X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffcntl.c;h=cc8e4de2fee5f0caefa6c5e00ea4e1abf33359b8;hb=be99ca4dd45b5ffc3ff30b2c80d7103aa1451afc;hp=bd215cc791da53eb9713063600a56ab3edb1c92a;hpb=af7af690397296b663c8bc152a5f79f32abcef24;p=linux-2.6-omap-h63xx.git

diff --git a/fs/fcntl.c b/fs/fcntl.c
index bd215cc791d..cc8e4de2fee 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -141,7 +141,7 @@ SYSCALL_DEFINE1(dup, unsigned int, fildes)
 	return ret;
 }
 
-#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME)
+#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
 
 static int setfl(int fd, struct file * filp, unsigned long arg)
 {
@@ -177,21 +177,21 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 		return error;
 
 	/*
-	 * We still need a lock here for now to keep multiple FASYNC calls
-	 * from racing with each other.
+	 * ->fasync() is responsible for setting the FASYNC bit.
 	 */
-	lock_kernel();
-	if ((arg ^ filp->f_flags) & FASYNC) {
-		if (filp->f_op && filp->f_op->fasync) {
-			error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
-			if (error < 0)
-				goto out;
-		}
+	if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
+			filp->f_op->fasync) {
+		error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
+		if (error < 0)
+			goto out;
+		if (error > 0)
+			error = 0;
 	}
-
+	spin_lock(&filp->f_lock);
 	filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
+	spin_unlock(&filp->f_lock);
+
  out:
-	unlock_kernel();
 	return error;
 }
 
@@ -516,7 +516,7 @@ static DEFINE_RWLOCK(fasync_lock);
 static struct kmem_cache *fasync_cache __read_mostly;
 
 /*
- * fasync_helper() is used by some character device drivers (mainly mice)
+ * fasync_helper() is used by almost all character device drivers
  * to set up the fasync queue. It returns negative on error, 0 if it did
  * no changes and positive if it added/deleted the entry.
  */
@@ -531,6 +531,12 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap
 		if (!new)
 			return -ENOMEM;
 	}
+
+	/*
+	 * We need to take f_lock first since it's not an IRQ-safe
+	 * lock.
+	 */
+	spin_lock(&filp->f_lock);
 	write_lock_irq(&fasync_lock);
 	for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
 		if (fa->fa_file == filp) {
@@ -555,7 +561,12 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap
 		result = 1;
 	}
 out:
+	if (on)
+		filp->f_flags |= FASYNC;
+	else
+		filp->f_flags &= ~FASYNC;
 	write_unlock_irq(&fasync_lock);
+	spin_unlock(&filp->f_lock);
 	return result;
 }