fs/ncpfs/file.c

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