X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=fs%2Ffcntl.c;h=9679fcbdeaa0b7440992db5baec1698e90704588;hb=336dd1f70ff62d7dd8655228caed4c5bfc818c56;hp=e632da761fc11cd19b8637bcad23b1f5562d7382;hpb=c58310bf4933986513020fa90b4190c7492995ae;p=linux-block.git

diff --git a/fs/fcntl.c b/fs/fcntl.c
index e632da761fc1..9679fcbdeaa0 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -9,9 +9,9 @@
 #include <linux/mm.h>
 #include <linux/fs.h>
 #include <linux/file.h>
+#include <linux/fdtable.h>
 #include <linux/capability.h>
 #include <linux/dnotify.h>
-#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/security.h>
@@ -55,14 +55,16 @@ static int get_close_on_exec(unsigned int fd)
  * file_lock held for write.
  */
 
-static int locate_fd(struct files_struct *files, 
-			    struct file *file, unsigned int orig_start)
+static int locate_fd(unsigned int orig_start, int cloexec)
 {
+	struct files_struct *files = current->files;
 	unsigned int newfd;
 	unsigned int start;
 	int error;
 	struct fdtable *fdt;
 
+	spin_lock(&files->file_lock);
+
 	error = -EINVAL;
 	if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
 		goto out;
@@ -97,53 +99,42 @@ repeat:
 	if (error)
 		goto repeat;
 
-	/*
-	 * We reacquired files_lock, so we are safe as long as
-	 * we reacquire the fdtable pointer and use it while holding
-	 * the lock, no one can free it during that time.
-	 */
 	if (start <= files->next_fd)
 		files->next_fd = newfd + 1;
 
+	FD_SET(newfd, fdt->open_fds);
+	if (cloexec)
+		FD_SET(newfd, fdt->close_on_exec);
+	else
+		FD_CLR(newfd, fdt->close_on_exec);
 	error = newfd;
-	
+
 out:
+	spin_unlock(&files->file_lock);
 	return error;
 }
 
 static int dupfd(struct file *file, unsigned int start, int cloexec)
 {
-	struct files_struct * files = current->files;
-	struct fdtable *fdt;
-	int fd;
-
-	spin_lock(&files->file_lock);
-	fd = locate_fd(files, file, start);
-	if (fd >= 0) {
-		/* locate_fd() may have expanded fdtable, load the ptr */
-		fdt = files_fdtable(files);
-		FD_SET(fd, fdt->open_fds);
-		if (cloexec)
-			FD_SET(fd, fdt->close_on_exec);
-		else
-			FD_CLR(fd, fdt->close_on_exec);
-		spin_unlock(&files->file_lock);
+	int fd = locate_fd(start, cloexec);
+	if (fd >= 0)
 		fd_install(fd, file);
-	} else {
-		spin_unlock(&files->file_lock);
+	else
 		fput(file);
-	}
 
 	return fd;
 }
 
-asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd)
+asmlinkage long sys_dup3(unsigned int oldfd, unsigned int newfd, int flags)
 {
 	int err = -EBADF;
 	struct file * file, *tofree;
 	struct files_struct * files = current->files;
 	struct fdtable *fdt;
 
+	if ((flags & ~O_CLOEXEC) != 0)
+		return -EINVAL;
+
 	spin_lock(&files->file_lock);
 	if (!(file = fcheck(oldfd)))
 		goto out_unlock;
@@ -175,7 +166,10 @@ asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd)
 
 	rcu_assign_pointer(fdt->fd[newfd], file);
 	FD_SET(newfd, fdt->open_fds);
-	FD_CLR(newfd, fdt->close_on_exec);
+	if (flags & O_CLOEXEC)
+		FD_SET(newfd, fdt->close_on_exec);
+	else
+		FD_CLR(newfd, fdt->close_on_exec);
 	spin_unlock(&files->file_lock);
 
 	if (tofree)
@@ -193,6 +187,11 @@ out_fput:
 	goto out;
 }
 
+asmlinkage long sys_dup2(unsigned int oldfd, unsigned int newfd)
+{
+	return sys_dup3(oldfd, newfd, 0);
+}
+
 asmlinkage long sys_dup(unsigned int fildes)
 {
 	int ret = -EBADF;
@@ -238,7 +237,6 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 	if (error)
 		return error;
 
-	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);
@@ -249,7 +247,6 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
 
 	filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
  out:
-	unlock_kernel();
 	return error;
 }