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-rw-r--r--fs/coda/file.c300
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,
+};
+