X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffile_table.c;h=986ff4ed0a7cbf56d258b290635c32203284c565;hb=6131a2601f42cd7fdbac0e960713396fe68af59f;hp=ce3f39a4798a362c615ed51a2be83e4b616c8a86;hpb=4975e45ff66845c9acc6c8619e80ef15eadf785e;p=linux-2.6-omap-h63xx.git

diff --git a/fs/file_table.c b/fs/file_table.c
index ce3f39a4798..986ff4ed0a7 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -83,6 +83,12 @@ int proc_nr_files(ctl_table *table, int write, struct file *filp,
 /* Find an unused file structure and return a pointer to it.
  * Returns NULL, if there are no more free file structures or
  * we run out of memory.
+ *
+ * Be very careful using this.  You are responsible for
+ * getting write access to any mount that you might assign
+ * to this filp, if it is opened for write.  If this is not
+ * done, you will imbalance int the mount's writer count
+ * and a warning at __fput() time.
  */
 struct file *get_empty_filp(void)
 {
@@ -137,7 +143,67 @@ fail:
 
 EXPORT_SYMBOL(get_empty_filp);
 
-void fastcall fput(struct file *file)
+/**
+ * alloc_file - allocate and initialize a 'struct file'
+ * @mnt: the vfsmount on which the file will reside
+ * @dentry: the dentry representing the new file
+ * @mode: the mode with which the new file will be opened
+ * @fop: the 'struct file_operations' for the new file
+ *
+ * Use this instead of get_empty_filp() to get a new
+ * 'struct file'.  Do so because of the same initialization
+ * pitfalls reasons listed for init_file().  This is a
+ * preferred interface to using init_file().
+ *
+ * If all the callers of init_file() are eliminated, its
+ * code should be moved into this function.
+ */
+struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry,
+		mode_t mode, const struct file_operations *fop)
+{
+	struct file *file;
+	struct path;
+
+	file = get_empty_filp();
+	if (!file)
+		return NULL;
+
+	init_file(file, mnt, dentry, mode, fop);
+	return file;
+}
+EXPORT_SYMBOL(alloc_file);
+
+/**
+ * init_file - initialize a 'struct file'
+ * @file: the already allocated 'struct file' to initialized
+ * @mnt: the vfsmount on which the file resides
+ * @dentry: the dentry representing this file
+ * @mode: the mode the file is opened with
+ * @fop: the 'struct file_operations' for this file
+ *
+ * Use this instead of setting the members directly.  Doing so
+ * avoids making mistakes like forgetting the mntget() or
+ * forgetting to take a write on the mnt.
+ *
+ * Note: This is a crappy interface.  It is here to make
+ * merging with the existing users of get_empty_filp()
+ * who have complex failure logic easier.  All users
+ * of this should be moving to alloc_file().
+ */
+int init_file(struct file *file, struct vfsmount *mnt, struct dentry *dentry,
+	   mode_t mode, const struct file_operations *fop)
+{
+	int error = 0;
+	file->f_path.dentry = dentry;
+	file->f_path.mnt = mntget(mnt);
+	file->f_mapping = dentry->d_inode->i_mapping;
+	file->f_mode = mode;
+	file->f_op = fop;
+	return error;
+}
+EXPORT_SYMBOL(init_file);
+
+void fput(struct file *file)
 {
 	if (atomic_dec_and_test(&file->f_count))
 		__fput(file);
@@ -148,7 +214,7 @@ EXPORT_SYMBOL(fput);
 /* __fput is called from task context when aio completion releases the last
  * last use of a struct file *.  Do not use otherwise.
  */
-void fastcall __fput(struct file *file)
+void __fput(struct file *file)
 {
 	struct dentry *dentry = file->f_path.dentry;
 	struct vfsmount *mnt = file->f_path.mnt;
@@ -181,7 +247,7 @@ void fastcall __fput(struct file *file)
 	mntput(mnt);
 }
 
-struct file fastcall *fget(unsigned int fd)
+struct file *fget(unsigned int fd)
 {
 	struct file *file;
 	struct files_struct *files = current->files;
@@ -209,7 +275,7 @@ EXPORT_SYMBOL(fget);
  * and a flag is returned to be passed to the corresponding fput_light().
  * There must not be a cloning between an fget_light/fput_light pair.
  */
-struct file fastcall *fget_light(unsigned int fd, int *fput_needed)
+struct file *fget_light(unsigned int fd, int *fput_needed)
 {
 	struct file *file;
 	struct files_struct *files = current->files;
@@ -263,12 +329,11 @@ void file_kill(struct file *file)
 
 int fs_may_remount_ro(struct super_block *sb)
 {
-	struct list_head *p;
+	struct file *file;
 
 	/* Check that no files are currently opened for writing. */
 	file_list_lock();
-	list_for_each(p, &sb->s_files) {
-		struct file *file = list_entry(p, struct file, f_u.fu_list);
+	list_for_each_entry(file, &sb->s_files, f_u.fu_list) {
 		struct inode *inode = file->f_path.dentry->d_inode;
 
 		/* File with pending delete? */