root/fs/nfs/filelayout/filelayoutdev.c

DEFINITIONS

1. nfs4_fl_free_deviceid
2. nfs4_fl_alloc_deviceid_node
3. nfs4_fl_put_deviceid
4. nfs4_fl_calc_j_index
5. nfs4_fl_calc_ds_index
6. nfs4_fl_select_ds_fh
7. nfs4_fl_prepare_ds

   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 
  41 static unsigned int dataserver_timeo = NFS4_DEF_DS_TIMEO;
  42 static unsigned int dataserver_retrans = NFS4_DEF_DS_RETRANS;
  43 
  44 void
  45 nfs4_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 */
  62 struct nfs4_file_layout_dsaddr *
  63 nfs4_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 
 192 out_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         }
 200 out_err_free_deviceid:
 201         nfs4_fl_free_deviceid(dsaddr);
 202         /* stripe_indicies was part of dsaddr */
 203         goto out_err_free_scratch;
 204 out_err_free_stripe_indices:
 205         kfree(stripe_indices);
 206 out_err_free_scratch:
 207         __free_page(scratch);
 208 out_err:
 209         dprintk("%s ERROR: returning NULL\n", __func__);
 210         return NULL;
 211 }
 212 
 213 void
 214 nfs4_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  */
 223 u32
 224 nfs4_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 
 235 u32
 236 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, u32 j)
 237 {
 238         return FILELAYOUT_LSEG(lseg)->dsaddr->stripe_indices[j];
 239 }
 240 
 241 struct nfs_fh *
 242 nfs4_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 */
 261 struct nfs4_pnfs_ds *
 262 nfs4_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         int status;
 270 
 271         if (ds == NULL) {
 272                 printk(KERN_ERR "NFS: %s: No data server for offset index %d\n",
 273                         __func__, ds_idx);
 274                 pnfs_generic_mark_devid_invalid(devid);
 275                 goto out;
 276         }
 277         smp_rmb();
 278         if (ds->ds_clp)
 279                 goto out_test_devid;
 280 
 281         status = nfs4_pnfs_ds_connect(s, ds, devid, dataserver_timeo,
 282                              dataserver_retrans, 4,
 283                              s->nfs_client->cl_minorversion);
 284         if (status) {
 285                 nfs4_mark_deviceid_unavailable(devid);
 286                 ret = NULL;
 287                 goto out;
 288         }
 289 
 290 out_test_devid:
 291         if (ret->ds_clp == NULL ||
 292             filelayout_test_devid_unavailable(devid))
 293                 ret = NULL;
 294 out:
 295         return ret;
 296 }
 297 
 298 module_param(dataserver_retrans, uint, 0644);
 299 MODULE_PARM_DESC(dataserver_retrans, "The  number of times the NFSv4.1 client "
 300                         "retries a request before it attempts further "
 301                         " recovery  action.");
 302 module_param(dataserver_timeo, uint, 0644);
 303 MODULE_PARM_DESC(dataserver_timeo, "The time (in tenths of a second) the "
 304                         "NFSv4.1  client  waits for a response from a "
 305                         " data server before it retries an NFS request.");