This adds a function to send discard requests for given array of
segment numbers, and calls the function when garbage collection
succeeded.

Signed-off-by: Ryusuke Konishi <[email protected]>
---
 fs/nilfs2/segment.c   |    3 +++
 fs/nilfs2/the_nilfs.c |   44 ++++++++++++++++++++++++++++++++++++++++++++
 fs/nilfs2/the_nilfs.h |    3 +++
 3 files changed, 50 insertions(+), 0 deletions(-)

diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index aa97754..23e6014 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2569,6 +2569,9 @@ int nilfs_clean_segments(struct super_block *sb, struct 
nilfs_argv *argv,
                set_current_state(TASK_INTERRUPTIBLE);
                schedule_timeout(sci->sc_interval);
        }
+       if (nilfs_discard(nilfs))
+               nilfs_discard_segments(nilfs, sci->sc_freesegs,
+                                      sci->sc_nfreesegs);
 
  out_unlock:
        sci->sc_freesegs = NULL;
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index a4a692c..07352b3 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -634,6 +634,50 @@ int init_nilfs(struct the_nilfs *nilfs, struct 
nilfs_sb_info *sbi, char *data)
        goto out;
 }
 
+void 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_hardsect_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);
+                       if (ret < 0)
+                               goto failed;
+                       nblocks = 0;
+               }
+       }
+       if (nblocks) {
+               ret = blkdev_issue_discard(nilfs->ns_bdev,
+                                          start * sects_per_block,
+                                          nblocks * sects_per_block,
+                                          GFP_NOFS);
+               if (ret < 0)
+                       goto failed;
+       }
+       return;
+ failed:
+       printk(KERN_WARNING "NILFS warning: error %d on discard request, "
+              "turning discards off for the device\n", ret);
+       clear_nilfs_discard(nilfs);
+}
+
 int nilfs_count_free_blocks(struct the_nilfs *nilfs, sector_t *nblocks)
 {
        struct inode *dat = nilfs_dat_inode(nilfs);
diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h
index 53fb1e6..6a1e40e 100644
--- a/fs/nilfs2/the_nilfs.h
+++ b/fs/nilfs2/the_nilfs.h
@@ -37,6 +37,7 @@ enum {
        THE_NILFS_LOADED,       /* Roll-back/roll-forward has done and
                                   the latest checkpoint was loaded */
        THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */
+       THE_NILFS_DISCARD,      /* discard operation on/off */
 };
 
 /**
@@ -195,6 +196,7 @@ static inline int nilfs_##name(struct the_nilfs *nilfs)     
                \
 THE_NILFS_FNS(INIT, init)
 THE_NILFS_FNS(LOADED, loaded)
 THE_NILFS_FNS(DISCONTINUED, discontinued)
+THE_NILFS_FNS(DISCARD, discard)
 
 /* Minimum interval of periodical update of superblocks (in seconds) */
 #define NILFS_SB_FREQ          10
@@ -205,6 +207,7 @@ struct the_nilfs *find_or_create_nilfs(struct block_device 
*);
 void put_nilfs(struct the_nilfs *);
 int init_nilfs(struct the_nilfs *, struct nilfs_sb_info *, char *);
 int load_nilfs(struct the_nilfs *, struct nilfs_sb_info *);
+void nilfs_discard_segments(struct the_nilfs *, __u64 *, size_t);
 int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
 struct nilfs_sb_info *nilfs_find_sbinfo(struct the_nilfs *, int, __u64);
 int nilfs_checkpoint_is_mounted(struct the_nilfs *, __u64, int);
-- 
1.6.2

_______________________________________________
users mailing list
[email protected]
https://www.nilfs.org/mailman/listinfo/users

Reply via email to