1 files changed, 70 insertions, 3 deletions

diff --git a/fs/open.c b/fs/open.c
index 0d515d161974..a6b054edacba 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -26,6 +26,7 @@
 #include <linux/syscalls.h>
 #include <linux/rcupdate.h>
 #include <linux/audit.h>
+#include <linux/falloc.h>
 
 int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
@@ -352,6 +353,64 @@ asmlinkage long sys_ftruncate64(unsigned int fd, loff_t length)
 }
 #endif
 
+asmlinkage long sys_fallocate(int fd, int mode, loff_t offset, loff_t len)
+{
+        struct file *file;
+        struct inode *inode;
+        long ret = -EINVAL;
+
+        if (offset < 0 || len <= 0)
+                goto out;
+
+        /* Return error if mode is not supported */
+        ret = -EOPNOTSUPP;
+        if (mode && !(mode & FALLOC_FL_KEEP_SIZE))
+                goto out;
+
+        ret = -EBADF;
+        file = fget(fd);
+        if (!file)
+                goto out;
+        if (!(file->f_mode & FMODE_WRITE))
+                goto out_fput;
+        /*
+         * Revalidate the write permissions, in case security policy has
+         * changed since the files were opened.
+         */
+        ret = security_file_permission(file, MAY_WRITE);
+        if (ret)
+                goto out_fput;
+
+        inode = file->f_path.dentry->d_inode;
+
+        ret = -ESPIPE;
+        if (S_ISFIFO(inode->i_mode))
+                goto out_fput;
+
+        ret = -ENODEV;
+        /*
+         * Let individual file system decide if it supports preallocation
+         * for directories or not.
+         */
+        if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
+                goto out_fput;
+
+        ret = -EFBIG;
+        /* Check for wrap through zero too */
+        if (((offset + len) > inode->i_sb->s_maxbytes) || ((offset + len) < 0))
+                goto out_fput;
+
+        if (inode->i_op && inode->i_op->fallocate)
+                ret = inode->i_op->fallocate(inode, mode, offset, len);
+        else
+                ret = -ENOSYS;
+
+out_fput:
+        fput(file);
+out:
+        return ret;
+}
+
 /*
  * access() needs to use the real uid/gid, not the effective uid/gid.
  * We do this by temporarily clearing all FS-related capabilities and
@@ -855,7 +914,7 @@ EXPORT_SYMBOL(dentry_open);
 /*
  * Find an empty file descriptor entry, and mark it busy.
  */
-int get_unused_fd(void)
+int get_unused_fd_flags(int flags)
 {
         struct files_struct * files = current->files;
         int fd, error;
@@ -891,7 +950,10 @@ repeat:
         }
 
         FD_SET(fd, fdt->open_fds);
-        FD_CLR(fd, fdt->close_on_exec);
+        if (flags & O_CLOEXEC)
+                FD_SET(fd, fdt->close_on_exec);
+        else
+                FD_CLR(fd, fdt->close_on_exec);
         files->next_fd = fd + 1;
 #if 1
         /* Sanity check */
@@ -907,6 +969,11 @@ out:
         return error;
 }
 
+int get_unused_fd(void)
+{
+        return get_unused_fd_flags(0);
+}
+
 EXPORT_SYMBOL(get_unused_fd);
 
 static void __put_unused_fd(struct files_struct *files, unsigned int fd)
@@ -959,7 +1026,7 @@ long do_sys_open(int dfd, const char __user *filename, int flags, int mode)
         int fd = PTR_ERR(tmp);
 
         if (!IS_ERR(tmp)) {
-                fd = get_unused_fd();
+                fd = get_unused_fd_flags(flags);
                 if (fd >= 0) {
                         struct file *f = do_filp_open(dfd, tmp, flags, mode);
                         if (IS_ERR(f)) {