In former commit, actual operations for each ioctl is re-designed to get data in kernel space. Therefore, no need to cast pointer in kernel space to user space.
This commit applies optimization to in-kernel path of ioctl.
Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp --- sound/core/seq/seq_clientmgr.c | 36 +++++++++++++----------------------- 1 file changed, 13 insertions(+), 23 deletions(-)
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c index 586f9cd..449eb7a 100644 --- a/sound/core/seq/seq_clientmgr.c +++ b/sound/core/seq/seq_clientmgr.c @@ -2216,23 +2216,6 @@ static const struct seq_ioctl_table { { 0, NULL }, };
-static int snd_seq_do_ioctl(struct snd_seq_client *client, unsigned int cmd, - void __user *arg) -{ - const struct seq_ioctl_table *p; - - if (! arg) - return -EFAULT; - for (p = ioctl_tables; p->cmd; p++) { - if (p->cmd == cmd) - return p->func(client, arg); - } - pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n", - cmd, _IOC_TYPE(cmd), _IOC_NR(cmd)); - return -ENOTTY; -} - - static long snd_seq_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -2484,16 +2467,23 @@ EXPORT_SYMBOL(snd_seq_kernel_client_dispatch); int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg) { struct snd_seq_client *client; - mm_segment_t fs; - int result; + const struct seq_ioctl_table *p;
client = clientptr(clientid); if (client == NULL) return -ENXIO; - fs = snd_enter_user(); - result = snd_seq_do_ioctl(client, cmd, (void __force __user *)arg); - snd_leave_user(fs); - return result; + + for (p = ioctl_tables; p->cmd > 0; ++p) { + if (p->cmd == cmd) + break; + } + if (p->cmd == 0) { + pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n", + cmd, _IOC_TYPE(cmd), _IOC_NR(cmd)); + return -ENOTTY; + } + + return p->func(client, arg); }
EXPORT_SYMBOL(snd_seq_kernel_client_ctl);