[ARM] 4611/2: AT91: Fix GPIO buttons pins on SAM9261-EK.

[linux-2.6-omap-h63xx.git] / fs / file_table.c

diff --git a/fs/file_table.c b/fs/file_table.c
index 24f25a057d9c131f94f1f2eb2400739958d09a95..664e3f2309b89811b028603da0f17a6e266ee9fd 100644 (file)
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -10,7 +10,6 @@
 #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>
@@ -99,16 +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;
 
@@ -139,6 +137,66 @@ fail:
 
 EXPORT_SYMBOL(get_empty_filp);
 
+/**
+ * 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 fastcall fput(struct file *file)
 {
        if (atomic_dec_and_test(&file->f_count))
@@ -152,8 +210,8 @@ EXPORT_SYMBOL(fput);
  */
 void fastcall __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();
@@ -176,8 +234,8 @@ void fastcall __fput(struct file *file)
                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);
@@ -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)