From 090fd5b10165033d7c30afde0a7e59141d820602 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Sun, 5 Sep 2010 16:17:35 +0900 Subject: [PATCH] nilfs2: get rid of back pointer to writable sb instance Nilfs object holds a back pointer to a writable super block instance in nilfs->ns_writer, and this became eliminable since sb is now made per device and all inodes have a valid pointer to it. This deletes the ns_writer pointer and a reader/writer semaphore protecting it. Signed-off-by: Ryusuke Konishi --- fs/nilfs2/mdt.c | 33 ++------------------------------- fs/nilfs2/recovery.c | 4 ---- fs/nilfs2/segment.c | 4 ---- fs/nilfs2/the_nilfs.c | 1 - fs/nilfs2/the_nilfs.h | 21 --------------------- 5 files changed, 2 insertions(+), 61 deletions(-) diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c index 32695f3c4b9a..0a2ccfc0d6f9 100644 --- a/fs/nilfs2/mdt.c +++ b/fs/nilfs2/mdt.c @@ -78,25 +78,11 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block, struct buffer_head *, void *)) { - struct the_nilfs *nilfs = NILFS_I_NILFS(inode); struct super_block *sb = inode->i_sb; struct nilfs_transaction_info ti; struct buffer_head *bh; int err; - if (!sb) { - /* - * Make sure this function is not called from any - * read-only context. - */ - if (!nilfs->ns_writer) { - WARN_ON(1); - err = -EROFS; - goto out; - } - sb = nilfs->ns_writer->s_super; - } - nilfs_transaction_begin(sb, &ti, 0); err = -ENOMEM; @@ -112,7 +98,7 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block, if (buffer_uptodate(bh)) goto failed_bh; - bh->b_bdev = nilfs->ns_bdev; + bh->b_bdev = sb->s_bdev; err = nilfs_mdt_insert_new_block(inode, block, bh, init_block); if (likely(!err)) { get_bh(bh); @@ -129,7 +115,7 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block, err = nilfs_transaction_commit(sb); else nilfs_transaction_abort(sb); - out: + return err; } @@ -398,8 +384,6 @@ nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc) { struct inode *inode; struct super_block *sb; - struct the_nilfs *nilfs; - struct nilfs_sb_info *writer = NULL; int err = 0; redirty_page_for_writepage(wbc, page); @@ -410,25 +394,12 @@ nilfs_mdt_write_page(struct page *page, struct writeback_control *wbc) return 0; sb = inode->i_sb; - nilfs = NILFS_SB(sb)->s_nilfs; - - if (!sb) { - down_read(&nilfs->ns_writer_sem); - writer = nilfs->ns_writer; - if (!writer) { - up_read(&nilfs->ns_writer_sem); - return -EROFS; - } - sb = writer->s_super; - } if (wbc->sync_mode == WB_SYNC_ALL) err = nilfs_construct_segment(sb); else if (wbc->for_reclaim) nilfs_flush_segment(sb, inode->i_ino); - if (writer) - up_read(&nilfs->ns_writer_sem); return err; } diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c index dcb5a9812c6c..5d2711c28da7 100644 --- a/fs/nilfs2/recovery.c +++ b/fs/nilfs2/recovery.c @@ -440,7 +440,6 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, segnum[2] = ri->ri_segnum; segnum[3] = ri->ri_nextnum; - nilfs_attach_writer(nilfs, sbi); /* * Releasing the next segment of the latest super root. * The next segment is invalidated by this recovery. @@ -480,7 +479,6 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs, failed: /* No need to recover sufile because it will be destroyed on error */ - nilfs_detach_writer(nilfs, sbi); return err; } @@ -599,7 +597,6 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs, }; int state = RF_INIT_ST; - nilfs_attach_writer(nilfs, sbi); pseg_start = ri->ri_lsegs_start; seg_seq = ri->ri_lsegs_start_seq; segnum = nilfs_get_segnum_of_block(nilfs, pseg_start); @@ -690,7 +687,6 @@ static int nilfs_do_roll_forward(struct the_nilfs *nilfs, out: brelse(bh_sum); dispose_recovery_list(&dsync_blocks); - nilfs_detach_writer(nilfs, sbi); return err; confused: diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c index b0c5e08d06c8..56350bf1f79f 100644 --- a/fs/nilfs2/segment.c +++ b/fs/nilfs2/segment.c @@ -2799,7 +2799,6 @@ static void nilfs_segctor_destroy(struct nilfs_sc_info *sci) int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi, struct nilfs_root *root) { - struct the_nilfs *nilfs = sbi->s_nilfs; int err; if (NILFS_SC(sbi)) { @@ -2815,10 +2814,8 @@ int nilfs_attach_segment_constructor(struct nilfs_sb_info *sbi, if (!sbi->s_sc_info) return -ENOMEM; - nilfs_attach_writer(nilfs, sbi); err = nilfs_segctor_start_thread(NILFS_SC(sbi)); if (err) { - nilfs_detach_writer(nilfs, sbi); kfree(sbi->s_sc_info); sbi->s_sc_info = NULL; } @@ -2855,5 +2852,4 @@ void nilfs_detach_segment_constructor(struct nilfs_sb_info *sbi) up_write(&nilfs->ns_segctor_sem); nilfs_dispose_list(sbi, &garbage_list, 1); - nilfs_detach_writer(nilfs, sbi); } diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 4cc705a1d135..a94aa57c4bd9 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -75,7 +75,6 @@ struct the_nilfs *alloc_nilfs(struct block_device *bdev) nilfs->ns_bdev = bdev; atomic_set(&nilfs->ns_ndirtyblks, 0); init_rwsem(&nilfs->ns_sem); - init_rwsem(&nilfs->ns_writer_sem); INIT_LIST_HEAD(&nilfs->ns_gc_inodes); spin_lock_init(&nilfs->ns_last_segment_lock); nilfs->ns_cptree = RB_ROOT; diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index cae56f338b64..bbbc1c748aac 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -48,9 +48,7 @@ enum { * @ns_flags: flags * @ns_bdev: block device * @ns_bdi: backing dev info - * @ns_writer: back pointer to writable nilfs_sb_info * @ns_sem: semaphore for shared states - * @ns_writer_sem: semaphore protecting ns_writer attach/detach * @ns_sbh: buffer heads of on-disk super blocks * @ns_sbp: pointers to super block data * @ns_sbwtime: previous write time of super block @@ -93,9 +91,7 @@ struct the_nilfs { struct block_device *ns_bdev; struct backing_dev_info *ns_bdi; - struct nilfs_sb_info *ns_writer; struct rw_semaphore ns_sem; - struct rw_semaphore ns_writer_sem; /* * used for @@ -252,23 +248,6 @@ static inline void nilfs_get_root(struct nilfs_root *root) atomic_inc(&root->count); } -static inline void -nilfs_attach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) -{ - down_write(&nilfs->ns_writer_sem); - nilfs->ns_writer = sbi; - up_write(&nilfs->ns_writer_sem); -} - -static inline void -nilfs_detach_writer(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) -{ - down_write(&nilfs->ns_writer_sem); - if (sbi == nilfs->ns_writer) - nilfs->ns_writer = NULL; - up_write(&nilfs->ns_writer_sem); -} - static inline int nilfs_valid_fs(struct the_nilfs *nilfs) { unsigned valid_fs; -- 2.11.4.GIT