fs/nfs/nfs4filelayoutdev.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
  34 #include "internal.h"
  35 #include "nfs4filelayout.h"
  36
  37 #define NFSDBG_FACILITY         NFSDBG_PNFS_LD
  38
  39 /*
  40  * Data server cache
  41  *
  42  * Data servers can be mapped to different device ids.
  43  * nfs4_pnfs_ds reference counting
  44  *   - set to 1 on allocation
  45  *   - incremented when a device id maps a data server already in the cache.
  46  *   - decremented when deviceid is removed from the cache.
  47  */
  48 DEFINE_SPINLOCK(nfs4_ds_cache_lock);
  49 static LIST_HEAD(nfs4_data_server_cache);
  50
  51 /* Debug routines */
  52 void
  53 print_ds(struct nfs4_pnfs_ds *ds)
  54 {
  55         if (ds == NULL) {
  56                 printk("%s NULL device\n", __func__);
  57                 return;
  58         }
  59         printk("        ip_addr %x port %hu\n"
  60                 "        ref count %d\n"
  61                 "        client %p\n"
  62                 "        cl_exchange_flags %x\n",
  63                 ntohl(ds->ds_ip_addr), ntohs(ds->ds_port),
  64                 atomic_read(&ds->ds_count), ds->ds_clp,
  65                 ds->ds_clp ? ds->ds_clp->cl_exchange_flags : 0);
  66 }
  67
  68 void
  69 print_ds_list(struct nfs4_file_layout_dsaddr *dsaddr)
  70 {
  71         int i;
  72
  73         ifdebug(FACILITY) {
  74                 printk("%s dsaddr->ds_num %d\n", __func__,
  75                        dsaddr->ds_num);
  76                 for (i = 0; i < dsaddr->ds_num; i++)
  77                         print_ds(dsaddr->ds_list[i]);
  78         }
  79 }
  80
  81 void print_deviceid(struct nfs4_deviceid *id)
  82 {
  83         u32 *p = (u32 *)id;
  84
  85         dprintk("%s: device id= [%x%x%x%x]\n", __func__,
  86                 p[0], p[1], p[2], p[3]);
  87 }
  88
  89 /* nfs4_ds_cache_lock is held */
  90 static struct nfs4_pnfs_ds *
  91 _data_server_lookup_locked(u32 ip_addr, u32 port)
  92 {
  93         struct nfs4_pnfs_ds *ds;
  94
  95         dprintk("_data_server_lookup: ip_addr=%x port=%hu\n",
  96                         ntohl(ip_addr), ntohs(port));
  97
  98         list_for_each_entry(ds, &nfs4_data_server_cache, ds_node) {
  99                 if (ds->ds_ip_addr == ip_addr &&
 100                     ds->ds_port == port) {
 101                         return ds;
 102                 }
 103         }
 104         return NULL;
 105 }
 106
 107 static void
 108 destroy_ds(struct nfs4_pnfs_ds *ds)
 109 {
 110         dprintk("--> %s\n", __func__);
 111         ifdebug(FACILITY)
 112                 print_ds(ds);
 113
 114         if (ds->ds_clp)
 115                 nfs_put_client(ds->ds_clp);
 116         kfree(ds);
 117 }
 118
 119 static void
 120 nfs4_fl_free_deviceid(struct nfs4_file_layout_dsaddr *dsaddr)
 121 {
 122         struct nfs4_pnfs_ds *ds;
 123         int i;
 124
 125         print_deviceid(&dsaddr->deviceid.de_id);
 126
 127         for (i = 0; i < dsaddr->ds_num; i++) {
 128                 ds = dsaddr->ds_list[i];
 129                 if (ds != NULL) {
 130                         if (atomic_dec_and_lock(&ds->ds_count,
 131                                                 &nfs4_ds_cache_lock)) {
 132                                 list_del_init(&ds->ds_node);
 133                                 spin_unlock(&nfs4_ds_cache_lock);
 134                                 destroy_ds(ds);
 135                         }
 136                 }
 137         }
 138         kfree(dsaddr->stripe_indices);
 139         kfree(dsaddr);
 140 }
 141
 142 void
 143 nfs4_fl_free_deviceid_callback(struct pnfs_deviceid_node *device)
 144 {
 145         struct nfs4_file_layout_dsaddr *dsaddr =
 146                 container_of(device, struct nfs4_file_layout_dsaddr, deviceid);
 147
 148         nfs4_fl_free_deviceid(dsaddr);
 149 }
 150
 151 static struct nfs4_pnfs_ds *
 152 nfs4_pnfs_ds_add(struct inode *inode, u32 ip_addr, u32 port)
 153 {
 154         struct nfs4_pnfs_ds *tmp_ds, *ds;
 155
 156         ds = kzalloc(sizeof(*tmp_ds), GFP_KERNEL);
 157         if (!ds)
 158                 goto out;
 159
 160         spin_lock(&nfs4_ds_cache_lock);
 161         tmp_ds = _data_server_lookup_locked(ip_addr, port);
 162         if (tmp_ds == NULL) {
 163                 ds->ds_ip_addr = ip_addr;
 164                 ds->ds_port = port;
 165                 atomic_set(&ds->ds_count, 1);
 166                 INIT_LIST_HEAD(&ds->ds_node);
 167                 ds->ds_clp = NULL;
 168                 list_add(&ds->ds_node, &nfs4_data_server_cache);
 169                 dprintk("%s add new data server ip 0x%x\n", __func__,
 170                         ds->ds_ip_addr);
 171         } else {
 172                 kfree(ds);
 173                 atomic_inc(&tmp_ds->ds_count);
 174                 dprintk("%s data server found ip 0x%x, inc'ed ds_count to %d\n",
 175                         __func__, tmp_ds->ds_ip_addr,
 176                         atomic_read(&tmp_ds->ds_count));
 177                 ds = tmp_ds;
 178         }
 179         spin_unlock(&nfs4_ds_cache_lock);
 180 out:
 181         return ds;
 182 }
 183
 184 /*
 185  * Currently only support ipv4, and one multi-path address.
 186  */
 187 static struct nfs4_pnfs_ds *
 188 decode_and_add_ds(__be32 **pp, struct inode *inode)
 189 {
 190         struct nfs4_pnfs_ds *ds = NULL;
 191         char *buf;
 192         const char *ipend, *pstr;
 193         u32 ip_addr, port;
 194         int nlen, rlen, i;
 195         int tmp[2];
 196         __be32 *r_netid, *r_addr, *p = *pp;
 197
 198         /* r_netid */
 199         nlen = be32_to_cpup(p++);
 200         r_netid = p;
 201         p += XDR_QUADLEN(nlen);
 202
 203         /* r_addr */
 204         rlen = be32_to_cpup(p++);
 205         r_addr = p;
 206         p += XDR_QUADLEN(rlen);
 207         *pp = p;
 208
 209         /* Check that netid is "tcp" */
 210         if (nlen != 3 ||  memcmp((char *)r_netid, "tcp", 3)) {
 211                 dprintk("%s: ERROR: non ipv4 TCP r_netid\n", __func__);
 212                 goto out_err;
 213         }
 214
 215         /* ipv6 length plus port is legal */
 216         if (rlen > INET6_ADDRSTRLEN + 8) {
 217                 dprintk("%s: Invalid address, length %d\n", __func__,
 218                         rlen);
 219                 goto out_err;
 220         }
 221         buf = kmalloc(rlen + 1, GFP_KERNEL);
 222         buf[rlen] = '\0';
 223         memcpy(buf, r_addr, rlen);
 224
 225         /* replace the port dots with dashes for the in4_pton() delimiter*/
 226         for (i = 0; i < 2; i++) {
 227                 char *res = strrchr(buf, '.');
 228                 if (!res) {
 229                         dprintk("%s: Failed finding expected dots in port\n",
 230                                 __func__);
 231                         goto out_free;
 232                 }
 233                 *res = '-';
 234         }
 235
 236         /* Currently only support ipv4 address */
 237         if (in4_pton(buf, rlen, (u8 *)&ip_addr, '-', &ipend) == 0) {
 238                 dprintk("%s: Only ipv4 addresses supported\n", __func__);
 239                 goto out_free;
 240         }
 241
 242         /* port */
 243         pstr = ipend;
 244         sscanf(pstr, "-%d-%d", &tmp[0], &tmp[1]);
 245         port = htons((tmp[0] << 8) | (tmp[1]));
 246
 247         ds = nfs4_pnfs_ds_add(inode, ip_addr, port);
 248         dprintk("%s: Decoded address and port %s\n", __func__, buf);
 249 out_free:
 250         kfree(buf);
 251 out_err:
 252         return ds;
 253 }
 254
 255 /* Decode opaque device data and return the result */
 256 static struct nfs4_file_layout_dsaddr*
 257 decode_device(struct inode *ino, struct pnfs_device *pdev)
 258 {
 259         int i, dummy;
 260         u32 cnt, num;
 261         u8 *indexp;
 262         __be32 *p = (__be32 *)pdev->area, *indicesp;
 263         struct nfs4_file_layout_dsaddr *dsaddr;
 264
 265         /* Get the stripe count (number of stripe index) */
 266         cnt = be32_to_cpup(p++);
 267         dprintk("%s stripe count  %d\n", __func__, cnt);
 268         if (cnt > NFS4_PNFS_MAX_STRIPE_CNT) {
 269                 printk(KERN_WARNING "%s: stripe count %d greater than "
 270                        "supported maximum %d\n", __func__,
 271                         cnt, NFS4_PNFS_MAX_STRIPE_CNT);
 272                 goto out_err;
 273         }
 274
 275         /* Check the multipath list count */
 276         indicesp = p;
 277         p += XDR_QUADLEN(cnt << 2);
 278         num = be32_to_cpup(p++);
 279         dprintk("%s ds_num %u\n", __func__, num);
 280         if (num > NFS4_PNFS_MAX_MULTI_CNT) {
 281                 printk(KERN_WARNING "%s: multipath count %d greater than "
 282                         "supported maximum %d\n", __func__,
 283                         num, NFS4_PNFS_MAX_MULTI_CNT);
 284                 goto out_err;
 285         }
 286         dsaddr = kzalloc(sizeof(*dsaddr) +
 287                         (sizeof(struct nfs4_pnfs_ds *) * (num - 1)),
 288                         GFP_KERNEL);
 289         if (!dsaddr)
 290                 goto out_err;
 291
 292         dsaddr->stripe_indices = kzalloc(sizeof(u8) * cnt, GFP_KERNEL);
 293         if (!dsaddr->stripe_indices)
 294                 goto out_err_free;
 295
 296         dsaddr->stripe_count = cnt;
 297         dsaddr->ds_num = num;
 298
 299         memcpy(&dsaddr->deviceid.de_id, &pdev->dev_id, sizeof(pdev->dev_id));
 300
 301         /* Go back an read stripe indices */
 302         p = indicesp;
 303         indexp = &dsaddr->stripe_indices[0];
 304         for (i = 0; i < dsaddr->stripe_count; i++) {
 305                 *indexp = be32_to_cpup(p++);
 306                 if (*indexp >= num)
 307                         goto out_err_free;
 308                 indexp++;
 309         }
 310         /* Skip already read multipath list count */
 311         p++;
 312
 313         for (i = 0; i < dsaddr->ds_num; i++) {
 314                 int j;
 315
 316                 dummy = be32_to_cpup(p++); /* multipath count */
 317                 if (dummy > 1) {
 318                         printk(KERN_WARNING
 319                                "%s: Multipath count %d not supported, "
 320                                "skipping all greater than 1\n", __func__,
 321                                 dummy);
 322                 }
 323                 for (j = 0; j < dummy; j++) {
 324                         if (j == 0) {
 325                                 dsaddr->ds_list[i] = decode_and_add_ds(&p, ino);
 326                                 if (dsaddr->ds_list[i] == NULL)
 327                                         goto out_err_free;
 328                         } else {
 329                                 u32 len;
 330                                 /* skip extra multipath */
 331                                 len = be32_to_cpup(p++);
 332                                 p += XDR_QUADLEN(len);
 333                                 len = be32_to_cpup(p++);
 334                                 p += XDR_QUADLEN(len);
 335                                 continue;
 336                         }
 337                 }
 338         }
 339         return dsaddr;
 340
 341 out_err_free:
 342         nfs4_fl_free_deviceid(dsaddr);
 343 out_err:
 344         dprintk("%s ERROR: returning NULL\n", __func__);
 345         return NULL;
 346 }
 347
 348 /*
 349  * Decode the opaque device specified in 'dev'
 350  * and add it to the list of available devices.
 351  * If the deviceid is already cached, nfs4_add_deviceid will return
 352  * a pointer to the cached struct and throw away the new.
 353  */
 354 static struct nfs4_file_layout_dsaddr*
 355 decode_and_add_device(struct inode *inode, struct pnfs_device *dev)
 356 {
 357         struct nfs4_file_layout_dsaddr *dsaddr;
 358         struct pnfs_deviceid_node *d;
 359
 360         dsaddr = decode_device(inode, dev);
 361         if (!dsaddr) {
 362                 printk(KERN_WARNING "%s: Could not decode or add device\n",
 363                         __func__);
 364                 return NULL;
 365         }
 366
 367         d = pnfs_add_deviceid(NFS_SERVER(inode)->nfs_client->cl_devid_cache,
 368                               &dsaddr->deviceid);
 369
 370         return container_of(d, struct nfs4_file_layout_dsaddr, deviceid);
 371 }
 372
 373 /*
 374  * Retrieve the information for dev_id, add it to the list
 375  * of available devices, and return it.
 376  */
 377 struct nfs4_file_layout_dsaddr *
 378 get_device_info(struct inode *inode, struct nfs4_deviceid *dev_id)
 379 {
 380         struct pnfs_device *pdev = NULL;
 381         u32 max_resp_sz;
 382         int max_pages;
 383         struct page **pages = NULL;
 384         struct nfs4_file_layout_dsaddr *dsaddr = NULL;
 385         int rc, i;
 386         struct nfs_server *server = NFS_SERVER(inode);
 387
 388         /*
 389          * Use the session max response size as the basis for setting
 390          * GETDEVICEINFO's maxcount
 391          */
 392         max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
 393         max_pages = max_resp_sz >> PAGE_SHIFT;
 394         dprintk("%s inode %p max_resp_sz %u max_pages %d\n",
 395                 __func__, inode, max_resp_sz, max_pages);
 396
 397         pdev = kzalloc(sizeof(struct pnfs_device), GFP_KERNEL);
 398         if (pdev == NULL)
 399                 return NULL;
 400
 401         pages = kzalloc(max_pages * sizeof(struct page *), GFP_KERNEL);
 402         if (pages == NULL) {
 403                 kfree(pdev);
 404                 return NULL;
 405         }
 406         for (i = 0; i < max_pages; i++) {
 407                 pages[i] = alloc_page(GFP_KERNEL);
 408                 if (!pages[i])
 409                         goto out_free;
 410         }
 411
 412         /* set pdev->area */
 413         pdev->area = vmap(pages, max_pages, VM_MAP, PAGE_KERNEL);
 414         if (!pdev->area)
 415                 goto out_free;
 416
 417         memcpy(&pdev->dev_id, dev_id, sizeof(*dev_id));
 418         pdev->layout_type = LAYOUT_NFSV4_1_FILES;
 419         pdev->pages = pages;
 420         pdev->pgbase = 0;
 421         pdev->pglen = PAGE_SIZE * max_pages;
 422         pdev->mincount = 0;
 423
 424         rc = nfs4_proc_getdeviceinfo(server, pdev);
 425         dprintk("%s getdevice info returns %d\n", __func__, rc);
 426         if (rc)
 427                 goto out_free;
 428
 429         /*
 430          * Found new device, need to decode it and then add it to the
 431          * list of known devices for this mountpoint.
 432          */
 433         dsaddr = decode_and_add_device(inode, pdev);
 434 out_free:
 435         if (pdev->area != NULL)
 436                 vunmap(pdev->area);
 437         for (i = 0; i < max_pages; i++)
 438                 __free_page(pages[i]);
 439         kfree(pages);
 440         kfree(pdev);
 441         dprintk("<-- %s dsaddr %p\n", __func__, dsaddr);
 442         return dsaddr;
 443 }
 444
 445 struct nfs4_file_layout_dsaddr *
 446 nfs4_fl_find_get_deviceid(struct nfs_client *clp, struct nfs4_deviceid *id)
 447 {
 448         struct pnfs_deviceid_node *d;
 449
 450         d = pnfs_find_get_deviceid(clp->cl_devid_cache, id);
 451         return (d == NULL) ? NULL :
 452                 container_of(d, struct nfs4_file_layout_dsaddr, deviceid);
 453 }