[PATCH] nvidiafb: Use generic DDC reading

[mv-sheeva.git] / fs / pipe.c

diff --git a/fs/pipe.c b/fs/pipe.c
index 2e60e1c8815e1204aa2b5a814d293d849e27c1d6..b1626f269a3445e38f34c1bc338734e0893bbd32 100644 (file)
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -874,87 +874,118 @@ fail_inode:
        return NULL;
 }
 
-int do_pipe(int *fd)
+struct file *create_write_pipe(void)
 {
-       struct qstr this;
-       char name[32];
+       int err;
+       struct inode *inode;
+       struct file *f;
        struct dentry *dentry;
-       struct inode * inode;
-       struct file *f1, *f2;
-       int error;
-       int i, j;
-
-       error = -ENFILE;
-       f1 = get_empty_filp();
-       if (!f1)
-               goto no_files;
-
-       f2 = get_empty_filp();
-       if (!f2)
-               goto close_f1;
+       char name[32];
+       struct qstr this;
 
+       f = get_empty_filp();
+       if (!f)
+               return ERR_PTR(-ENFILE);
+       err = -ENFILE;
        inode = get_pipe_inode();
        if (!inode)
-               goto close_f12;
+               goto err_file;
 
-       error = get_unused_fd();
-       if (error < 0)
-               goto close_f12_inode;
-       i = error;
-
-       error = get_unused_fd();
-       if (error < 0)
-               goto close_f12_inode_i;
-       j = error;
-
-       error = -ENOMEM;
        sprintf(name, "[%lu]", inode->i_ino);
        this.name = name;
        this.len = strlen(name);
        this.hash = inode->i_ino; /* will go */
+       err = -ENOMEM;
        dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &this);
        if (!dentry)
-               goto close_f12_inode_i_j;
+               goto err_inode;
 
        dentry->d_op = &pipefs_dentry_operations;
        d_add(dentry, inode);
-       f1->f_vfsmnt = f2->f_vfsmnt = mntget(mntget(pipe_mnt));
-       f1->f_dentry = f2->f_dentry = dget(dentry);
-       f1->f_mapping = f2->f_mapping = inode->i_mapping;
-
-       /* read file */
-       f1->f_pos = f2->f_pos = 0;
-       f1->f_flags = O_RDONLY;
-       f1->f_op = &read_pipe_fops;
-       f1->f_mode = FMODE_READ;
-       f1->f_version = 0;
-
-       /* write file */
-       f2->f_flags = O_WRONLY;
-       f2->f_op = &write_pipe_fops;
-       f2->f_mode = FMODE_WRITE;
-       f2->f_version = 0;
-
-       fd_install(i, f1);
-       fd_install(j, f2);
-       fd[0] = i;
-       fd[1] = j;
+       f->f_vfsmnt = mntget(pipe_mnt);
+       f->f_dentry = dentry;
+       f->f_mapping = inode->i_mapping;
 
-       return 0;
+       f->f_flags = O_WRONLY;
+       f->f_op = &write_pipe_fops;
+       f->f_mode = FMODE_WRITE;
+       f->f_version = 0;
 
-close_f12_inode_i_j:
-       put_unused_fd(j);
-close_f12_inode_i:
-       put_unused_fd(i);
-close_f12_inode:
+       return f;
+
+ err_inode:
        free_pipe_info(inode);
        iput(inode);
-close_f12:
-       put_filp(f2);
-close_f1:
-       put_filp(f1);
-no_files:
-       return error;   
+ err_file:
+       put_filp(f);
+       return ERR_PTR(err);
+}
+
+void free_write_pipe(struct file *f)
+{
+       mntput(f->f_vfsmnt);
+       dput(f->f_dentry);
+       put_filp(f);
+}
+
+struct file *create_read_pipe(struct file *wrf)
+{
+       struct file *f = get_empty_filp();
+       if (!f)
+               return ERR_PTR(-ENFILE);
+
+       /* Grab pipe from the writer */
+       f->f_vfsmnt = mntget(wrf->f_vfsmnt);
+       f->f_dentry = dget(wrf->f_dentry);
+       f->f_mapping = wrf->f_dentry->d_inode->i_mapping;
+
+       f->f_pos = 0;
+       f->f_flags = O_RDONLY;
+       f->f_op = &read_pipe_fops;
+       f->f_mode = FMODE_READ;
+       f->f_version = 0;
+
+       return f;
+}
+
+int do_pipe(int *fd)
+{
+       struct file *fw, *fr;
+       int error;
+       int fdw, fdr;
+
+       fw = create_write_pipe();
+       if (IS_ERR(fw))
+               return PTR_ERR(fw);
+       fr = create_read_pipe(fw);
+       error = PTR_ERR(fr);
+       if (IS_ERR(fr))
+               goto err_write_pipe;
+
+       error = get_unused_fd();
+       if (error < 0)
+               goto err_read_pipe;
+       fdr = error;
+
+       error = get_unused_fd();
+       if (error < 0)
+               goto err_fdr;
+       fdw = error;
+
+       fd_install(fdr, fr);
+       fd_install(fdw, fw);
+       fd[0] = fdr;
+       fd[1] = fdw;
+
+       return 0;
+
+ err_fdr:
+       put_unused_fd(fdr);
+ err_read_pipe:
+       put_filp(fr);
+ err_write_pipe:
+       free_write_pipe(fw);
+       return error;
 }
 
 /*