Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 255 insertions, 0 deletions

diff --git a/fs/file_table.c b/fs/file_table.c
new file mode 100644
index 00000000000..03d83cb686b
--- /dev/null
+++ b/fs/file_table.c
@@ -0,0 +1,255 @@
+/*
+ *  linux/fs/file_table.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *  Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
+ */
+
+#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>
+#include <linux/mount.h>
+#include <linux/cdev.h>
+
+/* sysctl tunables... */
+struct files_stat_struct files_stat = {
+	.max_files = NR_FILE
+};
+
+EXPORT_SYMBOL(files_stat); /* Needed by unix.o */
+
+/* public. Not pretty! */
+ __cacheline_aligned_in_smp DEFINE_SPINLOCK(files_lock);
+
+static DEFINE_SPINLOCK(filp_count_lock);
+
+/* slab constructors and destructors are called from arbitrary
+ * context and must be fully threaded - use a local spinlock
+ * to protect files_stat.nr_files
+ */
+void filp_ctor(void * objp, struct kmem_cache_s *cachep, unsigned long cflags)
+{
+	if ((cflags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+	    SLAB_CTOR_CONSTRUCTOR) {
+		unsigned long flags;
+		spin_lock_irqsave(&filp_count_lock, flags);
+		files_stat.nr_files++;
+		spin_unlock_irqrestore(&filp_count_lock, flags);
+	}
+}
+
+void filp_dtor(void * objp, struct kmem_cache_s *cachep, unsigned long dflags)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&filp_count_lock, flags);
+	files_stat.nr_files--;
+	spin_unlock_irqrestore(&filp_count_lock, flags);
+}
+
+static inline void file_free(struct file *f)
+{
+	kmem_cache_free(filp_cachep, f);
+}
+
+/* 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.
+ */
+struct file *get_empty_filp(void)
+{
+static int old_max;
+	struct file * f;
+
+	/*
+	 * Privileged users can go above max_files
+	 */
+	if (files_stat.nr_files < files_stat.max_files ||
+				capable(CAP_SYS_ADMIN)) {
+		f = kmem_cache_alloc(filp_cachep, GFP_KERNEL);
+		if (f) {
+			memset(f, 0, sizeof(*f));
+			if (security_file_alloc(f)) {
+				file_free(f);
+				goto fail;
+			}
+			eventpoll_init_file(f);
+			atomic_set(&f->f_count, 1);
+			f->f_uid = current->fsuid;
+			f->f_gid = current->fsgid;
+			rwlock_init(&f->f_owner.lock);
+			/* f->f_version: 0 */
+			INIT_LIST_HEAD(&f->f_list);
+			f->f_maxcount = INT_MAX;
+			return f;
+		}
+	}
+
+	/* Ran out of filps - report that */
+	if (files_stat.max_files >= old_max) {
+		printk(KERN_INFO "VFS: file-max limit %d reached\n",
+					files_stat.max_files);
+		old_max = files_stat.max_files;
+	} else {
+		/* Big problems... */
+		printk(KERN_WARNING "VFS: filp allocation failed\n");
+	}
+fail:
+	return NULL;
+}
+
+EXPORT_SYMBOL(get_empty_filp);
+
+void fastcall fput(struct file *file)
+{
+	if (atomic_dec_and_test(&file->f_count))
+		__fput(file);
+}
+
+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)
+{
+	struct dentry *dentry = file->f_dentry;
+	struct vfsmount *mnt = file->f_vfsmnt;
+	struct inode *inode = dentry->d_inode;
+
+	might_sleep();
+	/*
+	 * The function eventpoll_release() should be the first called
+	 * in the file cleanup chain.
+	 */
+	eventpoll_release(file);
+	locks_remove_flock(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))
+		cdev_put(inode->i_cdev);
+	fops_put(file->f_op);
+	if (file->f_mode & FMODE_WRITE)
+		put_write_access(inode);
+	file_kill(file);
+	file->f_dentry = NULL;
+	file->f_vfsmnt = NULL;
+	file_free(file);
+	dput(dentry);
+	mntput(mnt);
+}
+
+struct file fastcall *fget(unsigned int fd)
+{
+	struct file *file;
+	struct files_struct *files = current->files;
+
+	spin_lock(&files->file_lock);
+	file = fcheck_files(files, fd);
+	if (file)
+		get_file(file);
+	spin_unlock(&files->file_lock);
+	return file;
+}
+
+EXPORT_SYMBOL(fget);
+
+/*
+ * Lightweight file lookup - no refcnt increment if fd table isn't shared. 
+ * You can use this only if it is guranteed that the current task already 
+ * holds a refcnt to that file. That check has to be done at fget() only
+ * 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 *file;
+	struct files_struct *files = current->files;
+
+	*fput_needed = 0;
+	if (likely((atomic_read(&files->count) == 1))) {
+		file = fcheck_files(files, fd);
+	} else {
+		spin_lock(&files->file_lock);
+		file = fcheck_files(files, fd);
+		if (file) {
+			get_file(file);
+			*fput_needed = 1;
+		}
+		spin_unlock(&files->file_lock);
+	}
+	return file;
+}
+
+
+void put_filp(struct file *file)
+{
+	if (atomic_dec_and_test(&file->f_count)) {
+		security_file_free(file);
+		file_kill(file);
+		file_free(file);
+	}
+}
+
+void file_move(struct file *file, struct list_head *list)
+{
+	if (!list)
+		return;
+	file_list_lock();
+	list_move(&file->f_list, list);
+	file_list_unlock();
+}
+
+void file_kill(struct file *file)
+{
+	if (!list_empty(&file->f_list)) {
+		file_list_lock();
+		list_del_init(&file->f_list);
+		file_list_unlock();
+	}
+}
+
+int fs_may_remount_ro(struct super_block *sb)
+{
+	struct list_head *p;
+
+	/* 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_list);
+		struct inode *inode = file->f_dentry->d_inode;
+
+		/* File with pending delete? */
+		if (inode->i_nlink == 0)
+			goto too_bad;
+
+		/* Writeable file? */
+		if (S_ISREG(inode->i_mode) && (file->f_mode & FMODE_WRITE))
+			goto too_bad;
+	}
+	file_list_unlock();
+	return 1; /* Tis' cool bro. */
+too_bad:
+	file_list_unlock();
+	return 0;
+}
+
+void __init files_init(unsigned long mempages)
+{ 
+	int n; 
+	/* One file with associated inode and dcache is very roughly 1K. 
+	 * Per default don't use more than 10% of our memory for files. 
+	 */ 
+
+	n = (mempages * (PAGE_SIZE / 1024)) / 10;
+	files_stat.max_files = n; 
+	if (files_stat.max_files < NR_FILE)
+		files_stat.max_files = NR_FILE;
+}