1 files changed, 300 insertions, 0 deletions

diff --git a/fs/coda/file.c b/fs/coda/file.c
new file mode 100644
index 000000000000..e6bc022568f3
--- /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,
+};
+