cache.c 1.8 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /* AFS caching stuff
  3. *
  4. * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
  5. * Written by David Howells (dhowells@redhat.com)
  6. */
  7. #include <linux/sched.h>
  8. #include "internal.h"
  9. static enum fscache_checkaux afs_vnode_cache_check_aux(void *cookie_netfs_data,
  10. const void *buffer,
  11. uint16_t buflen,
  12. loff_t object_size);
  13. struct fscache_netfs afs_cache_netfs = {
  14. .name = "afs",
  15. .version = 2,
  16. };
  17. struct fscache_cookie_def afs_cell_cache_index_def = {
  18. .name = "AFS.cell",
  19. .type = FSCACHE_COOKIE_TYPE_INDEX,
  20. };
  21. struct fscache_cookie_def afs_volume_cache_index_def = {
  22. .name = "AFS.volume",
  23. .type = FSCACHE_COOKIE_TYPE_INDEX,
  24. };
  25. struct fscache_cookie_def afs_vnode_cache_index_def = {
  26. .name = "AFS.vnode",
  27. .type = FSCACHE_COOKIE_TYPE_DATAFILE,
  28. .check_aux = afs_vnode_cache_check_aux,
  29. };
  30. /*
  31. * check that the auxiliary data indicates that the entry is still valid
  32. */
  33. static enum fscache_checkaux afs_vnode_cache_check_aux(void *cookie_netfs_data,
  34. const void *buffer,
  35. uint16_t buflen,
  36. loff_t object_size)
  37. {
  38. struct afs_vnode *vnode = cookie_netfs_data;
  39. struct afs_vnode_cache_aux aux;
  40. _enter("{%llx,%x,%llx},%p,%u",
  41. vnode->fid.vnode, vnode->fid.unique, vnode->status.data_version,
  42. buffer, buflen);
  43. memcpy(&aux, buffer, sizeof(aux));
  44. /* check the size of the data is what we're expecting */
  45. if (buflen != sizeof(aux)) {
  46. _leave(" = OBSOLETE [len %hx != %zx]", buflen, sizeof(aux));
  47. return FSCACHE_CHECKAUX_OBSOLETE;
  48. }
  49. if (vnode->status.data_version != aux.data_version) {
  50. _leave(" = OBSOLETE [vers %llx != %llx]",
  51. aux.data_version, vnode->status.data_version);
  52. return FSCACHE_CHECKAUX_OBSOLETE;
  53. }
  54. _leave(" = SUCCESS");
  55. return FSCACHE_CHECKAUX_OKAY;
  56. }