nfsd4: make recall callback an asynchronous rpc

[safe/jmp/linux-2.6] / fs / fcntl.c

diff --git a/fs/fcntl.c b/fs/fcntl.c
index 87c39f1..cc8e4de 100644 (file)
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -19,6 +19,7 @@
 #include <linux/signal.h>
 #include <linux/rcupdate.h>
 #include <linux/pid_namespace.h>
+#include <linux/smp_lock.h>
 
 #include <asm/poll.h>
 #include <asm/siginfo.h>
@@ -49,7 +50,7 @@ static int get_close_on_exec(unsigned int fd)
        return res;
 }
 
-asmlinkage long sys_dup3(unsigned int oldfd, unsigned int newfd, int flags)
+SYSCALL_DEFINE3(dup3, unsigned int, oldfd, unsigned int, newfd, int, flags)
 {
        int err = -EBADF;
        struct file * file, *tofree;
@@ -112,7 +113,7 @@ out_unlock:
        return err;
 }
 
-asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd)
+SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd)
 {
        if (unlikely(newfd == oldfd)) { /* corner case */
                struct files_struct *files = current->files;
@@ -125,7 +126,7 @@ asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd)
        return sys_dup3(oldfd, newfd, 0);
 }
 
-asmlinkage long sys_dup(unsigned int fildes)
+SYSCALL_DEFINE1(dup, unsigned int, fildes)
 {
        int ret = -EBADF;
        struct file *file = fget(fildes);
@@ -140,7 +141,7 @@ asmlinkage long sys_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)
 {
@@ -175,15 +176,21 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
        if (error)
                return error;
 
-       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;
-               }
+       /*
+        * ->fasync() is responsible for setting the FASYNC bit.
+        */
+       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:
        return error;
 }
@@ -328,7 +335,7 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
        return err;
 }
 
-asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg)
+SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
 {      
        struct file *filp;
        long err = -EBADF;
@@ -351,7 +358,8 @@ out:
 }
 
 #if BITS_PER_LONG == 32
-asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg)
+SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
+               unsigned long, arg)
 {      
        struct file * filp;
        long err;
@@ -508,7 +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.
  */
@@ -523,6 +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) {
@@ -547,7 +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;
 }