From 30687e0a47e89f56489ab73965ee88231e611986 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 3 Oct 2013 12:25:10 -0400 Subject: [PATCH] hpfs: make freeing sbi and codetables rcu-delayed makes ->d_hash() and ->d_compare() safety in RCU mode independent from vfsmount_lock Signed-off-by: Al Viro --- fs/hpfs/hpfs_fn.h | 1 + fs/hpfs/super.c | 28 ++++++++++++++-------------- 2 files changed, 15 insertions(+), 14 deletions(-) diff --git a/fs/hpfs/hpfs_fn.h b/fs/hpfs/hpfs_fn.h index 1b398636e99..6797bf80f6e 100644 --- a/fs/hpfs/hpfs_fn.h +++ b/fs/hpfs/hpfs_fn.h @@ -80,6 +80,7 @@ struct hpfs_sb_info { unsigned sb_c_bitmap; /* current bitmap */ unsigned sb_max_fwd_alloc; /* max forwad allocation */ int sb_timeshift; + struct rcu_head rcu; }; /* Four 512-byte buffers and the 2k block obtained by concatenating them */ diff --git a/fs/hpfs/super.c b/fs/hpfs/super.c index 4334cda8dba..b8d01ef6f53 100644 --- a/fs/hpfs/super.c +++ b/fs/hpfs/super.c @@ -101,18 +101,24 @@ int hpfs_stop_cycles(struct super_block *s, int key, int *c1, int *c2, return 0; } -static void hpfs_put_super(struct super_block *s) +static void free_sbi(struct hpfs_sb_info *sbi) { - struct hpfs_sb_info *sbi = hpfs_sb(s); + kfree(sbi->sb_cp_table); + kfree(sbi->sb_bmp_dir); + kfree(sbi); +} +static void lazy_free_sbi(struct rcu_head *rcu) +{ + free_sbi(container_of(rcu, struct hpfs_sb_info, rcu)); +} + +static void hpfs_put_super(struct super_block *s) +{ hpfs_lock(s); unmark_dirty(s); hpfs_unlock(s); - - kfree(sbi->sb_cp_table); - kfree(sbi->sb_bmp_dir); - s->s_fs_info = NULL; - kfree(sbi); + call_rcu(&hpfs_sb(s)->rcu, lazy_free_sbi); } unsigned hpfs_count_one_bitmap(struct super_block *s, secno secno) @@ -485,9 +491,6 @@ static int hpfs_fill_super(struct super_block *s, void *options, int silent) } s->s_fs_info = sbi; - sbi->sb_bmp_dir = NULL; - sbi->sb_cp_table = NULL; - mutex_init(&sbi->hpfs_mutex); hpfs_lock(s); @@ -679,10 +682,7 @@ bail2: brelse(bh0); bail1: bail0: hpfs_unlock(s); - kfree(sbi->sb_bmp_dir); - kfree(sbi->sb_cp_table); - s->s_fs_info = NULL; - kfree(sbi); + free_sbi(sbi); return -EINVAL; } -- 2.43.2