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root/fs/ncpfs/file.c

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DEFINITIONS

This source file includes following definitions.
  1. ncp_fsync
  2. ncp_make_open
  3. ncp_file_read
  4. ncp_file_write
  5. ncp_release
  6. ncp_remote_llseek

/*
 *  file.c
 *
 *  Copyright (C) 1995, 1996 by Volker Lendecke
 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
 *
 */

#include <asm/uaccess.h>
#include <asm/system.h>

#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>

#include <linux/ncp_fs.h>
#include "ncplib_kernel.h"

static int ncp_fsync(struct file *file, struct dentry *dentry, int datasync)
{
        return 0;
}

/*
 * Open a file with the specified read/write mode.
 */
int ncp_make_open(struct inode *inode, int right)
{
        int error;
        int access;

        error = -EINVAL;
        if (!inode) {
                printk(KERN_ERR "ncp_make_open: got NULL inode\n");
                goto out;
        }

        DPRINTK("ncp_make_open: opened=%d, volume # %u, dir entry # %u\n",
                atomic_read(&NCP_FINFO(inode)->opened), 
                NCP_FINFO(inode)->volNumber, 
                NCP_FINFO(inode)->dirEntNum);
        error = -EACCES;
        mutex_lock(&NCP_FINFO(inode)->open_mutex);
        if (!atomic_read(&NCP_FINFO(inode)->opened)) {
                struct ncp_entry_info finfo;
                int result;

                /* tries max. rights */
                finfo.access = O_RDWR;
                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
                                        inode, NULL, OC_MODE_OPEN,
                                        0, AR_READ | AR_WRITE, &finfo);
                if (!result)
                        goto update;
                /* RDWR did not succeeded, try readonly or writeonly as requested */
                switch (right) {
                        case O_RDONLY:
                                finfo.access = O_RDONLY;
                                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
                                        inode, NULL, OC_MODE_OPEN,
                                        0, AR_READ, &finfo);
                                break;
                        case O_WRONLY:
                                finfo.access = O_WRONLY;
                                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
                                        inode, NULL, OC_MODE_OPEN,
                                        0, AR_WRITE, &finfo);
                                break;
                }
                if (result) {
                        PPRINTK("ncp_make_open: failed, result=%d\n", result);
                        goto out_unlock;
                }
                /*
                 * Update the inode information.
                 */
        update:
                ncp_update_inode(inode, &finfo);
                atomic_set(&NCP_FINFO(inode)->opened, 1);
        }

        access = NCP_FINFO(inode)->access;
        PPRINTK("ncp_make_open: file open, access=%x\n", access);
        if (access == right || access == O_RDWR) {
                atomic_inc(&NCP_FINFO(inode)->opened);
                error = 0;
        }

out_unlock:
        mutex_unlock(&NCP_FINFO(inode)->open_mutex);
out:
        return error;
}

static ssize_t
ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
{
        struct dentry *dentry = file->f_path.dentry;
        struct inode *inode = dentry->d_inode;
        size_t already_read = 0;
        off_t pos;
        size_t bufsize;
        int error;
        void* freepage;
        size_t freelen;

        DPRINTK("ncp_file_read: enter %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);

        if (!ncp_conn_valid(NCP_SERVER(inode)))
                return -EIO;

        pos = *ppos;

        if ((ssize_t) count < 0) {
                return -EINVAL;
        }
        if (!count)
                return 0;
        if (pos > inode->i_sb->s_maxbytes)
                return 0;
        if (pos + count > inode->i_sb->s_maxbytes) {
                count = inode->i_sb->s_maxbytes - pos;
        }

        error = ncp_make_open(inode, O_RDONLY);
        if (error) {
                DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
                return error;
        }

        bufsize = NCP_SERVER(inode)->buffer_size;

        error = -EIO;
        freelen = ncp_read_bounce_size(bufsize);
        freepage = vmalloc(freelen);
        if (!freepage)
                goto outrel;
        error = 0;
        /* First read in as much as possible for each bufsize. */
        while (already_read < count) {
                int read_this_time;
                size_t to_read = min_t(unsigned int,
                                     bufsize - (pos % bufsize),
                                     count - already_read);

                error = ncp_read_bounce(NCP_SERVER(inode),
                                NCP_FINFO(inode)->file_handle,
                                pos, to_read, buf, &read_this_time, 
                                freepage, freelen);
                if (error) {
                        error = -EIO;   /* NW errno -> Linux errno */
                        break;
                }
                pos += read_this_time;
                buf += read_this_time;
                already_read += read_this_time;

                if (read_this_time != to_read) {
                        break;
                }
        }
        vfree(freepage);

        *ppos = pos;

        file_accessed(file);

        DPRINTK("ncp_file_read: exit %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);
outrel:
        ncp_inode_close(inode);         
        return already_read ? already_read : error;
}

static ssize_t
ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
        struct dentry *dentry = file->f_path.dentry;
        struct inode *inode = dentry->d_inode;
        size_t already_written = 0;
        off_t pos;
        size_t bufsize;
        int errno;
        void* bouncebuffer;

        DPRINTK("ncp_file_write: enter %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);
        if (!ncp_conn_valid(NCP_SERVER(inode)))
                return -EIO;
        if ((ssize_t) count < 0)
                return -EINVAL;
        pos = *ppos;
        if (file->f_flags & O_APPEND) {
                pos = inode->i_size;
        }

        if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
                if (pos >= MAX_NON_LFS) {
                        return -EFBIG;
                }
                if (count > MAX_NON_LFS - (u32)pos) {
                        count = MAX_NON_LFS - (u32)pos;
                }
        }
        if (pos >= inode->i_sb->s_maxbytes) {
                if (count || pos > inode->i_sb->s_maxbytes) {
                        return -EFBIG;
                }
        }
        if (pos + count > inode->i_sb->s_maxbytes) {
                count = inode->i_sb->s_maxbytes - pos;
        }
        
        if (!count)
                return 0;
        errno = ncp_make_open(inode, O_WRONLY);
        if (errno) {
                DPRINTK(KERN_ERR "ncp_file_write: open failed, error=%d\n", errno);
                return errno;
        }
        bufsize = NCP_SERVER(inode)->buffer_size;

        already_written = 0;

        bouncebuffer = vmalloc(bufsize);
        if (!bouncebuffer) {
                errno = -EIO;   /* -ENOMEM */
                goto outrel;
        }
        while (already_written < count) {
                int written_this_time;
                size_t to_write = min_t(unsigned int,
                                      bufsize - (pos % bufsize),
                                      count - already_written);

                if (copy_from_user(bouncebuffer, buf, to_write)) {
                        errno = -EFAULT;
                        break;
                }
                if (ncp_write_kernel(NCP_SERVER(inode), 
                    NCP_FINFO(inode)->file_handle,
                    pos, to_write, bouncebuffer, &written_this_time) != 0) {
                        errno = -EIO;
                        break;
                }
                pos += written_this_time;
                buf += written_this_time;
                already_written += written_this_time;

                if (written_this_time != to_write) {
                        break;
                }
        }
        vfree(bouncebuffer);

        file_update_time(file);

        *ppos = pos;

        if (pos > inode->i_size) {
                inode->i_size = pos;
        }
        DPRINTK("ncp_file_write: exit %s/%s\n",
                dentry->d_parent->d_name.name, dentry->d_name.name);
outrel:
        ncp_inode_close(inode);         
        return already_written ? already_written : errno;
}

static int ncp_release(struct inode *inode, struct file *file) {
        if (ncp_make_closed(inode)) {
                DPRINTK("ncp_release: failed to close\n");
        }
        return 0;
}

static loff_t ncp_remote_llseek(struct file *file, loff_t offset, int origin)
{
        loff_t ret;
        lock_kernel();
        ret = generic_file_llseek_unlocked(file, offset, origin);
        unlock_kernel();
        return ret;
}

const struct file_operations ncp_file_operations =
{
        .llseek         = ncp_remote_llseek,
        .read           = ncp_file_read,
        .write          = ncp_file_write,
        .ioctl          = ncp_ioctl,
#ifdef CONFIG_COMPAT
        .compat_ioctl   = ncp_compat_ioctl,
#endif
        .mmap           = ncp_mmap,
        .release        = ncp_release,
        .fsync          = ncp_fsync,
};

const struct inode_operations ncp_file_inode_operations =
{
        .setattr        = ncp_notify_change,
};

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