/* * linux/fs/9p/vfs_file.c * * This file contians vfs file ops for 9P2000. * * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to: * Free Software Foundation * 51 Franklin Street, Fifth Floor * Boston, MA 02111-1301 USA * */ #include <linux/module.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/file.h> #include <linux/stat.h> #include <linux/string.h> #include <linux/smp_lock.h> #include <linux/inet.h> #include <linux/version.h> #include <linux/list.h> #include <asm/uaccess.h> #include <linux/idr.h> #include "debug.h" #include "v9fs.h" #include "9p.h" #include "v9fs_vfs.h" #include "fid.h" /** * v9fs_file_open - open a file (or directory) * @inode: inode to be opened * @file: file being opened * */ int v9fs_file_open(struct inode *inode, struct file *file) { struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); struct v9fs_fid *v9fid, *fid; struct v9fs_fcall *fcall = NULL; int open_mode = 0; unsigned int iounit = 0; int newfid = -1; long result = -1; dprintk(DEBUG_VFS, "inode: %p file: %p \n", inode, file); v9fid = v9fs_fid_get_created(file->f_dentry); if (!v9fid) v9fid = v9fs_fid_lookup(file->f_dentry); if (!v9fid) { dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n"); return -EBADF; } if (!v9fid->fidcreate) { fid = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL); if (fid == NULL) { dprintk(DEBUG_ERROR, "Out of Memory\n"); return -ENOMEM; } fid->fidopen = 0; fid->fidcreate = 0; fid->fidclunked = 0; fid->iounit = 0; fid->v9ses = v9ses; newfid = v9fs_get_idpool(&v9ses->fidpool); if (newfid < 0) { eprintk(KERN_WARNING, "newfid fails!\n"); return -ENOSPC; } result = v9fs_t_walk(v9ses, v9fid->fid, newfid, NULL, NULL); if (result < 0) { v9fs_put_idpool(newfid, &v9ses->fidpool); dprintk(DEBUG_ERROR, "rewalk didn't work\n"); return -EBADF; } fid->fid = newfid; v9fid = fid; /* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */ /* translate open mode appropriately */ open_mode = file->f_flags & 0x3; if (file->f_flags & O_EXCL) open_mode |= V9FS_OEXCL; if (v9ses->extended) { if (file->f_flags & O_TRUNC) open_mode |= V9FS_OTRUNC; if (file->f_flags & O_APPEND) open_mode |= V9FS_OAPPEND; } result = v9fs_t_open(v9ses, newfid, open_mode, &fcall); if (result < 0) { dprintk(DEBUG_ERROR, "open failed, open_mode 0x%x: %s\n", open_mode, FCALL_ERROR(fcall)); kfree(fcall); return result; } iounit = fcall->params.ropen.iounit; kfree(fcall); } else { /* create case */ newfid = v9fid->fid; iounit = v9fid->iounit; v9fid->fidcreate = 0; } file->private_data = v9fid; v9fid->rdir_pos = 0; v9fid->rdir_fcall = NULL; v9fid->fidopen = 1; v9fid->filp = file; v9fid->iounit = iounit; return 0; } /** * v9fs_file_lock - lock a file (or directory) * @inode: inode to be opened * @file: file being opened * * XXX - this looks like a local only lock, we should extend into 9P * by using open exclusive */ static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl) { int res = 0; struct inode *inode = filp->f_dentry->d_inode; dprintk(DEBUG_VFS, "filp: %p lock: %p\n", filp, fl); /* No mandatory locks */ if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID) return -ENOLCK; if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) { filemap_fdatawrite(inode->i_mapping); filemap_fdatawait(inode->i_mapping); invalidate_inode_pages(&inode->i_data); } return res; } /** * v9fs_file_read - read from a file * @filep: file pointer to read * @data: data buffer to read data into * @count: size of buffer * @offset: offset at which to read data * */ static ssize_t v9fs_file_read(struct file *filp, char __user * data, size_t count, loff_t * offset) { struct inode *inode = filp->f_dentry->d_inode; struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); struct v9fs_fid *v9f = filp->private_data; struct v9fs_fcall *fcall = NULL; int fid = v9f->fid; int rsize = 0; int result = 0; int total = 0; int n; dprintk(DEBUG_VFS, "\n"); rsize = v9ses->maxdata - V9FS_IOHDRSZ; if (v9f->iounit != 0 && rsize > v9f->iounit) rsize = v9f->iounit; do { if (count < rsize) rsize = count; result = v9fs_t_read(v9ses, fid, *offset, rsize, &fcall); if (result < 0) { printk(KERN_ERR "9P2000: v9fs_t_read returned %d\n", result); kfree(fcall); return total; } else *offset += result; n = copy_to_user(data, fcall->params.rread.data, result); if (n) { dprintk(DEBUG_ERROR, "Problem copying to user %d\n", n); kfree(fcall); return -EFAULT; } count -= result; data += result; total += result; kfree(fcall); if (result < rsize) break; } while (count); return total; } /** * v9fs_file_write - write to a file * @filep: file pointer to write * @data: data buffer to write data from * @count: size of buffer * @offset: offset at which to write data * */ static ssize_t v9fs_file_write(struct file *filp, const char __user * data, size_t count, loff_t * offset) { struct inode *inode = filp->f_dentry->d_inode; struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); struct v9fs_fid *v9fid = filp->private_data; struct v9fs_fcall *fcall; int fid = v9fid->fid; int result = -EIO; int rsize = 0; int total = 0; char *buf; dprintk(DEBUG_VFS, "data %p count %d offset %x\n", data, (int)count, (int)*offset); rsize = v9ses->maxdata - V9FS_IOHDRSZ; if (v9fid->iounit != 0 && rsize > v9fid->iounit) rsize = v9fid->iounit; buf = kmalloc(v9ses->maxdata - V9FS_IOHDRSZ, GFP_KERNEL); if (!buf) return -ENOMEM; do { if (count < rsize) rsize = count; result = copy_from_user(buf, data, rsize); if (result) { dprintk(DEBUG_ERROR, "Problem copying from user\n"); kfree(buf); return -EFAULT; } dump_data(buf, rsize); result = v9fs_t_write(v9ses, fid, *offset, rsize, buf, &fcall); if (result < 0) { eprintk(KERN_ERR, "error while writing: %s(%d)\n", FCALL_ERROR(fcall), result); kfree(fcall); kfree(buf); return result; } else *offset += result; kfree(fcall); fcall = NULL; if (result != rsize) { eprintk(KERN_ERR, "short write: v9fs_t_write returned %d\n", result); break; } count -= result; data += result; total += result; } while (count); kfree(buf); return total; } struct file_operations v9fs_file_operations = { .llseek = generic_file_llseek, .read = v9fs_file_read, .write = v9fs_file_write, .open = v9fs_file_open, .release = v9fs_dir_release, .lock = v9fs_file_lock, };