vxfs_immed.c 1.2 KB

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  1. // SPDX-License-Identifier: GPL-2.0-only
  2. /*
  3. * Copyright (c) 2000-2001 Christoph Hellwig.
  4. */
  5. /*
  6. * Veritas filesystem driver - support for 'immed' inodes.
  7. */
  8. #include <linux/fs.h>
  9. #include <linux/pagemap.h>
  10. #include "vxfs.h"
  11. #include "vxfs_extern.h"
  12. #include "vxfs_inode.h"
  13. /**
  14. * vxfs_immed_read_folio - read part of an immed inode into pagecache
  15. * @file: file context (unused)
  16. * @folio: folio to fill in.
  17. *
  18. * Description:
  19. * vxfs_immed_read_folio reads a part of the immed area of the
  20. * file that hosts @folio into the pagecache.
  21. *
  22. * Returns:
  23. * Zero on success, else a negative error code.
  24. *
  25. * Locking status:
  26. * @folio is locked and will be unlocked.
  27. */
  28. static int vxfs_immed_read_folio(struct file *fp, struct folio *folio)
  29. {
  30. struct vxfs_inode_info *vip = VXFS_INO(folio->mapping->host);
  31. void *src = vip->vii_immed.vi_immed + folio_pos(folio);
  32. unsigned long i;
  33. for (i = 0; i < folio_nr_pages(folio); i++) {
  34. memcpy_to_page(folio_page(folio, i), 0, src, PAGE_SIZE);
  35. src += PAGE_SIZE;
  36. }
  37. folio_mark_uptodate(folio);
  38. folio_unlock(folio);
  39. return 0;
  40. }
  41. /*
  42. * Address space operations for immed files and directories.
  43. */
  44. const struct address_space_operations vxfs_immed_aops = {
  45. .read_folio = vxfs_immed_read_folio,
  46. };