303 lines
7.4 KiB
C
303 lines
7.4 KiB
C
/*
|
|
* 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>
|
|
|
|
#include "coda_int.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;
|
|
mutex_lock(&coda_inode->i_mutex);
|
|
|
|
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;
|
|
mutex_unlock(&coda_inode->i_mutex);
|
|
|
|
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, fl_owner_t id)
|
|
{
|
|
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;
|
|
mutex_lock(&host_inode->i_mutex);
|
|
err = host_file->f_op->fsync(host_file, host_dentry, datasync);
|
|
mutex_unlock(&host_inode->i_mutex);
|
|
}
|
|
|
|
if ( !err && !datasync ) {
|
|
lock_kernel();
|
|
err = venus_fsync(coda_inode->i_sb, coda_i2f(coda_inode));
|
|
unlock_kernel();
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
const 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,
|
|
};
|
|
|