[ALSA] rawmidi: let sparse know what is going on _for real_

snd_rawmidi_kernel_read1/write1 weren't annotated but used
copy_to_user/copy_from_user when one of parameters (kernel) was equal to 0
remove it and add properly annotated parameter

Signed-off-by: Marcin Ślusarz <marcin.slusarz@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

1 files changed, 21 insertions, 19 deletions

diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index f94694cb47f8..f7ea7287c59c 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -911,7 +911,8 @@ int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
 }
 
 static long snd_rawmidi_kernel_read1(struct snd_rawmidi_substream *substream,
-                                     unsigned char *buf, long count, int kernel)
+                                     unsigned char __user *userbuf,
+                                     unsigned char *kernelbuf, long count)
 {
         unsigned long flags;
         long result = 0, count1;
@@ -924,11 +925,11 @@ static long snd_rawmidi_kernel_read1(struct snd_rawmidi_substream *substream,
                 spin_lock_irqsave(&runtime->lock, flags);
                 if (count1 > (int)runtime->avail)
                         count1 = runtime->avail;
-                if (kernel) {
-                        memcpy(buf + result, runtime->buffer + runtime->appl_ptr, count1);
-                } else {
+                if (kernelbuf)
+                        memcpy(kernelbuf + result, runtime->buffer + runtime->appl_ptr, count1);
+                if (userbuf) {
                         spin_unlock_irqrestore(&runtime->lock, flags);
-                        if (copy_to_user((char __user *)buf + result,
+                        if (copy_to_user(userbuf + result,
                                          runtime->buffer + runtime->appl_ptr, count1)) {
                                 return result > 0 ? result : -EFAULT;
                         }
@@ -948,7 +949,7 @@ long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
                              unsigned char *buf, long count)
 {
         snd_rawmidi_input_trigger(substream, 1);
-        return snd_rawmidi_kernel_read1(substream, buf, count, 1);
+        return snd_rawmidi_kernel_read1(substream, NULL/*userbuf*/, buf, count);
 }
 
 static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t count,
@@ -989,8 +990,9 @@ static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t coun
                 }
                 spin_unlock_irq(&runtime->lock);
                 count1 = snd_rawmidi_kernel_read1(substream,
-                                                  (unsigned char __force *)buf,
-                                                  count, 0);
+                                                  (unsigned char __user *)buf,
+                                                  NULL/*kernelbuf*/,
+                                                  count);
                 if (count1 < 0)
                         return result > 0 ? result : count1;
                 result += count1;
@@ -1131,13 +1133,15 @@ int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
 }
 
 static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
-                                      const unsigned char *buf, long count, int kernel)
+                                      const unsigned char __user *userbuf,
+                                      const unsigned char *kernelbuf,
+                                      long count)
 {
         unsigned long flags;
         long count1, result;
         struct snd_rawmidi_runtime *runtime = substream->runtime;
 
-        snd_assert(buf != NULL, return -EINVAL);
+        snd_assert(kernelbuf != NULL || userbuf != NULL, return -EINVAL);
         snd_assert(runtime->buffer != NULL, return -EINVAL);
 
         result = 0;
@@ -1154,12 +1158,13 @@ static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
                         count1 = count;
                 if (count1 > (long)runtime->avail)
                         count1 = runtime->avail;
-                if (kernel) {
-                        memcpy(runtime->buffer + runtime->appl_ptr, buf, count1);
-                } else {
+                if (kernelbuf)
+                        memcpy(runtime->buffer + runtime->appl_ptr,
+                               kernelbuf + result, count1);
+                else if (userbuf) {
                         spin_unlock_irqrestore(&runtime->lock, flags);
                         if (copy_from_user(runtime->buffer + runtime->appl_ptr,
-                                           (char __user *)buf, count1)) {
+                                           userbuf + result, count1)) {
                                 spin_lock_irqsave(&runtime->lock, flags);
                                 result = result > 0 ? result : -EFAULT;
                                 goto __end;
@@ -1170,7 +1175,6 @@ static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
                 runtime->appl_ptr %= runtime->buffer_size;
                 runtime->avail -= count1;
                 result += count1;
-                buf += count1;
                 count -= count1;
         }
       __end:
@@ -1184,7 +1188,7 @@ static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
                               const unsigned char *buf, long count)
 {
-        return snd_rawmidi_kernel_write1(substream, buf, count, 1);
+        return snd_rawmidi_kernel_write1(substream, NULL, buf, count);
 }
 
 static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
@@ -1224,9 +1228,7 @@ static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
                         spin_lock_irq(&runtime->lock);
                 }
                 spin_unlock_irq(&runtime->lock);
-                count1 = snd_rawmidi_kernel_write1(substream,
-                                                   (unsigned char __force *)buf,
-                                                   count, 0);
+                count1 = snd_rawmidi_kernel_write1(substream, buf, NULL, count);
                 if (count1 < 0)
                         return result > 0 ? result : count1;
                 result += count1;