fsnotify: make fasync generic for both inotify and fanotify

inotify is supposed to support async signal notification when information
is available on the inotify fd.  This patch moves that support to generic
fsnotify functions so it can be used by all notification mechanisms.

Signed-off-by: Eric Paris <eparis@redhat.com>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 1218d10424d039f35d7efd4a8f5d8dea815b8b98..f0e7a57bc8990419e75b48988e523e1ed6efbea4 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -414,6 +414,10 @@ static int fanotify_release(struct inode *ignored, struct file *file)
 
        wake_up(&group->fanotify_data.access_waitq);
 #endif
+
+       if (file->f_flags & FASYNC)
+               fsnotify_fasync(-1, file, 0);
+
        /* matches the fanotify_init->fsnotify_alloc_group */
        fsnotify_destroy_group(group);
 

diff --git a/fs/notify/group.c b/fs/notify/group.c
index 1f7305711fc96dac2d97d4fa6b8edf6b84967c5c..bd2625bd88b47a7b2961ec0d43b77f5675a80ad6 100644 (file)
--- a/fs/notify/group.c
+++ b/fs/notify/group.c
@@ -102,3 +102,10 @@ struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
 
        return group;
 }
+
+int fsnotify_fasync(int fd, struct file *file, int on)
+{
+       struct fsnotify_group *group = file->private_data;
+
+       return fasync_helper(fd, file, on, &group->fsn_fa) >= 0 ? 0 : -EIO;
+}

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 00ff82ff7c9f8843d27c6991e4698907ba4a3394..68f7bec1e664129466570644f6525a764f6d119e 100644 (file)
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -280,19 +280,15 @@ static ssize_t inotify_read(struct file *file, char __user *buf,
        return ret;
 }
 
-static int inotify_fasync(int fd, struct file *file, int on)
-{
-       struct fsnotify_group *group = file->private_data;
-
-       return fasync_helper(fd, file, on, &group->inotify_data.fa) >= 0 ? 0 : -EIO;
-}
-
 static int inotify_release(struct inode *ignored, struct file *file)
 {
        struct fsnotify_group *group = file->private_data;
 
        pr_debug("%s: group=%p\n", __func__, group);
 
+       if (file->f_flags & FASYNC)
+               fsnotify_fasync(-1, file, 0);
+
        /* free this group, matching get was inotify_init->fsnotify_obtain_group */
        fsnotify_destroy_group(group);
 
@@ -335,7 +331,7 @@ static long inotify_ioctl(struct file *file, unsigned int cmd,
 static const struct file_operations inotify_fops = {
        .poll           = inotify_poll,
        .read           = inotify_read,
-       .fasync         = inotify_fasync,
+       .fasync         = fsnotify_fasync,
        .release        = inotify_release,
        .unlocked_ioctl = inotify_ioctl,
        .compat_ioctl   = inotify_ioctl,
@@ -706,7 +702,6 @@ static struct fsnotify_group *inotify_new_group(unsigned int max_events)
        spin_lock_init(&group->inotify_data.idr_lock);
        idr_init(&group->inotify_data.idr);
        group->inotify_data.last_wd = 0;
-       group->inotify_data.fa = NULL;
        group->inotify_data.user = get_current_user();
 
        if (atomic_inc_return(&group->inotify_data.user->inotify_devs) >

diff --git a/fs/notify/notification.c b/fs/notify/notification.c
index c887b1378f7ed5087eca0df3ca745e15d9a88cc6..b3963d8c998846207eb8a0c48590c14d566630f4 100644 (file)
--- a/fs/notify/notification.c
+++ b/fs/notify/notification.c
@@ -225,6 +225,7 @@ alloc_holder:
        mutex_unlock(&group->notification_mutex);
 
        wake_up(&group->notification_waitq);
+       kill_fasync(&group->fsn_fa, SIGIO, POLL_IN);
        return return_event;
 }
 

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 1af2f6a722c0defa7b3f9d88f03bfb45a507a011..d5b0910d49615ee01cf3255818d99e78241cb09f 100644 (file)
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -148,6 +148,8 @@ struct fsnotify_group {
                                         * a group */
        struct list_head marks_list;    /* all inode marks for this group */
 
+       struct fasync_struct    *fsn_fa;    /* async notification */
+
        /* groups can define private fields here or use the void *private */
        union {
                void *private;
@@ -156,7 +158,6 @@ struct fsnotify_group {
                        spinlock_t      idr_lock;
                        struct idr      idr;
                        u32             last_wd;
-                       struct fasync_struct    *fa;    /* async notification */
                        struct user_struct      *user;
                } inotify_data;
 #endif
@@ -368,6 +369,8 @@ extern void fsnotify_get_group(struct fsnotify_group *group);
 extern void fsnotify_put_group(struct fsnotify_group *group);
 /* destroy group */
 extern void fsnotify_destroy_group(struct fsnotify_group *group);
+/* fasync handler function */
+extern int fsnotify_fasync(int fd, struct file *file, int on);
 /* take a reference to an event */
 extern void fsnotify_get_event(struct fsnotify_event *event);
 extern void fsnotify_put_event(struct fsnotify_event *event);