1 files changed, 300 insertions, 0 deletions
diff --git a/fs/coda/file.c b/fs/coda/file.c
new file mode 100644
index 00000000000..e6bc022568f
--- /dev/null
+++ b/fs/coda/file.c
@@ -0,0 +1,300 @@
+/*
+ * File operations for Coda.
+ * Original version: (C) 1996 Peter Braam 
+ * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
+ *
+ * Carnegie Mellon encourages users of this code to contribute improvements
+ * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
+ */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/stat.h>
+#include <linux/errno.h>
+#include <linux/smp_lock.h>
+#include <linux/string.h>
+#include <asm/uaccess.h>
+
+#include <linux/coda.h>
+#include <linux/coda_linux.h>
+#include <linux/coda_fs_i.h>
+#include <linux/coda_psdev.h>
+#include <linux/coda_proc.h>
+
+/* if CODA_STORE fails with EOPNOTSUPP, venus clearly doesn't support
+ * CODA_STORE/CODA_RELEASE and we fall back on using the CODA_CLOSE upcall */
+static int use_coda_close;
+
+static ssize_t
+coda_file_read(struct file *coda_file, char __user *buf, size_t count, loff_t *ppos)
+{
+	struct coda_file_info *cfi;
+	struct file *host_file;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	if (!host_file->f_op || !host_file->f_op->read)
+		return -EINVAL;
+
+	return host_file->f_op->read(host_file, buf, count, ppos);
+}
+
+static ssize_t
+coda_file_sendfile(struct file *coda_file, loff_t *ppos, size_t count,
+		   read_actor_t actor, void *target)
+{
+	struct coda_file_info *cfi;
+	struct file *host_file;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	if (!host_file->f_op || !host_file->f_op->sendfile)
+		return -EINVAL;
+
+	return host_file->f_op->sendfile(host_file, ppos, count, actor, target);
+}
+
+static ssize_t
+coda_file_write(struct file *coda_file, const char __user *buf, size_t count, loff_t *ppos)
+{
+	struct inode *host_inode, *coda_inode = coda_file->f_dentry->d_inode;
+	struct coda_file_info *cfi;
+	struct file *host_file;
+	ssize_t ret;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	if (!host_file->f_op || !host_file->f_op->write)
+		return -EINVAL;
+
+	host_inode = host_file->f_dentry->d_inode;
+	down(&coda_inode->i_sem);
+
+	ret = host_file->f_op->write(host_file, buf, count, ppos);
+
+	coda_inode->i_size = host_inode->i_size;
+	coda_inode->i_blocks = (coda_inode->i_size + 511) >> 9;
+	coda_inode->i_mtime = coda_inode->i_ctime = CURRENT_TIME_SEC;
+	up(&coda_inode->i_sem);
+
+	return ret;
+}
+
+static int
+coda_file_mmap(struct file *coda_file, struct vm_area_struct *vma)
+{
+	struct coda_file_info *cfi;
+	struct coda_inode_info *cii;
+	struct file *host_file;
+	struct inode *coda_inode, *host_inode;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	if (!host_file->f_op || !host_file->f_op->mmap)
+		return -ENODEV;
+
+	coda_inode = coda_file->f_dentry->d_inode;
+	host_inode = host_file->f_dentry->d_inode;
+	coda_file->f_mapping = host_file->f_mapping;
+	if (coda_inode->i_mapping == &coda_inode->i_data)
+		coda_inode->i_mapping = host_inode->i_mapping;
+
+	/* only allow additional mmaps as long as userspace isn't changing
+	 * the container file on us! */
+	else if (coda_inode->i_mapping != host_inode->i_mapping)
+		return -EBUSY;
+
+	/* keep track of how often the coda_inode/host_file has been mmapped */
+	cii = ITOC(coda_inode);
+	cii->c_mapcount++;
+	cfi->cfi_mapcount++;
+
+	return host_file->f_op->mmap(host_file, vma);
+}
+
+int coda_open(struct inode *coda_inode, struct file *coda_file)
+{
+	struct file *host_file = NULL;
+	int error;
+	unsigned short flags = coda_file->f_flags & (~O_EXCL);
+	unsigned short coda_flags = coda_flags_to_cflags(flags);
+	struct coda_file_info *cfi;
+
+	coda_vfs_stat.open++;
+
+	cfi = kmalloc(sizeof(struct coda_file_info), GFP_KERNEL);
+	if (!cfi) {
+		unlock_kernel();
+		return -ENOMEM;
+	}
+
+	lock_kernel();
+
+	error = venus_open(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags,
+			   &host_file); 
+	if (error || !host_file) {
+		kfree(cfi);
+		unlock_kernel();
+		return error;
+	}
+
+	host_file->f_flags |= coda_file->f_flags & (O_APPEND | O_SYNC);
+
+	cfi->cfi_magic = CODA_MAGIC;
+	cfi->cfi_mapcount = 0;
+	cfi->cfi_container = host_file;
+
+	BUG_ON(coda_file->private_data != NULL);
+	coda_file->private_data = cfi;
+
+	unlock_kernel();
+	return 0;
+}
+
+int coda_flush(struct file *coda_file)
+{
+	unsigned short flags = coda_file->f_flags & ~O_EXCL;
+	unsigned short coda_flags = coda_flags_to_cflags(flags);
+	struct coda_file_info *cfi;
+	struct inode *coda_inode;
+	int err = 0, fcnt;
+
+	lock_kernel();
+
+	coda_vfs_stat.flush++;
+
+	/* last close semantics */
+	fcnt = file_count(coda_file);
+	if (fcnt > 1)
+		goto out;
+
+	/* No need to make an upcall when we have not made any modifications
+	 * to the file */
+	if ((coda_file->f_flags & O_ACCMODE) == O_RDONLY)
+		goto out;
+
+	if (use_coda_close)
+		goto out;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+
+	coda_inode = coda_file->f_dentry->d_inode;
+
+	err = venus_store(coda_inode->i_sb, coda_i2f(coda_inode), coda_flags,
+			  coda_file->f_uid);
+
+	if (err == -EOPNOTSUPP) {
+		use_coda_close = 1;
+		err = 0;
+	}
+
+out:
+	unlock_kernel();
+	return err;
+}
+
+int coda_release(struct inode *coda_inode, struct file *coda_file)
+{
+	unsigned short flags = (coda_file->f_flags) & (~O_EXCL);
+	unsigned short coda_flags = coda_flags_to_cflags(flags);
+	struct coda_file_info *cfi;
+	struct coda_inode_info *cii;
+	struct inode *host_inode;
+	int err = 0;
+
+	lock_kernel();
+	coda_vfs_stat.release++;
+ 
+	if (!use_coda_close) {
+		err = venus_release(coda_inode->i_sb, coda_i2f(coda_inode),
+				    coda_flags);
+		if (err == -EOPNOTSUPP) {
+			use_coda_close = 1;
+			err = 0;
+		}
+	}
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+
+	if (use_coda_close)
+		err = venus_close(coda_inode->i_sb, coda_i2f(coda_inode),
+				  coda_flags, coda_file->f_uid);
+
+	host_inode = cfi->cfi_container->f_dentry->d_inode;
+	cii = ITOC(coda_inode);
+
+	/* did we mmap this file? */
+	if (coda_inode->i_mapping == &host_inode->i_data) {
+		cii->c_mapcount -= cfi->cfi_mapcount;
+		if (!cii->c_mapcount)
+			coda_inode->i_mapping = &coda_inode->i_data;
+	}
+
+	fput(cfi->cfi_container);
+	kfree(coda_file->private_data);
+	coda_file->private_data = NULL;
+
+	unlock_kernel();
+	return err;
+}
+
+int coda_fsync(struct file *coda_file, struct dentry *coda_dentry, int datasync)
+{
+	struct file *host_file;
+	struct dentry *host_dentry;
+	struct inode *host_inode, *coda_inode = coda_dentry->d_inode;
+	struct coda_file_info *cfi;
+	int err = 0;
+
+	if (!(S_ISREG(coda_inode->i_mode) || S_ISDIR(coda_inode->i_mode) ||
+	      S_ISLNK(coda_inode->i_mode)))
+		return -EINVAL;
+
+	cfi = CODA_FTOC(coda_file);
+	BUG_ON(!cfi || cfi->cfi_magic != CODA_MAGIC);
+	host_file = cfi->cfi_container;
+
+	coda_vfs_stat.fsync++;
+
+	if (host_file->f_op && host_file->f_op->fsync) {
+		host_dentry = host_file->f_dentry;
+		host_inode = host_dentry->d_inode;
+		down(&host_inode->i_sem);
+		err = host_file->f_op->fsync(host_file, host_dentry, datasync);
+		up(&host_inode->i_sem);
+	}
+
+	if ( !err && !datasync ) {
+		lock_kernel();
+		err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode));
+		unlock_kernel();
+	}
+
+	return err;
+}
+
+struct file_operations coda_file_operations = {
+	.llseek		= generic_file_llseek,
+	.read		= coda_file_read,
+	.write		= coda_file_write,
+	.mmap		= coda_file_mmap,
+	.open		= coda_open,
+	.flush		= coda_flush,
+	.release	= coda_release,
+	.fsync		= coda_fsync,
+	.sendfile	= coda_file_sendfile,
+};
+