Hi, Konishi-san, thank you for the comment.
I revised the patch so as to remove the nilfs->ns_current reference. I introduce new variable "ret" instead of reuseing "err" in nilfs_clean_segments so that error of discard request won't stop GC process. 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]> Signed-off-by: Jiro SEKIBA <[email protected]> --- Documentation/filesystems/nilfs2.txt | 3 ++ fs/nilfs2/segment.c | 10 +++++++++ fs/nilfs2/super.c | 8 ++++++- fs/nilfs2/the_nilfs.c | 38 ++++++++++++++++++++++++++++++++++ fs/nilfs2/the_nilfs.h | 1 + include/linux/nilfs2_fs.h | 1 + 6 files changed, 60 insertions(+), 1 deletions(-) diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt index 839efd8..cf6d0d8 100644 --- a/Documentation/filesystems/nilfs2.txt +++ b/Documentation/filesystems/nilfs2.txt @@ -74,6 +74,9 @@ norecovery Disable recovery of the filesystem on mount. This disables every write access on the device for read-only mounts or snapshots. This option will fail for r/w mounts on an unclean volume. +discard Issue discard/TRIM commands to the underlying block + device when blocks are freed. This is useful for SSD + devices and sparse/thinly-provisioned LUNs. NILFS2 usage ============ diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index 17584c5..9eae057 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2560,6 +2560,16 @@ int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv, set_current_state(TASK_INTERRUPTIBLE); schedule_timeout(sci->sc_interval); } + if (nilfs_test_opt(sbi, DISCARD)) { + int ret = nilfs_discard_segments(nilfs, sci->sc_freesegs, + sci->sc_nfreesegs); + if (ret) { + printk(KERN_WARNING + "NILFS warning: error %d on discard request, " + "turning discards off for the device\n", ret); + nilfs_clear_opt(sbi, DISCARD); + } + } out_unlock: sci->sc_freesegs = NULL; diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 8173fae..3f88401 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -481,6 +481,8 @@ static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs) seq_printf(seq, ",order=strict"); if (nilfs_test_opt(sbi, NORECOVERY)) seq_printf(seq, ",norecovery"); + if (nilfs_test_opt(sbi, DISCARD)) + seq_printf(seq, ",discard"); return 0; } @@ -550,7 +552,7 @@ static const struct export_operations nilfs_export_ops = { enum { Opt_err_cont, Opt_err_panic, Opt_err_ro, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery, - Opt_err, + Opt_discard, Opt_err, }; static match_table_t tokens = { @@ -561,6 +563,7 @@ static match_table_t tokens = { {Opt_snapshot, "cp=%u"}, {Opt_order, "order=%s"}, {Opt_norecovery, "norecovery"}, + {Opt_discard, "discard"}, {Opt_err, NULL} }; @@ -614,6 +617,9 @@ static int parse_options(char *options, struct super_block *sb) case Opt_norecovery: nilfs_set_opt(sbi, NORECOVERY); break; + case Opt_discard: + nilfs_set_opt(sbi, DISCARD); + break; default: printk(KERN_ERR "NILFS: Unrecognized mount option \"%s\"\n", p); diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 6241e17..92733d5 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -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); diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index 589786e..fd057f8 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -221,6 +221,7 @@ 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 *); +int 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); diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h index 3fe02cf..640702e 100644 --- a/include/linux/nilfs2_fs.h +++ b/include/linux/nilfs2_fs.h @@ -153,6 +153,7 @@ struct nilfs_super_root { semantics also for data */ #define NILFS_MOUNT_NORECOVERY 0x4000 /* Disable write access during mount-time recovery */ +#define NILFS_MOUNT_DISCARD 0x8000 /* Issue DISCARD requests */ /** -- 1.5.6.5 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
