nfs4renewd.c 4.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157
  1. /*
  2. * fs/nfs/nfs4renewd.c
  3. *
  4. * Copyright (c) 2002 The Regents of the University of Michigan.
  5. * All rights reserved.
  6. *
  7. * Kendrick Smith <kmsmith@umich.edu>
  8. *
  9. * Redistribution and use in source and binary forms, with or without
  10. * modification, are permitted provided that the following conditions
  11. * are met:
  12. *
  13. * 1. Redistributions of source code must retain the above copyright
  14. * notice, this list of conditions and the following disclaimer.
  15. * 2. Redistributions in binary form must reproduce the above copyright
  16. * notice, this list of conditions and the following disclaimer in the
  17. * documentation and/or other materials provided with the distribution.
  18. * 3. Neither the name of the University nor the names of its
  19. * contributors may be used to endorse or promote products derived
  20. * from this software without specific prior written permission.
  21. *
  22. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  23. * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24. * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25. * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27. * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28. * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  29. * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30. * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  31. * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  32. * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33. *
  34. * Implementation of the NFSv4 "renew daemon", which wakes up periodically to
  35. * send a RENEW, to keep state alive on the server. The daemon is implemented
  36. * as an rpc_task, not a real kernel thread, so it always runs in rpciod's
  37. * context. There is one renewd per nfs_server.
  38. *
  39. */
  40. #include <linux/mm.h>
  41. #include <linux/pagemap.h>
  42. #include <linux/sunrpc/sched.h>
  43. #include <linux/sunrpc/clnt.h>
  44. #include <linux/nfs.h>
  45. #include <linux/nfs4.h>
  46. #include <linux/nfs_fs.h>
  47. #include "nfs4_fs.h"
  48. #include "delegation.h"
  49. #define NFSDBG_FACILITY NFSDBG_STATE
  50. void
  51. nfs4_renew_state(struct work_struct *work)
  52. {
  53. const struct nfs4_state_maintenance_ops *ops;
  54. struct nfs_client *clp =
  55. container_of(work, struct nfs_client, cl_renewd.work);
  56. const struct cred *cred;
  57. long lease;
  58. unsigned long last, now;
  59. unsigned renew_flags = 0;
  60. ops = clp->cl_mvops->state_renewal_ops;
  61. dprintk("%s: start\n", __func__);
  62. if (test_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state))
  63. goto out;
  64. lease = clp->cl_lease_time;
  65. last = clp->cl_last_renewal;
  66. now = jiffies;
  67. /* Are we close to a lease timeout? */
  68. if (time_after(now, last + lease/3))
  69. renew_flags |= NFS4_RENEW_TIMEOUT;
  70. if (nfs_delegations_present(clp))
  71. renew_flags |= NFS4_RENEW_DELEGATION_CB;
  72. if (renew_flags != 0) {
  73. cred = ops->get_state_renewal_cred(clp);
  74. if (cred == NULL) {
  75. if (!(renew_flags & NFS4_RENEW_DELEGATION_CB)) {
  76. set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
  77. goto out;
  78. }
  79. nfs_expire_all_delegations(clp);
  80. } else {
  81. int ret;
  82. /* Queue an asynchronous RENEW. */
  83. ret = ops->sched_state_renewal(clp, cred, renew_flags);
  84. put_cred(cred);
  85. switch (ret) {
  86. default:
  87. goto out_exp;
  88. case -EAGAIN:
  89. case -ENOMEM:
  90. break;
  91. }
  92. }
  93. } else {
  94. dprintk("%s: failed to call renewd. Reason: lease not expired \n",
  95. __func__);
  96. }
  97. nfs4_schedule_state_renewal(clp);
  98. out_exp:
  99. nfs_expire_unreferenced_delegations(clp);
  100. out:
  101. dprintk("%s: done\n", __func__);
  102. }
  103. void
  104. nfs4_schedule_state_renewal(struct nfs_client *clp)
  105. {
  106. long timeout;
  107. spin_lock(&clp->cl_lock);
  108. timeout = (2 * clp->cl_lease_time) / 3 + (long)clp->cl_last_renewal
  109. - (long)jiffies;
  110. if (timeout < 5 * HZ)
  111. timeout = 5 * HZ;
  112. dprintk("%s: requeueing work. Lease period = %ld\n",
  113. __func__, (timeout + HZ - 1) / HZ);
  114. mod_delayed_work(system_wq, &clp->cl_renewd, timeout);
  115. set_bit(NFS_CS_RENEWD, &clp->cl_res_state);
  116. spin_unlock(&clp->cl_lock);
  117. }
  118. void
  119. nfs4_kill_renewd(struct nfs_client *clp)
  120. {
  121. cancel_delayed_work_sync(&clp->cl_renewd);
  122. }
  123. /**
  124. * nfs4_set_lease_period - Sets the lease period on a nfs_client
  125. *
  126. * @clp: pointer to nfs_client
  127. * @lease: new value for lease period
  128. */
  129. void nfs4_set_lease_period(struct nfs_client *clp,
  130. unsigned long lease)
  131. {
  132. spin_lock(&clp->cl_lock);
  133. clp->cl_lease_time = lease;
  134. spin_unlock(&clp->cl_lock);
  135. /* Cap maximum reconnect timeout at 1/2 lease period */
  136. rpc_set_connect_timeout(clp->cl_rpcclient, lease, lease >> 1);
  137. }
  138. /*
  139. * Local variables:
  140. * c-basic-offset: 8
  141. * End:
  142. */