From db1dd4d376134eba0e08af523b61cc566a4ea1cd Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Fri, 6 Feb 2009 15:25:24 -0700 Subject: Use f_lock to protect f_flags Traditionally, changes to struct file->f_flags have been done under BKL protection, or with no protection at all. This patch causes all f_flags changes after file open/creation time to be done under protection of f_lock. This allows the removal of some BKL usage and fixes a number of longstanding (if microscopic) races. Reviewed-by: Christoph Hellwig Cc: Al Viro Signed-off-by: Jonathan Corbet --- sound/oss/au1550_ac97.c | 2 ++ sound/oss/audio.c | 2 ++ sound/oss/sh_dac_audio.c | 2 ++ sound/oss/swarm_cs4297a.c | 2 ++ sound/oss/vwsnd.c | 2 ++ 5 files changed, 10 insertions(+) (limited to 'sound/oss') diff --git a/sound/oss/au1550_ac97.c b/sound/oss/au1550_ac97.c index 81e1f443d094..4191acccbcdb 100644 --- a/sound/oss/au1550_ac97.c +++ b/sound/oss/au1550_ac97.c @@ -1627,7 +1627,9 @@ au1550_ioctl(struct inode *inode, struct file *file, unsigned int cmd, sizeof(abinfo)) ? -EFAULT : 0; case SNDCTL_DSP_NONBLOCK: + spin_lock(&file->f_lock); file->f_flags |= O_NONBLOCK; + spin_unlock(&file->f_lock); return 0; case SNDCTL_DSP_GETODELAY: diff --git a/sound/oss/audio.c b/sound/oss/audio.c index 89bd27a5e865..b69c05b7ea7b 100644 --- a/sound/oss/audio.c +++ b/sound/oss/audio.c @@ -433,7 +433,9 @@ int audio_ioctl(int dev, struct file *file, unsigned int cmd, void __user *arg) return dma_ioctl(dev, cmd, arg); case SNDCTL_DSP_NONBLOCK: + spin_lock(&file->f_lock); file->f_flags |= O_NONBLOCK; + spin_unlock(&file->f_lock); return 0; case SNDCTL_DSP_GETCAPS: diff --git a/sound/oss/sh_dac_audio.c b/sound/oss/sh_dac_audio.c index e5d423994918..78cfb66e4c59 100644 --- a/sound/oss/sh_dac_audio.c +++ b/sound/oss/sh_dac_audio.c @@ -135,7 +135,9 @@ static int dac_audio_ioctl(struct inode *inode, struct file *file, return put_user(AFMT_U8, (int *)arg); case SNDCTL_DSP_NONBLOCK: + spin_lock(&file->f_lock); file->f_flags |= O_NONBLOCK; + spin_unlock(&file->f_lock); return 0; case SNDCTL_DSP_GETCAPS: diff --git a/sound/oss/swarm_cs4297a.c b/sound/oss/swarm_cs4297a.c index 41562ecde5bb..1edab7b4ea83 100644 --- a/sound/oss/swarm_cs4297a.c +++ b/sound/oss/swarm_cs4297a.c @@ -2200,7 +2200,9 @@ static int cs4297a_ioctl(struct inode *inode, struct file *file, sizeof(abinfo)) ? -EFAULT : 0; case SNDCTL_DSP_NONBLOCK: + spin_lock(&file->f_lock); file->f_flags |= O_NONBLOCK; + spin_unlock(&file->f_lock); return 0; case SNDCTL_DSP_GETODELAY: diff --git a/sound/oss/vwsnd.c b/sound/oss/vwsnd.c index 78b8acc7c3b9..187f72750e8f 100644 --- a/sound/oss/vwsnd.c +++ b/sound/oss/vwsnd.c @@ -2673,7 +2673,9 @@ static int vwsnd_audio_do_ioctl(struct inode *inode, case SNDCTL_DSP_NONBLOCK: /* _SIO ('P',14) */ DBGX("SNDCTL_DSP_NONBLOCK\n"); + spin_lock(&file->f_lock); file->f_flags |= O_NONBLOCK; + spin_unlock(&file->f_lock); return 0; case SNDCTL_DSP_RESET: /* _SIO ('P', 0) */ -- cgit v1.2.3-55-g7522