __func__, num);
 125        if (num > NFS4_PNFS_MAX_MULTI_CNT) {
 126                printk(KERN_WARNING "NFS: %s: multipath count %d greater than "
 127                        "supported maximum %d\n", __func__,
 128                        num, NFS4_PNFS_MAX_MULTI_CNT);
 129                goto out_err_free_stripe_indices;
 130        }
 131
 132        /* validate stripe indices are all < num */
 133        if (max_stripe_index >= num) {
 134                printk(KERN_WARNING "NFS: %s: stripe index %u >= num ds %u\n",
 135                        __func__, max_stripe_index, num);
 136                goto out_err_free_stripe_indices;
 137        }
 138
 139        dsaddr = kzalloc(sizeof(*dsaddr) +
 140                        (sizeof(struct nfs4_pnfs_ds *) * (num - 1)),
 141                        gfp_flags);
 142        if (!dsaddr)
 143                goto out_err_free_stripe_indices;
 144
 145        dsaddr->stripe_count = cnt;
 146        dsaddr->stripe_indices = stripe_indices;
 147        stripe_indices = NULL;
 148        dsaddr->ds_num = num;
 149        nfs4_init_deviceid_node(&dsaddr->id_node, server, &pdev->dev_id);
 150
 151        INIT_LIST_HEAD(&dsaddrs);
 152
 153        for (i = 0; i < dsaddr->ds_num; i++) {
 154                int j;
 155                u32 mp_count;
 156
 157                p = xdr_inline_decode(&stream, 4);
 158                if (unlikely(!p))
 159                        goto out_err_free_deviceid;
 160
 161                mp_count = be32_to_cpup(p); /* multipath count */
 162                for (j = 0; j < mp_count; j++) {
 163                        da = nfs4_decode_mp_ds_addr(server->nfs_client->cl_net,
 164                                                    &stream, gfp_flags);
 165                        if (da)
 166                                list_add_tail(&da->da_node, &dsaddrs);
 167                }
 168                if (list_empty(&dsaddrs)) {
 169                        dprintk("%s: no suitable DS addresses found\n",
 170                                __func__);
 171                        goto out_err_free_deviceid;
 172                }
 173
 174                dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
 175                if (!dsaddr->ds_list[i])
 176                        goto out_err_drain_dsaddrs;
 177
 178                /* If DS was already in cache, free ds addrs */
 179                while (!list_empty(&dsaddrs)) {
 180                        da = list_first_entry(&dsaddrs,
 181                                              struct nfs4_pnfs_ds_addr,
 182                                              da_node);
 183                        list_del_init(&da->da_node);
 184                        kfree(da->da_remotestr);
 185                        kfree(da);
 186                }
 187        }
 188
 189        __free_page(scratch);
 190        return dsaddr;
 191
 192out_err_drain_dsaddrs:
 193        while (!list_empty(&dsaddrs)) {
 194                da = list_first_entry(&dsaddrs, struct nfs4_pnfs_ds_addr,
 195                                      da_node);
 196                list_del_init(&da->da_node);
 197                kfree(da->da_remotestr);
 198                kfree(da);
 199        }
 200out_err_free_deviceid:
 201        nfs4_fl_free_deviceid(dsaddr);
 202        /* stripe_indicies was part of dsaddr */
 203        goto out_err_free_scratch;
 204out_err_free_stripe_indices:
 205        kfree(stripe_indices);
 206out_err_free_scratch:
 207        __free_page(scratch);
 208out_err:
 209        dprintk("%s ERROR: returning NULL\n", __func__);
 210        return NULL;
 211}
 212
 213void
 214nfs4_fl_put_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 215{
 216        nfs4_put_deviceid_node(&dsaddr->id_node);
 217}
 218
 219/*
 220 * Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
 221 * Then: ((res + fsi) % dsaddr->stripe_count)
 222 */
 223u32
 224nfs4_fl_calc_j_index(struct pnfs_layout_segment *lseg, loff_t offset)
 225{
 226        struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 227        u64 tmp;
 228
 229        tmp = offset - flseg->pattern_offset;
 230        do_div(tmp, flseg->stripe_unit);
 231        tmp += flseg->first_stripe_index;
 232        return do_div(tmp, flseg->dsaddr->stripe_count);
 233}
 234
 235u32
 236nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
 237{
 238        return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
 239}
 240
 241struct nfs_fh *
 242nfs4_fl_select_ds_fh(struct pnfs_layout_segment *lseg, u32 j)
 243{
 244        struct nfs4_filelayout_segment *flseg = FILELAYOUT_LSEG(lseg);
 245        u32 i;
 246
 247        if (flseg->stripe_type == STRIPE_SPARSE) {
 248                if (flseg->num_fh == 1)
 249                        i = 0;
 250                else if (flseg->num_fh == 0)
 251                        /* Use the MDS OPEN fh set in nfs_read_rpcsetup */
 252                        return NULL;
 253                else
 254                        i = nfs4_fl_calc_ds_index(lseg, j);
 255        } else
 256                i = j;
 257        return flseg->fh_array[i];
 258}
 259
 260/* Upon return, either ds is connected, or ds is NULL */
 261struct nfs4_pnfs_ds *
 262nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
 263{
 264        struct nfs4_file_layout_dsaddr *dsaddr = FILELAYOUT_LSEG(lseg)->dsaddr;
 265        struct nfs4_pnfs_ds *ds = dsaddr->ds_list[ds_idx];
 266        struct nfs4_deviceid_node *devid = FILELAYOUT_DEVID_NODE(lseg);
 267        struct nfs4_pnfs_ds *ret = ds;
 268        struct nfs_server *s = NFS_SERVER(lseg->pls_layout->plh_inode);
 269
 270        if (ds == NULL) {
 271                printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
 272                        __func__, ds_idx);
 273                pnfs_generic_mark_devid_invalid(devid);
 274                goto out;
 275        }
 276        smp_rmb();
 277        if (ds->ds_clp)
 278                goto out_test_devid;
 279
 280        nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
 281                             dataserver_retrans, 4,
 282                             s->nfs_client->cl_minorversion,
 283                             s->nfs_client->cl_rpcclient->cl_auth->au_flavor);
 284
 285out_test_devid:
 286        if (filelayout_test_devid_unavailable(devid))
 287                ret = NULL;
 288out:
 289        return ret;
 290}
 291
 292module_param(dataserver_retrans, uint, 0644);
 293MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
 294                        "retries a request before it attempts further "
 295                        " recovery  action.");
 296module_param(dataserver_timeo, uint, 0644);
 297MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
 298                        "NFSv4.1  client  waits for a response from a "
 299                        " data server before it retries an NFS request.");
 300