ldiskfs/kernel_patches/patches/sles11sp2/ext4-map_inode_page-3.0.patch

   1 ---
   2  fs/ext4/ext4.h  |    3 ++
   3  fs/ext4/inode.c |   68 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   4  2 files changed, 71 insertions(+)
   5
   6 --- a/fs/ext4/ext4.h
   7 +++ b/fs/ext4/ext4.h
   8 @@ -1838,6 +1838,9 @@ extern int ext4_page_mkwrite(struct vm_a
   9  extern qsize_t *ext4_get_reserved_space(struct inode *inode);
  10  extern void ext4_da_update_reserve_space(struct inode *inode,
  11                                         int used, int quota_claim);
  12 +extern int ext4_map_inode_page(struct inode *inode, struct page *page,
  13 +                              unsigned long *blocks, int created);
  14 +
  15  /* ioctl.c */
  16  extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
  17  extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
  18 --- a/fs/ext4/inode.c
  19 +++ b/fs/ext4/inode.c
  20 @@ -5968,3 +5968,65 @@ out_unlock:
  21         up_read(&inode->i_alloc_sem);
  22         return ret;
  23  }
  24 +
  25 +int ext4_map_inode_page(struct inode *inode, struct page *page,
  26 +                       unsigned long *blocks, int create)
  27 +{
  28 +       unsigned int blocksize, blocks_per_page;
  29 +       unsigned long iblock;
  30 +       struct ext4_map_blocks map;
  31 +       void *handle;
  32 +       int i, rc = 0, failed = 0, needed_blocks;
  33 +
  34 +       blocksize = inode->i_sb->s_blocksize;
  35 +       blocks_per_page = PAGE_SIZE >> inode->i_sb->s_blocksize_bits;
  36 +       iblock = page->index * blocks_per_page;
  37 +
  38 +       for (i = 0; i < blocks_per_page; i++, iblock++) {
  39 +               blocks[i] = ext4_bmap(inode->i_mapping, iblock);
  40 +               if (blocks[i] == 0) {
  41 +                       failed++;
  42 +               }
  43 +       }
  44 +
  45 +       if (failed == 0 || create == 0)
  46 +               return 0;
  47 +
  48 +       needed_blocks = ext4_writepage_trans_blocks(inode);
  49 +       handle = ext4_journal_start(inode, needed_blocks);
  50 +       if (IS_ERR(handle))
  51 +               return PTR_ERR(handle);
  52 +
  53 +       iblock = page->index * blocks_per_page;
  54 +       for (i = 0; i < blocks_per_page; i++, iblock++) {
  55 +               if (blocks[i] != 0)
  56 +                       continue;
  57 +
  58 +               map.m_lblk = iblock;
  59 +               map.m_len = 1;
  60 +               map.m_flags = 0;
  61 +               rc = ext4_ind_map_blocks(handle, inode, &map,
  62 +                                        EXT4_GET_BLOCKS_CREATE);
  63 +               if (rc < 0) {
  64 +                       printk(KERN_INFO "ext4_map_inode_page: error reading "
  65 +                                       "block %ld\n", iblock);
  66 +                       goto out;
  67 +               } else {
  68 +                       if (rc > 1)
  69 +                               WARN_ON(1);
  70 +                       rc = 0;
  71 +               }
  72 +               /* Unmap any metadata buffers from the block mapping, to avoid
  73 +                * data corruption due to direct-write from Lustre being
  74 +                * clobbered by a later flush of the blockdev metadata buffer.*/
  75 +               if (map.m_flags & EXT4_MAP_NEW)
  76 +                       unmap_underlying_metadata(inode->i_sb->s_bdev,
  77 +                                       map.m_pblk);
  78 +               blocks[i] = map.m_pblk;
  79 +       }
  80 +
  81 +out:
  82 +       ext4_journal_stop(handle);
  83 +       return rc;
  84 +}
  85 +EXPORT_SYMBOL(ext4_map_inode_page);