nilfs2: insert checkpoint number in segment summary header

[safe/jmp/linux-2.6] / fs / nilfs2 / the_nilfs.c

diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 6241e17..33871f7 100644 (file)
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -386,7 +386,7 @@ static int nilfs_store_disk_layout(struct the_nilfs *nilfs,
 
        nilfs->ns_blocks_per_segment = le32_to_cpu(sbp->s_blocks_per_segment);
        if (nilfs->ns_blocks_per_segment < NILFS_SEG_MIN_BLOCKS) {
-               printk(KERN_ERR "NILFS: too short segment. \n");
+               printk(KERN_ERR "NILFS: too short segment.\n");
                return -EINVAL;
        }
 
@@ -646,6 +646,44 @@ int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data)
        goto out;
 }
 
+int nilfs_discard_segments(struct the_nilfs *nilfs, __u64 *segnump,
+                           size_t nsegs)
+{
+       sector_t seg_start, seg_end;
+       sector_t start = 0, nblocks = 0;
+       unsigned int sects_per_block;
+       __u64 *sn;
+       int ret = 0;
+
+       sects_per_block = (1 << nilfs->ns_blocksize_bits) /
+               bdev_logical_block_size(nilfs->ns_bdev);
+       for (sn = segnump; sn < segnump + nsegs; sn++) {
+               nilfs_get_segment_range(nilfs, *sn, &seg_start, &seg_end);
+
+               if (!nblocks) {
+                       start = seg_start;
+                       nblocks = seg_end - seg_start + 1;
+               } else if (start + nblocks == seg_start) {
+                       nblocks += seg_end - seg_start + 1;
+               } else {
+                       ret = blkdev_issue_discard(nilfs->ns_bdev,
+                                                  start * sects_per_block,
+                                                  nblocks * sects_per_block,
+                                                  GFP_NOFS,
+                                                  DISCARD_FL_BARRIER);
+                       if (ret < 0)
+                               return ret;
+                       nblocks = 0;
+               }
+       }
+       if (nblocks)
+               ret = blkdev_issue_discard(nilfs->ns_bdev,
+                                          start * sects_per_block,
+                                          nblocks * sects_per_block,
+                                          GFP_NOFS, DISCARD_FL_BARRIER);
+       return ret;
+}
+
 int nilfs_count_free_blocks(struct the_nilfs *nilfs, sector_t *nblocks)
 {
        struct inode *dat = nilfs_dat_inode(nilfs);