From 715189d836ab276b3d0fc114681f12b423686ffa Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:28:44 +0300 Subject: hfs: push lock_super down HFS uses 'lock_super()'/'unlock_super()' around 'hfs_mdb_commit()' in order to serialize MDB (Master Directory Block) changes. Push it down to 'hfs_mdb_commit()' in order to simplify the code a bit. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfs/super.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'fs/hfs/super.c') diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 7b4c537d6e13..f7c06bbf33bc 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -50,21 +50,17 @@ MODULE_LICENSE("GPL"); */ static void hfs_write_super(struct super_block *sb) { - lock_super(sb); sb->s_dirt = 0; /* sync everything to the buffers */ if (!(sb->s_flags & MS_RDONLY)) hfs_mdb_commit(sb); - unlock_super(sb); } static int hfs_sync_fs(struct super_block *sb, int wait) { - lock_super(sb); hfs_mdb_commit(sb); sb->s_dirt = 0; - unlock_super(sb); return 0; } -- cgit v1.2.3 From a3742d4828caeffab4cb075b562a4ed92d3e74d6 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:28:46 +0300 Subject: hfs: remove extra mdb write on unmount HFS calls 'hfs_write_super()' from 'hfs_put_super()' in order to write the MDB to the media. However, it is not needed because VFS calls '->sync_fs()' before calling '->put_super()' - so by the time we are in 'hfs_write_super()', the MDB is already synchronized. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfs/super.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'fs/hfs/super.c') diff --git a/fs/hfs/super.c b/fs/hfs/super.c index f7c06bbf33bc..47e4119a0650 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -74,8 +74,6 @@ static int hfs_sync_fs(struct super_block *sb, int wait) */ static void hfs_put_super(struct super_block *sb) { - if (sb->s_dirt) - hfs_write_super(sb); hfs_mdb_close(sb); /* release the MDB's resources */ hfs_mdb_put(sb); -- cgit v1.2.3 From 4527440d5db8ff27ae8801de3f819843a1e6c6f6 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:28:47 +0300 Subject: hfs: simplify a bit checking for R/O We have the following pattern in 2 places in HFS if (!RDONLY) hfs_mdb_commit(); This patch pushes the RDONLY check down to 'hfs_mdb_commit()'. This will make the following patches a bit simpler. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfs/super.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/hfs/super.c') diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 47e4119a0650..0730135b771e 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -53,8 +53,7 @@ static void hfs_write_super(struct super_block *sb) sb->s_dirt = 0; /* sync everything to the buffers */ - if (!(sb->s_flags & MS_RDONLY)) - hfs_mdb_commit(sb); + hfs_mdb_commit(sb); } static int hfs_sync_fs(struct super_block *sb, int wait) -- cgit v1.2.3 From b16ca626358cbf056b752eab63ba8f20087afeaf Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:28:48 +0300 Subject: hfs: introduce VFS superblock object back-reference Add an 'sb' VFS superblock back-reference to the 'struct hfs_sb_info' data structure - we will need to find the VFS superblock from a 'struct hfs_sb_info' object in the next patch, so this change is jut a preparation. Remove few useless newlines while on it. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfs/super.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/hfs/super.c') diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 0730135b771e..99c6239bc3a1 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -380,6 +380,7 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent) if (!sbi) return -ENOMEM; + sbi->sb = sb; sb->s_fs_info = sbi; res = -EINVAL; -- cgit v1.2.3 From 5687b5780e90278a62d4cd916a3632087066f59d Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:28:49 +0300 Subject: hfs: get rid of hfs_sync_super This patch makes hfs stop using the VFS '->write_super()' method along with the 's_dirt' superblock flag, because they are on their way out. The whole "superblock write-out" VFS infrastructure is served by the 'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and writes out all dirty superblocks using the '->write_super()' call-back. But the problem with this thread is that it wastes power by waking up the system every 5 seconds, even if there are no diry superblocks, or there are no client file-systems which would need this (e.g., btrfs does not use '->write_super()'). So we want to kill it completely and thus, we need to make file-systems to stop using the '->write_super()' VFS service, and then remove it together with the kernel thread. Tested using fsstress from the LTP project. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfs/super.c | 65 +++++++++++++++++++++++++++++++--------------------------- 1 file changed, 35 insertions(+), 30 deletions(-) (limited to 'fs/hfs/super.c') diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 99c6239bc3a1..4eb873e0c07b 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -29,38 +29,9 @@ static struct kmem_cache *hfs_inode_cachep; MODULE_LICENSE("GPL"); -/* - * hfs_write_super() - * - * Description: - * This function is called by the VFS only. When the filesystem - * is mounted r/w it updates the MDB on disk. - * Input Variable(s): - * struct super_block *sb: Pointer to the hfs superblock - * Output Variable(s): - * NONE - * Returns: - * void - * Preconditions: - * 'sb' points to a "valid" (struct super_block). - * Postconditions: - * The MDB is marked 'unsuccessfully unmounted' by clearing bit 8 of drAtrb - * (hfs_put_super() must set this flag!). Some MDB fields are updated - * and the MDB buffer is written to disk by calling hfs_mdb_commit(). - */ -static void hfs_write_super(struct super_block *sb) -{ - sb->s_dirt = 0; - - /* sync everything to the buffers */ - hfs_mdb_commit(sb); -} - static int hfs_sync_fs(struct super_block *sb, int wait) { hfs_mdb_commit(sb); - sb->s_dirt = 0; - return 0; } @@ -73,11 +44,44 @@ static int hfs_sync_fs(struct super_block *sb, int wait) */ static void hfs_put_super(struct super_block *sb) { + cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work); hfs_mdb_close(sb); /* release the MDB's resources */ hfs_mdb_put(sb); } +static void flush_mdb(struct work_struct *work) +{ + struct hfs_sb_info *sbi; + struct super_block *sb; + + sbi = container_of(work, struct hfs_sb_info, mdb_work.work); + sb = sbi->sb; + + spin_lock(&sbi->work_lock); + sbi->work_queued = 0; + spin_unlock(&sbi->work_lock); + + hfs_mdb_commit(sb); +} + +void hfs_mark_mdb_dirty(struct super_block *sb) +{ + struct hfs_sb_info *sbi = HFS_SB(sb); + unsigned long delay; + + if (sb->s_flags & MS_RDONLY) + return; + + spin_lock(&sbi->work_lock); + if (!sbi->work_queued) { + delay = msecs_to_jiffies(dirty_writeback_interval * 10); + queue_delayed_work(system_long_wq, &sbi->mdb_work, delay); + sbi->work_queued = 1; + } + spin_unlock(&sbi->work_lock); +} + /* * hfs_statfs() * @@ -177,7 +181,6 @@ static const struct super_operations hfs_super_operations = { .write_inode = hfs_write_inode, .evict_inode = hfs_evict_inode, .put_super = hfs_put_super, - .write_super = hfs_write_super, .sync_fs = hfs_sync_fs, .statfs = hfs_statfs, .remount_fs = hfs_remount, @@ -382,6 +385,8 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent) sbi->sb = sb; sb->s_fs_info = sbi; + spin_lock_init(&sbi->work_lock); + INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); res = -EINVAL; if (!parse_options((char *)data, sbi)) { -- cgit v1.2.3