X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Ffile_table.c;h=6d27befe2d48ff5fbb13a45c5cd86618777bbbd9;hb=e9720acd728a46cb40daa52c99a979f7c4ff195c;hp=bcea1998b4de48b56fed18334159c34b2559d6c5;hpb=5a6b7951bfcca7f45f44269ea87417c74558daf8;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/file_table.c b/fs/file_table.c
index bcea199..6d27bef 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -5,13 +5,11 @@
  *  Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
  */
 
-#include <linux/config.h>
 #include <linux/string.h>
 #include <linux/slab.h>
 #include <linux/file.h>
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/smp_lock.h>
 #include <linux/fs.h>
 #include <linux/security.h>
 #include <linux/eventpoll.h>
@@ -100,16 +98,15 @@ struct file *get_empty_filp(void)
 		 * percpu_counters are inaccurate.  Do an expensive check before
 		 * we go and fail.
 		 */
-		if (percpu_counter_sum(&nr_files) >= files_stat.max_files)
+		if (percpu_counter_sum_positive(&nr_files) >= files_stat.max_files)
 			goto over;
 	}
 
-	f = kmem_cache_alloc(filp_cachep, GFP_KERNEL);
+	f = kmem_cache_zalloc(filp_cachep, GFP_KERNEL);
 	if (f == NULL)
 		goto fail;
 
 	percpu_counter_inc(&nr_files);
-	memset(f, 0, sizeof(*f));
 	if (security_file_alloc(f))
 		goto fail_sec;
 
@@ -140,7 +137,67 @@ 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);
@@ -151,10 +208,10 @@ 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_dentry;
-	struct vfsmount *mnt = file->f_vfsmnt;
+	struct dentry *dentry = file->f_path.dentry;
+	struct vfsmount *mnt = file->f_path.mnt;
 	struct inode *inode = dentry->d_inode;
 
 	might_sleep();
@@ -170,20 +227,21 @@ void fastcall __fput(struct file *file)
 	if (file->f_op && file->f_op->release)
 		file->f_op->release(inode, file);
 	security_file_free(file);
-	if (unlikely(inode->i_cdev != NULL))
+	if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL))
 		cdev_put(inode->i_cdev);
 	fops_put(file->f_op);
 	if (file->f_mode & FMODE_WRITE)
 		put_write_access(inode);
+	put_pid(file->f_owner.pid);
 	file_kill(file);
-	file->f_dentry = NULL;
-	file->f_vfsmnt = NULL;
+	file->f_path.dentry = NULL;
+	file->f_path.mnt = NULL;
 	file_free(file);
 	dput(dentry);
 	mntput(mnt);
 }
 
-struct file fastcall *fget(unsigned int fd)
+struct file *fget(unsigned int fd)
 {
 	struct file *file;
 	struct files_struct *files = current->files;
@@ -211,7 +269,7 @@ 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;
@@ -265,13 +323,12 @@ 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);
-		struct inode *inode = file->f_dentry->d_inode;
+	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? */
 		if (inode->i_nlink == 0)
@@ -300,5 +357,5 @@ void __init files_init(unsigned long mempages)
 	if (files_stat.max_files < NR_FILE)
 		files_stat.max_files = NR_FILE;
 	files_defer_init();
-	percpu_counter_init(&nr_files);
+	percpu_counter_init(&nr_files, 0);
 }