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