[ALSA] Fix control/status mmap with shared PCM substream

The flag to avoid 32bit-incompatible mmap for control/status records
should be outside the pcm substream instance since a substream can be
shared among multiple opens.  Now it's flagged in pcm_file list that
is directly assigned to file->private_data.
Also, removed snd_pcm_add_file() and remove_file() functions and
substream.files field that are not really used in the code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index f84d849..60d40b3 100644 (file)
--- a/include/sound/pcm.h
+++ b/include/sound/pcm.h
@@ -190,7 +190,7 @@ struct snd_pcm_ops {
 
 struct snd_pcm_file {
        struct snd_pcm_substream *substream;
-       struct snd_pcm_file *next;
+       int no_compat_mmap;
 };
 
 struct snd_pcm_hw_rule;
@@ -384,7 +384,6 @@ struct snd_pcm_substream {
        struct snd_info_entry *proc_prealloc_entry;
 #endif
        /* misc flags */
-       unsigned int no_mmap_ctrl: 1;
        unsigned int hw_opened: 1;
 };
 
@@ -402,7 +401,6 @@ struct snd_pcm_str {
        /* -- OSS things -- */
        struct snd_pcm_oss_stream oss;
 #endif
-       struct snd_pcm_file *files;
 #ifdef CONFIG_SND_VERBOSE_PROCFS
        struct snd_info_entry *proc_root;
        struct snd_info_entry *proc_info_entry;

diff --git a/sound/core/pcm_compat.c b/sound/core/pcm_compat.c
index 2b8aab6..2b53979 100644 (file)
--- a/sound/core/pcm_compat.c
+++ b/sound/core/pcm_compat.c
@@ -478,7 +478,7 @@ static long snd_pcm_ioctl_compat(struct file *file, unsigned int cmd, unsigned l
         * mmap of PCM status/control records because of the size
         * incompatibility.
         */
-       substream->no_mmap_ctrl = 1;
+       pcm_file->no_compat_mmap = 1;
 
        switch (cmd) {
        case SNDRV_PCM_IOCTL_PVERSION:

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index 439f047..0224c70 100644 (file)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1992,35 +1992,9 @@ int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream)
        return 0;
 }
 
-static void snd_pcm_add_file(struct snd_pcm_str *str,
-                            struct snd_pcm_file *pcm_file)
-{
-       pcm_file->next = str->files;
-       str->files = pcm_file;
-}
-
-static void snd_pcm_remove_file(struct snd_pcm_str *str,
-                               struct snd_pcm_file *pcm_file)
-{
-       struct snd_pcm_file * pcm_file1;
-       if (str->files == pcm_file) {
-               str->files = pcm_file->next;
-       } else {
-               pcm_file1 = str->files;
-               while (pcm_file1 && pcm_file1->next != pcm_file)
-                       pcm_file1 = pcm_file1->next;
-               if (pcm_file1 != NULL)
-                       pcm_file1->next = pcm_file->next;
-       }
-}
-
 static void pcm_release_private(struct snd_pcm_substream *substream)
 {
-       struct snd_pcm_file *pcm_file = substream->file;
-
        snd_pcm_unlink(substream);
-       snd_pcm_remove_file(substream->pstr, pcm_file);
-       kfree(pcm_file);
 }
 
 void snd_pcm_release_substream(struct snd_pcm_substream *substream)
@@ -2060,7 +2034,6 @@ int snd_pcm_open_substream(struct snd_pcm *pcm, int stream,
                return 0;
        }
 
-       substream->no_mmap_ctrl = 0;
        err = snd_pcm_hw_constraints_init(substream);
        if (err < 0) {
                snd_printd("snd_pcm_hw_constraints_init failed\n");
@@ -2105,19 +2078,16 @@ static int snd_pcm_open_file(struct file *file,
        if (err < 0)
                return err;
 
-       if (substream->ref_count > 1)
-               pcm_file = substream->file;
-       else {
-               pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
-               if (pcm_file == NULL) {
-                       snd_pcm_release_substream(substream);
-                       return -ENOMEM;
-               }
+       pcm_file = kzalloc(sizeof(*pcm_file), GFP_KERNEL);
+       if (pcm_file == NULL) {
+               snd_pcm_release_substream(substream);
+               return -ENOMEM;
+       }
+       pcm_file->substream = substream;
+       if (substream->ref_count == 1) {
                str = substream->pstr;
                substream->file = pcm_file;
                substream->pcm_release = pcm_release_private;
-               pcm_file->substream = substream;
-               snd_pcm_add_file(str, pcm_file);
        }
        file->private_data = pcm_file;
        *rpcm_file = pcm_file;
@@ -2209,6 +2179,7 @@ static int snd_pcm_release(struct inode *inode, struct file *file)
        fasync_helper(-1, file, 0, &substream->runtime->fasync);
        mutex_lock(&pcm->open_mutex);
        snd_pcm_release_substream(substream);
+       kfree(pcm_file);
        mutex_unlock(&pcm->open_mutex);
        wake_up(&pcm->open_wait);
        module_put(pcm->card->module);
@@ -3270,11 +3241,11 @@ static int snd_pcm_mmap(struct file *file, struct vm_area_struct *area)
        offset = area->vm_pgoff << PAGE_SHIFT;
        switch (offset) {
        case SNDRV_PCM_MMAP_OFFSET_STATUS:
-               if (substream->no_mmap_ctrl)
+               if (pcm_file->no_compat_mmap)
                        return -ENXIO;
                return snd_pcm_mmap_status(substream, file, area);
        case SNDRV_PCM_MMAP_OFFSET_CONTROL:
-               if (substream->no_mmap_ctrl)
+               if (pcm_file->no_compat_mmap)
                        return -ENXIO;
                return snd_pcm_mmap_control(substream, file, area);
        default: