linux/fs/ncpfs/file.c
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   1/*
   2 *  file.c
   3 *
   4 *  Copyright (C) 1995, 1996 by Volker Lendecke
   5 *  Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
   6 *
   7 */
   8
   9#include <asm/uaccess.h>
  10#include <asm/system.h>
  11
  12#include <linux/time.h>
  13#include <linux/kernel.h>
  14#include <linux/errno.h>
  15#include <linux/fcntl.h>
  16#include <linux/stat.h>
  17#include <linux/mm.h>
  18#include <linux/slab.h>
  19#include <linux/vmalloc.h>
  20#include <linux/sched.h>
  21
  22#include <linux/ncp_fs.h>
  23#include "ncplib_kernel.h"
  24
  25static int ncp_fsync(struct file *file, struct dentry *dentry, int datasync)
  26{
  27        return 0;
  28}
  29
  30/*
  31 * Open a file with the specified read/write mode.
  32 */
  33int ncp_make_open(struct inode *inode, int right)
  34{
  35        int error;
  36        int access;
  37
  38        error = -EINVAL;
  39        if (!inode) {
  40                printk(KERN_ERR "ncp_make_open: got NULL inode\n");
  41                goto out;
  42        }
  43
  44        DPRINTK("ncp_make_open: opened=%d, volume # %u, dir entry # %u\n",
  45                atomic_read(&NCP_FINFO(inode)->opened), 
  46                NCP_FINFO(inode)->volNumber, 
  47                NCP_FINFO(inode)->dirEntNum);
  48        error = -EACCES;
  49        mutex_lock(&NCP_FINFO(inode)->open_mutex);
  50        if (!atomic_read(&NCP_FINFO(inode)->opened)) {
  51                struct ncp_entry_info finfo;
  52                int result;
  53
  54                /* tries max. rights */
  55                finfo.access = O_RDWR;
  56                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  57                                        inode, NULL, OC_MODE_OPEN,
  58                                        0, AR_READ | AR_WRITE, &finfo);
  59                if (!result)
  60                        goto update;
  61                /* RDWR did not succeeded, try readonly or writeonly as requested */
  62                switch (right) {
  63                        case O_RDONLY:
  64                                finfo.access = O_RDONLY;
  65                                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  66                                        inode, NULL, OC_MODE_OPEN,
  67                                        0, AR_READ, &finfo);
  68                                break;
  69                        case O_WRONLY:
  70                                finfo.access = O_WRONLY;
  71                                result = ncp_open_create_file_or_subdir(NCP_SERVER(inode),
  72                                        inode, NULL, OC_MODE_OPEN,
  73                                        0, AR_WRITE, &finfo);
  74                                break;
  75                }
  76                if (result) {
  77                        PPRINTK("ncp_make_open: failed, result=%d\n", result);
  78                        goto out_unlock;
  79                }
  80                /*
  81                 * Update the inode information.
  82                 */
  83        update:
  84                ncp_update_inode(inode, &finfo);
  85                atomic_set(&NCP_FINFO(inode)->opened, 1);
  86        }
  87
  88        access = NCP_FINFO(inode)->access;
  89        PPRINTK("ncp_make_open: file open, access=%x\n", access);
  90        if (access == right || access == O_RDWR) {
  91                atomic_inc(&NCP_FINFO(inode)->opened);
  92                error = 0;
  93        }
  94
  95out_unlock:
  96        mutex_unlock(&NCP_FINFO(inode)->open_mutex);
  97out:
  98        return error;
  99}
 100
 101static ssize_t
 102ncp_file_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 103{
 104        struct dentry *dentry = file->f_path.dentry;
 105        struct inode *inode = dentry->d_inode;
 106        size_t already_read = 0;
 107        off_t pos;
 108        size_t bufsize;
 109        int error;
 110        void* freepage;
 111        size_t freelen;
 112
 113        DPRINTK("ncp_file_read: enter %s/%s\n",
 114                dentry->d_parent->d_name.name, dentry->d_name.name);
 115
 116        if (!ncp_conn_valid(NCP_SERVER(inode)))
 117                return -EIO;
 118
 119        pos = *ppos;
 120
 121        if ((ssize_t) count < 0) {
 122                return -EINVAL;
 123        }
 124        if (!count)
 125                return 0;
 126        if (pos > inode->i_sb->s_maxbytes)
 127                return 0;
 128        if (pos + count > inode->i_sb->s_maxbytes) {
 129                count = inode->i_sb->s_maxbytes - pos;
 130        }
 131
 132        error = ncp_make_open(inode, O_RDONLY);
 133        if (error) {
 134                DPRINTK(KERN_ERR "ncp_file_read: open failed, error=%d\n", error);
 135                return error;
 136        }
 137
 138        bufsize = NCP_SERVER(inode)->buffer_size;
 139
 140        error = -EIO;
 141        freelen = ncp_read_bounce_size(bufsize);
 142        freepage = vmalloc(freelen);
 143        if (!freepage)
 144                goto outrel;
 145        error = 0;
 146        /* First read in as much as possible for each bufsize. */
 147        while (already_read < count) {
 148                int read_this_time;
 149                size_t to_read = min_t(unsigned int,
 150                                     bufsize - (pos % bufsize),
 151                                     count - already_read);
 152
 153                error = ncp_read_bounce(NCP_SERVER(inode),
 154                                NCP_FINFO(inode)->file_handle,
 155                                pos, to_read, buf, &read_this_time, 
 156                                freepage, freelen);
 157                if (error) {
 158                        error = -EIO;   /* NW errno -> Linux errno */
 159                        break;
 160                }
 161                pos += read_this_time;
 162                buf += read_this_time;
 163                already_read += read_this_time;
 164
 165                if (read_this_time != to_read) {
 166                        break;
 167                }
 168        }
 169        vfree(freepage);
 170
 171        *ppos = pos;
 172
 173        file_accessed(file);
 174
 175        DPRINTK("ncp_file_read: exit %s/%s\n",
 176                dentry->d_parent->d_name.name, dentry->d_name.name);
 177outrel:
 178        ncp_inode_close(inode);         
 179        return already_read ? already_read : error;
 180}
 181
 182static ssize_t
 183ncp_file_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 184{
 185        struct dentry *dentry = file->f_path.dentry;
 186        struct inode *inode = dentry->d_inode;
 187        size_t already_written = 0;
 188        off_t pos;
 189        size_t bufsize;
 190        int errno;
 191        void* bouncebuffer;
 192
 193        DPRINTK("ncp_file_write: enter %s/%s\n",
 194                dentry->d_parent->d_name.name, dentry->d_name.name);
 195        if (!ncp_conn_valid(NCP_SERVER(inode)))
 196                return -EIO;
 197        if ((ssize_t) count < 0)
 198                return -EINVAL;
 199        pos = *ppos;
 200        if (file->f_flags & O_APPEND) {
 201                pos = inode->i_size;
 202        }
 203
 204        if (pos + count > MAX_NON_LFS && !(file->f_flags&O_LARGEFILE)) {
 205                if (pos >= MAX_NON_LFS) {
 206                        return -EFBIG;
 207                }
 208                if (count > MAX_NON_LFS - (u32)pos) {
 209                        count = MAX_NON_LFS - (u32)pos;
 210                }
 211        }
 212        if (pos >= inode->i_sb->s_maxbytes) {
 213                if (count || pos > inode->i_sb->s_maxbytes) {
 214                        return -EFBIG;
 215                }
 216        }
 217        if (pos + count > inode->i_sb->s_maxbytes) {
 218                count = inode->i_sb->s_maxbytes - pos;
 219        }
 220        
 221        if (!count)
 222                return 0;
 223        errno = ncp_make_open(inode, O_WRONLY);
 224        if (errno) {
 225                DPRINTK(KERN_ERR "ncp_file_write: open failed, error=%d\n", errno);
 226                return errno;
 227        }
 228        bufsize = NCP_SERVER(inode)->buffer_size;
 229
 230        already_written = 0;
 231
 232        bouncebuffer = vmalloc(bufsize);
 233        if (!bouncebuffer) {
 234                errno = -EIO;   /* -ENOMEM */
 235                goto outrel;
 236        }
 237        while (already_written < count) {
 238                int written_this_time;
 239                size_t to_write = min_t(unsigned int,
 240                                      bufsize - (pos % bufsize),
 241                                      count - already_written);
 242
 243                if (copy_from_user(bouncebuffer, buf, to_write)) {
 244                        errno = -EFAULT;
 245                        break;
 246                }
 247                if (ncp_write_kernel(NCP_SERVER(inode), 
 248                    NCP_FINFO(inode)->file_handle,
 249                    pos, to_write, bouncebuffer, &written_this_time) != 0) {
 250                        errno = -EIO;
 251                        break;
 252                }
 253                pos += written_this_time;
 254                buf += written_this_time;
 255                already_written += written_this_time;
 256
 257                if (written_this_time != to_write) {
 258                        break;
 259                }
 260        }
 261        vfree(bouncebuffer);
 262
 263        file_update_time(file);
 264
 265        *ppos = pos;
 266
 267        if (pos > inode->i_size) {
 268                inode->i_size = pos;
 269        }
 270        DPRINTK("ncp_file_write: exit %s/%s\n",
 271                dentry->d_parent->d_name.name, dentry->d_name.name);
 272outrel:
 273        ncp_inode_close(inode);         
 274        return already_written ? already_written : errno;
 275}
 276
 277static int ncp_release(struct inode *inode, struct file *file) {
 278        if (ncp_make_closed(inode)) {
 279                DPRINTK("ncp_release: failed to close\n");
 280        }
 281        return 0;
 282}
 283
 284const struct file_operations ncp_file_operations =
 285{
 286        .llseek         = remote_llseek,
 287        .read           = ncp_file_read,
 288        .write          = ncp_file_write,
 289        .ioctl          = ncp_ioctl,
 290#ifdef CONFIG_COMPAT
 291        .compat_ioctl   = ncp_compat_ioctl,
 292#endif
 293        .mmap           = ncp_mmap,
 294        .release        = ncp_release,
 295        .fsync          = ncp_fsync,
 296};
 297
 298const struct inode_operations ncp_file_inode_operations =
 299{
 300        .setattr        = ncp_notify_change,
 301};
 302